Patent ID: 7973339

Claim:
A diamond semiconductor element having a gate electrode, a source electrode and a drain electrode each formed directly on a diamond single-crystal thin-film at a distance from each other, wherein said source electrode includes a first area close to said diamond single-crystal thin-film and a second area except the first area, where a first distance between a first end face of said first area close to said gate electrode and said gate electrode is less than a second distance between a second end face of said second area close to said gate electrode and said gate electrode, and said drain electrode includes a third area close to said diamond single-crystal thin-film and a fourth area except the third area, where a third distance between a third end face of said third area close to said gate electrode and said gate electrode is less than a fourth distance between a fourth end face of said fourth area close to said gate electrode and said gate electrode, wherein there is no part of the diamond semiconductor element between the first to fourth end faces and the gate electrode, and wherein the first and third end faces of the first and third areas together form an inverted mesa structure.