Gate-self-aligned p-channel germanium MISFETs

The authors have fabricated the first gate-self-aligned germanium MISFETs and have obtained record transconductance for germanium FETs. The devices fabricated are p-channel, inversion-mode germanium MISFETs. A germanium-oxynitride gate dielectric is used and aluminum gates, serve as the mask for self-aligned source and drain implants. A maximum room-temperature transconductance of 104 mS/mm was measured for a 0.6- mu m gate length. A hole inversion channel mobility of 640 cm/sup 2//V-s was calculated using transconductance and capacitance data from long-channel devices. This large hole channel mobility suggests that germanium may be an attractive candidate for CMOS technology.<>