The deposition parameters of microcrystalline thin films by RF-PECVD and VHF-PECVD are systematically studied.Under similar conditions,the deposition rate of μc-Si:H thin films is higher by VHF-PECVD than by RF-PECVD.With deposition rate successively enhanced by VHF-PECVD,μc-Si:H solar cell efficiency is also improved.Generally,when deposition rate increases,dangling bonds related defects also increase,which is detrimental to solar cell performance.In order to increase deposition rate while keeping defects low,the deposition parameters are thoroughly investigated.Kept the deposition parameters as 0.75 nm/s,μc-Si:H solar cells are also fabricated and an initial efficiency of 5.41% is achieved.