Immersion Phase-Change Liquid Cooling Devices Based on Copper Microgroove/Nanocone Composite Structure.

Along with the rapid development of the digital economy and artificial intelligence, heat sinks available for immersion phase-change liquid cooling (IPCLC) of chips are facing huge challenges. Here, we design a high-performance IPCLC heat sink based on a copper microgroove/nanocone (MGNC) composite structure. Maximal heat fluxes (qmax) of the MGNC structure, microgroove structure, and flat copper reach 112.7, 88.0, and 24.0 W·cm-2 as the surface temperature (TS) of the simulated chip heat source rises up to 85 °C, respectively. As compared to the flat copper, the nanocone structure shows much higher cooling efficacy but lower cooling capacity, with qmax = 19.8 W·cm-2 at TS = 69.8 °C. Structure-performance relationships are rationalized by combined experiments and theoretical analyses. This work not only helps deeply understand the respective roles of microscale and/or nanoscale structures in IPCLC but also provides the state-of-the-art solution with the best IPCLC performance as compared to all peers' reports.