Enlargement of Poly-Si Film Grain Size by Excimer Laser Annealing and Its Application to High-Performance Poly-Si Thin Film Transistor

Abstract

By both numerical simulation and experimental investigation, we found it possible to enlarge the grain size (∼3000 Å) of polycrystalline silicon (poly-Si) films by excimer laser annealing, using a new method to control the solidification process of molten Si - low-temperature (≦400°C) substrate heating during laser annealing. Poly-Si thin-film transistors (TFTs) fabricated by this new excimer laser annealing method showed a high field-effect mobility of 230 cm 2 /V·s, and good uniformity of field-effect mobility (±10%) within the effective laser irradiation area.