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arXiv · 2201.00516

Deep-potential enabled multiscale simulation of gallium nitride devices on boron arsenide cooling substrates

Abstract

High-efficient heat dissipation plays critical role for high-power-density electronics. Experimental synthesis of ultrahigh thermal conductivity boron arsenide (BAs, 1300 W m-1K-1) cooling substrates into the wide-bandgap semiconductor of gallium nitride (GaN) devices has been realized. However, the lack of systematic analysis on the heat transfer across the BAs-GaN interface hampers the practical applications. In this study, by constructing the accurate and high-efficient machine learning interatomic potentials, we performed multiscale simulations of the BAs-GaN heterostructures. Ultrahigh interfacial thermal conductance (ITC) of 265 MW m-2K-1 is achieved, which lies in the well-matched lattice vibrations of BAs and GaN. Moreover, the competition between grain size and boundary resistance was revealed with size increasing from 1 nm to 100 μm. Such deep-potential equipped multiscale simulations not only promote the practical applications of BAs cooling substrates in electronics, but also offer new approach for designing advanced thermal management systems.

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Jing Wu, E Zhou, An Huang, Hongbin Zhang, Ming Hu, Guangzhao Qin. 2024-01-24. Deep-potential enabled multiscale simulation of gallium nitride devices on boron arsenide cooling substrates. https://arxiv.org/abs/2201.00516

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