FABRICATION OF P-CHANNEL MOS TFTS ON RAPID THERMAL CVD POLYCRYSTALLINE SILICON-GERMANIUM FILMS

P-channel metal-oxide-semiconductor (PMOS) thin-film transistors (TFT' s) have been fabricated on rapid thermal chemical vapor deposition (RT CVD) polycrystalline silicon-germanium (poly-Si0.82Ge0.18) films for t he first time. The transistors with a channel length of 1.5 mu m exhib it good electrical characteristics. The device performance is degraded in proportion to oxygen content, based on measurements using secondar y ion mass spectrometry (SIMS). After electron cyclotron resonance (EC R) plasma hydrogenation under optimal conditions, the density of trap states is markedly decreased in short-channel devices, resulting in re latively low leakage current (similar to 12.1pA/mu m) and high field-e ffect hole mobility (similar to 13.4cm(2)/V . s).