Category Archives: Operation and Calibration Procedures

Operation and calibration procedures for PHI (Physical Electronics) components

XPS and AES peak linearity adjustments

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This post is a compilation of some calibration tech tips that I have written over the years. The procedures listed below explain how to calibrate the following systems and units:

5600 and 5400 XPS systems, Double pass CMA XPS analyzers

Scanning Auger system, Auger analyzers

WARNING: Some of these procedures involve making adjustments in power supplies that have high voltage present. Always refer high voltage adjustments to personnel who have been properly trained in high voltage safety.

5600 and 5400 XPS systems pass energy and linearity procedure:

First, check the pass energy tracking:

Load a sample that has one side clean gold foil and the other side clean copper foil. Sputter the sample until there is no oxygen or carbon present.

Acquire a survey on clean gold from 90 to 80 eV; with low pass energy (5.85 for a 5600 or 8.95 for a 5400) at .025 eV per step.

Acquire another survey over the same range using higher pass energy (23.5 for a 5600 or 35.75 for a 5400) at .050 eV per step.

The 84.0 gold peaks should be in the same position. If not, adjust the pass energy tracking potentiometer and then reacquire the surveys. After a few iterations you should be able to get the peaks in both surveys to line up. It is not important where the energies are at this point, only that they are in the exact same position.

On 5600 systems the pass energy tracking potentiometer is located in the filter box that is connected under the SCA. CAUTION – The filter box has high voltage present. Refer adjustment to qualified personnel.

On 5400 systems adjust R36A on the pass energy board in the 80-360 SCA control in the card rack. This potentiometer is accessible from the front of the card rack without extending the pass energy card.

For older ESCA systems that use the 20-805, adjust P1 in the 20-805 – Caution, high voltage is present inside the 20-805! Refer adjustment to qualified personnel.

If you have a 20-810 digital analyzer control, adjust R81B4 on the pass energy card

Adjust the pass energy tracking potentiometer as needed to get the peaks lined up at both pass energies. The pass energy potentiometer will have a greater effect on the higher pass energy peak location.

After the pass energy tracking is correct- Use a low pass energy and acquire a multiplex on the Au 84.0 4f7 and the Cu 932.67 2p3 peaks.

Check the location of the Au 84.0 4f7 and Cu 932.67 2p3 peaks. The span between the peaks should be 848.67ev. If not, adjust the scale factor in the XPS Hardware Properties dialog box slightly, and re-acquire the multiplex. The scale factor has 4 decimal point resolution.

Adjust the scale factor as necessary to get the correct span between the Au 84.0 4f7 and 932.67 Cu peaks. This may take several iterations. The scale factor has a greater effect on the Au 84.0 4f7 peak than the Cu 932.67 2p3 peak.

If you are still running with the original PHI software you will need to extend the retard board in the 80-360 or 80-365/6 control that is located in the card rack. Caution, high voltage is present on the Retard board! Refer adjustment to qualified personnel.

Adjust the Work Function in the XPS Hardware Properties dialog box so that both peaks are in the correct locations. The work function is a linear offset that affects the high and low energy peaks equally. Make a note of the scale factor for future reference.

xps-copper-gold-peaks

xps-copper-gold-peaks

 

AES energy calibration when using a 20-805 Analyzer Control

This procedure will calibrate the AES peak energies and 2 kV elastic peak crossover.

Tools needed: Insulated adjustment screwdriver (pot tweaker), Copper foil or gasket material.

Procedure:

  1. Read this entire procedure before starting the calibration.
  2. Load a sample of copper foil into the system and set the beam voltage on the 11-010 electron gun control to 2kV.
  3. Position the sample to the focal point of the analyzer using the AES Align routine. At this point it does not need to be exactly at 2kV, just make sure that the peak is maximized.
  4. Sputter the sample clean. Note: If you do not have a sputter ion gun on your system, then scrape the sample with a razor blade or exacto knife before you load it into the system to remove the surface carbon and oxygen.
  5. After the sample is clean, re-acquire the elastic peak and re-check that the peak is at maximum counts and beast shape. Do not worry if it is not at 2kV as that will be adjusted later.
  6. From this point on, DO NOT MOVE THE SAMPLE!
  7. Acquire an alignment from 900 to 960 eV and differentiate the data. The peak should be at 920 differentiated. If not, adjust the scale factor in the AugerScan Hardware Configuration menu a little bit and re-acquire the alignment and check the position. After calibrating the copper peak position, reacquire an elastic peak alignment but do not move the sample. If the n/e peak is not at 2000eV, then adjust P1 in the 11-010 control.**

2kv-calibration-potentiometer-11010

2kv-calibration-potentiometer-11010

 AES energy calibration for 11-500A

Procedure:

1. Load a sample of pure copper.

2. If you are using AugerMap software, set the magnification to 10,000X and use the Area Scan mode to minimize sample topography effect on the Auger signal. Or set 20-070A to Spot Mode.

3. Perform an elastic peak alignment and adjust the Z axis sample position to obtain maximum counts and best peak shape.

4. Sputter the sample clean until no carbon or oxygen is present.

5. Re-acquire the elastic peak to ensure that the sample is at the optimum position: highest counts and best peak shape. When the elastic peak is differentiated, the positive and negative excursions should be equal and symmetrical.

6. From this point on, do not move the sample!

7. With the beam voltage at 2kV, acquire a survey from 30eV to 1030eV, using .5eV/step, 50 ms/point.

8. Differentiate the survey and check the peak positions against the correct values as listed in the PHI handbook or other reference. A typical value is 920eV for the high energy peak and 60eV for the low energy peak on copper.

9. Note: If using AugerScan software, you can simply adjust the scale factor in the AES Hardware Properties dialog box rather than adjusting the 11-500A. If necessary, adjust P3 on the 682 board for proper peak position on the high energy peak. You can acquire an alignment with a range of 900 to 940, .5eV/step, 15ms/point and do the adjustment in real time. For copper, set the n/e peak to approximately 917eV. When differentiated, the high energy Cu peak should be 920eV.

10. Acquire another survey and check that the differentiated peak positions are correct. Document the results for future reference and file it in the system calibration log.

11. Acquire another elastic peak, but do not move the sample!

12. If the elastic peak is not centered at 2kV, then adjust P9 on the 664 board in the 18-080 electron gun control until the peak is centered at 2kV. (Or P1 in the 11-010 control**)

From this point on, every-time you set the elastic peak, the sample will be at the focal point of the analyzer

aes-copper-peaks

aes-copper-peaks

Auger energy calibration on 600 and 660 scanning Auger systems

This procedure requires sliding the 20-610 high voltage supply out and removing the cover to gain access to the beam voltage offset potentiometer, R108. Turn off the 20-610 when sliding it in out or in, and when removing or installing the cover.

Procedure:

1. Load a sample of pure copper.

2. If you are using AugerMap software, set the magnification to 10,000X and use the Area Scan mode to minimize sample topography effect on the Auger signal.

3. Perform an elastic peak alignment and adjust the Z axis sample position to obtain maximum counts and best peak shape.

4. Sputter the sample clean until no carbon or oxygen is present.

5. Re-acquire the elastic peak to ensure that the sample is at the optimum position: highest counts and best peak shape. When the elastic peak is differentiated, the positive and negative excursions should be equal and symmetrical.

6. From this point on, do not move the sample!

7. With the beam voltage at 3kV, acquire a survey from 30eV to 1030eV, using .5eV/step, 50 ms/point.

8. Differentiate the survey and check the peak positions against the correct values as listed in the PHI handbook or other reference. A typical value is 920eV for the high energy peak and 60eV for the low energy peak on copper.

9. Note: If using AugerScan software, you can simply adjust the scale factor in the AES Hardware Properties dialog box rather than adjusting the 32-150. If necessary, adjust R58/G3 (AES fine gain) and adjust R61/H3 (AES coarse gain) for proper peak position on the high energy peak. You can acquire an alignment with a range of 900 to 940, .5eV/step, 15ms/point and do the adjustment in real time. For copper, set the n/e peak to approximately 917eV. When differentiated, the high energy Cu peak should be 920eV.

10. Acquire another survey and check that the differentiated peak positions are correct. Document the results for future reference and file it in the system calibration log.

11. Acquire another elastic peak, but do not move the sample!

12. If the elastic peak is not centered at 3kV, then adjust R108 in the Bertan 20-610 High Voltage power supply to center the elastic peak.

 

Calibration is complete.

From this point on, every-time you set the elastic peak, the sample will be at the focal point of the analyzer (maximum signal and best shaped peak), and all of the Auger peaks will be in the correct positions.

 

**– Caution, high voltage is present! Refer adjustment to qualified personnel.

 

20-805 analyzer control calibrations

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This post explains some tests and calibrations for the 20-805 analyzer control which is used on older Physical Electronics (PHI) ESCA, XPS and AES surface analysis systems. The 20-805 analyzer control is typically used to control the 15-255G and 25-260 double pass cylindrical mirror analyzers.

20-805 Analog AES Input Test Procedure

This section explains the procedure for testing whether or not the 0 to 10 volt drive signal from the PC137A or RBD147 interface unit is working properly.

Equipment needed: DVM and BNC adaptor cable

The 20-805 has a gain of 200:1 and the analyzer scale factor is 1.7. This means that the ratio between eV detected and the DC voltage applied to the outer cylinder of the analyzer is 1.7 to 1. For example, to measure a 1000eV electron,  588.823 DC volts must be applied to the outer cylinder.

To calculate what the Analog or Input voltage should be for a particular eV, use the following formula:

Analog or Input voltage = eV divided by 1.7 divided by 200.

Example: 2000 eV divided by 1.7 = 1776.47 divided by 200 = 5.8823 volts on the Analog or Input cable.

Procedure:

  1. Turn the power off on the 20-805 analyzer control.
  2. Remove the Analog Input cable and connect it to a DVM.
    1. Set up an elastic peak alignment with a lower limit of 100 and an upper limit of 100. (This will put the sweep voltage at a single fixed value).
    2. Acquire the alignment and measure the voltage on the Analog or Input cable. The voltage should be about .294 volts DC.
      1. Set up an elastic peak alignment with a lower limit of 2000 and an upper limit of 2000.
      2. Acquire the alignment and measure the voltage on the Analog or Input cable. The voltage should be about 5.88 volts DC.

If the Analog or Input voltage is correct, then the D/A on the PC 137A or RBD147 is working properly.

20-805 Pass Energy Supply Test

The 20-805 Pass Energy Supplies provide the proper voltages to the PHI double pass CMA when used in the XPS mode.

To test:

  1. Short out the Analog Input on the back of the 20-805 with a bnc shorting plug. This will ensure that the high voltage output is zero.
  2. Set the pass energy switch on the 20-805 to 100.
  3. Measure between the HV and IC connectors on the back of the 20-805. The voltage there should track the Pass Energy switch on the front panel with-in .5 volts.
  4. Check that the HV to IC voltage matches the front panel for all pass energy settings.
  5. Measure between the IC and OC connectors on the back of the 20-805. The voltage there should track the Pass Energy divided by 1.7 on the front panel with-in .5 volts.
  6. Check that the IC to OC voltage matches the front panel for all passed energy settings.
Pass Energy Setting HV to IC voltage IC to OC voltage

10

10

5.88

25

25

14.7

50

50

29.4

100

100

58.8

200

200

117.64

If the voltages are not correct, check the 20-805 Pass Energy Supply capacitors and TIP53 transistors.

The 20-805 gain is 200:1.   You can use AugerScan to send out specific voltages on the D/A output (analog input) cable –

1) With the RBD147 on, run AugerScan.
2) Select “Diagnostics” from the “System” menu.
3) At the bottom of the dialog box, make sure the option for “Hexidecimal” is checked.
4) In the Address field for RBD147, enter 10
5) Individually enter the following in the Data field, and hit the Write button for each while checking the 20-805 control voltage:

8000 (0 V)
9FFF (1.25 V)
BFFF (2.5 V)
FFFF (5 V)
7FFF (10 V)

AES Calibration when using a 20-805 Analyzer Control – For a 10-155 or 15-255G Analyzer.

This section explains how to calibrate the AES peak energies and 2 kV elastic peak crossover.

Tools needed: Insulated adjustment screwdriver (pot tweaker)

Copper foil or gasket material.

Procedure:

  1. Read this entire procedure before starting the calibration.
  2. Load a sample of copper foil into the system and set the beam voltage on the 11-010 electron gun control to 2kV.
  3. Position the sample to the focal point of the analyzer using the AES Align routine. At this point it does not need to be exactly at 2kV, just make sure that the peak is maximized.
  4. Sputter the sample clean. Note: If you do not have a sputter ion gun on your system, then scrape the sample with a razor blade or exacto knife before you load it into the system to remove the surface carbon and oxygen.
  5. After the sample is clean, re-acquire the elastic peak and re-check that the peak is at maximum counts and beast shape. Do not worry if it is not at 2kV crossover, that will be adjusted later.
  6. From this point on, DO NOT MOVE THE SAMPLE!
  7. Acquire an alignment from 900 to 960 eV and differentiate the data. The peak should be at 920 differentiated. If not, adjust the scale factor in the AugerScan Hardware Configuration menu a little bit and re-acquire the alignment and check the position. A large scale factor number will move the peak down in eV.
elastic-peak

elastic-peak

  1. Re-peat and adjust the scale factor as necessary until the differentiated copper peak is at 920eV.
  2. Change the alignment settings to 2kV default and re-acquire the elastic peak. But, DO NOT MOVE THE SAMPLE!  If the peak is not at 2kV, then adjust P1 in the 11-010 to move the peak so that it is at 2kV. Caution! There is high voltage present in the 11-010, do not perform this adjustment unless you are qualified to work on high voltage.   Refer servicing to qualified personnel.
beam-voltage-adjustment-potentiometer

beam-voltage-adjustment-potentiometer

Location of P1 in the 11-010 Electron Gun Control is shown above.

 

  1. Once you have the 11-010 adjusted to 2kV, change the beam voltage to 3kV and acquire a survey from 30eV to 1030eV, 1 eV per step, 50 ms per point, and 3 sweeps.
  2. When complete, the survey should look like the date below after it is differentiated:
auger-copper-data

auger-copper-data

Calibration Complete!

Need more help with your 20-805?  Contact us.

Measuring electron beam diameter

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This procedure will allow you to determine the electron beam diameter diameter on scanning auger electron spectrometers using the line scan feature of AugerMap software and the magnification standard (or, a straight edged sample). Although written for scanning auger electron spectrometer systems, the principle is the same for SEMs – scanning electron microscopes – measure the slope across an edge at a known magnification.

1. Insert the beam size standard into the system and perform an elastic peak alignment on the top surface of the sample to ensure that the sample is at the correct Z position with respect to the analyzer.  Do not tilt the sample.

set-elastic-peak

Set elastic peak

 2. Next, change the beam voltage to 10KV and adjust the electron gun parameters for a good image at 5000X or higher magnification.

3. if so equipped, adjust the Condenser and Objective steering plates for minimum movement. (If an SEM, rock the lenses).

4. Ensure that the image is in the best possible focus.

5. Lower the magnification to the lowest possible setting and move the beam size standard to the center hole to find the grid and adjust the Z position until the grid is in focus.  The sample is now at the correct focal point on the analyzer. This is a good trick that you can use on any scanning auger system – if you first set the elastic peak and then the focus, as long as you mechanically bring the sample back into focus after moving to a different location on the sample (and do not change the focus knob or settings in the software), the sample to analyzer distance is still correct.

6. Set the magnification to 100KX and fine-tune the focus and stigmators as required. The sample can be moved on either the X or Y axis until you are able to line up on one grid line.

7. Obtain an SED video map and use the quantization feature if necessary.

8. Select the line scan feature in AugerMap and draw a line horizontally across the grid line.

9. For AugerMap1, Add region – SED line.

10. Select Video input; point one ms per step, number of sweeps one, and resolution 256 points per line.    For AugerMap II, select SED video map.

auger-map-2-sed-dialog-box

AugerMap 2 SED dialog box

 

 

 

 

 

auger-map-sed-dialog-box

Auger Map version 1 SED dialog box

 

 

 

 

 

 

 

 

 

 

 

11. Acquire the line scan.

12. After the line scan is completed it will show a display of signal intensity on the Y-axis vs. distance scanned on the X-axis. At 100KX magnification, this distance is 1uM, or, 10,000 angstroms. By determining the slope of the beam diameter as it crosses the edge of the sample, the beam diameter can be determined.

13. Print out the line scan and use a ruler to determine the top 20% and bottom 20% of the line scan. Draw a line across the top 20% and bottom 20% of the line scan.

14. Next, draw a line on the slope of the beam diameter as it drops down or up between the 20% lines.

15. Determine the distance between the slope of the line at the top of the scan and the bottom of the scan.  This distance represents the beam diameter in relationship to the full scan (10,000 angstroms at 100KX).

16. The example below shows in detail how this measurement is calculated.

beam-size-measurement

Beam Size Measurement

 

Perform this measurement anytime that you wish to know the size of the electron beam diameter for any given set of conditions.  If the beam size is too large to see one grid line, you can reduce the magnification to 50KX, in which case full scale on the X-axis would be equal to 20,000 angstroms.