Conduits integrated in circuit board and method of manufacture

Circuit boards (1100, 1400) and methods for fabricating circuit boards that include conduits (1004) are provided. The conduits formed by patterning a metal layer (1102) are lined by inert coating (1106) and caped by a photodefinable polymer layer (1110) that is affixed to the inert coating by with the help of an initially uncured polymer layer (1106). Holes are formed by patterning the photodefinable polymer layer for admitting and removing fluid from the conduit.