Crystal orientation control with a continuous-wave laser for ultra-high mobility silicon thin film transistors

Abstract

Highly bi-axially oriented poly-Si thin films were successfully fabricated on quartz substrates by multi-line beam continuous wave laser crystallization. The crystallinity was controlled to be {211}-{110}-{111} or {100}-{100}-{100} crystal grains by changing the laser-crystallization conditions. By using the {100} poly-Si thin film, ultra-high mobility poly-Si TFTs were demonstrated. The highest field effect mobility was 1010 cm²/Vs. The relationship between the mobility and the TFT channel’s crystallinity was also investigated.