The microstructure of silicon thin films fabricated at low temperature by plasma enhanced chemical vapor deposition(PECVD) using H2/SiH4 has been studied by Raman scattering.The results show that substrate temperature plays an important role in depositing process.And there is a best temperature point of 400 ℃ for crystallization between 200 ℃ to 500 ℃.The silicon thin films are easy to crystallize under high-pressure and high-power deposition process compared with conventional conditions.The grain size of s...