Photovoltaic cells with efficiency exceeding 10% using monocrystalline CuInSe2 substrates

Photovoltaic cells with the structure of ZnO/CdS/CuInSe₂ have been fabricated on single crystal CuInSe ₂ substrates obtained from p-type Bridgman-grown ingots. A chemical bath method was used to deposit the CdS film onto the abrasively-polished CuInSe₂ substrates while RF sputtering was employed for the ZnO deposition. It was found that the performance of these cells were dominated by the high density of surface defects, which could be reduced by a substrate annealing prior to the CdS deposition. A conversion efficiency of 10.3% at about AM 1.5 under the Sun has been achieved on solar cells with an effective area of 8 mm². An antireflection coating was not used in the present case