空气阻尼和残余应力对平面悬空薄膜振动特性的影响研究

项目名称： 空气阻尼和残余应力对平面悬空薄膜振动特性的影响研究

项目编号： No.51505076

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 马树军

作者单位： 东北大学

项目金额： 20万元

中文摘要： 平面悬空薄膜在微/纳机电系统中具有极其重要的应用价值，广泛用于通讯、国防、机械、生物医学等众多领域。空气阻尼和残余应力会直接影响到悬空薄膜振动特性和品质因子，进而影响器件的功能性与可靠性。为此，本项目拟利用薄膜沉积、光刻掩膜、硅刻蚀等微加工技术制备硅基悬空SiC和SiN 自由薄膜器件，研制精确可控与可测量的真空测试装置，利用纳米压痕仪、显微式激光多普勒测振仪等多种先进实验测试仪器和Rayleigh-Ritz能量法、有限元分析等理论与数值方法，对具有不同残余应力的SiC和SiN悬空薄膜在不同真空度下的振动特性与品质因子进行系统研究；探究空气阻尼和残余应力对悬空薄膜共振频率和品质因子的影响。研究结果可准确获取空气阻尼和残余应力对悬空薄膜结构振动的影响关系，可进一步优化纳米薄膜器件的设计和性能。

中文关键词： 动态特性；空气阻尼；残余应力；悬空薄膜；品质因子

英文摘要： Planar, suspended films play an significantly important role in the applications of MEMS/NEMS, which are widely used in the fields of telecommunication, defense, mechanical engineering, biomedical engineering and so on. Air damping and residual stress can directly affect the vibrations and quality factors of suspended films, which will further have effect on the functionality and reliability of the device. Therefore, this project will apply microfabrication technologies, including thin film deposition, photolithography to fabricate suspedned SiC and SiN membranes on Si substrates. Also an accurately controllable and measurable vacuum system will be designed. The dynamic characterisitics and quality factors of SiC and SiN membranes with a large range of residual stress will thus be systemically investigated in different vacuums by using experimental methods of nanoindentation and microscopic laser Doppler vibrometer, numerical method of finite element analysis and theoretical method of Rayleigh-Ritz energy method. Thus, the influence of air damping and residual stress on resonant frequencies and quality factors of suspended films will be studies as well. The research results will obtain the accurate effects of air damping and residual stress on vibrations of suspened thin film structures, which will further optimize the design and performance of nano thin-film devices.

英文关键词： dynamic characteristics;air damping;residual stress ;suspended thin films;quality factor