| abstract |
An upper substrate having an opening and a circuit formed on the surface layer, an inter-substrate connecting sheet having an opening and a conductive hole filled with a conductive paste in a through hole, and a lower substrate having a circuit formed on the surface layer Are heated and pressed. In particular, the inter-substrate connection sheet is made of a material different from that of the upper substrate and the lower substrate. A multilayer circuit board having an all-layer IVH structure with a cavity structure and high interlayer connection reliability can be manufactured. |