Modeling recombination and contact resistance of poly‐Si junctions
Nils Folchert, Robby Peibst, Rolf Brendel
Abstract
Abstract We present a semi‐analytical model for the calculation of the current through and the recombination in carrier‐selective junctions consisting of a poly‐Si/SiO x /c‐Si layer stack. We calculate the recombination parameter J 0 and the contact resistance ρ C after solving the band‐bending‐problem on both sides of the interfacial oxide. Comparisons with finite‐element simulations show that the current calculation is reliable at all bias conditions except for inversion and that current through pinholes is resolved adequately in the model. The model allows a coherent description of lifetime‐, current‐voltage‐ and capacitance‐voltage measurements performed on a sample with dominant tunneling. We use our model to investigate the influence of oxide thickness and pinhole density on J 0 and ρ C of our state‐of‐the‐art poly‐silicon‐on‐oxide (POLO) junctions and demonstrate its usefulness for the optimization of poly‐Si based junctions.