Crystallizing amorphous silicon film by using femtosecond laser pulses

Abstract

In order to investigate the non-thermal ultrafast crystallization process, amorphous silicon films on two different substrates were subjected to femtosecond laser pulses. Phase transition was demonstrated by forming a new peak in Raman spectroscopy corresponding to single-crystalline silicon phase under stress. Surface morphologies of the pristine and processed amorphous silicon film were characterized by SEM and AFM, confirming the formation of nanocrystalline silicon. The ultrafast phase transition process were comparatively investigated on single-crystalline silicon substrates with and without cover oxide layer, indicating the non-thermal crystallizing amorphous silicon process via femtosecond laser pulses.