Product Code: PIC2008_P238

Millisecond Pulse Laser Bending of Silicon
Authors:
Dongjiang WU, Dalian University of Technology; Peoples Republic of China
Guangyi Ma, Dalian University of Technology; Dalian Peoples Republic of China
Bo Yin, Dalian University of Technology; Dalian Peoples Republic of China
Dongming Guo, Dalian University of Technology; Dalian Peoples Republic of China
Presented at PICALO 2008

Experiment of bending silicon with Nd: YAG laser of millisecond pulse width was carried out. The influence of frequency and pulse width on the bending angle was investigated. It was found that the bending quality of silicon is better when pulse width, frequency is 2ms, 30Hz and 1.5ms, 40Hz respectively. In succession, the bending silicon surface properties were detected by optics microscope and Raman spectrum. The results indicated that the irradiated surface was distributed to fringe region, transition region and mainly irradiated region. Therefore the dislocation theory was used to analyze the reasons of causing slip line and stacking fault during the process of bending and analyzed the influence on bending.Finally, temperature distribution of silicon during process of laser bending was analyzed by Ansys software. The calculated results indicated that the intensive temperature vibration of one point was existed during process of scanning. In the later process of scanning, temperature gradient mechanism (TGM) and Buckling mechanism (BM) were proved to co-exist, and the bending relied on brittle-ductile transformation temperature. The time of thermal action was so long as the pulse width extension; likewise frequency caused a directive influence on the overlay and cooling time.