Dielectric block signal filters with cost-effective conductive coatings

摘要

A cost-effective communication filter is prepared by etching the surfaces of a shaped and fired ceramic core, applying an electroless nickel solution to create a nickel layer of limited thickness, electroplating the nickel plated core with a silver layer, patterning the nickel and silver plated core by removing metallization from selected surface areas and then heating the patterned filter block to bond the metal layers. The resulting filters comprise a rigid dielectric core defining a plurality of through-hole passages extending between opposing sides of the core. Present on the core is a pattern of metallized and unmetallized regions wherein the metallized regions of the pattern include an inner layer of nickel and an outer silver-containing layer.