E! 7083 Polymer Core Solder Balls (PCSB) for High Reliability Volume Electronics Manufacturing

Ball Grid Array teknologi har vært i bruk i elektronikkindustrien i mer en 20 år. Men økede krav til pålitelighet samt utfasing av bly i loddetinn har skapt store utfordringer for teknologien. Dette bunner hovedsaklig i at tradisjonelle SnAgCu loddekuler er veldig utsatt for utmattingsbrudd. I gjennom dette prosjektet ønsker Conpart å utvikle og introdusere en ny familie med loddekuler, basert på polymerkjerne teknologi. Ved å benytte en fleksibel polymerkjerne vil belastningen reduseres og dermed også problemet med utmatting. Dette vil kunne øke påliteligheten, og dermed levetiden til produktenen som benytter den nye typen loddekuler med polymerkjerne.

Through this project, Conpart aims to be the first company able to provide Polymer Core Solder Balls with a significantly better reliability and at a cost comparable with traditional solder balls. The balls from the present supplier, Sekisui, is presently far to expensive to have a major market share. Combining high reliability, high assembly yield and low cost is a major undertaking, but we believe that the present consortium have the technology, competence and capabilities to do so. There are a number of innovative elements in this project, going beyond present leading edge technology. The first element is related to the polymer core. In the PCSB project we introduce a new manufacturing technology for making this critical element. The process is based the well known Ugelstad technology and for this particular application we utilises condensation polymers. In collaboration with Sintef and Microbeads we will explore the mechanical and thermo-mechanical properties of different monomer combinations and pro cess parameters. The next innovative element is to minimise the size distribution of the polymer balls as produced in the polymerisation reactor. Traditionally the coefficient of variation (CV) after polymerisation has been much more than 10 %, which req uires a costly mechanical classification technique. Our unique polymerisation process yields a uniquely narrow size distribution, and by optimising the processes even further we believe we can reduce the CV to less than 1,5%, which radically reduces the n eed for size classification. The third innovative element is related to the metal plating of the polymer core. In this project we will transfer the patented pulse-plating technology developed for panel plating into barrel plating of small spheres. The technique which is invented by Polymer Kompositer significantly improves the homogeneity and uniformity of the plated metal, which is even more critical for the barrel plating.