Germanium p-Channel FinFET Fabricated by Aspect Ratio Trapping

摘要

We report scaled Ge p-channel FinFETs fabricated on a 300-mm Si wafer using the aspect-ratio-trapping technique. For long-channel devices, a combination of a trap-assisted tunneling and a band-to-band tunneling leakage mechanism is responsible for an elevated bulk current limiting the OFF-state drain current. However, the latter can be mitigated by device design. We report low long-channel subthreshold swing of 76 mV/decade at $V_{rm DS}=-0.5~{rm V}$, good short-channel effect control, and high transconductance ($g_{m}=1.2~{rm mS}/mu{rm m}$ at $V_{rm DS}=-1~{rm V}$ and 1.05 ${rm mS}/mu{rm m}$ at $V_{rm DS}=-0.5~{rm V}$ for $L_{G}=70~{rm nm}$). The Ge FinFET presented in this paper exhibits the highest $g_{m}/{rm SS}_{rm sat}$ at $V_{rm DD}=1~{rm V}$ reported for nonplanar unstrained Ge p-FETs to date.