Method of manufacturing a semiconductor device having a group-III nitride superlattice layer on a silicon substrate

A method of manufacturing a semiconductor device, including the steps of:

• (1) blowing a hydrocarbon gas onto a surface of a silicon single crystal substrate and thereby causing hydrocarbon to be adsorbed onto the surface of the substrate;
• (2) heating the silicon single crystal substrate to a temperature of not less than a temperature at which the hydrocarbon is caused to be adsorbed, thereby forming, on the surface of the silicon single crystal substrate, a cubic silicon carbide layer whose lattice constant exceeds 0.436 nm and is not more than 0.460 nm and which has a nonstoichiometric composition containing silicon abundantly in terms of composition;
• (3) supplying a gas containing a Group V element and a gas containing Group III element to the surface of the silicon carbide layer and thereby forming a Group III nitride semiconductor junction layer;
• and
• (4) forming a superlattice-structured layer constituted by Group III nitride semiconductors on the Group III nitride semiconductor junction layer.