Measured and simulated dark J-V characteristics of a-Si:H single junction p-i-n solar cells irradiated with 40 keV electrons

The effect of 40 keV electron irradiation on a-Si:H p-i-n single-junction solar cells was investigated using measured and simulated dark J-V characteristics. EPRI-AMPS and PC-1D simulators were explored for use in the studies. The EPRI-AMPS simulator was employed and simulator parameters selected to produce agreement with measured J-V characteristics. Three current mechanisms were evident in the measured dark J-V characteristics after electron irradiation, namely, injection, shunting and a term of the form CV^m. Using discrete energy states at the center of the band gap, good agreement was achieved between measured and simulated J-V characteristics in the forward-bias voltage region where the dark current density was dominated by injection. Some evidence of the CV^m term is present in device simulations with a higher density of states located at the center of the bandgap.