Auger electron spectroscopy, ellipsometry and photoluminescence investigations of Zn1−XBeXSe alloys

In this paper, properties of the Zn1−XBeXSe crystals grown from the melt by the high-pressure Bridgman method are reported. Spectroscopic ellipsometry has been used for determination of the complex dielectric function of Zn1−XBeXSe. On the basis of the photon energy dependence of the dielectric function, the energy gaps of alloys containing different beryllium concentrations have been evaluated. Measurements of the photoluminescence (PL) spectra allowed to find the excitonic gap in the investigated alloys. Auger electron spectroscopy (AES) with simultaneous argon ion sputtering has been used for determination of surface composition. AES investigations allowed to make predictions concerning distribution of particular elements in the samples.