Vlasov A. Preparation and properties of doped epitaxial layers CdXHg1-XTe

The work is concerned with the study of mechanisms of diffusion and activation of acceptor impurity As or Sb in variable band-gap structures of CdXHg1-XTe during the vapour-phase epitaxy or thermal annealing. Coefficients of As diffusion in narrow-gap CdXHg1-XTe under the annealing temperatures higher than 500°С have been calculated and their dependency on concentration has been determined. The possibility of diffusion of As into CdXHg1-XTe by the way of creation of triple-ionised impurity complexes (AsHgVHg)/// is demonstrated. Coordinate dependencies of As concentration in variable band-gap CdXHg1-XTe structures have been studied, and it has been shown, that the shape of diffusion profiles of the impurity results from the existence of built-in electrical field in these structures. Examples of creation of IR photo-voltaic detectors on the basis of doped variable band-gap structures CdXHg1-XTe are given. Results are used in the search and elaboration of new devices for IR- photoelectronics.