Surface preparation of ceramic substrates for metallization

摘要

A process for preparing a ceramic substrate for metallization wherein a surface of the ceramic substrate is contacted with a composition containing one or more alkali metal compounds, preferably in the form of solid pellets. The pellets are melted on the ceramic surface. As the pellets melt, advancing waves of the molten composition spread across and wet the ceramic surface. The molten alkali metal composition is kept in contact with the ceramic surface for a time period sufficient to etch the surface and thus prepare it for adherent deposition of metal. The moving waves of melting composition supply fresh alkali metal compounds at the ceramic surface. After adhesion promotion, the ceramic surface is treated with compounds that promote adsorption of catalyst for metal deposition before being plated with metal. Uniform surface coverage with catalyst and metal and an improved adherent bond of metal to the ceramic surface are obtained. Furthermore, an article comprised of metal directly and adherently bonded onto a ceramic substrate is provided, the bond strength exceeding about 25 MPa.