Effect of Substrate Temperature on the Structural, Optical, and Electrical Properties of Silver-indium-selenide Films Prepared by Using Laser Ablation

KrF pulse UV excimer laser ablation of films of AgInSe2 (AIS) onto the glass substrates kept at different temperature using a ultra-high-vacuum deposition system has been studied. The AIS target was synthesized from high-purity materials. The compositional stoichiometry was observed to be largely maintained in the films. This suggests that Pulse Laser Deposition can be used as technique for fabrication of ternary semi conducting films. The X-ray diffraction studies of the films show that the films are textured in the (112) direction. The c/a ratio of 1.93, which is indicative of distortion, confirms its tetragonally-distorted chalcopyrite structure. The structural, optical and electrical properties have been investigated as functions of the substrate temperature. An increase in substrate temperature results in a more ordered structure. Field emission scanning electron microscopy (FESEM) observations show more compactness and densely packed arrangements with increasing substrate temperature. The roughness of the film is found to increase at higher deposition temperatures. The optical studies of the films show that the optical band gap lies in the range 1.20 - 1.27, eV. The activation energy is in the range 0.0103 - 0.0556 eV.