Dancing Droplets Cool Hotspots in High-Performance Electronics

Engineers from Duke University have developed a technology to cool hotspots in high-performance electronics using the same physical phenomenon that cleans the wings of cicadas. When water droplets merge, the reduction in surface area causes the release of a small amount of energy. So long as the surface beneath is hydrophobic enough to repel water, this energy is sufficient to make the merged droplet jump away. On the wings of cicadas, this phenomenon drives droplets to catch and remove particles of dirt and debris. In the new cooling technology, droplets jump toward hotspots to bring cooling where the electronics need it most. The new technology relies on a vapor chamber made of a super-hydrophobic floor with a sponge-like ceiling. When placed beneath operating electronics, moisture trapped in the ceiling vaporizes beneath emerging hotspots. The vapor escapes toward the floor, taking heat away from the electronics along with it.

Transcript

00:00:08 A cicada's wings stay clean through droplets of water that jump off their surface all on their own, taking bits of dirt with them. If a surface is hydrophobic enough this happens naturally when water droplets merge. Now, Duke University researchers are using this phenomenon to cool electronics. As hotspots develop, they vaporize water trapped in a sponge-like layer directly beneath the circuits. The vaporized water disperses, accumulating into droplets on a superhydrophobic floor that whisks away the heat. As the droplets cool and merge, they jump off the surface and back underneath any hotspots and, the process repeats.

00:00:40 The new technology carries away heat from high performance electronics vertically as well as horizontally, which gives it an advantage over traditional methods.