Investigation on an Ultrasonic Micro-knife Based on MEMS Technology

随着近20年来MEMS技术的快速发展，近来，如何将MEMS技术应用于医疗外科手术越来越受到研究人员的关注。本文研究了一种基于MEMS技术的超声微型手术刀，刀体集成有三轴应力传感器，并且设计了微制造工艺流程。论文的主要贡献与具体创新点主要如下： 1.比较了不同压电材料的优缺点，并确定了采用PZT-4作为微型手术刀的驱动器。微型手术刀基于半波长的变幅杆共振设计。在利用解析法和有限元法对单一指数形的变幅杆和圆锥形的变幅杆进行分析比较基础上，我们设计了刀体采用复合变幅杆结构，刀头带有齿状结构的超声微型手术刀，并首次提出了全偏心和半偏心两种结构。研究表明：采用对称结构的微型手术刀只沿着纵向做往复振动，...Recently there has been greatly interested in the use of MEMS for surgery due to the rapid development of MEMS technology during the past 20 years. In this thesis, we research on an ultrasonic micro-knife based on MEMS technology, and 3-axis stress sensors are integrated on it. The main contents of my works are summarized as follows: 1. Compared with the different piezoelectric materials, we use ...学位：工学硕士院系专业：物理与机电工程学院机电工程系_精密仪器及机械学号：1992007115119

Capacitive pressure sensor with circular island structure

改变传感器可动极板的结构是解决MEMS电容式压力传感器信号输出与压力输入呈非线性关系问题的方法之一。设计了一种新型结构电容式压力传感器,其可动极板是lPCVd氮化硅构成的一个方形薄膜,薄膜中心到边缘之间由PECVd氧化硅构筑一个环形岛棱,使可动极板在压力负载下的变形趋于平整,减小了边缘杂散电容带来的非线性,从而改善了该传感器的输出特性。利用有限元方法分析了不同尺寸的动极板在不同外加压力作用下压力与形变的关系,以及相应的应力分布情况,并采用最小二乘拟合直线法计算了压力传感器的线性度。分析结果表明,与常规的双极板微型电容式压力传感器相比,新型结构压力传感器的线性度改善了48 .38 %,达到了1 .6 %。A capacitive pressure sensor with a new movable electric plate structure is presented to improve the output nonlinearity of a MEMS-based capacitive pressure sensor.The movable plate of the sensor is a rectangular memrance made of LPCVD silicon nitride film,and a circular island is added from the center to the edge of the membrane by depositing and patterning a layer of PECVD silicon dioxide.With this structure,the deformation of the movable plate of the capacitive pressure sensor will tend to flat when applying a load of pressure,so that the nonlinearity of stray capacitance near the edge of the entire structure is decreased and the output properties of the sensor is improved.Moreover,the Finite Element Model( FEM) in ANSYS is used to analyze the new structure of the movable electrical plate with different dimensions to obtain the relationship between deflection and pressure and the corresponding stress distribution and a curve fitting based on the least-square method is applied to calculate the output linearity of the sensor.Comparison of the MEMS-based capacitive pressure sensor with a general structure sensor,the output linearity of the proposed sensor has been improved by 48.38%,reaching 1.6%.SupportedbytheNationalPlanforUndergraduateExperimentalCreativeInvestigation(GrantNo.2008102218712

中国科学院科学数据网格建设的进展

中国科学院科学数据网格是在中国科学院科学数据库的基础上构建的数据网格群,其目的是整合物理上分布的科学数据资源,形成逻辑统一的数据资源视图,提供透明的数据访问,并基于这些科学数据和网格上的先进的计算与存储设施,提供科学数据分析、处理和可视化,实现便捷的科学数据应用服务,形成中国科学院科学数据应用环境的发展构架。作为中国科学院科学数据网格建设的第一阶段,首先进行了网格总中心和四个学科领域的科学数据网格试点:化学数据网格、空间科学数据网格、微生物与病毒学数据网格和人地系统科学数据网格的建设。本文介绍了本阶段建设的主要进展与成果,并对未来工作进行了展望