微机械圆盘谐振器的仿真分析及等效电路

通过对径向振动圆盘的机械振动方程进行分析,将机械振动的分散参数集总化,提取出机械集总参量并通过机电类比的方法将集总化的机械参量类比成电参量,建立起径向振动微机械谐振器的电参数模型。利用ANSYS软件对径向振动盘式微机械谐振器进行模拟,提取出谐振频率和振动位移,并以此为基础计算出等效质量及阻尼和刚度的数值,进而通过机电耦合系数求出电参数值。以所提取的电参数为依据,分析了谐振器的结构对谐振器的等效阻抗的影响。谐振器的等效电路及分析结果将成为后续结构和驱动电路设计的出发点。     

MEMS微针的最新研究进展

介绍了MEMS微针技术在微针制备工艺、力学和流体性能模拟以及透皮给药方面研究的近况。描述了硅、金属和聚合物材料的微针制备工艺,分析了这些材料在MEMS微针应用上的优缺点。比如硅微针制备工艺成熟但是硅的质地太脆;金属微针机械强度高却不易载药;聚合物微针易于批量化复制但是机械强度差。进一步阐述了微针研究取得的进展,总结了微针技术发展需要解决的关键问题。微针制备工艺已经日趋成熟,微针将朝着可复制化、批量化方向发展,微针经皮给药将逐渐从动物实验转移到人体实验,以实现微针研究的最终目的——临床给药。     

Sensitivity of MEMS microwave power sensor with the length of thermopile based on Fourier equivalent model

A Fourier equivalent model is introduced to research the thermal transfer behavior of a terminating-type MEMS microwave power sensor.The fabrication of this MEMS microwave power sensor is compatible with the GaAs MMIC process.Based on the Fourier equivalent model,the relationship between the sensitivity of a MEMS microwave power sensor and the length of thermopile is studied in particular.The power sensor is measured with an input power from 1 to 100 mW at 10 GHz,and the measurement results show that the power sensor has good input match characteristics and high linearity.The sensitivity calculated from a Fourier equivalent model is about 0.12,0.20 and 0.29 mV/mW with the length at 40,70 and 100μm,respectively,while the sensitivity of the measurement results is about 0.10,0.22 and 0.30 mV/mW,respectively,and the differences are below 0.02 mV/mW. The sensitivity expression based on the Fourier equivalent model is verified by the measurement results.     

Study of hybrid orientation structure wafer

Two types of 5μm thick hybrid orientation structure wafers,which were integrated by（110）or（100） orientation silicon wafers as the substrate,have been investigated for 15-40 V voltage ICs and MEMS sensor applications.They have been obtained mainly by SOI wafer bonding and a non-selective epitaxy technique,and have been presented in China for the first time.The thickness of BOX SiO₂ buried in wafer is 220 nm.It has been found that the quality of hybrid orientation structure with（100）wafer substrate is better than that with（110）wafer substrate by"Sirtl defect etching of HOSW".     

微纳米分子系统研究领域的最新进展——IEEE NEMS 2011国际会议综述

2011年2月20日至23日,第6届IEEE国际纳米/微米工程及分子系统大会（IEEE-NEMS 2011）在台湾高雄市召开,来自世界各地的300多位专家、学者齐聚一堂,分享其在微纳米科技领域的最新研究成果。本文选取微流体技术与芯片实验室、生物医学MEMS器件、纳米新材料奇妙特性及其应用、新型传感器执行器及其系统等4个角度,详细介绍了微纳米科技领域的研究现状,并对其发展趋势进行了分析。     

EMC材料特性对MEMS加速度计封装可靠性的影响

采用有限元法分析了EMC(环氧模塑封材料)材料特性对MEMS(微电子机械系统)加速度计封装可靠性的影响.使用有限元软件ANSYS分别模拟了加速度计的输出电压、悬臂梁的挠度以及加速度计芯片的等效应力在温度循环载荷下的变化情况.结果发现,EMC的材料模式不同,MEMS加速度计的性能有明显差异.在使用EMC温度相关弹性模式和...     

Size effect on the static behavior of electrostatically actuated microbeams

We present a new analytical model for electrostatically actuated microbeams to explore the size effect by using the modified couple stress theory and the minimum total potential energy principle. A material length scale parameter is introduced to represent the size-dependent characteristics of microbeams. This model also accounts for the nonlinearities associated with the mid-plane stretching force and the electrostatical force. Numerical analysis for microbeams with clamped-clamped and cantilevered conditions has been performed. It is found that the intensity of size effect is closely associated with the thickness of the microbeam,and smaller beam thickness displays stronger size effect and hence yields smaller deffection and larger pull-in voltage. When the beam thickness is comparable to the material length scale parameter,the size effect is significant and the present theoretical model including the material length scale parameter is adequate for predicting the static behavior of microbeam-based MEMS.     

基于MEMS惯性技术的鞋式个人导航系统

研究了低精度鞋式个人惯性导航系统的导航修正算法.该系统由低精度MEMS惯性IMU单元组成,固联在步行者的鞋上.导航算法在传统捷联惯性导航算法基础上,引入了零速修正技术,根据人行走时脚部运动的加速度统计特性,设计了一种比力模值+滑动方差检测算法,用以检测行走过程中的静止时间段.然后通过设计的改良卡尔曼滤波器在静止时间段内滤波估计导航姿态、速度和位置的计算误差,通过反馈校正可以提高原系统的导航精度.最后通过两组MEMS实物实验验证了导航修正算法的有效性和可行性,并指出了进一步的研究方向.     

微小型航姿测量系统及其数据融合方法

以小型无人机航姿测量系统的微小型化为背景,利用MEMS惯性测量元件研制了一种低成本微型航姿测量系统.针对MEMS器件用于载体航姿测量时精度低、易发散的问题,提出一种计算量小、实时性强的加速度信息、磁场强度信息、陀螺信息的融合方法.采用卡尔曼滤波器对系统的俯仰角、滚转角和航向角的误差进行最优估计;设计数据融合的判别准则,并根据判据的判断结果调整卡尔曼滤波器中的量测信息,使系统可用于小型无人机的定高自主飞行.实验结果表明,系统输出航姿的更新频率可达100Hz,航姿测量误差小于0.6°,航姿标准差小于0.09°;将其应用于某小型固定翼飞行器的飞行控制系统中进行自主飞行实验,完成了预定的飞行任务.     

桥梁索力测量无线组网系统

设计实现了一种基于Zig Bee无线组网的桥梁索力测量系统。该系统采用TI公司的CC2530芯片组建无线数据传输网络,采用MEMS传感器对桥梁多个拉索进行布点,用STM32芯片组成控制处理模块,实现一次性同步得到桥梁多拉索的索力数据,解决了桥梁监测数据采集麻烦问题。该系统具有节点功耗小、传输距离远、组网容易、成本低、网络容量大等优势,现场应用实验效果较好。