一种基于HTCC的高隔离度开关电路设计

基于开关芯片实现的开关电路是射频前端的基本单元之一,其功能是实现射频信号的导通和关断,在小功率射频信号传输中应用广泛。本文以6 GHz～15 GHz超宽带、60 dB隔离度为设计目标,采用高温共烧陶瓷基板工艺和级联腔体隔离技术,以级联开关芯片为基本电路结构,设计了高隔离度开关电路。该电路包含一只限幅器和两只吸收式砷化镓单刀单掷开关,装配于两个相邻的隔离腔体结构中,通过类同轴垂直传输过渡到基板内对称带状线传输结构,再辅以两侧地孔,实现电磁屏蔽。对开关电路进行电磁场建模仿真,结果表明该结构具有良好的传输特性和隔离特性;在射频前端电路制造完成后对开关电路进行装配和测试,测试结果与建模仿真结果一致性高,验证了本文设计的开关电路具有高隔离度特性。     

在SOI基上设计实现D/A驱动的高压LDMOS开关电路

设计实现SOI基上带有D/A驱动的高压LDMOS功率开关电路,利用D/A变换的灵活性,运用数字电路与高压模拟电路混合设计方法,实现数字控制的耐压为300V的LDMOS功率开关电路．该功率集成电路芯片的实现,为SOI高压功率开关电路提供了一种更为方便快速的数字控制设计方法,同时也为功率系统集成电路提供了一种有效的实验验证,从而证实了功率系统集成的探索在理论上以及工程上具有一定的可行性．     

在SOI基上设计实现D/A驱动的高压LDMOS开关电路

设计实现SOI基上带有D/A驱动的高压LDMOS功率开关电路,利用D/A变换的灵活性,运用数字电路与高压模拟电路混合设计方法,实现数字控制的耐压为300V的LDMOS功率开关电路.该功率集成电路芯片的实现,为SOI高压功率开关电路提供了一种更为方便快速的数字控制设计方法,同时也为功率系统集成电路提供了一种有效的实验验证,从而证实了功率系统集成的探索在理论上以及工程上具有一定的可行性.     

基于硫系玻璃的光学被动式红外无热化镜头设计

研究了一种锑化铟红外焦平面器件盲元分析方法,即无需将器件背面减薄就可进行盲元测试与分析。用该封装装配方式将器件倒置,实现从芯片正面吸收光的照射。在完成互连、灌胶以及每一步磨抛工艺步骤后,都可以进行测试和分析。结果表明,该方法能够有效地分析和定位每步工序过程中产生的盲元情况,解决了现有技术手段中对红外焦平面器件因产生盲元导致像元失效无法准确定位出现在哪步工艺的问题。     

QFN芯片表面划痕检测定位方法设计

在工业应用中,需要对方形扁平无引脚封装(Quad flat no-lead package, QFN)芯片表面划痕实时 准确检测,提出了一种快速的芯片表面划痕检测定位方法。通过图像分割算法获取缺陷图像,结合 轮廓提取算法可以较好地实现芯片表面划痕定位。同时,为了保证对芯片表面划痕实时检测,采用 基于粒子群的Otsu多阈值算法进行图像分割,不仅使得图像中缺陷区域更加明显,而且缩短了芯片 表面划痕检测时间。与直接采用Otsu算法相比,芯片表面划痕检测时间由秒级缩短至毫秒级,提高 了芯片质量检测效率。该划痕快速定位检测方法对芯片检测设备软件系统开发与应用具有重要的参考价值。     

基于FPGA的RFID晶圆并行测试系统设计

针对高频射频识别(RFID)晶圆在中测(CP)阶段单通道串行测试效率低下的问题,设计了一种基于现场可编程门阵列(FPGA)的多通道并行测试系统以提高测试效率.鉴于RFID晶圆上没有集成天线,提出了一种新的基于探针技术的射频耦合式的晶圆检测方法,模拟芯片实际工作.系统选用FPGA为微控制器,配以多路射频耦合通信电路,实现测试向量生成及快速信号处理.再结合上位机与探针台高速并行的通用接口总线(GPIB)通信接口,以实现晶圆级RFID芯片测试.经实际测试,该系统能够实现16通道并行测试,与单通道串行测试系统相比,效率提升了97％,可靠性好,稳定性高,可应用高密度RFID晶圆的中测.     

基于物理版图信息的低功耗扫描测试方法

芯片测试模式下功耗过高的情形会极大地降低芯片良率,已经成为越来越严重的问题。针对此问题,本文提出了一种降低测试功耗的设计方法。该方法采用贪婪算法来改变扫描链顺序,同时考虑芯片物理版图中寄存器单元的具体位置,能够实现在不影响测试覆盖率和绕线的前提下,快速有效地降低测试功耗。与已有的多种方法相比,该方法更快速更合理,可以应用于多种芯片的扫描链设计。该方法通过一款实际的电力线载波通信芯片验证,分别将平均功耗和瞬态功耗降至77%和83%。     

基于机器视觉的表贴芯片缺陷检测系统研究

基于表贴芯片缺陷检测的需要,设计了一种基于机器视觉的表贴芯片缺陷检测系统,并对该系统的硬件和软件部分作了简要介绍,重点研究了芯片的引脚边缘检测算法,在此基础上实现了芯片长度、宽度和间距等特征参数的提取。测试结果表明,该检测系统能达到在线生产的工艺要求。     

一种用于三相无刷直流电机驱动的软开关电路

提出了一种用于三相无刷直流电机(BLDCM)驱动芯片的软开关电路。利用提出的控制电路,实现了输出换相切换时的平稳过渡。该软开关控制电路在驱动相进入驱动状态或退出驱动时起作用,实现了驱动或退出驱动的平稳过渡,有效抑制电机换相时负载线圈上的电流波动及发热,实现了换相转动力矩的平稳切换。该控制电路完全集成于电机驱动芯片内部,不使用外部元件和引脚。通过UMC 0.6μm 5V2P3MBiCMOS工艺,对电路进行流片验证。芯片样品测试结果表明,该软开关控制电路可实现驱动换相的平稳切换。     

基于ESD的芯片失效分析

提出了一种基于静电放电（ESD）的芯片可靠性测试及失效分析流程,并且以芯片静电放电测试为例详细阐述了芯片失效分析的过程与实现方法,包括电性失效分析和物理失效分析。通过专用仪器对芯片进行了静电放电测试,并利用红外微光显微镜（EMMI）及砷化镓铟微光显微镜（InGaAs）等实现芯片故障定位,从而确定芯片的失效模式与失效机理,实验证明该方法切实有效,这种失效分析的结果对优化集成电路的抗静电设计以及外部工作环境的完善都具有重要的参考意义。     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.