Patent ID: 8084695

Claim:
A via structure in a circuit board or substrate having multiple layers, from top to bottom comprising: a first power plane or a first ground plane in the first layer; a first medium in a second layer; a first signal trace in a third layer; a second medium in a fourth layer; a second signal trace in a fifth layer; a third medium in a sixth layer; a second power plane or a second ground plane in a seventh layer; a power via or a ground via passing through the first medium, the first signal trace, the second medium, the second signal trace, and the third medium, wherein the first power plane or the first ground plane is connected with the second power plane or the second ground plane through the power via or the ground via; a signal via passing through the second medium around the power via, and the first signal trace is connected with the second signal trace through the signal via; and an anti-pad is located between the signal via and the power via or a ground via, wherein the power via or the ground via is cylindrical and the thickness of the power via or the ground via is larger than the skin depth at the frequency of the signal; and when a signal going through a path from the first signal trace through the signal via to the second signal trace, the signal goes through the path with complete impedance continuity.