Charge-transport mechanisms in heterostructures based on TiO2:Cr2O3 thin films

n-TiO₂:Cr₂O₃/p-Si anisotype heterostructures are fabricated by the deposition of a TiO₂: Cr₂O₃ film by electron-beam evaporation onto a polished polycrystalline silicon substrate. Their electrical properties are studied and the dominant charge-transport mechanisms are determined: multistage tunneling-recombination mechanism involving surface states at the TiO₂: Cr₂O₃/Si metallurgical interface under small forward biases and tunneling at biases exceeding 0.8 V. The reverse currents through the heterostructures under study are analyzed in terms of the single-stage tunneling mechanism of charge transport.