Research & Reviews: Journal of Material Sciences
MenuISSN:2321-6212
ISSN:2321-6212
Takumi Namba and Shizutoshi Ando
Tokyo University of Science, Japan
Posters & Accepted Abstracts: Res. Rev. J Mat. Sci
Silicon (Si)-based solar cells have a market share of more than 90%, and are expanding in this market. However, high purity Si is very expensive and would be the risks of short supply and price fluctuation. Recently, Cu(In.Ga)Se2(CIGS) based thin film solar cells have been attracted as high conversion efficiency as a high efficiency thin film solar cell of the next generation and achieved the highest conversion efficiency of 20% over. The top electrode material for CICS based solar cell is widely used ZnO:Al and is required to be low resistivity (under 10-3 Ωcm) and optical transparency (larger than 80% in transmittance). Moreover, the preparation of good crystallinity ZnO:Al thin films is expected for improvement of the conversion efficiency of CIGS based solar cells. In this study, we tried to prepare ZnO:Al thin films with good crystallinity by helicon wave excited magnetron sputtering method and aimed to establish conditions for preparation. ZnO:Al thin films prepared by this method were evaluated for crystallinity, optical transmittance, and thickness by X-ray diffraction (XRD), recording spectrophotometer, and stylus surface profiler. Figure1 shows (a) XRD patterns and (b) optical transmittance spectra of ZnO:Al thin films prepared at various the target bias voltages. RF power, substrate temperature, and deposition time were 400 W, 2000c, and 3 hours, respectively. ZnO:Al thin film prepared at -300 V exhibited the wurtzite structure (α-ZnO), optical absorption edge of 360 nm (3.37 eV) and good optical transparency.
Takumi Namba was received the Bachelar of Engineering degree in electrical engineering from Tokyo University of Science, Tokyo Japan, in 2016. He is now a master course student of Graduate School of Engineering in Tokyo University of Science. His research interest iclude development of oxide compound thin film solar cells as the earth eco-friendly next generation solar cells.