Parallel Gap Welding to Thick-Film Metallization

This study was directed at the parallel gap welding response of a series of gold and platinum-gold thick-film conductor materials which were subjected to various peak temperature/belt speed firing profiles. The parallel gap welding was conducted using a variety of weld voltage/pulse duration settings and a nominal 0.05-mm-thick by 0.38-mm-wide pure gold ribbon. Evaluation of the welds was determined through a 90° peel test. From the resulting data the following conclusions were reached. 1) Parallel gap welding is a viable approach to gold ribbon interconnection to thick film. 2) In general, thicker fired films respond better to parallel gap welding. 3) Sensitivity to firing profile, as reflected by parallel gap weld strength, is a characteristic of each specific thick-film material which must be determined and properly optimized. 4) Sensitivity to weld parameters is a characteristic of each specific material and should be optimized with firing profile. 5) The Pure gold conductor materials are not as satisfactory as platinum-gold conductors for parallel gap welding.