微机械多层短接式蓝牙天线

集成电路与微机械天线对于基底介质的要求不同,前者需要高介电常数的介质,而后者所需介质的介电常数则较低,要将两者集成到一起存在一定困难.为了满足蓝牙通信器件的需要,以便将微带天线与电路集成在一起,设计了背腔-短接式微带贴片天线,并采用微机械加工工艺制作了样品,其10dB带宽达到了10%以上,辐射效率为67%,长度仅为1/6波长,基本达到了蓝牙通信器件的要求.     

Design of a Microfluidic System to Investigate the Mechanical Properties of Layer‐by‐Layer Fabricated Capsules

A microfluidic system was designed, fabricated and implemented to study the behavior of polyelectrolyte capsules flowing in microscale channels. The device contains microchannels that lead into constrictions intended to capture polyelectrolyte microcapsules which were fabricated with the well‐known layer‐by‐layer (LbL) assembly technique. The behavior of hollow capsules at the constrictions was visualized and the properties of the capsules were investigated before and after introduction into the device.

Time series of video frames showing capsules being compressed into a constriction.     

基于光致抗蚀干膜的掩膜制备及其应用研究

在传统工艺流程中,必须先将干膜贴于工件表面,然后进行光刻,但干膜不可重复使用。现提出一种新型干膜光刻工艺流程,在干膜贴于工件表面之前,先对干膜单独进行光刻试验研究。基于该新型工艺流程,研究了杜邦干膜GPM220的曝光及显影特性。经过对曝光量（曝光时间）及显影时间的参数优化,最终在干膜上获得了平均直径为99.7μm的通孔阵列,并将其作为掩膜应用于微细电解加工,通过选择合理的加工参数,在工件表面获得了平均直径为125μm、平均深度为10μm的微坑阵列。电解实验后的干膜易与工件分离,可实现重复使用,提高了干膜的利用率。     

微间隙击穿性能的研究

本文对微米量级微间隙的电击穿性能进行了研究,在制作出微间隙试样的基础上,改变微间隙所处环境气氛以及间隙距离,测试了不同条件下的击穿电压V相对于气体压强P的关系曲线,系统研究了N_2、O_2、Ar、He、Ne等环境气氛以及间隙距离对微间隙击穿性能的影响,对微间隙的静电击穿机制也进行了一些有益的探讨。     

微型压阻式压力传感器的研制

用微机械加工技术开发出一种微型方杯压阻式压力传感器。文中介绍了微型压力传感器的设计思想和研制工艺中的关键技术，并给出了该传感器的参数。测试结果表明该传感器的主要性能已达到国内先进水平。     

An analytical model of the effect of particle size distribution on the surface profile evolution in abrasive jet micromachining

An analytical model to estimate the spatial distribution of erosive efficacy across the mask opening in the abrasive jet micromachining (AJM) of substrates is presented. A closed form analytical expression is derived which allows the erosive efficacy in the vicinity of the mask edge to be estimated as a function of the measured abrasive particle size distribution and the width of the mask opening. This analytical expression was used in a previously developed analytical surface evolution model to predict the time dependent eroding surface profiles of micro-holes and micro-channels of various sizes in glass and polymethylmethacrylate (PMMA), using aluminum oxide abrasive powders of different sizes. Use of the measured powder size distributions in the analytical models resulted in excellent agreement between the measured and model predicted channel profiles. The results of the study demonstrate that the particle size distribution and mask opening width can greatly affect the shape and depth of micro-channel profiles. A major improvement over previously developed models is ease-of-application since the erosive efficacy is given by an analytical expression rather than by the use of a computer simulation or a semi-empirical approach.     

MEMS技术的发展与应用

主要介绍了MEMS技术的背景、分类、应用、发展趋势。     

Noncrystalline micromachining of amorphous alloys using femtosecond laser pulses

Femtosecond laser micromachining of a Zr-based amorphous alloy in air, including measuring the ablation threshold, micro-drilling and trenching, was investigated. The threshold of ablating this amorphous alloy was determined by experiment. Laser-induced ablation and associated damage were examined by means of optical microscope, scanning electron microscopy, transmission electron microscopy and electron diffraction diagram. The results show that conventional processing method induced defects in the vicinity of machined area, such as crystallization, molten trace and spatter, were absent in femtosecond laser ablation area with selected parameters. This indicates that femtosecond laser ablation is a promising method for micromachining amorphous alloys without crystallization.     

Porous Silicon Micromachining to Position Optical Fibres in Silicon Integrated Optical Circuits

Low-loss optical fibre connections require deep grooves etched in silicon substrate for accurate fibre positioning. As shown in this paper these grooves can be obtained by using localised formation of porous silicon on patterned substrates. Cr-Au masking layer with a duration in HF solution longer than 30 min is used to fabricate grooves with a depth higher than 75 m. N⁺-type silicon provides grooves with a pseudo-V shape which is compatible with accurate fibre alignment. By using this technology, arrays of optical fibres are positioned with an accuracy higher than 1 m.     

3D light scanning macrography

The technique of 3D light scanning macrography permits the non-invasive surface scanning of small specimens at magnifications up to 200×. Obviating both the problem of limited depth of field inherent to conventional close-up macrophotography and the metallic coating required by scanning electron microscopy, 3D light scanning macrography provides three-dimensional digital images of intact specimens without the loss of colour, texture and transparency information. This newly developed technique offers a versatile, portable and cost-efficient method for the non-invasive digital and photographic documentation of small objects. Computer controlled device operation and digital image acquisition facilitate fast and accurate quantitative morphometric investigations, and the technique offers a broad field of research and educational applications in biological, medical and materials sciences.