TEM主要英语词汇.doc

第二篇 金属电子显微分析Electron Microanalysis for Metals 第一章 电子光学基础The Electron Optics引言1.显微分析的任务：了解材料的化学成分、形貌和晶体结构The microanalysis: Composition, topography, and crystals construction.2.电子光学仪器：透射电子显微镜（TEM）,扫描电子显微镜(SEM) The instrument of electron optics: Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM)3.以电子光学方法将具有一定能量的电子(或离子)会聚成细小的入射束，通过与样品物质的相互作用激发表征材料微观组织结构特征的各种信息，检测并处理这些信息从而给出形貌、成分和结构的丰富资料，是所有电子光学仪器的共同特点。3.The incident beam of electrons (or ions) condensed with electronic optics technique interact with the materials of samples to exact and product the information of materials topography, crystals construction, and also, to detect and to treat these information about the composition, topography, and crystals construction.4.微区分析新技术4.Micro-analysis technique.1.1.几何光学: 折射定律，Geometric Optics :Refractive law光的折射是其成像基础。Refraction Law, the basic principle of imaging. 薄透镜性质Thin lens properties： 1）薄透镜焦距定律Thin lens focus law：(1/L1)+ (1/L2)=1/f,L1 薄透镜物距 Object distance ； L 2薄透镜像距 image distance；f薄透镜焦距focus。 放大倍数Magnification :M = L2/L11.2.光学显微镜以及它得分辨率极限受到可见光波长的限制Optical Diffraction, Optical microscope and limitation of its ResolutionVisible light： wavelength: 390nm760nm根据衍射理论推导，点光源通过透镜产生的埃利斑半径 Radii of Airy spot ：Ro =( 0.61 /n sin)M,式中 n- 透镜物方介质折射率Refractor in object side；-照明光波长Wavelength； -透镜孔径半角 Half angle of aperture of lens；M-透镜放大倍数Magnification of lens.说明：埃利斑半径与照明光源波长成正比，与透镜数值孔径成反比。两埃利斑中心间距等于第一暗环半径R0。此时样品上相应的两个物点间距离r0。定义为透镜能分辨的最小距离，也就是透镜的分辨本领： ro =( 0.61 /n sin)对于玻璃来说，最大的孔径半角=7075，物方介质为油情况下，n 1.5，其数值孔径 nsin 1.25 1.35。因此式可以简化为：ro =(1/2) 以上说明分辨本领主要取决于照明波长。可见光的波长在39007600之间，光学透镜分辨本领极限值可达2000。由衍射,埃利园斑决定.Diffraction, the Airy spot size: RO=(0.61/n sin )MResolution for visible light ro=(1/2)1.3.有效放大倍数 Effective Magnification for microscope The resolution of persons eyes is 0.2mm, but the resolution of Optical microscope is 0.2m （2000）.The effective magnification is Meff =re/r0HerereThe resolution of persons eyes, r0the resolution of Optical microscope 人眼的分辨本领大约是0.2mm，光学显微镜分辨本领极限大约是0.2m（2000）有效放大倍数: M =re/r0式中M有效显微镜有效放大倍数；re人眼分辨本领；r0显微镜分辨本领。 The effective Magnification of Optical microscope Meff=1000, The largest magnitude is 10001500. If we want to increase Meff the most important thing is to use the source with short wavelength.光学显微镜相应的有效放大倍数M有效=1000倍，最高放大倍数在10001500倍。若要提高显微镜的分辨本领，关键是要有短波长的照明源。光学显微镜与电子显微镜的比较Comparing table for optical microscope and electronic microscope (TEM)表1.光学显微镜与电子显微镜的比较表Table 1.Comparing table for optical microscope and TEM光学显微镜Optical microscope电子显微镜Electronic microscope (TEM)照明束Illumination beam可见光 Visible light电子束 Electron beam波长Wavelength390nm760nm=(150/U)1/2 e.g. U =100kv, =0.0037nm透镜的分辨率Resolution由衍射,埃利园斑决定diffraction, the Airy spot sizeRO=(0.61/n sin )M分辨Resolutionro=0.61/(n sin )ro=(1/2)1、 衍射, 埃利园斑diffraction, the Airy spot size RO=(0.61/n sin )M 2、 球差Spherical aberration CS分辨Resolution ro=0.49CS1/43/4最好分辨The best resolution200nm0.1nm （300kv）放大倍数Magnification10001500几十万倍 600K透镜Lens光学透镜Optical Lenses电磁透镜Electric and Magnetic Lenses条件Condition大气Atmosphere真空Vacuum1.4. 电子的波性及其波长 Wavelength of electron wave 1. 电子波粒二相性，Duplication of the electron wave2. 德布罗义关系式 Formula of de Broglia wave P=h/, 式中 hPlank const,普朗克常数, is the wavelength, 波长。 这个波叫做物质波或德布罗意波。粒子的运动服从波粒二象性的规律。一个初速为0的电子，受加速电压U的作用获得的运动速度为，它们之间的关系为： (1/2)mv2=eU, 整理得： = h / (2meU)1/2 把h=6.6210-34Js，e=1.6010-19C，m0=9.1110-34kg 代入（1-12a）可得： Formula of de Broglia wave Electronic wavelength:电子波长 Wavelength of electron wave ：； U:V第二章 透射电子显微镜 Transmission Electron Microscope (TEM)2.1透射电子显微镜构成： Construction of TEM: 1、电子光学系统（镜筒）；Electron Optics system1)电子光学系统Electron Optics system :电子枪 Electron gun, 聚光镜 Condenser, 倾斜调节装置 Tilt assembly2)成象系统Imaging System：物镜 Object Lens， 中间镜 Middle Lens (Intermediate lens) ， 投影镜 Project Lens；3)图象记录系统Record System of image；4)样品架Specimen holder， 样品铜网 Cupper grid2、电源和控制系统（包括电子枪高压电源，透镜电源，控制线路电源等）Power supply and control system (include High voltage power supply for electron gun, power supply for lenses, and power supply of control circuits) 包括电子枪高压电源 High Voltage Power Supply, 透镜电源 Power Supply for lenses ，控制线路电源 Power Supply for Circuits of control3、真空系统Vacuum System机械泵Mechanical Pump，扩散泵 Diffusion pump2.2照明系统System of illumination of electron 透射电子显微镜照明系统由电子枪、聚光镜、和相应的平移对中，倾斜调节装置组成。The system consists of Electron gun, Condenser and tilt assembly.1.电子枪Electron gun, 常用的是热阴极三极电子枪，由发夹形钨丝阴极hear type W cathode 栅极帽 Wenelt 和阳极 Anode 组成。Electron gun comprises of heat cathode of 3 electrodes， hear type W cathode ，Wenelt and Anode.阳极接地 Anode connected ground，阴极接负高压 Cathode connected minus high voltage 。阴极电子发射率i0主要取决于阴极工作温度（一般在25002700K左右）：2.3成象系统：Imaging System：1.物镜、中间镜和投影镜 物镜是最关键的，决定显微镜分辨本领的高低。通常采用强激磁、短焦距的物镜，像差小。还借助于物镜光阑和消像散器来进一步降低球差、消除像散、提高分辨本领。Object lens is the key lens depended on the resolution. Short focus, the aberration small.中间镜是一个弱激磁的长焦距变倍透镜，可在020倍范围调节。Middle lens (Intermediate lens) has long focus, the magnification could be 0-20.为确保成像系统足够高的放大倍数，投影镜提供尽可能大的放大倍数。它是一个强激磁、短焦距透镜。Project lens has enough high magnification, which is a short focus lens.2.透射电镜的三种工作模式3 Models of TEM：1)三级高放大倍数成像：三级透镜成像系统可以获得高达二十万倍左右的电子像。High magnification model of imaging with 3 classes of lenses. 2)三级中放大倍数成像：使物镜成像于中间镜之下，中间镜以物镜像为“虚像”，将其形成为缩小的实像于投影镜之上；投影镜以中间镜像为物，成像于荧光屏或照相底片上。结果获得极几千至几万倍的电子像。Middle magnification model of imaging (several thousands to several tens of thousands) with 3 classes of lenses. 3)二级低放大倍数成像：关闭物镜，减弱中间镜激磁强度，是中间镜起着长焦距物镜的作用，获得100300倍图像。Low magnification model of imaging is with 2 classes of lenses. H-800透射电子显微镜H-800 type TEM:主要指标： Specification:加速电压 Accelerate voltage：200KV点分辨 Point resolution： 4.5埃晶格分辨 Lattice resolution ：2.04埃放大率Amplitude：600000 最大60万倍第三章 样品制备3.1. 质厚衬度原理 Principle of mass and thickness contrast3.2. 4种基本的复型技术4 kinds of Replica：1)塑料一级复型 Plastic Single-Stage Replica2) 碳一级复型 Carbon Single-Stage Replica3) 塑料一碳二级复型Two-Stage Replica(Technovit, Triafol)4)抽取复型Extraction Replica. 3.3. 薄膜样品的制备方法 The method of Thin film samples步骤Steps:预减薄:机械减薄，化学减薄Pre-thinning Mechanical-thinning, chemical thinning,最终减薄,双喷减薄器The final thinning: Jet-polishing technique3.4. 近年来薄膜样品的制备的新技术New technique for Fabrication of samples for TEM ：离子减薄仪等 Ion bombardment thinning instrument第四章 电子衍射Electron diffraction4.1.概述Introduction 多晶体的电子衍射花样:一系列不同半径的同心圆环，而单晶花样由排列的十分整齐的许多斑点所组成。The pattern of poly-crystals likes rings.4.2.布喇格定律Bragg Law 晶体对电子波的衍射现象，与X射线衍射一样，采用不喇格定律加以描述。当波长为的单色平面电子波以掠射角照射到晶面间距dhkl的平行晶面组（hkl）时，若满足：2dsin = n , n=1，1，2，3， ，叫做衍射级数diffraction class.干涉面指数：H K L 2dsin= As in the case of X-ray diffraction, the patterns are formed by diffraction of the electron beam (typically 50-200kev) transmitted through the thin sample. 4.3.倒易点阵和爱瓦尔德球作图法 Reciprocal lattice and Ewald spherical1. 倒易点阵定义Definition of Reciprocal lattice The Reciprocal lattice have the basic unit vectors a*, b*, and c*, that And here, Vc is the unit cell volume of the real lattice. 2. 倒易矢量reciprocal vector： The reciprocal lattice unit cell defined by a*、b* and c* : ghkl is the reciprocal lattice vector ghkl = ha*+kb*+lc*在立方点阵的倒易点阵中，任意倒易矢量ghkl平行于相应晶面指数相同的晶面（h k l）的法线方向。The reciprocal lattice vector ghkl is normal to the crystal plane (hkl), and its length equal to 1/d hkl .有关词汇：电子衍射 Electron Diffraction,倒易矢量reciprocal lattice vector ,倒易点阵 reciprocal lattice, 布拉格方程 Bragg equation ,厄瓦尔德球 Ewald sphere (radii is 1/) in reciprocal space, 结构因子 Factor of structure 重金属投影 Project of heavy metals复型技术 Replica techniques4种基本的复型技术4 basic replica techniques：1)塑料一级复型制备方法Single stage plastic replica：2)碳一级复型 Single stage carbon replica ；3)塑料-碳二级复型 2 stage plastic- carbon replica；4)抽取复型 Extraction replica；4.4电子衍射基本公式和相机常数 Basic Formula of Electron Diffraction and Constant of camera 电子衍射基本公式Basic Formula of Electron Diffraction：Rd=L电子衍射基本公式矢量表达式Basic Formula of Electron Diffraction of vectors：R =(L)g = K g, 相机常数Constant of camera K=LDiffraction fomula k-k=g选区成像 Selected area pattern选区衍射Selected area Diffraction衬度Contract, 电子衍射衬度 Electron diffraction contract明场 light field暗场 dark field第六章 扫描电镜Scanning Electron Microscope(SEM)6.1. 扫描电镜的原理和构成The Principle of Scanning Electron Microscope1.扫描电镜的原理类似于闭路电视。SEM is like the Close-