| 摘要 |
PROBLEM TO BE SOLVED: To allow normal operation of an electronic component such as a semiconductor element for an extended period by allowing formation of a signal line, a power source line, a ground line in high density, while intrusion of noise into the signal line is effectively prevented. SOLUTION: A wiring board 1 comprises a plurality of organic resin insulating layers 3b in multiple layers, with an organic resin insulating body 3 comprising a mounting part 3a where an electronic part 7 is mounted on its surface and signal line, a power-source line 5, and a ground line 6, which being allocated among the organic resin insulating layers 3b, are formed by thin-film formation technology in which a signal electrode, a power-source electrode, and a ground electrode of the electronic part 7 are provided electrically connecting. Here, at least one auxiliary ground line 6a branches off the ground line 6, the signal line 4 is sandwiched between, above and below, the ground line 6 and the auxiliary ground line 6a, and at least a part of the ground line 6 and/or the auxiliary ground line 6a contains magnetic powder, forming a magnetic region. |
