Hydrogenation and annealing effects on the trapping times of the minority carriers in In-doped CdTe epitaxial layers grown on p-CdTe (211) substrates

The behavior of trapping times of minority carriers in In-doped CdTe films due to annealing and hydrogenation was investigated by photoconductivity measurements on as-grown, annealed and hydrogenated, and hydrogenated and annealed samples grown by molecular beam epitaxy. A relatively high photosensitivity was observed under excitation intensity and was found to be due to minority carrier trapping, the activation energy of which could be inferred from the temperature dependence of the PC decay times. Annealing alone had no effect on the photoresponse time, while remarkable reduction occurred with hydrogenation.