Hot-carrier reliability of n- and p-channel MOSFETs with polysilicon and CVD tungsten-polycide gate

Abstract

Under maximum substrate current (Isub,max) stress, tungsten-polycide gate (WSix) n-MOSFETs are more resistant to hot-carrier degradation than polysilicon gate (PolySi) devices. However, under maximum gate current (Ig,max) stress, WSix n-MOSFETs degrade more severely. WSix p-MOSFETs degrade more than the PolySi p-MOSFETs under both the Isub,max and Ig,max stress. An explanation substantiated by the charge-pumping measurements is proposed. The hot-carrier lifetimes of WSix n-MOSFETs are found to be higher than that of the WSix p-MOSFETs. Copyright © 1996 Elsevier Science Ltd.