HOT-CARRIER RELIABILITY OF N-CHANNEL AND P-CHANNEL MOSFETS WITH POLYSILICON AND CVD TUNGSTEN-POLYCIDE GATE

Under maximum substrate current (I-sub,I-max) stress, tungsten-polycid e gate (WSix) n-MOSFETs are more resistant to hot-carrier degradation than polysilicon gate (PolySi) devices. However, under maximum gate cu rrent (I-g,I-max) stress, WSix n-MOSFETs degrade more severely. WSix p -MOSFETs degrade more than the PolySi p-MOSFETs under both the I-sub,I -max and I-g,I-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. Copyri ght (C) 1996 Elsevier Science Ltd