Heatsinks are a staple of PC cooling technology as we know it. Both passive and active coolers make use of heatspreaders and heatsinks, but a team of researchers from the University of Illinois at Urbana-Champaign and the University of California, Berkeley (UC Berkeley) recently found what looks like a far better, all-encompassing, and sleeker solution.
The researchers describe their experiments and findings in a paper (opens in new tab) entitled "High-efficiency cooling via the monolithic integration of copper on electronic devices," as spotted by Science Daily. Highlights of the new copper conformal coating technology are that it takes up little in the way of physical space in a device and that it is much more efficient than current copper heatsinks. The researchers demonstrated a 740% increase in the power per unit volume.
There are three main issues with conventional heatsinks, explained Tarek Gebrael, the lead author of the paper and a UIUC Ph.D. student in mechanical engineering. First, the most advanced heatsinks using exotic and highly efficient conducting materials can be expensive and difficult to scale up. Gebrael mentioned heatspreaders containing diamonds as one rival tech, clearly illustrating his point.
Secondly, conventional designs combine a heatspreader and heatsink in tandem, and "in many cases, most of the heat is generated underneath the electronic device," lamented Gebrael. Thirdly, the best heat spreaders can't be installed directly onto electronics but require a thermal interface material, inhibiting optimal performance.
So, how does the new technology address all the above drawbacks of current heat sinking methods? The new heatsink coating covers the entire device, creating a large cooling surface area.
"The approach first coats the devices with an electrical insulating layer of poly(2-chloro-p-xylylene) (parylene C) and then a conformal coating of copper," says the research paper. "This allows the copper to be in close proximity to the heat-generating elements, eliminating the need for thermal interface materials and providing improved cooling performance compared with existing technologies."
This coating technique does away with any large outcrops of copper or aluminum, so it is a much more compact solution to wick heat away from fast-running processors and memory. According to the researchers, the thin conformal coating and lack of a bulky traditional heatsink deliver a much higher power per unit volume, up to 740% better. "You can stack many more printed circuit boards in the same volume when you are using our coating, compared to if you are using conventional liquid- or air-cooled heat sinks," asserted Gebrael.
The researchers next plan to verify the coating's durability, which is an important step to industry acceptance. Additionally, the researchers plan to test with immersion cooling and in high voltage environments. For their initial tests, the researchers used "simple" PCBs, but they hope to scale up testing of the cooling tech on hotter running electronics like "full-scale power modules and GPU cards."
In summary, the technology sounds promising without being too expensive or complicated for component makers to consider for practical use. Until this new heat sinking tech arrives, you will have to contend with conventional CPU cooling and GPU cooling.