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48 

 

J. M. Allaz © March 14, 2021

 

 

 

Figure 27.

 Processing and extracting element maps. 

 

 

 

Содержание JSM-6390 LA

Страница 1: ...Scanning Electron Microscope SEM JEOL JSM 6390 LA User s manual Julien M Allaz March 14 2021 Version 1 4...

Страница 2: ......

Страница 3: ...3 D 2 Vertical displacement Z 13 D 3 Rotation R 13 D 4 Tilting T 13 E Activate the electron beam 15 E 1 Activating a LaB6 electron source in LaB6 mode 15 E 2 Activating a W electron source in LaB6 mod...

Страница 4: ...Spectrum 43 J 5 3 Exporting a Point Shoot analysis 43 K EDS element mapping 45 K 1 Acquiring an element map with the mode Spectral Imaging 45 K 2 Treating element or phase maps 47 K 2 1 Extracting El...

Страница 5: ...D ERDW IGP has SE secondary electron BSE backscattered electron and CL cathodoluminescence imaging capabilities and can provide accurate standard based quantitative analyses of major and some minor e...

Страница 6: ...1 Turn ON both computer screens 2 Check the general status of the instrument o Is it working and under high vacuum Check the vacuum controller box on wheel on the LEFT side of the instrument with ind...

Страница 7: ...ended Thermo NSS Section H is used for acquiring and saving high quality images The middle right side controls either the brightness and contrast when STIG is OFF or the astigmatism correction when ST...

Страница 8: ...ction electron image display with grey buttons used to control the image quality and on the right side a snapshot image of the sample holder Bottom section instrument status voltage WD spot size etc F...

Страница 9: ...SEM manual ETHZ v1 4 5 Figure 5 Overview of the main buttons in the TOP section of the SEM program...

Страница 10: ...6 J M Allaz March 14 2021 Figure 6 Overview of the MIDDLE section of the SEM program Figure 7 Overview of the BOTTOM section of the SEM program...

Страница 11: ...user and see if you can wait for the completion or if you can cancel the analysis 4 Turn ON the infrared camera Deben small screen on the left Fig 8 Figure 8 Main SEM detectors and components visible...

Страница 12: ...8 J M Allaz March 14 2021 Figure 9 Preparing the sample holder for thin section or for 1 round mount...

Страница 13: ...NOT apply if the SEM is in W mode see Appendix A2 8 When fully vented open the sample chamber see C 2 and Figure 11 C 2 Removing Loading a sample closing the chamber 1 Open the sample chamber up to th...

Страница 14: ...10 J M Allaz March 14 2021 Figure 10 Opening the sample chamber to remove or place a sample...

Страница 15: ...SEM manual ETHZ v1 4 11 Figure 11a Loading a new sample and taking an overview image of your sample SNS...

Страница 16: ...12 J M Allaz March 14 2021 Figure 11b Evacuating pumping the sample chamber after un loading a sample...

Страница 17: ...to ensure that the stage does not bump into the BSE or the CL detector Repairs can be costly To move the sample up or down along the Z axis Open the window Stage and two options Safest Use the cross s...

Страница 18: ...14 J M Allaz March 14 2021 Page left blank intentionally a good place for your notes J...

Страница 19: ...usually left in standby condition the filament heat is just enough to keep the filament warm but not enough to emit electron You ll need to perform a filament saturation by setting the filament heat...

Страница 20: ...March 14 2021 Figure 12 Activation of the electron beam in LaB6 mode Two different processes depending on the electron source currently used LaB6 cathode or W filament Refer to Appendix A2 if the SEM...

Страница 21: ...e of the TILT until the beam current is maximised repeat for the Y value of the TILT 5 Increase the current Spotsize 90 and adjust the SHIFT X Y values 6 Set back a low beam current e g spotsize 50 or...

Страница 22: ...al part of the sample holder increase the magnification to 100 or 200x so you don t see the edge of the CL detector anymore 6 Locate a small particle or some marks intersecting at 90 7 Adjust the brig...

Страница 23: ...SEM manual ETHZ v1 4 19 Figure 13 Complete procedure for beam alignment...

Страница 24: ...2021 Figure 14 Detail on the adjustment of the Z stage position for quantitative analysis and SE BSE imaging optimum Z 10 to 11 mm at a fixed Working Distance WD 10 mm versus cathodoluminescence imag...

Страница 25: ...SEM manual ETHZ v1 4 21 Figure 15 Detail on the beam alignment procedure to obtain the best image quality...

Страница 26: ...ation of brightness contrast Constantly adjust B C to reveal what you need to see Avoid under black or over saturated white areas unless a high contrast is required to reveal a small signal variation...

Страница 27: ...tector G 1 Inserting or removing the CL detector WARNING Whenever you insert or remove the CL detector ensure that the Z stage position is at 30 mm Figure 17a Inserting or removing the CL detector WAR...

Страница 28: ...Sections H To acquire a single or mosaic image follow the instructions given in Sections I WARNING If the OVERLOAD button turns ON Fig 17b it means that the detector is saturated with light Either you...

Страница 29: ...ommended to create a NEW project folder per analytical session1 o Select your user data folder E LastName FirstName If a folder with your last name and first name does not exist In Project Explorer se...

Страница 30: ...26 J M Allaz March 14 2021 Figure 18 Creating a new NSS project or opening an existing one...

Страница 31: ...gram NSS consists of several panels described in Figure 19 The present manual only covers the essential functionalities of the modes Electron Imaging Spectrum Point Shoot or Spectral Imaging hyperspec...

Страница 32: ...28 J M Allaz March 14 2021 Page left blank intentionally a good place for your notes J...

Страница 33: ...ication to the desired field of view Avoid low magnification 100x as you will have edge effects shadow deformation Adjust the Z stage position for SE BSE images at fixed WD or the focus for CL images...

Страница 34: ...30 J M Allaz March 14 2021 Figure 20 Electron Imaging mode acquire a single image in Thermo NSS...

Страница 35: ...under the Stage Movement b Click on the button to add a new grid It opens a frame with options i Enter a name for this grid The final name of each image of the mosaic will be Base Name Grid Name 0 0...

Страница 36: ...32 J M Allaz March 14 2021 Figure 21 Electron Imaging mode acquire a mosaic image in Thermo NSS...

Страница 37: ...al image i e consider the true pixel size in micrometre Check the Appendix A4 for determining the pixel size of your individual image of the mosaic Do not choose a too high magnification that would re...

Страница 38: ...34 J M Allaz March 14 2021 Page left blank intentionally a good place for your notes J...

Страница 39: ...WD 9 700 at 15 keV or 9 800 at 20 keV Figure 22 SEM EDS information found at the footnote of the NSS program acceleration voltage ACC magnification MAG working distance WD last beam current measuremen...

Страница 40: ...red at the same VOLTAGE as your analyses usually 15 kV If multiple standards are available such as Fe2O3 and FeS2 for Fe at the same kV choose the one the most similar to the type of phase to be analy...

Страница 41: ...SEM manual ETHZ v1 4 37 Figure 23 Loading standards into your project for quantitative EDS analysis...

Страница 42: ...ure the last checkbox Measure beam current is checked f Click OK 3 Move the stage in position for the analysis fine tune the Z stage position and increase the magnification usually 1000x to scan only...

Страница 43: ...SEM manual ETHZ v1 4 39 Figure 24 Spectrum Acquiring a single EDS spectrum over the currently scanned area...

Страница 44: ...ctangle an area with similar intensity a circle or a polygon Use a single click for point click and drag for rectangle and circle and left click for each corner of a polygon right click to close the p...

Страница 45: ...SEM manual ETHZ v1 4 41 Figure 25 Point Shoot Acquiring multiple EDS analyses selected on an electron image...

Страница 46: ...efault it assumes that each element is an oxide and it will force the recalculation of oxygen by stoichiometry If you analyse sulphide metal or other non oxide you should deactivate this checkbox J 4...

Страница 47: ...ight Number of Cations Atomic proportion from the oxygen normalisation Standard Name Name of the standard file used can be useful for your record On the top right part of the Properties window you can...

Страница 48: ...44 J M Allaz March 14 2021 Page left blank intentionally a good place for your notes J...

Страница 49: ...aging EDS and Spectral Imaging a Tab Imaging The spectral imaging needs a base BSE or SE image Set the resolution for this BSE image e g 1024x768 pixels 2 frames 10 s each b Tab EDS You only need to s...

Страница 50: ...you can add or remove identified elements using the periodic table in the tab Element Setup on the bottom left panel and request to reprocess the data to extract more elements see more in Section K 2...

Страница 51: ...tional options once the maps are extracted K 2 2 Extracting Phase maps To extract phase maps see Fig 28 1 Activate first the COMPASS mode and choose either a Components to show the principal component...

Страница 52: ...48 J M Allaz March 14 2021 Figure 27 Processing and extracting element maps...

Страница 53: ...SEM manual ETHZ v1 4 49 Figure 28 Calculating and extracting phase maps...

Страница 54: ...that this option will likely include pixels from other phases surrounding the phase of interest Double click on the name of a phase to rename it once you have properly identified it Use the spectrum e...

Страница 55: ...ired if the sample is not centred yellow line NOT in the middle of the stage holder To perform the adjustment see also Fig A1 o Press the button Adjust Ensure the Holder Size 32 mm is selected o Adjus...

Страница 56: ...with SNS as usual Then lower the stage to 30 mm Close the sample chamber keep an eye on the IR camera Press the button EVAC to pump Wait for the signal READY The HT button should now be blue Press on...

Страница 57: ...SEM manual ETHZ v1 4 53 Figure A2 Saturation of the W filament in W mode When the optimum is reached the emission current should read 30 to 50 A or higher...

Страница 58: ...eristic X ray Figure A3 All common electron transitions and characteristic X ray generation From Goldstein et al 2003 Scanning Electron Microscopy and X Ray Microanalysis Fig 6 9 p 280 Original in Wol...

Страница 59: ...2 x 40 sec instead of the regular 2 x 10 sec For EDS element mapping consider smaller images e g 256 x 192 px and select an image resolution and magnification such that the pixel size is equal or lar...

Страница 60: ...in plagioclase In this case you should certainly first discuss with the lab manager Use Figures A5 1 and A5 2 as a reference to define the minimum counting time per frame to reach the desired quality...

Страница 61: ...SEM manual ETHZ v1 4 57 Figure A5 2 Relationships between magnification map pixel size and counting time Use these plots to estimate the best analytical conditions for your needs...

Страница 62: ...58 J M Allaz March 14 2021 A6 Thermo NSS toolbars from the NSS manual...

Страница 63: ...ral image SI binary file Compressed binary data of the spectral image SIREF TIF file Raw BSE or SE image at the full resolution without scale bar A7 4 Export files generated by Thermo TIF TIF file Exp...

Страница 64: ...scale phase maps Morphology operation to account for overlapping excitation volumes User adjustable image output Ratio of two compounds in a single phase e g Ca Na in plagioclase And more Figure A8 Ex...

Страница 65: ...repolish it to remove the coating and re coat it with 20 nm carbon Ask for assistance if necessary Are you analysing beam sensitive material e g hydrated phase Na or K rich phase carbonate phosphate...

Страница 66: ...e itself Try again It should now work In imaging mode SE BSE CL you might sometime see a shadow on one corner or on one edge of the image This is most likely due to a very bad alignment of the beam ap...

Страница 67: ...orm the reset of the Thermo NSS box as described below 1 Select the acquisition mode Spectrum in the left menu 2 Open the tab Detector Status on the bottom right panel 3 Click on Advanced Status It la...

Страница 68: ...usser and inspiration taken from the original 7 page SEM manual from Dr Lukas Martin Many thanks to them Comments suggestions questions about this manual Contact Julien M Allaz julien allaz erdw ethz...

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