This work investigated the ion implantation induced solid phase epitaxy (SPE) of Si thin films prepared by low pressure chemical vapor deposition (LPCVD). Previous studies indicate that the residual layer at the interface between the Si thin film and single crystalline substrate is the major obstacle to the SPE process of Si film. In this work, Ge+ and Si+ ion were implanted to completely amorphize the Si film prepared by LPCVD. Ion implantation also mixed the interfacial oxide layer and its effects on subsequent epitaxial growth of Si film subjected to various annealing conditions were discussed as well. In addition, the specimen surface was modified by inductive couple plasma (ICP) process. The ICP modification using nitrogen gas could form a vacancy source on the sample surface to enhance the atomic diffusion rate and change the stress state in the vicinity of surface, thereby accelerating the SPE process.