Application of Microwave Plasma Gate Oxidation to Strained-Si/SiGe-on-Insulator

We have applied microwave-plasma oxidation at 400 °C to the gate oxide formation of a strained-Si/SiGe-on-insulator (SGOI) metal–oxide–semiconductor field-effect transistor (MOSFET). Application of low-temperature wet-O2 treatment to plasma oxide on strained-Si/Si0.85Ge0.15 significantly reduces the density of interface states and provides a 72% enhancement in transconductance compared with Si control devices. In the case of a thermally oxidized device, the junction leakage current was increased due to Ge condensation up to 50% Ge at the mesa island edge. On the other hand, the plasma oxide device showed a leakage current two orders of magnitude lower than that of the thermally oxidized device, owing to the suppression of the Ge condensation.