A method and apparatus to eliminate conductive contamination reliability problems for assembled substrates, such as electrical arcing in power semiconductor leads. One embodiment of the invention involves a method for assembling an electrical component having leads on a substrate having conductive contacts, wherein an elastomer part encapsulates the leads of the electrical component. A second embodiment of the invention involves assembling an electrical component having leads to a substrate having conductive contacts, wherein an elastomer shape cut by a punch die encapsulates the leads of the electrical component. A third embodiment of the invention involves an assembled substrate including an electrical component having leads, and an elastomer surrounding the leads to encapsulate the leads.