Crystallographic and Micrographic Structure of Copper Indium Gallium diSelenide (CIGS) Semiconductor Thin Films using Chemical Bath Deposition (CBD) Technique

CIGS semiconductor thin films have been deposited successfully on microscopic glass substrates using Chemical Bath Deposition (CBD) technique at 85C. The mixture for the CIGS baths were prepared by mixing 10ml of 0.3 M of CuCl2. H2O and 5ml of TEA in a 50ml beaker, 10ml of 0.2 M of InCl3.4H2O, 10ml of 0.4 M of GaCl3 complexed with 5 ml of 0.5M EDTA in a 100 ml beaker and this step was repeated for 0.6 M and 0.8 M of GaCl3 for 1: 2, 1: 3 and 1: 4 In: Ga ion concentrations ratio respectively. The crystallographic (structural) and morphological (micrographic) properties of the as-deposited and annealed CIGS films at 450 C temperature have been studied with aid of X-ray diffractometer and Scanning Electron Micrograph (SEM) machine respectively. The compositional and chemical analyses of the films were determined using X-ray Fluorescent (XRF) spectroscopy (Sky Ray Explorer). The crystalline nature of the CIGS (both 1: 2 and 1: 3) thin films were established, indicating that the as-deposited films were amorphous in nature whereas their respective annealed films were crystalline in nature which showed the effect of annealing on the samples. The XRF analysis confirmed the presence of CIGS and other elements in the deposited films. The SEM micrograph of the CIGS (1: 2) thin films showed a coarse distributed structure and finely distributed structure for as-deposited and annealed films respectively but as-deposited CIGS (1: 3) showed isolated spongy spots and pinholes while its annealed film showed reduced pinholes and relatively fine structural outlook.