S E C T I O N S

Industry ViewpointBridging the Gap to 300 mm Wafers

By Dan HutchesonPresident, VLSI Research, Inc.

Is the transition to 300 mm wafers dead? Have the highcost of 300 mm tools and the current industry down-turn ended wafer-size transitions? No, but these factorshave caused the industry to look for more cost-effectivetransition strategies. One of the most promising strate-gies is the development of bridge tools.

The transition to 300 mm wafers has been identified as akey step in maintaining profitability in an era of shrinkinggeometries and increasing device complexity.Unfortunately, higher costs paired with the current downturnhave prevented the industry from simultaneously transition-ing to both 300 mm wafers and the 0.25, 0.18 or 0.15 µm device generations as previously expected. Thenext window of opportunity will occur around 2001-2004, coincident with the adoption of the 193 nm lithog-raphy tools needed to manufacture 0.13 and 0.10 µmdevices. If the industry misses that window, I believe it willbe the end of wafer-size transitions.

The shift to 300 mm may be even more difficult to accom-plish in 2001 than it would have been now, if it requiresextensive construction of new fabs. Although I expect theindustry to be in a strong upturn by that time, it will still befinancially strapped as it attempts to both increase capac-ity for existing generation products and finance the transi-tion to 0.13 geometries for advanced devices. It is, there-fore, critical that we find a low cost, low risk means of

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facilitating this transition; and I believe bridge tools are thesolution.

To deliver on that promise, bridge tools must meet three key criteria. They must have the ability to handle either200 mm or 300 mm wafers with easy upgrades. For anygiven process, the 200 mm version of the bridge tool mustdeliver a combination of footprint and throughput thatresults in a smaller floor space requirement than that of theprevious generation of 200 mm tools. Finally, the cost ofownership for a 200 mm bridge tool at a particularprocess step must be less than that of the current genera-tion of 200 mm tools.

If the industry begins the shift to bridge tools now, it shouldbe able to surmount the key challenges I expect it to facein 2001. It will be able to respond quickly to increaseddemand for capacity by transitioning from 200 to 300 mmwafers without incurring massive construction costs. Inaddition, it will have production-proven 300 mm platformsthat will help speed the ramp to full yield for new 0.13 µmadvanced devices — a critical factor both in meetingdemand and increasing profitability.

G. Dan Hutcheson is president of VLSI Research, Inc.,a company specializing in market research and economic analysis of the semiconductor manufactur-ing industry.

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