Operation characterization of flash memory with silicon nitride/silicon dioxide stack tunnel dielectric

Abstract

The operating characteristics of flash memory devices with tunnel dielectrics comprising a silicon nitride layer or a silicon nitride/silicon dioxide (N/O) stack and annealed at various temperatures are studied. The present work indicates that flash memory devices with an N/O stack tunnel dielectric have a higher program/erase speed and reliability than those with a single Si3N4 layer. The stack tunnel dielectric composed of a thick Si3N4 layer and a thin SiO2 layer exhibits even better performance for flash memory operation. Flash memory devices having N/O stack tunnel dielectrics annealed at low temperatures show better performance in terms of erase speed and charge retention but poor robustness under read disturbance. © 2005 The Japan Society of Applied Physics.