Patent ID: 8895871

Claim:
A circuit board being a High-Density-Interconnect HDI circuit board comprising a plurality of circuit board layers arranged one over the other, characterized in that the circuit board layers each comprise an electrically insulating base material comprising a glass fiber reinforced plastic with an incorporated filler material, the glass transition temperature of which base material being greater than or equal to 170° C., and that the circuit board layers each have at least one thermally conductive layer applied to the electrically insulating base material, wherein several vias extending in a z-direction perpendicularly to the circuit board layers are provided, which vias connect the thermally conductive layers of different circuit board layers in such a way that the vias and the thermally conductive layers of the circuit board layers form a thermally conductive bridge from a topmost circuit board layer to a bottommost circuit board layer, wherein a total surface area of all the at least one thermally conductive layer of a selected circuit board layer is larger than a total surface area of all the at least one thermally conductive layer of another circuit board layer above the selected circuit board layer.