Patent ID: 9699921
Date: 2017-07-04
CPC Classifications: H01L,H05K

Claim:
1. A multi-layer wiring board comprising: a plurality of wiring bases; and an adhesive layer interposed between the wiring bases, the respective wiring bases including a wiring pattern on at least one surface thereof and a conductive paste via formed therein, wherein the multi-layer wiring board includes an electronic component terminal and a board terminal having terminal pitch different from that of the electronic component terminal, and the multi-layer wiring board has an electronic component installed thereon and connected to the electronic component terminal, wherein the plurality of wiring bases include a first wiring base, a second wiring base, a third wiring base, and a fourth wiring base of similar thicknesses, the second wiring base includes an opening in which the fourth wiring base is housed, and is disposed, along with the fourth wiring base housed in the opening, between the first wiring base and the third wiring base, and the fourth wiring base has a smaller wiring pitch than those of the first wiring base, the second wiring base, and the third wiring base, is built in to between the first wiring base at a lower portion of an installing portion of the electronic component and the third wiring base, is connected to the electronic component terminal via the conductive paste via of the first wiring base, has formed on both surfaces thereof a pattern that enlarges the terminal pitch from the electronic component terminal to the board terminal, and includes a via that connects the pattern of the both surfaces, wherein the fourth wiring base includes first electrodes on one surface thereof facing toward the electronic component and second electrodes on an opposite surface thereof, the respective first electrodes are connected to corresponding one of the second electrodes, and electrode pitch of the first electrodes is smaller than electrode pitch of the second electrodes.