G11C11/221

CHARGE LEAKAGE DETECTION FOR MEMORY SYSTEM RELIABILITY

Methods, systems, and devices for charge leakage detection for memory system reliability are described. In accordance with examples as disclosed herein, a memory system may employ memory management techniques configured to identify precursors of charge leakage in a memory device, and take preventative action based on such identified precursors. For example, a memory system may be configured to perform a leakage detection evaluation for a memory array, which may include various biasing and evaluation operations to identify whether a leakage condition of the memory array may affect operational reliability. Based on such an evaluation, the memory device, or a host device in communication with the memory device, may take various preventative measures to avoid operational failures of the memory device or host device that may result from ongoing operation of a memory array associated with charge leakage, thereby improving reliability of the memory system.

POWER GATING IN A MEMORY DEVICE
20230113576 · 2023-04-13 ·

Methods, systems, and devices for power gating in a memory device are described for using one or more memory cells as drivers for load circuits of a memory device. A group of memory cells of the memory device may represent memory cells that include a switching component and that omit a memory storage element. These memory cells may be coupled with respective plate lines that may be coupled with a voltage source having a first supply voltage. Each memory cell of the group may also be coupled with a respective digit line that may be coupled with the load circuits. Respective switching components of the group of memory cells may therefore act as drivers to apply the first supply voltage to one or more load circuits by coupling a digit line with a plate line having the first supply voltage.

THIN FILM TRANSISTOR DECK SELECTION IN A MEMORY DEVICE
20230112259 · 2023-04-13 ·

Methods, systems, and devices for thin film transistor deck selection in a memory device are described. A memory device may include memory arrays arranged in a stack of decks formed over a substrate, and deck selection components distributed among the layers to leverage common substrate-based circuitry. For example, each memory array of the stack may include a set of digit lines of a corresponding deck, and deck selection circuitry operable to couple the set of digit lines with a column decoder that is shared among multiple decks. To access memory cells of a selected memory array on one deck, the deck selection circuitry corresponding to the memory array may each be activated, while the deck selection circuitry corresponding to a non-selected memory array on another deck may be deactivated. The deck selection circuitry, such as transistors, may leverage thin-film manufacturing techniques, such as various techniques for forming vertical transistors.

MEMORY CELL SENSING USING AN AVERAGED REFERENCE VOLTAGE
20230113652 · 2023-04-13 ·

Methods, systems, and devices for memory cell sensing using an averaged reference voltage are described. A memory device may generate the averaged reference voltage that is specific to operating conditions or characteristics. The averaged reference voltage thus may track variations in cell use and cell characteristics. The memory device may generate the averaged reference voltage by shorting together reference nodes to determine an average of values associated with the reference nodes. The reference nodes may be associated with a codeword, which may store values corresponding to the reference nodes. The codeword may be balanced or nearly balanced to include equal or nearly equal quantities of different logic values.

Single plate configuration and memory array operation

Methods, systems, and devices for a single plate configuration and memory array operation are described. A non-volatile memory array may utilize a single plate to cover a subset of the array. One or more memory cells of the subset may be selected by operating the plate and an access line of an unselected memory cell at a fixed voltage. A second voltage may be applied to an access line of the selected cell, and subsequently reduced to perform an access operation. Removing the applied voltage may allow for the memory cell to undergo a recovery period prior to a subsequent access operation.

Analog Non-Volatile Memory Device Using Poly Ferrorelectric Film with Random Polarization Directions
20220336478 · 2022-10-20 ·

A semiconductor device includes a ferroelectric field-effect transistor (FeFET), wherein the FeFET includes a substrate; a source region in the substrate; a drain region in the substrate; and a gate structure over the substrate and between the source region and the drain region. The gate structure includes a gate dielectric layer over the substrate; a ferroelectric film over the gate dielectric layer; and a gate electrode over the ferroelectric film.

Method of forming stacked ferroelectric planar capacitors in a memory bit-cell

A high-density low voltage ferroelectric (or paraelectric) memory bit-cell that includes a planar ferroelectric or paraelectric capacitor. The memory bit-cell comprises 1T1C configuration, where a plate-line is parallel to a word-line, or the plate-line is parallel to a bit-line. The memory bit-cell can be 1TnC, where ‘n’ is a number. In a 1TnC bit-cell, the capacitors are vertically stacked allowing for multiple values to be stored in a single bit-cell. The memory bit-cell can be multi-element FE gain bit-cell. In a multi-element FE gain bit-cell, data sensing is done with signal amplified by a gain transistor in the bit-cell. As such, higher storage density is realized using multi-element FE gain bit-cells. In some examples, the 1T1C, 1TnC, and multi-element FE gain bit-cells are multi-level bit-cells. To realize multi-level bit-cells, the capacitor is placed in a partially switched polarization state by applying different voltage levels or different time pulse widths at the same voltage level.

Reading scheme for multi-element gain ferroelectric memory bit-cell with plate-lines parallel to a bit-line and with individual switches on the plate-lines of the bit-cell

A memory is provided which comprises a capacitor including non-linear polar material. The capacitor may have a first terminal coupled to a node (e.g., a storage node) and a second terminal coupled to a plate-line. The capacitors can be a planar capacitor or non-planar capacitor (also known as pillar capacitor). The memory includes a transistor coupled to the node and a bit-line, wherein the transistor is controllable by a word-line, wherein the plate-line is parallel to the bit-line. The memory includes a refresh circuitry to refresh charge on the capacitor periodically or at a predetermined time. The refresh circuit can utilize one or more of the endurance mechanisms. When the plate-line is parallel to the bit-line, a specific read and write scheme may be used to reduce the disturb voltage for unselected bit-cells. A different scheme is used when the plate-line is parallel to the word-line.

Reducing duty cycle degradation for a signal path
11605416 · 2023-03-14 · ·

Methods, systems, and devices for reducing duty cycle degradation for a signal path are described. In some examples, a memory system may alternate a polarity of a signal line or signal path that includes a set of transistors during successive active periods of the memory system. In some cases, the memory device may include an inversion control component configured to operate the signal using either a first polarity or a second polarity. The inversion control component may receive an indication when the memory system enters an active period, and may accordingly alternate or the polarity of the signal path during successive active periods. In some examples, the signal path may be coupled with one or more output components which may uninvert signals from the signal path when the inversion control component has inverted the polarity of the signal path.

SELF-REFERENCE SENSING FOR MEMORY CELLS
20230071819 · 2023-03-09 ·

Methods, systems, and apparatuses for self-referencing sensing schemes are described. A cell having two transistors, or other switching components, and one capacitor, such as a ferroelectric capacitor, may be sensed using a reference value that is specific to the cell. The cell may be read and sampled via one access line, and the cell may be used to generate a reference voltage and sampled via another access line. For instance, a first access line of a cell may be connected to one read voltage while a second access line of the cell is isolated from a voltage source; then the second access line may be connected to another read voltage while the first access line is isolate from a voltage source. The resulting voltages on the respective access lines may be compared to each other and a logic value of the cell determined from the comparison.