Abstract: A dual-gate Schottky barrier gate field effect transistor is provided with an intermediate electrode between a first and a second gate electrode. This intermediate electrode forms an ohmic contact with a semiconductor substrate of the transistor. The transistor is produced by etching a first film formed on a planar surface of the substrate by the use of a pair of mask pieces to leave a pair of gate electrodes narrower than the mask pieces and projecting a metal capable of forming an ohmic contact with the semiconductor towards the planar surface perpendicularly thereof. The projected metal provides source and drain electrode on both sides of the gate electrode pair and an intermediate electrode between the gate electrodes. The intermediate electrode may be left floating during operation.