High-Performance Schottky Contact Quantum-Well Germanium Channel pMOSFET With Low Thermal Budget Process

Abstract

We present a high-performance Si/Ge/Si p-channel metal–oxide–semiconductor field-effect transistor (pMOSFET) with a NiSiGe Schottky junction source/drain (S/D) formed through microwave-activated annealing. A Schottky contact S/D is preferable, because the lower process temperature is beneficial for eliminating Ge diffusion. The fabricated NiSiGe Schottky junction exhibited a high effective barrier height ( $\Phi _{\textrm {Bn}}$ ) of 0.69 eV for electrons, resulting in a high junction current ratio of more than $10^{5}$ at the applied voltage of $|V_{a}|=1$ V. Our quantum-well pMOSFET exhibited a high $I_{\mathrm{\scriptscriptstyle ON}}/I_{\mathrm{\scriptscriptstyle OFF}}$ ratio of $\sim 10^{7}$ ( $I_{S}$ ) and a moderate subthreshold swing of 166 mV/decade.