基于Zn2SiO4：Mn的紫外探测薄膜的研制

由于紫外光对硅层的透射深度小于2nm,所以传统的光电探测器件并不响应紫外光。为了增强传统的光电探测器件在紫外波段的探测能力,实用的方法是在传感器光敏面镀上“紫外一可见”变频薄膜,将紫外光转化为可见光。实验用“旋涂法”在石英基底上生成ZnzSiO4：Mn紫外探测薄膜,并对其透射光谱、吸收光谱、激发光谱与发射光谱等光学性质进行测量分析。实验测得薄膜在300nm以下透过率极低,在300nhm以上透过率很高且平稳;对300nm以下的光具有很强的吸收,对300nm以上的光吸收很弱且很平稳;激发峰在265nm,发射峰在525nm,即能将紫外光转化为可见光。实验结果表明薄膜不仅能将紫外光转化为可见光,实现传统光电探测器件的紫外探测。而且在增强紫外响应的同时不削减其他波段的响应,是一种适用于增强光电图像传感器紫外响应的紫外增强薄膜。     

表面钝化膜对BCMOS传感器电子敏感特性影响的实验研究

基于硅表面的薄膜钝化原理,开展了不同厚度的表面钝化膜对背减薄CMOS(Back-thinned CMOS,BCMOS)传感器电子敏感特性影响的实验研究。首先,对CMOS传感器进行背减薄处理后,对背减薄CMOS进行电子轰击测试,由测试结果可知,电子图像灰度随入射电子能量的变化呈现出线性关系。然后,采用电子束蒸镀法在BCMOS传感器表面镀制了不同厚度的氧化铝薄膜,并进行了电子轰击测试。研究发现,当表面氧化铝薄膜厚度为20 nm时,可以将BCMOS传感器的二次电子收集效率提高14.9%,通过表面薄膜钝化实现了电子敏感性的提升,同时,随着薄膜厚度的增加,BCMOS暗电流由1510 e-/s/pix减小至678 e-/s/pix。上述结果说明,氧化铝薄膜对BCMOS背减薄表面具有良好的钝化作用,可以提高BCMOS传感器的二次电子收集效率、降低暗电流,为将来高灵敏度EBCMOS器件的研制提供了技术支撑。     

激光对CCD及CMOS图像传感器的损伤阈值研究

针对激光对CCD及CMOS图像传感器的干扰损伤进行了理论分析和实验研究.实验测量出常压及真空条件下1064nm激光对CCD及CMOS图像传感器的干扰阈值、损伤阈值及完全损坏阈值.实验结果表明,CCD或CMOS图像传感器的各种阈值在常压和真空两种不同条件下的差别不明显.实验结果还显示,无论在常压还是在真空条件下,CCD比CMOS更容易受到激光的干扰和损伤甚至严重损坏;而CMOS相机具有很好的抗干扰和抗损伤能力.     

无滤光片的红外像元结构

用基于CCD或CMOS的图像传感器制作的成像系统一般都需要在光学系统中使用红外滤光片。这是因为基于半导体的普通图像传感器件不仅能响应可见光,而且还能响应780nm～1100nm范围内的红外光。如果不使用红外滤光片,它们就不可能获得高质量的彩色图像,因为这会造成图像失真。单色成像器还需要用红外滤光片来正确维持景物发光。     

Al掺杂ZnO紫外探测器的快速响应技术

通过交变电场下的紫外光响应测试,观察到ZnO基薄膜在254 nm紫外光激发下的慢响应现象,并测量了响应时间常数。为提高ZnO基薄膜紫外探测器的性能,采用磁控溅射法,制备了纯ZnO薄膜和掺Al浓度为10 at.%(原子比例)的ZnO薄膜紫外探测器,测量了样品的频率特性曲线。结果表明,Al掺杂能有效地抑制ZnO薄膜的慢响应,实现探测器对紫外光的响应时间常数τ<25μs的快速响应。     

超连续谱光源辐照可见光CMOS图像传感器的实验研究

研究了超连续谱光源对可见光CMOS图像传感器辐照的实验现象和规律。观察到随着入射激光功率的不断增大，CMOS图像传感器依次出现了像元饱和、局部饱和、局部过饱和以及全屏饱和等现象。与1 060 nm锁模光纤激光辐照同种图像传感器的实验相对比，从有效干扰面积、图像相关度及图像均方差等三个方面，对比了两种干扰源在影响CMOS图像传感器成像质量方面的异同，发现CMOS图像传感器的响应特性、激光的频谱特性和成像光学系统的色散是导致干扰效果差异的主要原因。     

紫外增强图像传感器的研究进展

近年来图像传感器在紫外成像的应用越来越广泛,尤其是以CCD（charge coupled device）和CMOS（complementary metal oxide semiconductor）为主的紫外图像传感器受到了研究人员的广泛关注。半导体技术的进步和纳米材料的发展进一步推动了紫外图像传感器的研究。本文综述了国内外紫外增强图像传感器的研究进展,介绍了几种增强器件紫外响应的材料,另外还简要概述了紫外图像传感器在生化分析、大气监测、天文探测等方面的应用,并讨论了CCD/CMOS图像传感器在紫外探测方面所面临的挑战。     

酞菁铜蒸发镀膜工艺中膜厚控制参数的确定

基于目前采用的膜厚仪中缺少必要的有机材料的参数(密度和声阻抗),采用真空蒸镀法,在抛光硅片上蒸镀不同显示值厚度下的酞菁铜薄膜,利用椭偏仪测量其真实膜厚,并使用数学软件MATLAB,结合膜厚仪实时监控原理进行理论计算,拟合得到酞菁铜薄膜的参数——声阻抗Zf=0.01 g/cm3.s,薄膜密度Df=6.68 g/cm3。验证实验结果表明,此参数输入膜厚仪中可以比较精确地控制薄膜厚度,显示值和实际测量值的差距约为3 nm。     

基于银纳米薄膜欧姆接触的高波长选择性紫外探测器研究

常规的半导体紫外探测器波长响应范围宽,而紫外光的应用具有较强的波长选择性,如320nm波段的紫外光在医学方面有重要的应用,因此,具有高波长选择性的紫外探测器的研制有重要意义。文章采用GaN基p-i-n探测器结构,通过在p区覆盖银纳米薄膜作为欧姆接触层和波长选择透射层,成功制备了对320nm波段紫外光高选择性探测的紫外探测器,器件性能如下:70nm银层的紫外光透射率峰值超过30%,器件在-5V偏压下的暗电流为10-12 A量级,响应峰值为0.06A/W,响应峰发生在325nm处,光谱响应峰半高宽约30nm。     

ZnO薄膜紫外探测器的光电性质

采用直流反应磁控溅射的方法制备ZnO薄膜, 用X射线衍射仪(XRD)、扫描电镜(SEM)和紫外-可见光谱仪(UV-Vis)分别表征ZnO薄膜的晶体结构和表面形貌等特征。并用此材料制备Au/ZnO/Au金属-半导体-金属(MSM)结构光电导型ZnO薄膜紫外光探测器。实验结果表明, ZnO探测器在360 nm出现明显光响应,其光电流为2.5 mA, 在5 V偏置电压下暗电流为250 μA; ZnO紫外探测器在250～380 nm的紫外波段, 探测器有很明显的光响应, 且光电流响应比较平坦; 在380～430 nm区域, 光响应明显下降; 其光响应的上升与下降弛豫时间分别为20 s与80 s。从光谱响应图中可以看出紫外(360 nm)比可见区(450 nm)的光响应高出3个数量级, 薄膜表面存在的缺陷(如氧空位)在ZnO紫外探测器的光电效应中有重要作用。     

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.