Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA.
Nanoscale. 2017 Dec 21;10(1):167-173. doi: 10.1039/c7nr07058f.
The rapid development of high power density devices requires more efficient heat dissipation. Recently, two-dimensional layered materials have attracted significant interest due to their superior thermal conductivity, ease of production and chemical stability. Among them, hexagonal boron nitride (h-BN) is electrically insulating, making it a promising thermal management material for next-generation electronics. In this work, we demonstrated that an h-BN thin film composed of layer-by-layer laminated h-BN nanosheets can effectively enhance the lateral heat dissipation on the substrate. We found that by using the BN-coated glass instead of bare glass as the substrate, the highest operating temperature of a reduced graphene oxide (RGO) based device could increase from 700 °C to 1000 °C, and at the same input power, the operating temperature of the RGO device is effectively decreased. The remarkable performance improvement using the BN coating originates from its anisotropic thermal conductivity: a high in-plane thermal conductivity of 14 W m K for spreading and a low cross-plane thermal conductivity of 0.4 W m K to avoid a hot spot right underneath the device. Our results provide an effective approach to improve the heat dissipation in integrated circuits and high power devices.
高功率密度器件的快速发展需要更高效的散热。最近，二维层状材料因其优异的导热性、易于制备和化学稳定性而引起了极大的关注。其中，六方氮化硼（h-BN）是电绝缘的，因此有望成为下一代电子设备的热管理材料。在这项工作中，我们证明了由层层叠叠的 h-BN 纳米片组成的 h-BN 薄膜可以有效地增强衬底上的横向散热。我们发现，通过使用 BN 涂层玻璃代替裸玻璃作为衬底，基于还原氧化石墨烯（RGO）的器件的最高工作温度可以从 700°C 提高到 1000°C，并且在相同的输入功率下，RGO 器件的工作温度可以有效地降低。使用 BN 涂层实现的显著性能提升源于其各向异性的热导率：扩散时的高面内热导率为 14 W m K，而低的横向热导率为 0.4 W m K，可以避免器件下方出现热点。我们的结果为改善集成电路和高功率器件的散热提供了一种有效方法。
