| 摘要 |
A wiring substrate (A) includes an insulating substrate (1) and a wiring conductor (2) attached to the upper and the lower side of the insulating substrate (1). The wiring conductor (2) includes a different tracks (6) consisting of two band-shaped conductors which are attached to the upper side of the insulating substrate (1) and are arranged in parallel. The insulating substrate (1) comprises a glass cloth (6) which is vertically woven with a bundle of glass fiber and has a gap in it and a recess on a surface, and a flat insulating resin part (5) which is filled in the gap and the recess and is formed on the upper and the lower surface of the glass cloth (4). A difference between the relative permittivity of the glass cloth (4) and the relative permittivity of the insulating resin part (5) is 0.5 or less. |
