Circuit substrate, detector, and method of manufacturing the same

摘要

A cylindrical, electrical insulating region is formed in a circuit substrate made of a semiconductor substrate to continuously extend from the upper surface to the lower surface of the semiconductor substrate and be closed in a plane parallel to the surface of the semiconductor substrate. The electrical insulating region is formed by an insulating region made of a heat-resistant insulating material. The insulating region is formed by forming a through hole or trench in the circuit substrate and forming an oxide film or nitride film on the wall surface of the hole or trench or filling it with an insulating material. When the trench is formed, the substrate is thinned by polishing or the like until the trench appears on the upper and lower surfaces of the substrate after the insulating region is formed. The region surrounded by the insulating region functions as an electrode when the conductivity of the region is increased by diffusing an impurity in it.