中国微米纳米-微纳结构对电容式柔性压力传感器性能影响的研究

设计制备出三明治结构的电容式柔性压力传感器,并对其性能进行研究.该传感器以银纳米线为电极材料,聚二甲基硅氧烷(PDMS)为柔性衬底,同时采用毛面玻璃和光面玻璃分别作为柔性衬底的制备模板,制备出微纳结构和平面结构的PDMS薄膜.然后采用喷涂法制备AgNWs/PDMS复合电极,以另外一层PDMS为介电层,将两电极面对面封装,得到电容式柔性压力传感器,最后系统研究了传感器的电极微纳结构对器件性能的影响.本文研究表明,具有微纳结构的AgNWs/PDMS复合薄膜传感器的灵敏度为1.0 kPa-1,而平面结构的AgNWs/PDMS复合薄膜传感器的灵敏度为0.6 kPa-1,由此可知具有微纳结构的柔性衬底能够显著提高器件的灵敏度.     

具有3D微纳结构PDMS阵列免疫传感芯片研制

介绍了一种简便快速加工微阵列免疫传感芯片的新方法。采用化学刻蚀技术加工具有μm级山脉状起伏和nm级表面粗糙度结构(简称为3D微纳表面)的玻璃阳模,以该阳模为模板浇注法制得表面具有3D微纳表面结构的PDMS基片,再借助于物理吸附,将抗体直接固定于该PDMS表面,形成具有3D微纳结构的PDMS微阵列免疫传感器。利用光学显微镜和原子力显微镜对玻璃阳模和PDMS基片表面形貌进行表征,研究了PDMS表面微纳结构化处理对抗体吸附能力的影响。结果表明:3D微纳结构的PDMS由于具有大的比表面积,能显著增强抗体的吸附能力。将研制所得的3D微纳表面结构的PDMS芯片用于微阵列荧光免疫分析,其灵敏度是平板PDMS的5倍。     

集成微流体测控芯片的研制

设计、研制了集成有微泵、微沟道、微流量传感器、温度传感器的微流体测控芯片.采用有限元软件ANSYS模拟分析了将其作为冷却芯片时微沟道的散热作用,分析确定了芯片上各元件的结构.该集成芯片为硅-玻璃结构,在硅片上,利用ICP法刻蚀无阀微泵泵体和微沟道;在7740玻璃片上,以溅射、剥离法制作微流量和温度传感器;图形精确对准后硅/玻璃以静电键合方法封接.无阀微泵采用压电元件驱动.测试结果表明:集成芯片具有冷却功能,循环水的流速最大可达25.4mm/s.     

玻璃缺陷检测新方法的研究

玻璃缺陷检测已成为提高玻璃质量的重要技术之一,它在检测出不合格玻璃产品的同时,还能将缺陷信息传递给玻璃生产的各个流程,再对各个环节加以改进。为能够生产出高质量的玻璃和准确地获取玻璃缺陷信息,采用了一种基于莫尔条纹的玻璃缺陷检测新方法。这种检测方法不但能够检测出微小缺陷,并进行分类,还能有效地检测出玻璃的光学畸变。     

微系统技术（连载二）—微系统采用的新材料

简要介绍了微系统技术中几种新材料，如液相外延硅，多晶硅、金刚石膜，新型玻璃，碳化硅薄膜的性能和制备方法。     

面向TGV衬底的玻璃回流的流动建模

在微机电系统(MEMS)圆片级封装工艺中,为了给制作玻璃通孔(TGV)衬底的玻璃回流工艺提供理论指导意见,提出并建立了一个玻璃回流通用模型,研究槽深、槽宽、温度、时间参数对玻璃回流的影响,并推导出在一定槽宽,槽深,温度下的玻璃在微细槽内流动长度随时间的变化关系.建立玻璃在微细槽内的数学流动模型,运用流体力学的知识,结合微细流体的特征,通过一系列理论分析、推导和简化运算,得出玻璃回流长度随时间等参数的理论变化公式.然后进行玻璃回流实验,当玻璃在恒温T0=800℃、槽宽2b =200 μm、槽深L=1000 μm时,观察并记录玻璃在微细槽内流动长度随时间的变化.将理论回流曲线与实验数据点进行对比,结果表明:实验回流曲线与理论回流曲线趋势一致,且数值基本相符.证明了理论模型及其分析过程的正确性.表明理论分析模型对TGV玻璃回流工艺参数可提供一定的理论指导.     

微系统技术（连载二）─微系统采用的新材料

简要介绍了微系统技术中几种新材料，如液相外延硅、多晶硅、金刚石膜、新型玻璃、碳化硅薄膜的性能和制备方法。     

一步法制备的ZnO-硼硅酸铅锌玻璃压敏电阻电性能研究

以四足状纳米ZnO粉末为原料,以制备硼酸铅锌玻璃的氧化物替代硼酸铅锌玻璃直接进行共烧结,制备出了ZnO-硼硅酸铅锌玻璃压敏电阻,并对其电性能进行了研究.研究结果表明:最佳添加量为13.0 wt%～17.4 wt%.当添加量在13.0 wt%～17.4 wt%时,在900～1 170℃温度范围,烧结温度对压敏电阻的漏电流IL和非线性系数α的影响很小.含13.0 wt%添加剂的样品,其最大非线性系数α和最小漏电流IL分别为38.7和1.7 μA.烧结温度的降低主要源自于纳米ZnO粉末和添加了硼酸铅锌玻璃"形成"氧化物.     

银改性玻璃表面荧光自组装膜的研制

利用离子交换结合热处理方法,制备出Ag纳米颗粒掺杂玻璃基底。通过荧光素分子和银之间的配位键合作用将荧光性分子组装在该玻璃基片上,构建一种新型的玻璃表面荧光性自组装单层膜的制备方法。运用吸收光谱讨论Ag纳米改性玻璃基底的最佳形成条件,并利用荧光吸收光谱考察了荧光素自组装单层膜的形成。实验结果表明在熔盐比例（摩尔比AgNO...     

普通硅酸盐样品中硼的电位法快速测定

目前,硅酸盐样品中硼的测定多采用酸碱滴定法或姜黄素比色法,由于这些方法受许多常见元素和成份的干扰,往往需要经预先沉淀分离或蒸馏分离,故操作繁琐,时间冗长。Robelt L.Kochen 曾报导用 BF~-选择电极测定硼硅玻璃中的硼,但是需经离子交换分离处理,操作亦较繁琐。本文研究了普通硅酸盐样品的分解及硼的测定条件,用     

A new fabrication method for borosilicate glass capillary tubes with lateral inlets and outlets

In this paper a new fabrication method for borosilicate glass capillary tubes is presented. As the interest in miniaturized total chemical analysis systems (μ-TAS) is increasing, the need for fluidic paths is growing and thus the study of microchannels, microtubes and microcolumns is an important topic of the microfluidic area. The capillary tubes presented here are fabricated by structuring and bonding three borosilicate glass wafers (7740 Corning Pyrex sR). Microchannels with lateral inlets and outlets have been successfully realized and well-defined size and shape have been obtained. Several capillary tubes with widths from 340 to 940 μm have been realized as well as different section shapes, which can be circular, elliptic or quasi-rectangular. The main fabrication steps and first characterizations are reported.     

低g值微惯性开关中阿基米德平面螺旋梁的设计

针对低g值微惯性开关对微弹簧的系统刚度达到(0.1~10)N/m数量级的要求,设计了一种阿基米德平面螺旋梁结构的微惯性开关。根据材料力学中的卡氏定理和线弹性理论,推导了阿基米德平面螺旋梁的弹性系数计算公式,并与ANSYS有限元仿真分析结果进行了对比。基于推导的弹性系数计算公式设计了一种三根阿基米德平面螺旋梁支撑的动作阈值5.5 gn 的微惯性开关,并采用SOI硅片以及玻璃－硅－玻璃键合技术进行了加工,在离心转台上对开关实际动作阈值进行测试,并将测试值与设计值进行对比。结果表明,采用推导到的阿基米德平面螺旋梁弹性系数计算公式计算结果与ANSYS仿真结果相近,基于推导的弹性系数计算公式设计的三根阿基米德平面螺旋梁支撑的微惯性开关动作阈值设计值与实测值相近,单根阿基米德平面螺旋梁弹性系数约0.8 N/m,能够满足低g值微惯性开关低刚度的要求,推导的弹性系数计算公式能够用于基于阿基米德平面螺旋梁的低g值微惯性开关的设计。     

Low cost anodic bonding for MEMS packaging applications

Anodic bonding of Pyrex 7740 glass to bare silicon and oxidized silicon wafer is presented for micro electro mechanical systems (MEMS) device packaging. Experimentally it has been observed that anodic bonding process parameters are varying with different 3D structures. The effects of bonding temperature and voltage are discussed by keeping the temperature constant and varying the voltage. The bonding interface has been studied by scanning electron microscope observations. Effective parameters for MEMS structure such as bonding temperature, voltage has been discussed.     

Microlens array fabrication by backside exposure using Fraunhofer diffraction

In UV-lithography, a gap between photoresist and UV-mask results in diffraction. Fresnel or near-field diffraction in thick positive and negative resists for microstructures resulting from a small gap in contact or proximity printing has been previously investigated. In this work, Fraunhofer or far-field diffraction is utilized to form microlens arrays. Backside-exposure of SU-8 resist through Pyrex 7740 transparent glass substrate is conducted. The exposure intensity profile on the interface between Pyrex 7740 glass wafer and negative SU-8 resist is modeled taking into account Fraunhofer diffraction for a circular aperture opening. The effects of varying applied UV-doses and aperture diameters on the formation of microlens arrays are described. The simulated surface profile shows a good agreement with the experimentally observed surface profiles of the microstructures. The paper demonstrates the ease with which a microlens array can be fabricated by backside exposure technique using Fraunhofer diffraction.     

Fabrication of silicon and oxide membranes over cavities usingion-cut layer transfer

Silicon and oxide membranes were fabricated using an ion-cut layer transfer process, which is suitable for sub-micron-thick membrane fabrication with good thickness uniformity and surface micro-roughness. After hydrogen ions were implanted into a silicon wafer, the implanted wafer was bonded to another wafer that has patterned cavities of various shapes and sizes. The bonded pair was then heated until hydrogen-induced silicon layer cleavage occurred along the implanted hydrogen peak concentration, resulting in the transfer of the silicon layer from one wafer to the other. Using this technique, we have been able to form sealed cavities and channels of various shapes and sizes up to 50-μm wide, with a 1.6-μm-thick silicon membrane. As a process variation, we have also fabricated silicon dioxide membranes for optically transparent applications     

Low-temperature anodic bonding of silicon to silicon wafers by means of intermediate glass layers

Silicon wafers have been anodically bonded to sputtered lithium borosilicate glass layers (Itb 1060) at temperatures as low as 150–180 °C and to sputtered Corning 7740 glass layers at 400 °C. Dependent on the thickness of the glass layer and the sputtering rate, the sputtered glass layers incorporate compressive stresses which cause the wafer to bow. As a result of this bowing, no anodic bond can be established especially along the edges of the silicon wafer. Successful anodic bonding not only requires plane surfaces, but also is determined very much by the alkali concentration in the glass layer. The concentration of alkali ions as measured by EDX and SNMS depends on both the sputtering rate and the oxygen fraction in the argon process gas. In Itb 1060 layers produced at a sputtering rate of 0.2 nm/s, and in Corning 7740 layers produced at sputtering rates of 0.03 and 0.5 nm/s, respectively, the concentration of alkali ions in the glass layers was sufficiently high, at oxygen partial pressures below 10^-4 Pa, to achieve anodic bonding. High-frequency ultrasonic microanalysis allowed the bonding area to be examined non-destructively. Tensile strengths between 4 and 14 MPa were measured in subsequent destructive tensile tests of single-bonded specimens.     

A high resolution MEMS based gas chromatography column for the analysis of benzene and toluene gaseous mixtures

his paper reports a high resolution gas chromatography (GC) column based on micro electro mechanical systems (MEMS) technology. This 6.0 m long, 100 μm wide, and 100 μm deep column was fabricated using deep reactive-ion etching (DRIE) to form channels for gas separation, and the channels were sealed with Pyrex 7740 glass by using anode bonding. After the GC column was coated with dimethyl polysiloxane (OV-1) as the stationary phase, benzene and toluene were successfully separated in less than 185 s. The resolution of benzene and toluene was 6.33, which was higher than any previously reported values to our best knowledge. The tailing factors of benzene and toluene were 1.13 and 1.20, respectively, and the number of theoretical plates of toluene was 4850. The system is applicable as a portable device for ambient air quality monitoring and industrial exhaust gas analysis.     

Micro structuring of borosilicate glass by high-temperature micro-forming

A new process technology is presented which allows the direct micro structuring of various glasses, especially bondable borosilicate glass (e.g. Pyrex^®7740), by means of forming at high temperatures with a micro-structured tool. The technology and fabrication equipment are described on the basis of a molded demonstration structure, and possibilities for application and transfer to industrial manufacturing are shown.     

Deep microstructuring in glass for microfluidic applications

Glass is widely used as a structural and functional material in micro-total-analysis-systems. Two low-cost techniques have been used to produce deep and vertical microstructures into glass. A commercially available photosensitive glass (Foturan™) is patterned by photolithography and etched in an HF solution for the construction of a microfluidic component. Channels and reservoirs were bonded to a poly(dimethylsiloxane) cover. A two-level structure with various depths (reservoirs and channels) was also made by a double exposure through two different masks. The other technique uses micro-ultra-sonic machining to form channels by erosion into borosilicate glass (Pyrex 7740). The two structuring techniques are compared with respect to surface profiles and surface states.     

Lithography with UV-LED array for curved surface structure

The technology to fabricate high-aspect ratio and micro curved surface structures is needed for optical device fabrication such as micro lens, light guiding device, and so on. In this study, micro curved surface structures were fabricated by using novel lithography technique with UV-LED array and rotary stage (Hanai et al. in Proceedings of the 22nd sensor symposium, pp 516–519, 2005). Smooth surface structures can be fabricated in this technique, because UV-LED which has wide directivity characteristics makes the difference of the UV dose. In addition, the structures can be formed with high uniformity in large area by only one exposure process, because rotation reduces the unevenness of exposure. This technique can control the shapes of structures by changing exposure time and applying gray scale mask method (Waits et al. in Sensors Actuat A 119:245–253, 2005). We fabricated structures of hemisphere, semi-cylinder, and semi-cone by using this technique. High-aspect ratio structures were obtained and they had smooth curved surface. Then, they were used for micro lens fabrication. By using molding technique, micro lenses of the UV curable resin were fabricated on the silicon wafer.