G11C16/3422

Read disturb scan for unprogrammed wordlines

A memory device to perform a read disturb scan of unprogrammed memory cells. In one approach, a test read is performed on unprogrammed memory cells in a first memory block of a storage media (e.g., NAND flash) to provide a test result. Based on the test result, a portion of the unprogrammed cells for which a threshold voltage is above a predetermined voltage is determined. A determination is made whether the portion of the unprogrammed memory cells exceeds a predetermined limit. In response to determining that the portion exceeds the predetermined limit, data is moved from the first memory block to a second memory block of the storage media.

FLASH MEMORY STORAGE APPARATUS AND A BIASING METHOD THEREOF, WHICH CAN REDUCE A GATE INDUCED DRAIN LEAKAGE (GIDL) AND IMPROVE RELIABILITY OF MEMORY CELLS

A flash memory storage apparatus includes a memory cell array and a voltage generating circuit. The memory cell array includes at least one memory cell string coupled between a bit line and a source line and including memory cells; each memory cell is coupled to a corresponding word line. The voltage generating circuit is coupled to the memory cell array and configured to output a bias voltage to the word line. A first voltage is applied to a selected word line. A second voltage and a third voltage are applied to unselected second and third word lines, respectively. The first voltage is greater than the second voltage, and the second voltage is greater than the third voltage. The second word line and the third word line are located on two sides of the first word line. A biasing method of a flash memory storage apparatus is also provided.

THREE DIMENSIONAL STACKED NONVOLATILE SEMICONDUCTOR MEMORY
20220351778 · 2022-11-03 · ·

A three dimensional stacked nonvolatile semiconductor memory according to an example of the present invention includes a memory cell array comprised of first and second blocks. The first block has a first cell unit which includes a memory cell to be programmed and a second cell unit which does not include a memory cell to be programmed, and programming is executed by applying a program potential or a transfer potential to word lines in the first block after the initial potential of channels of the memory cells in the first and second cell units is set to a plus potential. In the programming, the program potential and the transfer potential are not applied to word lines in the second block.

High Accuracy Leakage Detection Through Low Voltage Biasing
20170316834 · 2017-11-02 ·

Techniques are presented for determining current leakage from a memory array or other circuit based on a low voltage path. For example, the technique can be applied to determine word line to word line leakage. By looking at a count for the clock used in regulating the low voltage output node, the amount of leakage can be determined. The leakage determination can be performed as part of test process or during normal memory operations.

Nonvolatile memory device and program method thereof
09741438 · 2017-08-22 · ·

A nonvolatile memory device includes at least two strings that are vertically stacked on a substrate and share one bit line. A program method of the nonvolatile memory device includes setting a pre-charge condition on the basis of a disturb environment between the at least two cell strings, pre-charging or not pre-charging an unselected cell string among the at least two cell strings in response to the pre-charge condition and programming memory cells in a selected cell string among the at least two cell strings.

Three dimensional stacked nonvolatile semiconductor memory in which the channel potential of a memory cell in a non-selected NAND cell unit is increased
11430521 · 2022-08-30 · ·

A three dimensional stacked nonvolatile semiconductor memory according to an example of the present invention includes a memory cell array comprised of first and second blocks. The first block has a first cell unit which includes a memory cell to be programmed and a second cell unit which does not include a memory cell to be programmed, and programming is executed by applying a program potential or a transfer potential to word lines in the first block after the initial potential of channels of the memory cells in the first and second cell units is set to a plus potential. In the programming, the program potential and the transfer potential are not applied to word lines in the second block.

Capacitance coupling parameter estimation in flash memories

A method for capacitance coupling parameter estimation includes determining a plurality of mean voltages among a plurality of memory cells of the memory in each of a plurality of cases related to inter-cell interference, generating a plurality of middle state mean voltages in response to the mean voltages, and adjusting one or more threshold voltages used to read from the memory based on the middle state mean voltages to operate independently of knowledge of middle state distributions in the memory cells.

Determining a read voltage based on a change in a read window

A change in a read window of a group of memory cells of a memory device that has undergone a plurality of program/erase cycles (PECs) can be determined. read voltage can be determined based at least in part on the determined change in the read window.

Memory system including a memory device, and methods of operating the memory system and the memory device

A method is provided for operating a memory device. The method includes counting, from among memory cells, a number of first off-cells with respect to a first reading voltage and a number of second off-cells with respect to a second reading voltage, comparing the number of first off-cells and the number of second off-cells, and determining, based on a result of the comparing, whether a programming error exists in a storage region in which the memory cells are included.

Reduced silicon-oxide-nitride-oxide-silicon (SONOS) flash memory program disturb

A method and apparatus for balancing voltage stress at a silicon-oxide-nitride-oxide-silicon (SONOS) flash memory array is disclosed. A particular cell of the SONOS flash memory array is selected for programming. A first voltage stress associated with a first SONOS transistor is determined if the particular cell is programmed. The first SONOS transistor is included in a first unselected cell of the SONOS flash memory array. A second voltage stress associated with a second SONOS transistor is determined if the particular cell is programmed. The first voltage stress and the second voltage stress are balanced prior to programming the particular cell.