PURPOSE: To reduce source resistance, and to minimize a noise index by determining a distance between a source electrode and a drain electrode by a first insulating film and gate length by a window hole in a second insulating film and forming a recessed section in a gate section through selective etching while using the second insulating film as a mask.

CONSTITUTION: A high-resistance buffer layer 2 and a first conduction type layer 3 are formed on a semi-insulating GaAs substrate 1, and an insulating film 11 is etched selectively while the film 11 is left only by a distance l between a source and a drain and a photo-resist layer 12 is used as a mask. A source electrode 13S and a drain electrode 13D are formed. The photo-resist layer 12 and a metal 13 are lifted off. A silicon nitride film 14 and a photo-resist layer 15 are applied, and a window hole 16 determining gate length is formed at a central section. A window hole 14a is shaped, a recessed section 6 in a gate section is formed through selective etching, and the source electrode 13S and the drain electrode 13D are positioned at the end edge of the recessed section. A gate metal 17 is applied only to a section corresponding to the window hole 14a.