| 摘要 |
PURPOSE:To increase an output by holding an active layer consisting of an N type conpound semiconductor by insulating compound semiconductor layers having electron affinity smaller than the active layer and forming a Schottky gate electrode on one insulating compound semiconductor layer. CONSTITUTION:An I-type AlxGa1-xAs layer 22, an N type GaAs active layer 23 and an I-type Alx1-xAs layer 24 are grown continuously on a semi-insulating GaAs substrate 21. Selenium is introduced to regions to which a source and a drain are formed, and an N<+> type source region 25 and a drain region 26 are shaped through heat treatment. Elements are isolated, and high resistance regions 27 are formed. Electrodes 28 and 29 being in ohmic-contact with the N<+> type source region 25 and drain region 26 are disposed, and a gate electrode 30 being in Schottky-contact with the I-type AlGaAs layer 24 is arranged. A surface protective film 31 is shaped by silicon dioxide, silicon nitride, etc., openings are bored and gold (Au) layers 32 are formed for connecting wirings. Accordingly, gate length is shortened, excellent characteristics are ensured, and a high output can be obtained in an ultrahigh frequency zone. |
