Patent ID: 8153906

Claim:
A via structure in an interconnection structure for switching signals between circuit boards, from top to bottom comprising: a first power or ground layer in a first layer; a first medium in a second layer; a first signal layer in a third layer; a second medium in a fourth layer; a second signal layer in a fifth layer; a third medium in a sixth layer; a second power or ground layer in a seventh layer; a power or ground via passing through the first medium, the first signal layer, the second medium, the second signal layer and the third medium, and connecting the first power or ground layer to the second power or ground layer; a signal via passing through the second medium around the power or ground via, and connecting the first signal layer to the second signal layer; an anti-pad being located between the power or ground via and the signal via; wherein when the signals propagating through a path from the first signal layer through the signal via to the second signal layer in the interconnection structure, the signals propagate through the path with complete impedance continuity.