Laser-processed thin-film transistors fabricated from sputtered amorphous-silicon films

Abstract

Low-temperature polysilicon thin-film transistors (TFTs) have been fabricated from sputtered silicon films and characterized as a function of as-deposited hydrogen (H) content and laser crystallization fluence. A general trend is observed where TFT performance improves as the H content is lowered. Devices made from -0% H sputtered films perform similar to those made from low-pressure chemical-vapor deposition processes (LPCVD), but are fabricated at a much lower processing temperature (300/spl deg/C). The best sputtered TFTs had mobilities of -200 cm2/Vs, and on/off current ratios of more that 10/sup 8/.