Formation of homo- and hetero-interfaces in CdxHg1−xTe solid solutions by pulse laser irradiation

Abstract

Comprehensive investigations were made of the photoconductivity, photomagnetic effect, magnetic field dependences of the Hall coefficient and of the relative conductivity in n- and p-type CdxHg1−xTe (CMT) solid solutions, which were irradiated with nanosecond ruby laser pulses. The samples were distinguished by both the structural and the component composition. Irradiation of CMT with subthreshold energy density modified the point-defect structure in the surface layer and improved homogeneity. An increase in the energy density shifted the maximum and the long-wavelength edge of the photoconductivity spectra toward shorter wavelengths and increased the photosensitivity of the epitaxial CMT layers with a cellular structure. Laser irradiation resulted in formation of an acceptor enriched layer in surface region of CMT samples. In the case of n-type crystals a conduction type inversion occurred and a built-in p-n junction arose; in p-type CMT epitaxial films p+-p junction arose under the action of nanosecond laser pulses.