Field effect transistor and manufacturing method thereof

摘要

A dummy gate is removed together with an SiO2 film thereon by lift-off to form a reverse dummy-gate pattern with the SiO2 film. A photoresist pattern is formed to cover the reverse dummy-gate pattern and an SiN protection film therebetween, and a mesa pattern is formed by mesa etching. The photoresist pattern is etched so that the edge of the photoresist pattern is located between the edge of the mesa pattern and the edge of the reverse dummy-gate pattern and the exposed part of the SiN protection film is etched. The edge of the SiN protection film is thus located inside the edge of the mesa pattern.