Good news/bad news: Packaging and wafer fabs converge
07/01/2001
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When we look back on 2001, we will likely remember it as the year that the long-heralded convergence of packaging and wafer fab processes really turned the corner, with convincing advances on many fronts. While it might not be a good year to have your wagon hitched even more tightly to the semiconductor industry, the "marriage" is now inevitable. There is simply too much to be gained with wafer-level packaging processes to put this off any longer.
The technical and economic benefits of wafer-level processing in the packaging arena have been described in detail for years, but I see some more subtle - but no less significant - benefits. Processing items that are physically connected - as opposed to just single items that are "batched" together in strips or trays - makes you think about your processes quite differently.
For example, a yield loss at a wafer-level step provides a better opportunity to learn something about that process, because the passing and failing parts, as part of the same wafer, have more in common. In effect, there are better built-in control lots for the continuous experiment of the production line. Wafer-level processing brings a certain sophistication to the factory that hasn't always been found on the packaging floor.
Wafer-level processing has also shown us that integration of processes into a functioning manufacturing flow is where many of the biggest challenges are to be found. The IC industry regularly introduces great new dielectric materials, for example, only to find that inserting them into the flow reveals all kinds of issues that hadn't been anticipated. The industry has learned that this history repeats itself, though, and these issues are now being addressed up-front more often. This is another thing that a wafer-level processing mode will bring to the packaging world - it can only help to have the packaging engineers thinking harder about the processes that come before and after their slice of the flow.
One sign of this trend is the greater involvement of front-end semiconductor equipment companies in the packaging world. In my recent post as an editor at Solid State Technology magazine, I saw an increasing portion of the articles and news items in packaging coming from Semitool, Ultratech Stepper, Electroglas, Karl Suss and other companies closely associated with wafer processing. Look for these companies and efforts by collective forces, such as the SECAP wafer-level packaging consortium, to prod the wafer and packaging industries down the aisle.
At SEMICON West, that 50-mile trek from San Francisco's front-end conference to San Jose's back-end event might seem like a prohibitive deterrent - especially if you're driving it anytime between 5 a.m. and 9 p.m. these days in Silicon Valley - but the gap is only a geographic one. Technologically, they are closer than ever. AP
Thanks for reading,
Jeffrey C. Demmin
Editor-in-Chief
[email protected]