| 摘要 |
PROBLEM TO BE SOLVED: To realize a multilayer printed board of a structure that the thickness of the multilayer printed board formed by alternately arranging wiring layers and insulating layers is uniformly formed and at the same time, an impedance in the printed board is easily controlled at a prescribed value, and to realize the manufacturing method of the multilayer printed board. SOLUTION: When insulating layers are formed, beads 35 of the same thickness as that of the insulating layers subsequent to the formation of the insulating layers 34 are scattered in the layers 34 to constitute a multilayer printed board, whereby an irregularity in the distribution of the printed board thickness is suppressed and the permittivity of the board is controlled by selecting the size of the beads 35 and the material for the beads 35. As a result, as the irregularity in the distribution of the printed board thickness can be lessened and at the same time the permittivity of the printed board can be changed, an impedance in the printed board can be easily controlled. |
