By Jeff Dorsch
The semiconductor industry’s transition to manufacturing on 450-millimeter silicon wafers is coming, whether you like it or not. It’s time to get on the bandwagon or to watch the parade.
At the same time, it is clear that only a small number of chipmakers will initially take the plunge into 450mm wafer fabrication. This transition in substrate diameters may go on for some years before it takes hold throughout the industry.
Suppliers of front-end and back-end production equipment have been hard at work for years already, updating their product lines to handle 450mm wafers. Silicon wafer manufacturers have been at it, too, to provide the necessary blank substrates.
Brian Trafas, KLA-TencorBrian Trafas, chief marketing officer of KLA-Tencor, says his company and others have “a lot of interest in helping with the transition.” Semiconductor manufacturers want to “make sure the yield is better on the larger substrate,” he adds. The bounty in extra chips per wafer is a key consideration, too.
“We help wafer manufacturers with the quality of the wafers they’re making,” Trafas notes. The industry roadmap calls for 450mm wafer fabrication to begin in 2018, he says. “Wafer manufacturers need to make wafers long before that,” he observes.
KLA-Tencor began developing 450mm-capable process control and yield management equipment “four or five years ago,” Trafas says. A year ago at SEMICON West, the company announced the first installations of the Surfscan SP3 450, a 450mm-capable unpatterned wafer inspection system. “We sold some to wafer manufacturers,” Trafas reports.
For now, KLA-Tencor is “focusing to continue to strengthen our (450mm) portfolio,” he adds.
Kirk Hasserjian, Applied MaterialsKirk Hasserjian, vice president of strategic programs for the Silicon Systems Group of Applied Materials, gives general details about his company’s activities in 450mm-capable wafer processing equipment, while not giving away too many specific details. “We’ve got activities ongoing to what our customers need,” he says. “We’re trying to stay close to our customers, the key customers who are driving it.”
Unlike the days of transitioning from 200mm wafer fabrication to 300mm, “the industry is highly synchronized” now, Hasserjian says. The industry now has a keen financial interest in making certain that “R&D dollars being put into 450 are invested in the right way,” he adds.
The Global 450 Consortium is coordinating many efforts around development of 450mm wafer fabrication, the Applied executive says, and Europe is seeing “a number of activities” in the field, at imec and elsewhere, he notes. SEMI and SEMATECH contributed 450mm standards early on, and “that helps quite a bit,” Hasserjian says.
While a number of 450mm consortia in addition to G450C have sprung up around the world, “I don’t see things coming up as conflicting,” Hasserjian notes. “That was true of 300 millimeter.”
Risto Puhakka, VLSIresearchRisto Puhakka, president of VLSIresearch, the market research firm, isn’t as sanguine about the progress of the 450mm transition. “Intel is the proponent of 450 millimeter,” he says. “I don’t see Samsung, TSMC moving on it. It’s pretty hard for the equipment guys, with one customer. The other guys aren’t moving along.”
Still, “the programs are moving,” Puhakka adds. Taiwan Semiconductor Manufacturing, the world’s largest silicon foundry, plans to have 450mm fabs up and running in 2016, he notes.
Two years ago, EV Group introduced the EVG850SOI/450 mm system for bonding 450mm wafers made from silicon-on-insulator substrates. Soitec took the first delivery of the system in 2011. To handle the multiple types of technology used in the industry, “we have three to four process models in process,” says Paul Lindner, executive technology director at EV Group. “They will be made available soon.”
In the future of back-end equipment, wafer-level package assembly “will be highly important with 450 millimeter,” he says.
Due to the larger size and weight of the substrates, wafer handling must be completely automated for 450mm wafers, according to Lindner, with automated wafer loading into equipment, fully automated front-opening unified/universal pods (FOUPs) and robotics.
At SEMICON West this year, there are several programs where the 450mm transition will be discussed. On Wednesday, July 10, a session called “Silicon Wafers – Future Standardization to Enable the Transition” will be held at the Marriott Marquis Hotel, beginning at 2:30 p.m. The program summary notes, “Since 2008, SEMI has published fifteen 450mm wafer standards, guided by customer requirements and supplier feedback. These specifications, covering wafers, carriers, and loadports, have enabled the industry to continue the development of equipment, materials, interfaces, and processes, but further standardization will be necessary for a successful transition to manufacturing on 450mm wafers.”
On Thursday, July 11, the SEMICON West 450mm Transition Forum will be at 10:30 a.m. at TechXPOT South, in the South Hall of Moscone Center. The forum will include presentations by Kirk Hasserjian of Applied Materials, Paul Farrar of the Global 450 Consortium, Brian Trafas of KLA-Tencor, Hamid Zarringhalam of Nikon Precision, Chris Richard of PricewaterhouseCoopers, Jonathan Davis of SEMI and Akihisa Sekiguchi of Tokyo Electron Ltd.
The program summary says, “Increased levels of collaboration, further advancements in tool prototypes, and increased visibility into related supply chain implications have occurred over the past year as the semiconductor industry implements the capability to manufacture its products on 450mm wafers. The SEMICON West 450 Transition Forum will provide the latest updates on the status of 450 R&D, as well as a review of key technology considerations and a discussion of implications and opportunities for the supply chain.”
The 450mm transition, as some have noted, is proceeding in a more orderly, cooperative process than the 300mm transition, which suffered from top-down dictation to semiconductor equipment and materials vendors. It remains to be seen whether those vendors will feel better about 450mm than they did about 300mm in the beginning, when they had to absorb research and development costs that weren’t rewarded with orders for 300mm equipment.