铝合金箔片封装光纤光栅传感特性研究

针对表面粘贴式光纤光栅(FBG)传感器存在的封装体积过大、粘接不便的问题,提出一种光纤光栅的铝合金箔片封装工艺,并通过悬臂梁加载实验和水浴加热法对封装后光纤光栅的应变与温度传感特性进行了实验研究.测试结果表明,经铝合金箔片封装后的光纤光栅传感器与裸光纤光栅相比较,应变灵敏度提高了1.2倍,达到1.407 pm/με,温度灵敏度提高了3.02倍,达到29pm/℃,中心波长的漂移与荷载及温度都具有良好的线性关系,且有较好的重复性.     

金属化封装光纤光栅传感器超低温特性研究

传统胶封光纤光栅(Fiber Bragg Grating,FBG)传感器的胶黏剂在超低温环境中存在着板结、与基体间热失配等问题。针对胶封光纤光栅传感器在超低温条件下进行测量的局限性,本文设计一种全金属化封装结构,并采用超声焊接的方法将光纤光栅封装固定于特种铝合金基底表面。在-160～0 ℃环境下,对两支FBG温度传感器的超低温传感特性进行了实验测试。结果表明,该封装形式的FBG传感器的线性度较好,相关系数均在0.99以上。它们的温度灵敏度系数在线性变化区间平均值分别为27.88 pm/℃和26.17 pm/℃,分别是封装前裸光纤光栅的2.75倍和2.58倍左右,提高了温度灵敏度。此金属化封装的FBG温度传感器的工艺简单,易于实现,可用于超低温恶劣环境下的温度测量。     

CO2激光刻写长周期光纤光栅与光纤MZ结构的双参数传感特性

为了实现温度与应变的双参数高精度传感测量,提出了一种CO2激光刻写长周期光纤光栅（Long Period Fiber Grating,LPFG）与光纤马赫-增德尔（MZ）干涉型结构的光纤传感器,利用CO2激光刻写制作LPFG并利用错位熔接法制备光纤MZ结构,将二者级联并实时监测温度及应变变化时的透射谱变化,研究了其传感原理并验证了其温度及应变传感特性。实验结果表明:该双参数光纤传感器的LPFG仅对温度敏感,MZ干涉结构对温度和应变都敏感;在温度范围35~70℃时,LPFG特征波长升温灵敏度38.57 pm/℃,降温灵敏度39.17 pm/℃;MZ干涉结构特征波长升温灵敏度38.57 pm/℃,降温灵敏度为37.50 pm/℃;当应变范围0~450 时,MZ干涉结构加载灵敏度4.01 pm/,卸载灵敏度为4.24 pm/。为温度和应变的实时测量提供了一种灵敏度高、线性度好的光纤传感器。     

卫星镜头结构光纤光栅温度传感器研究

为了解决卫星星敏感器光学镜头结构在轨温度监测问题,提出一种弧形基底封装的光纤光栅温度传感器。分析了星敏镜头结构特征与光纤光栅温度传感原理,采用飞秒激光刻写的光纤光栅作为敏感元件,设计了可贴合于星敏镜头结构特征的弧形封装基底,完成了光纤光栅温度传感器封装,并对传感器进行了拉伸测试、温度标定及温度重复性测试,并已应用于实际工程中。结果表明:弧形封装结构形式的光纤光栅温度传感器线性度可达0.998,温度灵敏度达到8.54 pm/℃,同一温度下中心波长变化量在2 pm以内,且受弧形基底封装结构变形产生的应变影响小。卫星在轨温度监测,光纤光栅传感与电子式传感相差±3 ℃。可以实现星敏镜头结构的温度测量功能,在星敏感器结构在轨温度测温中具有应用前景。     

一种拉杆式的光纤光栅应变传感器

提出了一种拉杆式的光纤光栅应变传感器,并进行了理论分析和传感器标定实验研究。传感器由悬臂梁组成弹性系统,将光纤粘贴于悬臂梁内锥形孔内,利用拉杆传递监测对象表面应变变化。实验结果表明,传感器的应变灵敏度为1pm/με,线性度为0.994;温度灵敏度为16pm/℃,线性度为0.996。可应用于高精度要求下的应变测量。     

边孔光纤光栅的传感特性

报道了一种新型边孔光纤及边孔光纤光栅的研究结果。采用有限元法分析了边孔光纤内部的应力分布和双折射数值,并通过波长扫描技术对其双折射进行了测量,理论计算和实验测量结果表明双折射数值达到4×10-5。根据边孔光纤光栅两反射峰偏振态相互正交的特性,提出了一种基于偏振检测的波长检测方案对边孔光纤光栅的传感特性进行了测量。结果表明两峰中心波长间隔随温度变化的灵敏度仅有0.05 pm/℃,是普通单模光纤光栅温度灵敏度的1/184。提出了一种基于横向荷载压力增敏的新型边孔光纤光栅封装装置,使边孔光纤光栅双峰间距的压力灵敏度从5.6 pm/MPa增加到119.14 pm/MPa,增敏21倍,实现了温度不敏感的高灵敏度压力传感。     

卫星环境温度监测的光纤光栅传感器研究

针对航天行业太空环境下对卫星内部温度监测的需求,研制了一种直接测量卫星内部温度的光纤光栅温度传感器。通过对传感器的结构进行了优化设计,选择一种新型的封装工艺,解决了温度、应变交叉敏感问题。选取相同封装条件的3个光纤光栅温度传感器进行温度标定。结果表明,在0～60 ℃范围内,光纤光栅温度传感器灵敏度分别为9.26 pm/ ℃、9.60 pm/ ℃、9.47 pm/ ℃,精度为1 pm,温度分辨率达到了0.1 ℃,线性度均达到0.998以上,具有良好的重复性与一致性,可应用于卫星内部温度的实时监测。     

光纤光栅温度传感器增敏封装特性研究

通过利用聚酰亚胺涂覆裸光纤光栅的方法研制了一种增敏型光纤光栅温度传感器,其反射波长的温度敏感系数由曾敏前的10pm/℃提升至40pm/℃。在-40~200℃测试环境中,开展了传感器标定和温度精度测量试验。试验结果表明:利用光纤光栅增敏封装,在高低温环境中采用低精度光纤光栅解调仪,传感器的测温精度由±0.4℃提升至±0.1℃。上述结果显示,采用增敏封装结构能够提升光纤光栅温度传感器的测量精度,减低制作成本。     

表面式温度补偿型光纤光栅传感器研究

设计了一种能用于恶劣环境下结构健康监测的具有温度补偿功能的新型光纤光栅应变传感器,该传感器利用参考光纤光栅原理实现温度补偿.依据传感器的结构,分析了表面式光纤光栅传感器的应变传递理论.根据应变传递理论给出了传感器结构参数,通过应变实验和温度实验,证明所设计的传感器的应变曲线和温度曲线的线性拟合度均在99%以上,光纤光栅的温度灵敏度为11.2 pm/℃,参考光纤光栅具有非常好的应变隔离性能,其温度灵敏度为4.3 pm/℃.     

全金属化应变不敏感FBG温度传感器特性研究

为了解决传统胶封光纤布拉格光栅(Fiber Bragg Grating,FBG)传感器存在严重胶蠕变和老化问题,提出基于一步超声波焊接的全金属化封装FBG传感器方法,采用有限元分析方法进行传感器的应变不敏感结构设计并制作了该温度传感器进行实验验证。测试结果表明,该方法制作的特定封装形式的FBG传感器对轴向应变不敏感,温度灵敏度达到39.16 pm/ ℃,是封装前裸光栅的4倍,线性度超过0.999,具有较好的重复性,并且温度从20 ℃改变到100 ℃的动态测量响应时间小于30 s。该金属化封装FBG温度传感器的工艺简单,制作周期短,其优异的温度传感特性在高精度、高可靠性传感监测领域具有广泛的应用前景。     

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.     

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.     

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.     

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.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.