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Analytical Instrumentation Facility 2410 Campus Shore Drive

318 Larry K. Montieth Research Center www.ncsu.edu/aif

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Hitachi S-3200N Operating Instructions

Note that these are quick reference instructions for the Hitachi S-3200N SEM at the Analytical Instrumentation Facility of NCSU and not a treatise on SEM image formation and observation. For more general information see J.Goldstein, et. al., Scanning Electron Microscopy and X-ray Microanalysis, New York, Plenum, 2003.

Prior to starting, sign in the ESEM Users Log. Enter as much information as possible in the different fields so that the conditions you use can be replicated. Check Initial Settings

• EVAC Power (main breaker) should be ON (see Fig.1) • DISPLAY Power (main breaker) should be ON (see Fig.1)

o If either of the above are OFF, please contact Chuck Mooney (5-2348, 5-2932) or Dale Batchelor (5-5416) or Roberto Garcia (5-8628) before attempting to use the instrument.

• HV (high voltage to the emitter) should be OFF (HV button grey) • Robinson Backscatter Detector should be OUT (see Fig.2) • EDS Detector should be OUT (see Fig.2) • Stage Controls:

o X = 30 o Y = 20 o Z = Exchange position o Tilt = 0 o Rotation can be at any position

• Contrast and Brightness should be at minimum • Magnification should be at maximum • Scan 4 should be selected • High Vacuum mode (SEM) should be selected • Aperture set to 0 (no aperture) (see Fig.8)



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Figure 1. Evac and Display Breakers. Vent/Evacuate button is also shown. The button

should be in (yellow indicated) for vacuum and out for vent. The instrument should normally be left under vacuum.

Figure 2. X-Ray and Robinson detectors fully retracted. The X and Y controls of the stage should be at 30 and 20 respectively (use the numbers on the non-movable part of

the micrometer indicator). Z should be at the exchange position (white squares touching). Tilt should be at 0. Rotation can be at any position.



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Choose a Vacuum Mode

• Consider whether the sample is an insulator or a conductor. o In general, it is possible to image an insulator in high vacuum mode, but it

is easier to do so in low-vacuum mode. See J.Goldstein, et. al., Scanning Electron Microscopy and X-ray Microanalysis, New York, Plenum, 2003, pp. 207-240.

o It is also generally accepted that insulators can be coated with a thin layer of a conductor to improve operation in high vacuum mode. Two coaters are available for coating samples with metal. The typical metal sources are Au/Pd and pure Au.

• Conductor or coated sample: o High Vacuum (SEM) mode o Confirm:

Click on Vacuum Mode (Main Menu) The Vacuum window will appear SEM should be selected

• Insulator: o Low Vacuum (NSEM) mode o Change to NSEM mode:

Click on Vacuum Mode (Main Menu) The Vacuum window will appear Select NSEM

o The pressure can be set by clicking on Vacuum Set o The pressure can be varied in a range from 10Pa to 270Pa. A good

starting point for most insulators is 100Pa o The Robinson detector should be inserted AFTER the sample is inserted

and using the ChamberScope to determine that the sample will not touch the detector.

o In NSEM mode, Channel A is automatically set to BSE1, which is no longer used, and the Everhart-Thornley secondary electron detector is disabled. For instructions on using the Robinson Detector, see the Robinson Detector section below.

Inserting a Specimen • Select a sample holder and stub (see Fig. 3)

o The holder is the part that fits into the stage, the stub is the part upon which the sample is mounted

• Mount the sample on the stub (see Fig. 4) o Usually use carbon tape or carbon paint or silver paint to adhere the

sample to the stub • Mount the stub on the holder (see Fig. 5)

o Screw the stub into the end of the threaded rod



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Figure 3. Sample holder and stubs. The sample stub screws into the sample

holder

Figure 4. Carbon tape used to adhere sample to stub. On the right, a sample is shown held in place on a stub by a strip of C tape. It is acceptable to use more than one strip

of tape and to put more than one sample on the stub at a time.

• Adjust the specimen height o For general use, adjust the highest point on the specimen to the middle line

on the height gauge. This sets the specimen to a working distance of 23mm.

o For X-ray analysis, set the height to the second mark on the gauge for a working distance of 17mm.

o For high resolution use, see Chuck or Dale or Roberto



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Figure 5. Specimen height gauge. Loosen the locking collar on the sample holder to adjust the sample height. The specimen height should be set to the center mark on the gauge. This sets the working distance to 23mm. For X-ray analysis, set the specimen

height to the second mark for a working distance of 17mm.

• Turn on the Chamberscope and confirm that there are no samples currently in the instrument and that the detectors are fully retracted.

o Turn on the Chamberscope power button o Turn on the monitor o Adjust the illumination control as needed

• Confirm that the Z-stage control is set to the exchange position (EX) o The white squares will line up when the stage is at the exchange position

• Press the EVAC/AIR button (see Fig. 1) to bring the chamber to atmospheric pressure.

o The LOW light will turn on o The system will reach atmospheric pressure in approximately two minutes

• Carefully open the chamber o The stage will slide forward

• Insert the sample holder into the stage o Observe that the sample will not strike any detectors or the pole piece

using the ChamberScope



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Figure 6. Stage pulled out of chamber. Sample holder fits into circular hole in stage.

Make sure the sample holder is fully seated.

Figure 7. Make sure that the Z position of the stage is at the exchange position after

seating the sample before closing chamber.

• Confirm that the Z-stage control did not move and is set to the exchange position (EX), see Figure 7 above.

• Close the Chamber and push the EVAC/AIR button to evacuate the system o Hold the chamber door securely shut until the vacuum system starts

pumping. o Evacuation typically takes on the order of 3-5 minutes. o The vacuum gauge is on top of the Specimen Current Meter o There are two vacuum gauge outputs displayed on the gauge

• One is a Thermocouple gauge, which is the quarter-circle in the upper left corner of the gauge display. The thermocouple gauge’s range is from atmosphere to 1*10-3 torr.

• The other gauge display is a cold cathode gauge and will appear as a number in the main gauge display. The cc gauge will not be on until the vacuum is better than 1*10-3 torr.

o When the vacuum gauge displays 9*10-5 Torr, the system is ready for use



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Alignment and Setup It is recommended that a complete alignment be performed at the beginning of every SEM session. Initial Startup

• Turn on HV o The filament will turn on and be set to the last conditions used o Set the desired accelerating voltage

Method 1 • Click on E.Beam to open the E.Beam window • Click on Acc.Voltage • Select the desired accelerating voltage

Method 2 • Click on either the up or down arrows next to the HV

button to reach the desired accelerating voltage • Monitor the current accelerating voltage at the bottom of

the SEM screen o Set the desired beam current

Click on E.Beam to open the E.Beam window Click on Beam Curr. to open the Beam Curr. window Set the beam current by one of the following methods

• Multi-function knobs o X = beam current adjust o Y = fine beam current adjust

• Clicking on the up or down arrows • Click and drag the slider

Coarse current adjust is used for most adjustments Fine current adjust is typically only used for reaching a precise

current level as measured via a Faraday Cup and current meter • Confirm that the apertures are removed • Set the magnification to the minimum • Select the signal monitor “S”

o Bring up the brightness until the signal line just moves The signal line is the one that extend the entire length of the screen

o Bring up the contrast until a signal envelope is observed • Select a scan (TV1 or 2 or Scan1, 2, 3, or 4 or the reduced area scan) to obtain an

image. • Adjust the focus to obtain an image of the sample. It may be necessary to readjust

the brightness and contrast. o Note that the contrast and brightness should be minimized before shutting

down the instrument and should be low upon start up



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Electron Gun Alignment • Confirm that the magnification is minimum and the apertures are removed, i.e.,

set to 0 • Open the Alignment menu • Open the Gun Shift and Gun Tilt windows • Adjust the Gun Shift until the signal is maximized (brightest image)

o The gun shift can be adjusted with either the XY Alignment knobs on the knob set or via the mouse

• Adjust the Gun Tilt until the signal is maximized o The gun tilt can be adjusted with either the XY Alignment knobs on the

knob set or via the mouse • The Electron Gun should now be aligned and should not require any further

adjustment unless the accelerating voltage is changed. Objective Aperture Alignment

• Confirm that the beam current is set to the desired level o Click on E.Beam to open the E.Beam window o Click on Beam Curr. to open the Beam Curr. window o Select the desired beam current

• Determine which aperture is to be used o Aperture indicator and sizes are:

0 = no aperture 1 = 150um aperture 2 = 80um aperture 3 = 50um aperture 4 = 30um aperture

• Insert the aperture strip to the desired aperture by turning the large knob on the end of the aperture assembly clockwise. The aperture strip should be stepped one aperture at a time.

o The first step, 0 to 1, is a rotation of about 2 hours clockwise o Each subsequent aperture is selected by a further rotation of about 1 hour

• Coarse Center the aperture by adjusting the small knob at the end of the aperture assembly and the knob that is on the side of the aperture assembly

o Coarse Centering is completed when the signal observed on the SEM screen is maximized (brightest). If there is a range that appears to be maximized, adjust the aperture to the center of the range.



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Figure 8. Objective Aperture. To insert the aperture, rotate the barrel clockwise to the stop. The vacuum will pull the aperture in. Each stop in the clockwise direction inserts

the aperture strip one position. Aperture positions are 0 (no aperture), 1 (150um), 2 (80um), 3 (50um) and, 4 (30um).

• Fine center the aperture using the following procedure o Increase the magnification to 5000X or greater

Note that the fine adjustment should be made at or higher than the maximum magnification that is to be used with 5000X as a minimum.

o Turn on the aperture wobbler Click on Alignment to open the Alignment window Click on Aperture1 to open the Aperture 1 window

o The objective lens will automatically shift the focus above and below the sample

If the aperture is not perfectly aligned, the image will shift o Adjust the aperture by turning the aperture knobs (on the aperture

assembly) until no image shift is observed Note that this is not an electronic adjustment and that no changes

can be made in the Aperture 1 window The Aperture 1 window only turns on the wobbler!

• The objective aperture is now adjusted and should not need to be adjusted again unless the accelerating voltage or beam current are changed.

o If the image shifts during focusing, the aperture has come out of alignment and should be re-aligned.



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Stigmator Coil Alignment Note: -The stigmator coil alignment is not a critical alignment!

-The stigmator coil alignment does not affect the image quality! -The stigmator coil alignment is performed if the image shifts more than is acceptable during astigmatism correction -How much shift is acceptable is up to the individual user -Adjusting the stigmator coil alignment does not affect the astigmatism correction!

• If it is determined that stigmator coil alignment is needed perform the following: • Increase the magnification to higher than that to be used during the session and

focus o 5000X is the minimum magnification for stigmator coil alignment

• Choose a feature in the center of the image that can be observed during coil alignment

• Turn on the X stigmator coil wobbler o Click on Alignment to open the Alignment window o Click on Stig.X to open the Stig.X window

• Use the X and Y Alignment knobs to remove any shift from the image o Note that it is best to choose a feature in the center of the field of view as

the edges will become distorted during the wobbling process • Close the Stig.X menu when finished to turn off the wobbler. • Repeat with the Y stigmator coil wobbler

o Click on Alignment to open the Alignment window o Click on Stig.Y to open the Stig.Y window

• The stigmator coils are now aligned. If image shift is observed while removing astigmatism from the image with the stigmator knobs, then the stigmator coils need to be realigned.



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Final Focus • Use the Focus knob to obtain the best possible image

o To determine if the image is in focus it is important to adjust past optimum and then come back to optimum focus. Usually several iterations are needed to reach optimum focus.

o If any stretching of features are observed, then astigmatism needs to be removed from the beam

• Use the Brightness and Contrast knobs to adjust the image levels o Adjust the brightness and contrast using the signal monitor “S” o Best results are achieved if the signal observed just exceeds the top and

bottom signal adjustment lines • Use the STIGMATOR knobs to remove any astigmatism from the beam

o If any stretching of features are observed this will be required o First focus to the point that no stretching is observed o Then adjust the X STIGMATOR knob to bring out details and improve the

apparent focus in the image o Adjust the focus again to insure that no stretching is observed o Adjust the Y STIGMATOR knob to bring out details and improve the

apparent focus in the image o Adjust the focus to insure optimum focusing conditions o Usually, this process has to be repeated several times to reach optimum

conditions Stigmator adjustment is critical to obtaining high quality images! The astigmatism correction should be checked each time the instrument is focused! Data Collection

• Use the Revolution software to collect digital micrographs and X-ray data o For more information on Revolution see the 4Pi Revolution operating

instructions below. • Adjust the brightness and contrast for digital micrographs using the Survey mode

in Revolution • Collect digital micrographs using E-Image • Collect X-ray spectra using Probe • Collect X-ray maps using X-image



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Shut Down • Turn off any optional modes (i.e., raster rotation) • Turn off the beam (HV off) • Magnification to maximum • Brightness and contrast to minimum • Select scan 4 (slowest scan) • Objective aperture removed • Detectors set to fully retracted positions • Stage set to exchange position (Z = EX, Tilt = 0, X = 30, Y = 20) • Vent the chamber and remove the sample, then evacuate the chamber • Fill out the log and a work order form

Robinson Detector This section describes the use of the Robinson Backscattered Electron Detector. The default detector is the Everhart-Thornley Secondary Electron Detector. Other detectors are available – see Chuck for details. DANGER! Pay attention to the position of the Robinson Detector! The Robinson Detector inserts UNDER the pole piece and thus can easily be damaged! Repair or replacement is very expensive ($10,000)!!! Do not touch the detector with a sample or any part of the sample stage! Touching the detector will damage it! Pay attention to the position of the sample when using the Robinson Detector!

• The detector must first be inserted before use. Note the position of the detector in

figure 1. The detector should be left in the retracted position except when in use. To insert the detector:

o Turn on the chamberscope and observe that the sample and stage are not close to the pole piece. If in doubt, get help from Chuck or Dale or Roberto!

o Grasp the body of detector and lift the bottom guide rail, see Figure 9. o Slowly insert the detector until it is completely inserted

Do not let the detector slam into position! Ease the detector into place! The detector is inserted when the body of the detector touches the

flange • Once inserted, the detector must be chosen as the current input of the SEM

o Select the correct signal: Click on Display Mode to open the Display Mode window Choose Sig. Select to open the Sig. Select window Choose B (Full, Left)



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Figure 9. A shows the Robinson detector fully retracted. B shows the bottom rail being

lifted to allow the detector to be inserted. C shows the detector fully inserted.

Confirm that Aux2 is selected Close the windows

o Click on RUN to stop the SEM The SEM has stopped running when RUN becomes gray

o Click on B to Select Channel B o Click on RUN to start the SEM again

• Turn on the Robinson Detector o On the Robinson Detector Controller (Figure 10), push the Power button

to turn on the detector o Push the HV button to turn on the bias to the detector

IMPORTANT! Turn off the detector *before* venting the chamber. The detector will be damaged if it is not turned off before the chamber is opened!

• Setting the brightness and contrast

o Turn on the signal monitor (S) o The joystick on the detector controller controls brightness and contrast.

Contrast is up-down Brightness is right-left

o Using the signal monitor, adjust the brightness and contrast to obtain a good signal.

• Collect Digital Data with Revolution o Simultaneous BSE and SE images can be collected by using Channel A

for the SE detector and Channel B for the BSE detector and enabling the Channel 2 input in Revolution

o For more about imaging with multiple detectors see Chuck o For best results, use a working distance of 10-17mm



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Danger! Use the chamberscope whenever changing the sample height! It is very easy to damage detectors and/or the pole piece with the sample when adjusting the height!

• Turn off the detector after use and before the chamber is vented • Retract the detector after use

o Turn on the chamberscope to observe the position of the sample with respect to the Robinson Detector before retracting the detector

Figure 10. Robinson Detector Controller.

The Robinson Detector has a filter function that can clean up images, if the user is careful.

• The filter is a low pass filter o The Pass setting passes all frequencies of data to the SEM

High frequency noise can get through to the image using the Pass setting

Slow scans should reduce high frequency noise o Each setting after Pass (500kHz, 100kHz, 10kHz), cuts off the frequency

response above the selected frequency o Fast scanning requires high frequency response, so the image will not look

good at high scan rates if a low frequency filter is chosen, e.g., TV rate scans with a 10kHz filter are not good



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• To select a filter, push the Filter button on the detector controller o Each subsequent push of the button scrolls through the filter choices o Filter choices are: Pass, 500kHz, 100kHz, 10kHz

• To successfully use the filter; o Set the dwell time per pixel the same in both survey and image modes o Click on Survey and then push the filter o Choose the filter that produces the best image o In general, if the scan is slow enough, no filter will be needed o Turn the filter back to Pass for high speed imaging

The Robinson Detector can be used to collect images with accelerating voltages of 5kV or more. Digital Data Collection This section describes how to collect digital data using the 4Pi Universal Spectral Engine and Revolution software. Description of Digital Data Acquisition System An external controller by 4Pi, the Universal Spectral Engine (USE) is used to generate SEM scans, collect digital SEM images, and as the pulse processor for the EDS detector. The 4Pi controller is interfaced to a PC running Revolution software for the graphical user interface (GUI). The 4Pi system allows for the acquisition of digital images and linescans as well as collecting X-ray spectra in point, linescan, and mapping modes. Digital images can be acquired at up to 16384x16384 pixels x 16 bits. Revolution is freeware and facility users are encouraged to take a copy. A folder called “Revolution for Users” is on the computer desktop for this purpose. Documentation from 4Pi is included with the folder. Merely copy the folder with Revolution onto the computer that it will be used with and double-click on the Revolution.exe file to start the software. No drivers or installation is needed. Revolution Software Revolution can run all the time and there is no need to close Revolution at the end of a session. If Revolution is not running, start Revolution by double-clicking on the Revolution icon on the computer desktop. A window will appear that should indicate the version and if the software is communicating with the electronics (DXP = 1, SEM = 1, CCD = 0). Click on OK and the software will start. Revolution Operating Modes Under the Mode pull down menu, there are a variety of operating modes. Universal mode is the mode most users will want to use. Indeed, there is no reason to use any mode



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other than universal mode and the instructions below assume that the user is operating in universal mode. Before taking data with Revolution Enter the accelerating voltage in the space next to kV in the Revolution toolbar. The kV that is displayed will be shown in the bottom left of the micrograph next to the magnification entered. If the incorrect kV is entered, the micrograph will display the wrong accelerating voltage. In EDS mode, if the wrong kV is entered, quantitative results will be incorrect. If the sample current is known, this can be entered under current. The current setting is not terribly important. The current can be measured using a Faraday cup. The Mag option should be set to “Ask and Add.” If it is set to “Ask and Add,” then the software will ask for a magnification level prior to collecting a digital micrograph. If the software does not ask for a magnification level, then check the Mag. option and set it to “Ask and Add.” Digital Data Collection Setup The user may want to check the digital data setup prior to collecting data. To check or set any digital data collection settings, click on Setup in the Collection section of the tool bar. The Universal Preferences menu will pop up. A series of tabs will be visible at the top of the window with each tap representing a different type of data collection. Survey and E-Image Both of these functions are for digital imaging. Survey mode allows the user to observe the sample in order to set the brightness and contrast and make sure that the image is composed in an aesthetically pleasing manner. The scan size can be set with the Size pull down menu. A variety of scan sizes are available. The sizes displayed are in pixels. If the user desires a size that is not displayed, click on Edit Size and create the pixel size image that is desired in the Scan Size Setup window. Do not change the sizes that are available, rather, add a new size to the list. Since traditional SEM micrographs were collected on 5:4 aspect ratio Polaroid film, a 5:4 aspect ratio is recommended for micrographs. It is possible to integrate several frames together in E-Image mode. See Chuck for more details on integration. The Hitachi S-3200N does not seem to be particularly sensitive to if the Line Sync box is checked or not. The Image Channel Options box of the window shows which input channel is selected, any scaling options, and the type of data to be collected. The recommended settings are to leave Channel 1 enabled with no Autoscaling and 16 bit – Dwell (us) selected. The 16 bit – Dwell (us) selection in the data type pull down menu means that 65k gray scale images will be collected. The dwell time per pixel is shown in the number box



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immediately to the right of the pull down menu for data type. The larger the number, the longer the dwell time per pixel. More dwell time means more signal for a less noisy image and it also means that images will take longer to collect. Typically, satisfactory results will be obtained with a dwell time of 30us/pixel in E-Image mode. Good results are obtained in Survey mode with a 10us/pixel dwell time. This makes setting the brightness and contrast relatively quick. In Survey mode, the Show Waveform box should be checked. In E-Image mode, the Show waveform box should not be checked. It is recommended that the default save format is left as Revolution. This saves images as Revolution special files, which is not a problem as Revolution is freeware and can be freely distributed. If images are saved as Revolution images, then magnification information is also saved with the image. Measuring sizes of features becomes trivial with the measurement function (M in the tool bar). If images are saved in formats other than Revolution, the ability to quickly and easily make measurements may be lost. Recommended settings for publication quality images are listed below for the E-Image setup. Scan sizes: 1000x800, 1500x1200, 2000x1600, or 2500x2000 pixels

Frame Average: Typically unchecked. If the sample is charging, multiple fast frames, i.e., images taken with a low dwell time per pixel, can be averaged together.

Line Sync: checked Spatial Frame Lock: unchecked Channel 1: Autoscaling – None, Enable checked, 16-bit Dwell (us), 20. Channel 2: Autoscaling – None, Enable not checked, 16-bit Dwell (us), 1. Access Control: Unlock All Line Profile Option: Show line profile not checked Default Save Format: Revolution Save as Displayed: not checked

Digital Imaging To take a digital image, first set the brightness and contrast using Survey mode. Click on Survey mode and an image will appear at a relatively fast scan rate (controlled by the scan size and dwell time in the setup window) with a signal monitor shown in red in the center of the screen. Adjust the brightness and contrast such that all of the desired signal can be observed with the signal monitor. Generally, this will mean that the signal will extend almost all the way from 0 (bottom dashed red line) to 100% (top dashed red line). It is generally smart to turn the contrast down until the signal line is flat, set the flat line to zero, and then increase the contrast until the signal is satisfactory. Note that the image should be aesthetically pleasing no matter what the signal monitor suggests!



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Once the brightness and contrast are set, collect a digital image by clicking on the E-image button. A pop-up window will ask for the magnification. Enter the magnification from the SEM and either press the enter button on the keyboard or click on OK. An image will form in a new window. If the user is not prompted to enter a magnification, select “Ask and Add” from the Mag pull down dialog box. The image can be saved as either a Revolution file (recommended), a TIFF, a JPEG, or a BMP file. X-Ray Analysis For information on understanding and interpreting X-ray spectra, please refer to J.Goldstein, et. al., Scanning Electron Microscopy and X-ray Microanalysis, New York, Plenum, 2003. For more information on how the 4Pi Universal Spectral Engine handles X-ray analysis please refer to the 4Pi documentation. It is a good idea to have an overvoltage of at least a factor of two above the maximum X-ray energy that is to be collected, e.g., for a 8.04 keV Cu Kalpha X-ray, one would want the accelerating voltage to be at least 16kV with 20kV being a better choice. See Goldstein, et. al., for more information on overvoltage. It is important to set the accelerating voltage to that being used by the instrument in the kV window of the Revolution toolbar. In general, the working distance should be set to 17mm +/- 2mm to collect X-ray data. It is best to move the X-ray detector in to the bottom stop, which will maximize the solid angle of collection and enhance efficiency. To collect X-ray spectra, there are several methods with two being the most common. One is to zoom on the region of interest and collect a spectrum of the area, the other is to take an image and select points from which to collect X-ray data. Method 1. Focus on the region of interest (ROI) such that the ROI fills the entire field of view of the SEM. Click on Probe in the Revolution toolbar. An X-ray spectrum of the ROI will appear. Method 2. Collect a digital image. Click on the “Rectangle” button and draw a box around the ROI. Then right click on the box and choose to “EDX selected area.” An X-ray spectra of the ROI will be collected in a new EDS spectrum window. It is possible to select a single point with the point button. It is also possible to queue multiple areas to collect X-ray spectra by creating multiple ROIs and then right click on the image and choose “Queue EDX items.” Spectra will be created in the order in which the ROIs were placed on the image.



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Multiple spectra can be collected in a single spectrum file. This allows for easy data management since all the spectra for a single sample can be collected in a single file. If an EDS window is open, any new spectra will be collected in the open spectrum file. If a new window is desired, click on File -> New Catalog to open a new EDS window. If multiple EDS windows are open, the new spectrum will be collected in the active window, which will be the EDS window on top. Probe Preference Settings: The following preferences can be set in the universal preferences probe window. The most important is likely the collection time. The longer data is collected, the less noisy the spectrum will be. The following are typical settings for the collection of EDS spectra.

Preset(s): 60 or more is recommended. This is the duration of time, in seconds, over which the spectrum will be collected.

Type: LiveTime is recommended. Channels: 4096 Display: 2000 LLD (channels): 8 Access Control: Unlock All EDX Pulse Processor Time Constant: small TC = fast data collect and poor energy

resolution, large TC = slow data collection and better energy resolution Link all TC settings: checked Default Export Format: JPEG EM Beam Control: nothing checked or entered

Once a spectrum is collected, X-ray peaks can be marked by right clicking on the spectrum and choosing to “Open KLMs.” This will open the X-ray Spectra KLMs window, which allows the user to mark the location of specific elemental X-rays. If the X-ray line is known, the user can simply click on the element to mark its peaks. If the sample is unknown, the user can use the right-left arrow keys on the keyboard to scroll through the elements until the lines that correspond to measured peaks are observed. For more information on correctly identifying X-ray peaks, see the Goldstein et. al. reference or see Chuck or Dale or Roberto. For more advanced techniques, such as Quantitative analysis, X-ray mapping or Linescans, please see Chuck or Dale or Roberto.

2410 Campus Shore Drive 318 Larry K. Montieth Research Center

www.ncsu.edu/aif

Analytical Instrumentation Facility

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