UV-LIGA与微细电火花加工组合制造微细电解阵列电极

采用UV-LIGA与微细电火花加工组合技术制造大长径比微细阵列电极.先通过UV-LI-GA技术制作微细群孔工具电极,然后通过电火花套料加工制作大长径比微细阵列电极.选取优化的工艺参数:前烘110℃保持12h;三步后烘50℃保持5min、70℃保持10min、90℃保持30min;采用谐振式电火花电源,电压200V、峰值电流1.5A、脉宽3.2μs、脉间6.4μs、放电间隙12μm等,制备了直径85μm、长1.5mm,长径比达17.65的微细阵列电极.最后用制作出的微细阵列电极作为工具电极进行微细电解加工实验,在120μm厚不锈钢板上电解加工出直径150μm、形状均匀的微细阵列群孔结构.实验证明:UV-LIGA与微细电加工组合制造技术是一种可行的制作高深宽比微结构的方法;利用微细阵列电极进行电解加工,能实现高效和高精度加工.     

双岛结构多晶硅压力传感器削角补偿技术的研究

详细讨论了双岛结构多晶硅压力传感器制作过程中的一种微机械加工技术,传感器采用的材料是双面抛学的（１００）晶面硅片,制作中还利用了半导体集成电路平面工艺。研制这种传感器遇到的主要问题是硅各向异性腐蚀的凸角削角问题,为削角补偿设计了两种特殊形状的掩膜结构,在实验中获得了满意的效果,并且制出了性能优良的双岛结构多晶硅压力传感器。     

Research on Nanofabrication Technology of Micro-/Nano-Stereo Rapid Prototyping of PCVD

At present, the most common micro/nano-scale fabri ca tion processes include the plane silicon process based on IC technology, stereo silicon process, LIGA, quasi-LIGA based on near ultra violet deep lithography, MEMS, energy beam etching and micro/nano-machining, etc. A common problem for t hese processes is the difficulty to fabricate arbitrary form for 3-dimensional micro/nano-parts, devices or mechanisms. To develop advanced MEMS manufacturin g technology, and to achieve fabrication of true 3-dimen...     

A New Process and Technology for Rapid Prototyping of A μ-Micro Motor

A new process and technology of rapid prototyping for a μ-micro motor is presented as a nontraditional machining and an advanced manufacturing technology (AMT) to be realized by using masks, including the operation principle of the motor, structure design, technique, driven circuit, and quality examination with Raman spectrum. The μ-micro motor is fabricated by the micro electro-mechanical systems (MEMS) process, the structure design must be considered to fabricate or assembly the parts during machining the motor in the meantime. The research proved that integration of IC (integrated circuit) process and MEMS using masks is effective in obtaining the rapid prototyping manufacturing of the μ-micro motor. With the mature technique to fabricate the motor, there are advantages to produce the motor in short time and with lower cost than before. The motor is a common power source of micro machines in military and civilian applications, for example, applied to micro robot, micro bio medicine, and micro machine. The size of the motor is 190 μm in maximum diameter by 125 μm in height that is bulk machined in array with the number of hundreds of micro motors on a substrate.     

一种微型直接甲醇燃料电池的制作与测试

微型直接甲醇燃料电池(micro direct methanol fuel cell,μ-DMFC)具有发电效率高、环境污染少、安全、携带方便等优点,在小型民用电源和单兵携带电源上具有广泛的应用.讨论了微型直接甲醇燃料电池(micro direct methanol fuel cell,μ-DMFC)的特点,研究了运用微机电系统(micro-electro-mechanical systems,MEMS)工艺,设计并且制作μ-DMFC的过程.主要是运用MEMS 工艺制作μ-DMFC的流场板;制备膜电极(membrane electrode assembly,MEA);通过改进μ-DMFC的封装结构,采用聚二甲基硅氧烷(polydimethylsiloxane,PDMS)和金属夹具对μ-DMFC进行封装,有效地避免甲醇的渗漏;并且通过测试μ-DMFC的I-V特性,比较了不同封装结构下,μ-DMFC的电性能.实验结果表明,封装结构改进后的μ-DMFC,最大电流密度为14.82 mA/cm2,最大输出功率为0.661 mW.     

高机械灵敏度悬空导电薄膜的制备方法研究

微机电系统中的悬空薄膜的制备技术是微结构制备的关键技术之一.研究了周边固支方形薄膜的机械灵敏度及通过浓硼扩散自停止腐蚀法制备高灵敏度悬空导电薄膜.实验结果表明,当扩散温度为1 175℃,扩散时间为3h,去除硼硅玻璃后四甲基氢氧化铵(TMAH)腐蚀液中腐蚀7.5h,可得到厚度为3μm,边长为5 mm,方块电阻为1.12 Ω/sq,致密均匀的悬空导电薄膜.给出了详细的制备工艺;针对扩散过程中出现的硼硅玻璃等问题,给出了切实可行的解决办法.     

Determination of Mechanical Properties of Micromembranes with Compressive Residual Stress

A novel model of a load-deflection method to determine the mechanical properties of micromembranes with compressive residual stress is described. Since thin film structures are frequently used in micro devices, characterisation of mechanical properties of thin films is desired by the design and fabrication of micromachines. In this paper, the mechanical properties of thin micromembranes under compressive stress are characterised, which are fabricated by bulk micromachining. The relation between the center deflection and the load pressure on a square membrane is deduced by modelling the membrane as an elastic plate having large deflection with clamped boundaries. According to the model, whether the membrane has initial deflection or not has no effect on the measurement result. The Young's modulus and residual stress are simultaneously determined. The mechanical properties of siliconoxide, silicon nitride membranes and composite membranes of polysilicon with silicon nitride are measured.     

脉冲加热下微尺度表面流动沸腾

利用微机电系统(MEMS)加工技术,在梯形微通道内集成特定形状(60 μm×100 μm)的Pt微加热器,通过改变脉冲加热电压及水的流速,采用高速摄像机观察并记录微加热器表面的流动沸腾现象,根据脉冲宽度2 ms下不同流速及热流时微加热器表面的核态沸腾及膜态沸腾现象得到了沸腾流型图.结果表明：在一定流速条件下,随着微加热器的热流增加,核态沸腾及膜态沸腾相继出现在微加热器表面,且核态沸腾开始向膜态沸腾转变;同时,增加水的流速,可使微加热器上发生核态沸腾及膜态沸腾所需的热流量增大.     

一种MEMS保险机构的工艺模拟和静态特性仿真分析

该文依据引信安全系统设计准则,设计了一种引信用MEMS保险机构。通过分析该机构的工作原理和作用过程可知,该机构可以满足引信依据双环境信息解除保险的安全性设计要求。采用仿真软件CoventorWare对该MEMS机构进行了工艺模拟和仿真,给出该MEMS保险机构的UV-LIGA加工工艺过程。UV-LIGA加工工艺中分别采用2次微电铸过程,得到固连在基板上的运动机构。最后借助ANSYS对该保险机构的力学性能进行了有限元分析,分析结果表明,该机构能够在应力允许范围达到运动位移要求。     

超微仿生扑翼飞行器压电双晶驱动器仿真与优化

为了设计高性能的超微仿生扑翼飞行器压电双晶驱动器,提出了结合正交试验与压电场、应力场等多物理场直接耦合有限元法,对微驱动器的结构、几何参数进行优化.根据正交试验表设计有限元仿真分析试验,对试验结果进行极差分析,得到各影响因素对驱动器弯曲角度指标影响的主次顺序,并获得了提高压电双晶片驱动器性能的最优化方案.仿真结果表明,多物理场优化方法大幅度提高了扑动角度,满足超微扑翼飞行器的设计要求.     

超声辅助微细电解制备微细圆柱体电极基础试验

分析了超声因素在微细电解制备微细圆柱体电极工艺中的作用机理,在自行研制的数字化微细电解加工系统上,以超声辅助微细电解的技术手段,利用初始直径400／μm的钨丝进行了微细圆柱体电极的制备试验．试验中重点分析了超声频率、加工电压、电极浸入深度等工艺因素对电极制备质量和制备效率的影响．试验结果表明,超声因素的介入可有效改善微细圆柱体电极制备的成型精度,且其制备效率可提高24．4％～41．2％．     

Surface Micromachining of Bulk Acoustic Wave Filters

The most common typical bulk acoustic wave (BAW) filters are fabricated using bulk micromachining technology, but they have several disadvantages. This paper describes a new structure for front end passband BAW filters manufactured using surface micromachining. Porous silicon is used as a thick sacrificial layer. The structure reduces the influence of the support film on the filter to improve the VLSI compatibility as well as the filter quality. The cross-talk between resonators with different frequencies can be dramatically reduced by using resonators with a self-supporting structure.     

耐高温压阻力敏硅芯片及静电键合工艺

采用微型机械电子系统(MEMS)技术制作出了平膜型硅隔离(SOI)耐高温压阻力敏硅芯片,采用静电键合工艺将该力敏硅芯片封装在硼硅玻璃环上,制作出倒杯式弹性敏感单元.分析了静电键合时力敏硅芯片与玻璃环的对准偏差对力敏硅芯片非线性的影响;实验验证了静电键合工艺对硅芯片温度性能的影响以及制作的耐高温压力传感器的性能.结果表明,对准偏差对硅芯片的非线性有较大影响;静电键合工艺对硅芯片的零位时漂和热零点漂移影响较小;制作的耐高温压力传感器具有优良的性能指标,能满足实际的工程应用需求.     

基于摄动法的微机械陀螺随机性能的统计分析

以一种通过体微机械加工技术制备的音叉振动式微机械陀螺为对象,基于随机摄动技术定量计算了微陀螺固有频率变异和检测输出电容变异的统计特征,以概率思想表达了微陀螺批量加工过程所带来的材料/尺寸随机误差对其性能的影响.通过所提出的影响因子这一概念反映了微陀螺参数变异对性能变异的敏感度.在详尽分析微陀螺众多参数影响因子的基础上获得了微陀螺最为关键的5个参数.这有限关键参数的获得,不仅为微陀螺的健壮性设计提供了方向,同时也为实际微陀螺的加工控制提供了量化的参考依据.     

以环形振荡器作为敏感单元的加速度传感器

为了解决传感器的数字化,提出了一种新的数字加速度传感器。它是由两个环形振荡器和一个混频器组成的频率输出型加速度传感器,其敏感元件是做在硅梁上的MOS环形振荡器。该传感器具有准数字输出、灵敏度高、温度系数低以及制作工艺简单等特点,其灵敏度可达到6.91kHz/g。分析了环形振荡器的频率特性,以及环形振荡器谐振频率和加速度的关系,设计并分析了加速度传感器的电路及物理结构,最后给出了试验结果。这种加速度传感器在军事和民用领域有广阔的应用前景。     

Advanced flow measurement and active flow control of aircraft with MEMS

Advanced flow measurement and active flow control need the development of new type devices and systems.Micro-electro-mechanical systems(MEMS) technologies become the important and feasible approach for micro transducers fabrication.This paper introduces research works of MEMS/NEMS Lab in flow measurement sensors and active flow control actuators.Micro sensors include the flexible thermal sensor array,capacitive shear stress sensor and high sensitivity pressure sensor.Micro actuators are the balloon actuator and synthetic jet actuator respectively.Through wind tunnel test,these micro transducers achieve the goals of shear stress and pressure distribution measurement,boundary layer separation control,lift enhancement,etc.And unmanned aerial vehicle(UAV) flight test verifies the ability of maneuver control of micro actuator.In the future work,micro sensor and actuator can be combined into a closed-loop control system to construct aerodynamic smart skin system for aircraft.     

Isolation of plasma from whole blood using a microfludic chip in a continuous cross-flow

A novel microfluidic chip is developed for crossflow filtration plasma from the whole blood which is carried out in a continuous manner. This microfluidic chip was made of a silicon substrate sealed with a compound cover. The silicon substrate fabricated by micro-electro-mechanical system (MEMS) technology consisted of microposts array, microchannels and reservoirs. Then the silicon substrate was characterized by Scaning Electron Microscopy (SEM). The performance of the microfluidic chip was valued by the experiments of plasma isolation. During more than one hour of continuous blood infusion through the chip, there were no problems of jamming or clogging, and the plasma selectivity of 97.78％ was achieved. Due to the chip’s simple structure and control mechanism with a continuous, real time operating manner, this microfluidic chip is easily expected to be integrated into micro total analytical system (μTAS) which will create a microanalysis system for point-of-care diagnostics.     

具有波纹形貌的聚苯胺微纳米管的制备及表征

以富勒烯C60微纳米纤维（fullerenemicro／nano fibers,FM／NFs）作为可容易移除模板,利用直接超声混合法,成功地制备了具有波纹形貌的聚苯胺微纳米管。光学显微镜观察表明,聚苯胺呈纤维状,其长度分布在2～5μm之间。扫描电镜和透射电镜观察结果表明,聚苯胺微纳米纤维形貌类似于波纹管,波纹周期约为100nm,外径在0．5～1μm之间,为空心管状结构。     

基于人工微台阶分选与捕获肿瘤细胞的微流控芯片

开发具有契合肿瘤细胞尺寸的微台阶结构的微流控芯片以将肿瘤细胞从正常人血细胞中分选并捕获出来．结合微加工技术,先后两次对同一块玻璃基底进行刻蚀,改变两次刻蚀的图样与时间最终与盖板间形成高度为10μm的微台阶结构,通过玻璃基底与有机高聚物PDMS（Polydimethylsiloxane）盖板的键合制作出微流控芯片．利用具有微台阶结构的芯片,悬浮于磷酸盐缓冲盐溶液中的肿瘤细胞（MCF-7）被全部捕获在微台阶结构内,尺寸小于台阶的正常人血细胞（红细胞）流过台阶未被捕获,实现了将肿瘤细胞从正常血细胞中分选并捕获．捕获在芯片中的肿瘤细胞都具有活性．芯片整体透明,肿瘤细胞捕获过程不需要进行化学修饰等预处理．     

单晶硅微尺度侧磨表面质量影响因素试验研究

为了获得具有较好表面质量的典型硬脆材料单晶硅微结构,采用微尺度磨削技术,利用直径为0.9 mm的微磨棒沿单晶硅(100)晶面进行磨削.首先通过三因素五水平的正交试验分析出影响单晶硅微尺度磨削表面粗糙度的主次因素;其次优化出获得较小表面粗糙度的单晶硅微尺度磨削工艺;最后通过单因素试验研究单晶硅微磨削表面粗糙度(Ra)随工艺参数的变化规律.结果表明:在沿单晶硅(100)晶面的微磨削过程(20 000 r/min≤v_s≤60 000 r/min,20μm/s≤v_w≤170μm/s和3μm≤a_p≤15μm)中,主轴转速对R_a影响最大;当主轴转速(v_s)为50 000 r/min、进给速度(v_w)为20μm/s、磨削深度(a_p)为3μm时,R_a最小;R_a随vs的增大基本呈减小趋势,但v_s过大时机床主轴出现振动,R_a出现增大趋势.R_a随v_w和a_p的增大而增大.