You Said It

02/01/2004

In the period of time between the end of winter holidays and the buildup to spring activities, readers become a little more social. They're happy to show off their latest projects or talk about the future of advanced packaging as they see it. I find this one of the most enjoyable times to be an editor.

One of the reasons that the back-end is leading the recovery is that advances in substrate and material development have accelerated the adoption of advanced packaging. Ellery Buchanan's article, Wafer Bumping: An Industry Perspective, on page 43, covers this topic well. As end-user applications require complex and functional forms of device packaging, the need for advanced packages has increased rapidly. Buchanan reviews how wafer bumping has specific steps, one of which is lithography. He describes how steppers and other normally front-end lithography equipment must now be used in imaging for wafer bumping. In other words, the back-end uses front-end equipment where it makes sense. Thus, more front-end equipment is sold for packaging. Advanced packaging shows high growth, and the process steps reflect an understanding of what is needed.

Therefore, AP.will look into future applications for stories. One noteworthy addition to AP in 2004 is a department called Notable Developments. This department is intended to highlight advanced packaging R&D activities at universities and labs. In January's issue, IMEC presented their research efforts to develop connections between biological neurons and chip scale packaging. In this issue, George Harman, an international expert in wirebonding and packaging of semiconductor chips, talks about electronics interconnections designed for extreme environments. Last month, NASA landed two rovers named Spirit and Opportunity to explore the surface of Mars, gather geologic information, and beam results back to Earth. One of the major concerns is the cold Martian winter when temperatures dip to –120°C. Apparently conventional wire bonds using Au-Al may work fine in low-temperature environments. But when extremes in low and high temperatures occur, fatigue damage can result. How has NASA faced this materials issue? Harman examines what happens in this unique area. You won't want to miss this article.

Do you have an interesting development at your company? If so, please give me a call at (603) 891-9395. Work that gives you a driving force is worth sharing. As your magazine, we share your excitement.

Gail Flower

Editor-in-Chief