| Summary: | 碩士 === 長庚大學 === 電子工程學系 === 100 === In this thesis, we prepare the CIGS absorber layer by two step methods, sputter and selenization. First, the CIG precursor films with different stack order were deposited by sputtering CuGa binary target and In target. Then, the precursor was selenized by the temperature profiles of three steps in Se vapor environments. In the stack layer experiment, we prepare three types of precursor structure, CuGa/In, CuGa/In/CuGa and CuGa/In/CuGa/In. We observe that CuGa/In/CuGa/In structure have denser, smoother and more uniform surface from SEM characterization, and the FWHM of chalcopyrite phase(112) is about 0.2 from XRD measurements. Raman spectroscopy shows the Cu2-xSe secondary phase at 260cm-1, which can be successfully eliminated by KCN etching. In the structure of CuGa/In/CuGa precursor, we change the thickness ratio of top and bottom CuGa layer. When the thickness ratio is 1:1.4, it can grow the smoother and denser surface. The CGI and GGI ratios are 0.83 and 0.19 respectively. Further, we discuss the reaction mechanism of selenization process. It is found that the Cu11In9 phase have a strong orientation in the first temperature step of 175℃. In the second temperature step of 350℃, we observe a strong diffraction peak of the CIS phase. In addition, the Cu3Ga phase completely disappears. It indicates that selenium has been completely diffused into the bottom CuGa layer to form CuGa and selenium compounds, like Cu2Se and Ga2Se3 etc.
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