For the first time, we report a low temperature silicon thin film deposition technology using high density plasma for high performance and low cost solar cells with embedded transistor modules. For process temperature at 140°C, energy conversion efficiency of 9.6% and electron mobility of 1.1 cm
/V-s have been achieved. Device performance with process temperature down to 90°C and 60°C has also been examined in depth. This very low process temperature technology can integrate energy harvesting with electronics on inexpensive and flexible substrates.