Abstract: In a multi-tiered non-volatile memory structure that can perform operations on sub-blocks, performance of the different tiers/sub-blocks is made consistent by using different word line to word line pitches in the different tiers/sub-blocks.

Abstract: Technology is disclosed herein for a storage system that mitigates erase saturation when erasing memory cells. If erase does not pass after a number of erase loops, the storage system applies a program pulse to memory cells on faster to erase NAND strings. However, memory cells on slower to erase NAND strings are inhibited from programming. The program pulse increases the Vt of memory cells on the faster to erase NAND strings. Then, another erase loop is performed. The process may continue with additional loops, with each loop programming the memory cells on the faster to erase NAND strings followed by an erase pulse to all NAND strings and erase verify. Over-erase of the memory cells on the faster to erase NAND strings is therefore prevented. Moreover, slower to erase NAND strings that may otherwise be a bottleneck do not prevent successful completion of the erase.

Abstract: To increase performance, a non-volatile storage apparatus reduces the amount of time needed for program verify by eliminating a pause in the raising of word line voltages that has been used to allow the channels of memory cells to discharge. To compensate for the removal of the time previously used to allow the channels of memory cells to discharge without experiencing a disturb, a source line that is in communication with the channels is lowered from a source voltage applied to support programming to a source voltage applied to support sensing (for program verify) earlier than in previous designs such that the source line reaches the source voltage applied to support sensing (for program verify) prior to applying the verify reference voltage to the selected word line for program verify.

Abstract: A method for programming a memory array of a non-volatile memory structure, the memory comprising a population of MLC NAND-type memory cells, wherein the method comprises applying: (1) an inhibit condition to one or more bit lines of the memory array, and (2) a zero voltage condition to one or more bit lines of the memory array such that less than half of the adjacent bit lines of the memory array experience a voltage swing between the inhibit condition and the zero voltage condition.

Abstract: The memory device includes a memory block with a plurality of memory cells that are arranged in a plurality of word lines and in a plurality of channels. The memory device also includes circuitry that is configured to conduct a hole pre-charge operation to inject holes into the plurality of channels. The hole pre-charge operation includes applying a first voltage to the plurality of word lines to make the plurality of memory cells conductive to holes and applying a voltage to the channels from one side of the memory block to inject holes into the channels.

Abstract: A non-volatile memory system limits the amount of programming for a first type of group of non-volatile memory cells based on a first parameter such that a maximum number of programming pulses applied to the first type of group of non-volatile memory cells to program to the last data state after the first type of group of non-volatile memory cells completed programming to the other data states is X programming pulses. The non-volatile memory system limits the amount of programming for a second type of group of the non-volatile memory cells based on a second parameter such that a maximum number of programming pulses applied to the second type of group of non-volatile memory cells to program to the last data state after the second type of group of non-volatile memory cells completed programming to the other data states is Y programming pulses.

Abstract: A method for programming a memory array of a non-volatile memory structure, wherein the memory array comprises a population of MLC NAND-type memory cells, and the method comprises: (1) in a first program pulse, programming selected memory cells according to a first programmable state and a second programmable state, and (2) in a second program pulse, programming the selected memory cells according to a third programmable state.

Abstract: Non-volatile memory cells are programmed by pre-charging channels of unselected non-volatile memory cells connected to a selected data word line, boosting the channels of unselected non-volatile memory cells connected to the selected data word line after the pre-charging and applying a program voltage pulse to selected non-volatile memory cells connected to the selected data word line while boosting. The pre-charging includes applying pre-charge voltages to one set of data word lines and dummy word line(s) as well as applying overdrive voltages to another set of data word lines connected to already programmed memory cells. At the end of the pre-charging, the dummy word lines are ramped down to a resting voltage prior to lowering the data word lines to one or more resting voltages.

Abstract: In NAND memory, data sanitization allows a relatively small unit of data (e.g., less than a block) to be effectively destroyed by increasing threshold voltages of memory cells from their programmed threshold voltage to the highest threshold state. To reduce the amount of disturb on memory cells not selected for data sanitization, prior to applying a program voltage to a target word line, a hole based pre-charge operation is performed. More specifically, for NAND strings having a memory cell selected for data sanitation, prior to applying a programming pulse to the corresponding word line, a soft erase operation is performed. After biasing the memory cells and select gates of the NAND strings to a low voltage, a soft erase voltage pulse is applied to the source lines and bit line to pre-charge the NAND string channels with holes.

Abstract: To remedy short term data retention issues, a system creates a gate to channel voltage differential for non-volatile memory cells between programming and verifying in order to accelerate the effects of the short term data retention issue. That is, the gate to channel voltage differential will accelerate the migrating of electrons out of shallow traps. In some embodiments, the gate to channel voltage differential comprises a higher voltage at the channel in comparison to the gate. In some embodiments, the programming comprises applying doses of a programming signal and the gate to channel voltage differential is only created for a subset of the time periods between doses of the programming signal.

Abstract: The present disclosure is related to a programming technique for a memory device that includes a plurality of memory cells arranged in a plurality of word lines. An operating temperature of the memory device is determined. A spike pre-charge voltage is selected based on the operating temperature of the memory device. A first word line and a second word line are programmed in a first programming pass of a multi-pass programming operation. After the first programming pass is completed on the first and second word lines, the first word line is further programmed in a second programming pass that includes a plurality of program loops with pre-charge operations. The spike pre-charge voltage is applied to the second word line during each pre-charge operation.

Abstract: The memory device includes a memory block with memory cells arranged in word lines that are divided into sub-blocks. Control circuitry is configured to program each of the word lines of a selected sub-blocks in a plurality of program loops. During at least one program loop, the control circuitry applies a programming pulse to a selected word line. The control circuitry is also configured to simultaneously apply a verify voltage to the selected word line and a pass voltage to unselected word lines. In a first phase of a multi-phase pre-charge process, the control circuitry reduces the voltages applied to the selected word line and at least one unprogrammed word line to a low voltage. In a second phase that follows the first phase, the control circuitry reduces the voltages applied to all word lines that remained at the pass voltage to the low voltage.

Abstract: A non-volatile memory system programs memory cells from an erased threshold voltage distribution to programmed threshold voltage distributions by performing hole pre-charging of channels of unselected NAND strings in a selected block of a selected plane including applying a source voltage to a selected signal line of a plurality of signal lines that are isolated from each other. The selected signal line is positioned between the selected block and an unselected block and is connected to a selected source line of a plurality of source lines that are isolated from each other. The selected source line is connected to the selected block. The source voltage is greater in magnitude than any predetermined threshold voltage of the erased threshold voltage distribution. After the pre-charging, the system boosts channels of unselected NAND strings in the selected block and applies a program voltage to selected NAND strings in the selected block.

Abstract: Technology is disclosed herein for a memory system that includes one or more control circuits configured to connect to a three-dimensional memory structure that includes word lines, with each word line connected to a word line driver at one end. The one or more control circuits are configured to, in a program verify operation, sense memory cells of a first region of a selected word line for a first sense time and sense memory cells of a second region of the selected word line for a second sense time while applying a program-verify voltage to the selected word line. The first region is closer to the word line driver than the second region.

Abstract: A storage device is disclosed herein. The storage device comprises a non-volatile memory, where the non-volatile memory includes a block of 3N wordlines partitioned into a plurality of sub-blocks. The plurality of sub-blocks include an upper sub-block of a first subset of the block of 3N wordlines, a lower sub-block of a second subset of the block of 3N wordlines, and a middle sub-block of a third subset of the block of 3N wordlines. Further, the storage device comprises control circuitry coupled to the block of 3N wordlines and configured to: perform a program operation in a normal order programming sequence on the upper sub-block; perform a program operation in a reverse order programming sequence on the lower sub-block; and perform a program operation in the reverse order programming sequence on the middle sub-block.

Abstract: Technology is disclosed herein for a memory system that includes control circuits that are configured to connect to a three-dimensional memory structure. The memory structure includes NAND strings arranged in a plurality of rows, a plurality of bit lines connected to the NAND strings and a plurality of word lines, each word line coupled to the plurality of rows of NAND strings. The control circuits are configured to, in a program-verify operation, sense memory cells of a first row of NAND strings coupled to the selected word line for a first sense time and sense memory cells of a second row of NAND strings coupled to the selected word line for a second sense time while applying a program-verify voltage to the selected word line.

Abstract: A non-volatile memory includes a plurality of non-volatile memory cells arranged in blocks. Each block includes multiple sub-blocks that can be independently erased and programmed. A control circuit is connected to the non-volatile memory cells. The control circuit is configured to independently erase and program sub-blocks of a same block. The control circuit is configured to only allow one sub-block per block to be open at a time.

Abstract: Memory cells of a second sub-block are programmed by pre-charging channels of unselected memory cells connected to the selected word line, boosting the pre-charged channels of unselected memory cells and applying a program voltage to selected non-volatile memory cells connected to the selected word line. The pre-charging includes applying one or more overdrive voltages to word lines connected to memory cells of a first sub-block to provide a conductive path from memory cells of the second sub-block through the first sub-block to a source line and maintaining the word lines connected to memory cells of the first sub-block at one or more overdrive voltages while ramping down signals at the end of the pre-charging. Dummy word lines, positioned between sub-blocks, are maintained at a resting voltage during the boosting in order to cut-off channels of memory cells in the second sub-block from channels of memory cells in the first sub-block.

Abstract: The memory device includes a memory block with a plurality of memory cells, which are programmed to multiple bits per memory cell, arranged in a plurality of word lines. Control circuitry is provided and is configured to read the memory cells of a selected word line. The control circuitry separates the memory cells of the selected word line into a first group of memory cells, which are located on a side of the word line are near a voltage driver, and a second group of memory cells, which are located on an opposite side of the word line from the voltage driver. The control circuitry reads the memory cells of the first group using a first read mode and reads the memory cells of the second group using a second read mode that is different than the first read mode to reduce a fail bit count during read.

Abstract: In a non-volatile memory system that performs programming of selected memory cells (in coordination with pre-charging and boosting of channels for unselected memory cells) and program-verify to determine whether the programming was successful, the system transitions from program-verify to the next dose of programming by concurrently lowering a voltage applied to a selected word line and voltages applied to word lines on a first side of the selected word line at the conclusion of program-verify. Subsequent to lowering the voltage applied to the selected word line, the system successively lowers voltages applied to groups of one or more word lines on a second side of the selected word line at the conclusion of program-verify beginning with a group of one or more word lines immediately adjacent the selected word line and progressing to other groups of one or more word lines disposed increasingly remote from the selected word line.