Fabrication and characterization of the lamellar ternary compounds GaxIn1−xSe

Abstract In the aim of extending the study of the ternary III–VI compounds which brought many information on the specific properties of the lamellar compounds, the fabrication and characterization of Ga x In 1− x Se solid solutions are investigated. Electron microprobe measurements show that the solid solution exists in the two extreme narrow ranges 0≤ x ≤0.2 and 0.9≤ x ≤1. In these ranges, the variations of the hexagonal crystallographic parameters a and c versus x are deduced from X-rays measurements. The energy gap variation versus composition is determined at toom temperature from three types of measurements: absorption, Kelvin method and photoconductivity spectra. All these results are in good agreement and the same linear variation is obtained in the two ranges of composition. Hall effect and resistivity measurements at room temperature allow a transport characterization of these compounds. The transition between InSe like, n type materials and GaSe like, p type materials occurs near x = 0.13.