Rapid Thermal Annealing Technique for Polycrystalline Silicon Thin-Film Transistors

Abstract

The fundamental characteristics of a rapid thermal annealing (RTA) technique that has been applied to polycrystalline silicon thin-film transistors (poly-Si TFTs) have been investigated and short channel (less than 3 µ m) poly-Si TFTs have been achieved. The annealing characteristics of a thin silicon film on a transmissive substrate are entirely different from those of a silicon wafer. An arc lamp is essential as the RTA light source. A self-controlled effect in activation annealing was observed. Size and pattern density of silicon islands affect the uniformity of annealing. An absorption layer of a silicon film makes the use of RTA practical. A shift-register circuit composed of short channel TFTs was also evaluated.