Preparation and analysis of Cu(In,Ga)Se2 thin-film made by co-sputtering for CdS-free solar cell device

• Main Authors: Yu-Tang Qiu, 邱郁棠
• Other Authors: Dong-Hau Kuo
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/3hj5rb

碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 104 === In recent years, confronting with the problem of energy crisis, Cu(InGa)Se2 or CIGSe thin-film solar cells are gradually getting researchers’ attentions. In this field, solar cell device almost uses CdS as a buffer layer and ZnO as a n type one. Because CdS is toxic, GaN and InGaN in this work have been taken to replace CdS/ZnO for designing different solar cell structures. In the study, CIGSe precursor thin films were prepared by sputtering, followed by selenization with different annealing temperatures. The characterizations of thin films were analyzed by field-emission scanning electron microscopy (FE-SEM) epuipped with an energy dispersive X-ray spectrometer (EDS), X-ray diffractometry (XRD), and Hall measurement. Different Indium contents for InxGa1-xN that were used as n type layers for solar cell devices were also prepared by sputtering. The performance of the devices was then evaluated under the standard AM 1.5 illumination. The results showed that CIGSe thin films after made by co-sputtering and a two-step selenization process at 600oC had better surface morphology with the grain size of 1.0 – 1.5 m. FE-SEM, XRD and EDS analyses demonstrated that the films were single phase with the close component of CuIn0.7Ga0.3Se2 even selenization at different temperatures. Then, InxGa1-xN thin films made by RF sputtering replaced CdS as the buffer layer for the solar cell structure. CdS-free CIGSe/In0.15Ga0.85N/ZnO solar cell with the structure I had the best conversion efficiency of 1.04% conversion, while it was 3.07% for the traditional CIGSe/CdS/ZnO solar cell structure.