Method of soldering a lead to a sintered lead pad

摘要

A solderable gold conductor composition is formed by dispersing gold and certain inorganic binders in an inert liquid vehicle composition which can be used to produce conductor patterns which patterns adhere to fired ceramic substrates and to which can be soldered leads of electronic components. A method of soldering a copper lead to a lead pad on a substrate. A conductor pattern including at least one lead pad is printed on the substrate using a gold thick film paste composition. The gold composition is composed of finely divided gold particles and finely divided inorganic binder particles dispersed in an inert liquid vehicle, containing by weight 98-99 percent gold particles and complementally 2-1 percent of inorganic binder particles. The binder consists essentially by total weight of gold and binder of 0.6-0.2 percent copper, 0.2 percent lead, 0.2 percent cadmium and the balance being glass. The pattern is then fired to sinter the inorganic materials, and the fired pad is presoldered without the necessity for physically or chemically precleaning the pad prior to soldering. A presoldered copper lead of an electronic component, for example, is then soldered to the presoldered pad.