A 3.3 V 128 Mb multi-level NAND flash memory for mass storage applications

Abstract

The NAND flash memory was originally designed to target solid-state mass storage applications. Key requirements of mass storage, low cost and high serial access throughput, have been achieved by sacrificing a non-critical feature, fast random access. For a quantum step in cost reduction, the multi-level cell is combined with NAND flash memory. This 128 Mb multi-level NAND flash memory stores two bits per cell by tight programmed cell threshold voltage (Vth) control and is made practical by significantly reducing program disturbs.