ESPI solution for non-contacting MEMS-on-wafer testing

Rapid progress in the field of micro-electro-mechanical systems (MEMS) makes the development of appropriate measuring and testing means timely. Characterizing the mechanical properties of MEMS structures at a very early stage of manufacturing is a challenging task for quality assurance in this field. The paper describes a new solution that is based upon the vibration analysis of the microparts. The nanometer amplitudes are detected by advanced electronic speckle pattern interferometry (ESPI). A specific signal processing technique has been applied to make the solution robust. Comprehensive numerical simulations provide the theoretical base for the HNDT concept. A laboratory system for 4″ wafer has been built, and extensive tests show that such key properties as e.g. the thickness of springs or membranes can be determined exactly. Automated frequency scanning and corresponding digital image processing open the way to reliable and fast industrial systems for MEMS testing on wafer level.     

Analysis of the Electronic Vibrational Spectra of Bisanthene by Calculating Normal Modes

At 4.2 K, the quasiline fluorescence and fluorescence-excitation spectra (in the region of the S ₁ S ₀- and S ₂ S ₀ transitions) of bisanthene in n-hexane have been obtained. Using the MO/M8ST method, the calculation of the A _g normal modes in the S ₀, S ₁, and S ₂ electronic states was carried out for the bisanthene molecule; the relative intensities of the transitions in the corresponding vibronic spectra were also calculated. The analysis of the results of calculations and experiment made it possible to draw conclusions on the form of the modes for a number of normal vibrations which are active in the bisanthene vibronic spectra.     

导体旋转椭球电学量的一种计算方法

用一种新方法，计算了孤立导体旋转椭球的面电荷密度、电容、电势和电场强度，并得出相应的解析表达式。     

高能量激光诱导铝等离子体的发射光谱研究

用钕玻璃激光器 (～ 2 5J)烧蚀铝靶获得等离子体 ,以氩气作为保护气体 ,分析了环境气压、等离子体的观测高度、工作电压、激光功率密度对谱线强度的影响 ,并进行了简短的讨论。实验结果表明 ,环境气压为 88kPa时谱线强度最大 ;相同气压下随着观测高度的增大 ,谱线强度明显减弱 ,在气压为 88kPa观测位置距样品表面 1 5～ 2mm时谱线强度较强 ;并且随着激光工作电压、功率密度的增大 ,谱线强度逐渐提高。     

一种新型非晶态分子材料的非线性光学折射率和吸收特性

用单光束扫描法测量了在532nm处一种新型非晶态分子材料5,5′Bis(dimesitylboryl)2,2′bithiophene的非线性折射率和吸收系数样品非线性透射特性的分析表明,在靠近线性吸收区的532nm处有饱和吸收存在由三能级饱和模型和Zscan法确定了饱和强度、非线性折射率的实部和虚部研究结果表明:这种新型非晶态分子材料具有非常好的光子学应用前景.     

Eu3+掺杂铌酸盐玻璃的光谱性质

研究了Eu^3 掺杂铌磷与铌硅系列玻璃的发射光谱，声子边带谱及^5D0能级寿命，计算了样品的强度参数。随着Nb2O5浓度的增加，Eu-O键强增大，共价性增强，Eu^3 的局域环境对称性降低，电－声子耦合增强，^5D0能级的无辐射过程加快，寿命变短，温度猝灭加剧。研究了从77－690K铌磷与铌硅系列玻璃中Eu^3 离子在488nm激光激发下的变温荧光发射特性，求出了温度猝灭速率。分析了发光强度增强与减弱的原因，即热布居与无辐射过程随温度的变化关系，研究了谱线宽度与峰值位置随温度的变化关系。     

NO分子A2Σ→X2Π双光子激光感生荧光光谱

以Nd∶YAG激光器抽运光学参变振荡器 /光学参变放大器做为激发源 ,得到了NO分子在 2 2 0～ 35 0nm波长范围内的双光子激光诱导荧光光谱 ,并将其归属于A2 Σ(ν′ =0 )→X2 Π(ν″ =1～ 8)跃迁 ,用最小二乘法拟合获得NO分子X2 Π态振动常量″ωe =(190 4 .7± 7.3)cm-1,″ωe ″xe =(14 .2± 1.2 )cm-1,″ωe″ye=- (0 .0 2 18± 0 .0 0 91)cm-1,及平衡位置的力常量k =(1.5 99± 0 .0 12 )× 10 3 N·m-1。计算了所得跃迁谱带的弗兰克康登因子及相对荧光强度 ,结果与实验观测值相符。这可为用激光诱导荧光光谱技术探测大气污染物NO分子提供理论及实验参考     

基于电吸收调制器的解复用器窗口特性分析及优化

数值模拟了基于电吸收调制器 (Electro absorptionmodulator,EAM)解复用器的开关窗口特性 ,在考虑邻道串扰和强度抖动 (由同步偏离和时间抖动导致 )的光时分复用数值模型中对解复用信号的误码率进行分析。数值模拟结果表明 ,电吸收调制器的窗口特性 (消光比和窗口宽度 )满足 4× 10Gb/s的光时分复用通信系统中解复用器的要求 ;在小的偏置电压下 ,邻道串扰和解复用器的透过率特性必须仔细考虑以达到最小的误码率 ;在大的偏置电压下 ,较大的射频幅度将会使解复用信号误码率最小     

基于半波带分析法的菲涅耳波带片衍射特性的讨论

基于半波带的分析方法简单明了地分析了平行光经菲涅耳波带片衍射后的多焦点特性以及各焦点的光强变化规律．     

一种软X射线多层膜界面粗糙度的计算方法

提出一个利用多层膜小角X射线衍射谱衍射峰积分强度计算多层膜界面粗糙度的公式。用磁控溅射技术制备Mo／Si多层膜，用波长为0．154nm的硬X射线测量样品在小掠入射角区的衍射曲线，分别用本文公式和反射率曲线拟合方法计算了样品的界面粗糙度。实验结果表明：由本文公式获得的界面粗糙度近似于拟合方法获得的界面粗糙度，它们略等于多层膜界面实际粗糙度。