The exponential miniaturization of electronic chips over time, described by Moore’s law, has played a key role in our digital age. However, the operating power of small electronic devices is significantly limited by the lack of advanced cooling technologies available.
Aiming to tackle this problem, a study published in Cell Reports Physical Science, led by researchers from the Institute of Industrial Science, The University of Tokyo, describes a significant increase in performance for the cooling of electronic chips.
The most promising modern methods for chip cooling involve using microchannels embedded directly into the chip itself. These channels allow water to flow through, efficiently absorbing and transferring heat away from the source.
The efficiency of this technique is constrained, however, by the sensible heat of water. This quantity refers to the amount of heat needed to increase the temperature of a substance without inducing a phase change. The latent heat of phase change of water, which is the thermal energy absorbed during boiling or evaporation, is around 7 times larger than its sensible heat. “By exploiting the latent heat of water, two-phase cooling can be achieved, resulting in a significant efficiency enhancement in terms of heat dissipation,” explains Hongyuan Shi, lead author of the study.
Previous research has shown the potential of two-phase cooling, while also highlighting the complications of this technique, primarily due to difficulties in managing the flow of vapor bubbles after heating. Maximizing the efficiency of heat transfer depends on a variety of factors, including the geometry of the microchannels, the two-phase flow regulation, and the flow resistance.
This study describes a novel water-cooling system comprising three-dimensional microfluidic channel structures, utilizing a capillary structure and a manifold distribution layer. The researchers designed and fabricated various capillary geometries and studied their properties across a range of conditions.
It was found that both the geometry of the microchannel, through which the coolant flows, and the manifold channels, which control the distribution of coolant, influence the thermal and hydraulic performance of the system.
The measured ratio of useful cooling output to the required energy input, known as the coefficient of performance (COP), reached up to 10<sup>5</sup>, representing a notable advance over conventional cooling techniques.
“Thermal management of high-power electronic devices is crucial for the development of next-generation technology, and our design may open new avenues for achieving the cooling required”, says Masahiro Nomura, senior author.
High-performance electronics rely on advanced cooling technology, and this research could be key in maximizing the performance of future devices and achieving carbon neutrality.
