More review problems for OM 13 What are differences between the common transmitted (or reflected)OM and polarized OM? 14. Can a polarized om be used to determine the orientation (or optical axis) of an anisotropic single crystal? State your reasonIng. 15. Can you see something from eyepiece lens when an isotropic crystal is on the sample stage of a polarized oM? Why or why not?
More review problems for OM 13. What are differences between the common transmitted (or reflected) OM and polarized OM? 14. Can a polarized OM be used to determine the orientation (or optical axis) of an anisotropic single crystal? State your reasoning. 15. Can you see something from eyepiece lens when an isotropic crystal is on the sample stage of a polarized OM? Why or why not?
Lecture-4 Scanning Electron Microscopy SEM) e What is SEM? Working principles of SEM Major components and their functions Electron beam -specimen interactions Interaction volume and escape volume Magnification resolution depth of field and image contrast Energy dispersive x-ray spectroscopy(EDS) Wavelength dispersive X-ray spectroscopy(Wds) Orientation Imaging Microscopy(OIM) X-ray fluorescence(Xre) http://www.mse.iastate.edu/microscopy http://www.youtube.com/watch?v=kynknr-e5iuto2:40inTroduction http://virtual.itg.uiucedu/training/em_tutoria http://science.howstuffworkscom/scanning-electron-microscope.htm/printable
Lecture-4 Scanning Electron Microscopy • What is SEM? • Working principles of SEM • Major components and their functions • Electron beam - specimen interactions • Interaction volume and escape volume • Magnification, resolution, depth of field and image contrast • Energy Dispersive X-ray Spectroscopy (EDS) • Wavelength Dispersive X-ray Spectroscopy (WDS) • Orientation Imaging Microscopy (OIM) • X-ray Fluorescence (XRF) http://www.mse.iastate.edu/microscopy http://www.youtube.com/watch?v=KYNknR-e5IU to 2:40 Introduction http://virtual.itg.uiuc.edu/training/EM_tutorial http://science.howstuffworks.com/scanning-electron-microscope.htm/printable (SEM)
Comparison of OM, TEM and sEM Probe "Source of Hight source e| ectrons一 -Condenser a magnetic lenses Specimen中 beam defacto objective Projector Specimen Eyepiece CRT Cathode Ray tube / IMAGE VIENED IMAGE ON detector DIRECTLY FL UORESCENT OM TEM SEM LIGHT MCROSCOPE Electronics ELECTRON MICROSCOPE ELECTRON MIC ROSCOPE Principal features of an optical microscope, a transmission electron microscope and a scanning electron microscope, drawn to emphasize the similarities of overall design https://www.youtube.com/watch?v=b4wosyktdn4comparingmicroscopesto0:12
Principal features of an optical microscope, a transmission electron microscope and a scanning electron microscope, drawn to emphasize the similarities of overall design. Comparison of OM,TEM and SEM OM TEM SEM Magnetic lenses detector CRT Cathode Ray Tube Light source Source of electrons Condenser Specimen Objective Eyepiece Projector Specimen https://www.youtube.com/watch?v=b4WOsYktdn4 comparing microscopes to 0:12 Probe
Optical Microscopy(OM)Vs Scanning Electron Microscopy (SEM) 25 radiolarian OM SEM Small depth of field Large depth of field Low resolution High resolution
Optical Microscopy (OM ) vs Scanning Electron Microscopy (SEM) 25mm OM SEM Small depth of field Low resolution Large depth of field High resolution radiolarian
What is SEM http://virtual.itguiucedu/training/em_tutorial Column SEM is designed for direct studying of of the surfaces of solid objects Sample ESEM Chamber □ XL30 ESEM-FEG Scanning electron microscope (SEM) is a microscope that uses electrons rather than light to form an image. There are many advantages to using the SEM instead of a OM https://www.youtube.com/watch?v=sfsfpxdaiam http://www.youtube.com/watch?v=irxmighanbgHowaSemworksw1:20-2:10 http://www.youtubecom/watch?v=saavaiLuobgOperationofSem
What is SEM Scanning electron microscope (SEM) is a microscope that uses electrons rather than light to form an image. There are many advantages to using the SEM instead of a OM. https://www.youtube.com/watch?v=sFSFpXdAiAM http://www.youtube.com/watch?v=lrXMIghANbg How a SEM works ~1:20-2:10 http://www.youtube.com/watch?v=SaaVaILUObg Operation of SEM Sample Chamber Column http://virtual.itg.uiuc.edu/training/EM_tutorial SEM is designed for direct studying of the surfaces of solid objects
Advantages of Using SEM over OM Magnification Depth of Field Resolution OM4x-1000X155m-019m 0.2um SEM10x-3000000X4mm-04um 1-10nm The sEM has a large depth of field, which allows a large amount of the sample to be in focus at one time and produces an image that is a good representation of the three-dimensional sample. The SEM also produces images of high resolution, which means that closely features can be examined at a high magnification The combination of higher magnification, larger depth of field, greater resolution and com positional and crystallographic information makes the SEM one of the most heavily used instruments in research areas and industries, especially in semiconductor industry
Advantages of Using SEM over OM Magnification Depth of Field Resolution OM 4x – 1000x 15.5mm – 0.19mm ~ 0.2mm SEM 10x – 3000000x 4mm – 0.4mm 1-10nm The SEM has a large depth of field, which allows a large amount of the sample to be in focus at one time and produces an image that is a good representation of the three-dimensional sample. The SEM also produces images of high resolution, which means that closely features can be examined at a high magnification. The combination of higher magnification, larger depth of field, greater resolution and compositional and crystallographic information makes the SEM one of the most heavily used instruments in research areas and industries, especially in semiconductor industry
Scanning Electron Microscope a Totally Different Imaging Concept e Instead of using the full-field image, a point- to-point measurement strategy is used e High energy electron beam is used to excite the specimen and the signals are collected and analyzed so that an image can be constructed e The signals carry topological, chemical and crystallographic information, respectively of the samples surface https://www.youtube.com/watch?v=vwxyszpttsiatw4:18-4:38 http://www.youtube.com/watch?v=irxmighanbgatn4:16-4:42 https://www.youtube.com/watch?v=npskvg]ktdi
Scanning Electron Microscope – a Totally Different Imaging Concept • Instead of using the full-field image, a pointto-point measurement strategy is used. • High energy electron beam is used to excite the specimen and the signals are collected and analyzed so that an image can be constructed. • The signals carry topological, chemical and crystallographic information, respectively, of the samples surface. http://www.youtube.com/watch?v=lrXMIghANbg at~4:16-4:42 https://www.youtube.com/watch?v=VWxYsZPtTsI at~4:18-4:38 https://www.youtube.com/watch?v=nPskvGJKtDI
Main Applications Topography The surface features of an object and its texture (hardness, reflectivity n. etc) Morphology The shape and size of the particles making up the object(strength defects in IC and chips.etc) Composition The elements and compounds that the object is composed of and the relative amounts of them (melting point, reactivity, hardnessmetc.) Crystallographic Information How the grains are arranged in the object (conductivity, electrical properties, strength.metc.)
Main Applications • Topography The surface features of an object and its texture (hardness, reflectivity… etc.) • Morphology The shape and size of the particles making up the object (strength, defects in IC and chips...etc.) • Composition The elements and compounds that the object is composed of and the relative amounts of them (melting point, reactivity, hardness...etc.) • Crystallographic Information How the grains are arranged in the object (conductivity, electrical properties, strength...etc.)
http://virtual.itguiucedu/training/em_tutorial A Look Inside the column Column Electron gun Gun alignment control Pneumatic air lock valve Condenser lens I+ Objective aperture canning coil Objective lens Motorized stag tage Sarnple Chamber http://www.youtube.com/watch?v=c7evtnvhn-satw1:10-2:10insidethecolumn
A Look Inside the Column Column http://www.youtube.com/watch?v=c7EVTnVHN-s at~1:10-2:10 inside the column http://virtual.itg.uiuc.edu/training/EM_tutorial
Amoredetailedlookinsidehttp://www.youtube.com/watch?v=sfsfpxdaIam Apeture I Microscope column 6V-100V5-50kV How Scanning Electron Microscopes Work Uc U c2009 How stutters <720 Electron Vacuum Anode ammar Figure 1 Gun Chamber tube e- beam Electron Gun Anode Conden Condenser Lens Electron CRT Condenser Beam Scan generator Lens robe-form 1平中 Objective BSE m Chamber Backscatter SE amplifier Detector Detector Specimen Seconda SC,EBIC Sample Detector Data Computer storage https://www.youtuBe.com/watch?v=mr9-1sz_cko Multichannel analyser at~1:06-2:40 Source: L. Reimer, " Scanning Electron https://www.youtubecom/watch?v=gy9if0-tvfe Microscope, 2nd Ed, Springer-Verlag at~2:38-4:45 1998,p.2 a- beam convergence
Source: L. Reimer, “Scanning Electron Microscope”, 2nd Ed., Springer-Verlag, 1998, p.2 e- beam Electron Gun https://www.youtube.com/watch?v=GY9lfO-tVfE at~2:38-4:45 A more detailed look inside - beam convergence <72o https://www.youtube.com/watch?v=Mr9-1Sz_CK0 at~1:06-2:40 http://www.youtube.com/watch?v=sFSFpXdAiAM
