Nonvolatile Digital Computing with Ferroelectric FET
20200027508 ยท 2020-01-23
Inventors
- Xueqing Li (State College, PA)
- Sumitha George (State College, PA)
- John Sampson (State College, PA)
- Sumeet Gupta (State College, PA)
- Suman Datta (South Bend, IN)
- Vijaykrishnan Narayanan (State College, PA)
- Kaisheng Ma (State College, PA)
Cpc classification
G11C14/009
PHYSICS
G11C13/0007
PHYSICS
H01L29/78391
ELECTRICITY
International classification
G11C14/00
PHYSICS
G11C11/16
PHYSICS
G11C13/00
PHYSICS
Abstract
Embodiments include nonvolatile a memory (NVM) device that can be configured for logic switching and/or digital computing. For example, embodiments of the NVM device can be configured as any one or combination of a memory cell, a D flip flop (DFF), a Backup and Restore circuit (B&R circuit), and/or a latch for a DFF. Any of the NVM devices can have a Fe field effect transistors (FeFET) configured to exploit the I.sub.DSV.sub.G hysteresis of the steep switch at low voltage for logic memory synergy. The FeFET-based devices can be configured to include a wide hysteresis, a steep hysteresis edge, and high ratio between the two I.sub.DS states at V.sub.G=0.
Claims
1. A nonvolatile memory (NVM) device, comprising a circuit topology having at least one Fe field effect transistor (FeFET) configured to exhibit a wide current-voltage (I-V) hysteresis covering zero gate bias.
2. The NVM device recited in claim 1, wherein: the circuit topology is configured as a backup and restore circuit (B&R circuit); the B&R circuit comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a fifth transistor, M.sub.5, M.sub.5 having an M.sub.5-source, an M.sub.5-gate, and an M.sub.5-drain; a sixth transistor, M.sub.6, M.sub.6 having an M.sub.6-source, an M.sub.6-gate, and an M.sub.6-drain; a seventh transistor, M.sub.7, M.sub.7 having an M.sub.7-source, an M.sub.7-gate, and an M.sub.7-drain; an eighth transistor, M.sub.8, M.sub.8 having an M.sub.8-source, an M.sub.8-gate, and an M.sub.8-drain; a first branch and a second branch, the first branch including M.sub.1, M.sub.2, M.sub.5, M.sub.7, and a ground, GND, the second branch including M.sub.3, M.sub.4, M.sub.6, and M.sub.8; each of M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 is a metal-oxide-semiconductor field-effect transistor (MOSFET) and each of M.sub.5 and M.sub.6 is a FeFET; M.sub.1-gate being connected to a backup control signal input, B.sub.kp_input and M.sub.3-gate; M.sub.1-drain being connected to M.sub.2-drain; M.sub.1-drain being configured to be connected to a slave latch via the first branch; M.sub.1-source being connected to M.sub.5-source and M.sub.7-drain; M.sub.2-drain being connected to M.sub.1-drain; M.sub.2-drain being configured to be connected to the slave latch via the first branch; M.sub.2-gate being connected to a backup and restore control signal input, B.sub.kp+R.sub.str and M.sub.3-gate; M.sub.2-source being connected to M.sub.6-gate, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source; M.sub.3-drain being connected to M.sub.4-drain; M.sub.3-drain being configured to be connected to the slave latch via the second branch; M.sub.3-gate being connected to B.sub.kp+R.sub.str and M.sub.1-gate; M.sub.3-source being connected to M.sub.5-gate, M.sub.6-drain, M.sub.5-drain, M.sub.2-source, and M.sub.6-gate; M.sub.4-drain being connected to M.sub.3-drain; M.sub.4-drain being configured to be connected to the slave latch via the second branch; M.sub.4-gate being connected to a backup control signal output, B.sub.kp_output; M.sub.4-source being connected to M.sub.6-source and M.sub.8-drain; M.sub.5-drain being connected to M.sub.2-source, M.sub.5-gate, M.sub.6-gate, M.sub.6-drain, and M.sub.3-source; M.sub.5-gate being connected to M.sub.3-source, M.sub.6-drain, M.sub.6-gate, M.sub.2-source, and M.sub.5-drain; M.sub.5-source being connected to M.sub.7-drain and M.sub.1-source; M.sub.6-drain being connected to M.sub.3-source, M.sub.5-gate, M.sub.6-gate, M.sub.5-drain, and M.sub.2-source; M.sub.6-gate being connected to M.sub.2-source, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source; M.sub.6-source being connected to M.sub.4-source and M.sub.8-drain; M.sub.7-drain being connected to M.sub.1-source and M.sub.5-source; M.sub.7-gate being connected to a restore input control signal, R.sub.str; M.sub.7-source being connected to GND via the first branch; M.sub.8-drain being connected to M.sub.4-source and M.sub.6-source; M.sub.8-gate being connected to M.sub.7-gate; and M.sub.8-source being connected to GND via the second branch.
3. The NVM device recited in claim 1, wherein: the circuit topology is configured as a D-Flip Flop (DFF); the DFF comprising a master latch, a slave latch, and a backup and restore circuit (B&R circuit); the master latch comprising: a first master inverter M.sub.INV1, a second master inverter, M.sub.INV2, a third master inverter, M.sub.INV3, and a master transmission gate, M.sub.GATE; input of M.sub.INV1 being connected to a data input signal, D; output of M.sub.INV1 being connected to input of M.sub.INV2; input of M.sub.INV2 being connected to output of M.sub.INV1; output of M.sub.INV2 being connected to input of M.sub.INV3; input of M.sub.INV3 being connected to output of M.sub.INV2; output of M.sub.INV3 being connected to input of M.sub.GATE; input of M.sub.GATE being connected to output of M.sub.INV3; and output of M.sub.GATE being connected to input of M.sub.INV2 and output of M.sub.INV1; the slave latch comprising: a first slave inverter, S.sub.INV1, a second slave inverter, S.sub.INV2, a third slave inverter, S.sub.INV3, and a slave transmission gate, S.sub.GATE; input of S.sub.INV1 being connected to output of M.sub.INV2; input of S.sub.INV2 being connected to output of S.sub.INV1; output of S.sub.INV2 being connected to input of S.sub.INV3 and to a data output Q; input of S.sub.INV3 being connected to output of S.sub.INV2; output of S.sub.INV3 being connected to input of S.sub.GATE; and output of S.sub.GATE being connected to input of S.sub.INV2 and output of S.sub.INV1; and the B&R circuit comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a fifth transistor, M.sub.5, M.sub.5 having an M.sub.5-source, an M.sub.5-gate, and an M.sub.5-drain; a sixth transistor, M.sub.6, M.sub.6 having an M.sub.6-source, an M.sub.6-gate, and an M.sub.6-drain; a seventh transistor, M.sub.7, M.sub.7 having an M.sub.7-source, an M.sub.7-gate, and an M.sub.7-drain; an eighth transistor, M.sub.8, M.sub.8 having an M.sub.8-source, an M.sub.8-gate, and an M.sub.8-drain; a first branch and a second branch, the first branch including M.sub.1, M.sub.2, M.sub.5, M.sub.7, and a ground, GND, the second branch including M.sub.3, M.sub.4, M.sub.6, and M.sub.8; each of M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 is a metal-oxide-semiconductor field-effect transistor (MOSFET) and each of M.sub.5 and M.sub.6 is a FeFET; M.sub.1-gate is connected to a backup control signal input, B.sub.kp_input and M.sub.3-gate; M.sub.1-drain is connected to M.sub.2-drain; M.sub.1-drain is configured to be connected to the slave latch via the first branch; M.sub.1-source is connected to M.sub.5-source and M.sub.7-drain; M.sub.2-drain is connected to M.sub.1-drain; M.sub.2-drain is configured to be connected to the slave latch via the first branch; M.sub.2-gate is connected to a backup and restore control signal input, B.sub.kp+R.sub.str and M.sub.3-gate; M.sub.2-source is connected to M.sub.6-gate, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source; M.sub.3-drain is connected to M.sub.4-drain; M.sub.3-drain is configured to be connected to the slave latch via the second branch; M.sub.3-gate is connected to B.sub.kp+R.sub.str and M.sub.1-gate; M.sub.3-source is connected to M.sub.5-gate, M.sub.6-drain, M.sub.5-drain, M.sub.2-source, and M.sub.6-gate; M.sub.4-drain is connected to M.sub.3-drain; M.sub.4-drain is configured to be connected to the slave latch via the second branch; M.sub.4-gate is connected to a backup control signal output, B.sub.kp_output; M.sub.4-source is connected to M.sub.6-source and M.sub.8-drain; M.sub.5-drain is connected to M.sub.2-source, M.sub.5-gate, M.sub.6-gate, M.sub.6-drain, and M.sub.3-source; M.sub.5-gate is connected to M.sub.3-source, M.sub.6-drain, M.sub.6-gate, M.sub.2-source, and M.sub.5-drain; M.sub.5-source is connected to M.sub.7-drain and M.sub.1-source; M.sub.6-drain is connected to M.sub.3-source, M.sub.5-gate, M.sub.6-gate, M.sub.5-drain, and M.sub.2-source; M.sub.6-gate is connected to M.sub.2-source, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source; M.sub.6-source is connected to M.sub.4-source and M.sub.8-drain; M.sub.7-drain is connected to M.sub.1-source and M.sub.5-source; M.sub.7-gate is connected to a restore input control signal, R.sub.str; M.sub.7-source is connected to GND via the first branch; M.sub.8-drain is connected to M.sub.4-source and M.sub.6-source; M.sub.8-gate is connected to M.sub.7-gate; and M.sub.8-source is connected to GND via the second branch.
4. (canceled)
5. The NVM device recited in claim 1, wherein: the circuit topology is configured as a latch configured to have an input D; the latch comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a fifth transistor, M.sub.5, M.sub.5 having an M.sub.5-source, an M.sub.5-gate, and an M.sub.5-drain; a sixth transistor, M.sub.6, M.sub.6 having an M.sub.6-source, an M.sub.6-gate, and an M.sub.6-drain; a seventh transistor, M.sub.7, M.sub.7 having an M.sub.7-source, an M.sub.7-gate, and an M.sub.7-drain; an eighth transistor, M.sub.8, M.sub.8 having an M.sub.8-source, an M.sub.8-gate, and an M.sub.8-drain; a ninth transistor, M.sub.9, M.sub.9 having an M.sub.9-source, an M.sub.9-gate, and an M.sub.9-drain; a tenth transistor, M.sub.10, M.sub.10 having an M.sub.10-source, an M.sub.10-gate, and an M.sub.10-drain; an eleventh transistor, M.sub.11, M.sub.11 having an M.sub.11-source, an M.sub.11-gate, and an M.sub.11-drain; a twelfth transistor, M.sub.12, M.sub.12 having an M.sub.12-source, an M.sub.12-gate, and an M.sub.12-drain; a thirteenth transistor, M.sub.5b, M.sub.5b having an M.sub.5b-source, an M.sub.5b-gate, and an M.sub.5b-drain; a fourteenth transistor, M.sub.6b, M.sub.6b having an M.sub.6b-source, an M.sub.6b-gate, and an M.sub.6b-drain; each of M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, M.sub.8, M.sub.9, M.sub.10, and M.sub.11 is a metal oxide semiconductor field effect transistor (MOSFET); each of M.sub.5 and M.sub.6 is a FeFET; M.sub.1-drain being connected to M.sub.2-drain and a data input D; M.sub.1-gate being connected to a clock driver, CLK; M.sub.1-source being connected to M.sub.2-source, M.sub.3-gate, M.sub.5-gate, M.sub.7-gate, M-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain; M.sub.2-drain being connected to M.sub.1-drain and data input D; M.sub.2-gate being connected to CLK; M.sub.2-source being connected to M.sub.1-source, M.sub.3-gate, M.sub.5-gate, M.sub.7-gate, M-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain; M.sub.3-drain being connected to a voltage supply, V.sub.DD; M.sub.3-gate being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain; M.sub.3-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-gate, M.sub.9-source, M.sub.10 source, M.sub.5-drain, and M.sub.5b-drain; M.sub.4-drain being connected to V.sub.DD; M.sub.4-gate being connected to a data output QN, a data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain; M.sub.4-source being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-gate, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain; M.sub.5-drain being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain; M.sub.5-gate being connected to M.sub.1-source, M.sub.2-source, M.sub.5-drain, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5b-gate, and M.sub.5b-drain; M.sub.5-source being connected to M.sub.7-drain; M.sub.5b-drain being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5-drain; M.sub.5b-gate being connected to M.sub.5-gate; M.sub.5b-source being connected to ground, GND; M.sub.6-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.4-gate; M.sub.6-gate being connected to data output QN, data output Q, M.sub.6-drain, M.sub.6b-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.4-gate; M.sub.6-source being connected to M.sub.8-drain; M.sub.6b-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.4-gate, and M.sub.6-drain; M.sub.6b-gate being connected to M.sub.6-gate; M.sub.6b-source being connected to GND; M.sub.7-drain being connected to M.sub.5-source; M.sub.7-gate being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.5-drain, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain; M.sub.7-source being connected to GND; M.sub.8-drain being connected to M.sub.6-source; M.sub.8-gate being connected to data output QN, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.8-source can be connected to GND; M.sub.9-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.4-gate, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain; M.sub.9-gate being connected to V.sub.DD; M.sub.9-source being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.5-drain, M.sub.10-source, and M.sub.5b-drain; M.sub.10-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.4-gate, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain; M.sub.10-gate being connected to GND; M.sub.10-source being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.5-drain, and M.sub.5b-drain; M.sub.11-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.4-gate, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain; M.sub.11-gate being connected to CLK; M.sub.11-source being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain; M.sub.12-drain being connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.4-gate, M.sub.6b-drain, and M.sub.6-drain; M.sub.12-gate being connected to CLK; and M.sub.12-source being connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.5-drain, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain.
6. The NVM device recited in claim 1, wherein: the circuit topology is configured as a latch configured to have a differential-driving input pair D/DN; the latch comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a fifth transistor, M.sub.5, M.sub.5 having an M.sub.5-source, an M.sub.5-gate, and an M.sub.5-drain; a sixth transistor, M.sub.6, M.sub.6 having an M.sub.6-source, an M.sub.6-gate, and an M.sub.6-drain; a seventh transistor, M.sub.7. M.sub.7 having an M.sub.7-source, an M.sub.7-gate, and an M.sub.7-drain; an eighth transistor, M.sub.8, M.sub.8 having an M.sub.8-source, an M.sub.8-gate, and an M.sub.8-drain; each of M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 is a metal oxide semiconductor field effect transistor (MOSFET); each of M.sub.5 and M.sub.6 is a FeFET; M.sub.1-drain being connected to a data input D; M.sub.1-gate being connected to a clock driver, CLK; M.sub.1-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, a data output Q, a data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.2-drain being connected to data input DN; M.sub.2-gate being connected to M.sub.1-gate; M.sub.2-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.1-source, M.sub.7-gate, M.sub.7-drain, a data output Q, a data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.3-drain being connected to a voltage supply, V.sub.DD; M.sub.3-gate being connected to M.sub.5-gate, M.sub.1-source, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.3-source being connected to M.sub.5-drain; M.sub.4-drain being connected to V.sub.DD; M.sub.4-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.1-source; M.sub.4-source being connected to M.sub.6-drain; M.sub.5-drain being connected to M.sub.3-source; M5-gate being connected to M.sub.1-source, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.5-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.1-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.6-drain being connected to M.sub.4-source; M.sub.6-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.1-source, and M.sub.4-gate; M.sub.6-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.1-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.7-drain being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.1-source, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.7-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.1-source, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.7-source being connected to ground, GND; M.sub.8-drain being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.1-source, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate; M.sub.8-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.1-source, M.sub.6-gate, and M.sub.4-gate; and M.sub.8-source being connected to GND.
7. The NVM device recited in claim 1, wherein: the circuit topology is configured as a latch configured to have a differential-driving input pair D/DN; the latch comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a fifth transistor, M.sub.5, M.sub.5 having an M.sub.5-source, an M.sub.5-gate, and an M.sub.5-drain; a sixth transistor, M.sub.6, M.sub.6 having an M.sub.6-source, an M.sub.6-gate, and an M.sub.6-drain; a seventh transistor, M.sub.7. M.sub.7 having an M.sub.7-source, an M.sub.7-gate, and an M.sub.7-drain; an eighth transistor, M.sub.8, M.sub.8 having an M.sub.8-source, an M.sub.8-gate, and an M.sub.8-drain; a ninth transistor, M.sub.9, M.sub.9 having an M.sub.9-source, an M.sub.9-gate, and an M.sub.9-drain; a tenth transistor, M.sub.10, M.sub.10 having an M.sub.10-source, an M.sub.10-gate, and an M.sub.10-drain; each of M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.9, and M.sub.10 is a metal oxide semiconductor field effect transistor (MOSFET); each of M.sub.5, M.sub.6, M.sub.7, and M.sub.8 is a FeFET; M.sub.1-drain being connected to a data input D; M.sub.1-gate being connected to a clock driver, CLK; M.sub.1-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, a data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, a data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.2-drain being connected to a data input DN; M.sub.2-gate being connected to M.sub.1-gate; M.sub.2-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.1-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.3-drain being connected to a voltage supply, V.sub.DD; M.sub.3-gate being connected to M.sub.5-gate, M.sub.1-source, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.3-source being connected to M.sub.5-drain; M.sub.4-drain being connected to V.sub.DD; M.sub.4-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.1-source, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.4-source being connected to M.sub.6-drain; M.sub.5-drain being connected to M.sub.3-source; M.sub.5-gate c being connected to M.sub.1-source, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.5-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.1-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.6-drain being connected to M.sub.4-source; M.sub.6-gate being connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.1-source, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.6-source being connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.1-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.7-drain can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.1-source, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.7-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.1-source, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate; M.sub.7-source can be connected to M.sub.9-drain; M.sub.10-drain can be connected to M.sub.8-source; M.sub.10-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.1-source; and M.sub.10-source can be connected to ground, GND.
8-18. (canceled)
19. The NVM device recited in claim 1, wherein: the circuit topology is configured as a 2-transistor (2T) memory cell; the 2T-memory cell comprising: a first transistor T.sub.1, a second transistor T.sub.2, a bit line, BL, a first Wordline, WLW, and a second Wordline, WLR; T.sub.1 being a metal oxide semiconductor field effect transistor (MOSFET) and T.sub.2 being a FeFET; T.sub.1 having a T.sub.1-source, a T.sub.1-gate, and a T.sub.1-drain; T.sub.2 having a T.sub.2-source, a T.sub.2-gate, and a T.sub.2-drain; WLW being configured to receive and/or transmit a write signal for write operations; WLR being configured to receive and/or transmit a read signal for read operations; T.sub.2-drain being connected to BL and WLW; T.sub.2-gate being connected to WLW; T.sub.2-source being connected to T.sub.1-drain; T.sub.1-gate being connected to WLR and BL; and T.sub.1-source being connected to ground, GND.
20. The NVM device recited in claim 19, further comprising a plurality of 2T-memory cells arrange in a memory cell array.
21. The NVM device recited in claim 20, wherein the memory cell array comprises: a first 2T-memory cell, a second 2T-memory cell, a third 2T-memory cell, a third 2T-memory cell, a fourth 2T-memory cell, a fifth 2T-memory cell, a sixth 2T-memory cell, a seventh 2T-memory cell, and an eighth 2T-memory cell, each memory cell having a T.sub.1 and a T.sub.2, wherein T.sub.1 is a MOSFET and T.sub.2 is a FeEFT, wherein: the first 2T-memory cell has a first T.sub.1 and a first T.sub.2; the second 2T-memory cell has a second T.sub.1 and a second T.sub.2; the third 2T-memory cell has a third T.sub.1 and a third T.sub.2; the fourth 2T-memory cell has a fourth T.sub.1 and a fourth T.sub.2; the fifth 2T-memory cell has a fifth T.sub.1 and a fifth T.sub.2; the sixth 2T-memory cell 124 has a sixth T.sub.1 and a sixth T.sub.2; the seventh 2T-memory cell has a seventh T.sub.1 and a seventh T.sub.2; the eighth 2T-memory cell 124 has an eighth T.sub.1 and a eighth T.sub.2; and a first BL, BL1, a second BL, BL2, a third BL, BL3, and a fourth BL, BL4; a first WLW, WLW1, a second WLW, WLW2, a first WLR, WLR1, and a second WLR, WLR2, wherein each of WLW1 and WLW2 is configured to receive and/or transmit a write signal for write operations, and each of WLR1 and WLR2 is configured to receive and/or transmit a read signal for read operations; the first cell T.sub.2-drain being connected to BL1 and WLW1; the first cell T.sub.2-gate being connected to WLW1; the first cell T.sub.2-source being connected to first cell T.sub.1-drain; the first cell T.sub.1-gate being connected to WLR1 and BL1; the first cell T.sub.1-source being connected to ground, GND; the second cell T.sub.2-drain being connected to BL2 and WLW1; the second cell T.sub.2-gate being connected to WLW1; the second cell T.sub.2-source being connected to second cell T.sub.1-drain; the second cell T.sub.1-gate being connected to WLR1 and BL2; the second cell T.sub.1-source being connected to GND; the third cell T.sub.2-drain being connected to BL3 and WLW1; the third cell T.sub.2-gate being connected to WLW1; the third cell T.sub.2-source being connected to third cell T.sub.1-drain; the third cell T.sub.1-gate being connected to WLR1 and BL3; the third cell T.sub.1-source being connected to GND; the fourth cell T.sub.2-drain being connected to BL4 and WLW1; the fourth cell T.sub.2-gate being connected to WLW1; the fourth cell T.sub.2-source being connected to fourth cell T.sub.1-drain; the fourth cell T.sub.1-gate being connected to WLR1 and BL4; the fourth cell T.sub.1-source being connected to GND; the fifth cell T.sub.2-drain being connected to BL1 and WLW2; the fifth cell T.sub.2-gate being connected to WLW2; the fifth cell T.sub.2-source being connected to fifth cell T.sub.1-drain; the fifth cell T.sub.1-gate being connected to WLR2 and BL1; the fifth cell T.sub.1-source being connected to GND; the sixth cell T.sub.2-drain being connected to BL2 and WLW2; the sixth cell T.sub.2-gate being connected to WLW2; the sixth cell T.sub.2-source being connected to sixth cell T.sub.1-drain; the sixth cell T.sub.1-gate being connected to WLR2 and BL2; the sixth cell T.sub.1-source being connected to GND; the seventh cell T.sub.2-drain being connected to BL3 and WLW2; the seventh cell T.sub.2-gate being connected to WLW2; the seventh cell T.sub.2-source being connected to seventh cell T.sub.1-drain; the seventh cell T.sub.1-gate being connected to WLR2 and BL3; the seventh cell T.sub.1-source being connected to GND; the eighth cell T.sub.2-drain being connected to BL4 and WLW2; the eighth cell T.sub.2-gate being connected to WLW2; the eighth cell T.sub.2-source being connected to eighth cell T.sub.1-drain; the eighth cell T.sub.1-gate being connected to WLR2 and BL4; and the eighth cell T.sub.1-source being connected to GND.
22. The NVM device recited in claim 1, wherein: the circuit topology is configured as a 3-transistor (3T) memory cell; the 3T-memory cell comprising: a first transistor, T.sub.1, a second transistor, T.sub.2, a third transistor T.sub.3, a first bit line, BLW, a second bit line, BLR, a Wordline Write, WLW, a Wordline Read, WLR, and a Wordline-Readline, WLRL; each of T.sub.1 and T.sub.3 is a metal oxide semiconductor field effect transistor (MOSFET), and T.sub.2 is a FeFET; T.sub.1 has a T.sub.1-source, a T.sub.1-gate, and a T.sub.1-drain; T.sub.2 has a T.sub.2-source, a T.sub.2-gate, and a T.sub.2-drain; T.sub.3 has a T.sub.3-source, a T.sub.3-gate, and a T.sub.3-drain; T.sub.1-drain being connected to T.sub.2-gate; T.sub.1-gate being connected to WLW; T.sub.1-source being connected to BLW; T.sub.2-drain being connected to T.sub.3-source; T.sub.2-gate being connected to T.sub.1-drain; T.sub.2-source being connected to WLRW; T.sub.3-drain being connected to BLR; T.sub.3-gate being connected to WLR; T.sub.3-source being connected to T.sub.2-drain; at least one of BLW, WLW, and WLRW being connected to ground, GND; and WLR being connected to a voltage supply, V.sub.DD.
23. The NVM device recited in claim 1, wherein: the circuit topology is configured as a 3-transistor (3T) memory cell; the 3T-memory cell comprising: a first transistor, T.sub.1, a second transistor, T.sub.2, a third transistor T.sub.3, a bit line, BL, a Wordline Write, WLW, a Wordline Read, WLR, and a Wordline-Readline, WLRL; each of T.sub.1 and T.sub.3 is a metal oxide semiconductor field effect transistor (MOSFET), and T.sub.2 is a FeFET; T.sub.1 has a T.sub.1-source, a T.sub.1-gate, and a T.sub.1-drain; T.sub.2 has a T.sub.2-source, a T.sub.2-gate, and a T.sub.2-drain; T.sub.3 has a T.sub.3-source, a T.sub.3-gate, and a T.sub.3-drain; T.sub.1-drain being connected to T.sub.2-gate; T.sub.1-gate being connected to WLW; T.sub.1-source being connected to BL; T.sub.2-drain being connected to T.sub.3-drain; T.sub.2-gate being connected to T.sub.1-drain; T.sub.2-source being connected to WLRW; T.sub.3-drain being connected to T.sub.2-drain; T.sub.3-gate being connected to WLR; and T.sub.3-source being connected to BL.
24. The NVM device recited in claim 1, wherein: the circuit topology is configured as a backup and restore circuit (B&R circuit); the B&R circuit comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a first branch comprising M.sub.1, M.sub.3, and ground, GND; a second branch comprising M.sub.2, M.sub.4, and GND; each of M.sub.1 and M.sub.2 is a metal oxide semiconductor field effect transistor (MOSFET); each of M.sub.3 and M.sub.4 is a FeFET; M.sub.1-drain being connected to M.sub.3-source; M.sub.1-gate being connected to a restore signal input signal and M.sub.2-gate; M.sub.1-source being connected to GND; M.sub.2-drain being connected to M.sub.4-source; M.sub.2-gate being connected to M.sub.1-gate; M.sub.3-drain configured to be connected to a slave latch via the first branch; M.sub.3-drain being connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-gate, and to the second branch; M.sub.3-gate being connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-drain, and to the second branch; M.sub.3-source being connected to M.sub.1-drain; M.sub.4-drain configured to be connected to the slave latch via the second branch; M.sub.4-drain being connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-gate, and to the first branch; M.sub.4-gate being connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-drain, and to the first branch; and M.sub.4-source being connected to M.sub.2-drain.
25. The NVM device recited in claim 1, wherein: the circuit topology is configured as a D-Flip Flop (DFF); the DFF comprising a master latch, a slave latch, and a backup and restore circuit (B&R circuit); the master latch comprising: a first master inverter M.sub.INV1, a second master inverter, M.sub.INV2, a third master inverter, M.sub.INV3, and a master transmission gate, M.sub.GATE; input of M.sub.INV1 being connected to a data input signal, D; output of M.sub.INV1 being connected to input of M.sub.INV2; input of M.sub.INV2 being connected to output of M.sub.INV1; output of M.sub.INV2 being connected to input of M.sub.INV3; input of M.sub.INV3 being connected to output of M.sub.INV2; output of M.sub.INV3 being connected to input of M.sub.GATE; input of M.sub.GATE being connected to output of M.sub.INV3; and output of M.sub.GATE being connected to input of M.sub.INV2 and output of M.sub.INV1; the slave latch comprising: a first slave inverter, S.sub.INV1, a second slave inverter, S.sub.INV2, a third slave inverter, S.sub.INV3, and a slave transmission gate, S.sub.GATE; input of S.sub.INV1 being connected to output of M.sub.INV2; input of S.sub.INV2 being connected to output of S.sub.INV1; output of S.sub.INV2 being connected to input of S.sub.INV3 and to a data output Q; input of S.sub.INV3 being connected to output of S.sub.INV2; output of S.sub.INV3 being connected to input of S.sub.GATE; and output of S.sub.GATE being connected to input of S.sub.INV2 and output of S.sub.INV1; and the B&R circuit comprising: a first transistor, M.sub.1, M.sub.1 having an M.sub.1-source, an M.sub.1-gate, and an M.sub.1-drain; a second transistor, M.sub.2, M.sub.2 having an M.sub.2-source, an M.sub.2-gate, and an M.sub.2-drain; a third transistor, M.sub.3, M.sub.3 having an M.sub.3-source, an M.sub.3-gate, and an M.sub.3-drain; a fourth transistor, M.sub.4, M.sub.4 having an M.sub.4-source, an M.sub.4-gate, and an M.sub.4-drain; a first branch comprising M.sub.1, M.sub.3, and ground, GND; a second branch comprising M.sub.2, M.sub.4, and GND; each of M.sub.1 and M.sub.2 is a metal oxide semiconductor field effect transistor (MOSFET); each of M.sub.3 and M.sub.4 is a FeFET; M.sub.1-drain being connected to M.sub.3-source; M.sub.1-gate being connected to a restore signal input signal and M.sub.2-gate; M.sub.1-source being connected to GND; M.sub.2-drain being connected to M.sub.4-source; M.sub.2-gate being connected to M.sub.1-gate; M.sub.3-drain configured to be connected to a slave latch via the first branch; M.sub.3-drain being connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-gate, and to the second branch; M.sub.3-gate being connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-drain, and to the second branch; M.sub.3-source being connected to M.sub.1-drain; M.sub.4-drain configured to be connected to the slave latch via the second branch; M.sub.4-drain being connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-gate, and to the first branch; M.sub.4-gate being connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-drain, and to the first branch; and M.sub.4-source being connected to M.sub.2-drain.
26. The NVM device recited in claim 24, wherein: M.sub.3-drain being connected to output of S.sub.GATE, output of S.sub.INV1, and input of S.sub.INV2; M.sub.4-drain being connected to input of S.sub.INV3, output of S.sub.INV2, and data output Q.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The above and other objects, aspects, features, advantages and possible applications of the present innovation will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings. Like reference numbers used in the drawings may identify like components.
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DETAILED DESCRIPTION OF THE INVENTION
[0120] The following description is of exemplary embodiments that are presently contemplated for carrying out the present invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles and features of the present invention. The scope of the present invention is not limited by this description.
[0121] Embodiments include nonvolatile a memory (NVM) device 100 that can be configured for logic switching and/or digital computing. For example, embodiments of the NVM device 100 can be configured as any one or combination of a memory cell 124, a D flip flop (DFF) 120, a Backup and Restore circuit (B&R circuit) 116, and/or a latch 118, 122 for a DFF 120.
[0122] Referring to
[0123] Topologies for embodiments of the NVM devices 100 disclosed herein can include at least one FeFET 102 configured to have a wide current-voltage (I-V) hysteresis covering zero gate bias. For example, circuit topologies of embodiments of the NVM devices 100 can be configured to exploit the wide hysteresis feature that can be obtained from the use of an embodiment of the FeFET 102. Embodiments of the FeFET 102 can be configured to behave concurrently as a nonvolatile memory and a logic device with inherent compatibility with Boolean signaling. These and other features can reduce the complexity and energy consumption of the interface with logic gates. Additionally, embodiments of the FeFET 102 can provide a memory operation without static current during a write operation. In some embodiments, the FeFET 102, when used embodiments of the NVM devices 100 can be configured to exhibit a steep hysteresis edge and a high ratio between the two drain-source current states (I.sub.DS states) at a gate voltage (V.sub.G)=0. These two states can be the two locally stable states shown in
[0124] Capacitance matching may be beneficial to obtain the characteristics in
[0125] Embodiments of the NVM device 100 can be configured as a B&R circuit 116 and/or a DFF 120 having an embodiment of the DFF 120 as part of its accessory circuitry. Such a NVM device 100 can be configured to maintain its state during a power outage and/or during an intermittent power supply. This can be useful for nonvolatile computing (e.g., prevent computation progress loss due to either an unexpected or scheduled power outage). For example, embodiments of the B&R circuit 116 and/or a DFF 120 can be used for backing up memory and DFF states to on-chip nonvolatile memory elements. Nonvolatile computing techniques can also be useful for energy harvesting, and in particular energy harvesting with Internet-of-Things (IoT) applications where frequent check-pointing is generally required under the notoriously intermittent supply provided by energy harvesting mechanisms. Nonvolatile computing techniques, via in situ backup methods, can also provide more energy savings in power-gating applications (e.g., cut off leakage power for higher energy efficiency).
[0126]
[0127] The B&R circuit 116 can further include a first branch 101 and a second branch 103. The first branch 101 can include M.sub.1, M.sub.2, M.sub.5, M.sub.7, and GND. The second branch 103 can include M.sub.3, M.sub.4, M.sub.6, and M.sub.8. Depending on the inputs, either the first branch 101 or the second branch 103 operates as a backup branch or a restore branch. For example, when the first branch 101 operates as a backup branch, the second branch 103 operates as a restore branch. When the first branch 101 operates as a restore branch, the second branch 103 operates as a backup branch. Particular note should be made to the cross-coupled circuit connection between M.sub.5 and the second branch 103 and M.sub.6 and the first branch 101. This can facilitate backup and restore operations in only one step without static current consumptions.
[0128] In some embodiments, the B&R circuit 116 can be connected to a slave latch 118. (See
[0129] In at least one embodiment, M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 are MOSFETs. In at least one embodiment, M.sub.5 and M.sub.6 are FeFETs 102. M.sub.1-gate can be connected to a backup control signal input, B.sub.kp_input and M.sub.3-gate. M.sub.1-drain can be connected to M.sub.2-drain. M.sub.1-drain can be configured to be connected to a slave latch 118, which can be via the first branch 101. M.sub.1-source can be connected to M.sub.5-source and M.sub.7-drain. M.sub.2-drain can be connected to M.sub.1-drain. M.sub.2-drain can be configured to be connected to the slave latch 118, which can be via the first branch 101. M.sub.2-gate can be connected to a backup and restore control signal input, B.sub.kp+R.sub.str and M.sub.3-gate. M.sub.2-source can be connected to M.sub.6-gate, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source. M.sub.3-drain can be connected to M.sub.4-drain. M.sub.3-drain can be configured to be connected to the slave latch 118, which can be via the second branch 103. M.sub.3-gate can be connected to B.sub.kp+R.sub.str and M.sub.1-gate. M.sub.3-source can be connected to M.sub.5-gate, M.sub.6-drain, M.sub.5-drain, M.sub.2-source, and M.sub.6-gate. M.sub.4-drain can be connected to M.sub.3-drain. M.sub.4-drain can be configured to be connected to the slave latch 118, which can be via the second branch 103. M.sub.4-gate can be connected to a backup control signal output, B.sub.kp_output. M.sub.4-source can be connected to M.sub.6-source and M.sub.8-drain. M.sub.5-drain can be connected to M.sub.2-source, M.sub.5-gate, M.sub.6-gate, M.sub.6-drain, and M.sub.3-source. M.sub.5-gate can be connected to M.sub.3-source, M.sub.6-drain, M.sub.6-gate, M.sub.2-source, and M.sub.5-drain. M.sub.5-source can be connected to M.sub.7-drain and M.sub.1-source. M.sub.6-drain can be connected to M.sub.3-source, M.sub.5-gate, M.sub.6-gate, M.sub.5-drain, and M.sub.2-source. M.sub.6-gate can be connected to M.sub.2-source, M.sub.5-drain, M.sub.5-gate, M.sub.6-drain, and M.sub.3-source. M.sub.6-source can be connected to M.sub.4-source and M.sub.8-drain. M.sub.7-drain can be connected to M.sub.1-source and M.sub.5-source. M.sub.7-gate can be connected to a restore input control signal, R.sub.str. M.sub.7-source can be connected to ground, GND, which can be via the first branch 101. M.sub.8-drain can be connected to M.sub.4-source and M.sub.6-source. M.sub.8-gate can be connected to M.sub.7-gate. M.sub.8-source can be connected to GND, which can be via the second branch 103.
[0130] Referring to
[0131] The master latch 122 can have a first master inverter M.sub.INV1, a second master inverter, M.sub.INV2, a third master inverter, M.sub.INV3, and a master transmission gate, M.sub.GATE. The input of M.sub.INV1 can be connected to a data input signal, D. The output of M.sub.INV1 can be connected to the input of M.sub.INV2. The input of M.sub.INV2 can be connected to the output of M.sub.INV1. The output of M.sub.INV2 can be connected to the input of M.sub.INV3. The input of M.sub.INV3 can be connected to the output of M.sub.INV2. The output of M.sub.INV3 can be connected to the input of M.sub.GATE. The input of M.sub.GATE can be connected to the output of M.sub.INV3. The output of M.sub.GATE can be connected to the input of M.sub.INV2 and the output of M.sub.INV1.
[0132] The slave latch 118 can have a first slave inverter, S.sub.INV1, a second slave inverter, S.sub.INV2, a third slave inverter, S.sub.INV3, and a slave transmission gate, S.sub.GATE. The input of S.sub.INV1 can be connected to the output of M.sub.INV2. The input of S.sub.INV2 can be connected to the output of S.sub.INV1. The output of S.sub.INV2 can be connected to the input of S.sub.INV3 and to a data output Q. The input of S.sub.INV3 can be connected to the output of S.sub.INV2. The output of S.sub.INV3 can be connected to the input of S.sub.GATE. The output of S.sub.GATE can be connected to the input of S.sub.INV2 and the output of S.sub.INV1.
[0133] A clock driver, CLK can be used to generate an in-phase clock signal, c, and opposite-phase clock signal, cn, for M.sub.INV1, M.sub.GATE, S.sub.INV1, and/or S.sub.GATE. Embodiments of the CLK can include a first clock inverter, CLK.sub.INV1, having an output connected to an input of a second clock inverter, CLK.sub.INV2. CLK.sub.INV1 can be configured to generate cn. CLK.sub.INV2 can be configured to generate c. Each of M.sub.GATE and S.sub.GATE can be a gate circuit for transmitting or blocking the output signal from the master latch 122 or slave latch 118, respectively, in response to the clock signal from CLK. For example, the DFF 120 can be configured such that each of M.sub.GATE and S.sub.GATE passes the output signal of the master latch 122 or slave latch 118, respectively, when the clock signal is HIGH (e.g., M.sub.GATE or S.sub.GATE becomes conductive). Each of M.sub.GATE and S.sub.GATE can be configured to block the output signal of the master latch 116 or slave latch 118, respectively, when the clock signal is LOW (e.g., M.sub.GATE or S.sub.GATE becomes non-conductive).
[0134] Each of M.sub.1-drain and M.sub.2-drain can be connected to the output of S.sub.GATE, the output of S.sub.INV1, and the input of S.sub.INV2. For example, the first branch 101 can be connected to the output of S.sub.GATE, the output of S.sub.INV1, and the input of S.sub.INV2. Each of M.sub.3-drain and M.sub.4-drain can be connected to the input of S.sub.INV3, the output of S.sub.INV2, and data output Q. For example, the second branch 103 can be connected to the input of S.sub.INV3, the output of S.sub.INV2, and data output Q.
[0135] In some embodiments, when both B.sub.k and R.sub.str are low, the interface transistors (M.sub.1, M.sub.2, M.sub.3, and M.sub.4) between the slave latch 118 and the B&R circuit 116 are turned OFF by the gate signal B.sub.k and R.sub.str. This can cause the master latch 122 and slave latch 118 portions of the DFF 120 to function the same as a conventional positive-edge triggered DFF.
[0136]
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[0139] It should be noted that embodiments of the DFF 120 and/or B&R circuit 116 can be built with P-type transistors connecting to V.sub.DD with effective control signals at a low voltage.
[0140] Any one or combination of the parameters of any one or combination of FeFETs 102 can be tuned by adjusting the thickness, T.sub.FE, of the ferroelectric layer 114 and/or the area, A.sub.FE, of the ferroelectric layer 114. Adjusting T.sub.FE and/or A.sub.FE cab facilitate generating an NVM device 100 with improved energy-delay overhead during normal operations, improved backup and restore energy and delay, improved retention time, and improved yield and reliability. Improving the backup and restore energy can be beneficial for NVM devices 100 used in energy-harvesting systems experiencing intermittent power supplies. Conventional nonvolatile memory devices are limited in improvements to overall energy efficiency, as more energy spent for backup and restore operations generally results in less energy for computation. For example, for check-pointing applications, the backup and restore energy indicates a certain period of power-off time (break-even time (BET)), below which no energy savings could be achieved. Improved backup and restore time can also be beneficial for some applications when a fast response is preferred (e.g., fine-time-granularity power-gating scenarios and fast-response processors).
[0141]
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[0143] A design performance evaluation using SPICE simulations was conducted using an embodiment of the DFF 120. T.sub.FE was set to 6 nm and A.sub.FE was set to 378 nm.sup.2 (equal to 3fin_widthchannel_length) for one fin, for the optimized tradeoff. These parameter values, unless otherwise stated, were be used in the performance evaluation. A physics-based ferroelectric capacitance model in was employed to build FeFETs 102 with 10 nm PTM CMOS FinFET as the integrated MOSFET for the simulation. In the model, the ferroelectric material was calibrated by experimental results of lead zirconium titanate (PZT) films on hafnium oxide (HfO.sub.2) buffer. To reflect different polarization switching speed, in the FeFET model, the kinetic coefficient was varied from 0.04 to 0.25. The baseline CMOS volatile DFF (a conventional DFF, which is annotated as CMOS DFF in
[0144] It is contemplated that for DFFs 120 used in practical applications, energy-delay performance would be critical because the DFF 120 would still operate with a steady supply for a large portion of time. Therefore, it is meaningful that the additional acquired non-volatility does not cause high energy-delay overheads.
[0145] With semiconductor manufacturing, a process corner is a design-of-experiments technique that refers to a variation of fabrication parameters. Process corners represent the extremes of these parameter variations within which a circuit that has been etched onto the wafer must function correctly. A circuit running on devices fabricated at these process corners may run slower or faster than specified and at lower or higher temperatures and voltages, but defining bounds of these variations provides a means to measure whether the circuit is able to function satisfactorily. In order to verify the robustness of a circuit design, corner lots can be fabricated (e.g., groups of wafers with process parameters adjusted according to extremes), and used for testing. Shmoo plots can be used to identify the boundary limit beyond which a device begins to fail. Corner-lot analysis can be an effective means of testing in digital electronics. The naming convention of the process corners includes identifying three process corners: 1) typical-typical (TT) process corner, the slow-slow (SS) process corner, and a fast-fast (FF) process corner. Existing nonvolatile memory and DFF designs suffer from the non-idealities of the nonvolatile storage devices inside, especially the variations and low resistance ratio between different states of resistive memory devices. In such approaches, the worst-corner devices often greatly limit the overall system performance. For example, write pulse duration for conventional devices is much longer than average to ensure high yield, resulting in high energy consumption. Therefore, it is important to analyze how the DFF 120 performs with FeFET variations.
[0146]
[0147] The kinetic coefficient affects the polarization switching time significantly. Different practical kinetic coefficient values were adopted in the simulations to reflect different polarization switching times, as shown in Table 1.
TABLE-US-00001 TABLE 1 Performance Comparisons between DFF Designs Con- Con- Con- Embodiment ventional ventional ventional of device device device the disclosed measured simulated simulated* DFF** Tech. size 130 nm 710 nm 180 nm 10 nm Voltage 1.5 V 1.0 V 1.8 V 0.3 V-0.8 V Material PZT MJT ReRAM 6 nm HfO2, Capacitive PZT device P = 0.04, p = 0.10, p = 0.25 T.sub.Backup+Restore 2.67 S >10 S 1.3 S 277 pS, 583 pS, 1.29 pS E.sub.Backup+Restore 2.4 pJ 382 fJ 735 fJ 1.38 fJ Break-Even / 0.83 1.47 mS 55.9 nS Time S@25 C. *The results are for a conventional topology DFF of operating at 0.8 V supply (rise to 2.4 V for ReRAM write) for the shortest break-even time. **Backup and restore performance in this table is simulated at 0.5 V supply. MJT = multi-junction technology ReRAM = resistive Random Access Memory
[0148] The data in
[0149] Table 1 also summarizes the DFF 120 overall performance in comparison with the conventional designs. One of the strongest advantages of the DFF 120 over conventional designs is the orders of magnitude lower energy for backup and restore operations. Such energy savings partly come from the capability of FeFETs 102 to operate effectively at a lower voltage. Two more important factors are: (a) the fundamentally different 3-terminal FeFET device operating in a novel cross-coupled circuitry that avoids static FeFET drain-source current during backup and restore operations; (b) FeFETs of a small size that can still ensure fast and robust operations with a high ON/OFF state resistance ratio even in the presence of significant local and global variations. In contrast, existing resistive memory elements in conventional DFF designs are continuously drawing current (because of their inherent two-terminal device feature) for a long period of time to ensure yield (because of required-write-time duration variations with a much lower resistance ratio). For capacitive nonvolatile memory devices, their power inefficiency arises from a complex access interface and a large capacitance value. The low-energy backup and restore operations in the DFF 120, however, enables higher-efficiency nonvolatile computing applications. For energy harvesting systems with an intermittent supply, the saved backup and restore energy could be used for computing, leading to more forward progress and higher quality of service (QoS). For general power-gating systems, the lower backup and restore energy leads to a shorter break-even time (BET) versus the leakage energy of an idle unit, indicating significant expansion of opportunity for energy savings from fine-grained power-gating.
[0150] As noted herein, FeFETs 102, exhibiting steep-switching capability at a low voltage and the associated benefits for implementing energy-efficient Boolean logic, can be exploited to generate embodiments of the B&R circuit 116 and/or embodiments of the DFF 120. Embodiments of the DFF 120 consumes negligible static current in backup and restore operations, and remains robust even with significant global and local ferroelectric material variations across a wide 0.3 V-0.8 V supply voltage range, allowing the DFF 120 to achieve energy-efficient and low-latency backup and restore operations. Embodiments of the DFF 120 can have an ultra-low energy-delay overhead, below 2.1% in normal operations, and can operate using the same voltage supply as the Boolean logic elements with which it connects. This can facilitate energy-efficient nonvolatile computing in energy-harvesting and power-gating applications.
[0151] Embodiments of the NVM device 100 can be configured as a latch 118, 122. For example, any of the slave latches 118 and/or master latches 122 can include an embodiment of the FeFET 102 to provide an embedded logic-in-memory operation (i.e., an intrinsic nonvolatile area-efficient latch). Embodiments of the latch 118, 122 can be used to provide an improved DFF 120.
[0152] For example, conventional on-chip state backup solutions for DFF have a bottleneck of significant energy and/or latency penalties that can limit overall energy efficiency and computing progress. In addition, existing techniques generally rely on external controls that can limit compatibility and increases system complexity. Accordingly, advancements in nonvolatile computing can be achieved by use of an embodiment of an intrinsic nonvolatile area-efficient latch 118, 122 and/or DFF 120. Some embodiments of the latch 118, 122 and/or DFF 120 can be designed using embodiments of the FeFET 102. Some embodiments of the NVM device 100 using an embodiment of the latch 118, 122 and/or an embodiment of the DFF 102 can operate to consume fJ-level energy and ns-level intrinsic latency for a backup plus restore operation (e.g., 2.4 fJ in energy and 1.1 ns in time for a DFF 120 with a supply power of 0.80V).
[0153] Scheduled power-gating of very large scale integration (VLSI) computing systems has been widely adopted in both low-power portable devices and high-performance cloud server centers to cut off static leakage power. With such systems states of the registers and flip-flops in the pipelining logic should be backed up to prevent loss of computation status if the supply is removed. Similarly, mandatory state backup and restore operations can be required for battery-less portable devices powered by energy-harvesting techniques. This is because the ambient energy sources, such as vibration, photovoltaics, and radio, are essentially intermittent even with sophisticated design methods.
[0154] Embedding nonvolatile memory (NVM) into the same chip can improve nonvolatile processing (NVP) by generated a DFF 120 configured to back up the computation states of each DFF into a local on-chip NVM. Table 2 summarizes some existing DFF designs based on ferroelectric capacitor devices, MTJ devices, ReRAM devices, and compares the pros and cons against an embodiment of the DFF 120. If distributed NVM cells and interface circuitry are placed close to each DFF to build a nonvolatile DFF for local parallel backup, as illustrated in
TABLE-US-00002 TABLE 2 Performance Comparison of Conventional DFF Designs to an Embodiment of an Intrinsic Nonvolatile Area-efficient DFF Device Embodiment Conventional DFF Devices of the DFF Year 2014 2014 2014 2013 2016 2018 Feature size 130 nm 130 nm 45 nm 180 nm 10 nm 10 nm Nonvolatile PZT PZT MTJ Al/TiO.sub.2/Al NCFET with HfO.sub.2 and material Capacitor Capacitor ReRAM PZT Retention 10 hours to 10 10 years 10 years Same as PZT capacitor in Time years; varying by design theory Endurance Vaiying by matenal; >10.sup.15 10.sup.5-10.sup.10; Same as PZT capacitor in possibly >10.sub.15 10.sup.15 by 2014 theory Voltage 1.5 V 1.5 V 1.1 V 1.8 V 0.4 V-0.8 V 0.4 V-1.0 V 25% more Area overhead 64% 49% 2% 35% transistors Backup time 1.64 s 2.22 s 909 ps 10 ns @ 2.4 V 1.4 ns @ 0.5 V 1.0 ns @ 0.8 V Restore time 1.25 s 2.2 s 177 ps 1.3 s @ 0.4 V 75 ps @ 0.5 V 56 ps @ 0.8 V Backup energy 2.4 pJ 3.44 pJ 82.2 fJ 735 fJ 7.0 fJ @ 0.5 V 1.3 fJ @ 0.8 V Restore energy 2.34 pJ in total 735 fJ 9.0 fJ @ 0.5 V 1.1 fJ @ 0.8 V Additional Needed Needed Needed Needed Needed Not Needed Control
[0155] In addition, backup and restore control for distributed NV-DFFs can require additional wiring with more area and energy consumption. In addition, the processor architecture and the software needed to adapt to the control limits the compatibility of existing software and makes the operating system or processor design complicated. Furthermore, a backup triggered too early or too late will waste energy that could otherwise be saved, or result in a backup failure and rolling back in progress. These problems with conventional DFF devices are exacerbated due to the inherent nature of intermittency and unpredictability in ambient power sources.
[0156] As will be explained in detail, embodiments of the latches 118, 122 and DFFs 120 disclosed herein can be configured to have only a few extra transistors added to a conventional CMOS design, leading to a compact cell design. No additional circuitry or a different supply voltage is needed for sensing or driving functions, as would otherwise be necessary for conventional DFFs. In addition, embodiments of the latches 118, 122 and DFFs 120 can be free from external backup and restore controls because all backup and restore operations are carried out autonomously. This can improve compatibility and reduce complexity of existing logic designs with drop-in replacement of latches and DFFs, as shown in
[0157] Embodiments of the disclosed latches 118, 122 and DFFs 120 can be fast and energy-efficient, with similar delay and energy consumption to conventional volatile designs under a stable supply. Typical energy and latency for a backup plus restore operation are only at levels of fJ and ns, respectively. Note that the restore time also depends on the supply voltage recovery time. The operations could be even faster with kinetic coefficient improvement in the FeFET 102. With such a low energy and delay overhead, the utilization of harvested energy for the purpose of computing can be significantly improved. For the same reason, check-pointing and power-gating can be carried out in fine grain as needed with significantly reduced energy and delay penalties.
[0158] Many ferroelectric materials, such as PbTiO, BaTiO, Pb(ZrTi)O, HfZrO, etc., can be used to generate an embodiment of the FeFET 102.
[0159] Referring to
[0160] In at least one embodiment, M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 are MOSFETs. In at least one embodiment, M.sub.5 and M.sub.6 are FeFETs 102. M.sub.1-drain can be connected to M.sub.3-gate, M.sub.3-source, M.sub.4-source, M.sub.4-gate, data output Q, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.1-gate can be connected to a clock driver CLK. M.sub.1-source can be connected to a data input D. M.sub.2-drain can be connected to M.sub.3-gate, M.sub.3-source, M.sub.4-source, M.sub.4-gate, data output Q, M.sub.1-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.2-gate can be connected to M.sub.1-gate. M.sub.2-source can be connected to a data input DN. M.sub.3-drain can be connected to a voltage supply V.sub.DD. M.sub.3-gate can be connected to M.sub.3-source, M.sub.4-source, M.sub.4-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.3-source can be connected to M.sub.3-gate, M.sub.4-source, M.sub.4-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.4-drain can be connected to V.sub.DD. M.sub.4-gate can be connected to M.sub.3-source, M.sub.4-source, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.4-source can be connected to M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.5-drain can be connected to M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.5-gate can be connected to M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-drain, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.6-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.5-source can be connected to M.sub.7-drain. M.sub.6-drain can be connected to M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.5-drain, M.sub.6-gate, and M.sub.8-gate. M.sub.6-gate can be connected to M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, data output QN, M.sub.5-drain, M.sub.6-drain, and M.sub.8-gate. M.sub.6-source can be connected to M.sub.8-drain. M.sub.7-drain can be connected to M.sub.5-source. M.sub.7-gate can be connected to M.sub.6-gate, M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.5-drain, data output QN, M.sub.5-drain, M.sub.6-drain, and M.sub.8-gate. M.sub.7-source can be connected to GND. M.sub.8-drain can be connected to M.sub.6-source. M.sub.8-gate can be connected to M.sub.7-gate, M.sub.6-gate, M.sub.4-source, M.sub.3-source, M.sub.4-gate, M.sub.3-gate, data output Q, M.sub.1-drain, M.sub.2-drain, M.sub.5-gate, M.sub.5-drain, data output QN, M.sub.5-drain, and M.sub.6-drain. M.sub.8-source can be connected to GND.
[0161] Referring to
[0162] In at least one embodiment, M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, M.sub.8, M.sub.9, M.sub.10, and M.sub.11 are MOSFETs. In at least one embodiment, M.sub.5 and M.sub.6 are FeFETs 102. M.sub.1-drain can be connected to M.sub.2-drain and data input D. M.sub.1-gate can be connected to a clock driver CLK. M.sub.1-source can be connected to M.sub.2-source, M.sub.3-gate, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain. M.sub.2-drain can be connected to M.sub.1-drain and data input D. M.sub.2-gate can be connected to CLK. M.sub.2-source can be connected to M.sub.1-source, M.sub.3-gate, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain. M.sub.3-drain can be connected to V.sub.DD. M.sub.3-gate can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain. M3-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-gate, M.sub.9-source, M.sub.10-source, M.sub.5-drain, and M.sub.5b-drain. M.sub.4-drain can be connected to V.sub.DD. M.sub.4-gate can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.4-source can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-gate, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.5-drain can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain. M5-gate can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-drain, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, M.sub.5b-gate, and M.sub.5b-drain. M.sub.5-source can be connected to M.sub.7-drain. M.sub.5b-drain can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5-drain. M.sub.5b-gate can be connected to M.sub.5-gate. M.sub.5b-source can be connected to GND. M.sub.6-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.4-gate. M.sub.6-gate can be connected to data output QN, data output Q, M.sub.6-drain, M.sub.6b-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.4-gate. M.sub.6-source can be connected to M.sub.8-drain. M.sub.6b-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.4-gate, and M.sub.6-drain. M.sub.6b-gate can be connected to M.sub.6-gate. M.sub.6b-source can be connected to GND. M.sub.7-drain can be connected to M.sub.5-source. M.sub.7-gate can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.5-drain, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain. M.sub.7-source can be connected to GND. M.sub.8-drain can be connected to M.sub.6-source. M.sub.8-gate can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.8-source can be connected to GND. M.sub.9-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.4-gate, M.sub.10-drain, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.9-gate can be connected to V.sub.DD. M.sub.9-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.5-drain, M.sub.10-source, and M.sub.5b-drain. M.sub.10-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.4-gate, M.sub.11-drain, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.10-gate can be connected to GND. M.sub.10-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.5-drain, and M.sub.5b-drain. M.sub.11-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.4-gate, M.sub.12-drain, M.sub.6b-drain, and M.sub.6-drain. M.sub.11-gate can be connected to CLK. M.sub.11-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.5-drain, M.sub.12-source, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain. M.sub.12-drain can be connected to data output QN, data output Q, M.sub.6-gate, M.sub.8-gate, M.sub.4-source, M.sub.9-drain, M.sub.10-drain, M.sub.11-drain, M.sub.4-gate, M.sub.6b-drain, and M.sub.6-drain. M.sub.12-gate can be connected to CLK. M.sub.12-source can be connected to M.sub.1-source, M.sub.2-source, M.sub.5-gate, M.sub.7-gate, M.sub.11-source, M.sub.5-drain, M.sub.3-source, M.sub.9-source, M.sub.10-source, and M.sub.5b-drain.
[0163]
TABLE-US-00003 TABLE 3 Function Table for Latch Topologies of FIGS. 29-32 Scenarios Operations VDD = 1; CLK = 1 Q follows D VDD = 1; CLK = 0 Q holds VDD = 0 Q = 0 VDD = 0.fwdarw.1; CLK = 0 Q restores to stored state (NV-Latch)
[0164]
[0165]
[0166] In
[0167] The pseudo-floating 0 has three major effects. First, functionality will stay correct with proper noise shielding. This is because a short period of ns in time of being pseudo-floating will not have the state corrupted if external coupling noise is properly isolated. For example, most standard embedded dynamic random access memory (DRAM) cells have a retention time of a few microseconds at the internal floating MOSFET gate. After the polarization switching finishes in the order of ns or sub-ns, this pseudo-floating 0 becomes a steady 0 connecting to GND. Second, endurance will improve. Although existing research has not yet found out a fundamental bottleneck in improving the endurance or aging effects of ferroelectric materials, existing ferroelectric materials degrade faster in terms of number of full-swing switching cycles than CMOS transistors. The way above of slower polarization switching helps to reduce the number of full-swing switching activities, which improves the endurance of FeFETs. Third, delay and energy performance may also improve. First, considering the conventional volatile CMOS latch in
[0168]
[0169] The latch topology shown in
[0170] Referring to
[0171] In at least one embodiment, M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.7, and M.sub.8 are MOSFETs. In at least one embodiment, M.sub.5 and M.sub.6 are FeFETs 102. M1-drain can be connected to data input D. M.sub.1-gate can be connected to CLK. M.sub.1-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.2-drain can be connected to data input DN. M.sub.2-gate can be connected to M.sub.1-gate. M.sub.2-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.1-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.3-drain can be connected to V.sub.DD. M.sub.3-gate can be connected to M.sub.5-gate, M.sub.1-source, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.3-source can be connected to M.sub.5-drain. M.sub.4-drain can be connected to V.sub.DD. M.sub.4-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.1-source. M.sub.4-source can be connected to M.sub.6-drain. M.sub.5-drain can be connected to M.sub.3-source. M5-gate can be connected to M.sub.1-source, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.5-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.1-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.6-drain can be connected to M.sub.4-source. M.sub.6-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.1-source, and M.sub.4-gate. M.sub.6-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.1-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.7-drain can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.1-source, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.7-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.1-source, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.7-source can be connected to GND. M.sub.8-drain can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.1-source, M.sub.8-gate, M.sub.6-gate, and M.sub.4-gate. M.sub.8-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.5-source, M.sub.2-source, M.sub.7-gate, M.sub.7-drain, data output Q, data output QN, M.sub.6-source, M.sub.8-drain, M.sub.1-source, M.sub.6-gate, and M.sub.4-gate. M.sub.8-source can be connected to GND.
[0172] Referring to
[0173] In at least one embodiment, M.sub.1, M.sub.2, M.sub.3, M.sub.4, M.sub.9, and M.sub.10 are MOSFETs. In at least one embodiment, M.sub.5, M.sub.6, M.sub.7, and M.sub.8 are FeFETs 102. M.sub.1-drain can be connected to data input D. M.sub.1-gate can be connected to CLK. M.sub.1-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.2-drain can be connected to data input DN. M.sub.2-gate can be connected to M.sub.1-gate. M.sub.2-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.1-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.3-drain can be connected to V.sub.DD. M.sub.3-gate can be connected to M.sub.5-gate, M.sub.1-source, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.3-source can be connected to M.sub.5-drain. M.sub.4-drain can be connected to V.sub.DD. M.sub.4-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.1-source, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.4-source can be connected to M.sub.6-drain. M.sub.5-drain can be connected to M.sub.3-source. M.sub.5-gate can be connected to M.sub.1-source, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.5-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.1-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.6-drain can be connected to M.sub.4-source. M.sub.6-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.1-source, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.6-source can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.1-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.7-drain can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.1-source, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.7-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.1-source, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.10-gate. M.sub.7-source can be connected to M.sub.9-drain. M.sub.10-drain can be connected to M.sub.8-source. M.sub.10-gate can be connected to M.sub.5-gate, M.sub.3-gate, M.sub.2-source, M.sub.7-gate, M.sub.9-gate, M.sub.5-source, M.sub.6-source, data output Q, M.sub.6-gate, M.sub.4-gate, M.sub.7-drain, M.sub.8-drain, data output QN, M.sub.8-gate, and M.sub.1-source. M.sub.10-source can be connected to GND.
[0174] In terms of the physical layout design, the overhead of the FeFETs 102 in embodiments of the latches of
[0175]
[0176]
[0177]
[0178]
[0179] In some embodiments an improved DFF 120 can be generated by replacing any one or combination of its master latch and slave latch with an embodiment of the latch 118, 122 disclosed herein.
[0180] The master latch 122 can be connected to the slave latch 118 via S.sub.GATE1 and S.sub.GATE2. For example, the master latch 122 can have a first master transmission gate M.sub.GATE1, a first master inverter, M.sub.INV1, a second master inverter, M.sub.INV2, and a second master transmission gate, M.sub.GATE2. The input of M.sub.GATE1 can be connected to a data input signal, D. The output of M.sub.GATE1 can be connected to the input of M.sub.INV1 and the input of S.sub.GATE1. The input of M.sub.INV1 can be connected to the output of M.sub.GATE1. The output of M.sub.INV1 can be connected to the input of M.sub.INV2 and the input of S.sub.GATE2. The input of M.sub.INV2 can be connected to the output of M.sub.INV1. The output of M.sub.INV2 can be connected to the input of M.sub.GATE2. The input of M.sub.GATE2 can be connected to the output of M.sub.INV2. The output of M.sub.GATE2 can be connected to the input of M.sub.GATE1 and the output of M.sub.INV1. From this topology, the master latch 122 and slave latch 118 can be connected with switches.
[0181]
[0182] The master latch 122 can be connected to the slave latch 118 via S.sub.INV1 and S.sub.INV2. For example, the master latch 122 can have a first master transmission gate M.sub.GATE1, a first master inverter, M.sub.INV1, a second master inverter, M.sub.INV2, and a second master transmission gate, M.sub.GATE2. The input of M.sub.GATE1 can be connected to a data input signal, D. The output of M.sub.GATE1 can be connected to the input of M.sub.INV1 and the input of S.sub.INV1. The input of M.sub.INV1 can be connected to the output of M.sub.GATE1. The output of M.sub.INV1 can be connected to the input of M.sub.INV2 and the input of S.sub.INV2. The input of M.sub.INV2 can be connected to the output of M.sub.INV1. The output of M.sub.INV2 can be connected to the input of M.sub.GATE2. The input of M.sub.GATE2 can be connected to the output of M.sub.INV2. The output of M.sub.GATE2 can be connected to the input of M.sub.GATE1 and the output of M.sub.INV1. From this topology, the master latch 122 and slave latch 118 can be connected with clocked inverters for isolation.
[0183]
[0184] The master latch 122 can be connected to the slave latch 118 via S.sub.INV. For example, the master latch 122 can have a first master inverter M.sub.INV1, a second master inverter, M.sub.INV2, a third master inverter, M.sub.INV3, and a master transmission gate, M.sub.GATE. The input of M.sub.INV1 can be connected to a data input signal, D. The output of M.sub.INV1 can be connected to the input of M.sub.INV2. The input of M.sub.INV2 can be connected to the output of M.sub.INV1. The output of M.sub.INV2 can be connected to the input of M.sub.INV3 and the input of S.sub.INV. The input of M.sub.INV3 can be connected to the output of M.sub.INV2. The output of M.sub.INV3 can be connected to the input of M.sub.GATE. The input of M.sub.GATE can be connected to the output of M.sub.INV3. The output of M.sub.GATE can be connected to the input of M.sub.INV2 and the output of M.sub.INV1.
[0185] With reference to
[0186] The setup and hold time of the DFF 120 with the topology in
[0187]
[0188]
[0189] It is also noted that embodiments of the DFF 120 has lower backup and restore speed than conventional DFFs. This can be due to the adoption of low-power (high V.sub.TH) CMOS transistors to achieve low leakage current for low-power IoT applications. For example, conventional NCFET based DFFs have around 0.12 W static leakage power when operating at 0.8V supply, while the embodiments of the DF 120 can have less than 0.2 nW at 0.8V. The backup and restore speed of embodiments of the DFF 120 are sufficiently fast for most if not all scenarios, as charging and discharging the supply network on the chip following a power failure and recovery usually takes much longer time than a few nanoseconds. The adoption of high V.sub.TH MOSFETs in the main signal routes can also improve the reliability during backup and restore operations.
[0190]
[0191] Additional advantages of embodiments of the DFF 120 over some conventional DFF devices can stem from the fact that the conventional DFF devices may be two-terminal devices, wherein the change of their memory state requires a static current or voltage across them for a certain period of time. Such static current, especially considering the widened time window for write operations due to the impact of device variations, significant amount of energy will be consumed by them. Furthermore, the great scalability, low-voltage operation, high ON-OFF ratio, and the unique external-control-free feature, highlight additional advantage of embodiments of the DFF 120.
[0192] Given an FEFET 102 structure and the ferroelectric material, the tunable FeFET design parameter is the ferroelectric layer thickness T. During device optimizations, the first concern is the retention time. For FeFET memory devices, it depends on the energy barrier between the two polarization states. Increasing T.sub.FE can helps increasing the coercive voltage that is required to change the polarization. However, it results in a larger minimum required supply voltage, which indicates more energy consumption each time the polarization is switched.
[0193] It is noted that the restore functionality of the embodiments of the latches 118, 122 and DFFs 120 depends on the difference of the sensed resistance from Q/QN to GND or V.sub.DD, which indicates that the sensitivity of the sensed resistance may be critical for yield. For simplicity, only the sensed resistance to GND, i.e. RQ2GND, was analyzed. For en embodiment of the DFF 120, the sensed resistance can be defined as the sum of the series FeFET drain-source resistance RFeFET and the NMOS drain-source resistance RCMOS. When storing a different latch bit information, the key difference in the initial sensed resistance, without considering process non-idealities, varies in RFeFET. As a result, the ratio of RQ2GND between the two branches in the latch can be:
[0194] A smaller will lead to more stable restore operation and is more noise-resistant. A small RCMOS or a large RFeFET, 0 is thus helpful. Considering the orders of difference in the ON-OFF resistance of RFeFET, the approximation in the equation above is rather safe. For this purpose, T.sub.FE is set to be 8 nm so as to provide large ON-OFF state resistance while enabling low-voltage operation. Since the degradation of F can be easily caused by the variation of the NMOS initial resistance, RCMOS, 0 and RCMOS, 1, analysis should be carried out. This is especially important for designs of the DFF 120, because another parallel branch (see M.sub.5b and M.sub.6b) is affecting F, too. The difference in RCMOS, 0 and RCMOS, 1 mainly comes from device size mismatch and threshold voltage V.sub.TH variation V.sub.TH. By manually adding an opposite in-series gate driving voltage to the gate, as shown in
[0195] It is also interesting to find out, that the variation impact is independent on the supply voltage within the given range of 0.5V to 1.0V. This is because of the relatively long rising time for the supply voltage to recover, and the fact that the initial restore trend is almost equal for scenarios with different V.sub.DD. To provide a small F, the latch is designed in a way that all CMOS transistors have a higher V.sub.TH than the bottom two transistors connecting to FeFETs (e.g., M.sub.7 and M.sub.8). By doing this, the following goals could be achieved: (i) The resistance of M.sub.7 and M.sub.5b, or that of M.sub.8 and M.sub.th, plays a less significant role than that of FeFETs, as M.sub.7 is in series with the FeFET, and M.sub.5b is in parallel with the FeFET. This will help built the correct rising trend of Q and QN when V.sub.DD starts to recover. (ii) Static leakage current of the latch will not increase. This can be guaranteed by a proper FeFET design with a high OFF-state resistance. Given a certain ferroelectric material and transistor structure, this OFF-state resistance could be tuned by varying T.sub.FE and the width of FeFET 102. The large inherent ON-OFF resistance ratio will help to reduce the impact of FeFET variation.
[0196] Embodiments of the DFF 120 could be strongly complementary to existing power-gating approaches in both low and high-performance systems. In aggressive, high speed systems using fine-grained, low-latency power-gating techniques, the ability to power-gate stateful units up to and including entire processor cores within a handful of cycles would both expand the scope of what can be power-gated and simplify design constraints. While the impact of no need for backup and restore control for power-gating is still not yet fully explored, it is promising to open up new possibilities for further energy savings and architecture optimizations due to the reduced control complexity. On the energy-harvesting end of the spectrum, one apparent benefit is the reduced backup and restore energy consumption and latency, which improves the utilization of harvested energy for the purpose computation. The intrinsic non-volatility ensures no missing backup without the need for backup control, leading to prevention of roll-back operations in the computation progress. While there are already works on nonvolatile processor optimizations, further architecture-level optimizations would be useful to capture the intrinsic non-volatility of FeFET flip-flops. Meanwhile, it has been shown that the recovery time in NVPs after a power emergency are sometimes dominated by the recovery of analog components, such as ensuring PLL stability. While this limits the impact of the rapid recovery time that NC-DFFs have in such systems, their rapid, completely distributed and low energy backup properties may allow power gating of data path and other digital components fast enough to divert energy during shorter or less severe power emergencies in order to preserve analog functionality, using embodiments of the DFF 120F cycle-latency (at NVP frequencies) power gating potential to shave microseconds off recovery times.
[0197] Embodiments of the NMV device 100 can be configured as a memory cell 124. Embodiments of the memory cell 124 can be configured with a 2-transistor FeFET 102 topology between the Wordline and the Readline (2T-memory cell 124) or a 3-transistor FeFET 102 topology between the Wordline and Readline (3T-memory cell 124). Embodiments of the memory cell 124 can facilitate an improved memory access method.
[0198] For example, embodiments of the memory cell 124 can include at least one FeFET 102 to provide intrinsic non-volatility, compatibility with commercial CMOS processes, both high ON-state current and low OFF-state current, and/or merged logic-memory functionality, which can facilitate convenient writing and nondestructive reading for the memory cell 124. Embodiments of the memory cell 124 can have high energy-efficiency and high write speed, along with improved performance and energy versus latency tradeoffs for writes. Embodiments of the memory cell 124 can support voltage-mode sensing for read access, which can broaden design space flexibility in support of different application scenarios.
[0199] As noted herein, nonvolatile memory arrays can be used to reduce or eliminate static leakage power in embedded memories by completely shutting down the power supply while retaining the stored data and computation progress. Conventional nonvolatile devices can be limited by requiring the write operation to depend on the voltage change at the FeFET gate only and not concurrently at the FeFET drain and source. This can require a doubled gate driving voltage range to set the memory state, resulting in multi-supply overheads and loss of energy efficiency. In addition, a voltage-mode read is not supported with conventional topologies for nonvolatile devices, causing high design overheads for read access in some scenarios due to bit-line current sensing and voltage clamping.
[0200]
[0201] For conventional logic gates, hysteresis should be strictly controlled or minimized to comply with the logic operation. On the contrary, it is intriguing to use the hysteresis for low-power NVM applications.
[0202]
[0203] The two nonvolatile G.sub.DS states in
[0204] With proper MOSFET work function engineering and ferroelectric material design that matches the MOSFET properties, e.g. the gate capacitance, it is possible to locate the FeFET I-V hysteresis window around zero V.sub.GS with embodiments of the FeFET 102. By tuning T.sub.FE, the hysteresis width could also be optimized to work under a proper supply voltage, as shown in
[0205] Embodiments of the FeFET 102 can have integrated the NVM storage and the logic transistor operating as a memory state amplifying reader. Such integration not only provides the opportunity to design a simplified low-power sensing scheme, but also opens up new space for future memory-oriented computing.
[0206] The polarization switching can be accomplished by applying a positive or negative voltage across the ferroelectric layer 114. Different from the state change in resistive memory devices, no static DC current is consumed for embodiments of the FeFET 102 (biased with V.sub.DS=0V). Furthermore, when considering the resistive memory device variations of required write pulse duration, even more energy could be saved.
[0207] It should be noted that the ferroelectric material in FeFETs could be the same as that in ferroelectric random access memory (FeRAM) devices, leading to similar memory features of retention time, endurance, etc. Yet, the FeFET memory read operation is non-destructive, which outperforms FeRAM. In addition, FeFET is fundamentally superior to FeRAM with better distinguishability and access interface.
[0208] Referring to
[0209] Some embodiments can include a plurality of 2T-memory cells 124. For example, a memory cell array 126 can include a first 2T-memory cell 124, a second 2T-memory cell 124, a third 2T-memory cell 124, etc. In at least one embodiment, the memory cell array 126 can include a first 2T-memory cell 124, a second 2T-memory cell 124, a third 2T-memory cell 124, a fourth 2T-memory cell 124, a fifth 2T-memory cell 124, a sixth 2T-memory cell 124, a seventh 2T-memory cell 124, and an eighth 2T-memory cell 124. The memory cell array 126 can have a first BL, BL1, a second BL, BL2, a third BL, BL3, and a fourth BL, BL4. The memory cell array 126 can have a first WLW, WLW1, a second WLW, WLW2, a first WLR, WLR1, and a second WLR, WLR2. Each memory cell 124 can have a T.sub.1 and a T.sub.2, wherein T.sub.1 is a MOSFET and T.sub.2 is a FeEFT 102. For example, the first 2T-memory cell 124 can have a first T.sub.1 and a first T.sub.2. The second 2T-memory cell 124 can have a second T.sub.1 and a second T.sub.2. The third 2T-memory cell 124 can have a third T.sub.1 and a third T.sub.2. The fourth 2T-memory cell 124 can have a fourth T.sub.1 and a fourth T.sub.2. The fifth 2T-memory cell 124 can have a fifth T.sub.1 and a fifth T.sub.2. The sixth 2T-memory cell 124 can have a sixth T.sub.1 and a sixth T.sub.2. The seventh 2T-memory cell 124 can have a seventh T.sub.1 and a seventh T.sub.2. The eighth 2T-memory cell 124 can have an eighth T.sub.1 and a eighth T.sub.2. Each of WLW1 and WLW2 can be configured to receive and/or transmit a write signal for write operations. Each of WLR1 and WLR2 can be configured to receive and/or transmit a read signal for read operations.
[0210] For the first 2T-memory cell 124, first cell T.sub.2-drain can be connected to BL1 and WLW1. First cell T.sub.2-gate can be connected to WLW1. First cell T.sub.2-source can be connected to first cell T.sub.1-drain. First cell T.sub.1-gate can be connected to WLR1 and BL1. First cell T.sub.1-source can be connected to GND. For the second 2T-memory cell 124, second cell T.sub.2-drain can be connected to BL2 and WLW1. Second cell T.sub.2-gate can be connected to WLW1. Second cell T.sub.2-source can be connected to second cell T.sub.1-drain. Second cell T.sub.1-gate can be connected to WLR1 and BL2. Second cell T.sub.1-source can be connected to GND. For the third 2T-memory cell 124, third cell T.sub.2-drain can be connected to BL3 and WLW1. Third cell T.sub.2-gate can be connected to WLW1. Third cell T.sub.2-source can be connected to third cell T.sub.1-drain. Third cell T.sub.1-gate can be connected to WLR1 and BL3. Third cell T.sub.1-source can be connected to GND. For the fourth 2T-memory cell 124, fourth cell T.sub.2-drain can be connected to BL4 and WLW1. Fourth cell T.sub.2-gate can be connected to WLW1. Fourth cell T.sub.2-source can be connected to fourth cell T.sub.1-drain. Fourth cell T.sub.1-gate can be connected to WLR1 and BL4. Fourth cell T.sub.1-source can be connected to GND. For the fifth 2T-memory cell 124, fifth cell T.sub.2-drain can be connected to BL1 and WLW2. Fifth cell T.sub.2-gate can be connected to WLW2. Fifth cell T.sub.2-source can be connected to fifth cell T.sub.1-drain. Fifth cell T.sub.1-gate can be connected to WLR2 and BL1. Fifth cell T.sub.1-source can be connected to GND. For the sixth 2T-memory cell 124, sixth cell T.sub.2-drain can be connected to BL2 and WLW2. Sixth cell T.sub.2-gate can be connected to WLW2. Sixth cell T.sub.2-source can be connected to sixth cell T.sub.1-drain. Sixth cell T.sub.1-gate can be connected to WLR2 and BL2. Sixth cell T.sub.1-source can be connected to GND. For the seventh 2T-memory cell 124, seventh cell T.sub.2-drain can be connected to BL3 and WLW2. Seventh cell T.sub.2-gate can be connected to WLW2. Seventh cell T.sub.2-source can be connected to seventh cell T.sub.1-drain. Seventh cell T.sub.1-gate can be connected to WLR2 and BL3. Seventh cell T.sub.1-source can be connected to GND. For the eighth 2T-memory cell 124, eighth cell T.sub.2-drain can be connected to BL4 and WLW2. Eighth cell T.sub.2-gate can be connected to WLW2. Eighth cell T.sub.2-source can be connected to eighth cell T.sub.1-drain. Eighth cell T.sub.1-gate can be connected to WLR2 and BL4. Eighth cell T.sub.1-source can be connected to GND.
[0211]
[0212] Embodiments of the memory cell array 126 can operate with a row-wise read.
[0213] If current-sensing read is adopted, the bit line voltage V.sub.BL should be fixed, and the current from the bit line to the ground through the cell in the selected row can be sensed by a current sense amplifier, similar to existing resistive memory array sensing schemes. This can help to reduce the sensing latency by avoiding charging and discharging the long bit-line parasitic capacitance for a large-size array. The capability of supporting both sensing modes provides more case-to-case design flexibility.
[0214]
[0215]
[0216] Embodiments of a 3T-memory cell 124 can provide additional design flexibility in certain scenarios.
[0217] The 3T-memory cell 124 having a two-bit line topology can have a first transistor, T.sub.1, a second transistor, T.sub.2, a third transistor T.sub.3, a first bit line, BLW, a second bit line, BLR, a WLW, a WLR, and a Wordline-Readline, WLRL. T.sub.1 and T.sub.3 can be MOSFETs. T.sub.2 can be a FeFET 102. T.sub.1 can have a T.sub.1-source, a T.sub.1-gate, and a T.sub.1-drain. T.sub.2 can have a T.sub.2-source, a T.sub.2-gate, and a T.sub.2-drain. T.sub.3 can have a T.sub.3-source, a T.sub.3-gate, and a T.sub.3-drain. T.sub.1-drain can be connected to T.sub.2-gate. T.sub.1-gate can be connected to WLW. T.sub.1-source can be connected to BLW. T.sub.2-drain can be connected to T.sub.3-source. T.sub.2-gate can be connected to T.sub.1-drain. T.sub.2-source can be connected to WLRW. T.sub.3-drain can be connected to BLR. T.sub.3-gate can be connected to WLR. T.sub.3-source can be connected to T.sub.2-drain. Any one or combination of BLW, WLW, and WLRW can be connected to GND. WLR can be connected to V.sub.DD.
[0218] The 3T-memory cell 124 can have one write-access N-type MOS transistor T.sub.1 controlled by the write-access word line WLW, one read-access N-type MOS transistor T.sub.3 controlled by the read-access word line WLR, and to storage N-type FeFET T.sub.2 connecting to the wordline WLRW for both read and write. The cell 124 uses two bit lines: BLR for read and BLW for write. In power-OFF and idle modes, all word lines and bit lines could be safely grounded. Both voltage sensing and current sensing could be used to perform read. In the voltage-sensing read, T.sub.3 can be turned ON, and WLRW set to GND. The pre-charged V.sub.BLR will remain almost unchanged with an OFF-state T.sub.2 or drop quickly to GND with an ON-state T.sub.2. A voltage thresholding of V.sub.BLR could provide the sensing result for a voltage-mode sensing scheme. In the current-mode sensing scheme, V.sub.BLR can be fixed and T.sub.3 turned ON. Thus, the current delivered by the cell can be sensed at the bit line, providing another meaningful option for energy-delay optimization in a larger memory array.
[0219] The 3T-memory cell 124 having a single-bit line topology can have a first transistor, T.sub.1, a second transistor, T.sub.2, a third transistor T.sub.3, a bit line, BL, a WLW, a WLR, and a WLRL. T.sub.1 and T.sub.3 can be MOSFETs. T.sub.2 can be a FeFET 102. T.sub.1 can have a T.sub.1-source, a T.sub.1-gate, and a T.sub.1-drain. T.sub.2 can have a T.sub.2-source, a T.sub.2-gate, and a T.sub.2-drain. T.sub.3 can have a T.sub.3-source, a T.sub.3-gate, and a T.sub.3-drain. T.sub.1-drain can be connected to T.sub.2-gate. T.sub.1-gate can be connected to WLW. T.sub.1-source can be connected to BL. T.sub.2-drain can be connected to T.sub.3-drain. T.sub.2-gate can be connected to T.sub.1-drain. T.sub.2-source can be connected to WLRW. T.sub.3-drain can be connected to T.sub.2-drain. T.sub.3-gate can be connected to WLR. T.sub.3-source can be connected to BL.
[0220]
[0221]
[0222] For fair comparison, no negative supply was used. For the conventional cell designs, the use of negative supply voltage of V.sub.DD was prevented by equally shifting up all supply and biasing voltages by V.sub.DD, as shown in
[0223] The write energy is the average energy consumed to write 1 and 0 from a different prior state. The write operation latency covers a different period of time between the embodiments of the memory cell 124 and conventional cell designs. For embodiments of the For the memory cell 124 that adopt two-phase write, it is the sum of latency in writing 0 and 1. For the conventional cell designs, the write operation latency is defined as the maximum latency to write 0 and write 1.
[0224]
[0225] It should be noted that, the write latency was based on set as 0.1. The energy and latency as a function of are provided in
[0226] The current-sensing read performance was not simulated as it strongly depends on the current sense amplifier design. Therefore, only the voltage-sensing read operations were evaluated. The read operation energy is the average energy consumed to read 1 and 0. As reading 1 does not noticeably change the bit line voltage, the read operation latency is actually equal to the latency for the read of 0, which is defined as the delay from the effective word line triggering point (with 50% voltage change) to the point when the read bit line voltage has reduced by 150 mV. Practically, a voltage difference of 150 mV could be sensed with a voltage-mode amplifier that does not require a high gain.
[0227]
[0228] Table 4 summarizes the benchmarking results, where the comparison of embodiment so of the memory cell's 124 access performance, density, peripheral circuitry requirement is displayed. It is also interesting to consider the OFF-to-Ready energy, which is the energy needed to wake up a cell array 126 from completely OFF state to the idle state ready for read and write. With the 2T topology, considering some idle-state biasing voltage settings are non-zero, the memory controller has to raise its voltage level accordingly and thus consumes extra energy. Embodiments of the 3T topology can operate with the largest supply voltage range, and does not require an extra supply voltage of V.sub.DD/2 or 2V.sub.DD, making it a good fit in scenarios when multi-supply is not available.
TABLE-US-00004 TABLE 4 Comparison of a Conventional Memory Cell and Embodiments of The Disclosed Memory Cells 124 Specifications Conv. Cell 2T-Topology 3T-Topology Number of transistors 2 2 3 Low voltage operation No Yes Yes Write energy Medium Low Low Write speed.sup.& Medium High High Current-mode read speed.sup.# High High High Current-mode read energy.sup.# Low Low Low Voltage-mode read speed High High Voltage-mode read energy Low Low OFF-to-Ready energy High Medium Low Additional supply voltage 2VDD Approx. VDD Not Needed .sup.&Write speed is compared based on the similar write energy consumption; .sup.#Current-mode read speed and energy are roughly evaluated based on the amount of sensed current in the OFF state and the ON state
[0229] Embodiments of the NVM device 100 can be configured as a 4T-topology (4T) B&R circuitry 116. For example, the B&R circuitry 116 can include only four transistors. This can be done to reduce area overhead. Some embodiments can include an improved DFF 120 by incorporating an embodiment of the 4T B&R circuitry 116. With embodiments of the 4T B&R circuitry 116, the transistor number of B&R circuitry is lowered, and the backup control can be embedded into the supply voltage modulation with lowered routing cost. The energy-delay product overhead in the normal-mode operation can be below 5%. Embodiments of the DFF 120 with such a 4T B&R circuitry 116 can provide area- and energy-efficient nonvolatile computing for power-gating and energy-harvesting applications.
[0230] Power gating for idle digital circuits is an effective low-power design approach to reducing the leakage power by shutting down the supply. This can be a useful for both portable and server processors whose design optimizations often get tangled up with the battery life and the thermal limit, respectively. In practice, power-gated DFF states need to be saved in nonvolatile memories.
[0231] One key optimization for DFF backup and restore operations can be to focus on lowering the consumed energy. Another key optimization for DFFs can be to reduce the area overhead. This can have a significant impact in modern processors where complex pipelining logic and sometimes large register cache files are already adopted based on many flip-flops. Embodiments of the 4T B&R circuitry 116 and/or DFF 120 have a reduced the area overhead. In addition, the backup control is embedded into the supply voltage modulation, which reduces the routing cost since there is no need for an extra backup control signal.
[0232] While FeFETs can be designed hysteresis-free in I.sub.DV.sub.G to comply with the conventional logic gate switching style, embodiments of the B&R circuitry 116 and/or the DFF 120 can utilize the FeFET 102 characteristics of I.sub.DV.sub.G hysteresis.
[0233]
[0234] The 4T B&R circuit 116 can further include a first branch 101 and a second branch 103. The first branch 101 can include M.sub.1, M.sub.3, and GND. The second branch 103 can include M.sub.2, M.sub.4, and GND. Depending on the inputs, either the first branch 101 or the second branch 103 operates as a backup branch or a restore branch. For example, when the first branch 101 operates as a backup branch, the second branch 103 operates as a restore branch. When the first branch 101 operates as a restore branch, the second branch 103 operates as a backup branch. Particular note should be made to the cross-coupled circuit connection between M.sub.3 and the second branch 103 and M.sub.4 and the first branch 101.
[0235] In some embodiments, the B&R circuit 116 can be connected to a slave latch 118. (See
[0236] In at least one embodiment, M.sub.1 and M.sub.2 are MOSFETs. In at least one embodiment, M.sub.3 and M.sub.4 are FeFETs 102. M.sub.1-drain can be connected to M.sub.3-source. M.sub.1-gate can be connected to a restore signal input signal and M.sub.2-gate. M.sub.1-source can be connected to GND. M.sub.2-drain can be connected to M.sub.4-source. M.sub.2-gate can be connected to M.sub.1-gate. M.sub.3-drain can be configured to be connected to a slave latch 118, which can be via the first branch 101. M.sub.3-drain can be connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-gate, and to the second branch 103. M.sub.3-gate can be connected to M.sub.4-gate, M.sub.4-drain, M.sub.3-drain, and to the second branch 103. M.sub.3-source can be connected to M.sub.1-drain. M.sub.4-drain can be configured to be connected to the slave latch 118, which can be via the second branch 103. M.sub.4-drain can be connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-gate, and to the first branch 103. M.sub.4-gate can be connected to M.sub.3-gate, M.sub.3-drain, M.sub.4-drain, and to the first branch 103. M.sub.4-source can be connected to M.sub.2-drain.
[0237] Referring to
[0238] The master latch 122 can have a first master inverter M.sub.INV1, a second master inverter, M.sub.INV2, a third master inverter, M.sub.INV3, and a master transmission gate, M.sub.GATE. The input of M.sub.INV1 can be connected to a data input signal, D. The output of M.sub.INV1 can be connected to the input of M.sub.INV2. The input of M.sub.INV2 can be connected to the output of M.sub.INV1. The output of M.sub.INV2 can be connected to the input of M.sub.INV3. The input of M.sub.INV3 can be connected to the output of M.sub.INV2. The output of M.sub.INV3 can be connected to the input of M.sub.GATE. The input of M.sub.GATE can be connected to the output of M.sub.INV3. The output of M.sub.GATE can be connected to the input of M.sub.INV2 and the output of M.sub.INV1.
[0239] The slave latch 118 can have a first slave inverter, S.sub.INV1, a second slave inverter, S.sub.INV2, a third slave inverter, S.sub.INV3, and a slave transmission gate, S.sub.GATE. The input of S.sub.INV1 can be connected to the output of M.sub.INV2. The input of S.sub.INV2 can be connected to the output of S.sub.INV1. The output of S.sub.INV2 can be connected to the input of S.sub.INV3 and to a data output Q. The input of S.sub.INV3 can be connected to the output of S.sub.INV2. The output of S.sub.INV3 can be connected to the input of S.sub.GATE. The output of S.sub.GATE can be connected to the input of S.sub.INV2 and the output of S.sub.INV1.
[0240] A clock driver, CLK can be used to generate an in-phase clock signal, c, and opposite-phase clock signal, cn, for M.sub.INV1, M.sub.GATE, S.sub.INV1, and/or S.sub.GATE. Embodiments of the CLK can include a first clock inverter, CLK.sub.INV1, having an output connected to an input of a second clock inverter, CLK.sub.INV2. CLK.sub.INV1 can be configured to generate cn. CLK.sub.INV2 can be configured to generate c. Each of M.sub.GATE and S.sub.GATE can be a gate circuit for transmitting or blocking the output signal from the master latch 122 or slave latch 118, respectively, in response to the clock signal from CLK.
[0241] M.sub.3-drain can be connected to the output of S.sub.GATE, the output of S.sub.INV1, and the input of S.sub.INV2. For example, the first branch 101 can be connected to the output of S.sub.GATE, the output of S.sub.INV1, and the input of S.sub.INV2. M.sub.4-drain can be connected to the input of S.sub.INV3, the output of S.sub.INV2, and data output Q. For example, the second branch 103 can be connected to the input of S.sub.INV3, the output of S.sub.INV2, and data output Q.
[0242] In some embodiments, in the OFF mode, the voltage supply and all inputs can be grounded, and the FeFETs 102 (M.sub.3 and M.sub.4) stay stable with either positive or negative polarization. In the NORMAL mode, the restore can be grounded and the two N-type MOS transistors T.sub.1 and T.sub.2 can be turned OFF, so the DFF 120 operates like a conventional DFF. The normal-mode supply voltage can be adjusted dynamically for the best trade-off between C-to-Q delay and energy. The FeFET device parameters, including T.sub.FE, however, a may not be adjustable for a different hysteresis window width after fabrication. Therefore, in the normal-mode, the supply voltage can be designed to stay safely within the FeFET hysteresis window to avoid unnecessary FeFET polarization switching. In the backup mode, the restore input remains grounded, and the supply voltage is raised beyond the FeFET hysteresis edge, enabling polarization switching if a different DFF state was saved in the FeFETs 102 (M.sub.3 and M.sub.4).
[0243]
[0244] Once T.sub.FE is fixed, the DFF 120 has the minimum required V.sub.DD to carry out successful polarization switching in the backup mode, and the maximum V.sub.DD to avoid polarization switching in the normal mode. These two V.sub.DD levels are similar in magnitude due to the steep switching hysteresis edges.
[0245] Conventional DFF devices need four extra transistors to isolate the B&R circuitry and the slave latch, so the supply voltage in the normal mode can be higher, as compared to embodiments of the DFF 120 disclosed herein. For fair comparison, the same FeFETs were used in both an embodiment of the DFF 120 and a conventional DFF to conduct an analysis. Therefore, when the normal-mode supply voltage is lower than that in the backup mode, both the conventional DFF and embodiments of the DFF 120 raise the supply voltage accordingly for backups. As will be shown, embodiments of the DFF 120 can re-use the supply voltage modulation unit without introducing other overheads.
[0246]
[0247]
[0248]
TABLE-US-00005 TABLE 5 Metric Comparisons of an Embodiment of the DFF 120 with Conventional DFF Devices Conventional Conventional Embodiment of the DFF DFF DFF 120 Number of B&R 2 or 4 8 4 transistors Normal-mode EDP 30%-50% <5% <5% overhead External B&R control Not needed Not needed Needed signals Backup and restore: fj, ns fj, ns fj, ns energy, speed Immunity to variation Medium High High and noise * Restore signal needed; Backup control is embedded into the supply signal.
[0249] Embodiments of the DFF 120 can reduce the area overhead of DFF by 50%, through harnessing the feature of logic-memory fusion in FeFETs. Embodiments of the DFF 120 consumes only fJ energy to accomplish the nonvolatile backup and restore operations within ns, with an energy-delay performance overhead below 5%.
[0250] It should be understood that modifications to the embodiments disclosed herein can be made to meet a particular set of design criteria. For instance, the number of or configuration of MOSFETs, FeFETs 102, DFFs 120, slave latches 118, master latches 122, memory cells 124, eyepieces 108, and/or other components or parameters may be used to meet a particular objective. In addition, any of the embodiments of the NVM devices 100 (e.g., B&R circuit 116, 4T B&R circuit 116, clave latch 118, master latch 122, DFF 120, memory cell 124, etc.) disclosed herein can be connected to other embodiments of the NVM devices 100 (e.g., B&R circuit 116, 4T B&R circuit 116, clave latch 118, master latch 122, DFF 120, memory cell 124, etc.) to generate a device.
[0251] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings of the disclosure. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternative embodiments may include some or all of the features of the various embodiments disclosed herein. For instance, it is contemplated that a particular feature described, either individually or as part of an embodiment, can be combined with other individually described features, or parts of other embodiments. The elements and acts of the various embodiments described herein can therefore be combined to provide further embodiments.
[0252] Therefore, it is the intent to cover all such modifications and alternative embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. Additionally, the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points. Thus, while certain exemplary embodiments of apparatuses and methods of making and using the same have been discussed and illustrated herein, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.
[0253] It should also be appreciated that some components, features, and/or configurations may be described in connection with only one particular embodiment, but these same components, features, and/or configurations can be applied or used with many other embodiments and should be considered applicable to the other embodiments, unless stated otherwise or unless such a component, feature, and/or configuration is technically impossible to use with the other embodiment. Thus, the components, features, and/or configurations of the various embodiments can be combined together in any manner and such combinations are expressly contemplated and disclosed by this statement. Thus, while certain exemplary embodiments of the NVM devices 100 have been shown and described above, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.