Laser wavelength dependences of amorphization and crystalization of Si by femtosecond laser pulses

In addition to the non-thermal ablation and the LIPSS (Laser Induced Periodic Surface Structures) formation, it had been reported that femtosecond laser irradiation induced amorphization of crystalline semiconductor [1,2] and crystallization of amorphous Si [3,4]. By controlling laser fluence far below the ablation threshold, we can change the crystalline structure of the semiconductors. In this paper, we are reporting the laser wavelength dependences of the phase transition of Si by femtosecond laser pulses.