| 摘要 |
PURPOSE:To form the junction between an operating layer and a gate electrode stably and with good reproducibility, by forming the metal thin film of a high melting point gate on the surface of a semi-insulating substrate, and thereafter forming the operating layer through the metal thin film. CONSTITUTION:A WSi thin film 3a is formed on an semi-insulating GaAs 1. A resist mask 8 is applied. Si ions are implanted and an (n) layer 2 is formed. The resist 8 is removed, and a W gate 3b is formed. Si ions are implanted through the thin film 3a, and an n<+> source and a drain 4 and 5 are formed. Then, with the gate pattern 3b as a mask, the thin film 3a is etched away. SiO2 9 is applied and electrodes 6 and 7 are attached. In this method, contamination of impurities and contamination due to oxidation or resist in the surface of the substrate 1 are conspicuously decreased, a threshold voltage becomes uniform and the junction between the operating layer and the gate electrode can be formed stably with good reproducibility. |
