Method for manufacturing circuit board having conductive via

Abstract

A method for manufacturing a circuit board having a conductive via comprises the steps of providing a substrate having a first surface and a first conductive layer on at least one region of the first surface, forming an insulating layer on the first conductive layer, forming an opening in the insulating layer, so that the opening extending to the first conductive layer, forming a second conductive layer inside the opening and at least on the insulating layer near the opening, applying a positive photoresist on the second conductive layer, exposing the positive photoresist, developing the exposed positive photoresist, and removing the positive photoresist on the second conductive layer, except a portion of the second conductive layer that is inside the opening, etching the second conductive layer, to expose a surface of the second conductive layer, removing the positive photoresist from inside the opening, and forming a third conductive layer inside the opening.

Dependencies are inferred from the claim text.