摘要
微电子机械系统 (MEMS)是结合微电子技术和微机械加工技术制造而成的微型机电一体化系统。MEMS中薄膜材料的厚度可达到微米、亚微米直至纳米量级。由于微尺度效应 ,薄膜材料的导热规律及其各种热物性参数 (如比热、热导率、热扩散率等 )与常规材料显著不同。设计MEMS时必须充分考虑微尺度效应 ,并使用合理的热物性参数值 ,才能保证微电子机械系统的热稳定性。本文从理论建模、实验测试和计算机模拟三个方面总结了近年来微尺度薄膜热物性的研究进展。
Micro-electro-mechanical systems (MEMS) are the micro-mechatronics fabricated by microelectronic technology and micromachining. The thickness of thin films in MEMS can meet micrometers, submicrometers, and even nanometers. Because of microscale effect, thermophysical properties (such as specific heat, thermal conductivity and thermal diffusivity) and heat transfer rule of thin-film materials are remarkably different from that of bulk materials. Microscale effect must be carefully concerned and reasonable thermophysical properties value must be used in the design of MEMS to ensure thermal stability of MEMS and micro devises. This paper summarizes the progress of study on thermal properties of microscale thin-films in three sides of theoretical modeling, experimental testing and computer simulation, respectively. For the theoretical modeling, this paper reviews the history form Fourier analysis to non-Fourier analysis, then to the Casimir model, and lastly, to the general Fourier law that includes time relaxations for both of temperature and heat flux. On the other hand, form statistics point of view, the role of Boltzmann equation (BTE) is emphasized to the study of heat transfer in microscale. Based BTE, some hypothesizes such as phonon-electron interaction model, phonon scattering model, thermal wave model, and so on are introduced. The transport regimes for three common energy carders, electron, photon, and phonon, are also shown in this paper. For the experimental measurement of thermal properties of thin-films, short laser pulse, 3ω, microcalorimeter, and some other methods are illustrated. For computer simulations, molecular dynamics and Monte Carlo analysis are simply presented.
出处
《机械强度》
EI
CAS
CSCD
北大核心
2001年第4期465-470,共6页
Journal of Mechanical Strength
基金
国家自然科学基金重大项目 (59995550 5)
教育部骨干师资计划 (2 0 0 0 65)的资助
关键词
微尺度
薄膜
热物性参数
微电子机械系统
Microscale
Thin films
Thermal properties
Micro electro mechanical system
