The laser bonder places the ribbon on the desired bond positions and a very sharply focused laser beam writes a specific pattern on the ribbon surface. Thereby a defined melt trough is created with almost vertical walls and very well controlled welding depth into the substrate below the ribbon. This generates a large, defined and programmable bonding interface between ribbon and substrate. The bond loop is then formed as usual, the second bond made like the first and the ribbon or wire is cut. Main advantages are: Bond geometries are highly flexible and freely programmable because the bonder can pull the connecting ribbon in any direction over any distance. The ribbons to be bonded can have cross-sections far larger than possible using ultrasonic bonding, and the surface requirements on the bond pads are less stringent in terms of contamination and mechanical rigidity. The bond forces employed are at least an order of magnitude lower than for ultrasonic bonding. Design rules for the components and operating the bonder are very similar to today‘s wire-bonders.
productronica innovation award: hall B3, booth 428