| 摘要 |
PURPOSE:To obtain a thin film FET having excellent characteristics of an interface between a gate insulating film and a semiconductor layer, by using a lift-off method, by which a minute pattern can be readily formed. CONSTITUTION:An Al gate electrode 8 is formed on a glass insulating substrate 7. A first gate insulating film 9 made of Ta2O5 is deposited thereon, and a photo resist mask 10 having a specified shape is provided. The surface of the insulating film 9 is etched and a hole is provided. A contaminated material 11 is removed. A second gate insulating film 12 made of Al2O3 is deposited on an irregular surface. A CdSe layer 13 is evaporated in a vacuum. Then the resist mask 10 and the insulating film 12 and the semiconductor layer 13 thereon are removed by ultrasonic washing and the like in aceton. Source and drain electrodes 14 and 15 made of Al are evaporated. The device is annealed in an non-oxidizing atmosphere at 300-350 deg.C. Thus the device is completed. In this constitution, the interface between the gate insulating film and the semiconductor layer can be formed cleanly and flatly even if the lift-off method is used. Therefore, the electric characteristics and stability of the thin film FET are strikingly improved. |
