Compound semiconductor device with self-aligned gate and method of producing this compound semiconductor device.

摘要

In a method of producing a compound semiconductor device, a semiconductor layer which makes no alloy with a metal electrode that is to be disposed thereon but makes an ohmic contact with the metal electrode is formed as an uppermost layer in a lamination of epitaxial layers, an ohmic electrode which is easily removed by chemical etching is deposited thereon, a first insulating film is deposited thereon, a groove is formed by chemical etching at a region where a gate is to be formed to expose an active layer, a second insulating film is deposited thereon and etched to form insulating side walls on the internal surface of the groove, and a gate electrode whose shape is regulated by the first insulating film and the side walls is formed. Therefore, the gate electrode and the source electrode are formed self-alignedly with each other, and the interval between the gate electrode and the ohmic electrode is reduced to the width of the side wall, whereby the source resistance is reduced. In addition, since the operation layer, i.e., the uppermost semiconductor layer is not damaged during the formation of the groove, a compound semiconductor device with high performance and high reliability is achieved. <IMAGE>