ONO charging at different stages of microFlash/sup /spl reg// process flow

Abstract

In-process ultraviolet (UV) stimulated charging of ONO (oxide-nitride-oxide) stack is observed in fieldless microFlash (NROM) memory arrays. This problem is solved by introducing a UV blocking layer into the D1 dielectric. In this paper we discuss an alternative approach to the solution of charging problem. A micropartitioning technique is described that allows to screen out the operations responsible for ONO charging and corresponding equipment.