Nonlocal hot-electron injection as the mechanism for the predominant source-side gate oxide degradation in CHE-stressed deep submicrometer n-MOSFETs

A possible mechanism behind the predominant source-side gate oxide degradation in channel hot-electron (CHE)-stressed deep submicrometer n-MOSFETs is presented. The role of a nonlocal hot-electron injection mechanism, arising possibly from carrier-to-carrier interaction and/or impact ionization feedback, is emphasized. The latter effect is prominently revealed through a systematic stress scheme that employs a reverse substrate bias. Oxide degradation behaviour is shown to be consistent with the anode electron-energy model. The more severe source-side oxide degradation may be attributed to nonlocally injected tertiary electrons possessing greater available energy on arrival at the anode (gate), as a result of a coupled heating process.