Schulze, T.F. ; Korte, L. ; von Maydell, K. ; Schmidt, M. ; Rech, B.: Insight Into Electronic Transport and Interface Passivation in a-Si:H/c-Si Heterojunction Solar Cells by Temperature-dependent I-V Characterization. In: 24th European Photovoltaic Solar Energy Conference, EU PVSEC ; proceedings of the international conference, held in Hamburg, Germany, 21 - 25 September 2009Munich: WIP, 2009, p. 2213-2217
Abstract:
We present measurements of temperature-dependent dark I-V curves on (n)a-Si:H/(p)c-Si heterojunction solar cells with varying doping concentration and with or without a back-surface field. From fitting of the I-V data we obtain saturation current densities, activation energies and diode ideality factors which we analyze to gain insight in the dominant transport regimes and the interface passivation. Flanking the dark I-V analysis withphotoluminescence, photoelectron spectroscopy and surface photovoltage data we show that upon raising the emitter doping level above 2000 ppm, the interface passivation increasingly deteriorates and the Fermi level is pinned in the interface defects.