Electroless NickeVImmersion Gold Finishes - 2 for Application to Surface Mount Technology : ~ - A Regenerative Approach
نویسنده
چکیده
ine pitch surfact mount technology (SMT) devices are forcing F the industry to look for alternatives to the traditional hot-air solder leveling (HASL) process. Although HASL gives an excellent surface for solderability it has its shortcomings. HASL finishes are not flat (see Fig. I), they contain lead, are not aluminum or gold wire-bondable and the resulting board has already undergone a thermal excursion, which can only have adverse effects on product effective life performance. Fine pitch work requires a flat coplanar surface for the precise application of solder paste in reflow and for ball grid array (BGA) assembly. Ultrafine pitch devices may require a wire bondable as well as a solderable surface. Electroless nickell immersion gold surface finishes meet the demands of the evolving technology trends of today.
منابع مشابه
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