New thermal management technology for electronic devices reduces bulk while improving cooling — ScienceDaily
Electronic devices generate heat, and that heat must dissipate. Failure to do so may result in high temperatures compromising the operation of the device or even damaging the device and its surroundings.
Now, a team from UIUC and UC Berkeley have published an article on Nature electronics detailing a new method of cooling that offers a large number of advantages, among which the least important is the efficiency of the space that offers a substantial increase over conventional approaches in the power of devices per unit volume.
Tarek Gebrael, UIUC Senior Author and PhD. mechanical engineering student, explains that existing solutions suffer from three shortcomings. “First of all, they can be expensive and difficult to expand,” he says. Heat sinks made of diamond, for example, are sometimes used at the chip level, but they are not cheap.
Second, conventional approaches to heat dissipation generally require that the heat sink and a heat sink, a device for efficiently dissipating heat, to which the spreader directs heat, be connected to the heat sink. top of the electronic device. Unfortunately, “in many cases most of the heat is generated under the electronic device “, which means that the cooling mechanism is not where it should be for optimal performance.
Third, state-of-the-art heat sinks cannot be installed directly on the surface of the electronics; a layer of “thermal interface material” should be placed between them to ensure good contact. However, due to its poor heat transfer characteristics, this middle layer also introduces a negative impact on thermal performance.
The new solution addresses these three issues.
First of all, the primary material used is copper, which is relatively inexpensive. Second, the copper coating completely “swallows” the device, says Gebrael, “covering the top, bottom, and sides … a conformal coating that covers all exposed surfaces,” so there is no heat-producing regions. careless. Third, there is no need for a thermal interface material; the copper heat sink device and diffuser are essentially one-piece. Plus, you don’t need a heat sink.
“In our study, we compared our coatings to standard methods of heat sinking,” says Gebrael. “What we’ve shown is that you can get very similar thermal performance, or even better performance, with coatings compared to heatsinks.” However, one device that uses the new solution is dramatically smaller than one that uses heatsinks, which are bulky. “And that translates into a lot more power per unit volume. We’ve been able to show a 740% increase in power per unit volume.”
This makes a big difference in the real world. “Let’s say you have multiple printed circuit boards,” Gebrael says. “You can stack many more printed circuit boards in the same volume when using our coating, compared to using conventional liquid or air cooled heatsinks.”
Co-author Nenad Miljkovic, an associate professor of mechanical science and engineering at the UIUC and an advisor to Gebrael, says: “This technology combines two separate approaches to thermal management: device-level cooling and heat dissipation Tarek’s work in collaboration with the UC Berkeley team has allowed us to use an open-ended approach to the development of unenclosed electro-thermo-mechanical technology to develop a solution to a difficult problem for multiple industries. “
Miljkovic says the team continues to expand the work, which is funded in part by ARPA-E and POETS NSF ERC at the UIUC.
They are still investigating the reliability and durability of coatings, which are critical to industry acceptance. The document already showed that coatings can be used in both air and water, the latter being necessary for “immersion cooling” applications. The team is now looking for reliability in boiling water, boiling dielectric fluids and high voltage environments. They will also implement the coatings on large-scale power modules and GPUs, while only using simple test boards in the initial work.
These ongoing efforts should bring the new solution a major step toward the transition to industry and commercial production for a variety of applications, including power electronics cooling, data center thermal management, and refrigeration of electrical machines.