| 摘要 |
PURPOSE:To enable to form finely thin patterns by a method wherein the first grade thin pattern is formed within a recess formed by etching process and then the second grade thin pattern is formed. CONSTITUTION:Resist pattern 43 to form ohmic metal pattern are formed on the surface of an active layer 42 formed on a semi-insulating GaAs substrate 41. At this time, before coating the active layer 42 with an ohmic metal, the active layer 42 is etched utilizing the resist pattern 43 as mask making the etching depth similar to the metal thickness. Later the surface of GaAs substrate may be flattened by means of coating it with ohmic metal 44 and lifting off the same. The surface is heat-treated to come into ohmic contact with the active layer 42. Next a Schottky gate metallic pattern is formed in a region 45 between the ohmic metals on the surface of the active layer 42. An opening 47 to form a minute gate may be formed with excellent precision since resist 46 to form patterns may be coated with even thickness due to flattened surface of GaAs. |
