VAPOURPHASE VACUUM-SOLDERING: A NEW PROCESS TECHNOLOGY OPENS TREMENDOUS PRODUCTION CAPABILITIES WHEN REFLOW-SOLDERING

摘要

A new machine technology combines a latest generationrnvapour-phase soldering machine - as optimal heat-transferrnmedium - with classical vacuum-technology. Thus it isrnnow possible to solder absolutely void-free even areas asrnlarge as cigarette packages. Solder alloys with or withoutrnlead may be used with this new technology.rnThe problem of voids in solder joints is known since thernbeginning of the soldering technology. For the majority ofrnsoldering applications this was not a serious handicap, inrnsome instances is actually considered helpful. However,rnwith increasing integration density, the changing shape ofrnthe components as well as other demand profiles andrnapplication requirements of the electronic assemblies andrntheir respective mechanical joints, there is an increasingrndemand for void-free solder joints. Until recently onlyrnsmall batches of such product could be processed inrnspecial vacuum ovens. There the solder product is heatedrneither through conduction or radiation. Oxide-freernsoldering was only possible by applying multiple rinsingsrnwith a forming-gas. Due to the extremely long processrntimes and a most complex process only small quantitiesrnmay be soldered. Due to large process overheads andrnmany rejects the cost for the end-product is very high.