Focus on Flip Chips


Don’t you just love being right? It took a long time for flip chips to go mainstream, but now that they have made it, it’s very satisfying.

One look at the year so far indicates positive growth in packaging applications. Just look at the increase in flip chip shipments. Sales are up for PCs, chipsets, and CPUs. ASIC designs have incorporated flip chip. When graphics chips used in gaming applications shifted from wire bond to flip chip at the end of last year, the whole picture changed. The demand for flip chip substrates is also increasing. Organic laminate - a less-expensive substrate material - is growing with a value of more than $4.2 billion, according to some analysts. The growth of flip chip accounts for this boom.

Recent articles in Advanced Packaging covered the C4NP wafer-bumping process for molding flip chips, which was invented by IBM and is now being tested by them on equipment provided by SUSS MicroTec. This method has not entered the commercial market as of yet, but is still in testing at IBM in Fishkill, NY. As the flip chip area grows, there will be a need for a less-expensive way to make flip chips as well. Timing is everything. The obvious next step is for C4NP to travel to China as these two trends come together like droplets of water following the same path.

China, after all, is predicted to be the largest IC-consuming country in the world by 2010. “China’s government policy to develop the semiconductor industry, and the general trend of the world’s IC manufacturing industry moving into China, are driving China as a prime location for IC design and manufacturing,” says Anty Zheng, analyst at In-Stat. As sure as our children will teach us how to apply electronics, is how certain I feel that any new technology for producing flip chips in a cheaper mode will go mainstream there.

Therefore, when our magazine editors decided to start a Roadshow blitz, visiting packaging companies to experience an “in-the-trenches” view of the industry, our first stop was at SUSS MicroTec in Waterbury, VT, to follow up on the progress of the C4NP project with IBM, as featured in our November 2005 cover story. Our next stop was to visit John Harris, manager of worldwide test engineering at IBM Microelectronics in nearby Burlington, VT, for a tour of the engineering test center to find out what’s new in sockets. You can read about the Roadshow debut at Or turn to pages 8 and 9 to experience this insightful trip through photos. More road trips are in the works, so visit our website to submit your reasons why we should visit your company and spend some time in your environment.

What did our first road trip teach us about the world of flip chips and package testing? We learned enough to know that testing is essential for reliability. We learned enough to share the stage that C4NP is at now, and to predict where it will develop as part of the “smaller, faster, cheaper” saga of our industry. From our firsthand experience and vantage point, flip chips are healthy.

Click here to enlarge image

Gail Flower