Laser Annealing of LTPS

摘要

Laser annealing has become the primary method for producing the Low-Temperature-Poly-Silicon (LTPS) panels used in the Flat Panel Display (FPD) industry. Thin Film Transistor (TFT) backplanes based on LTPS substrates for Active Matrix Liquid Crystal Displays (AMLCD) offer substantial advantages over TFT backplanes based on amorphous silicon. The trend to higher pixel density, the integration of more driver and logic ICs on the glass, and the advent of Active Matrix Organic Light Emitting Displays (AMOLED) all have lead to significant interest in the laser annealing process. Currently, there are several different approaches to the annealing process based on excimer lasers, cw-green DPSS lasers, modelocked-green DPSS lasers and Q-switched Nd:YAG lasers. This paper reviews the various laser technologies and annealing techniques, such as the line beam method and Sequential-Lateral-Solidification (SLS). These approaches will be compared in terms of crystal quality, electron mobility, throughput, yield and operating cost.