Compound semiconductor device having overhang-shaped gate

摘要

A compound semiconductor device includes: a compound semiconductor layer; a protective insulating film that covers a top of the compound semiconductor layer; and a gate electrode formed on the protective insulating film, wherein the protective insulating film has a first trench and a second trench which is formed side by side with the first trench and in which the protective insulating film remains with only a predetermined thickness on the compound semiconductor layer, and wherein the gate electrode fills the first trench, and one end of the gate electrode is away from the first trench and located at least in the second trench.

主权项

1. A compound semiconductor device, comprising:
a compound semiconductor layer; a protective insulating film that covers a top of the compound semiconductor layer; and a gate electrode in which a first portion at a lower part and a second portion being wider than the first portion at an upper part are integrally formed, and a lower surface of the first portion is formed on the protective insulating film or on the compound semiconductor layer, wherein the protective insulating film has a first trench and a non-through second trench which is formed side by side with the first trench, and wherein the first portion of the gate electrode fills the first trench, the second portion covers a part of an upper surface of the protective insulating film, and one end of the second portion is away from the first trench and located at least in the second trench.