Heterojunctions in the n-CdTe-p-ZnTe system were prepared via solid-state s
ubstitutions, and their properties were studied. Under small forward bias,
the current-voltage characteristics of the heterojunctions, both in the dar
k and under illumination, are dominated by the generation-recombination pro
cesses in the space-charge region. The spectral response of the heterojunct
ions extends from the band gap of CdTe to that of ZnTe.