Peking University Researchers Develop High-Efficiency Dielectric Cooling System for Microchips

Engineers at Peking University have introduced a new thermal management design that allows high-performance microchips to run cooler without the short-circuit hazards associated with water cooling. The methodology uses an embedded microfluidic channel system carved directly into the semiconductor substrate, utilizing a non-conductive dielectric fluid to carry heat away through vaporization.

As modern integrated circuits pack greater processing density into smaller footprints, managing thermal output has become one of the primary constraints in hardware engineering. Traditional embedded cooling strategies carve micro-channels directly into a chip's supporting substrate to circulate liquid coolant near high-temperature operational areas. While water-based cooling loops can achieve heat flux dissipation levels of up to 3,000 watts per square centimeter, water carries electrical conductivity risks if impurities dissolve into the stream, creating the danger of short circuits that can destroy electronic components, according to coverage by TechXplore (https://techxplore.com/news/2026-10-vapor-channels-powerful-chips-cool.html).

To eliminate electrical conductivity risks, hardware developers have turned to dielectric fluids, which act as electrical insulators. However, liquid dielectric coolants historically provided significantly lower thermal transfer capabilities than water. In a research paper published in Nature Electronics, Peking University researchers Wei Xiao, Zhihu Wu, and their co-authors presented a method that boosts the heat extraction efficiency of non-conductive liquids using a two-phase architecture.

The research team's setup relies on a dielectric fluid designated as HFE-7100, which absorbs heat by transitioning from liquid to vapor directly inside the microfluidic channel networks. Central to the design is a specialized structural arrangement known as a horizontal-up manifold. This assembly incorporates horizontal entry points to supply liquid coolant alongside vertical evacuation pathways designed to rapidly discharge rising vapor.

In initial laboratory trials, the cooling framework achieved a critical heat flux of 1,570 watts per square centimeter. This metric measures the rate of heat transfer per unit of surface area before liquid boiling degrades cooling effectiveness. Previously, embedded cooling techniques utilizing dielectric fluids were limited to thermal flux thresholds below 1,000 watts per square centimeter, even when combined with pre-pressurization or pre-cooling mechanisms.

A key feature of the team's cooling framework is its alignment with commercial semiconductor production processes. The researchers fabricated the micro-channels and manifold structures using standard microelectromechanical systems (MEMS) fabrication techniques. This compatibility allows the thermal management architecture to integrate with standard semiconductor processes and scale for future electronics without requiring radical retooling of fabrication lines.

The authors noted that further validation will require testing the cooling architecture on commercially available electronic devices and over longer operational periods to establish the system's long-term performance and reliability.