SanDisk and Toshiba Develop 128Gb MLC NAND Flash Chip

SanDisk Corporation has developed the world’s smallest 128Gb NAND flash memory chip currently in production.

The semiconductor device can store 128 billion individual bits of information on a single silicon die 170mm² in size – a little more than a quarter of an inch squared, or smaller than the area covered by a U.S. penny.

The use of NAND flash memory in high tech equipment like smartphones, tablets and SSDs allows advances in the full function, small form factor devices. Shrinking the size of NAND flash memory allows smaller, more powerful computing, communications and consumer electronics devices to be built while keeping costs low.

SanDisk built the 128Gb NAND flash memory chip on the company’s 19nm process technology. A nanometer measures one-billionth of a meter, meaning that 19nm circuit lines are so small that about 3,000 of them could fit across the width of a human hair. The chip also employs SanDisk’s three-bit per cell (X3) technology that allows the company to build NAND flash memory products with the ability to read and write three bits of information in each memory cell.

At 19nm, SanDisk is deploying its ninth generation of MLC NAND products and fifth generation of X3 technology. This combination of manufacturing and technical expertise helps SanDisk pack more information into each memory cell making it possible to create a smaller, denser NAND flash memory chip.

"Building a 128Gb NAND flash memory chip with this level of complexity is an incredible achievement," said Mehrdad Mofidi, vice president, Memory Design. "This innovation allows SanDisk to continue to be a leader in helping our customers deliver smaller, more powerful products capable of doing more at lower cost."

In addition to reduced size, the 128Gb semiconductor device has a 3 write performance of 18MB/s. This level of performance is achieved using patented all bit line (ABL) architecture and means that X3 technology could be extended to certain product categories that use MLC NAND flash memory.

The 128Gb NAND flash memory chip was developed jointly by teams from SanDisk and Toshiba at SanDisk’s Milpitas campus. The effort was led by Yan Li, director of Memory Design at SanDisk.

Products based on the 128Gb three-bit per cell technology began shipping late last year and have started to ramp into volume production.

SanDisk has also developed a derivative product based on the 128Gb chip – a 64Gb, X3 NAND flash memory chip that is compatible with the microSD format. The company has also started to ramp production of this additional chip technology.