MEMS兼容丝网印刷PZT压电厚膜研究

对丝网印刷PZT压电厚膜制备工艺浆料配置、印刷技术、退火条件、上下电极的选择及极化方法等进行了研究,并采用扫描电子显微镜(SEM)及与之配套的能谱分析仪对制备的PZT样品的微观结构、成分进行了测试分析.结果表明,PZT压电厚膜的膜厚可达100μm,印制图形分辨率在500μm以上,在800℃经1h退火就可获得良好的微晶结构,且具有压电特性.     

流延硅基PZT厚膜工艺研究

研究了基于流延技术制备硅基锆钛酸铅（PZT）厚膜的工艺。考虑衬底特性对厚膜品质的影响,在不同的种子层上分别制备了PZT厚膜,测试工艺结果,证实了种子层的作用。分析了高温烧结时间对流延PZT厚膜品质的影响,确定了最优高温烧结时间。文章提出的硅基PZT厚膜工艺可用于制备射频天线的介质基片。     

MEMS兼容丝网印刷PZT压电厚膜研究

对丝网印刷PZT压电厚膜制备工艺浆料配置、印刷技术、退火条件、上下电极的选择及极化方法等进行了研究，并采用扫描电子显微镜(SEM)及与之配套的能谱分析仪对制备的PZT样品的微观结构、成分进行了测试分析。结果表明，PZT压电厚膜的膜厚可达100μm，印制图形分辨率在500μm以上，在800℃经1h退火就可获得良好的微晶结构，且具有压电特性。     

MEMS兼容丝网印刷PZT压电厚膜研究

对丝网印刷PZT压电厚膜制备工艺浆料配置、印刷技术、退火条件、上下电极的选择及极化方法等进行了研究 ,并采用扫描电子显微镜 (SEM )及与之配套的能谱分析仪对制备的PZT样品的微观结构、成分进行了测试分析。结果表明 ,PZT压电厚膜的膜厚可达 10 0 μm ,印制图形分辨率在5 0 0 μm以上 ,在 80 0℃经 1h退火就可获得良好的微晶结构 ,且具有压电特性     

用于能量收集器的不锈钢基PZT厚膜制备研究

采用了溶胶 凝胶技术在不锈钢基体上制备了厚为10 μm、结构致密的锆钛酸铅(PZT)厚膜。研究了不同退火条件对厚膜结晶状况的影响,X射线衍射分析表明,采用700 ℃退火处理20 min后得到了PZT厚膜的纯钙钛矿相结构。厚膜的电学性能测试结果显示,厚膜的剩余极化强度（Pr）为7.5 μC/cm2, 矫顽场强（Ec）为7.2 V/μm,压电常数（d33）为73 pC/N。设计制作了长20 mm、宽4 mm的压电悬臂梁结构振动能量收集器。输出性能测试结果显示,振动频率为95 Hz,采集器输出电压最高,输出电压值为862 mV。     

PZT叠层厚膜陶瓷材料性能的研究

使用凝胶流延成型工艺制备了PZT85/15、PZT95/5单组分厚膜及叠层厚膜.通过和单组分厚膜的性能进行对比,分析了叠层厚膜的形貌特征及介电、铁电和热释电性能.结果表明,由PZT85/15和PZT95/5组成的叠层厚膜内部均匀致密,具有良好的介电、铁电和热释电性能,极化后的相对介电常数εr=191.5,介电损耗tan δ=0.7%(温度T=20℃,频率f=1 kHz),热释电系数在41℃时达到峰值8×10-8 C/cm2·K,此后下降不明显,从而改善了单组分厚膜相变温区过窄的缺点,达到拓宽相变温区的目的,有望在红外探测和相变换能方面得到更广泛的应用.     

MEMS微拾振器制备工艺研究

采用微机电系统(MEMS)技术制作了悬臂梁式压电微拾振器,该技术主要包括:sol-gel法制备PZT压电膜、干法刻蚀、湿法化学刻蚀、UV-LIGA等工艺。研制的拾振器悬臂梁结构尺寸为:长2000μm,宽600μm,硅膜厚度12μm,PZT压电膜厚1.5μm,Ni质量块长600μm、高500μm。测试表明其固有频率为610Hz,适合低频振动源环境的应用。在1gn加速度谐振激励下,电压输出达562mV。     

纳米级PZT颗粒制备及压电性能检测

对微米级锆钛酸铅(PZT)粉体的无水乙醇溶液进行兆赫超声处理,制备PZT纳米颗粒,将试样滴于蒸金硅片上并进行烘干处理,采用压电力显微镜观测其尺寸、表面形貌及纵向压电系数.试验结果表明,试样中微米级PZT颗粒的纵向压电系数在20～40 pm/V上下浮动,纳米级PZT颗粒纵向压电系数在2～10 pm/V上下浮动,均具有压电性能.该方法为制备厚膜压电器件提供了一种可行的技术途径.     

低声阻抗0—3型PZT/PT/PVDF压电复合材料的研制

压电陶瓷材料的高声阻抗制约着其在水听器和超声成像方面的应用。为了对压电陶瓷材料的声阻抗和声速进行调节,本研究以聚偏氟乙烯(PVDF)及钛酸铅(PT)和锆钛酸铅(PZT)压电陶瓷粉体为原料,经过流延、热压等工艺制得了4种含有不同量PT及PZT的0—3型PZT/PT/PVDF压电复合材料。研究了所制压电复合材料的声学、压电和介电性能。结果表明:所制压电复合材料的声阻抗均小于140 MPa.s/m,最优压电应变常数d33达43 pC/N,相对介电常数为185～210,介质损耗约为2×10–2。     

PZT铁电厚膜声纳换能器

综述了 PZT厚膜单元声纳换能器和 8× 8阵列声纳换能器的制备方法、结构和性能 ,并介绍了 PZT厚膜声纳换能器的应用及发展前景。该厚膜是利用改进的 sol- gel工艺制备的 ,厚度为 4～ 12 μm。4μm厚的 PZT厚膜的纵向压电系数 d3 3 为 140～ 2 40 p C/ N,剩余极化强度 Pr为 2 8× 10 - 6 C/ cm2 ,矫顽场强 EC为 30× 10 3 V/ cm,相对介电系数 εr为 140 0。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.