微机电系统扭转微镜面驱动器的研制

提出了一种新颖的采用键合减薄工艺制作的微机电系统扭转微镜面驱动器,该种微镜面驱动器工艺制作简便可行.通过对研制的微镜面驱动器进行测试,该驱动器在18V驱动电压时可以达到0.3°的扭转角度,微镜面的频率响应时间小于1ms.同时该驱动器具有较大的微反射镜面,面积达到600μm×700μm,试验结果表明微镜面驱动器将可以应用于光通信领域.     

MEMS微电磁驱动器磨损对光开关性能的影响分析

光开关中运动元件的磨损对光学元件的位置精度有重要影响。介绍了MEMS微电磁驱动器磨损对光开关光学性能影响的理论分析,采用光纤光学理论计算了磨损所引起的光开关的附加插入损耗,结果表明,所采用的微电磁驱动器磨损引起的附加插入损耗小于0.02 dB,其磨损特性可以满足光通信开关的要求,实验结果证明了理论分析的正确性。此方法对光开关和MEMS微驱动器的研究具有指导意义。     

MEMS微电磁驱动器的分段磁路模型及实验研究

介绍了一种MEMS电磁微驱动器.基于分段磁路的网络方程法,针对微电磁驱动器所采用的平面线圈的结构特点,建立了平面线圈微驱动器的非线性磁路模型.实验结果表明,考虑线圈绕组半径不同而产生的磁动势分布效应可以为平面线圈型微驱动器建立可靠的模型.采用硅微细加工技术和微电铸技术成功地制作出了这种微驱动器,并对器件的性能进行了测试,测试结果表明,该模型能很好地计算驱动器的电磁力.     

微型电磁驱动器中微小电磁力的研究

设计了一种应用于微机电系统中的微型电磁驱动器。该微驱动器主要由平面正方形线圈、弹性支撑和坡莫合金薄片构成。采用微细加工技术成功地制作出了这种微驱动器。该驱动器具有较大的驱动力和行程，适用于垂直方向上需求较大偏转的微机电系统中。研究了平面线圈对坡莫合金磁体的微小作用力，并用有限元模拟软件ANSYS，对该作用力进行了模拟分析。     

一种新型并联梳齿驱动的静电型微继电器

介绍了一种新型的、利用并联梳齿结构驱动的静电型微继电器及其制造工艺。通过优化并联梳齿结构的几何尺寸,可以使微继电器的阈值电压降低到5V。该微继电器的主体部分使用一套表面牺牲层标准工艺制造,同时,使用溅射工艺制作Au接触电极,可以使接触电阻降到100mΩ以下,增加了微继电器的使用寿命。由于该微继电器的驱动电压和制造工艺都和普通集成电路的驱动电压和制造工艺相兼容,因此两者在产业化生产中可以很容易地被集成在同一芯片上。     

一种新型并联梳齿驱动的静电型微继电器

介绍了一种新型的、利用并联梳齿结构驱动的静电型微继电器及其制造工艺。通过优化并联梳齿结构的几何尺寸，可以使微继电器的阈值电压降低到5V。该微继电器的主体部分使用一套表面牺牲层标准工艺制造，同时，使用溅射工艺制作Au接触电极，可以使接触电阻降到100mΩ以下，增加了微继电器的使用寿命。由于该微继电器的驱动电压和制造工艺都和普通集成电路的驱动电压和制造工艺相兼容，因此两者在产业化生产中可以很容易地被集成在同一芯片上。     

具有光纤自定位保持结构的2×2扭转微镜光开关阵列的制作和机电特性

应用基于表面硅、体硅微电子工艺的混合微加工技术,制作了新型2×2扭转微镜光开关阵列,并研究了其在外加静电场和交变电场中的机电特性.当该光开关中悬挂多晶硅微镜的弹性扭转梁的厚度约为1μm时,驱动微镜以实现其"开"状态的拐点静电电压为270～290V,而维持微镜"开"状态的最低保持电压在55V左右.理论分析表明,在关于该光开关结构的一系列设计参数中,拐点静电电压对于弹性扭转梁的厚度最敏感.该光开关的开关寿命超过108次,而其开关时间预计小于2ms.对单片集成制造在该光开关阵列芯片上的两种新型光纤自定位保持结构的力学分析表明,它们具有光纤自固定、自对准的性质.     

具有光纤自定位保持结构的2×2扭转微镜光开关阵列的制作和机电特性

应用基于表面硅、体硅微电子工艺的混合微加工技术,制作了新型2×2扭转微镜光开关阵列,并研究了其在外加静电场和交变电场中的机电特性.当该光开关中悬挂多晶硅微镜的弹性扭转梁的厚度约为1μm时,驱动微镜以实现其"开"状态的拐点静电电压为270～290V,而维持微镜"开"状态的最低保持电压在55V左右.理论分析表明,在关于该光开关结构的一系列设计参数中,拐点静电电压对于弹性扭转梁的厚度最敏感.该光开关的开关寿命超过108次,而其开关时间预计小于2ms.对单片集成制造在该光开关阵列芯片上的两种新型光纤自定位保持结构的力学分析表明,它们具有光纤自固定、自对准的性质.     

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。     

一种新型并联梳齿驱动的静电型微继电器

介绍了一种新型的、利用并联梳齿结构驱动的静电型微继电器及其制造工艺.通过优化并联梳齿结构的几何尺寸,可以使微继电器的阈值电压降低到5V.该微继电器的主体部分使用一套表面牺牲层标准工艺制造,同时,使用溅射工艺制作Au接触电极,可以使接触电阻降到100 mQ以下,增加了微继电器的使用寿命.由于该微继电器的驱动电压和制造工艺都和普通集成电路的驱动电压和制造工艺相兼容,因此两者在产业化生产中可以很容易地被集成在同一芯片上.     

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.     

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.     

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.     

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.     

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.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

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.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.