压电基片上集成微通道数字微流体微混合器研究

微流体在压电基片上输运往往偏离声表面波传播方向,尤其是当压电基片表面疏水层不很均匀时,给微流体诸如混合等操作带来不便。在1280旋转Y切割X传播方向的LiNbO3基片上研制了集成有聚二甲基硅氧烷为材料T型微通道的微混合器,压电基片上采用光刻工艺制作相互垂直叉指换能器及反射栅。待混合的两微流体采用微量进样器分别进样到声路径微通道中,依次在两叉指换能器上加RF电信号,它激发的声表面波驱动其声路径上微通道中的微流体沿微通道输运、合并,并快速混合。对2μl水-2μl蓝色染料微流体和2μl甘油-2μl蓝色染料微流体进行混合实验,结果表明,声表面波的作用可以提高微通道中微流体的混合速度,且混合程度更高。     

基于声表面波技术的数字微流体微加热器研究

设计了在128°旋转Y切割X传播方向LiNbO3基片上研制了数字微流体微加热器。它由压电基片上两个叉指换能器构成,当由功率放大器放大后的射频电信号加到叉指换能器时,其激发的声表面波经微流体后转化为径向表面波,并辐射入微流体达到加温效果。停止加电信号后,微流体能量向外界辐射迅速降温。采用2μL的甘油微液滴进行升温实验,结果表明:微流体温度变化由外加电信号强度和持续时间决定,在电信号强度为19V时,微流体的温度上升速率为1.5℃/s,与理论6.2℃/s结果基本相符。     

基于声表面波微通道内微液滴选择性输运研究

提出了声表面波实现微通道内微液滴选择性输运的方法,并研制了相应的微器件。它包括128°YXLiNbO3基片上光刻有两叉指换能器的压电子器件、微隔板和聚二甲基硅氧烷微通道。通过软光刻工艺制作聚二甲基硅氧烷微通道,采用内嵌塑料薄片微隔板,将微通道分割为两分支微通道,并贴合于压电基片上。叉指换能器激发的声表面波结合进样器进样的石蜡油驱使待输运微液滴向目标分支微通道运动,实现微通道内微液滴选择性地输运到目标分支微通道。以水液滴为研究对象,进行了微液滴选择性输运实验,结果表明,声表面波可以实现微通道内微液滴选择性输运到目标分支微通道,从而为压电微流器件进行微流分析提供前提条件。     

声表面波跨越式输运数字微流体

研究了声表面波实现数字微流体在压电基片上跨越障碍物的方法。在128°-YX-LiNbO3压电基片上采用微电子工艺制作了中心频率为25.5 MHz的叉指换能器和反射栅,在声传播路径上涂覆Teflon AF 1600疏水薄膜,聚二甲基硅氧烷垫块贴合于压电基片上。经功率放大器放大的射频信号加于叉指换能器激发声表面波,并作用在声路径上的数字微流体,在其内产生声流,当瞬间减少射频信号功率,部分液体因惯性力大于表面张力而飞离微流体,跃过聚二甲基硅氧烷障碍物,实现在压电基片上跨跃障碍输运。采用油包红色染料溶液微流体进行了实验,结果表明,当射频信号功率从12.3 dBm瞬间下降到-3.98 dBm时,油包红色染料溶液微流体可跃过高度1 mm的障碍物。     

基于声表面波技术数字微流体微混合器研究

报道了在128°旋转Y切割X传播方向LiNbO3基片上研制了数字微流体微混合器.它由压电基片上叉指换能器和反射栅组成,当由功率放大器放大后的射频电信号加到叉指换能器时,它激发的声表面波经微流体后转化为径向表面波驱动微流体,使其与同一路径上的另一微流体合并,在反射栅反射回的声表面波共同作用下,加速微流体内分子扩散运动,提高了微流体混合效率.采用1 μL的水和1 μL红墨水以及1 μL的红墨水和1 μL甘油各自进行混合实验,结果表明:在声表面波作用下,微混合器能快速混合微流体.为片上实验室提供了廉价、易集成的微混合单元,具有潜在的应用价值.     

阵列式芯片特定区域内微流体加热研究

提出了阵列式芯片特定区域内微流体的加热方法,研制了4×4阵列式聚二甲基硅氧烷芯片及其特定区域的加热组件。在128°YX-LiNbO3基片上光刻16个叉指换能器,其激发的SAW驱动压电基片上油相流体,使其输运到待加热区的传热柱上,在油相流体两侧的叉指换能器上加电信号,激发SAW加热油相流体,并通过传热柱加热阵列式芯片受热区内微流体。以石蜡油微流体为实验对象进行阵列式芯片特定区域微流体加热实验,结果表明,SAW可有效加热阵列式芯片特定区域内石蜡油微流体,在30.0dBm电信号功率作用下,使7.5μL石蜡油温度从22.3℃上升到33.5℃。     

基于声表面波技术实现微流体数字化

微流体的数字化是压电微流控芯片进行微流分析的前提,提出了采用声表面波(SAW)实现微流体数 字化的方法.在128°YX-LiNbO3基片上研制了中心频率为27.7 MHz的叉指换能器,在压电基片上方固定一细针,它经由Teflon软管与注射泵相连,注射泵提供恒定流量的微流体到达细针孔端并聚集,当聚集的微流体高度达到细针孔端与压电基片间距时,叉指换能器激发的声表面波驱动微流体实现微流体数字化.提出了计算细针孔端与压电基片间距的方法和微流体实现数字化的条件.以水为实验对象进行数字化实验,结果表明,声表面波作用下能实现微流体数字化,为压电微流控芯片提供了一种新的微流体引入方法.     

基于声表面波油包水微液滴分裂研究

提出了声表面波(SAW)实现油包水微液滴的分裂方法,并在128°YX-LiNbO3基片上研制了分裂油包水微液滴的微器件。在压电基片上采用微电子工艺制作叉指换能器,其激发的SAW部分作用于油包水微液滴,瞬间降低电信号幅度,油相内水微液滴在惯性力作用下发生分裂,油相微液滴由于较大的表面张力发生形变而不分裂。以石蜡油包裹蓝色水相微液滴为研究对象,进行了油包水微液滴分裂实验和理论分析,结果表明,当电信号从功率为12.3dBm瞬间关断时,可实现油相内水微液滴分裂。     

基于声表面波纸基微流器件研究

研制了压电基片上能实现样品前处理的纸基微流器件.在128°YX-LiNbO3基片上制作了1个叉指换能器和1个反射栅;亲水性纸用来制作微流器件的微通道,浸有指示剂滤纸作为微反应器,一同粘附于透明胶带上,并采用聚二甲基硅氧烷(PDMS)贴合于压电基片上.叉指换能器激发的声表面波驱动压电基片上的样品,使其输运到纸基微通道,并在纸基微反应器进行微流分析.在研制的纸基微流器件上实现了NO2-浓度的快速检测.     

基于声表面波技术实现微通道内微流体的融合

提出了一种新的油相微通道内微流体融合方法.在128°YX-LiNbO3基片上光刻叉指换能器(IDT)和反射栅,模塑法制作的聚二甲基硅氧烷(PDMS)微通道贴合于压电基片的声路径上,在PDMS微通道内采用微量进样器注入石蜡油和待融合微流体.经功率放大器放大后的射频(RF)电信号加到IDT上,激发声表面波(SAW),驱动微通道内的待融合微流体,实现其融合.实验结果表明,在SAW作用下,微通道内微流体的融合决定于加到IDT上RF信号功率、待融合微流体直径和待融合微流体间距.     

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.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

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.