Abstract: Technology for reading memory cells in three-dimensional memory having multiple tiers. The memory system erases the tiers within each block independently. Then, memory cells in the tiers are programmed by units such as word lines. The memory system determines one or more read parameters for the selected tier based on the programmed/erased states of the other tiers in the block. For example, the memory system may select read reference levels for the selected tier based on the programmed/erased states of the other tiers. In an aspect, the one or more read parameters are used to determine the set of reference voltages for a bit error rate estimation scan (BES).

Abstract: Techniques are presented that allow for the erase of the drain side select gates of NAND strings while maintaining the data content of the memory cells. While erase inhibiting the memory cells of a NAND string, holes are generated in the drain region through the gate induced drain leakage (GIDL) mechanism and transferred to under the select gate, where they are then used to erase the select gate by Fowler-Nordheim mechanism. This allows for the refresh of the drain side select gates while retaining the data content of the NAND strings. This technique can also be used for data encryption, since, by erasing the drain side select gates, a block of data can be rendered unreadable; but, since the data content is not erased, it can later be recovered.

Abstract: Embodiments of the disclosed technology relate to the operation of memory devices, and more particularly to sub-block mode (SBM) pre-charge operation sequences. One example embodiment provides a novel logic design of the control circuitry of a memory device using comments/instructions for the control circuitry. By virtue of the features of the disclosed technology, the control circuitry can effect pre-charging of an inner or middle vertical sub-block of a NAND string in a memory array. In some examples the NAND string has at least three vertical sub-blocks of non-volatile memory cells.

Abstract: A three tier memory has an upper sub block, a lower sub block, and a middle sub block. In the present disclosure, rather than precharging the upper and lower sub blocks, use is made of the middle sub block using a firmware (FW) scheme. Upon receiving a write request from a host, the FW will route the data to the middle sub block (SB1) through reverse order programming (ROP) so that the SB1 is pre-charged through the source side through the lower sub block (SB0). Once the SB1 is written, data is then routed to the SBO and then to the upper sub block (SB2). When there is a garbage collection (GC) request, the FW will move the data from the SB2 and then erase the SB2. Then the data moves from the SBO and SBO is erased. Finally, the data moves from the SB1 and then SB1 is erased.

Abstract: An apparatus includes control circuits configured to connect to a plurality of non-volatile memory cells. Each non-volatile memory cell is configured to store a plurality of bits of a plurality of logical pages including at least a first bit of a first logical page, a second bit of a second logical page and a third bit of a third logical page. The control circuits are configured to select a subset of the plurality of logical pages for reading, perform pre-read steps, and read a first and at least a second selected logical page of the subset without performing pre-read steps between reading the first and second selected logical pages.

Abstract: An apparatus includes control circuits configured to connect to a plurality of non-volatile memory cells. Each non-volatile memory cell is configured to store a plurality of bits of a plurality of logical pages including at least a first bit of a first logical page, a second bit of a second logical page and a third bit of a third logical page. The control circuits are configured to select a subset of the plurality of logical pages for reading, perform pre-read steps, and read a first and at least a second selected logical page of the subset without performing pre-read steps between reading the first and second selected logical pages.

Abstract: Apparatuses, systems, methods, and computer program products for enhanced erase retry of a non-volatile storage device are disclosed. An apparatus includes a non-volatile storage device and a controller. A controller includes a verification component configured to detect that an erase operation performed on an erase block of a non-volatile storage device is unsuccessful. A controller includes a parameter component configured to adjust one or more erase parameters for an erase operation. One or more erase parameters may be associated with one or more select gate drain storage cells of an erase block. A controller includes an erase component configured to retry an erase operation on an erase block with one or more adjusted erase parameters.

Abstract: Apparatuses, systems, and methods are disclosed for read threshold adjustment using reference data for non-volatile memory. An apparatus may include an array of non-volatile memory cells and a controller. A controller may be configured to write a predetermined reference data pattern to a region of an array. A controller may be configured to read reference data from a region. A controller may be configured to set one or more read thresholds based on identifying differences between reference data and a predetermined reference data pattern.

Abstract: Apparatuses, systems, and methods are disclosed for read threshold adjustment using reference data for non-volatile memory. An apparatus may include an array of non-volatile memory cells and a controller. A controller may be configured to write a predetermined reference data pattern to a region of an array. A controller may be configured to read reference data from a region. A controller may be configured to set one or more read thresholds based on identifying differences between reference data and a predetermined reference data pattern.

Abstract: Apparatuses, systems, methods, and computer program products for enhanced erase retry of a non-volatile storage device are disclosed. An apparatus includes a non-volatile storage device and a controller. A controller includes a verification component configured to detect that an erase operation performed on an erase block of a non-volatile storage device is unsuccessful. A controller includes a parameter component configured to adjust one or more erase parameters for an erase operation. One or more erase parameters may be associated with one or more select gate drain storage cells of an erase block. A controller includes an erase component configured to retry an erase operation on an erase block with one or more adjusted erase parameters.