Abstract: In a non-volatile memory, to achieve a shallow and tight erased threshold voltage distribution, a process is performed that includes erasing a group of non-volatile memory cells, identifying a first set of the bit lines that are connected to non-volatile memory cells of the group that are erased past a lower limit for erased non-volatile memory cells and identifying a second set of the bit lines that are connected to non-volatile memory cells of the group that are not erased past the lower limit for erased non-volatile memory cells, and applying programming to non-volatile memory cells connected to the first set of bit lines while inhibiting programming for non-volatile memory cells connected to the second set of bit lines.

Abstract: A memory device that uses different programming parameters base on the word line(s) to be programmed is described. The programming parameter PROGSRC_PCH provides a pre-charge voltage to physical word lines. In some instances, the PROGSRC_PCH voltage is decoupled, and a new PROGSRC_PCH represents an adjusted (e.g., increased) pre-charge voltage for a certain physical word line or word line zone (i.e., predetermined group of word lines). Using different PROGSRC_PCH voltages can limit or prevent Vt distribution window degradation, particularly for relatively low physical word lines. Additionally, the overall programming time and average current consumed can also be reduced.

Abstract: The memory device includes a plurality of memory cells, which include a first set of memory cells and a second set of memory cells. A controller is in communication with the memory cells. The controller is configured to, in a first programming pass and then a second programming pass, program the memory cells of the first and second sets to respective final threshold voltages associated with a plurality of programmed data states. The controller is further configured to, in the first programming pass, verify the first set of memory cells at a first set of checkpoint data states and verify the second set of memory cells at a second set of checkpoint data states that is different than the first set of checkpoint data states.

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: A memory system programs memory cells connected to a selected word line by applying doses of programming and performing program-verify between doses. An efficient and low current program-verify operation includes: while scanning the results of a previous program-verify operation, ramp up voltages on the select lines for the next program-verify operation without waiting for the scan to complete and ramp up voltages on unselected word lines for the next program-verify operation following a step signal (so that voltage applied to the unselected word lines rise in steps) without waiting for the scan to complete.

Abstract: Technology is disclosed herein for detecting grown bad blocks in a non-volatile storage system. A stress test may accelerate stressful conditions on the memory cells and thereby provide for early detection of grown bad blocks. The stress test may include applying a program voltage to a selected word line and a stress voltage that is less than a nominal boosting voltage to a word line adjacent one side of the selected word line. The combination of the program voltage and the stress voltage may generate an e-field that is stronger than an e-field that would be generated in a normal program operation, thereby accelerating the stress on the memory cells. The stress test mat further include programming all of the memory cells to a relatively high threshold voltage, which may create additional stress on the memory cells.

Abstract: Technology is disclosed herein in which a duration of a program pulse used to program non-volatile memory cells such as NAND may be increased responsive to a programming failure using a shorter duration program pulse. The duration of at least one program pulse may be increased for at least one group of memory cells in response to a failure to program a group using a default program pulse duration. The group that experiences the increased duration program pulse may be the same group for which the program operation failed using the shorter program pulse or may be a different group than the group for which the program operation failed using the shorter program pulse.

Abstract: Technology is disclosed herein for a memory system that balances peak Icc with programming speed. A memory system applies voltages to respective word lines during a verify operation that balances peak Icc with programming speed. The voltages for which the ramp rate is controlled include a read pass voltage applied to unselected word lines and a spike voltage applied to the selected word line at the beginning of the verify. The ramp rate of the voltages is slow enough to keep the peak Icc during verify to a target peak Icc regardless of which word line is selected for verify. However, the ramp rate of the voltages to the word lines during verify is fast enough to make use of the target peak Icc in order achieve faster programming. Therefore, the impact on programming time is minimized while staying within the allowed peak Icc.

Abstract: Technology is disclosed herein for a memory system that compensates for different programming speeds in two sets of memory cells when reading those two sets of memory cells. The memory system programs a group of the memory cells to one or more data states. In one aspect, the memory cells are not verified during programming. The group has a first set of memory cells that program at a first speed and a second set of memory cells that program at a second speed. The memory system reads the first set of the memory cells with a first set of read parameters and reads the second set of the memory cells with a second set of read parameters. The first set of read parameters are different from the second set of read parameters to compensate for the different programming speeds.

Abstract: A memory device includes a horizontal source layer which is laterally separated into laterally isolated portions located in adjacent memory blocks by a dielectric backside trench fill structure or a source isolation dielectric structure.

Abstract: A memory device includes a horizontal source layer which is laterally separated into laterally isolated portions located in adjacent memory blocks by a dielectric backside trench fill structure or a source isolation dielectric structure.

Abstract: In order to lower the peak and average current through the channel (thereby lowering peak and average power consumption) during program-verify, which exhibits a word line dependency, the inventors propose to program dummy memory cells connected to a dummy word line before programming data memory cells connected to a data word line. The additional resistance in the NAND string introduced by the preprogrammed dummy memory cells will cause the peak current, and power consumption, to be lower. To address the word line dependency, the dummy memory cells connected to the dummy word line can be programmed to different threshold voltages based on which data word line is to be programmed. Thus, prior to programming data non-volatile memory cells connected to a particular data word line, the dummy memory cells are programmed to a threshold voltage that is chosen based on the position of the particular data word line.

Abstract: To reduce data disturbs and lower current requirements of a 3D NAND memory die, a multi-block plane of non-volatile memory cells has its source line separated into multiple source line regions by introduction of isolation trenches. The plane structure for the NAND memory is maintained, but is broken into multi-block sub-planes, each with an independently biasable source line.

Abstract: An apparatus includes a control circuit configured to connect to memory cells connected in series in NAND strings. Each NAND string includes a plurality of data memory cells coupled to a plurality of data word lines in series with a plurality of dummy memory cells connected to a plurality of dummy word lines. The control circuit configured to apply a first dummy word line voltage to one or more dummy word lines of the plurality of dummy word lines in a verify step of a program operation to program data memory cells. The control circuit is configured to apply a second dummy word line voltage to the one or more dummy word lines in a read operation to read the data memory cells.

Abstract: An apparatus includes a control circuit configured to connect to NAND strings that are connected to bit lines, where each bit line is connected to a plurality of NAND strings in a corresponding plurality of regions of a block. The control circuit is configured to apply a read voltage in read operations directed to NAND strings of the plurality of regions of the block and subsequently adjust the read voltage by a first predetermined amount for read operations directed to NAND strings of a first region of the block. The control circuit is further configured to adjust the read voltage by a second predetermined amount for read operations directed to NAND strings of a second region of the block. The first and second predetermined amounts are based on respective locations of the first and second regions in the block.

Abstract: To reduce spikes in the current used by a NAND memory die, different ramp rates are used for the pass voltage applied to unselected word lines during a program operation depending on whether data is stored in a multi-level cell (MLC) format or in a single level cell (SLC) format. These ramp rates can be determined through device characterization and stored as parameter values on the memory die. Different ramp rate interval values can also be used for the pass voltage applied to unselected word lines during a program operation depending on whether data is stored in an MLC format or in an SLC format.

Abstract: To reduce spikes in the current used by a NAND memory die, different ramp rates for different regions, or zones, of word lines are used for the pass voltage applied to unselected word lines during a program operation. The properties of the word lines, such as their resistance and capacitance (RC) values, vary across the NAND memory array. By determining the RC values of the word lines across the array, the word lines can be broken into multiple zones based on these properties. The zones can then be individually assigned different ramp rates for applying a pass voltage to the unselected word lines, where a parameter for the ramp rates can be stored as a register value on the memory die.

Abstract: Technology is disclosed herein for detecting grown bad blocks in a non-volatile storage system. A stress test may accelerate stressful conditions on the memory cells and thereby provide for early detection of grown bad blocks. The stress test may include applying a program voltage to a selected word line and a stress voltage that is less than a nominal boosting voltage to a word line adjacent one side of the selected word line. The combination of the program voltage and the stress voltage may generate an e-field that is stronger than an e-field that would be generated in a normal program operation, thereby accelerating the stress on the memory cells. The stress test mat further include programming all of the memory cells to a relatively high threshold voltage, which may create additional stress on the memory cells.

Abstract: In a non-volatile memory, to achieve a shallow and tight erased threshold voltage distribution, a process is performed that includes erasing a group of non-volatile memory cells, identifying a first set of the bit lines that are connected to non-volatile memory cells of the group that are erased past a lower limit for erased non-volatile memory cells and identifying a second set of the bit lines that are connected to non-volatile memory cells of the group that are not erased past the lower limit for erased non-volatile memory cells, and applying programming to non-volatile memory cells connected to the first set of bit lines while inhibiting programming for non-volatile memory cells connected to the second set of bit lines.

Abstract: A system has been described that performs differential temperature compensation based on a differential between the temperature at time of programming and temperature at time of reading for a set of data. Differential temperature compensation is useful for bulk programming/reading (e.g., many pages of data) and/or programming/reading super pages of data (multiple pages residing on different memory die).