FIELD EFFECT COMPOUND SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To allow a cross-sectional shape of a gate electrode to be a precise step shape having a left-right symmetrical structure containing a smooth tapered side wall, relating to a field effect compound semiconductor device and its manufacturing method.SOLUTION: On a lamination structure containing a gallium nitride based channel layer/gallium nitride based carrier supply layer provided on a substrate, a multilayer structure film is provided which is made from two or more layers of an insulating film having difference in composition or density from each other, to form a gate opening part having a shape of left-right symmetrical structure that contains a step according to the number of layers of multilayer structure film.