Patent ID: 7852175

Claim:
A circuit board comprising: a wafer of a substantially rigid base substrate, the wafer including a signal-side surface and a ground plane-side surface, the signal-side surface having a pattern of trenches formed thereon that correspond to a planar pattern of transmission line conductors; an intermediate layer of an insulating material on the signal-side and on the ground plane-side of the wafer; a first metal conductor layer on the ground plane-side surface to form a ground plane; a second metal conductor layer on the signal-side surface substantially filling the pattern of trenches to form the planar pattern of transmission line conductors; a substantially flat conformal layer of insulating material that covers the second metal conductor layer on the signal-side surface including the substantially filled pattern of trenches forming the planar pattern of transmission line conductors; and a cover board bonded to the substantially flat conformal layer.