Thermal conductivity and its anisotropy research of germanium thin film
Thermal conductivity and its anisotropy research of germanium thin film
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DOI：
10.1007/s00231-010-0731-2
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发表时间：
2011-04
影响因子：
2.2
通讯作者：
Z. H. Wang;M. Ni
中科院分区：
文献类型：
--
作者：
Z. H. Wang;M. Ni
锗是半导体和微电子工业中的重要元素。在同一温度下，它的热导率在锗晶体中是一个恒定的各向同性参数，在薄膜中很难测量。本文采用非平衡分子动力学模拟方法和Stillinger-Weber势模型，研究了Ge薄膜的法向和切向导热系数。Ge薄膜的法向和切向导热系数存在明显的各向异性和尺寸效应。在理论分析中，用玻耳兹曼输运理论分析了锗薄膜中的声子输运。理论结果进一步证实了薄膜热导率的各向异性和尺寸效应，表明薄膜中的声子平均自由程和优势边界声子散射显著减小。
Germanium is an important element in semiconductor and microelectronics industries. Its thermal conductivity is an invariable and isotropic parameter in germanium crystal in the same temperature and its thermal conductivity is difficult to be measured in thin film. In the present paper, using the non-equilibrium molecular dynamics simulation method and Stillinger–Weber potential model, the normal and tangential thermal conductivity of germanium thin film are studied. There are remarkable anisotropy and size effect of thermal conductivity in normal and tangential direction of germanium thin film. In the theoretical analysis, Boltzmann transport theory is used to analyze the phonon transport in germanium thin film. Theoretical results further demonstrate the anisotropy and size effect of thermal conductivity in thin film, which indicate the significant decrease of phonon mean free path and predominant boundary phonon scattering in germanium thin film.