Cooling chips down

Russ Arensman -- 2/1/2005
Electronic Business

Semiconductor makers have been struggling to find ways to cool their increasingly powerful chips. Intel's recent cancellation of a 4-gigahertz Pentium 4 processor that might have turned PCs into toaster ovens was a sign that they may be losing the battle.

Intel isn't the only one having problems. Apple Computer added expensive liquid-cooling systems to its G5 computers last year to chill their IBM processors. Graphics and HDTV image processors are running so hot that they soon may require similar cooling strategies.

The problem is an old one, caused by increasing numbers of circuits' being packed into chips. But as circuit dimensions shrink into the nano realm, transistors and capacitors are leaking increasing amounts of electrons, causing the chips to both heat up and consume more power.

Help may be on the way, however, from a new crop of startup companies developing novel heat-reduction technologies. Companies such as Cool Chips, Cooligy, iCurie, NanoCoolers and Thorrn Micro Technologies are pursuing multiple approaches, from new ways of circulating liquids or air to remove heat, to variations on semiconductor technology. Venture capitalists are backing several of the companies, whose first products should be available in 2005.

In a recent report, research firm Business Communications Co. (BCC) forecasts that the world market for current electronics thermal-management products will grow from $3.3 billion in 2003 to $5.9 billion by 2008, with the largest market segment-computers-expanding from $1.3 billion to $2.3 billion.

Yet current approaches can remove only limited amounts of heat. The new cooling companies claim that their technologies will be more effective, although usually at a somewhat higher cost. NanoMarkets, a nanotechnology research firm, estimates that these new-generation cooling technologies may capture $417 million in sales by 2011.

Cooligy and NanoCoolers appear to have the strongest financial backing, having raised more than $50 million in venture funds between them. Both plan to introduce different kinds of liquid-cooling systems this year.

Cooligy, founded by some Stanford University professors with funding from several prominent venture capitalists, plans to dissipate heat by circulating water through silicon microchannel heat collectors. Andy Keane, Cooligy's vice president of marketing, says, "The real magic we focus on is the microchannels," which maximize the surface area for cooling. The company has also developed solid-state electrokinetic pumps that circulate water without moving parts.

NanoCoolers, founded by a former IBM researcher, uses magnetic pumps to circulate a nontoxic liquid metal gallium alloy, which the company claims absorbs and releases heat far more efficiently than water.

The company also is developing improved thin-film thermoelectric coolers that can be used to cool lasers, disk drive heads and image sensors. Thermoelectric coolers are a time-tested, albeit power-hungry, technology that cools by absorbing heat on one side of a semiconductor and releasing it on the other side. NanoCoolers plans to make them more efficient and less costly. Says Bob Mayer, the company's vice president of marketing, "We think we can increase the power efficiency by changing the design and some of the materials used."

ICurie, founded by a former Samsung and NASA scientist, has developed a pumpless system that circulates water through microchannels that can be etched into plastic, ceramic or metal heat collectors. The company has a manufacturing deal with Taiwan's Asia Vital Components (AVC), one of the largest makers of PC cooling components, and has been testing its products with Advanced Micro Devices, Acer and LG Electronics.

Cool Chips reportedly plans to use quantum electron tunneling to cool waferlike devices consisting of electrodes separated by a 10-nanometer gap. This technique removes heat from one side of the wafer, by allowing electrons to cross over into a heat sink but not to cross back.

Thorrn Micro, a recent Purdue University spinoff, is developing tiny air pumps to remove heat. This technology uses electrical sparks between carbon nanotube electrodes to ionize the surrounding air, resulting in air flows from air pumps that the developers claim can be as powerful as conventional electric fans but potentially smaller and less costly.

Still to be seen, though, is whether any of these new technologies will be effective and affordable enough to generate significant sales. "They're going to have to demonstrate a real price/performance advantage," says NanoMarkets analyst Lawrence Gasman.

Yet, considering the industry's increasing heat problems, there's little doubt a potential market exists. Analyst JoAnne Feeney, with investment research firm Punk Ziegal & Co., says chip makers may temporarily solve their heat problems by using multiple lower-power processors and developing better insulating materials to reduce electron leakage. But problems will inevitably recur as they move to newer generations of even smaller circuits. "There's certainly going to be a long-term demand for the dissipation of heat," she says.