工作条件下超声倒装键合换能系统的阻抗特性

在建立各子部分等效阻抗的基础上,采用等效电路方法构建工作条件下芯片超声倒装键合换能系统的阻抗/导纳模型.对阻抗模型进行数值计算,并采用频率扫描的方法实测系统的阻抗特性.研究发现,在工作条件下,换能系统100 kHz范围内包含4阶轴向固有频率;相比于空载条件,工作条件下的各阶谐振频率增大,其电阻值增大,电导值降低.实验测试与数值计算结果相互吻合.     

铸造用超声换能系统阻抗模型的研究

利用等效电路建立了铝合金铸造用超声换能系统的阻抗模型,在15～28 kHz范围内分析了常温和铸造条件下系统纵振频率和阻抗。在常温和铸造条件下,系统分别有2、3阶纵振频率;在铸造条件下,1阶频率对应的阻抗增加明显。利用Agilent4294A阻抗分析仪做了扫频测量,结果与此相符。     

夹持环对换能系统振动模态影响的有限元分析

换能系统是热超声引线键合装备的核心部分,夹持环对系统起安装支撑的作用,其安装方式直接影响换能系统的能量传递与振动模态。利用有限元法分析了夹持环对换能系统振动模态的影响,结果表明,对夹持环未施加约束、施加z向约束时换能系统的夹持环会出现振动现象,而施加x向约束时,工作频率下的主振型完全不符合要求;改变夹持环的安装位置,对换能系统的节点位置及谐振频率都有一定的影响,实验测得在全约束情况下,换能系统的节点位置为58 mm,与分析结果一致;换能系统在工作频率附近包含有其他的振动模态,在键合过程中易被激发出来,由此消耗超声能量而降低芯片的键合质量,这些振动模态必须得到抑制。     

基于有限元模型的超声切割刀优化设计

超声切割刀在材料加工领域中有广泛的应用前景,可用于切割各种复合材料等硬脆材料。该文利用ANSYS有限元分析软件建立超声切割刀的有限元模型,对其进行模态分析和谐响应分析。仿真结果显示,超声切割刀在40 kHz频率附近存在轴向纵振模态,其振动节点位于安装环和压电陶瓷中心线上,符合设计要求。基于有限元模型研制超声波切割刀,通过阻抗分析仪与激光多谱勒测振仪对换能器的固有频率与响应进行测试,获得的超声切割刀阻抗曲线平滑,谐振频率为40.261 kHz,设计误差为0.83%,最大振幅达到14.52 μm,结果与有限元计算相互吻合。     

基于有限元模型的超声切割刀优化设计

超声切割刀在材料加工领域中有广泛的应用前景,可用于切割各种复合材料等硬脆材料。该文利用ANSYS有限元分析软件建立超声切割刀的有限元模型,对其进行模态分析和谐响应分析。仿真结果显示,超声切割刀在40kHz频率附近存在轴向纵振模态,其振动节点位于安装环和压电陶瓷中心线上,符合设计要求。基于有限元模型研制超声波切割刀,通过阻抗分析仪与激光多谱勒测振仪对换能器的固有频率与响应进行测试,获得的超声切割刀阻抗曲线平滑,谐振频率为40.261kHz,设计误差为0.83%,最大振幅达到14.52μm,结果与有限元计算相互吻合。     

超声拉拔振动系统研究

根据传统解析法、四端网络和有限元分析法综合设计了超声拉拔振动系统,利用有限元软件ANSYS对振动系统进行了模态分析和谐响应分析,得到了振动系统的振型、谐振频率和振幅放大系数。利用阻抗分析仪和工具显微镜对振动系统进行了测试。实验结果表明,理论设计、分析与实际情况符合良好,且此振动系统在超声拉拔实验中正常工作。     

劈刀安装对换能系统性能的影响

通过采用F&K超声检测系统检测劈刀的安装方式对超声换能系统的性能影响,从最基本的实验数据(谐振频率,相位及阻抗)出发,分析劈刀引起换能系统的非线性特性,为设备工艺窗口参数调节提供理论基础。     

汽油超声喷嘴的设计研究

为了进一步细化汽油雾化粒径,该文基于一维振动理论研究设计了一种汽油超声喷嘴。采用有限元法分析振动模态和谐响应,获得其谐振频率、振动位移与工作应力分布,理论频率30.157 kHz与HP 4286A LCR精密阻抗测试仪实测频率30.862 kHz接近。此外,对超声喷嘴的汽油雾化效果进行了理论计算分析与试验研究,理论计算粒径24.38 μm,实测粒径27.62 μm,两者基本一致,比传统汽油喷油嘴的雾化粒径(约50 μm)缩小约2倍。研究结果有效地改善了汽油的雾化质量,提高了燃油利用率。     

汽油超声喷嘴的设计研究

为了进一步细化汽油雾化粒径,该文基于一维振动理论研究设计了一种汽油超声喷嘴。采用有限元法分析振动模态和谐响应,获得其谐振频率、振动位移与工作应力分布,理论频率30.157kHz与HP-4286A LCR精密阻抗测试仪实测频率30.862kHz接近。此外,对超声喷嘴的汽油雾化效果进行了理论计算分析与试验研究,理论计算粒径?24.38μm,实测粒径?27.62μm,两者基本一致,比传统汽油喷油嘴的雾化粒径(约?50μm)缩小约2倍。研究结果有效地改善了汽油的雾化质量,提高了燃油利用率。     

键合工具对超声换能器系统谐振频率的影响

建立了超声引线键合机换能器系统振动分析有限元模型,利用ANSYS软件分析了换能器系统与键合工具组成的纵-弯复合振动系统的振动特性。计算结果表明,键合工具的弯曲振动与换能器系统纵向振动存在耦合关系,劈刀长度增加50%将使换能器系统谐振频率下降5.6%;实验中测试了换能器系统的阻抗与导纳特性,发现当劈刀长度为16 mm时系统的阻抗匹配较为理想;换能器系统的谐振频率的实测值与有限元分析结果一致,最大误差为3.51%。     

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.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

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.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

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.     

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.