(January 4, 2007) SAN DIEGO — StratEdge released the SMX series of surface mount ceramic packages for test-and-measurement, VSAT, point-to-point, point-to-multipoint, and WiMax applications. The packages, tested by JDS Uniphase (Bloomfield, CT), are designed with thermal management functions incorporated.
Category Archives: Materials and Equipment
January 4, 2007 – Taiwan government officials say ASML has chosen to establish a new $150 million facility in Taiwan as its R&D headquarters for the region, according to the Taiwan Economic News.
The report states that the Taiwanese government is providing perks including a five-year income tax break and untaxed royalties, as well as soliciting more suppliers to cluster around the new site in Taoyuan in northern Taiwan.
The decision is seen as a move to get closer to local chipmakers in Taiwan, including top customer TSMC. Taiwan is bustling with 300mm fab activity, plus most of the chip facilities in China are financially backed by Taiwanese groups, the paper noted.
Officials in Taiwan’s Ministry of Economic Affairs (MOEA) and Industrial Development Bureau (IDB) aim to achieve a local content rate of 60% for semiconductor equipment, and have been actively soliciting foreign companies to set up operations here — including display panel stepper suppliers and ASML rivals Canon Inc. and Nikon Corp.
In September the paper indicated that ASML was seeking to establish a new Asia-Pacific R&D center in either Taiwan or South Korea. The MOEA had proposed nearly a dozen possible sites for the new R&D center, which would require at least 36,000 sq. ft of space, including the Taoyuan site, the paper noted.
January 4, 2007 – CoorsTek Inc., a manufacturer of ceramics and electronics components, has acquired Ventura, CA-based Gaiser Tool Co., a ceramics precision tooling firm, for an undisclosed amount.
Gaiser invented the first alumina ceramic capillary in 1970, and a process for ultrafine-pitch bonding in 1997 to produce bottleneck-style premium ceramic capillaries.
CoorsTek says it will keep the Gaiser brand and absorb the company’s technical and material work. The deal will also expand CoorsTek’s microcomponent capabilities in various markets.
“Gaiser Tool invented the wire bonding ceramic tool market in the early 1970s and now leads the high end of it with quality and innovation,” said Mark Petty, EVP of CoorsTek Inc., in a statement. “We bring a significant level of technical ceramic expertise to this enterprise and expect customers and their industries to benefit substantially.”
January 3, 2007 – Taiwan’s government-funded Industrial Technology Research Institute (ITRI) has set an aggressive budget over the next two years to support research and development of flexible electronic technologies and products, according to the Taiwan Economic News.
Many bottlenecks in flexible electronics materials, device design, and production processes have already been addressed, noted Tang Yu-hwa, project manger of Industrial Economics & Knowledge Center (IEK) under ITRI, quoted by the Taiwan paper. The IEK estimates the flexible electronics market will mature in 2008, with sales rising sharply through 2010. Annual global production could potentially hit $16 billion by 2015, with devices including flexible logic, memory, and display products entering the mainstream.
The ITRI plans to invest about $27.27 million in 2007, and $30.37 million in 2008, for flexible electronic R&D, following similarly aggressive investments in prior years — in 2006 the institute spent about $15 million in 2006 on a new flexible-electronics experiment lab, the paper noted. By 2008 the ITRI aims to have ready its first product — printed passive RFID tags to replace traditional barcode systems — as well as a prototype of static flexible-display signage. More high-level static flexible display products such as e-paper and e-newspapers are expected by around 2010, with advances to big-screen TVs possible by 2015.
Flex circuits or flex circuit boards enable deposition of electronic devices on flexible substrates such as plastic, which can be used for circuit boards, or to replace LCD glass substrates with thin plastics or metal foils. Another product goal is the e-book, which could be based on organic materials and flexible substrates to create a more lower-power, portable product.
Playing golf has taught me a bit about work under pressure. I wouldn’t say that my golf game is bad, but if I grew tomatoes, they would probably come up sliced. Often in our industry I’m asked to give an awards presentation, or lead a panel or a keynote, and the easiest way to begin is to pretend that I’m teeing off at Pebble Beach. The pressure to hit the ball squarely with follow-through as the crowd judges every move is so intense that I can feel it. And the cost of the course alone demands a certain skill. Fear seems to heat up the surroundings. “Hey, this isn’t Pebble Beach,” I remind myself. This is just a meeting of friends in an industry I enjoy, waiting to be enlightened and entertained. In a moment, cool relief washes over me and my voice returns. Golf is self-inflicted pressure. The amazing thing is that it is so simple, the concentration required to do it well is like meditation. But teeing off the first hole creates heat.
Heat plays in important role in packaging as well. In the back-end, thermal design and analysis techniques are continuously adjusting to packaging’s changing structures. Incorporating additional functionality within each package, including combinations of lateral and stacked chips and other complex structures, creates interesting thermal engineering problems. Here “interesting” is the operative word, much like “unusual” – as it applies to my attempts at golf. To address thermal solutions for the back-end, MEPTEC will present their 3rd annual technical symposium February 15, 2007, in San Jose. Also, Georgia Tech Packaging Research Center and Binghamton University have partnered to form an industry-academia Thermal Interface Materials (TIM) Consortium. Fifty engineers worldwide have agreed to work on 12 TIM-related research projects. The TIM Consortium is expected to involve a total of 6 academic, 3 research faculty and 6 Ph.D. students to enable a 10× improvement in overall interface thermal resistance. Research efforts concentrate on novel thin film materials, TIM surfaces, interfaces and bonding, characterization, prototype testbed, and reliability. The TIM consortium launch date is set for June 1, 2007.
Everywhere in the news companies announce their latest products for heatsinks. For instance, Advanced Thermal Solutions, Inc., announced thermal management mechanical packaging solutions, the ATS-486, ATS-503, and ATS-504, for cooling OSRAM’s dragonstick LEDs and other linear LED lighting products. Additionally, this issue of Advanced Packaging offers an article (“Particle Atomic Layer Deposition”) on the incorporation of metal- and ceramic-filler additives to polymeric materials to give greater thermal conductivity on a nano-scale level.
A multitude of thermal solutions abound. So take a deep breath and begin research on how to deal with them. It’s good sportsmanship to not pick up lost golf balls while they are still rolling, according to Mark Twain. But some of these balls have stopped and are there for the taking.
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Gail Flower
Editor-in-Chief
First-ever UMass Lowell-Small Times analysis explores nanotech industry priorities
Although nanotechnology is generally considered a long-term research priority for the United States and other nations, most U.S. nanotechnology industry executives said that high volume manufacturing of nano materials and products is the most important activity required for the United States to strengthen its nanotech capabilities. The focus on high volume manufacturing outpaced long-term research by a factor of more than two to one.
The results were part of a survey of nanomanufacturing executives conducted by the University Of Massachusetts Lowell and Small Times. Of the 407 executives interviewed, 39 percent said that if the U.S. were to strengthen its R&D capability, high volume manufacture of nano materials and products would be most important. Only 15 percent chose “basic long term research.” A majority of executives (63 percent) said they see the U.S. as leading the world in nanotechnology research and development, with only 7 percent seeing the U.S. as lagging behind other countries.
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Moreover, the respondents don’t expect industry to go it alone. In fact, the vast majority of nanotech executives think government should play a role – either take the lead in R&D and commercialization incentives or at least participate in a limited fashion. But they are split between the two approaches, 45 percent wanting government to take the lead and 43 percent saying government’s role should be limited. Eleven percent said government should “stay out of it.”
More executives said their companies are integrating nanotech materials (88 percent) rather than currently manufacturing those materials (47 percent) themselves. (The overlap is companies that are involved in both manufacturing and integrating.) Nanocrystals, followed by nanotubes and nanoparticles, are seen as the most important nanomaterials to develop, manufacture and purchase over the next three years, and most companies currently manufacture or use those materials in that order.
The survey also clearly showed that nanotech industry executives think the role of government is not only to foster technical innovation, but to monitor its social and environmental side effects. In fact, there was near-unanimous consensus on the issue: 97 percent of executives think that government has an important role in addressing potential health effects and environmental risks of nanotechnology.
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This likely follows from the observation by 64 percent of the respondents that the risk to the public, environment and workforce of exposure to nanoparticles is currently unknown.
Despite the perceived environmental uncertainty, many of the respondents were also bullish on their own firms’ potential sales in nanotechnology. Twenty-five percent said they expect sales of $10 million or greater next year and a full 56 percent expect those sales levels in three years.
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In order to build those products, most executives (58 percent) said their firms plan to share facilities with universities in developing nanotechnology materials. Yet, an overwhelming percentage of respondents (77 percent) said their firms are currently developing nanotech products and processes using their own internal R&D, rather than through collaboration with universities (7 percent), suppliers (5 percent) or others.
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A majority of respondents (58 percent) utilize or plan to utilize shared use facilities at local universities; with science and engineering labs (25 percent), electronics labs (24 percent) and biotech labs (17 percent) topping the list; followed by specific diagnostic equipment (14 percent) and microfabrication labs (12 percent). Training and workforce development were not perceived as huge barriers. Seventy-six percent of executives said the lack of a knowledgeable workforce was not a significant impediment to capitalizing on the opportunities of nanotechnology. In fact, most executives rated their companies as having an excellent or very good supply of labor (61 percent), capital (58 percent), and infrastructure (58 percent) for commercializing nanotech products and processes.
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Rather, the most significant barriers to growth that were cited included lack of financing (45 percent), intellectual property issues (46 percent) and lack of available prototype facilities (43 percent).
The UMass Lowell survey team included Barry Hock, Dane Netherton, Edward March and David Kassel.
Methodology
The data summarize findings of a national telephone survey conducted from August 23, 2006 through September 19, 2006. Interviews were conducted under the supervision of a university-trained field supervisor.
A total of 407 respondents identified as business leaders in the nanotechnology industry were interviewed by telephone. The respondents’ companies were taken from a listing of Small Times Magazine nanotechnology-identified subscribers. The cooperation rate for this survey was 33 percent of the companies contacted.
Results from the total sample can be interpreted as accurate to within ±5 percent with a 95 percent level of confidence. Sub-samples have a greater margin of error.
Survey respondents were located in roughly equal proportions in each of the nation’s regional U.S. Census divisions. These regional proportions are consistent with those found in a National Science Foundation funded survey of nanotechnology leaders conducted in 2005 by the National Center for Manufacturing Sciences (NCMS) in Ann Arbor, Mich. The NCMS survey determined its geographic distribution “generally correlated well with the U.S. regions receiving the highest infusion of NNI funds and other private investments”.
Percentages may not total to 100 due to missing responses or rounding.
Tailoring particle surface chemistry with atomic precision
BY JOHN D. FeRGUSON AND JOSEPH A. SPENCER, II,ALD Nanosolutions Inc.,AND GREGory M. BERUBE AND JEFFREY D. JORDAN, Nanodynamics Inc.
Increasing miniaturization and circuit density is an ongoing trend in electronics.1 Consequently, today’s electronics generate large amounts of heat. If heat is not properly dissipated, the operational lifetime and reliability of the electronics can be drastically reduced. Therefore, effective thermal management is critical. In many applications, it is important to couple a circuit with a heatsink via a highly thermally conductive material, which is usually a composite consisting of a filler in a matrix of epoxy, paste, or grease.
Filled-epoxy manufacturers say that the higher the cured thermal conductivity, the better. The mode of material application needs to remain consistent with current standard manufacturing practices. Users cannot tolerate large changes in viscosity, temperature, or application methods without having to modify their process equipment.
Boron nitride (BN) has a very high thermal conductivity of approximately 400 W/mK at 300 K, which is much higher than other thermal filler materials such as fumed silica (SiO2, ~1.5 W/mK) and alumina (Al2O3, ~30 W/mK), and typical base epoxy matrices (~0.2 W/mK).3,4 While these properties make BN a desirable choice as a filler material in thermal management applications, the loading of BN particles in composites is limited by the inertness of the BN surface and resulting viscosity of the composite matrix. The resulting viscosity increase limits particle loading in the epoxy and therefore the composite material’s thermal conductivity. Higher loadings are needed as the microelectronics industry develops faster and denser integrated circuits that produce more heat.
 Figure 1. Schematic representation of the digital processing control provided by the self-limiting reaction sequence of two precursors. |
Ultra-thin films can alter the chemical nature of the BN surface without adversely affecting the thermal conductivity of the BN particles. Al2O3 and SiO2 are attractive coating materials because many epoxy systems have been developed and optimized for use with Al2O3 or SiO2 particles. The oxide film should be thin to minimize the effect of the coating on the thermal conductivity of the BN particles. In addition, SiO2 could be selectively deposited only on the edge planes of the platelet-style BN particles. This could allow for better alignment of the BN platelets and higher package thermal conductivity.
Wet chemical processing and chemical vapor deposition (CVD) techniques can not easily control the deposition of ultra-thin films on particles, and uneven coatings often result because of limited conductance through convoluted pathways in particle beds. CVD approaches can also cause particle agglomeration unless the particle bed is effectively agitated or fluidized. In contrast, atomic layer deposition (ALD) is an ideal technique for depositing ultra-thin films with precise thickness control and high conformality; techniques have been developed for the deposition of Al2O3 and SiO2 using sequential surface reactions.5,6 Self-limiting surface reactions control the deposition at the atomic level in this approach. Consequently, uniform and conformal deposition will occur on high-aspect-ratio porous structures or particle beds.
 Figure 2. TEM images of alumina-coated BN particulates (J.D. Ferguson et al., Thin Solid Films 371, 95 2000). |
ALD is a technique similar to CVD; however, self-limiting surface reactions are used to control the deposition of the film layer on the particle surface (Figure 1). Initially, the surface of a particle has a specific chemical functionality. The surface is then exposed to an ALD precursor (species A) that can react with that surface functionality, but not with itself. The reaction continues until all surface functional groups have been completely reacted with the precursor. At that point, species A is removed from the reactor and the surface is exposed to the second ALD precursor, species B, which will only react with the functional groups on the surface that resulted from the deposition of species A. Again, species B will continue to deposit until all active sites on the surface are functionalized to regenerate the original surface functionality, and prepare the particle for another cycle beginning with species A. Each reaction step is self-limiting, and only allows for one monolayer of the reactant to deposit. Film thickness can, therefore, be digitally controlled at the atomic scale by controlling the number of reaction cycles performed. Although ALD reaction kinetics vary depending on particle and coating chemistries, manufacture material cost is relatively insensitive due to the high-volume scale of existing fluidized bed reactor (FBR) systems. BN platelet particles are commonly used as fillers to increase the thermal conductivity of electronic plastic packages, but there are two limitations in the ability to improve performance. The first is poor surface wetting of the BN particles with the resin, which results in high viscosity and limited loadings. The second is poor interfacial adhesion of the BN particles to the polymer in the cured composite BN/epoxy matrix, which limits peel strength and thermal conductivity. Both of these limitations result from an inert BN surface that is difficult to modify by conventional CVD and wet chemical methods. A desirable designed BN filler particle maintains a high bulk thermal conductivity while the BN particle surface is controlled – but ultra-thin so as not to significantly reduce bulk thermal conductivity – to allow improved wetting and interfacial adhesion in polymer systems. The filler particle should contain Al-OH or Si-OH surface functional groups for improved wetting by polymer coupling agents/resins prior to curing, and for greater interfacial adhesion in the cured composite. Moreover, the ideal technique should provide a means to coat individual primary BN particles and not agglomerates thereof (Figure 2). In some applications, it may also be desirable to selectively coat (i.e., functionalize) only edges and not basal planes of BN particles. Such a designed filler particle may provide for increased wettability and interfacial adhesion of the BN edges within a polymer matrix while maintaining high thermal conductivity via direct BN basal plane stacking.
 Figure 3. Thermogravimetric analysis of increased oxidation resistance of 200-nm Ni particles after ALD coating with alumina (35 cycles). |
Controlling film thickness with conventional coating processes such as wet solution chemistry, physical vapor deposition (PVD), CVD, or plasma-enhanced chemical vapor deposition (PE-CVD) can be difficult. Unlike an adapted ALD technique, * these conventional processes have a tendency to agglomerate the particles and create additional particulate matter. PVD is a line-of-sight technique requiring ultra-high vacuum conditions, which works well for flat substrates but not with multidimensional structures such as particles, due to fluidization issues under high-vacuum conditions.
 Figure 4. TEM images of multi-walled CNTs before (left) and after 35 cycles of ALD coating with alumina (right). |
The general applicability of adapted ALD offers a level of process flexibility to produce customized composite particles for a variety of niche packaging applications, reducing composite design cycle time by providing engineers with a development tool to dial-in additive surface functionality while maintaining particle bulk properties. For example, an electronics packaging adhesive that requires high thermal conductivity and electrically insulating properties may incorporate BN. If the incumbent adhesive has been designed for alumina-particle additives, then alumina-coated BN of the same size will typically exhibit similar rheological characteristics, and thus lend itself to a copy-exact manufacturing strategy. Further, the electrical properties of the adhesive could be altered by replacing the BN with other similarly coated alumina particles.
This technique can also be used to impart increased oxidation resistance to metal particles in multi-layer chip capacitors (MLCCs) and low-temperature co-fired ceramic packages (LTCC).7 Base metals such as copper and nickel are used in the fabrication of MLCCs, and must be processed in an inert or reducing atmosphere to prevent oxidation. Improving the oxidation resistance of nickel, for example, allows the use of higher partial pressures of oxygen and/or higher temperatures during the organic binder burn-out phase of the MLCC firing process. This promotes complete removal of the organic and prevents the formation of carbon that may lead to defects in the resulting MLCCs. LTCCs currently use silver, gold, and other precious metals, but the ability to impart oxidation resistance to copper and nickel may allow the use of these less-expensive metals as conductors in LTCC packages.
Thermogravimetric analysis shows that one company’s** 200-nm nickel begins rapid oxidation in air at around 300°C, but after 35 cycles of alumina ALD deposition, the temperature at which rapid oxidation begins increases to more than 650°C (Figure 3). The alumina film increases the overall particle mass by just 5%, while extending the oxidation temperature by over 325°C. The oxidation protection level of the film can be tuned (within certain limits) by varying the number of ALD reaction cycles. Other performance enhancements can be obtained by using different ALD chemistries.
Carbon nanotubes (CNTs) can also be functionalized by ALD coatings. Coatings on CNTs grow in two morphologies: conformal, where the ALD film covers the entire surface of the tube but is not chemically bonded to it; and decorated, where the film is chemically bonded to the surface but grows outward only from defect sites on the tube in an island growth fashion (Figure 4). The decorated coating is of particular interest, as the alumina islands on the CNT surface may allow for better compositing with a polymer matrix, leading to products with enhanced structural, thermal, and electrical properties.
Summary
This adapted ALD is an exciting technology that provides a mechanism to engineer additive surface chemistry with atomic precision. Moreover, this approach is directly scaleable to new material sets given the maturity of FBR systems. This ability to design and cost-effectively manufacture micro- and nanoscale particles will significantly reduce composite design cycle time for an array of electronic and structural applications.
* Particle ALD
**NanoDynamics, Inc.
References
- ITRS Roadmap 2005
- Handbook of Polymer Blends and Composites, Vol. 1 – 4, C. Vasile and A.K. Kulshreshtha, Eds., 2003.
- Ng, Hsiao Yen; Lu, Xuehong; Lau, Soo Khim; “Thermal conductivity of boron nitride-filled thermoplastics: Effect of filler characteristics and composite processing conditions,” Polymer Composites, 778, 2005.
- Lee, Woong Sun; Yu, Jin; “Comparative study of thermally conductive fillers in underfill for the electronic components,” Diamond and Related Materials, 14, 1647, 2005.
- Ferguson, J.D.; Weimer, A.W.; George, S.M.; “Atomic layer deposition of ultrathin and conformal Al2O3 films on BN particles,” Thin Solid Films, 371, 95 2000.
- Ferguson, J.D.; Weimer, A.W.; George, S.M.; “Atomic layer deposition of SiO2 films on BN particles using sequential surface reactions,” Chemistry of Materials, 12, 3472. 2000.
- Base-metal Electrode-multilayer Ceramic Capacitors: Past, Present, and Future Perspectives, H. Kishi, Y. Mizuno, and H. Chazono, Jpn. J. Appl. Phys., 42, 1, 2003.
JOHN D. FERGUSON AND JOSEPH A. SPENCER, II, may be contacted at ALD NanoSolutions, Inc., 580 Burbank St., Unit 100 Broomfield, CO 80020; 716/880-1055; GREGORY M. BERUBE AND JEFFREY D. JORDAN may be contacted at NanoDynamics, Inc., 901 Fuhrmann Blvd. Buffalo, NY 14203; E-mail: [email protected].
By Richard Acello
In Scandinavian mythology, a troll is a mischievous dwarf that lives under a bridge. In modern technology, a patent troll is a company that acquires intellectual property in order to sit on the bridge between invention and commercialization and collect a toll. Or threaten a lawsuit.
While trolls like these are considered a nuisance on the path to development, others have actually enabled development by gathering the IP in a given technology, making a one stop licensing shop for developers.
Whether a company can survive on the licensing fees of the patents it holds is debatable, but there’s little doubt that holders of patents of intellectual property are crucial to the development of new technologies such as nanotechnology.
“What’s a troll?” asked John Paul, a partner at the Washington, D.C. firm of Finnegan, Henderson, Farabow, Garrett and Dunner. “I don’t think there’s a clear definition, but a popular one is an organization that is licensing patents, but is not selling products, just collecting money and not contributing to the development of technology. But the real objection is in having to pay someone.”
That’s because two companies with interesting intellectual property who are also developing or commercializing a product may be able to work out a cross-licensing deal, in which fees are reduced or dropped altogether.
Some firms that appear to be trolls may be unfairly branded, says Tim Hsieh, an intellectual property partner at Min, Hsieh, and Hack in Tyson’s Corner, Va. Hsieh points to Rambus, a company that licenses technology it has developed but is not selling in the market.
“Patent trolls are just a byproduct of the patent system,” said Hsieh. And anyway, Paul adds, a company has to have some talent in recognizing which patents are likely to pay off.
That’s why it’s difficult for a company to make a living sitting on bridges and waiting for product developers to show up.
“Long term, I don’t think licensing alone is a successful business model,” says Steve Jensen, a partner at Knobbe Martens Olson & Bear in Orange County, Calif. “Companies such as Texas Instruments and IBM have made patent licensing a successful piece of their overall businesses, but these have large portfolios. For a one-time hit, as an investor, it’s like investing in something with a kind of return I don’t expect to continue.”
That’s because patents run out, but the product itself will continue to evolve, perhaps without the technology for which the troll holds the patents.
“So you would have to continually acquire assets of value,” said Jensen.
And whether the patents have value may be a matter of timing. “Some patents don’t have a great deal of value because the market never developed around them,” Jensen added. “You have to be able to choose the development path the market is going to select and sometimes there are several paths.”
While some licensors are strictly a nuisance, others enable technology by having all the rights product developers need in one place.
“It has worked in some of the video standards, like MPEG,” said Scott Harris, a partner with Fish & Richardson in San Diego. “It developed into a standard partly for the reason that people could acquire the licenses in one place.”
Nanotechnology is such a wide open field with possible paths to so many products that experts predict there will be patents for every application an inventor can conceive. “Then there will be particular paths of each use of the technology,” Jensen said.
Another possible bonanza will be technologies that weren’t able to get off the ground, but with a nano push suddenly become doable. Take the case of a drug that couldn’t be delivered to the brain, but can with the addition of nanotechnology.
In such a case, Jensen advises filing a new patent that covers both the previously discovered drug and the nanotech delivery scheme.
Paul says a real troll is a company that files frivolous lawsuits or engages in other inappropriate behavior. On Nov. 3, a federal jury in Arizona returned a guilty verdict against patent holders Verve LLC and law firm Simon, Galasso and Frantz, which was also a defendant in the case.
“On the undisputed evidence, Mr. Galasso created a shell entity whose sole function was to suggest to patent owners that it be allowed to bring actions alleging infringement of those patents even where those owners were not aggrieved by anyone’s conduct,” said Judge Frederick Martone. That’s about as good a definition of a troll as the nanotech industry is going to get.
BINGHAMTON, NY and ATLANTA – The Packaging Research Center (PRC) at the Georgia Institute of Technology (Georgia Tech) in Atlanta is partnering with Binghamton University, NY, to develop and promote a possible industry consortium addressing thermal interface materials (TIMs). The consortium would involve OEM, IC packaging, and materials companies with academia in pre-competitive, leading-edge research.
To improve interface thermal resistance substantially (a projected 10×) the consortium would focus on thin-film materials and processes involving carbon nanotubes (CNTs) and metallics, TIM surfaces and interfaces, bonding characteristics, characterization methodologies, prototype testbeds and characterization, and TIM reliability. Especially in mobile end-products, reduced size and increased functionality generate exponentially higher amounts of heat than in previous generations. Without proficient thermal interface technology, heat could potentially cause shorts or otherwise incapacitate devices.
Six academics, three research faculty members, and six Ph.D. students from materials science and engineering (MSE), mechanical engineering (ME), and chemical engineering (ChE) disciplines will participate in the proposed consortium. A dozen industry companies have thus far expressed support. “The consortium will be fruitful in promoting mutual understanding among all participants,” noted Jin Hwang.
Interested parties may contact Chong Yoon, Ph.D.; Jin Hwang, Ph.D.; or professor Yogendra Joshi at Georgia Tech for a white paper on possible research projects and information on full (with access to intellectual property) or supply-chain membership in the 2-year, Phase 1 Industry-Academia TIM consortium program.
Albany Nanotech put another notch in its belt when it qualified its 65nm semiconductor fabrication line in September. It is the first university to qualify a line of tools that matches the current state-of-the-art in the semiconductor industry.
The line is operated under the auspices of the Center for Semiconductor Research (CSR), an industrial partnership that includes participation from IBM, Advanced Micro Devices (AMD), Sony, Toshiba, Tokyo Electron and Applied Materials. The CSR is a long-term program to develop future chip technology beginning with the 32nm node. It is intended to provide full vertical integration of the design, modeling, fabrication, testing and pilot prototyping of devices.
“The line came up really well,” said James Ryan, professor of nanoscience and vice president of technology at Albany Nanotech. “It worked pretty much on the first shot.”
Ryan and others involved in the effort say the new line is a necessity in order for Albany Nanotech to take advantage of resources like an extreme ultraviolet (EUV) alpha demo tool it took delivery of from ASML this past summer. Moreover, they say, having a full product line is critical for both developing the new processes required and for providing feedback to the tool vendors.
“We intend to totally practice the craft of device integration,” said William Rozich, IBM’s director of 300mm operations. “Toolmaker participation becomes critical.” In short, having a full line lets tool innovation become part of the design process itself.
Ryan and Rozich said the effort was a case study in making industrial teams work. “People disagree, sure,” said Ryan, “but the guy who gets listened to in the meeting is the guy in the room who is smartest on that topic.”
Rozich said the effort constituted a unique blend of cultures that was a first for IBM in another way. “It was the first time for us doing this type of thing where we are not running the show,” he said.
Nevertheless, hiccups did occur. Working “pretty much on the first shot” actually meant the second: The first, said Ryan, was a mis-process.
And the teams encountered challenges they didn’t anticipate – such as how to collaborate in an open environment while still protecting corporate assets. That may sound easy, but it’s not necessarily so when you have to balance fab viewing corridors and camera phones, or open academic networks and corporate VPNs. New protocols had to be developed.
And procurement provided an almost comic stumbling block. “Let’s just say they weren’t used to ordering the quantities (of chemicals) that we need,” said Ryan of procurement staff who were more accustomed to ordering for classroom experiments than they were for a semiconductor fab.
Going forward, the group says the line will be both integrated and modular, supporting both industrial 32nm process development as well as academic projects like one Ryan is pursuing under a Navy contract to develop a new resistor material.
“It’s a unique model,” said Alain Kaloyeros, Albany Nanotech vice president and chief administrative officer, citing the close industry-academic collaboration. “It’s important to have partners willing to take short term risk in order to be strategic.”
– David Forman
IBM unveils MEMS-based chip cooling approach
IBM researchers presented an innovative MEMS-based approach for improving the cooling of computer chips at the Power and Cooling Summit in October. Big Blue says the technique, called “high thermal conductivity interface technology,” allows a twofold improvement in heat removal over current methods and could pave the way to reduce industry’s reliance on complex and costly systems to cool chips.
The approach addresses the connection point between the hot chip and the various cooling components used today to draw the heat away, including heat sinks. Special particle-filled viscous pastes are typically applied to this interface to guarantee that chips can expand and contract owing to the thermal cycling. This paste is kept as thin as possible in order to transport heat from the chip to the cooling components efficiently. Yet, squeezing these pastes too thin between the cooling components and chip would damage or even crack the chip using conventional techniques.
Instead, the researchers used MEMS processing techniques to develop a chip cap with a network of tree-like branched channels on its surface. The pattern is designed such that when pressure is applied, the paste spreads much more evenly and the pressure remains uniform across the chip, allowing the right uniformity to be obtained with nearly two times less pressure, and a ten times better heat transport through the interface.
The technique is one of several being explored by scientists at the IBM Zurich Research Laboratory to address cooling. The researchers are also developing a novel and promising approach for water-cooling. Called direct jet impingement, it squirts water onto the back of the chip and sucks it off again in a closed system using an array of up to 50,000 tiny nozzles and a tree-like branched return architecture.
By using a closed system, there is no fear of coolant getting into the electronics. In addition, the team was able to enhance the cooling capabilities of the system by devising ways to apply it directly to the back of the chip, thereby avoiding the resistive thermal interfaces between the cooling system and the silicon.
IMEC demos feasibility of double patterning immersion litho for 32nm node
IMEC, the Leuven, Belgium, independent research center for micro and nanotech, showed in collaboration with ASML the potential of double patterning 193nm immersion lithography at 1.2NA for 32nm node Flash and logic.
The organizations said that the results prove that double patterning might be an intermediate solution before extreme ultraviolet (EUV) lithography and very high NA (beyond water) 193nm immersion lithography will be ready for production.
The results were obtained by splitting gate levels of 32nm half pitch Flash cells as well as logic cells in two complementary designs. The splitting was done automatically using software from EDA partners in IMEC’s lithography program. After splitting, both designs received optical proximity corrections (OPC) and a classical lithography approach “litho-etch-litho-etch” was performed. Exposures of both lithography steps have been carried out on an XT:1700i at ASML.
IMEC and ASML say the results show that the XT:1700i 193nm immersion tool, which has a maximum NA of 1.2, could be extended beyond the 45nm node.
Nantero announces routine use of nanotubes in production CMOS fabs
Nantero Inc., a Woburn, Mass., company using carbon nanotubes for the development of next-generation semiconductor devices, announced it has resolved the major obstacles that had been preventing carbon nanotubes from being used in mass production in semiconductor fabs.
Nanotubes are widely acknowledged to hold great promise for the future of semiconductors, but most experts had predicted it would take a decade or two before they would become a viable material. This was due to several historic obstacles that prevented their use, including a previous inability to position them reliably across entire silicon wafers and contamination previously mixed with the nanotubes that made the nanotube material incompatible with semiconductor fabs.
Nantero said it has developed a method for positioning carbon nanotubes reliably on a large scale by treating them as a fabric which can be deposited using methods such as spincoating, and then patterned using lithography and etching. The company said it has been issued patents on all the steps in the process, as well as on the article of the carbon nanotube fabric itself, U.S. Patent No. 6,706,402, “Nanotube Films and Articles,” by the U.S. Patent and Trademark Office.
The patent relates to the article of a carbon nanotube film comprised of a conductive fabric of carbon nanotubes deposited on a surface. Nantero has also developed a method for purifying carbon nanotubes to the standards required for use in a production semiconductor fab, which means consistently containing less than 25 parts per billion of any metal contamination.