French EUV development program under way

06/01/2000

Falling in line with other extreme-UV lithography development programs, CEA, France's atomic energy agency, has embarked on its own EUV effort, with an initial goal of developing a test bench capable of exposing EUV resists. Work on the program, known as PREUVE, is already under way at three CEA departments, including LETI, CEA's advanced technologies unit, where researchers are exploring EUV mask development, including multilayer deposition and patterning. Two separate CEA departments — the department of materials science (Drecam) and the department of military applications — are developing laser solutions, with the laser decision planned for next year, noted Jean-Charles Guibert, program manager for LETI's microelectronics department.

EUV is expected to enter production at the 70nm node and be in full production at the 50nm node, according to researchers at a next-generation lithography (NGL) meeting sponsored by International Sematech late last year. The PREUVE project is seeing only $10-20 million in funding, but will be able to capitalize on previous CEA EUV research. In the US, research into EUV, involving 13nm radiation and multicoated resonant reflective optics, has been under way for a number of years at Sandia National Laboratory's Livermore unit in California. Work is also on-going through Lawrence Livermore National Laboratory, and in 1997, Intel led an effort to form the EUV-LLC, a privately held corporation. Similar programs have also been established in Japan and elsewhere in Europe.

Guibert said PREUVE was launched after LETI engineers began exploring EUV through US EUV/NGL programs, and found CEA already had made progress with EUV research. With 16,000 engineers, CEA is a military and industrial research agency with an annual budget of $3 billion. For PREUVE, "the ultimate goal is to develop IP and to build a test bench able to expose resist at EUV wavelength," said Guibert.

To date, CEA has been able to develop EUV sources. "Some are not optimized for the wavelength or the repetition rate, but the material is here," Guibert said. "Presently, we are adding IP to our background. Optics design is on-going at SAGEM-REOSC, mainly [for] mirrors." SAGEM is known through its REOSC plant for telescope mirrors. Optics, masks, and instrumentation are being developed in parallel. Other participants include Sopra (for ellipsometers) and Seso, a provider of mirrors for synchrotron applications. "We are open to any collaboration," Guibert said, adding that PREUVE expects to collaborate with the existing EUV programs both in the US and in Europe. —C.L.

Munich hosts upbeat Semi Europa show

Smiles were everywhere at Semi Europa 2000 last week, amid bustling "stands" (booths) in Munich's sparkling new Trade Center, built on the site of the former city airport. Sales for many companies are taking off, show attendance was up, more companies (1174) showed more products than even last year, which was the first since the Pan-European show moved here from Geneva.

The industry upturn was reflected in the growth of the show, to 2112 stands this year covering 19,008 sq m (1850 last year covering 16,650 sq m) and 1566 in 1998 in Geneva. Exhibitors climbed to 1174 this year, from 986 in 1999 and 940 in 1998. Pre-registration, up to 6517 from 4700 last year, also promised bigger attendance, estimated at 12,000 for 2000 vs. 9525 last year.

Many new products made their debut at Semicon Europa, some geared to the coming switch to 300mm wafers and some to the more automated fabs being planned to handle the heavier cassettes this will entail. The Saxony region around Dresden, where the first 300mm pilot line, SC300, now operates, had a busy stand, attracting executives from infrastructure companies, especially after Infineon announced plans to construct a 300mm fab there.

Here are some highlights:

• ASM Microchemistry introduced a new atomic layer CVD reactor, the Pulsar 2000, for ultrathin (<50Å), highly conformal, pinhole-free films over large areas. Short pulses of reactant gases are followed by inert gases in sequence to build up layers. Some chipmakers are already using the equipment for thin gate dielectrics of zirconium oxide even though the equipment is not yet fully qualified, according to Ernst Granneman, business unit manager of ASM International. Leakage currents are reportedly 3-4 orders of magnitude lower than for alternative films.
• Trikon, of Newport in Wales, introduced its Planar fxP CVD cluster tool for low-k Flowfill technologies, which the company says will handle today's subtractive Al circuitry but be upgradable for damascene processing to the 70nm node.
• SEZ introduced the 300mm Spin-Processor 304 for wafer cleaning and thinning applications, saying it is fully compliant with Semi's 300mm automation and communication standards.
• James Morgan, chairman and CEO of Applied Materials, said the company grew more than 50% in 1999, and now has more than 2000 employees just in Europe. He cited three waves of demand for new tools: shifts to sub-180nm linewidths, the shift to copper and other new materials, and the transition to 300mm wafers. When asked whether any slowdown in end-use markets might slow this transition, Morgan replied that he sees economies on the upswing all over the world. David Wang, president of Applied, said that fast-rising demand had forced the company to double its output of process tools/week over the last four weeks, putting a strain on its suppliers. He said chipmakers had become much more open about their plans in the last few months.
• Novellus announced that the one-millionth copper wafer had been produced on its Sabre copper electrofill tools. Gasonics has been added to its array of partners, according to Wilbert van den Hoek, executive VP of integration and advanced development, because resist stripping becomes critical as low-k dielectric is combined with copper interconnects. Gasonics has been developing a suitable oxygen-free, hydrogen-based resist strip, he said.
• ASM Lithography announced a new, higher-throughput 248nm, KrF stepper for 130nm design rules, the PAS 5500/750E, while extending its estimate for production-worthy 193nm ArF tools until the second half of 2001. Meanwhile, the company says it is developing an entirely new platform for 300mm wafers, to be announced in the next few months, which will be suitable until the 70nm node.

The evidence of more and more joint development projects and partnering arrangements was everywhere at the show, as vendors strive to meet ever-more difficult process challenges for shrinking circuit features and new material sets.

Other developments at Semicon Europa 2000 included:

• A "Sea of Lots" concept for automating transport and storage of FOUPs and SMIF pods was demonstrated by Ortner CLS GmbH of Dresden. Wafer batches awaiting processing are stored in the plenum above the cleanroom, right over the bay containing the tool to be used. An overhead Interbay Conveyor System moves lots from one process to the next in sequence, under the control of a material control system linked to the manufacturing execution system software. Intermediate storage sites, or stockers, are completely eliminated. A 6-axle robot allows lots to be arranged in three lines along a linear track, providing storage for more than 300 lots in a bay.
• FSI International is teaming up with a number of US and European manufacturers to develop environmentally friendly wafer-cleaning and resist-stripping processes using ozone-based chemistries, which reduce the amount of chemicals and water needed. Through Metron, its European distributor, FSI is partnering Philips, at its Eindhoven labs, to do a demonstration project for its worldwide fabs, and with one other European manufacturer, as well as AMD in the US.
• JIPElec uses a high-power UV source for low-temperature, rapid-thermal anneals, to assist densification and crystallization for sol-gel, MOD and CSD processes. Post-annealing temperatures can be reduced for ferroelectric and high-k materials, such as PZt, SBT and BST.
• Entegris introduced a 300mm lightweight polycarbonate carrier for transporting and shipping wafers. Its FabFit Front Opening Shipping Box offers 40% space saving over present FOUP and FOSB carriers for 300mm wafers, the company says. Entegris is working with Sematech to meet standards needed for wafer transport. —B.H.