A method of manufacturing a multi-layer printed wiring board including forming a core substrate, forming a first interlayer insulation layer over the core substrate, forming a first filled via in the first interlayer insulation layer, the first filled via having a bottom portion having a first diameter, forming a second interlayer insulation layer over the first interlayer insulation layer, and forming a second filled via in the second interlayer insulation layer, the second filled via having a bottom portion having a second diameter smaller than the first diameter.