Loss Factors and Efficiency             
          of Semiconductor
Photovoltaic electricity could be produced at a cost of  $0.031 ~ 0.039kWh
Solar cell
Loss factor in plants
  Major loss factors in semiconductor
Loss factor in silicon cell
Minimizing two major loss factor
Multiple band gap cell
Multiple band gap structure
Multiple band gap cell (experiment)
Multiple band gap cell quantum efficiency
Energy Gap
Amorphous silicon
Future research
Article about growing multi-band gap