Methods may be provided for forming an electronic device including a substrate, a conductive pad on the substrate, and an insulating layer on the substrate wherein the insulating layer has a via hole therein exposing a portion of the conductive pad. In particular, a conductive structure may be formed on the insulating layer and on the exposed portion of the conductive pad. The conductive structure may include a base layer of titanium-tungsten (TiW) and a conduction layer of at least one of aluminum and/or copper. Moreover, the base layer of the conductive structure may be between the conduction layer and the insulating layer. Related devices are also discussed.