A package substrate includes; a conductive line extending in a first horizontal direction, a conductive pad on an upper surface of the package substrate and horizontally spaced apart from the conductive line in a second horizontal direction, and a protective layer covering the conductive line and including an opening selectively exposing a portion of the conductive pad. The opening has an elongated elliptical shape having a minor axis defined by a width extending in the first horizontal direction and a major axis defined by a length extending in the second horizontal direction.