Circuit board and manufacturing method of circuit board

Abstract

A circuit board includes a first insulating layer and a lower pad exposed from the first insulating layer, with the exposed surface recessed below the surface of the first insulating layer. A second insulating layer is formed on the first insulating layer, and an upper pad is disposed on the second insulating layer. A via penetrates the second insulating layer and electrically connects the lower pad and the upper pad. A plating layer, such as a nickel and gold layer, is disposed on the upper pad. The circuit board structure may enable reliable electroplating without requiring a separate bus line by utilizing a seed copper layer from a detachable core.

Dependencies are inferred from the claim text.