Quarternair CuGaSeTe and CuGa0.5In 0.5Te2 Thin Films Fabrication Using Flash Evaporation. Quarternairmaterials CuGaSeTe and CuGa0.5In 0.5Te2 are the basic materials to solar cell fabrication. These materials have highabsorption coefficients around 103 - 105 cm-1 and band gap energy in the range of 1-5 eV. In this research, the filmswere made by flash evaporation method using quarternair powder materials of CuGaSeTe and CuGa0.5In 0.5Te2 toadhere in a glass substrate. After the films were obtained, the properties of these films will be characterized opticallyand electrically. The lattice parameter of the films and the crystalline film structure were obtained using X-RayDiffraction (XRD) spectroscopy. The XRD results show that the quarternair CuGaSeTe and CuGa0.5In 0.5Te2 films havea chalcopyrite structure. The absorption coefficient and the band gap energy of the films were calculated usingtransmittance and reflectance patterns that measured using UV-VIS Difractometer. The films composition can bedetected by using the Energy Dispersive Spectroscopy (EDS), while the films resistivity, mobility and the majoritycarrier of the films were obtained from Hall Effect experiments.