Investigation of Si thin films Recrystallization Mechanism during Excimer Laser Annealing Using In-situ Time-Resolved Optical Reflection and Transmission Measurement

• Main Authors: Chia-Bin Chen, 陳佳斌
• Other Authors: Jeng-Ywan Jeng
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/02618242250394284806

碩士 === 國立臺灣科技大學 === 機械工程系 === 93 === An in-situ real-time time-resolved optical reflectivity and transmissi vity (TRORT) monitoring system combining a CW He-Ne laser, a fast digital oscilloscope and two photodiodes is developed for monitoring the melt-phase duration and examine the melting and crystallization behavior during XeF excimer laser annealing(ELA) in this study. The recrystallization models are proposed to interpret the formation of grain microstructure. The melt-phase duration of PECVD-grown 90nm-thick a-Si films during ELA is increased from partial melting with 15 ns to complete melting with 130 ns. The grain size of 1μm in diameter is found in the super lateral growth SLG regime with melt-phase duration with 110 ns .Thickness of a-Si greater than 50 nm, pulse duration of excimer laser greater than 25 ns and wavelength of excimer laser greater than 248 nm are important for triggering the EC during ELA. Surface roughness of the sample smaller than 1 nm of root mean square (RMS), wavelength of probe laser greater than 633 nm and output power of probe laser greater than 5 mW are easier to observe the EC phenomenon using TRORT measurements during ELA. This technique provides a simple approach for fabrication large-grained poly-Si during ELA and enhances the high yield during in-line large area flat panel displays fabrication using poly-Si TFTs.