Preparation of polycrystalline SiC films by dry process and their application to thin film transistors

点击翻译按钮获取中文摘要

The summary of this research report is as follows ;1.Preparation of SiC Films : Polycrystalline SiC films were deposited by reactive sputtering. The target was made from a single crystal Si wafer. The reactive gas was CH_4. The substrate temperature must be higher than 700ﾟC to obtain a high quality film. A heater made from carbon ribbon was used to obtain higher substrate temperature than 700ﾟC.2.Characterization of Crystal Structure : Crystal structure of the films was characterized by X-ray diffraction and electron beam diffraction. The sample was polycrystalline when they were deposited at higher temperature than 700ﾟC.The results showed that it was possible by this method to reduce the substrate temperature to 700ﾟC.3.Chemical Properties : XPS measurement showed that the ratio of Si/C was affected not only by the partial pressure of CH_4s but also by the total pressure.4.Electrical Properties : The films were characterized by photo-absorption measurement and Hall measurement. The value of absorption edge was almost the same to the value of 3C-SiC.The results of hall measurement showed that the best quality for the application to TFT was obtained when the films were deposited at 750ﾟC.5.The Control of Conduction Type : Aluminum was more effective than boron as the acceptor impurity to control the conduction type.6.Application to TFT and Other Devices : Thin film transistors, pressure sensors and flow sensors were fabricate using the polycrystalline. SiC films to show its applicability to electronic devices.