| 摘要 |
PURPOSE:To operate the titled device stably for a prolonged term by coating a GaAs active layer with an Al GaAs protective layer, a high-resistance GaAs protective layer, a source electrode, a drain electrode and a gate electrode and protecting the active layer. CONSTITUTION:An N type GaAs active layer 12 is grown on a GaAs substrate 11. The layer 12 is etched, and currents between a source and a drain are adjusted. An Al GaAs protective layer 14 and a high-resistance GaAs protective layer 15 are grown on the surface of the layer 12. Openings are formed to source-electrode and drain-electrode forming prearranged sections to expose the surfaces of the layer 12, and a source electrode 19S and a drain electrode 19D are formed in the openings. A photo-resist layer 20 is shaped, and an opening 20A is formed on a gate electrode prearranged section. The layer 15 is etched while using the film 20 as a mask to form an opening 15A. When an Al film is shaped and the film 20 is removed, a gate electrode 21G is formed on the surface of the layer 14 through a patterning by a lift-off method. |
