Temperature dependence of p-i-n HIT solar cell characteristics

The regional approximation method is used for calculating temperature dependent p-i-n a-Si/c-Si HIT (heterojunction with thin intrinsic layer) solar cell characteristics. The emphasis in the analysis is given to the mechanisms which dominantly govern the temperature dependence of HIT cell conversion efficiency. The current transport in a p-i-n HIT cell is suppressed by drift-diffusion limitations in the intrinsic layer and by large valence-band offset at the a-Si/c-Si heterojunction. With increasing temperature, the onset of transport limitations is shifted toward higher forward voltages, causing an enhanced transfer of photogenerated holes and resulting in a lower temperature dependence of HIT cell conversion efficiency.