The In/PbTe barrier structures with a thin intermediate insulating layer

Epitaxial n-PbTe layers were grown on BaF₂ {111} single-crystal substrates by hot-wall epitaxy from the gaseous phase. These layers were kept in atmospheric air for 15–30 days, after which In and protective BaF₂ layers were deposited. Current-voltage characteristics and photoelectric sensitivity spectra of the In/n-PbTe barrier structures were measured in the temperature range T=80–300 K. Based on the experimental results, a model of charge transport is suggested and the effective barrier height ? _b ^eff , the insulator layer thickness δ, and the surface-state density D _S are determined.