Patent ID: 8026486

Claim:
A radiation detector, comprising: an Al 2 O 3 substrate; a Fe 2 O 3 thin film layered on the Al 2 O 3 substrate; a Ca x CoO 2 (where 0.15<x<0.55) thin film that is layered on the Fe 2 O 3 thin film and that has CoO 2 planes that are aligned inclined to the surface of the Al 2 O 3 substrate, the surface of the Al 2 O 3 a substrate being an r plane, an n plane, or an S plane; a first electrode disposed on the Ca x CoO 2 thin film; and a second electrode disposed on the Ca x CoO 2 thin film in a position opposed to the first electrode in the direction in which the CoO 2 planes are aligned inclined.