Abstract: A memory apparatus and method of operation are provided. The memory apparatus includes memory cells connected to one of a plurality of word lines including an edge word line and a plurality of other data word lines. The memory cells are disposed in memory holes organized in rows grouped in a plurality of strings. The rows include full circle rows and semi-circle rows. A control means is configured to program the memory cells connected to the edge word line and in the semi-circle rows of a first one and a second one of the plurality of strings to a predetermined one of a plurality of data states in a first program operation. The control means then selects both the first one and the second one of the plurality of strings together and programs the memory cells of the full circle rows together in a second program operation.

Abstract: A memory system identifies memory cells connected to a common word line that have had their threshold voltage unintentionally drift lower than programmed by determining whether memory cells meet two criteria: (1) the memory cells have threshold voltages within an offset of a read compare voltage of a data state; and (2) adjacent memory cells (connected to word lines that are adjacent to the common word line) are in one or more low data states. For those memory cells meeting the two criteria, the memory system performs some amount of programming on the memory cells to refresh the data stored in those memory cells to be as originally intended.

Abstract: Programming a plurality of non-volatile memory cells includes performing a soft erase process during the programming. The soft erase process includes pre-charging channels of the memory cells and performing an erase operation subsequent to the pre-charging while the channels are at one or more elevated voltages at least partially due to the pre-charging.

Abstract: A memory device with one or more planes having sub-blocks is disclosed. The memory device may further include a voltage switch transistor for each of sub-blocks. Additionally, the memory device may further include a row decoder for each of sub-blocks. As a result, an operation to two sub-blocks can be performed at different times. For example, using a row decoder and voltage switch transistor, a sub-block can be initially read, followed by a subsequent read of another sub-block using a separate row decoder and voltage switch transistor. By staggering the read operations through a time delay, the peak current Icc associated with the supply voltage can be reduced.

Abstract: An apparatus includes a control circuit configured to connect to first word lines of a first vertical sub-block and second word lines of a second vertical sub-block. The first vertical sub-block and the second vertical sub-block include memory cells connected in series in NAND strings, each NAND string including memory cells coupled to the first word lines in series with memory cells connected to the second word lines. The control circuit is configured to program or sense memory cells along a selected first word line of the first vertical sub-block while applying a first voltage to second word lines that are connected to programmed memory cells and applying a second voltage to second word lines that are connected to unprogrammed memory cells.

Abstract: Apparatuses and techniques are described for controlling a bit line pre-charge voltage in a program operation based on a number of bits per cell, with a goal to reduce peak current consumption. In one aspect, the ramp up of a bit line voltage to an inhibit level is optimized according to the number of bits per cell. The ramp up can involve increasing the bit line voltage from an initial level to a target voltage at a regulated rate, then increasing the bit line voltage from the target voltage to a final voltage at an unregulated rate. In one approach, the regulated ramp rate is less for single-level cell programming compared to multi-level cell programming. The target voltage can also be optimized based on the number of bis per cell.

Abstract: A memory device is provided in which blocks of memory cells are divided into separate portions or sub-blocks with respective sets of word line switching transistors. The sub-blocks can be arranged on a substrate on opposite sides of a dividing line, where a separate set of bit lines is provided on each side of the dividing line. Each block has a row decoder which provides a common word line voltage signal to each sub-block of the block. However, each sub-block can have an independent set of word line switching transistors so that the common word line voltage signal can be passed or blocked independently for each sub-block. The blocks of memory cells can be provided on a first die which is inverted and bonded to a second die which includes the sets of word line switching transistors.

Abstract: A memory apparatus and method of operation are provided. The apparatus includes apparatus including memory cells connected to word lines including at least one dummy word line and data word lines. The memory cells are arranged in strings and are configured to retain a threshold voltage. The apparatus also includes a control means coupled to the word lines and the strings and configured to identify ones of the memory cells connected to the at least one dummy word line with the threshold voltage being below a predetermined detection voltage threshold following an erase operation. The control means is also configured to selectively apply at least one programming pulse of a maintenance program voltage to the at least one dummy word line to program the ones of the memory cells connected to the at least one dummy word line having the threshold voltage being below the predetermined detection voltage threshold.

Abstract: A memory apparatus and method of operation is provided. The apparatus includes a block of memory cells. Each of the memory cells is connected to one of a plurality of word lines and are also arranged in strings and configured to retain a threshold voltage within a common range of threshold voltages. A control circuit coupled to the plurality of word lines and the strings is configured to determine an erase upper tail voltage of a distribution of the threshold voltage of the memory cells following an erase operation. The erase upper tail voltage corresponds to a cycling condition of the memory cells. The control circuit is also configured to calculate a program voltage to apply to each of selected ones of the plurality of word lines associated with the memory cells to program the memory cells during a program operation based on the erase upper tail voltage.

Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells connected to word lines and bit lines and arranged in strings and configured to retain a threshold voltage. Each of the memory cells is configured to be erased in an erase operation occurring during an erase time period. A control circuit is configured to adjust at least a portion of the erase time period in response to determining the erase operation is a segmented erase operation and is resumed after being suspended. The control circuit applies an erase signal having a plurality of voltage segments temporally separated from one another during the erase time period to each of the strings while simultaneously applying a word line erase voltage to selected ones of the word lines to encourage erasing of the memory cells coupled to the selected ones of the word lines in the segmented erase operation.

Abstract: In a non-volatile memory, a block of NAND strings is divided into sub-blocks by etching the select gate layers between sub-blocks. This results in a subset of NAND strings (e.g., at the border of the sub-blocks) having select gates that are partially etched such that the partially etched select gates are partially shaped as compared to the select gates of NAND strings that have not been etched. Host data is programmed to non-volatile memory cells that are connected to an edge word line and are on NAND strings having a complete shaped select gate. Host data is also programmed to non-volatile memory cells that are connected to non-edge word lines. However, host data is not programmed to non-volatile memory cells that are connected to the edge word line and are on NAND strings having a partial shaped select gate.

Abstract: A storage device is provided that conditionally performs read refresh in blocks having higher P/E cycles or older programming times, while refraining from performing read refreshes in blocks having lower P/E cycles or recent programming times. The storage device includes a memory and a controller. The memory includes a block having cells. The controller performs a read refresh on the cells when a number of P/E cycles of the block exceeds an age threshold or after a threshold amount time has elapsed since data was programmed in the block. The controller may also refrain from performing read refreshes on the cells until the number of P/E cycles exceeds the age threshold or until a threshold amount of time has elapsed since the data is programmed. As a result, lower BER may occur due to wider Vt margins, while power and system overhead may be saved.

Abstract: A memory device is provided in which blocks of memory cells are divided into separate portions or sub-blocks with respective sets of word line switching transistors. The sub-blocks can be arranged on a substrate on opposite sides of a dividing line, where a separate set of bit lines is provided on each side of the dividing line. Each block has a row decoder which provides a common word line voltage signal to each sub-block of the block. However, each sub-block can have an independent set of word line switching transistors so that the common word line voltage signal can be passed or blocked independently for each sub-block. The blocks of memory cells can be provided on a first die which is inverted and bonded to a second die which includes the sets of word line switching transistors.

Abstract: A storage device is provided that applies pulsed biasing during power-up or read recovery. The storage device includes a memory and a controller. The memory includes a block having a word line and cells coupled to the word line. The controller applies a voltage pulse to the word line during power-up or in response to a read error. The voltage pulse may include an amplitude and a pulse width that are each a function of a number of PIE cycles of the block. The controller may also perform pulsed biasing during both power-up and read recovery by applying one or more first voltage pulses to the word line during power-up and one or more second voltage pulses to the word line in response to a read error. As a result, lower bit error rates due to wider Vt margins may occur and system power may be saved over constant biasing.

Abstract: A storage device is provided that performs constant biasing in priority blocks, such as OTP memory blocks (fuse ROM) and flash memory blocks having a threshold number of P/E cycles. The storage device includes an OTP memory, a flash memory, and a controller. The OTP memory includes a block having a word line and a plurality of cells coupled to the word line. The flash memory includes another block having a word line and a plurality of cells coupled to this word line. The controller is configured to apply a constant bias to the word line of the OTP memory block and, in some cases to the word line of the flash memory block, between execution of host commands. As a result, lower bit error rates due to wider Vt margins may occur while system power may be saved through selective application of constant biasing.

Abstract: To improve programming performance for a non-volatile memory , the verification of multiple programming levels can be performed based on a single discharge of a sensing capacitor through a selected memory cell by using different voltage levels on a second plate of the sensing capacitor: after discharging a first plate of the sensing capacitor through the selected memory cell, a result amount of charge is trapped on the first plate, which is then used to set first and second control gate voltages on a sensing transistor whose control gate is connected to the first place of the sensing capacitor based on respectively setting the second plate of the sensing capacitor to first and second voltage levels. To further improve programming performance, when the non-volatile memory stores in a multistate format, after the next to highest data state finishes programming, the next programming pulse can use a larger step size.

Abstract: A method for programming a memory block of a non-volatile memory structure, wherein the method comprises, during a program verify operation, selecting only a partial segment of memory cells of a memory block for bit scan mode, applying a sensing bias voltage to one or more bit lines of the memory block associated with the selected memory cells, and initiating a bit scan mode of the selected memory cells.

Abstract: To improve programming performance for a non-volatile memory , the verification of multiple programming levels can be performed based on a single discharge of a sensing capacitor through a selected memory cell by using different voltage levels on a second plate of the sensing capacitor: after discharging a first plate of the sensing capacitor through the selected memory cell, a result amount of charge is trapped on the first plate, which is then used to set first and second control gate voltages on a sensing transistor whose control gate is connected to the first place of the sensing capacitor based on respectively setting the second plate of the sensing capacitor to first and second voltage levels. To further improve programming performance, when the non-volatile memory stores in a multistate format, after the next to highest data state finishes programming, the next programming pulse can use a larger step size.

Abstract: A method for detecting and isolating defective memory plane(s) of a non-volatile memory structure during a program verify operation, comprising: initiating, for each plane, a word line verify voltage level scan with a bit scan pass fail criterion and at a starting voltage located within an intended program threshold voltage distribution curve, incrementally decreasing the word line verify voltage by a predetermined offset until a specific condition of the scan is obtained, and storing the voltage at which the specific condition of the scan is obtained, wherein the stored voltage represents a voltage of an upper tail portion of an actual programmed threshold voltage distribution curve of the plane. The stored voltages of all of the memory planes of the structure are compared to determine which plane corresponds to the lowest stored voltage. A “fail” status is applied to the plane corresponding to the lowest stored voltage.

Abstract: Aspects of a storage device including a memory and a controller are provided. The memory can include memory dies that draw a current from a current source during a program operation. The controller may monitor for an alarm signal from the memory dies on a first common channel between the controller and the memory dies. The alarm signal indicates that a corresponding memory die is entering an operational state that draws a peak current from the current source for the program operation. The controller can receive, from the memory dies, one or more alarm signals on the first common channel within a predetermined threshold time. The controller can transmit a postpone signal on a second common channel to the memory dies based on the one or more alarm signals received within the predetermined threshold time.