Category Archives: Metrology

July 22, 2002 — Veeco Instruments Inc., a Woodbury, N.Y., manufacturer of metrology tools, announced that its metrology group has created a technical advisory board to promote the company’s leadership in measurement instrumentation and nanoscale technology.

The seven-member board will meet regularly to provide feedback on company efforts and to point out areas of nanoscale research that may be fruitful for the company.

The board will be chaired by John Carruthers, former director of components research at Intel. He is joined by Jeffrey Bokor of the University of California, Berkeley, department of electrical and computer sciences; Julio Fernandez, chair of the Mayo Clinic’s single molecule mechanics and engineering lab; James Gimzewski of UCLA’s department of chemistry and biochemistry; Joseph Kirk, former senior engineer at IBM; Calvin Quate of Stanford University’s departments of electrical engineering and applied physics; and Don Sweeney of Lawrence Livermore National Laboratory.

By Rachel Robinson
WaferNews Associate Editor

In the expensive and complicated world of integrated metrology, a different approach could get customers interested in a concept that may work better – while also being cheaper, simpler, and less intimidating.

Tevet Process Control Technologies, Yoknea’m, Israel, is one company trying to provide just such a metrology solution.

After making headlines recently for hiring a new president, Yuval Wasserman, and for raising an undisclosed amount of money in series B financing, Tevet is shifting its status from R&D and product development to market entrance and (soon) growth.

Tevet is hoping to provide “quick and dirty” metrology to end user IC companies and to OEM equipment manufacturers.

Its concept, according to Wasserman, is simple, “Tevet took a fresh look into the need [for integrated metrology] – using a clean slate.”

In a nutshell, the company’s approach relies on broadband relfectometry and using a large spot size.

“If you look at a lot of tools, you have a small spot size to measure thickness,” Wasserman told WaferNews. “Tevet has a large spot size – almost the whole chip.”

He said that the wafer is placed under a measurement head and all the measurements can be done at once. “Because it’s a large spot size, there is no need for pattern recognition, auto-focus, or vision in the system, which therefore reduces costs and increases reliability.”

The Tevet system has multiple sensors; if one wants to measure five points, the system will have five sensors. If one wants to measure nine points, it’ll have nine sensors.

According to Wasserman, measurement is done in three seconds for the whole wafer, allowing it to measure a rotating wafer. Measurement can be done on spin-on dielectric or spinning resist, he added.

Wasserman said that Tevet’s tool could handle transparent films such as CVD depositition or spun-on dielectrics, low-k dielectrics, and photoresist. The system can handle stacks too, he added. It can measure a thickness range of 1,500 to 50,000 angstroms.

“The uniqueness of Tevet’s technology is the fact that by using a large spot size we collect information that allows us to measure the plurality of thickness in the measured area,” Wasserman said. “It means that we don’t have to carefully position a small spot on a chosen area to measure one film thickness and also, it relieves us from the need to utilize vision, pattern recognition, accurate positioning stage, and auto focusing systems thus reducing cost and increasing reliability.”

Wasserman said that Tevet’s competitive edge is that its metrology tool can sit on top of a platform and remotely tally non-invasively and perform measurement without mechanical changes to the platform itself.

He said this is possible by utilizing a window above a wafer handling mechanism and by placing the measurement tool on top of it. “In two beta sites,” Wasserman explained, “we performed beta tests in a fab area where Tevet’s metrology tool was put onto a CVD cluster tool and did the test non-invasively.”

He went on to say that Tevet also tested on another CVD cluster tool where the metrology unit was placed above a cooling station.

Wasserman joined Tevet, which is the Hebrew equivalent for January, from Boxer Cross Inc., where he was senior VP of sales and marketing. He comes into his new role with set goals. Wasserman said that the company is going to add resources to support an initial phase of sales and marketing and then shorten the distance between the company’s development center in Israel and its worldwide customers.

“I envision running the company with two heads, or two legs – R&D in Israel, taking advantage of government incentives and local talent in metrology, while the business [aspects] like sales and marketing will be in the [San Francisco] Bay area, making sure that we address market needs.”

WaferNews

WOODBURY, NY, and HILLSBORO, OR, – Veeco Instruments Inc. and FEI Co. have penned a definitive merger agreement to combine the companies into one provider of 3-D metrology and process equipment.

FEI will become a wholly owned subsidiary of Veeco, and Veeco will be renamed Veeco FEI Inc. The company will continue to trade on the Nasdaq market under the ticker symbol VECO.

The agreement was unanimously approved by the boards of directors of both companies, and FEI stockholders will receive 1.355 shares of Veeco common stock for each share of FEI they own.

Based upon FEI’s approximately 32 million diluted shares outstanding, the FEI stockholders will receive approximately 44 million Veeco FEI shares with a current value of approximately $1 billion.

The merger, which will be accounted for using the purchase method, is intended to be tax-free to FEI stockholders, and is expected to close during 4Q02.

Veeco and FEI managements currently anticipate operating
synergies of approximately $8-10 million on an annualized basis resulting from integration of the companies’ sales and support networks, supplier management, and manufacturing and administrative efficiencies.

Vahe A. Sarkissian, FEI’s Chairman, President and Chief Executive Officer, will become chairman of the board and chief strategy officer of Veeco FEI; Edward H. Braun, Veeco’s chairman, president and CEO, will remain CEO and president.

Veeco FEI’s board of directors will have 13 members, seven of whom are current members of Veeco’s board (including Braun), five of whom are current members of FEI’s Board (including Sarkissian), and one of whom will be designated by Philips Business Electronics International B.V., a significant stockholder of FEI.

John F. Rein Jr., Veeco’s exec. VP and CFO, will remain CFO of the combined company.

Veeco FEI’s corporate headquarters will be located in Woodbury, NY, the
current Veeco headquarters, and FEI’s current headquarters in Hillsboro, Oregon will remain a significant facility for Veeco FEI as a center of research and development and manufacturing. Veeco FEI will have approximately 2,900 employees at its key facilities in North America, Europe, Japan and the Asia-Pacific region.

Braun commented, “Based on combined 2001 sales of $825 million, together we become the sixth largest U.S. semiconductor equipment company and the third largest US supplier of metrology equipment.”

July 12, 2002 — Veeco Instruments Inc. of Woodbury, N.Y. and FEI Co. of Hillsboro, Ore., announced today the signing of a definitive merger agreement to combine the companies. Both companies develop and manufacture process equipment and metrology tools.

As a result of the merger, Mark Miller, a securities analyst with Hoefer and Arnett, upgraded Veeco from a hold to a buy.

Under the agreement, approved by the boards of both companies, FEI will become a wholly owned subsidiary of Veeco, which will be renamed Veeco FEI Inc. The combined company will continue trading on the Nasdaq market under the symbol VECO.

Pending stockholder and regulatory approval, FEI stockholders will receive 1.355 shares of Veeco common stock for every share of FEI stock. The merger is expected to close during the fourth quarter of 2002.

Based on combined 2002 sales of $825 million, the two companies combined would constitute the sixth largest U.S. semiconductor equipment company and the third largest U.S. supplier of metrology equipment.

July 11, 2002 – Milpitas, CA – Nanometrics Inc., a supplier of integrated and standalone metrology equipment, has introduced its next-generation stage technology platform.

Designed to be the foundation for Nanometrics’ metrology for years to come, the 300mm metrology platform offers users enhanced performance and simplified process tool integration in an ultra-compact package, the company said. The new atmospheric stage technology is compatible with Nanometrics’ next-generation measurement and inspection technologies and all of its current metrology products.

The R-theta stage technology is compatible with 300mm high volume manufacturing requirements, including high throughput, an edge-gripping wafer chuck, and integral wafer alignment, all without backside contact, Nanometrics said. Edge gripping ensures that there is no wafer yield loss due to backside particulate contamination. In addition, optical pre-alignment technology is integrated into the stage, which means that it only has to be performed once.

Using Nanometrics’ patented R-theta technology, the platform offers high precision capabilities that reduce the total search time needed to perform pattern recognition, Nanometrics touted. This increased accuracy means that the platform enables repeatable placement onto smaller measurement pads without additional pattern recognition steps on product wafers. The new platform boasts a slew rate of 15 inches/second, according to the company.

Nanometrics lowered the number of components and cables required by the new technology to simplify its integration into OEM process tools. The controller, power supplies, optical pre-alignment technology, and character recognition have all been included in the platform, reducing the total number of additional components that users must integrate into the process tool, Nanometrics said. Additionally, the new platform will facilitate multiple Nanometrics measurement and inspection technologies onto a single platform.

Hillsboro, OR – FEI Co. has joined equipment suppliers Novellus Systems, Lam Research Corp., and SpeedFam-IPEC in the Damascus Alliance industry consortium, founded in 1998 to tackle the technology transition to copper dual damascene manufacturing.

With the installation of a DualBeam metrology system at the Customer Integration Center, FEI will bring sub-surface defect sourcing and 3-D metrology to alliance customers.

The Customer Integration Center is located at Novellus’ Silicon Valley campus.

Operating as a formal, cross-company collaborative effort, the Damascus Alliance is designed to help customers solve their unit process integration problems, give them access to advanced copper technologies and state-of-the-art toolsets, and help them fine-tune their dual damascene processes to deliver a reliable, cost-effective interconnect structure.

“The role of the equipment suppliers in the semiconductor industry is changing,” said Wilbert van den Hoek, CTO and executive VP for integration and advanced development at Novellus. “We still need to supply state-of-the-art equipment and unit processes, but with the changes to new materials and manufacturing methods, there’s also a role for equipment companies to assist customers with optimizing their process flows, and helping to accelerate their production yield learning.”

In addition to the DualBeam metrology system, FEI will supply full-time, on-site applications specialists, experienced in advanced sub-surface critical dimension and defect sourcing applications, to the Alliance’s Customer Integration Center.

By Drew Wilson
WaferNews Asian Correspondent

Asia’s big chipmakers have been embracing metrology systems as technology changes come on stream, devices grow in complexity, and time-to-market pressures escalate.

“Today it’s critical to keep fabs operating at optimal yields as much as possible,” says Risto Puhakka, VP of operations for VLSI Research Inc. “That’s the key issue that keeps driving metrology.”

FEI Co., Hillsboro, OR, which makes equipment for structural process management, has its dual beam inspection systems helping TSMC’s Fab 12 go from a few wafer starts/month to 10 times that by year’s end, says Jay Lindquist, VP of FEI’s microelectronics product group. The machines promise to save chipmakers time and money by providing a 3-D view below the surface of the defect area, right on the production line.

“The big push right now is to bring in tools so customers can get a manufacturing line to the point where it’s ready to ramp up,” Lindquist adds.

Asia sales make up more than 30% of FEI’s $376 million in sales and include powerhouses such as UMC, Samsung Electronics, Elpida, and NEC.

Another metrology company, Rudolph Technologies Inc., Flanders, NJ, derives 50% of its $80 million revenue from Asia. Customers include the major Taiwan foundries plus Chartered Semiconductor in Singapore and a list of Japanese and Korean chipmakers.

Rudolph makes metrology tools that essentially improve yield. For example, the company’s sonar-based technology called Metapulse measures the thickness and quality of the films that are involved in the 500-some process steps it takes to turn a silicon wafer into functioning state-of-the-art computer chips, explains George Collins, Rudolph’s VP of marketing.

If the films are too thick or thin, or not laid down or removed properly in the photolithography process, then the wiring that connects maybe 20 million transistors on the chip will create defects.

Asia began buying pulse sonar technology about two years ago. Collins believes sales are still in an early phase.

“Some capacity out there is one or two generations old,” he says. “When high volume production returns, retooling to a new generation will require many metrology tools.”

Technology transitions introduce uncertainty into the chipmaking process and metrology equipment can quickly tell the manufacturer what’s gone wrong and where.

Copper wiring, for example, is problematic, and has high defect rates. While FEI’s systems have the ability to spot voids in a copper structure, Rudolph’s Metapulse helps in laying down the wire properly in the first place.

Collins says Rudolph has sold systems to nearly all of the 20 or so chip companies that announced the adoption of copper.

Another technology change is in lithography, which is pushing the laws of physics by using wavelengths of light much larger than the features that are being printed. FEI’s metrology systems help address phase shifting and proximity correction problems, Lindquist says.

Then there’s the 300mm wafer, which is more costly than 200mm, but can produce 2.4 times more chips that probably carry high ASPs. FEI’s focused ion beam system has been attractive because it doesn’t waste the whole wafer to analyze one chip defect. The system could single out one faulty chip on a 600-chip wafer. In the past, a whole wafer might be cleaved to analyze one defect, losing $5,000 to $20,000 worth of revenue, depending on where it was in the production process.

Rudolph’s Collins adds that a 300mm wafer with microprocessors could be worth about $100,000. Saving only 10 wafers in a 20-wafer cassette by identifying them as good early in the process adds up to $1 million saved.

Typically a fab uses six to 10 of Rudolph’s tools. In a 300mm format, which can run as high as $1.5 million for each tool, the fab can see a payback in six to nine months, Collins claims.

VLSI sees the process diagnostics market, which includes metrology, slightly down in 2002 to $3.4 billion from $3.6 billion last year. But over the long term, the process diagnostics share of all chipmaking equipment is growing, Puhakka says.

“The information you derive from metrology can be used to drive your processes — and that’s why the value is continuously increasing,” he adds.

WaferNews

WASHINGTON — The National Institute of Standards and Technology (NIST), the federal agency dedicated to the science of measurement, made it clear during an open house Thursday that it’s serious about measuring material on the nanoscale.

During a daylong preview of NIST’s various commitments to nanotechnology, scientists touted their research in fields ranging from nanostructure physics to chemical nanoanalysis metrology to single-electron devices.

Establishing standards and measurements on the nanoscale, said several presenters, is an increasingly important task for NIST.

“This is all about measurement,” said Robert Celotta, the leader of NIST’s Electron Physics Group during his presentation on nanostructure physics. “Nanotechnology is a big area for us.”

The growing importance of nanotechnology to the federal government at large was underscored by Benjamin Wu, deputy undersecretary for technology in the U.S. Department of Commerce. President Bush demonstrated his commitment to nanotechnology by calling for a 17 percent funding boost in the National Nanotechnology Initiative, Wu said, adding that the president recognizes the world is in the middle of a race for nanotechnology supremacy.

The launching of NNI, Wu said, “was like the shots fired at Lexington — it was like the shot heard around the world.” Former President Clinton started the NNI in 2000.

NIST now has about 100 ongoing nanotechnology-related projects, representing about 6 percent of the federal government’s nanotech research investment. Bush is budgeting about $43 million in the 2003 budget for nanotechnology research within NIST.

At a dinner for the National Electronics Manufacturing Initiative the night before NIST’s open house, NIST Director Arden Bement delivered a long speech dedicated to nanotechnology.

“What do we see as the unique NIST role in nanotechnology?” he asked. “Measurement is the answer, of course … The NSF may be right when they say that we’ll see a $1 trillion nanotech market by 2011, but we’ll need a strong metrology infrastructure to get there. And that’s what we do.”

Eric Steel, leader of the microanalysis research group at NIST, said at the open house that nanoengineered powders and films figure into his group’s research. The products, he said, could be instrumental in stealth technologies that let jets fly without being detected by radar, for example.

But these materials need measurements down to the single-atom level, and the science just isn’t there yet, he said, although it’s getting closer. One problem is that as scientists improve the sensitivity of probes, they lose spatial resolution. NIST researchers have worked on using cluster ions to simultaneously gain sensitivity and spatial resolution. The technique, he said, is promising.

The agency is also doing work in nanobiotechnology, particularly in tissue engineering. In one project, NIST scientists are building tools that will find and manipulate single atoms in biologically active materials. In addition, through the NIST Center for Neutron Research, the agency is collaborating with the University of California, Irvine, to build the first neutron-beam research station dedicated to biological membrane experiments.

NIST researchers are also involved with development of new materials that can, for example, better withstand heat from fires. The polymeric materials group, led by Mark VanLandingham, is researching the fire-resistant properties of new materials that are formed when organic resins are reacted with nanoscale clay particles.

Bement has taken to talking-up nanotechnology regularly in recent months, and it’s clear that nanotechnology isn’t dropping from the agency’s agenda anytime soon. In closing his speech at Wednesday’s dinner, Bement offered “one additional suggestion as you consider the future.”

“Think small,” he said. “Very small.”

June 13, 2002 – Menlo Park, CA – Boxer Cross Inc. has filed a counter-suit for patent infringement, trade secret misappropriation, and unfair competition against Therma-Wave Inc.

The counter-suit was filed in US District Court on June 7 in connection with the litigation filed by Therma-Wave on April 22.

The Boxer Cross counter-suit claimes three violations by Therma-Wave. First, the counter-suit claims that Therma-Wave’s application of its Therma-Probe infringes on Boxer Cross’ patents No. 6,049,220 and No. 6,323,951. Second, it claims that Therma-Wave misappropriated trade secrets related to Boxer Cross’ technology developments in metrology. Finally, it claims that Therma-Wave has engaged in unfair competition and business practices against Boxer Cross.

By Pieter Burggraaf
WaferNews Technical Editor

Perhaps under emphasized relative to the red brick wall associated with scaling CMOS, as early as 2004 “manufacturable solutions are not known” looms for many 2001 ITRS facets of factory ramps, equipment lead time, factory cycle time, throughput, maintenance, material handling, and the intertwining importance of factory information and control hardware and software.

Specifically for material handling, the ITRS requirements are that automated material handling systems (AMHS) must interface directly with all 300mm tools used in a normal production process flow, while providing acceptable ROI. The roadmap states, “Solutions to provide higher wafer storage densities, short lead and install times, and better utilization of floor space through integration of process and metrology equipment must be developed.” Further, the ITRS specifically states the need to combine interbay and intrabay AMHS into one integrated capability (i.e., a “unified” tool-to-tool transport system that replaces conventional “segregated” interbay and intrabay approaches), all within the context of lower failure rates and faster repairs, substantially increased throughput, and designs that accommodate extendibility, flexibility, and scalability demands on the factory.

Using discrete event simulation, engineers at PRI Automation, Billerica, MA, have evaluated 300mm fabs with fully unified AMHS (a single OHT system throughout the fab), partially unified (still using interbay transport, but with several bays of OHT “linked” together), and a combination of both, all compared to conventional segregated AMHS on several criteria — equipment set, lot delivery times for normal lots and hot lots, relative reliability, relative cost, and implementation considerations. These simulations here done for a bay-chase and ballroom fab, with similar results for both.

The data for the bay-chase fab, for example, clearly showed that the total number of material handling moves was less for the unified configuration, simply because every tool-to-tool unified move requires only two transports, as opposed to three in a segregated configuration. Although, the total required storage space for WIP remains between each configuration (since WIP level is driven by manufacturing factors, not by AMHS design), the number of stocker cycles required to accomplish lot moves decreases for a fully unified system. In the modeled segregated system, 22 stockers were required because at least one stocker was needed in each bay (bay with high intrabay activity and lot move frequency require more stockers). But the unified system required only 15 stockers, since less stocker work is required and adjacent bays can share stockers.

As a result of requiring fewer stockers, the system costs of the linked and unified configurations are lower. It is worth mentioning that more OHVs are required in the unified than any other configuration. However, fewer overall vehicles are needed with a unified system. This number could further decrease as more intelligence is added to vehicle dispatch system and as real time scheduled data is integrated with the material control system.

From this work, the PRI engineers concluded that unified AMHS had the highest MTBF and lowest system cost, the former correlated with fewer system components and the latter directly related to the need for fewer stockers (i.e., conventional segregated AMHS requires more stockers to support individual intrabay loops and handle more total lot moves). A unified approach also enabled more flexible tool placement with a saving of fab floor space; for example, a unified configuration takes advantage of the chase of repositioning of metrology tools so they can be shared between two bays. In addition, unified AMHS provided shorter tool-to-tool average delivery times — 32% lower for normal lots, 66% lower for hot lots. Lower delivery times for unified AMHS result because there are fewer lot hand-offs; this shortens the total transport and handling times and eliminates queue times for these unneeded hand offs.

According to Joe Reiss, director of strategic marketing for PRI Automation, it is generally accepted that the primary challenge to implementing unified AMHS is the sophisticated control software required. However, Reiss notes that PRI’s simulations were run using the same control algorithms found in PRI’s existing AMHS transport control and MCS software.

“In addition to showing the performance benefits of unified AMHS, our simulations demonstrate the ability of the AMHS software to manager the complex move-routing task of a single, large-scale transport network,” he says.

In ongoing work, these engineers are investigating the effect of AMHS configurations on fab performance using full-fab simulation. One fab configuration under evaluation is one used in a SEMATECH study that looked at various tool layouts considered for a 300mm fab. They are currently examining affects of Unified AMHS on wafer cycle time and equipment utilization.