Comparative experimental study of laser-induced transitions in crystalline silicon by femtosecond, picosecond, and millisecond laser ablation

Abstract

In order to study laser-induced transitions of the crystalline silicon, comparative ablation experiments by femtosecond-, picosecond-, and millisecond-pulsed laser were carried out on<111>crystalline silicon wafers in this study. For each laser ablating process, final chemical composition and microstructural state of ablated material on sample surface were analyzed by X-ray photoelectron spectroscopy and transmission electron microscopy, respectively. Then the influences of laser pulse duration variation on the composition and microstructure of ablated material were also discussed. Therefore, the experimental results were considered to provide more completed and further understandings of laser-induced transitions of crystalline silicon, which may have some contribution to the development of laser-semiconductors micromachining.

Keywords:

• laser-induced transitions
• crystalline silicon
• variation of laser pulse duration
• chemical composition
• microstructural state

Acknowledgements

This work was supported by National Natural Science Foundation of China (grant no. 91123024), Program for Changjiang Scholars and Innovative Research Team in University (grant no. IRT1172) and the Fundamental Research Funds for the Central Universities. The authors greatly appreciate the fruitful and congenial collaboration with B. Liu, W.Q. Duan, and T. Chen.