Preparation and Characterization of Spin-Coating In-Ga-Zn Oxide Thin-film and its Transistor

• Main Authors: Chin-Huei Chang\, 張景惠
• Other Authors: Hong-Ming Lin
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/46318826413477109812

碩士 === 大同大學 === 材料工程學系(所) === 99 === With the development of 3C industry, LCD flat panel display (FPD) play an important role and the importance are increased year by year. Currently, in the global display market, LCD FDP is one of the most important one in 3C market. In recent years, the awareness of environmental impacts and rising of living standards, 3C products are facing trends in the development of light, thin, short, and small products. So more and more display-related businesses or manufacturers start to focus the research and develop in cost down, and flexible electronic paper. The trivalent element indium, gallium doped into ZnO of In, Ga, Zn oxide (IGZO) become one of the promising material for active layer in TFT. A novel solution-processed preparation for oxide semiconductor layer is investigated in this study. The generally used process of indium gallium zinc oxide (IGZO), metal salts in toxic 2-methoxy ethanol (2ME) in the related research, is successful substituted by this method. In this study, we also change the contents of indium, and the parameters of heat treatment to study the physical and chemical properties of IGZO. TGA used to analysis the physical change of IGZO solution in increasing temperature, XRD to analysis the structure of the thin-film, SPM observed the surface morphology of the IGZO thin-film, UV analysis the transmittance of the thin-film, hall measurement to measure the carrier concentrations and the resistivity, finally, the semiconductor parameter analyzer use to analyze the on/off current ratio, threshold voltage and carrier mobility. In this study, we successfully used n-type IGZO thin-film as an active layer in TFTs. The In:Ga:Zn ratio of 4:1:2, annealed at 500°C for 1hr in the air, the IGZO thin-film exhibit high optical transmittance of 95% in visible range and smooth surface Rms 0.8 nm, the resistivity is 0.86 (Ω -Cm), Ion/off is about 106, filed-effect mobility is 0.63 cm2/Vs, threshold voltage is 4.42V, and subthreshold swing voltage is 1.37 V/dec.