Abstract: Techniques are presented to reduce the amount of read disturb on partially written blocks of NAND type non-volatile memory, both for when determining the last written word line in a block and also for data read. In both cases, non-selected word lines that are unwritten or, in the case of finding the last written word line, may be unwritten are biased with a lower read-pass voltage then is typically used. The result of such reads can also be applied to an algorithm for finding the last written word by skipping a varying number of word lines. Performance in a last written page determination can also be improved by use of shorter bit line settling times than for a standard read.

Abstract: Systems and methods for performing data recovery are disclosed. A controller of a memory system may detect an error at a first page of memory and identify a data keep cache associated with the first page, the data keep cache associated with a primary XOR sum. The controller may further sense data stored at a second page and move the data to a first latch of the memory; sense data stored at a third page such that the data is present in a second latch of the memory; and calculate a restoration XOR sum based on the data of the second page and the data of the third page. The controller may further calculate the data of the first page based on the primary XOR sum and the restoration XOR sum, and restore the data of the first page.

Abstract: A non-volatile storage system identifies a word line with an open neighbor word line and determines whether data stored in non-volatile memory cells connected to the identified word line has an error condition. If the data does have an error condition, then an attempt is made to fix the data and the open neighbor word line is checked for errors. If the open neighbor word line has errors, then memory cells connected to the open neighbor word line are programmed with pseudo data.

Abstract: An array of non-volatile memory cells includes a first plurality of nonvolatile memory cells and a second plurality of non-volatile memory cells. The first plurality of memory cells, which have first diameters of memory holes, are assigned to store portions of data that are not frequently read. The second plurality of memory cells, which have second diameters of memory holes, are assigned to store portions of data that are frequently read. The first diameters are smaller than the second diameters.

Abstract: Methods and systems are provided where non-volatile solid state memory may include selected memory cells coupled to a selected word line and proxy memory cells coupled to a proxy word line. The selected memory cells may be non-adjacent to the proxy memory cells and be selected for a read operation. A read proxy voltage may be applied to the proxy word line when data is read from the selected memory cells. A read disturb may be determined based on a difference between a predetermined value stored in the proxy memory cells and a value read from the proxy memory cells.

Abstract: A non-volatile memory system includes a plurality of NAND strings (or other arrangements) that form a monolithic three dimensional memory structure, bit lines, word lines, and one or more control circuits. Multiple NAND strings of the plurality of NAND strings have different select gates connected to different select lines. The multiple NAND strings are connected to a common bit line. The multiple NAND strings are connected to a common word line via their respective different select gates. The one or more control circuits concurrently program multiple memory cells on the multiple NAND strings.

Abstract: Methods and systems are provided where non-volatile solid state memory may include selected memory cells coupled to a selected word line and proxy memory cells coupled to a proxy word line. The selected memory cells may be non-adjacent to the proxy memory cells and be selected for a read operation. A read proxy voltage may be applied to the proxy word line when data is read from the selected memory cells. A read disturb may be determined based on a difference between a predetermined value stored in the proxy memory cells and a value read from the proxy memory cells.

Abstract: A non-volatile memory system includes a plurality of NAND strings (or other arrangements) that form a monolithic three dimensional memory structure, bit lines, word lines, and one or more control circuits. Multiple NAND strings of the plurality of NAND strings have different select gates connected to different select lines. The multiple NAND strings are connected to a common bit line. The multiple NAND strings are connected to a common word line via their respective different select gates. The one or more control circuits concurrently program multiple memory cells on the multiple NAND strings.

Abstract: A non-volatile flash memory has bit lines spanning multiple blocks grouped into columns, where each block is connected along multiple regular columns and one or more redundancy columns. When there is a local column defect, so that the defect is not at the level of the whole block or global column, the portions of a column at an individual block can be remapped to a portion of the same block along a redundant column. Sections of multiple columns from different blocks can be remapped to the same redundancy column. Then a memory block includes a number of independently accessible sub-blocks, the process can also be implemented at the sub-block level. A dynamic, system level implementation is presented.

Abstract: Methods and systems are provided where non-volatile solid state memory may include selected memory cells coupled to a selected word line and proxy memory cells coupled to a proxy word line. The selected memory cells may be non-adjacent to the proxy memory cells and be selected for a read operation. A read proxy voltage may be applied to the proxy word line when data is read from the selected memory cells. A read disturb may be determined based on a difference between a predetermined value stored in the proxy memory cells and a value read from the proxy memory cells.

Abstract: A non-volatile storage system identifies a word line with an open neighbor word line and determines whether data stored in non-volatile memory cells connected to the identified word line has an error condition. If the data does have an error condition, then an attempt is made to fix the data and the open neighbor word line is checked for errors. If the open neighbor word line has errors, then memory cells connected to the open neighbor word line are programmed with pseudo data.

Abstract: Methods and systems are provided where non-volatile solid state memory may include selected memory cells coupled to a selected word line and proxy memory cells coupled to a proxy word line. The selected memory cells may be non-adjacent to the proxy memory cells and be selected for a read operation. A read proxy voltage may be applied to the proxy word line when data is read from the selected memory cells. A read disturb may be determined based on a difference between a predetermined value stored in the proxy memory cells and a value read from the proxy memory cells.

Abstract: Systems, apparatuses, and methods may be provided that adapt to trim set advancement. Trim set advancement may be a change in trim sets over time. A cell of a semiconductor memory may have a first charge level and be programmed with a first trim set. The cell may be reprogrammed by raising the first charge level to a second charge level that corresponds to the cell programmed with a second trim set.

Abstract: A non-volatile flash memory has bit lines spanning multiple blocks grouped into columns, where each block is connected along multiple regular columns and one or more redundancy columns. When there is a local column defect, so that the defect is not at the level of the whole block or global column, the portions of a column at an individual block can be remapped to a portion of the same block along a redundant column. Sections of multiple columns from different blocks can be remapped to the same redundancy column. Then a memory block includes a number of independently accessible sub-blocks, the process can also be implemented at the sub-block level. A dynamic, system level implementation is presented.

Abstract: A method may be performed in a data storage device that includes a memory and a controller, in response to a request to read data from the memory. The data is located within a first word line of the memory. The method includes accessing the data from the first word line and determining, based on a probability threshold, whether to perform a remedial action with respect to a second word line.

Abstract: A number of complimentary techniques for the read scrub process using adaptive counter management are presented. In one set of techniques, in addition to maintaining a cumulative read counter for a block, a boundary word line counter can also be maintained to track the number of reads to most recently written word line or word lines of a partially written block. Another set of techniques used read count threshold values that vary with the number of program/erase cycles that a block has undergone. Further techniques involve setting the read count threshold for a closed (fully written) block based upon the number reads it experienced prior to being closed. These techniques can also be applied at a sub-block, zone level.

Abstract: Systems and methods for performing data recovery are disclosed. A controller of a memory system may detect an error at a first page of memory and identify a data keep cache associated with the first page, the data keep cache associated with a primary XOR sum. The controller may further sense data stored at a second page and move the data to a first latch of the memory; sense data stored at a third page such that the data is present in a second latch of the memory; and calculate a restoration XOR sum based on the data of the second page and the data of the third page. The controller may further calculate the data of the first page based on the primary XOR sum and the restoration XOR sum, and restore the data of the first page.

Abstract: In a block-erasable nonvolatile memory array, blocks are categorized as bad blocks, prime blocks, and sub-prime blocks. Sub-prime blocks are identified from their proximity to bad blocks or from testing. Sub-prime blocks are configured for limited operation (e.g. only storing non-critical data, or data copied elsewhere, or using some additional or enhanced redundancy scheme).

Abstract: Systems and methods for performing data recovery are disclosed. A controller of a memory system may detect an error at a first page of memory and identify a data keep cache associated with the first page, the data keep cache associated with a primary XOR sum. The controller may further sense data stored at a second page and move the data to a first latch of the memory; sense data stored at a third page such that the data is present in a second latch of the memory; and calculate a restoration XOR sum based on the data of the second page and the data of the third page. The controller may further calculate the data of the first page based on the primary XOR sum and the restoration XOR sum, and restore the data of the first page.

Abstract: Techniques are presented to reduce the amount of read disturb on partially written blocks of NAND type non-volatile memory, both for when determining the last written word line in a block and also for data read. In both cases, non-selected word lines that are unwritten or, in the case of finding the last written word line, may be unwritten are biased with a lower read-pass voltage then is typically used. The result of such reads can also be applied to an algorithm for finding the last written word by skipping a varying number of word lines. Performance in a last written page determination can also be improved by use of shorter bit line settling times than for a standard read.