AT M I
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ELECTRONIC CHEMICALS Behind the scenes, MATERIALS SUPPLIERS help make electronics faster, brighter, smaller, cheaper PUSHING THE LIMITS of the feasible
is standard in the electronics industry. Apple’s iPhone has more processing power than desktop computers did a mere 10 years ago. Relatively cheap products like the Amazon Kindle can hold a library of books. Flat-screen televisions are now larger and more brilliant than ever, yet consume less power. Better components enable the development of popular consumer items. And performance materials provided by chemical companies, in turn, enable the manufacture of these components. For chemical companies, developing new materials for electronics is becoming increasingly complex. In the memory chips that make smartphones and laptops speedy, it wasn’t long ago that the standard interconnecting material was aluminum and the dielectric insulator was silicon dioxide. Today, copper interconnects and hafniumbased dielectrics prevail. And it’s not clear what the standard dielectric material will be for the generation of memory chips that will be mass-produced in the next few years.
Even worse, materials makers don’t even know what types of memory chips their clients will be producing in 2015. As the first story in this package explains, DRAM and flash memory will still be industry mainstays. But other chip architectures are poised to enter the mainstream, primarily due to the mounting challenge of making DRAM circuitry ever smaller. Shrinking the circuitry of microchips presents difficulties in lithography. Semiconductor industry participants are
CONTENTS CHANGING MEMORIES, 10 New computer memory technologies challenge materials suppliers. DRAWING THE LINE, 14 As extreme UV technology falters, lithography industry extends an old tool. LED PRECURSOR BOOMS, 17 Trimethylgallium industry expands along with LED lighting.
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generally surprised by how much mileage they have squeezed out of 193-nm lithography, which they had expected would be outdated by now. The second story details how materials suppliers have helped extend 193-nm lithography and how they are preparing for the next generation of lithography based on extreme ultraviolet light. The future seems clearer for materials companies that supply the light-emitting diode industry. Adoption of LED lighting devices has enjoyed several growth spurts, starting with cell phones and laptops, moving to televisions, and now emerging in residential applications. The third story chronicles the scramble by materials companies to ramp up supply of trimethylgallium, which is needed to create the semiconductor at the heart of a white LED. The electronic materials market is fast paced and potentially very profitable, but it is not for the faint of heart. Spending precious research dollars on new materials that may or may not be adopted is enough to keep any R&D director up at night. ◾
M ICRO N T ECHN O LO GY
COVE R STORY
WHERE TO NOW?
Electronic materials suppliers depend on guidance from chip manufacturers to decide what products to develop next. Shown here is a Micron Technology manufacturing site.
MATERIALS ENABLE MEMORY ADVANCES Development of emerging memory architectures relies on MATERIAL INNOVATIONS JEAN-FRANÇOIS TREMBLAY, C&EN HONG KONG
tapping into even a fraction of the flash memory market would yield a market of an equivalent size,” he adds. Capturing that market, though, will require chemistry. “Currently, I would say that we are looking at two-thirds of the periodic table, if not more, for developing advanced molecules used in silicon semiconductor manufacturing processes,” says Ravi Kanjolia, chief technology officer of the performance materials producer SAFC Hitech. “We are looking at new molecules, innovative ways to produce them, new ways to test them and understand their properties and behavior on the surfaces where they are laid.” THE RISE OF MOBILE computing is
DEVELOPING PERFORMANCE materi-
als for the fast-evolving semiconductor memory market has never been simple. Every couple of years, producers need to come up with new electronic materials that enable the manufacturing of chips with ever finer circuitry. But until recently, materials suppliers at least knew which types of memory they needed to develop materials for. Today, the memory market is entering uncharted territory as chip manufacturers consider commercializing entirely new memory architectures. DRAM, the active memory of most computing devices, is becoming increasingly difficult and costly to manufacture as its circuitry gets finer. Meanwhile, both NOR and NAND flash memories, used in data storage, may be progressively supplanted by superior storage technologies. For chemical companies supplying the electronics industry, these trends translate into exciting opportunities to supply new enabling materials. But they also mean
committing to complex, risky, and costly R&D programs. Materials makers could be looking at a significant opportunity with the emergence of new memory. The global market for semiconductor materials was worth $43 billion in 2010, according to Linx Consulting, which focuses on electronic materials. The market for just one key component—high-k dielectrics—of the current generation of DRAM is worth between $80 million and $100 million, according to Jean-Marc Girard, chief technology officer at Air Liquide Electronics, which supplies chip makers with precursor chemicals that are deposited on semiconductor wafers to create thin films. “A technology using similar materials and
driving efforts to develop new types of memory. Memory is needed both for smartphones and tablet computers, as well as the huge data farms—often referred to as clouds—where users increasingly store their information. “Data farms are a bigger driver for flash memory than portable computers are,” says Weimin Li, director of deposition solutions at ATMI, a developer of advanced materials. But current memory technology is not suited for such data centers. “The power consumption of these data farms—it’s not sustainable the way the Internet is growing,” Li warns. At present, he explains, most of the information in data centers is stored in traditional, spinning hard drives that consume
“The power consumption of these data farms—it’s not sustainable the way the Internet is growing.” WWW.CEN-ONLINE.ORG
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large amounts of energy and generate much heat. DRAM is also used in vast quantities in data centers to provide fast access to data. Like the hard drives, it sucks up power because the capacitors in the chips need to be refreshed two to three times per second. This process of consistently rewriting memory generates heat as well. Replacing the hard drives and DRAM with NAND flash memory is happening in some cases, but the switch presents challenges. NAND is much slower than DRAM and less durable than traditional hard drives. Moreover, the data stored in NAND memory can be rewritten only about 100,000 times. Several technologies have emerged as contenders to challenge today’s dominant memory architectures. One of them, magnetoresistive RAM, or MRAM, is a possible replacement for DRAM in certain applications. MRAM stores data on thin-film elements in ways that resemble magnetic disks and early magnetic storage methods. But the technology still needs improvement before it replaces DRAM wholesale. “MRAM, as we understand it, is the post-DRAM,” says Yoshi Tanaka, Tokyo-based global business director for semiconductor fabrication materials at DuPont Electronics & Communications. “But it’s still early days for the technology. MRAM has a lot of catching up to do in terms of storage density to go up to the 1-gigabyte level.” Another emerging technology, phase-change memory, also known as PRAM or PCM, is a credible substitute for NAND. Making use of chalcogenide glass, the technology is similar to that of rewritable optical discs such as DVDs, but it uses electrical pulses rather than lasers to change information. PCM is already being produced by chip fabricators such as Micron Technology, which claims that it can substitute for both flash and DRAM. In the short term, flash will be easier to replace than DRAM, SAFC’s Kanjolia says. “My personal opinion is that the emerging memory will chip away at the flash market.” Meanwhile, he says, “DRAM will continue to grow.” Indeed, DRAM has a lot going for it, says Nick Pugliano, global marketing director at Dow Electronic Materials. “It’s the highest density form of random access memory on the market, it has very high endurance, and it’s very fast,” he says. For these reasons, it will occupy a central position in computing for several more years. “The jury is still out on these emerging memory technologies that are almost unproven from a manufacturing point of view,” he adds. For DRAM, by contrast, the path forward is clearer. SUPPLIERS OF ELECTRONIC materials, Pugliano points out, can
turn to the International Technology Roadmap for Semiconductors for guidance on where memory is headed. ITRS is a set of regularly updated documents produced by a consortium of semiconductor industry representatives. The road map anticipates a role for DRAM for as far out as 2026. It also provides guidance on the development of alternative memory technologies such as MRAM, according to Pugliano. Materials suppliers need all the guidance they can get because the way ahead is full of uncertainty. The near future will feature DRAM with 20- to 29-nm circuitry, which is expected to enter mass production as soon as 2015. But a lot is unknown about this generation of DRAM, such as what standard material will serve as dielectric insulator. Strontium titanate is a strong candidate offering the right properties, ATMI’s Li says. But it “is a really difficult alloy that WWW.CEN-ONLINE.ORG
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has to be made within a narrow range of compositions to get the right performance,” he says. Moreover, during manufacturing at the 20-nm scale, the dielectric must be applied uniformly in billions of holes with a 20nm opening and a depth-to-width ratio of 100:1. The technological complexity—and price—of creating such features is helping to speed up the commercial launch of new memory architectures. “DRAM still has five to 10 years, and after that, the costs will rise if we want to shrink further,” Li warns. Manufacturing new types of memory will present its own challenges. MRAM, DuPont’s Tanaka points out, uses new metal oxides and magnetic resistive layers. Part of DuPont’s job, he says, is to develop materials that will remove residues from the manufacturing process without damaging the fragile chip surface. “We have to develop new chemistries,” he says.
enjoy a dominant market share for a given type of electronic material is great. “Choosing the right target applications and collaborations can lead to early adoption,” DuPont’s Tanaka says. “A ‘process of record’ position with a leading device maker then leads to spread of the newly developed technology.” Ultimately, the success of new materi-
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quire yet other new materials, Air Liquide’s Girard says. For Resistive RAM (ReRAM), an emerging technology that resembles PCM, “the list of potentially suitable materials covers half the periodic table,” he says. Options include metal oxides such as TiO, NiO, VOx; chalcogenides like those used in PCM; colossal magnetoresistive switching materials such as (Pr,Ca)MnO3; and perovskites. Fortunately, Girard adds, the properties of most of these materials are already known. The precursors for ReRAM are largely the same ones that Air Liquide studied in the mid-1990s and early 2000s as a dielectric material in DRAM that was being considered at the time. “Our work consists more of assessing the suitability of already developed molecules than in inventing brand-new ones,” he says. “In other words, it’s dedictated application work” SAFC’s Kanjolia agrees that the materials industry is well positioned to enable the manufacturing of new memory. “We developed a fundamental understanding of phase-change memory a few years ago,” he says. “We have molecules, they are available. We’ve presented our work at conferences and published our results,” he adds. “Now it’s a matter of seeing whether these materials are moving into the mainstream or if our customers are interested to access the feasibilty of their use in their thin-film fabrication process.” And the potential for a company to
als will be tied to the types of memory that actually make it commercially, Dow’s Pugliano notes. “Substitute memory technologies are in play as options for electrical engineers to design new systems,” he says. “It’s just that now, a lot of technologies like MRAM or PCM are getting more interest because of the technical challenges we see in front of us from DRAM and flash.” ◾
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DOW C HE MI CA L
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areas not shaded by the mask are chemically altered and easily etched away with solvents. Aluminum, copper, and other materials are then deposited into the resulting grooves to form transistors and other chip features. Lithography based on 193-nm light created with an argon fluoride laser was introduced in 2004 to pattern 90-nm features. Semiconductor makers extended it without much trouble to make 65-nm features. To get to the next generation of chip, with 45-nm features, some companies introduced immersion lithography, in which the resist and the projecting lens are immersed in ultrapure water. Because water has a refractive index of 1.44, versus 1.0 for air, the effective wavelength of the light coming through the photomask is reduced to about 132 nm, and thinner lines can be drawn. Immersion technology is also used in 32-nm chips, today’s most advanced. As 193-nm lithography moved through successive chip generations, the photoresist—a methacrylate polymer decorated with various comonomers—has remained basically the same. All around it on the wafer, though, new and revamped photoresist ancillaries are finding a home. CONTROL A technician
at Dow’s technology center in Marlborough, Mass., programs a wafer sorter.
A TINY PROBLEM LITHOGRAPHY INDUSTRY extends old technique
in face of setbacks with new one
MICHAEL MCCOY, C&EN NORTHEAST NEWS BUREAU
DURING A VISIT by President Barack
Obama in February, Intel executives announced plans to build a new semiconductor facility in Chandler, Ariz. To cost more than $5 billion, the plant will be the most advanced high-volume semiconductor “fab” in the world, Intel said, making chips with features as small as 14 nm wide. For President Obama, the announcement demonstrated that American manufacturing is alive and well; for Intel, it was proof of continued technological superiority. Not in the company’s press release, though, was the fact that Intel won’t be harnessing lithography based on extreme ultraviolet (EUV) light to create those tiny features, as industry watchers had once expected. Instead, the computing giant will extend 193-nm light lithography for yet one more generation of semiconductor. Intel and its competitors are falling back on 193 nm for their most advanced chips because, despite years of effort and hundreds of millions of dollars of investment, EUV lithography isn’t ready for commercial manufacturing. Its key shortcoming is the lack of a steady, consistent light source that holds up under production conditions. Fortunately for the chip industry, researchers at electronic materials and lithography tool companies have been diligently tweaking and massaging 193-nm technology to extend it much further than
anyone had expected it could go. Yet even these scientists acknowledge that such stopgap measures are complicated, expensive, and not likely to work for much longer. “Everyone is surprised at how well 193 has done,” says Mark Thirsk, a former materials company manager who is now a managing partner with the electronic materials market research firm Linx Consulting. “It’s not desperation, but it’s creativity in a difficult situation.” Advances in semiconductor technology come in many forms, but the most critical one is arguably the shrinkage of circuitry and other features from one chip generation to another through improvements in lithography. It’s this scaling, more than any other advance, that has kept the industry true to Gordon Moore’s 1965 prediction, known as Moore’s law, that the number of transistors in a computer chip will double every two years. In lithography, a polymer-based photoresist is spun onto a silicon wafer and then patterned with light shone through a photomask imprinted with features. Resist
ONE OF THE earliest ancillary materi-
als, introduced about 15 years ago, is the bottom antireflective coating, or BARC. Containing chromophores to absorb light, BARC is applied below the photoresist to keep incident light from bouncing off the underlying silicon and degrading the surrounding undeveloped photoresist. Firmly entrenched in conventional 193-nm lithography, BARCs take on an enhanced role with immersion lithography, notes Nick Pugliano, global marketing director at Dow Electronic Materials. Instead of a single layer, BARCs for immersion are often two layers—one might be organic and the other silicon based—to minimize reflectivity in the new aqueous medium. Meanwhile, lying on top of the photoresist in advanced semiconductors is a layer
“The annual spending, and the technology challenge, is as big as putting a man on the moon.” WWW.CEN-ONLINE.ORG
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known as a topcoat or top antireflective coating (TARC). Its function, explains Ralph R. Dammel, chief technology officer at AZ Electronic Materials, is to suppress a periodic variation in light absorption known as the swing curve. Early TARCs contained perfluorooctane sulfonic acid (PFOS), which, unfortunately, was found to bioaccumulate in the environment. Working with customers, AZ created a TARC out of a tetrafluoroethylene-based polymer that doesn’t contain PFOS. The product quickly caught on. “We have a reasonable market share in BARCs, but in TARCs we are number one,” Dammel says. Indeed, TARCs and other photoresist ancillaries have become AZ’s main area of lithographic research. Dammel says the company decided five years ago to stop developing cutting-edge photoresists and to focus instead on the ancillary materials.
and valleys. An etching step removes the film at its peaks and in the valleys, leaving only “sidewalls” clinging to the resist lines. Then, etching away resist lines leaves two sidewalls that are the starting point for feature doubling. For logic chips, which boast twodimensional features not amenable to the self-aligned approach, chip makers are pur-
suing a more conservative form of multiple patterning known as litho-etch, litho-etch. It involves patterning and etching two sets of features into a silicon wafer, one after the other. It’s straightforward, Slezak says, but involved: TARC, photoresist, and two underlayers are often applied twice to create the desired pattern. JSR is a leading proponent of the third
EVEN WITH THE HELP of ancillaries, the
smallest feature size achievable with single-exposure 193-nm lithography is around 40 nm. Thus, in the absence of EUV, which has a wavelength of just 13.5 nm, the semiconductor industry has turned to yet another set of tricks to get to the 32-nm feature node and below. Known as multiple patterning, it’s a collection of techniques for doubling, tripling, or even quadrupling feature density by overlaying one lithographic pattern on top of another. JSR Micro, the electronic materials arm of Japan’s JSR, is one of the world’s leading photoresist developers. Mark Slezak, the firm’s director of lithography technology, says multiple patterning represents the confluence of the best of lithographic science with a new spirit of cooperation among photomask designers, toolmakers, and materials suppliers. “Previously, chip designers dictated the layout of the device, and we would struggle as a lithography community to meet the challenge,” he says. “Now, engineers are going to the designers, explaining their limitations with respect to physics, and working with them to optimize the layout so it is more lithography friendly.” According to Slezak, three main variations on multiple patterning have emerged. Makers of memory chips, which typically contain repetitive features, are drawn toward a technique called self-aligned double patterning. In this approach, lines of photoresist created with conventional lithography are coated with a silicon dioxide film that rises and falls over them in peaks
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plex and expensive. “Lithography at Resist is removed. 193 nm has the ability to do some pretty amazing stuff, but the costs get horrendous,” Thirsk says. “You can do 14 or 22 nm with enough tricks and tweaks, but Silicon is removed from spaces. every time you do that you add costs.” AZ and JSR, through alliances with IBM, are developing a technique called directed self-assembly, or DSA, that Silicon dioxide is removed, leaving promises to extend 193-nm lithography double pattern. even further—and with fewer process steps. In December 2010, AZ and IBM announced an agreement to develop SOURCES: Wikipedia, IEEE self-assembling block copolymers for use in DSA. Then in March, at SPIE’s Advanced Lithography 2011 conference, JSR and IBM presented a paper on a three-year-old research agreement to develop DSA based on a special polymer blend rather than block copolymers. At Dow, Pugliano expresses interest in DSA but has a wait-and-see attitude. As a major plastics manufacturer, Dow has plenty of experience with polymer self-assembly, he notes. But Dow is looking ahead to EUV and focusing on improving the photospeed, resolving power, and pattern fidelity of photoresists that will work in EUV light. Unlike the relatively pure 193-nm light that comes out of an argon fluoride laser, Pugliano notes, the 13.5-nm light, created by firing a CO2 laser at drops of tin, is spectrally impure. “Making the resist particularly sensitive to the 13.5-nm EUV photon while spectrally filtering the longer wavelength radiation is a key piece of photochemistry the industry is working on,” he says. The resists that might be able to do this, experts say, include known photopolymers such as polyhydroxystyrene and methacrylates, as well as newer fluorinated polymers, molecular glasses, and nanoparticles. “All of these are still on the table,” JSR’s Slezak says. They are on the table because EUV lithography continues to evolve. To date, only a handful of preproduction-strength EUV tools have been shipped to customers. Back in EUV development labs, engineers are still struggling to fine-tune the light source, ramp up power levels, and improve consistency and reliability. Yet given the investments that have been made and the lack of alternatives for continuing to advance Moore’s law, most in the electronic materials sector are betting on EUV. “This is big science. The annual spending, and the technology challenge, is as big as putting a man on the moon,” Pugliano says. “It’s really hard stuff, but I believe it will succeed.” ◾
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SHU T T ERSTO CK
COVE R STORY SPOTLIGHT
LED lighting is a new frontier for trimethylgallium.
The second cycle, Anwar says, began about 18 months ago with the introduction of LED-backlit flat-panel TVs. LEDs offer a number of advantages over the CFLs that TV makers used for many years: They consume less power and last longer than CFL bulbs, and their compactness makes thinner TVs possible. Moreover, LEDs can be controlled better than CFLs, allowing light to be directed where it is needed on the screen. This makes for more vivid colors and better contrast ratios. THE WAVE OF TV growth has challenged
BRIGHT OUTLOOK FOR LED PRECURSOR Large new applications are behind boom in the TRIMETHYLGALLIUM business ALEXANDER H. TULLO, C&EN NORTHEAST NEWS BUREAU
THE CHANGES MAY be hard to notice,
but light-emitting diodes are creeping into our daily lives. Thanks in part to LEDs, laptop batteries last longer between charges than they did a few years ago. LEDs permit the newest television models to be thinner and brighter than older ones. And white LED bulbs are starting to appear in the lighting departments of retailers such as the Home Depot. For producers of a critical LED raw material, trimethylgallium (TMG), the changes haven’t been so subtle. To stave off shortages, they are planning to add capacity well before they’ve completed earlier projects. Major producers including AkzoNobel, Dow Chemical, and SigmaAldrich’s SAFC Hitech unit all have undertaken multiple expansions over the past year. Chemtura is entering the market through a Korean joint venture. TMG is a precursor used in chemical vapor deposition chambers to lay down layers of elemental gallium for compound semiconductors like gallium nitride and indium gallium nitride. These semiconductors are used in blue LEDs, which are coated with phosphors to make them emit white light.
TMG is also a precursor for gallium arsenide (GaAs) semiconductors that end up in lasers, photovoltaic cells, and telecommunication devices. LEDs have spurred the precursor’s enormous growth over the past few years—25 to 30% annually by most accounts. Asif Anwar, director of the GaAs and compound semiconductor service at the consulting group Strategy Analytics, forecasts that the LED market will grow at an annual clip of 22% through 2014, at which time it will reach $19 billion. Raw materials such as TMG and the sapphire wafer substrates to which the precursors are applied will grow at a similar rate, he says. LED growth has occurred in several phases, Anwar explains, beginning with the use of LED backlights to illuminate cell phones, laptops, and other small devices. Today, nearly all of these gadgets use LED backlights instead of compact fluorescent lights (CFLs).
the TMG industry to keep up. “Companies like Samsung brought out their LED televisions with a very rapid manufacturing ramp-up,” says Geoff Irvine, vice president of business development at SAFC Hitech. “The market took off in terms of demand, and there was a shortage of TMG and sapphire substrates.” Although they sometimes seem ubiquitous, LEDs command only 30 to 40% of the world TV market, according to Michiel Floor, global business manager for highpurity metal organics at AkzoNobel. “So there is a way to go in terms of growth potential in the TV market,” he says. The third cycle of LED growth will be the adoption of LED lighting for residential use, Anwar says. This market is largely the result of legislation. A U.S. phaseout of conventional incandescent lightbulbs will begin next January with the ban of the 100- W bulb. Many countries around the world have similar plans. LEDs will vie with CFLs for the enormous lighting market that is up for grabs. LEDs are somewhat more energy efficient than CFLs, and they last about 50,000 hours, versus 10,000 hours for CFLs. But LEDs are expensive. A recent C&EN check of the Home Depot found 40-W-equivalent LED bulbs on sale for about $18 each. Comparable fluorescents were on sale for about $1.00 each. To capture more of the lighting market, Anwar says, LED makers must bring costs down to a “more manageable level” by scaling up manufacturing. Luckily, the industry is already doing so because of TV demand. LED makers have been borrowing methods from computer semiconductor makers, observes Joe Reiser, global business director for metal-
LEDs will vie with CFLs for the enormous lighting market that is up for grabs.
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organic technologies at Dow Chemical. “As the industry matures, we see more of a larger scale manufacturing mentality akin to what we see in the semiconductor world,” he says. “The parallels are pretty striking.” For example, LED makers have been processing bigger and bigger wafers, much as semiconductor chip makers have done. By increasing wafer size, they can cram more usable LED chips onto each wafer. Already, the LED industry has moved from 2-inch wafers to 4-inch wafers, Anwar says, and is transitioning to 6-inch wafers, which he expects will be mainstream by 2014. TMG producers are doing their part to scale up with LED makers. AkzoNobel’s recent experience illustrates how challenging it has been to keep pace. AkzoNobel doubled TMG capacity at its La Porte, Texas, plant in June 2010. It did so again this past January. “We are sold out again, which is amazing,” Floor says, noting the company is now adding incremental capacity at the site. THE COMPANY IS also planning an en-
tirely new TMG plant in La Porte. It will be three times the size of its recently expanded plant, giving Akzo more than 100 metric tons of total gallium-based metal-organic capacity per year and making the company, Floor claims, the TMG market leader. Although most LEDs are made in Asia, Floor says Akzo chose to build the new plant in La Porte because “it was the fastest way for us to make this happen.” Akzo already has infrastructure in place for handling
TMG, a hazardous pyrophoric chemical. In addition, Akzo, along with Chemtura and Albemarle, is a major supplier of trimethylaluminum (TMA), used to synthesize both TMG and methylaluminoxane, a cocatalyst for metallocene polyolefin catalysts. Akzo makes TMA in La Porte. That back-integration is an important advantage, Floor says, especially now, because TMA also is in short supply. Akzo’s heritage, he notes, is “completely different” from any of its competitors’. The heritage, however, will soon be less atypical. Earlier this year Chemtura and South Korea’s UP Chemical formed a joint venture, DayStar Materials, that intends to have TMG and TMA capacity in Korea running by the end of this year. Chemtura has also been explanding capacity for TMA and another organometallic precursor, diethylzinc, at its plant in Bergkamen, Germany. The industry’s other TMG suppliers are electronic chemicals firms that offer the precursor as part of a stable of products for the semiconductor industry. Dow got into the business through its 2009 acquisition of Rohm and Haas. SAFC did so through Sigma-Aldrich’s 2007 purchase of Epichem. Both Dow and SAFC are also investing heavily in TMG. As shortages loomed last year, Dow announced a multipronged approach to expand capacity by 60 metric tons per year. The company boosted existing operations at its North Andover, Mass., plant and slated new capacity at the site. In addition, plans called for a new plant in Cheonan, South Korea.
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Behind the scenes, however, Dow also built a new TMG plant at its massive flagship site in Freeport, Texas. “In Freeport, we have the infrastructure in place where we can add capacity in a much faster timeline than we would have traditionally,” Dow’s Reiser says, noting that the project was conceived in June 2010 and completed in November. The infrastructure in Freeport was the key. The site handles a lot of TMA because of Dow’s extensive polyethylene operations there. The scale of the new plant is an order of magnitude larger than what Rohm and Haas would have been able to build on its own, he says. Original plans called for the equipment in Freeport to be moved to South Korea. However, Dow ended up building an entirely new plant there and will leave the assets in Freeport in place to run as needed. SAFC has also engaged in multiple expansions. Last year, the company invested $2 million to add capacity at its TMG facility in Bromborough, England. In addition, the company is building a new plant in Kaohsiung, Taiwan, that it expects to complete later this year. Despite the flurry of expansions, suppliers aren’t concerned about TMG capacity getting too far ahead of demand. “The growth rate of LEDs has essentially doubled the size of the market every two-anda-half years,” SAFC’s Irvine says. “With those kinds of growth rates, it will take only a little while to bring supply and demand back into balance.” ◾
