11-010 electron gun control operation and repair info

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This post is a compilation of information that we have provided in some of our newsletters about the Physical Electronics 11-010 electron gun control. These units are typically found with the 10-150/155 and 15-255G CMA auger and double pass x-ray photoelectron analyzers. As always, refer servicing to personnel trained to work safely with high voltage. The 11-010 contains potentially lethal voltages and currents! RBD Instruments provides repair services on the 11-010 electron gun control.
11-010 electron gun control basic operation:
1. Turn Emission voltage knob fully CW and the Filament current knob fully CCW.
2. Turn on the main power switch.
3. Turn beam voltage on, set it to Zero KV
4. Turn up filament knob until you have 1 mA of emission current.
5. Allow the filament to warm up, then increase to no more than 2 mA of emission current. Keeping the emission current at 1mA will length the analyzer filament lifetime.
6. If necessary, adjust the filament current limit pot (P1) so that you have no more than 2 mA of emission with the emission fully CW. This should happen at 6-7 turns of the filament pot. (Caution! The emission board is floating on the high voltage. Set the beam voltage to Zero kV before adjusting the filament current limit.)
7. Once the filament has stabilized, turn on the beam voltage to 2kV and reduce the emission voltage knob from fully CW to slightly CCW and obtain the best looking elastic peak. Also adjust the focus on the 11-010 as needed for optimal counts and peak shape.

Tech Tip: Setting your 11-010 Electron Gun Control with low enough current to run the 15-255G analyzer in pulse count mode

Set the emission current.

1. On your 11-010 electron gun control, set the emission knob fully CW.

2. Turn the beam voltage on and set it to 2 kV.

3. Slowly turn up the filament knob until you have 1 mA of emission current (about 7 turns on the knob). It will take a few minutes for the emission to stabilize. After it levels off, set it to no more than 2 mA.

Note: Never exceed 2mA of emission current or else the filament lifetime may be significantly shortened.

Set the emission current low enough for pulse count mode:

1. Turn the emission current knob fully CCW.
2. Turn the filament current knob ½ turn CCW
Note: This will be approx. 100nA of beam current
11-010 System Emission Calibration:
1. Turn beam voltage on, set to Zero KV
2. Turn Emission knob fully CW
3. Turn up filament knob until you have 2 mA of emission
4. If necessary, adjust the filament current pot so that you have no more than 2 mA of emission with the emission fully CW. This should happen at 6-7 turns of the filament pot.

11-010 Repair & Calibration
In General
This unit runs hot! The bottom plate should be vented to provide adequate ventilation.
Power Supplies
+90 Vdc +/- 10 Vdc (<30 mVac) at CR24 cathode, ref. to chassis
-90 Vdc +/- 10 Vdc (<30 mVac) at CR22 anode, ref. to chassis
+15 Vdc +/- .5 Vdc (<10 mVac) at any op-amp pin 7, ref. to chassis
-15 Vdc +/- .5 Vdc (<10 mVac) at any op-amp pin 4, ref. to chassis

BV Interlock
Short pins A & C together to turn off the power remotely.
Filament Supply
Rotate the filament current knob to the counterclockwise limit before applying power.
There are two over-current protection circuits. The filament current potentiometer  limits the current to 3.45 amps and the large wire wound resistor is a backup that limits (by shutting the 11-010 off)at 3.6 to 3.8 amps. To measure the filament current, connect a 5 amp ammeter between F1 and F2. Note: adjust the backup over-current sense first.
1. Adjusting both the filament knob on the front panel and the pot on the filament board to obtain enough current to trigger the backup over-current sense, set the wire wound resistor wiper so that the unit shuts down between 3.6 and 3.8 amps. Reset the 11-010 by turning the power off, then on again.
2. Adjusting the filament knob on the front panel until the first current limit is reached (not the backup), set the pot on the filament board so that the current limits at 3.45 amps.

Emission Supply
Note that the emission supply only turns on when the beam voltage is also on. Rotate the emission current knob to the counterclockwise limit before applying power.

1. Connect a 10 watt 8 Kohm resistor between F1 and V1. Measure and note its actual resistance. Isolate it well since it floats at the beam voltage.
2. Turn on BV (set to zero). Rotate the emission knob clockwise to its maximum. Calculate the current through the resistor be measuring the voltage across it. The meter should read approximately 6.25 mA (based on 50V of emission voltage).
3. Turn off the BV with the emission still on. The meter should drop to zero.

Beam Voltage
1. Use a high voltage probe (5 kV) to measure the voltage at F1 referenced to chassis ground.
2. Set the BV to 2 kV (Caution – high voltage is present!) and turn the Fine knob fully counterclockwise to the CAL position.
3. Turn on the BV. You should read 2 kVdc +/- 1 Vdc. If not adjust the pot on the HV board for 2kV.

Focus Voltage (V2)
The focus voltage should be adjustable (using the focus knob) from approximately 65% to 95% of the beam voltage.
Deflection
The BV does not need to be on for this test. The deflection output consists of DC offset signals (no waveforms) that vary from approximately -65 Vdc to +65 Vdc. The ripple should be less than 100 mVac. The signals do not necessarily correspond to the knob setting. Press the deflection power button to turn on.
1. Note the voltage at pins A and B as the X Deflection knob is adjusted to the limits. A and B are inverses of each other and each varies over the entire range.
2. Do the same for pins C and D by adjusting the Y Deflection knob.
3. Set the deflection pots for zero volts on the deflection output pins.

Troubleshooting Tips
1. Check for glowing filaments in the vacuum tubes when the power is turned on. A “cold” tube typically indicated either a bad tube or a bad connection at its base.
2. It is common for some of the 741 op-amps to blow in the deflection circuitry. Check those first if the deflection doesn’t operate properly.

11-010 Troubleshooting:
Problem: Blowing fuses when High Voltage is turned on.
Possible cause: High Voltage transformer shorted
Troubleshoot: Disconnect transformer output wires from circuit board.
Start with the Primary, then to the Secondary, to see if fuses still blow.
Problem: Filament Cut off circuit not working.
Possible Causes: Bad Opto-Isolator, Bad MPS3704, or I’ve now seen an open path on the floating ground cause this so check the resistance between the ground path on the HV circuit with Pin 14 or the tap on the 1 ohm resistor.
11-010 Emission Current Noise Reduction Modification
Due to aging components, many of the PHI 11-010 5 kV electron gun controls have developed a slight noise problem in the emission “chopper” circuit on the 623 board. This results in about 300 mV of 60 Hz ripple on the emission voltage, which translates into noise in the electron beam and Auger data.
Since the “chopper” circuit is never used (it was designed as a way to get N/E data with a lock-in recorder), a very simple solution to the problem is to simply bypass this circuit.
Procedure:
1. Unplug the 11-010 AC power cord and remove the cover.
2. Solder a jumper between Pins 17 and 18 on the 623 board . (The 623 board is located on the side of the 11-010, just above the filament supply board.)
This modification will reduce the noise level from about 300 mV to 50 mV or less and results in noticeably cleaner Auger data.

279905_11-010_Electron_Gun_Control_Component_Manual

PHI 15kV Dual Anode X-ray Source Outgas Procedure

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This is the procedure that I use to ensure proper outgassing and conditioning of the PHI 04-500 and 04-548 15kV Dual Anode X-ray source after installation or bake-out. It is a slight variation from the procedure in the 32-095 out-gas activate procedure.

–

Initial Installation

After installing the source, the system must be pumped down and baked out. If you are unable to bake-out the system, you should at a minimum wrap some heat tape around the flange on the source and heat it to 150 degrees C for a period of 8 to 12 hours.

After the bakeout is complete, reconnect the water lines and check for leaks by turning the x-ray source control on for 15 minutes. Sometimes there are small leaks that form a drop or two after 5 minutes. If there are no leaks after 15 minutes you can shut off the x-ray source control and connect the high voltage lead, the Teflon shield and the second cover.

Note: Make sure that the high voltage wire is tight and that the water flow is correct. See the info at the end of this procedure for more details.

Outgas the filaments

  1. Turn on the 32-095/096 x-ray source control and press the Outgas/Activate button. Select both anodes and slowly ramp up each filament to 2 amps. Now, using the ion gauge as a guide, increase the filament current in ½ amp increments until you see some out gassing (usually around 3 amps).
  2. Over the next hour, ramp the filament current up to 4.5 amps on both filaments. Allow the source to sit at 4.5 amps for a minimum of 4 hours, overnight is better.
  3. After the filaments have operated at 4.5 amps for at least 4 hours, ramp them up to 5.0 amps for 30 minutes.
  4. Press the Outgas/Activate button to turn the filaments OFF and let them cool for 15 minutes.
  5. Proceed to high voltage conditioning.

High Voltage Conditioning

  1. Make sure that the filaments are OFF.       Turn the high voltage rheostat on the high voltage control fully CCW and then press the red High Voltage button on the X-ray source control.
  2. Slowly turn the high voltage rheostat CW and bring the high voltage up to 5 kV. Observe the ion gauge for signs of out gassing and slowly bring the high voltage up to 8kV. The red light on the x-ray source control should stop flashing.
  3. Over the next hour or so, slowly bring the high voltage up to 16.5kV.   Observe the ion gauge for signs of out gassing. If you see the pressure rise, back off on the high voltage a little bit and wait a few minutes.   What works best is to bump up the high voltage in 500 volt increments and then to let if sit there while you go do something else.   Periodically come back and bump it up another 500 volts.   You can probably go up to 10kV fairly quickly, but after that you should go more slowly. The higher the kV, the more slowly you should go. Think of a rubber band that is being stretched. The further you pull it, the more likely it will snap.
  4. Note: The vacuum should be in the low 10-9 range when conditioning the high voltage. When the source outgases and the vacuum comes up into the mid 10-8 range, you should wait for the vacuum to go back into the 10-9 range. If the vacuum gets into the high 10-8 range the chances for an arc are good. It is best to bring it up slowly and not get any arcs as opposed to trying to force the outgas process. This takes time, be patient!
  5. Once you have the high voltage up to 16.5kV, leave it sit there for 30 minutes.
  6. Proceed to final conditioning.

Final Conditioning

  1. Turn on the high voltage and set it to 10kV.
  2. Power both filaments and bring up the power to 50 watts on both the Al and Mg anodes.
  3. Observe the ion gauge for signs of out gassing and let the source sit there until the vacuum returns to the low to mid 10-9 range.
  4. Increase the power to 100 watts per anode and increases the high voltage to 11kV.
  5. Slowly step the power up in 50 watt increments and the high voltage in 500 volts increments until you are at 250 watts per anode @ 15kV. This can take several hours.
  6. Leave the source sit there for an hour or more, until the vacuum returns to the low to mid 10-9 range.
  7. Decrease one anode to zero power and increase the other anode to 300 watts @ 15kV. Observe the ion gauge for signs of out gassing.   If necessary, wait for the vacuum to return to the low to mid 10-9 range.
  8. Set that anode power to zero and bring the other anode up to 300 watts @ 15kV and observe the ion gauge.
  9. Once both anodes can run at 300 watts @ 15kV and the vacuum stays in the low to mid 10-9 range, then the source is fully out gassed and can be operated normally.
  10. If you wish to go to 400 watts you will need to run it up slowly from 300 to 400 watts the first time and let it sit there for a while.

Revised outgas procedure for PHI dual anode x-ray sources and single anode mono sources.

Outgassing the filaments and conditioning the anode are essential steps needed to remove adsorbed gases from the filament area of any PHI x-ray source.

Recently I have seen a couple of instances where a 10-610 monochromator source was not properly outgassed and the result was a contaminated anode and very low counts. So degassing the anode is essential for proper operation.

To prevent anode contamination, the anode needs to be degassed per the PHI manual. However I have found that by changing the order of the outgas procedure steps that the amount of time it takes to outgas the source to full power can be significantly reduced.

The manual states that the outgas procedure sequence is as follows:

  1. Outgas the filaments
  2. Condition the high voltage
  3. Degas the anode

But from a practical standpoint it makes more sense to degas the anode before conditioning the high voltage. The reason is that a degassed anode is less likely to arc.

So the faster way to outgas an X-ray soure is:

  1. Outgas the filaments
  2. Degas the anode
  3. Condition the high voltage

Step 1. Outgas the filaments.

You need to outgas the filaments after new filaments have been installed or anytime the system has been brought up to air and baked out. For this procedure it is assumed that the system has been baked out. (The only bake out exception is if you have just replaced the 04-303 ion gun ionizer and backfilled the chamber with dry nitrogen).

  1. Turn on the 32-095/096 power.
  2. On the 32-095/6, press the Blue Out/Act outgas activate button.
  3. Select both filaments
  4. Select the Mg filament (or filament 1)
  5. Slowly increase the amps to 3.5
  6. Select the Al filament (or filament 2)
  7. Slowly increase the amps to 3.5
  8. Let the filaments sit there for a few minutes and then slowly increase each filament to 4.5 amps.
  9. Let the filaments sit at 4.5 amps for a minimum of 4 hours (overnight is best).
  10. After outgassing for at least 4 hours set the filament current to zero on both filaments and turn off the Out/Act outgas button by pressing it one more time.

Step 2 Degas the Anode

  1. Set the beam voltage to 500V and turn it on.
  2. On the 32-095/6, press the Blue Out/Act outgas activate button
  3. Select the Mg filament (or filament 1)
  4. Slowly increase the amps to 3.5 and then monitor the anode current (emission current) meter.
  5. VERY SLOWY increase the filament current until you get 1mA of emission current. Do not exceed 5 amps of filament current. Do not exceed 2mA of emission current.
  6. Monitor the ion gauge vacuum reading and wait until the outgassing comes back down then slowly increase the beam voltage to 1 kV. If necessary reduce the filament current to keep the emission below 2mA.
  7. In steps of 1kV bring the high voltage up to 10kV while adjusting the filament current as needed to keep the emission current below 2mA. Do this over a period of 10 minutes to several hours, depending on how much the anode outgasses. For best results keep the vacuum in the chamber in the low 10-9 Torr range. The higher the pressure from outgassing, the more likely an arc will occur.
  8. Once the anode has been outgassed to 10kV, turn the filament current to zero and set the high voltage to zero. Then switch to the other filament and repeat the procedure.

Step 3 Condition the high voltage

  1. Make sure that the Out/Act button is OFF and that the filament current is set to zero on both filaments.
  2. SLOWLY bring the high voltage up to 10kV while monitoring the vacuum chamber ion gauge.
  3. Step the high voltage up increments of 500V until you get to 16.5kV. When you see some signs of outgassing (the pressure in the vacuum chamber will come up) then back down the high voltage a little bit and wait until the vacuum recovers.
  4. Once you are able to get to 16.5 kV with no arcing, let the anode sit there for at least 20 minutes.

The X-ray source is now ready for normal operation.   For best results, start at a low power and kV such as 100 watts and 10kV.   You can step up both the power and the kV over a period of a few hours based on how much outgassing you see when operating in this mode. Once you are up to full power of 300 watts and 15kv the X-ray source can be brought up to full power quickly.

 

PS RBD Instruments provides all of the replacement parts for the 04-500 and 04-548 15kV dual anode x-ray sources. Contact us for more information.

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.