Tag Archives: X-ray photoelectron

AugerScan AES XPS software Tutorial

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AugerScan is RBD Instrument’s widely used software program which acquires and massages data on older Physical Electronics PHI X-ray photoelectron and AES Auger surface analysis systems and components. AugerScan is used in conjunction with the RBD Instruments 147 PC Interface unit. The 147 connects to the PC and provides a hardware interface between the software and the system hardware.

This post will explain all of the features and settings in AugerScan and how to configure the software for your particular system type.

augerscan-pulldown-menus

Beginning with the first pull down at the top of the status bar we have the File menu.

New New acquisition. Acquisition types include Alignment, survey, multiplex and depth profiles. You can also select the technique – XPS, AES or SIMS.
Open Open a previously acquired or saved file. You can save a file without acquiring it, in which case you can use it as a template for acquisitions of common settings.  For example, you may want to make a file called Elastic Peak which would be used to set the sample to analyzer distance when acquiring AES data.
Close Standard Windows command
Save Standard Windows command
Save as Standard Windows command
Import Imports AugerScan 1.X versions into the 3.X format
Export as Text Export file to ASCII format.  The ASCII format can be used for programs such as Excel and is also the format used by CASAXPS to read in AugerScan files.
Export All as Text Exports multiple files to ASCII format.
Export to Quases Export file to Quases formatQuases software download
Export all to Quases Export selected files to Quases format
Export to Multipak Export to older versions of the PHI Multipak format. Most new surface analysis systems use (or offer as an option) CASAXPS for advanced data massage functions.
Print Standard Windows command
Print Preview Standard Windows command
Print Setup Standard Windows command
Page Setup Standard Windows command
Create Reserved for future use, this command was intended for creating a new Windows object. However, Windows has changed so much that this feature is no longer relevant.
Recent Files A list of the most recent files that were opened. Currently this lists the last 4 files.
Exit Exits and closes AugerScan

The next pull down on the status bar is the Edit menu.

Copy Copies the open file to the Windows clip board. This is used to copy and then paste a survey into Word or some other windows program.
Copy as ASCII Copies the data in an ASCII format to the Windows clipboard.  This feature is used to copy and then paste data in Excel or some other windows program.
Paste Pastes the clipboard into another Windows program
Delete Not used
Mark/Track This is a cursor that displays the intersected energy in eV and the counts in the status bar. It is also used to select elements for the atomic concentration calculation for AES data.
Markers Displays the selected markers or endpoints. When selected the element marker will be displayed on the displayed data peak or in table form. When checked, the selection will be included in the atomic concentration calculation.
Select Endpoints Allows the user to select the endpoints used for the atomic concentration calculation. To use – move the cursor to the desired left end point. Press and hold the left mouse button. Drag the cursor to the desired right hand endpoint, release left mouse button.  This feature is helpful for selecting the peak of interest.
Endpoints Displays the selected endpoints
Annotation Standard Windows command
Element Table Tables used for atomic concentration calculation for AES and XPS, for markers only in SIMS. AES table includes sensitivity factors for 3, 5 and 10kV beam voltage. XPS sensitivity factors include peak and area modes for standard 15kV dual anode and monochromator X-ray sources.
Insert New Object Standard Windows command – seldom used command for inserting things like table or pictures into the data display.
Links Reserved for future use.
Object Reserved for future use.

The next pull down on the status bar is the View menu.

Toolbar The toolbars contain Icon shortcuts to commands and dialog boxes. Once you know these shortcuts they are easier to use than the pull down menus. The View Toolbar command allows the user to enable or disable the toolbars:

  • Main
  • Acquisition
  • Region Selection

We recommend that the tool bars are always selected.
Status bar This is the little box at the bottom of the Augerscan window. It displays pertinent information such as the cursor values and the status of data acquisitions.
Zoom The zoom feature allows you to view an area of interest in the data. To use the Zoom feature, move the magnifying glass cursor to the upper left hand corner of the area of interest. Click the left hand mouse button and drag the box to the lower right hand limit of the area that you want to view. Release the left mouse button. You can perform multiple zooms in.
Restore Un-zooms to the original data display.
Raw Data Displays the raw (original) data.
Transformed data Displays the massaged (transformed) data.
Cycles For depth profiles All region selection, selects cycles as the X axis on the displayed data.
Time Displays the depth profile X axis as time.
Depth Displays the depth profile X axis as depth. This is calculated from the sputter rate set in the Electron/Ion gun properties dialog box.
Expand X axis Expands the X axis display to allow room for text or an image.
Options Allows the user to set options for:

  • General
  • Line Style
  • Annotations
  • Fonts
  • Curve fitting
  • Graph

The next pull down on the status bar is the Acquisition menu.

Start Starts the selected acquisition
Stop Stops the acquisition at the end of the next sweep or cycle
Stop Now Stops the acquisition immediately and the data is not saved
Continue Continues the selected acquisition. This is useful if you want to stop a depth profile at an interface and then acquire a survey, then continue the profile.
Settings Displays all of the settings for the selected acquisition.
Edit Allows the user to remove regions or cycles from a depth profile, and edit the lower and upper limits in surveys.
Sample Properties This menu is where user can enter comments for samples. Typically this is used for 8 sample specimen stages on XPS systems.
New Survey Wide range scan, typically 30 to 1030 or 2030eV for AES and 1100 to 0 binding energy for XPS.
New Multiplex Series of narrow surveys, allows the user to acquire data only on the elements of interest.
New Depth Profile A series of multiplexes with combined with sputter etching acquires the elements of interest vs. depth.
New Alignment (peak) Used to set the elastic peak in AES, and to optimize the position of the sample or X-ray source in XPS.  Data is thrown out at the end of each sweep.
New 3 point depth profile For AES only, a 3 point depth profile makes it possible to get more elements into a depth profile than is practical with the standard depth profile. Since there are only 3 points selected per region (rather than the typical 20 to 50 points per region in a standard depth profile) you can get more elements into the same amount of acquisition time. Good for general trends only as a 3 point profile cannot use the atomic concentration calculation.
Technique Select the technique – AES ( Auger Electron Spectroscopy), XPS (X-ray photoelectron spectroscopy) or SIMS (Secondary Ion Mass Spectroscopy)
Options Allows the user to set options related to acquisitions. The most commonly used is the Prompt to Save after acquiring.

The next pull down on the status bar is the Data menu.

Revert to Raw Data Removes all previous data massage functions and restores the display to the original data.
Edit Raw Data A text editor, this command allows the user to edit out data spikes
Differentiate Normalizes background and displays data in peak to peak form.
Smooth Savitzky and Golay smoothing algorithm.
Convert to Counts Data in Augerscan is displayed in counts per second. This command converts the counts per second value to actual counts.
Shift Shifts the data up or down as specified by the use. Useful for compensating for small amounts of sample charging.
Depth Profile Smooth Smoothes Depth profile display. Similar to the data smooth command.
Deconvolute X-ray Line Fourier transform function that sharpens the XPS peaks
Satellite Subtraction Removes satellite peaks from data which improves the resolution (FWHM).
Baseline Removes the background from the selected endpoints.
Curve Fit Used for fitting hypothetical (possible) peaks into existing multiplex data.
Delete Curve Fit Deletes selected curve fit
Atomic Concentration Performs atomic concentration calculation. Peaks and endpoints need to be selected first. If the sensitivity factors are not in the element table you will need to add them before performing this function.
SIMS Relative Sensitivity Factor Used for SIMS data analysis
SIMS Atomic Density Used for SIMS data analysis
Options Set the number of points for smooth and differentiate, list the range for markers and select peak or area for XPS atomic concentrations.

The next pull down on the status bar is the System menu.

Hardware Properties Selects hardware properties for your system type. This is where you tell AugerScan the specific controls that your system has. Depending on the vintage and type of your system, most model numbers are located in the upper left hand corner of the electronic unit.  For card rack type systems, the model numbers are listed on the bottom of the mother board for each board set in the back of the electronics bay. You also set the input (detector), X-ray anode type and energy, and can calibrate the peak positions (scale factor). We provide calibration information with each 147 upgrade.
Multiplier Properties Sets the multiplier voltage for each technique. For AES, the multiplier can be set automatically for different electron beam currents by selecting the appropriate V/F preamp. Select the Preamp Defaults after first setting your preamp type (typically 96A/B) in the Hardware Properties dialog box.
Gun Properties For booking purposes only, this is where the user enters the typical settings for the electron and ion gun. The sputter rate value is used for the atomic concentration depth view.
Diagnostics Used to test the RBD 147 PC interface unit, for most users the DR11 test and DR11 data entry sections are useful for occasional troubleshooting or calibration of electronic components. To run the full diagnostics special jumper cables are needed.
Sputter Simple sputter timer is useful for sputter cleaning samples before analysis.
Ion Gun Control Opens up the ion gun control dialog box for digital ion gun controls such as the 77-070 (04-300 ion gun), 20-520 (Duoplasmatron ion gun) and 11-066/68 (04-303 and 06-350 ion guns).
Stage Control Controls the movement of digitally controlled specimen stages
Neutralizer Control Controls the 04-085 and 04-090 neutralizer
SIMS Positional Alignment Used for mechanically adjusting the SIMS optics to the position of the ion beam.
XPS Mapping Used for 5600, 5700 and 5800 XPS system that have the mapping hardware option. Due to the small count rate at the smallest aperture size this is not really a practical feature. New state of the art imaging XPS systems have much higher count rates while imaging and much better spatial resolution.
Automation Used primarily for digitally controlled specimen stages, this dialog box allows the used to stack up a number of commands and then run all of the commands as a batch.
Enable Batch Feedback Control No longer used.
Disable Batch Feedback control No longer used.

The next pull down on the status bar is the Window menu.

New Window Standard Windows command
Cascade Standard Windows command
Tile Horizontally Standard Windows command
Tile Vertically Standard Windows command
Arrange Icons Standard Windows command
Display All Regions Opens a window for each region in a multiplex or depth profile.  Currently you need to select this option after the acquisition starts or is completed. The next release of AugerScan will have an option for this to happen automatically.
Recent Acquisitions Lists the 4 most recent files.

The next pull down on the status bar is the Help menu.

Help

The original Help system (largely unchanged since Windows 3.1) was phased out in Windows Vista. The context-sensitive help – also known as “what’s this?” or “right-click” help cannot be replaced (this was the information you would typically see for each field in a dialog box, for example). However, for Windows Vista through 8.1, Microsoft does provide separate downloads for the legacy help system; it’s just no longer installed in the operating system.

You can find most of those files on this Microsoft support page (scroll down to “Resolution”) For security reasons, Microsoft no longer supports this help format at all in Windows 10, and there are no third-party solutions available.

However, we’ve translated most of RBD’s help to HTML for both AugerScan and AugerMap. In each case, simply  unzip the file to a convenient folder and run “index.html” in your browser.

augerscan-iconsThe images below list the commands for the shortcut Icons on the Main and Acquisition tool-bars. Once you learn these commands they make it very simple and fast to acquire and massage data.

Augerscan-Icons-vert

Augerscan Shortcut Icons

Ion Beam Induced Low Energy Electrons

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For the purpose of checking the performance of a surface analysis spectrometer such as a cylindrical mirror analyzer (CMA) or spherical capacitive analyzer (SCA), looking at an ion induced low energy electron peak can be extremely helpful. The peak typically occurs at about 20 to 50 eV and the size if the peak is directly related to both the alignment of the ion beam to the analyzer as well as the amount of ion current.

Checking XPS Performance

Set up an alignment for a range of zero to 100 eV kinetic. The eV range in binding energy depends on which anode energy you have selected in the software. See the table below.  Most systems use an Al anode, so the energy would be 1480 to 1380 eV (which is about 0 to 100 eV kinetic).

  1. Using a blank sample mount, position a sample to the focal point of the analyzer.
  2. Look under the Hardware Properties Menu for XPS and note the X-ray Anode type.
  3. Set up an alignment with the following parameters:
  • Upper Limit 1480 eV if Al is the anode, 1250 eV if Mg is the anode.
  • Lower limit 1380 eV if Al is the anode, 1150 eV if Mg is the anode
  • EV per step .5 (or the closest selection .5)
  • Time per step 20 ms
  1. Start the alignment and turn on the ion gun (no raster). You should have a low energy peak at around 20 to 50 eV kinetic.
  2. If necessary, reduce the ion gun beam current to prevent the detector from saturating. (You can increase the ion gun condenser lens setting or reduce the emission current in order to reduce the ion beam  current).

If you do not get the peak, then you have a problem with the analyzer or analyzer electronics. If you do, then the analyzer and  electronics are probably OK.

This is a very useful technique for isolating a low signal XPS problem between the analyzer and the X-ray source. You can also use the low energy peak to rough in the alignment of the ion gun to the XPS analyzer focal point.

Low energy peak of Mg anode

 

 

 

Checking AES Noise Level

Analyzer noise (noisy data) can be caused by these things:

  • Poor contact between the inner and outer cylinder terminating ceramics
  • Analyzer control
  • Electron Multiplier supply
  • Electron gun control or Electron gun high voltage supply

This technique will help isolate analyzer noise by determining if it is related to the electron gun, which in tern would be caused by the electron gun control or electron gun high voltage supply.

Overview

This procedure uses both the electron gun and ion gun as a source to generate low energy electrons. By comparing the relative noise levels, you can determine if the problem is related to the electron beam only, or both beams.  If it is related only to the electron beam, then the problem is in the electron gun control or electron gun high voltage supply.

If both the electron and ion beams are noisy, then the problem is either the analyzer control, multiplier supply or poor contact in the analyzer.  The analyzer control and electron multiplier supplies can be tested for noise using the appropriate calibration procedure.

 Procedure

This procedure was written specifically for a Physical Electronics 600 scanning auger system, but the principles can be applied to other systems as well.

Set up an alignment with these parameters:

Lower Limit 0, Upper Limit 100, EV per step 1, Time per step 20 ms

In AugerScan, go to the Multiplier Properties dialog box and uncheck the Auto EMS box. This will keep the computer from trying to automatically set up the electron multiplier voltage.

  1. In AugerScan, go to the Hardware Properties dialog box and make sure the input is VF1.
  2. With the electron beam on and set up for a normal elastic peak, start the acquisition and manually adjust the 32-100 CMA electron multiplier until you have a maximum count rate of approximately 100Kcps.  You will see a low energy peak around 20 to 50 eV depending on your sample.
  3. Use the yellow cycle stop button to end the alignment and then save the file.
  4. Blank the electron beam and turn on the ion gun. Do not use any raster.
  5. Start the acquisition and manually adjust the 32-100 CMA electron multiplier until you have a maximum count rate of approximately 100Kcps.
  6. Use the yellow cycle stop button to end the alignment and then save the file.

Compare the two files to determine whether or not they have similar amounts of noise.  In the examples shown below, then electron gun as a source exhibits more noise than the ion gun as a source.  In this instance the problem was isolated to a noisy emission supply in the 20-610 High Voltage supply on a 600 system.

Electron gun noise

 

 

 

 

 

ion gun noise

 

 

 

 

 

Ion Gun Alignment

On systems that do not have scanning electronic guns for TV imaging, you can use the low energy peak to center the ion beam with respect to the analyzer focal point. If you have scanning then you can simply look at the ion beam in real time on a SiO2 sample.

 AES Ion Gun Alignment Procedure (for non-scanning AES):

Using a blank sample mount, position a sample to the focal point of the analyzer (Elastic peak).

  1. Set up an alignment with the following parameters:
  • Lower limit 0 eV
  • Upper Limit 100 eV
  • Time per step 20 ms
  1. In the Multiplier Properties dialog box, un-check the Auto EMS Box.
  2. In the Hardware Properties dialog box, make sure the input is V/F1.
  3. On the 32-100, set the CMA multiplier switch to Analog and make sure the potentiometer is fully CCW.
  4. Start the alignment and turn on the ion gun (no raster).
  5. Slowly turn up the 32-100 CMA multiplier supply (or the 20-075 multiplier supply if you have an older system) until you have about a 100K cps low energy electron peak at 20 to 50eV.  This should occur at no more than 2000 volts on the multiplier (5.0 on the 32-100 potentiometer).
  6. Finally, adjust the X and Y position of the ion gun for maximum signal. The ion gun is now aligned to the focal point of the analyzer.

XPS Ion Gun Alignment Procedure:

Using a blank sample mount, position a sample to the focal point of the analyzer.

  1. Look under the Hardware Properties Menu for XPS and note the X-ray Anode type.
  2. Set up an alignment with the following parameters:
  • Upper Limit 1480 eV if Al is the anode, 1250 eV if Mg is the anode.
  • Lower limit 1380 eV if Al is the anode, 1150 eV if Mg is the anode
  • EV per step .5 (or the closest selection to .5)
  • Time per step 20 ms
  • Pass Energy 100 (or the closest selection to 100)
  1. Start the alignment and turn on the ion gun (no raster). You should have a low energy electron peak at around 20 to 50 eV kinetic.
  2. If necessary, reduce the ion gun beam current to prevent the detector from saturating. (You can increase the condenser lens setting or reduce the emission current in order to reduce the ion beam  current).
  3. Finally, adjust the X and Y position of the ion gun for maximum signal. The ion gun is now aligned to the focal point of the analyzer.  Once roughed in you can use a piece of TaO5 to check the alignment of the ion gun with respect to the system microscope because when you burn through the oxide layer you will see a blue ring on the TaO5 sample. RBD Instruments provides TaO5 samples for this purpose.