Thin Film Materials and the Minimum Thermal Conductivity

摘要提案编号：CTS 9978822主要研究者：D.卡希尔这个奖项是为了支持在薄膜热传导晶格振动的基础科学问题的研究。薄膜和纳米级的高度无序的材料的多层膜将通过磁控溅射和卢瑟福背散射光谱，扫描电子显微镜和X射线反射率的特点。 这些材料中的热传输将使用3 Ω方法在35-500 K的温度范围内进行量化，并且将使用皮秒超声波测量声音的纵向速度。 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。 其目的是建立一个更好的理解机制，创造高和低的热导率的薄膜材料与大的障碍。这一新的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.