Electron trap distribution in thin oxide after high-field stress

摘要

The centroid of neutral electron trap distribution in 80 A SiO_2 film after high-field electrical stress is determined using trap-filling measurements that can eliminate the contributions from trapped holes and interface trapped charges—complications that introduce ambiguity in previous studies. The centroid is found to be roughly half way between the midpoint of the oxide and the injecting electrode, implying an extremely nonuniform distribution. Such a highly nonuniform distribution is at odds with the assumption used in most oxide breakdown models. The impact of a highly nonuniform neutral trap distribution on thin oxide reliability projection could be important.