PURPOSE: To realize a MIC amplifier circuit with a small noise figure and a large 1dB compression output voltage and an IM3 intercept point and a high gain by means of a comparatively simple process.

CONSTITUTION: A fist stage amplifier or plural amplifiers having the 1st and succeeding stage amplifiers except the final stage amplifier are formed by using FETs 11, 12 having a gate of self-alignment structure. Then as FETs 13, 14, FETs in which a gate electrode 8 is formed so that an end of a source is overlapped on a source high impurity concentration region via an insulation film on an operating layer 2 inserted between the source and a drain high impurity concentration region 4 and the drain end does not reach the said drain high impurity concentration region 4.