High speed and nonvolatile Si nanocrystal memory for scaled flash technology using highly field-sensitive tunnel barrier

Abstract

For the first time, a nitride/oxide/nitride stacked tunnel structure is adopted as highly field-sensitive tunnel barrier to improve both program/erase speed and data retention of nanocrystal memory. Product-adaptive nonvolatility (>10 years at 85/spl deg/C) and cycling endurance (>10/sup 6/) were obtained with the program time of 10 /spl mu/s at V/sub G/=8 V and the erase time of 100 /spl mu/s at V/sub G/=-8 V with 0.84 V threshold window. The program speed was 100 times faster and the voltage was about 10 V smaller than those of a conventional NAND type flash memory cell. These results strongly suggest that nanocrystal floating gate memory becomes a promising solution to overcome the scaling limitation of the conventional floating gate memory cell.