| 摘要 |
PURPOSE:To reduce the distance between each electrode by a method wherein side etching is performed on the lower layer of a double gate metallic layer with the upper layer thereof as a mask, and after providing photoresist on the side surface thereof, metal for a source and drain is evaporated. CONSTITUTION:A high resistant GaAs layer 2 and mesa type GaAs operating layer 3 are formed on a semi-insulating GaAs substrate 1. Thereafter, Al layer 21, Ti layer 22 and SiO2 film are laminated to form a gate electrode by means of a photoresist pattern. Then, an Al lower layer 21a is side-etched with the Ti upper layer 22a as a mask, and AuGe/Ni for ohmic electrode is evaporated over the whole surface under a state of the photoresist provided on the side surface of the layer 21a to form source and drain electrodes 27a, 27b by a lift-off method utilizing an SiO2 film and a photoresist. Thus, source and drain resistances are reduced to improve the characteristic of the FET. |
