| 摘要 |
PURPOSE:To reduce the characteristic change of an active region as large as possible by forming an interlayer insulating film in 2-layer structure having the first insulating film made of a thin deposited insulating film due to resistance heating and the second insulating film which is sufficiently thick due to a plasma CVD method. CONSTITUTION:Electrodes 1, 2, 4 are formed on a semi-insulating GaAs substrate, the first insulating film 5a made of thin silicon oxidized film due to resistance heating deposition is accumulated, and the second insulating film 5b made of sufficiently thick silicon nitrided film is accumulated by plasma CVD method on the entire surface. Further, a photoresist layer 7 is covered and a window 8 is patterned thereon by the normal photolithography the film 5 of 2-layer structure is selectively etched, opened at a hole 9, and wiring metal 6 is formed on the second insulating film 5b. |
