Low-cost embedded Flash memory technology

Abstract

A simple and low cost logic based single poly Flash memory technology, NeoFlash®, with fast programming and high reliability is demonstrated in this paper. Programming with channel hot-hole-induced hot-electron injection and erasure with uniform channel Fowler-Nordheim tunneling are utilized to achieve fast programming, high endurance and good reliability characteristics. Owing to its simple cell structure and operation schemes, only 3 additional non-critical masks are needed, and the complexity of process integration and device tuning is much reduced. The SONOS based technology has been successfully embedded into 0.35μm ∼ 65nm CMOS logic process. Because of electrons stored in nitride layer of ONO film, no tail bit during endurance and retention test is observed. As a result, NeoFlash® is a promising embedded Flash technology for SoC applications.