Thin-film transistors with polycrystalline silicon films prepared by two-step rapid thermal annealing

A novel two-step rapid thermal annealing (RTA) process has been developed t o significantly reduce the crystallization time for the solid-phase crystal lization (SPC) of amorphous silicon films. In comparison with the conventio nal SPC processes, it not only keeps a low thermal budget but also achieves a larger poly-Si film grain size than that obtained by one-step RTA, and e ven as large as that obtained by conventional furnace annealing (CFA). Furt hermore, poly-Si thin-film transistors fabricated by such a novel annealing scheme possess electrical characteristics superior to those obtained by on e-step RTA and comparable to those obtained by long-time CFA.