Photosensitivity increase of vapor-phase graded band gap CdHgTe by introduction to substrate of an isovalent impurity Mn,Zn

Abstract

By using the method of VPE CdMnTe-CdMnHgTe, CdZnTe-CdZnHgTe heterocompositions were fabricated. The increase of their photo-sensitivity in comparison with the CdTe-CdHgTe structure is explained by removal of deformation stresses due to the introduction of an isovalent component (Mn, Zn) of smaller size and due to reduction of recombination activity of non-equilibrium charge carriers in the film. The photo-sensitivity increase in the field of the metallurgical boundary in the CdMnTe-CdMnHgTe structure under increase of the Mn content up to /spl gamma//spl les/0.08 in comparison to the CdZnTe-CdZnHgTe structure is connected with the more precise matching of the lattices of the initial materials. On the basis of comparisons of experimental and calculated profiles of the component distribution, the values of diffusion coefficients in the substrate and growing film were obtained.