High-performance thin-film transistors using Ni silicide for liquid-crystal displays

摘要

The Ni-silicide of a sheet resistance of 7 OMEGA /square can be formed at 230 deg C on n~+ a-Si:H and thus can be aplied to gate and source/drainc ontacts for high performance TFTs. Because of its low resistance it is possible to make a self-alignment between gate and source/drain, which lead to a coplanar a-Si:H TFT having a low parasitic capacitance between them. The NiSi_2 precipitates can be formed on a-Si:H at around 350 deg C and needlelike Si crystallites are grown as a result of the migration of the NiSi_2 precipitates though a-Si:H network. Amorphous silicon can be crystallized at 500 deg C in 10 minutes in a modest electric field. The low temperature poly-Si TFT with a field effect mobility of 120 cm~2/Vs has been demonstrated using the low temperature poly-Si.