Patent ID: 8890001
Filing Date: 2014-11-18
Classification: H01L,H05K

Abstract:
1. A wiring board comprising: a substrate including a woven fabric formed of a plurality of glass fibers and a resin covering the woven fabric; a plurality of through holes penetrating through the substrate in a thickness direction thereof; and a plurality of through hole conductors adhered to inner walls of the through holes respectively, wherein the through holes comprise a first through hole and a second through hole, in the woven fabric, the number of the glass fibers through which the first through hole penetrates is larger than the number of the glass fibers through which the second through hole penetrates, in the first through hole and the second through hole, narrow width portions thereof having narrowest widths, respectively, are surrounded by the woven fabric, and the narrow width portion of the first through hole is smaller than the narrow width portion of the second through hole.