A thin-film thermoelectric cooler works like a solid-state heat pump for cooling hot spots on ICs. The eTEC film, from Nextreme Thermal Solutions, Research Triangle Park, N.C. (nextreme.com) is manufactured using semiconductor processing techniques. “The thermal films are small, efficient, and reliable, adding just 100 microns of height to a heat spreader,” says Nextreme VP Paul A. Magill. “It responds in milliseconds to rapidly cool or heat to maintain a precise temperature.” The device pumps up to 150 W/cm² with some designs delivering as much as 400 W/cm,² versus less than 10 to 20 W/cm² for competitive devices.

The eTEC operates on the Peltier effect: Driving an electric current through a circuit containing two dissimilar materials absorbs heat at one junction — the cold side — and releases it at the other junction — the hot side. ETEC is built with thin-film semiconductor materials that have high electrical conductivity to maximize current flow and poor thermal conductivity to minimize heat flow from the hot side to the cold side.