MII Tackles Patterned Media Opportunity
David Lammers, News Editor -- Semiconductor International, 5/22/2008 9:26:00 AM
Imprint lithography vendors have found a market that could propel revenues and help fund technology development aimed at the larger cutting-edge CMOS opportunity. Discrete track recording (DTR), a technology the hard disk drive (HDD) industry has been talking about for the past decade, will enter the pilot production stage soon, providing vendors of nanoimprint lithography (NIL) with a market that is expected to total hundreds of imprint tools. The HDD opportunity is already turning into revenue for NIL vendors.
Molecular Imprints Inc. (MII, Austin, Texas) has received multiple orders for its newly developed Imprio 2200 system, aimed at pilot production of HDD media, said Paul Hofemann, vice president of marketing and business development for emerging markets at MII.
Obducat AB (Malmo, Sweden) has received an order for its production-worthy “Sindre HDD” imprint tool from an unnamed HDD media supplier, as well as several other R&D-level tools, said Patrik Lundström, the CEO of Obducat.
While much of the attention paid to the imprint lithography field has been on efforts to conquer leading-edge CMOS, DTR and, later, patterned media are “a pretty sizable market,” said Ken Rygler, chief marketing officer at MII. With an annual production of a billion disks or more, and each imprint system able to produce ~500 disks per hour, Rygler said, “That nets out to hundreds of machines.”
The HDD industry has managed to double the aerial bit density every year, largely by improving the read-write heads with giant magneto-resistive (GMR) technology. Recently, the HDD industry adopted perpendicular recording using bits that can be placed more closely together than horizontal recording.
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| HDD vendors will use NIL to create magnetic pillars on the media. |
To meet the needs of the HDD industry, MII developed the Imprio 2200 machine with two print modules to pattern on both sides of the disks. It has a throughput of 180 disks per hour. While the tools aimed at CMOS must perform step-and-flash exposures, with particular attention paid to alignment, the Imprio 2200 patterns the entire disk at once using a 1:1 template the size of the disk itself.
While overlay is not a major issue, throughput and cost are the market drivers for customers making hard drive media. Particles are another concern. Hofemann said the monomer liquid must dispense and fill very quickly with “no excess liquid pushed off the side that could cause particles.” MII now claims 100 granted patents, with ~200 more applied for, including IP on how to deal with bubbles.
The Imprio 2200 creates the monomer drop pattern by employing the same GDSII file used to create the pattern on the media, Rygler said. Also, MII has developed technology that creates an adhesion layer on top of the substrate that allows the monomer to spread out faster and more evenly.
Comparing it to making a pancake, Rygler said the goal is to use droplets of a size and quantity needed to spread out to fill the template and no more. That involves controlling the drop pattern and surface tension so that the liquid forms as a flat layer.
“We reduce the fill time by using a low-viscosity fluid and create an environment with our proprietary IP, which is not friendly to bubbles. The monomer absorbs bubbles quickly — the bubbles are held captive in the liquid,” Hofemann said.
Rygler said the bit density required for patterned media is an ideal fit for imprint lithography. “The HDD companies are talking about 10 trillion bits with 12-20 nm pillars on a patterned disk. For the discrete track recording, the tracks will have a 0.5 nm pitch to begin with.
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| Patterned media will take over the HDD market quickly, according to forecasts by Coughlin Associates. |
“With CMOS, the contacts are the most difficult patterns with 60-70 nm contacts for the 45 nm technology. We think forming these 20 nm pillars will provide learning that will come in handy for the contacts.”
Hofemann said, “Patterned media is a huge transition for the HDD industry. The first adoption will be in mobile for the 65 mm disks. By 2009, the HDD industry wants each disk to hold 1000 Gb of data, which is one terabit. They know they will soon run out of the different tricks used to increase the aerial density with the unpatterned substrates. That is the reason why patterned media will come in, because everybody wants to stay on this track of 100% annual increases in aerial density.”
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| Doubling the aerial density of HDD media annually is driving vendors to discrete track recording and patterned media. |
Notebook computer HDDs have a single platter, while drives used in servers can have six or seven disks. With patterned media as a new technology, HDD vendors will apply it first to mobile systems that have less critical data reliability standards than the servers used in banks, he said.
The $40B HDD industry spends ~$4B annually in capital equipment. Hofemann said HDD and media suppliers will engage in pilot production this year and next year, then move on to volume production. By 2011, forecasts call for 1.2 billion disks to be patterned on both sides, taking up more area than all of the silicon wafers used in that year.
HDD media companies estimate that each patterned disk will start out costing ~$8 and then move down to $6 as throughputs increase. Patterned media may add ~$2 per disk to the media production costs, with imprint and etch systems as the major tools required. MII believes its cost per disk is already <50 cents. Hofemann said the disk production lines today can make 800-1000 disks per hour. The media makers want the imprint tools to keep up, with each imprint tool eventually printing 800-1000 disks per hour.
MII has placed five of the R&D-level Imprio 1100 tools at three HDD companies, with a rated throughput of 60 single-sided disks per hour. The Imprio 2200, aimed at pilot production lines, is rated at 180 double-sided disks per hour. Hitachi Global Storage Technologies (San Jose) has ordered one Imprio 2200 for its development center, with delivery scheduled for later this year. Another order is in-hand for a major customer that cannot be named.
Hofemann said getting to 1000 disks per hour will require making improvements to the disk handling and system control systems, reducing the size of the print modules and putting more print modules in each system. “The 2200 can do 180 double-sided disks, and we have demonstrated internally we can do much more than that. There is a lot of unused real estate inside the box. We can make the module half the size and eliminate other inefficiencies of the current design. Just by clustering the modules, we can scale up. We know we can get 350-700 disks per hour with four modules,” Hofemann said. The result is that MII will need to grow quickly. With ~95 employees now, hiring is on pace to add ~10 employees a month. Earlier this month, the company announced additional venture funding of $12.9M. While tools are now made by technicians at MII’s facility in Austin, volume tool production will be shared with contract manufacturers. Rygler said the investor list includes Dai Nippon Printing Co. (Tokyo), KLA-Tencor Corp. (San Jose) and Tokyo Electron Ltd. (TEL, Tokyo), all of which have expertise at tool manufacturing that will prove valuable to MII as it seeks to boost throughput for patterned media production.
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| MII makes the Imprio 2200 at its Austin facility now, and plans to add contract manufacturers when volumes ramp. |
“That is what the HDD and media companies want to find out,” Hofemann said. “They want to know how we are going to manufacture these tools by the hundreds. They want to know if they select us, what is our strategy to make lots of tools?” He said ~10 pilot and early production lines are being created for DTR media production.
Each disk must undergo imprint, etch, de-scum, inspection and planarization steps. The etch and ion milling vendors also have some development work to do, Hofemann said, arguing that imprint technology development is ahead of the reactive ion etch (RIE) and milling solution providers, which are working to increase the speed of the etch steps.
Hofemann, who came to MII four months ago from Veeco Instruments Inc. (Plainview, N.Y.), said he was surprised at how little fluid is required to imprint the HDD disks. “Over six months in high volume, this machine can use a couple of liters of fluid. The customers don’t need a resist tank sitting next to their imprint tool, they can have something the size of a large soft drink bottle. There is no ancillary equipment, no track, required. We are talking about picoliters of fluid for each disk.”
MII is working with two of the major mask vendors to create the HDD media templates. At last week’s Sematech Litho Forum at Bolton Landing, N.Y., MII co-founder S.V. Sreenivasan spoke of the HDD opportunity facing MII and said it will provide a means of improving the imprint template infrastructure.
“The HDD vendors are talking about 12 nm pillars in order to get terabit-per-square-inch density levels. That is very viable for us. With one billion hard disks per year, it gives us a means of developing the mask infrastructure and learning how to support customers 24/7,” he said.
That knowledge will prove valuable as MII attacks the larger CMOS opportunity, where optical scanner vendors gain ~$7B in annual revenues, Rygler said, noting that MII expects to exceed $20M in revenues this year, up from ~$13M in 2007. The company was founded in 2001 as a spin-out from the University of Texas, where co-founders Grant Willson and Sreenivasan are professors.
