Patent ID: 8726495

Claim:
A manufacturing method of a multi-layer board comprising: forming at least one internal layer base material comprising a first insulating layer, a first conductive circuitry with a first land only at a first surface of the first insulating layer and a first interlayer conductive portion which contacts with the first land for electrically connecting the first conductive circuitry and a second surface of the first insulating layer thereof; forming a base material comprising a second insulating layer, a second conductive circuitry with a second land at a first surface of the second insulating layer, a third conductive circuitry at a second surface of the second insulating layer, and a second interlayer conductive portion which contacts with the second land and a third land to electrically connect the second conductive circuitry and third conductive circuitry; and colaminating the internal layer base material and the base material so that the third conductive circuitry of the base material and the first conductive circuitry of the internal layer base material are electrically connected to one another by the first interlayer conductive portion via the first and third lands, wherein the second land is formed smaller in diameter than the third land, the second conductive circuitry is finer in width and pitch than the first and third conductive circuitries, the third land is formed larger in diameter than the first interlayer conductive portion to set an accuracy in positioning of the internal layer base material and the base material within a tolerance in the colaminating thereof.