A series of microcrystalline silicon thin films solar cells were fabricated by very high frequency plasma enhanced chemical vapor deposition at different total gas flow rates and on different back reflectors. The results of I-V measurements of solar cells showed that the characteristic parameters of solar cells were all improved with the increase of total flow rate, so conversion efficiency of solar cells were increased. In addition, short circuit current (Jsc) of solar cells was greatly reduced, as a result, conversion efficiency of solar cells were improved when ZnO/Ag/Al back reflector were incorporated into solar cells. The details can be seen in the paper.