The　hydrogenated　amorphous　silicon　(a-Si:H)　manufactured　by　plasma　deposition　techniques　has　been　extensively　investigated　as　a　low-cost　material　used　for　solar　cells　production,　during　which　its　photovoltaic　properties　are　strongly　dependent　on　the　H　content　and　various　H-Si　bonding　configurations　closely　related　to　the　experiment　parameters.　In　this　study,　samples　are　deposited　using　microwave　electron　cyclotron　resonance　chemical　vapor　deposition　(MW　ECR　CVD)　system　assisted　by　hot　filament.　The　parameters　are　adjusted　to　improve　the　deposition　rate　(DR)　and　photosensitivity　(σph/σD)　of　a-Si:H　thin　films　and　infrared　spectroscopy　is　utilized　to　determine　the　H　content　and　H-Si　configuration.　It　is　suggested　that　in　this　system,　the　higher　temperature　caused　by　the　energetic　bombardment　of　ions　and　radiation　of　hot　filament　is,　the　higher　value　of　σph/σD　is　obtained,　and　meanwhile　the　photo-electric　properties　of　a-Si:H　films　are　improved　by　chemical　etching　of　weak　Si-Si　bonds　when　the　H2　dilution　ratio　is　increased　for　the　last　few　minutes　during　the　film　deposition.