Patent ID: 7730613

Claim:
A method of constructing a printed wiring board including an electrically conductive constraining core, where the electrically conductive constraining core is a functional layer of the printed wiring board, and where the printed wiring board includes at least one additional functional layer using a single lamination cycle, comprising: drilling a pattern of clearance holes in an electrically conductive constraining core; arranging the electrically conductive constraining core in a stack up that includes B-stage [semi-cured] layers of dielectric material on either side of the constraining core and additional layers of material, where the electrically conductive constraining core, the B-stage [semi-cured] layers of dielectric material, and additional layers of material are arranged so that lamination of the stack up forms the functional layers of the finished printed wiring board; performing a lamination cycle on the stack up that causes the resin in the B-stage [semi-cured] layers of dielectric to reflow and fill the pattern of clearance holes in the electrically conductive constraining core before curing; and drilling through holes through the laminated stack up and plating the through holes to create at least one electrical connection between the electrically conductive constraining core and one of the at least one additional functional layers.