SanDisk, an innovator in the flash memory space, has recently announced improvements to both SSD and microSD cells which should significantly improve capacity.

Leading the show is the introduction of an X4 MLC NAND cell which permits the storage of up to four bits of data per cell. This is twice the areal density of the predominant X2 cell, and a 33% improvement to SanDisk’s X3 cell demonstrated at last year’s ISSCC event.

The firm reports that its I/O performance is similar to that of current SSDs. This claim is surprising as an increase in density often directly equates to a decrease in speed. If SanDisk has managed to eliminate this roadblock, then much of the victory can be attributed to the flash controller they developed specifically for the X4 cell.

Trailing the announcement of the 43nm flash cell, SanDisk also took the wraps off the world’s first 32nm microSD NAND flash cell. The smallest such cell to date, the 113mm^2 die will double the current maximum capacity to 32GB.

Regarding the new technologies, Memory Technology VP for SanDisk A Klaus Schuegraf discussed some of the technologies at play in the recent announcements. “32nm technology builds upon SanDisk’s … deployment of immersion lithography in 43nm to implement spacer process without incurring additional investment in capital-intensive lithography equipment. SanDisk brings its … 64-bit NAND string length to 32nm, while compensating for bit-to-bit interference effects with innovative programming algorithms and system design.”

All told, we can expect products based upon the new cells to start appearing in volume by the end of the year. It is believed that these new devices will yet again lower the cost per megabyte in the flash arena.