摘要 |
<p>Maskless Coating of Metallurgical Features of a Dielectric Substrate Maskless technique for plating a protective metal layer on existing metallurgical pattern supported on a dielectric substrate by blanket coating said metal layer over said substrate, heating to diffuse the metal into said pattern, and cooling to spall the metal on the non-patterned portions of the substrate surfaces, and mechanically removing the metal layer from the non-patterned substrate surfaces. Optionally, the metal layer can also be blanket coated with a passivating metal film with interdiffusion between them at their interface during the noted heating step. In application to support carries for mounting of semiconductor devices, the substrate will comprise an alumina cased ceramic, the pattern will comprise a molybdenum based metal, and the protective metal layer can comprise a nickel based metal. In this application, the second passivating metal film can comprise gold.</p> |