Patent ID: 8508046

Claim:
A circuit substrate, comprising: a substrate containing silicon and comprising an internal terminal electrode containing metal; a wiring layer containing metal chosen from group of Cu, Al, Ti, and Ni that is formed on a portion of a surface of the substrate and is electrically coupled to the internal terminal electrode; an insulating film that covers a second portion of the surface of the wiring layer while not covering a first portion of a surface of the wiring layer; and an external terminal electrode containing metal and electrically couple the internal terminal electrode to the exterior by covering the first portion of the wiring layer and electrically coupling to the wiring layer; wherein the second portion of the wiring layer includes an edge portion viewed from the direction perpendicular to the surface of the substrate; wherein the angle of the cross-section of the wiring layer taken perpendicularly to the surface of the substrate in the edge portion contacting with the substrate is 55° (55 degree) or less; and wherein the wiring layer that comprises a plurality of mutually independent columnar crystals extending in a direction different from the direction of the surface of the substrate.