ABSTRACT
A recent trend toward development of nanocrystalline silicon (nc-Si) lies in preparing nc-Si thin films exhibiting strong photoluminescence, based on a quantum size effect. This technique is expected to have a potential for application to optoelectronics. Formation of nc-Si structures has been tried utilizing various techniques: anodic oxidation of crystalline Si, that is, formation of porous Si formation of nc-Si thin films using plasma-enhanced chemical vapor deposition (PECVD), sputtering, evaporation, and ion beam synthesis. In the case of PECVD nc-Si thin films deposited using SiH4/SiF4/H2 gas mixtures, the etching effects of H- and F-radicals in plasma will play important roles. Such etching effects may result in different mechanisms that affect crystallinity. The chapter focuses on the mechanisms of crystallization, through the understanding of the roles of H and F atoms in plasma under different plasma conditions.
