SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing technique which can prevent field concentration at a bottom of a trench gate and which is unlikely to cause a problem due to a layer structure such as a stage cut of an electrode and a decrease in withstand voltage.SOLUTION: A manufacturing method of a semiconductor device 1 by a gallium nitride semiconductor comprises the following processes: (a) a process of forming irregularities 30 on a surface of a first n-type semiconductor layer 20 provided on a substrate 10 of an n-type semiconductor on the side opposite to the substrate 10; (b) a process of forming a p-type semiconductor layer 40 which functions as a channel layer of the semiconductor device 1 on the first n-type semiconductor layer where the irregularities 30 are formed on the side opposite to the substrate 10; (c) a process of reducing a thickness of the p-type semiconductor layer 40 by etching the p-type semiconductor layer 40; and (d) a process of forming a second n-type semiconductor layer 50 on the etched p-type semiconductor layer 40 on the side opposite to the first n-type semiconductor layer 20.