Recent advances in micro/nano-structured heat pipes

The development of high-performance and high-density packaging electronic devices has led to the concentration of heat generation in smaller areas, resulting in the formation of "hotspots", i.e., regions of high heat flux. Localized high temperatures can adversely affect the performance of electronic components or cause high thermal stress. Therefore, there is an urgent need to develop thin, high-performance cooling devices that can achieve effective heat dissipation in confined spaces. Micro/nano-fabrication technologies offer solutions to address these challenges. Heat pipes, as efficient passive cooling devices, are widely used for heat dissipation in various electronic devices. High capillary pumping performance and heat transfer area capillary wicks can be obtained through micro/nano processing technology. This paper presents a comprehensive review on the types and applications of heat pipes and discusses the principles of enhancing heat transfer in heat pipes through micro/nano-structures. Furthermore, summarizes various fabrication methods for micro/nano-structured heat pipes, including chemical and oxidation treatment, laser processing, lithography technology and etching processes, electrical discharge machining, electrochemical deposition and so on. Finally, the characteristics of various fabrication methods together with the issues and challenges faced in the development of heat pipes are presented.