Solder bumping through Super Solder

Abstract

Flip chip mounting technology is currently being considered for use in consumer information equipment, and industry is waiting for the establishment of solder bump forming technology as an essential constituent of flip chip (FC) mounting technology. At the present, however, no bump forming technology offers a combination of simple process and low cost. Furukawa Electric has developed a lattice substitution solder generation technique (Super Solder, or SS) to supply solder to the pads on PC boards. Taking advantage of the unique characteristics of the SS technique, the authors have developed a solder bump formation technology for FC, under the key concepts of simple process, low cost and non-bridging solder supply. The technique has proven successful in forming solder bumps with ample volume for practical application.