Move to 230-mm reticle now on back burner
06/01/1998
Move to 230-mm reticle now on back burner
With critical level 230-mm (9-in.) reticles forecast to cost at least three times as much as today`s 150-mm masks, the need for the larger reticle size is being pushed out about a year, according to a recent survey of 13 mask producers` plans for 230-mm.
Eased in part by the delay of the 300-mm wafer transition, the 230-mm reticle move is "not as critical as it was a year ago. Lithographers see more leverage in tighter mask specifications," said Brian Grenon, of Grenon Consulting, Colchester, VT, which conducted the survey (Fig. 1).
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Figure 1. 230-mm reticle demand.
While most participants said they plan to integrate 230-mm reticles into their facilities over the next four years, Grenon found that 230-mm reticle development isn`t the top development priority. Taking priority instead is mask specification development, and reticle lithography development - considered by survey participants to be the biggest limiter to 230-mm reticle integration (Fig. 2).
"At some point, they are going to have to bite the bullet and go that way," Grenon said, noting that even with optical lithography options losing steam after 2006, the reticle need will remain. "The only way you`ll get rid of reticles is if you go to direct write. 230-mm will ultimately have to happen. What drives that is chip size. The real issue is going to be what these people are going to charge."
Grenon estimates critical level reticles will be at least three times more expensive than current leading edge reticles; noncritical level reticles will be about 1.8 times more expensive. For example, he said, a 230-mm resist-coated blank alone will cost somewhere between $5000 and $10,000, a striking hike over $800 to $1000 for comparable 6-in. resist coated blanks. Moreover, he said, for a leading-edge full mask set "you`re talking about paying $1 million," - a hard cost to leverage, particularly when a company must account for writing errors and other mishaps.
According to rough estimates, demand for 230-mm reticles will start to take off in 2000. Grenon estimates the industry will need 7200 reticles then, and 45,000 by 2004; this year "one or two Japanese will lead the way," supplying the industry with 200 production quality reticles, he said. "It`s important to keep in mind that the picture can change as technology demands change. Price pressures could push the move to use 230-mm reticles for higher throughput for 300-mm wafers, the need for multichip reticles or larger chip sizes." - C.L.
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Figure 2. Reticle development priorities