| Summary: | 碩士 === 南台科技大學 === 光電工程系 === 98 === In recent years, due to the energy shortage and global warming lead the green energy issues become very important. The researches in Thin Film Solar Cells received a lot of attentions. To fabricate amorphous silicon thin film solar cells using plasma-enhanced chemical vapor deposition (PECVD) is the most popular method. The disadvantages of PECVD are the high facility cost and using the toxic processing gases such as silane (SiH4). Whereas there is no these disadvantages using ion beam sputter system to deposit silicon thin films. Hydrogenated amorphous silicon thin films have attracted many attentions due to have high mobility and less defect density than the amorphous silicon (a-Si) thin films. In this study, the hydrogenated amorphous silicon (a-Si:H) thin films were fabricated using ion beam sputter system of which the low sputter yield to reduce defect density and correctly control deposited thin films. Therefore, it is a appropriate tool to explore the properties of hydrogenated amorphous silicon (a-Si:H) thin films with the absorption coefficient of 105cm-1. (a-Si:H) thin films were fabricated using different process temperatures and the hydrogen gas flows. The characteristics of deposited film were measured by FTIR, Micro-Raman Spectrometer, UV/Visible spectrometers. The results showed absorptance of the film were reached 40~50% at wavelength of 400nm. The photo energy gap were varied from 1.7~2.0eV depending on the structure of films. The silicon films deposited by ion beam sputter revealed amorphous characters .When the substrate temperature was set at 350℃and hydrogen gas flow was set as 10sccm would favor the formation Si-H2 bond. The analyses of the electrical property show that the dark and photo induced current decreased with increased substrate temperature and hydrogen gas flows.
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