Abstract: A method of manufacturing a semiconductor device includes forming a first AlN layer on a first main surface of a single-crystal substrate, partly etching the first AlN layer to form a plurality of pieces of AlN seed crystals on the first main surface from the first AlN layer, and forming a second AlN layer on the first main surface using the AlN seed crystals as growth nuclei.

Abstract: A method for manufacturing an epitaxial substrate includes the steps of: epitaxially growing a group III nitride semiconductor layer on a substrate; removing the substrate from a growth furnace; irradiating a surface of the group III nitride semiconductor layer with ultraviolet light while exposing the surface to an atmosphere containing oxygen; and measuring a sheet resistance value of the group III nitride semiconductor layer.

Abstract: A method of manufacturing a semiconductor device, includes attaching a first susceptor to a film forming apparatus, measuring a magnitude of a warp of the first susceptor, setting a first initial film formation condition as a film formation condition of the film forming apparatus in accordance with the measured magnitude of the warp of the first susceptor, and placing a plurality of first wafers on the first susceptor and forming a first film on the plurality of first wafers under the film formation condition. The setting of the first initial film formation condition includes reading the first initial film formation condition from a recording medium storing a database. The database includes a plurality of pieces of data in which magnitudes of warps of susceptors are associated with initial film formation conditions for forming the first film.