Direct measurements of thermal transport in glass and ceramic microspheres embedded in an epoxy matrix
Direct measurements of thermal transport in glass and ceramic microspheres embedded in an epoxy matrix
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DOI：
10.1063/5.0055038
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发表时间：
2021-07
影响因子：
4
通讯作者：
Matthew F. Thompson;Xuewang Wu;Dingbin Huang;Yingying Zhang;N. Seaton;Chi Zhang;Matthew T. Johnson;J. Podkaminer;Victor Ho;Xiaojia Wang
中科院分区：
文献类型：
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作者：
Matthew F. Thompson;Xuewang Wu;Dingbin Huang;Yingying Zhang;N. Seaton;Chi Zhang;Matthew T. Johnson;J. Podkaminer;Victor Ho;Xiaojia Wang
采用时域热反射计量法对复合材料中填充颗粒的导热系数进行了测量。具体地说，将直径为100~150μm的玻璃和陶瓷微球嵌入到环氧树脂基质中作为典型的复合热界面材料(TIM)的代表，该材料适用于微电子应用。这些测量提供了对填充材料热性能的直接表征。测得的硼硅酸盐玻璃微球和氧化钇稳定氧化锆微球的热导率与体相材料的文献值吻合较好，而氧化铝微球的热导率比大块晶体的热导率低近50%。氧化铝微球热导率的降低突显了这一水平的理解对TIM发展的重要性，并归因于结构不均匀导致的声子散射增强，例如相混合和微孔导致的缺陷。结合样品制备、结构表征和直接热测试，我们的研究揭示了单个微球的结构与热性能之间的关系。这项工作的结果可以为热管理应用的复合材料基导热材料的设计和工程提供便利。
The time-domain thermoreflectance metrology is applied to evaluate the thermal conductivities of filler particles embedded in a composite matrix. Specifically, a system of glass and ceramic microspheres with a diameter of 100 to 150 μm embedded in an epoxy matrix was used as a representation of a typical composite thermal interface material (TIM) suitable for microelectronics applications. These measurements provide a direct characterization of the thermal properties of filler materials. The measured thermal conductivities of both borosilicate glass and yttria stabilized zirconia microspheres agree well with literature values for bulk materials, whereas the thermal conductivity of the alumina microspheres is nearly 50% lower than that of bulk crystals. The reduction in thermal conductivity of the alumina microspheres highlights how important this level of understanding is for TIM development and is attributed to enhanced phonon scattering due to structural heterogeneity, such as defects induced by phase mixing and microvoids. Combining sample preparation, structural characterization, and direct thermal measurements, our study reveals the structure–thermal property relationship for individual microspheres. The results of this work can facilitate the design and engineering of composite-based thermally conductive materials for thermal management applications.