M. Boostandoost, U. Kerst, Technische Universität Berlin, Berlin, Germany; C. Boit, Berlin University of Technology, Berlin, Germany

Summary: The temperature dependence of photocurrent of polycrystalline Si (poly-Si) thin film solar cells on glass with interdigitated mesa structure, have been locally investigated using Infrared Light Beam Induced Current (IR-LBIC) in the range of 10 – 60 °C. The temperature dependence of electrical characteristics of poly-Si thin film solar cells in reverse bias has been also analyzed and compared with the monocrystalline solar cells. The a-Si/poly-Si solar cell shows a temperature coefficient (TC) for photocurrent of around +0.5 to +0.7 %/°C. The activation energy of reverse current and induced photocurrent by IR light in a-Si/poly-Si thin film solar cell have been evaluated, which provide us information about defects and their energy levels in the absorber layer of poly-Si thin film solar cell. The obtained activation energy for a-Si/poly-Si suggests the existence of a shallow acceptor level at around 0.06 eV in the grain boundary of the absorber layer of a-Si/poly-Si solar cell.