| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a circuit board capable of reducing transmission loss caused by an open stub formed as a surplus portion of a through-via in the circuit board without sharply increasing a manufacturing cost. <P>SOLUTION: The circuit board is configured such that it comprises a via formed in a through-hole penetrating a substrate and electrically connected with partial wiring layers among a plurality of wiring layers on an inner wall of the through-hole, and a through-via formed in a region surrounding the through-hole on the surface of the substrate and having a pad connected to the via. An opening is formed for preventing the through-via from being connected with a constant voltage wiring layer in a region where the through-hole is formed to ensure penetration. In the circuit board, a capacitor is formed having a pair of electrodes composed of the pad and the constant voltage wiring layer, by employing the constant voltage wiring layer as a nearmost wiring layer, and by more increasing an outer diameter of the pad than the diameter of the opening formed in the constant voltage wiring layer. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
