Department of Civil and Environmental Engineering, Rice University , Houston, Texas 77005, United States.
Department of Materials Science and NanoEngineering, Rice University , Houston, Texas 77005, United States.
ACS Appl Mater Interfaces. 2017 Jan 11;9(1):989-998. doi: 10.1021/acsami.6b09482. Epub 2016 Dec 1.
Improving heat transfer in hybrid nano/microelectronic systems is a challenge, mainly due to the high thermal boundary resistance (TBR) across the interface. Herein, we focus on gallium nitride (GaN)/diamond interface-as a model system with various high power, high temperature, and optoelectronic applications-and perform extensive reverse nonequilibrium molecular dynamics simulations, decoding the interplay between the pillar length, size, shape, hierarchy, density, arrangement, system size, and the interfacial heat transfer mechanisms to substantially reduce TBR in GaN-on-diamond devices. We found that changing the conventional planar interface to nanoengineered, interlaced architecture with optimal geometry results in >80% reduction in TBR. Moreover, introduction of conformal graphene buffer layer further reduces the TBR by ∼33%. Our findings demonstrate that the enhanced generation of intermediate frequency phonons activates the dominant group velocities, resulting in reduced TBR. This work has important implications on experimental studies, opening up a new space for engineering hybrid nano/microelectronics.
改善混合纳米/微电子系统中的热传递是一项挑战，主要是因为界面处的高热阻（TBR）。在此，我们专注于氮化镓（GaN）/金刚石界面-作为具有各种高功率、高温和光电应用的模型系统-并进行广泛的反向非平衡分子动力学模拟，解析柱长、尺寸、形状、层次结构、密度、排列、系统尺寸以及界面热传递机制之间的相互作用，以大幅降低 GaN 上金刚石器件中的 TBR。我们发现，将传统的平面界面改为具有最佳几何形状的纳米工程交错结构，可将 TBR 降低 80%以上。此外，引入保形石墨烯缓冲层可将 TBR 进一步降低约 33%。我们的研究结果表明，中间频率声子的增强产生激活了主导群速度，从而降低了 TBR。这项工作对实验研究具有重要意义，为混合纳米/微电子工程开辟了新的空间。
