05/20/2011, Irvine, California


Silver Price Control: New Materials Technology Helps Mitigate Silver’s Rising Cost

With the relentless rise in silver prices over the past couple of years has come a packaging production cost challenge for device manufacturers: how to manage the faster, better, cheaper demands of consumers alongside such a challenging market factor.

Silver is a critical metal in electronics production – particularly for the packaging sector in which conductive die attach pastes are filled with the precious metal to deliver necessary thermal and electrical conductivity. In 2009, the average cost (yearly) for silver was approximately $15 per troy ounce. Just two short years later, silver sits at over $35 per troy ounce. This sharp increase in price has placed severe cost pressures on packaging specialists as they try to manage the financial impact while also dealing with the unpredictability of the situation.

While silver’s price peak is anyone’s guess, there is a solution that may help to ease a bit of the pressure and offer some silver price control (SPC). The acronym SPC used to abbreviate Silver Price Control (as well as Statistical Process Control and a host of other terms) is also an abbreviation for the silver cost remedy: Silver Plated Copper. Though the concept of silver plated copper technology isn’t new, its application is only really now just coming into its own as production and coating techniques have dramatically improved in recent years. The name is as it suggests – tiny particles of copper are coated with silver, producing SPC filler that can provide similar electrical and thermal performance to that of silver flake when used with advanced materials formulation techniques. The silver coated particles themselves are tricky to design, but modern processes have now delivered high quality silver plated copper and the metal combination is already being used with several die attach pastes.

Because significantly less silver is used with SPC as compared to pure silver flake, Henkel has been able to leverage the new metal technology to develop die attach adhesives that offer excellent performance but at a lower cost than traditional silver‐filled materials. However, it’s not just about the SPC. Formulation of advanced die attach pastes using SPC takes exceptional materials science expertise, as ensuring rheology control and system stability is much more challenging than with traditional die attach adhesives. But, with Henkel’s innovative team and depth of resource, we have been able to not only deliver more cost‐conscious die attach alternatives, but materials that offer outstanding performance. The Ablestik‐brand SPC die attach pastes have been proven to deliver similar or better thermal and electrical performance to that of silver‐filled alternatives, while providing better dispensability, zero bleed and MSL1 capability.

Currently, there are two Henkel SPC‐based die attach adhesives that are being used in production. Many more are in development and we anticipate market availability of this suite of SPC products over the next six to 12 months. For packaging firms that are ready to make a switch now – and improve forward‐looking cost visibility in the process – Henkel offers two SPC die attach formulations. The first, Ablestik 3230A, is an SPCbased die attach adhesive for copper leadframe packages and has been proven over many years with customers that produce QFPs, QFNs and SO devices. The material has excellent open time performance, provides good reliability, is very low voiding and enables good filleting. Developed for use with large BGA applications, Ablestik ABLEBOND 2310 delivers good dispensing capability and has excellent reliability across a variety of die sizes up to die as large as 13mm x 15mm. With a work life of greater than 24 hours, Ablestik ABLEBOND 2310 also offers excellent process flexibility.

Henkel has effectively combined SPC technology with the company’s formulation expertise to yield new die attach materials that provide many benefits for today’s packaging specialists. Top among the advantages is the lower cost of the materials as compared to silver‐filled equivalents and, therefore, better long‐term cost stability. This, in combination with the outstanding performance and excellent processability of the materials, provides a more cost‐sensitive solution without sacrifice.

For more details on Henkel’s latest SPC (Silver Price Control via Silver Plated Copper) innovations, log onto www.henkel.com/electronics or call 714‐368‐8000.