The work presents the results of a research on the photoacoustic spectra of thin surface layers of Cd_1−xBe_xTe crystals formed by grinding and polishing their surfaces. As a result of matching the theoretical and experimental photoacoustic spectra, thermal and optical parameters of these layers were determined. Thermal parameters of the surface layers, such as thermal conductivity and thermal diffusivity, turned out to be much worse than the analogous parameters of the substrate. The increase in the optical absorption of surface layers for photon energies below E_g was also determined.

E_g was also determined.