Comprehensive simulation model for Cu(In,Ga)(Se,S)2 solar cells

Abstract The modeling of Cu(In,Ga)(Se,S) 2 thin film solar cells enables us to understand device behavior while a reliable simulation with forecasting purpose needs to cover manifold measurement responses. We built up a simulation model to reproduce thermal admittance spectra, capacitance–voltage profiles, quantum efficiency and current–voltage ( I–V ) measurements in a broad temperature range from 130 K to 330 K with one parameter set. The comprehensive optical and electrical simulation model has been created as baseline for an indium sulfide buffered Cu(In,Ga)(Se,S) 2 solar cell based on measurement outcome and material characterization. The model ascribes the observed N1 feature ascribing it to a valence band barrier between Cu(In,Ga)(Se,S) 2 and Mo(Se,S) 2 back contact which is also responsible for the roll-over behavior in I–V measurements. A highly doped p + layer near the heterointerface is accountable for superposition failure of dark and light I–V curves and kink shape at low temperatures. Two-dimensional simulations further show roll-over dependence on back contact inhomogeneities due to sulfur fluctuations.