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Industry Viewpoint Bridging the Gap to 300 mm Wafers By Dan Hutcheson President, VLSI Research, Inc.
Is the transition to 300 mm wafers dead? Have the high cost of 300 mm tools and the current industry downturn ended wafer-size transitions? No, but these factors have caused the industry to look for more cost-effective transition strategies. One of the most promising strategies is the development of bridge tools. The transition to 300 mm wafers has been identified as a key step in maintaining profitability in an era of shrinking geometries and increasing device complexity. Unfortunately, higher costs paired with the current downturn have prevented the industry from simultaneously transitioning to both 300 mm wafers and the 0.25, 0.18 or 0.15 µm device generations as previously expected. The next window of opportunity will occur around 20012004, coincident with the adoption of the 193 nm lithography tools needed to manufacture 0.13 and 0.10 µm devices. If the industry misses that window, I believe it will be the end of wafer-size transitions. The shift to 300 mm may be even more difficult to accomplish in 2001 than it would have been now, if it requires extensive construction of new fabs. Although I expect the industry to be in a strong upturn by that time, it will still be financially strapped as it attempts to both increase capacity for existing generation products and finance the transition to 0.13 geometries for advanced devices. It is, therefore, critical that we find a low cost, low risk means of
facilitating this transition; and I believe bridge tools are the solution. To deliver on that promise, bridge tools must meet three key criteria. They must have the ability to handle either 200 mm or 300 mm wafers with easy upgrades. For any given process, the 200 mm version of the bridge tool must deliver a combination of footprint and throughput that results in a smaller floor space requirement than that of the previous generation of 200 mm tools. Finally, the cost of ownership for a 200 mm bridge tool at a particular process step must be less than that of the current generation of 200 mm tools. If the industry begins the shift to bridge tools now, it should be able to surmount the key challenges I expect it to face in 2001. It will be able to respond quickly to increased demand for capacity by transitioning from 200 to 300 mm wafers without incurring massive construction costs. In addition, it will have production-proven 300 mm platforms that will help speed the ramp to full yield for new 0.13 µm advanced devices — a critical factor both in meeting demand and increasing profitability. G. Dan Hutcheson is president of VLSI Research, Inc., a company specializing in market research and economic analysis of the semiconductor manufacturing industry.
Autumn 1998
Yield Management Solutions
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