| 摘要 |
PURPOSE:To easily and rapidly form an insulating board of one or more layer structure without labor and facility cost by providing viaholes or through holes of conductors for connecting between crossing conductor circuits on sections in which the conductor circuits, of the board are stereoscopically crossed. CONSTITUTION:Latticelike conductor circuits 20 of front and rear surfaces of a board 10a are formed in the same size of the same shape, stereoscopically crossed, and stereoscopically superposed. Viaholes 30 are provided at every other one through the board 10a at sections in which the circuits 20 of the front and rear surfaces of the board 10a are stereoscopically crossed, and the circuits 20 are connected at every other ones therebetween by the viaholes 30. Holes 40 are so provided at sections having no viaholes 30 of the sections in which the circuits 20 of the front and rear surfaces of the board 10a are stereoscopically crossed, i.e., at every other ones in the sections in which the circuits 20 are stereoscopically crossed through the board 10a. |
