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

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 (Φ
_Bn
) of 0.69 eV for electrons, resulting in a high junction current ratio of more than 10
⁵
at the applied voltage of |Va| = 1 V. Our quantum-well pMOSFET exhibited a high I
_ON
/I
_OFF
ratio of ~10
⁷
(I
_S
) and a moderate subthreshold swing of 166 mV/decade.