Hot carrier-induced aging of short channel SIMOX devices

Abstract

Degradation of submicron MOSFETs by hot carrier injection is addressed. Results illustrating the sensitivity of the front and bank interfaces to various hot-carrier injection conditions are presented. The influence of gate, substrate, and drain biases, duration, and channel length is evaluated. The devices were LOCOS isolated, N-channel LDD, and conventional P-channel MOSFETs with 1- mu m length. The localization of interface defects near the drain was studied. It is found that, in general, front channel transistors are very tolerant to aging. Once the LDD spacer was optimized, the degradation subsequent to 150 h of stress was almost insignificant. No degradation of the back interface occurred after stressing the front channel. Results obtained by stressing the back channel transistor are discussed. The back channel transconductance behavior is described.<>