Thin Film Materials and the Minimum Thermal Conductivity

摘要提案号：CTS 9978822首席研究员：D. cahill该奖项旨在支持基于晶格振动的薄膜热传导基础科学问题的研究。采用磁控溅射法制备高度无序材料的薄膜和纳米级多层材料，并用卢瑟福后向散射光谱、扫描电镜和x射线反射率对其进行表征。这些材料的热传输将在35-500 K温度范围内使用3-omega方法进行量化，并且将使用皮秒超声波测量纵向声速。这种测量组合将有助于详细比较热导率数据和最小热导率模型。目的是建立一个更深入的了解机制，创造高和低的热传导率在薄膜材料与大无序。这一新知识也有望扩大可用于应用的薄膜热性能的范围。

ABSTRACTProposal Number: CTS 9978822Principal Investigator: D. CahillThis award is to support studies of the fundamental scientific issues in heat conduction in thin films by lattice vibrations. Thin films and nanometer-scale multilayers of highly disordered materials will be prepared by magnetron sputtering and characterized by Rutherford backscattering spectroscopy, scanning electron microscopy and x-ray reflectivity. Heat transport in these materials will be quantified using the 3-omega method in the temperature range 35-500 K, and longitudinal speeds of sound will be measured using picosecond ultrasonics. This combination of measurements will facilitate a detailed comparison between the thermal conductivity data and the minimum thermal conductivity model. The objective is to establish a greater understanding of the mechanisms that create high and low thermal conductivities in thin film materials with large disorder. This new knowledge is also expected to expand the range of thin film thermal properties that are available for applications.