In this study, a new thin-film deposition process, spray coating method (SPM), was investigated to deposit the high-densified CuInSe 2 absorber layers. The spray coating method developed in this study was a non-vacuum process, based on dispersed nano-scale CuInSe 2 precursor and could offer a simple, inexpensive, and alternative formation technology for CuInSe 2 absorber layers. After spraying on Mo/glass substrates, the CuInSe 2 thin films were annealed at 550 °C by changing the annealing time from 5 min to 30 min in a selenization furnace, using N 2 as atmosphere. When the CuInSe 2 thin films were annealed, without extra Se or H 2Se gas used as the compensation source during the annealing process. The aim of this project was to investigate the influence of annealing time on the densification and crystallization of the CuInSe 2 absorber layers to optimize the quality for cost effective solar cell production. The thickness of the CuInSe 2 absorber layers could be controlled as the volume of used dispersed CuInSe 2-isopropyl alcohol solution was controlled. In this work, X-ray diffraction patterns, field emission scanning electron microscopy, and Hall parameter measurements were performed in order to verify the quality of the CuInSe 2 absorber layers obtained by the Spray Coating Method.
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