Researchers from the University of Illinois at Urbana-Champaign have developed a novel new “heat switch” for technology that allows users to turn heat flows “on” or off”.
The research study, which was published as “Millimeter-scale liquid metal droplet thermal switch” in the journal Applied Physics Letters, describes a heat switch that may have massive implications in the field of electronics due to the ability to improve device performance reliability.
According to William King, the Andersen Chair Professor in the Department of Mechanical Science and Engineering and the project co-leader, “heat flow occurs whenever you have a region of higher temperature near a region of lower temperature…In order to control the heat flow, we engineered a specific heat flow path between the hot region and cold region, and then created a way to break the heat flow path when desired.”
Nenad Miljkovic, the other co-leader on the project an Assistant Professor in the Department of Mechanical Science and Engineering, expanded on the process, stating that “The technology is based on the motion of a liquid metal droplet…The metal droplet can be positioned to connect a heat flow path, or moved away from the heat flow path in order to limit the heat flow.”
The concept was put into action in a system that was modeled after modern electronics system – showing the potential of such a heat switch in the devices we use each and every day. One one side of the switch there was a heat source that was meant to represent the power component, with the other side holding liquid cooling for heat removal. When the heat switch was on, the team managed to extract heat at more than 10 W/cm2, but as soon as the heat flow was turned off they saw a drop by nearly 100X.
King and Miljkovic were joined by several other authors on the paper, including Paul Braun, Racheff Professor of Materials Science and Engineer and the Director of Materials Research Laboratory, as well as graduate students Tianyu Yang, Beomjin Kwon, and Patricia B. Weisensee from the mechanical science and engineering department and Jin Gu Kang and Xuejiao Li from materials science and engineering.
While the discovery of a heat switch is an exciting occurrence, it only marks the beginning of further research into how exactly this new development can be applied to enhance and improve electronics moving forward. King says that “the next step for the research is to integrate the switch with power electronics on a circuit board.” The heat switch for electronics is in its infancy, and the researchers plan to have a working prototype that can be applied on a wider scale later this year.
As electronics continue to develop, one problem that we continue to deal with is the heat that the technology gives off. With a new heat switch, manufacturers will be able to move forward with advancements that weren’t possible before due to cooling limitations.