Growth and study of CuIn_1−xGa_xSe₂ chalcopyrite compounds for solar cell applications

In this work structural, optical and electrical properties of CuIn_0.8Ga_0.2Se₂ and CuIn_0.5Ga_0.5Se₂ compounds in both ingots and thin film forms are investigated. Peaks obtained by X ray diffraction are analyzed and calculated value of c/a ≈ 2 shows that prepared samples are of chalcopyrite structure. Gap (Eg) and resistivity (ρ) of CuIn_0.5Ga_0.5Se₂ thin films are slightly high, whereas CuIn_0.8Ga_0.2Se₂ thin films with values of Eg = 1.16 eV and ρ = 2.4 Ω cm indicate that CuIn_0.8Ga_0.2Se₂ compound is suitable for fabrication of high efficiency solar cells. (author)