Sandisk Technologies Inc.

Shubhajit Mukherjee

Xiang Yang

Abhijith Prakash

Deepanshu Dutta

Jiacen Guo

Gerrit Jan Hemink

The techniques include a memory device receiving a data write instruction. The memory device programs the memory cells of the memory blocks to a one bit per memory cell (SLC) format with a first and second SLC data states. In response to the data programmed to the memory cells of the memory blocks reaching an SLC limit prior to completion of the data write instruction, without erasing the memory cells, the memory device programs at least some of the memory cells from the SLC format to a two bits per memory cell (MLC) format. When programming from the SLC format to the MLC format, the memory device inhibits programming of some of the memory cells in the first and second SLC data states to form a first MLC data state and programs other memory cells of the SLC data states to form second, third, and fourth MLC data states.

In-place write techniques without erase in a memory device

A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to word lines including at least one edge word line and other data word lines. The memory cells are arranged in strings and are configured to retain a threshold voltage corresponding to data states. The strings are organized in rows and a control means is coupled to the word lines and the strings and identifies the at least one edge word line. The control means programs the memory cells of the strings in particular ones of the rows and associated with the at least one edge word line to have an altered distribution of the threshold voltage for one or more of the data states compared to the memory cells of the strings not in particular ones of the rows and not associated with the at least one edge word line during a program operation.

Edge word line data retention improvement for memory apparatus with on-pitch semi-circle drain side select gate technology

A memory apparatus and method of operation are provided. The memory apparatus includes memory cells configured to retain a threshold voltage. The memory cells are connected to one of a plurality of word lines and are arranged in strings comprising a plurality of blocks. A control means is coupled to the plurality of word lines and the strings and is configured to periodically determine a read frequency metric associated with a plurality of read operations of one of the plurality of blocks of the memory cells. The control means is also configured to relocate data of the one of the plurality of blocks and cause the one of the plurality of blocks to remain unused for a predetermined relaxation time based on the read frequency metric.

Method to fix cumulative read induced drain side select gate downshift in memory apparatus with on-pitch drain side select gate

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.

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San Jose, CA, United States of America

Shubhajit Mukherjee