上海文通大学 SHANGHAI JIAO TONG UNIVERSITY Solar Cells Background Photovoltaic effect Proper band gap size Silicon as a semi-conductor conduction electron Abundance,cost,efficiency band ·Needs doping and band gap electron or solar energy forbidden photon metal contacts energy gap textured surface front contact AR coat ME emitter n si front contact valence band hole base PSi heat Irear contact▪ Photovoltaic effect ▪ Proper band gap size ▪ Silicon as a semi-conductor ▪ Abundance, cost, efficiency ▪ Needs doping and metal contacts Solar Cells Background