A semiconductor device may be provided with: a semiconductor chip; an encapsulant encapsulating the semiconductor chip therein; and a conductor member joined to the semiconductor chip via a solder layer within the encapsulant. The conductor member may comprise a joint surface in contact with the solder layer and a side surface extending from a peripheral edge of the joint surface. The side surface may comprise an unroughened area and a roughened area that is greater in surface roughness than the unroughened area. The unroughened area may be located adjacent to the peripheral edge of the joint surface.