Patent ID: 8587092

Claim:
A semiconductor device comprising: a compound semiconductor region; and a protective insulation film covering at least part of a surface of the compound semiconductor region and being formed so as to contact with at least part of the compound semiconductor region, wherein the protective insulation film comprises a two-layer structure constituted by a first insulation film composed of first insulation material formed into a state that a degree of chemical activity to the surface of the compound semiconductor region is high, and a second insulation film stacked on the first insulation film and composed of second insulation material having a lower chemical activity degree than the first insulation film, wherein the first insulation film composed of the first insulation material contacts with at least part of the compound semiconductor region directly; and wherein the first insulation film is a silicon nitride film and includes 1.0×10 22 /cm 3 or more Si—H bonds, or the first insulation film is a silicon nitride film and includes 1.0×10 22 /cm 3 or more N—H bonds.