PROCEDE DE DORAGE SANS COURANT

摘要

Electroless gold plating of thin tungsten or molybedenum metallisations on ceramic bodies is carried out by (a) contacting the metallisation surfaces with an aq. HF/H2SiF6 soln., followed by an aq. alkaline bath of pH at least 10 and then an aq. acidic bath of pH max. 3; and (b) gold plating the treated surfaces in an aq. gold-contg. bath. USE/ADVANTAGE - The process is esp. useful in prodn. of electronic ceramic components such as ceramic substrates and housings for ICs. An adherent electroless gold layer is provided on tungsten or molybdenum layers which have been fired onto ceramics esp. using silicate-contg. metallisation pastes.