Low-temperature-processed polycrystalline silicon thin-film transistors using titanium disilicide contacts for source and drain

Abstract

We propose a new process without source-drain doping for realization of low-temperature polycrystalline silicon (poly-Si) thin-film transistors (TFT's). The process is based on TiSi2 contacts for source and drain. Titanium disilicide was formed by in situ silicidation using high-temperature magnetron sputtering at 450 degrees C. The new device has demonstrated better leakage characteristics (similar to 0.4 pA/mu m) and slightly lower ON current compared with standard-processed devices having phosphorus-doped source and drain with a dose of 1 x 10(14) cm(-2). The field-effect mobility (similar to 10 cm(2)/V . s) and I-on/I-off current ratio (similar to 1.2 x 10(6)) are comparable to those of standard-processed devices.