Copper inverse opal composite wicking structures for high-performance thermal management in compact electronic devices

With the continuous development of electronic devices toward higher performance, higher integration, and miniaturization, ultra-thin vapor chambers (UTVCs) have been increasingly widely used in efficient thermal management of confined spaces. However, in extremely thin spaces, the wicking structure has become a key factor restricting the further performance breakthrough of UTVCs. To address this challenge, this study proposes a novel wicking structure based on copper inverse opal (CIO), which significantly enhances capillary performance without increasing thickness. The mesh with copper inverse opal (MCIO) prepared by this process exhibits a capillary coefficient of 18.96 mm·s^−0.5, which is 85.9% and 534.1% higher than that of the traditional wicking structure and the inverse opal (IO) structure, respectively. Furthermore, the thickness of the UTVC integrated with the MCIO wicking structure is only 0.29 mm. Experimental investigations reveal that the optimal filling ratio of this UTVC is 40%. Under this filling ratio and an inclination angle of 90°, the UTVC achieves a maximum heat load of 6 W, a minimum total thermal resistance of only 0.85 °C/W, and a maximum effective thermal conductivity of 13,707.57 W/(m·K). The maximum effective thermal conductivity of the MCIO-UTVC sample reaches approximately 206.5% of that recorded for the baseline M-UTVC. In addition, the infrared experimental results show that compared with the solid copper plate, the UTVC exhibits excellent heat dissipation performance and temperature uniformity. The research results indicate that the copper inverse opal composite process has great potential in enhancing the heat transfer performance of ultra-thin phase-change heat transfer devices.