A blog on the repair, operation and calibration of surface analysis systems and components including electron spectrometers, sputter ion guns and vacuum related hardware. Click on the Index tab below to see a list of all posts. Visit our website at http://www.rbdinstruments.com
RBD Instruments provides a refill service for the 25cc Argon gas bottles that are used on PHI (Physical Electronics) 04-303 and 06-350 ion guns on X-ray Photo-electron and Auger Electron spectrometers.
This blog post will describe how to install the Argon bottle
and pump out the small volume of air that is between the bottle valve and the
leak valve. That small volume of air
needs to be pumped out in order to prevent contaminating the argon in the new
The RBD part number to refill your 25cc Argon gas bottle is Argon25ccRP. We can provide you with an exchange bottle which you can install on your ion gun’s leak valve and then return your empty bottle to RBD. We also provide new bottles that do not require an exchange (contact us for a special offer on new argon bottles that runs until the end of July).
Make sure that the leak valve is closed (fully CW and the arm should be parallel with the valve body).
Close the green valve on the bottle (turn fully CW).
Remove the six cap head screws that seal the bottle to the leak valve.
Remove the bottle.
Make sure that the green valve on the new bottle is fully closed (CW). It should be very tight.
Use a new 1.33” copper gasket and install the new Argon bottle to the leak valve. If the old copper gasket is stuck to the leak valve flange, use a needle nose pliers to remove the old gasket. Do not use a small screwdriver as that can damage the knife edge. Tighten the 6 cap head screws evenly.
Next, we will pump out the small volume of air that is between the leak valve and the green valve on the gas bottle. You could just slowly open the leak valve and bleed the air into the chamber over a period of a day or two, but this procedure will pump that volume out in just a few minutes.
With the turbo pump ON, pump out the load lock. You can do that with the AVC remote by pressing the Pump Intro button, or by manually opening V3 on the auto valve controller. We will be using the turbo pump to pump out the chamber and so need to first pump out the load lock.
With the load lock pumped out (let it pump for 5 minutes or more), turn the high voltage OFF on the ion pump controller. If your system has a Boostivac you can set the HV switch from Run to Standby.
Press the I/T 3 button on the DIGIII ion gauge controller. That will turn the filament OFF but still leave the power to the DIGIII on.
With the green valve on the argon bottle still closed, open the leak valve 2 turns CCW. That will start to bleed air into the chamber.
Manually open V1. The turbo pump will now be pumping on the chamber.
Fully open the leak valve by turning CCW another 4 to 6 turns.
The turbo pump may spin down slightly. You should have 5 bars on the AVC remote after just a minute or two. Let the turbo pump on the chamber for about 5 minutes.
After 5 minutes, press the I/T 3 button on the AVC to turn the ion gauge back on. You should be in the low 10-5 to mid-10-6 Torr range.
Flash the TSP for 2 minutes. Let the vacuum improve for a minute or two.
Start the ion pump high voltage. For a Boostivac, set the HV switch to Start, then to Run. The ion pump should stay on and the vacuum should be improving rapidly.
Manually close V1. The turbo pump is now isolated from the vacuum chamber.
Once you are in the low 10-8 Torr range, close the leak valve by turning it fully CW. The arm should be parallel with the valve body. Do not over tighten the leak valve.
With the leak valve closed (fully CW), open the green valve on the argon bottle by turning it CCW 1 full turn. You may need to use a pliers as these valves are closed very tightly once filled with argon. When the green valve is open the small volume between the green valve and the leak valve will be charged with argon.
Installation is complete. The vacuum will continue to improve and in 24 hours or so should be fully recovered to where the vacuum was prior to installing the new argon bottle. Even the small amount of air that was bled into the chamber has enough water vapor to degrade the chamber vacuum.
COVID-19 pandemic related travel restrictions have made it
much more difficult to perform field service maintenance on scientific
equipment such as XPS X-ray photoelectron spectrometers.
RBD Instruments currently offers technical support, where an RBD engineer works over the phone and internet with on-site technicians to troubleshoot and repair problems with older PHI surface analysis instrumentation. But technical support can be a slow and tedious process because the customer’s on-site technician needs to describe the system components and performance as part of the trouble-shooting process.
RBD also normally offers on-site field service repair services, where an RBD engineer travels to the customer’s site. But with the COVID-19 travel restrictions, all field service is currently on hold.
The next best thing to actually having an RBD engineer on-site would be to have a remote-controlled camera so that the RBD engineer can see the instrument in real time. Consider this to be enhanced technical support or virtual field service.
Remote controlled virtual robots are very cool (think Big Bang Theory Sheldon’s virtual presence episode) and would allow the RBD engineer to be in the lab virtually. But the telepresence robots are expensive and also might not be able to move around safely in a lab environment.
A much less expensive option would be a remote-controlled wireless camera with speakers. For only $50.00, this option would still give the RBD engineer more control over the camera than what is possible with cell phones and Skype. When the RBD engineer can see the equipment in real time more easily, the better the technical support result will be.
Until COVID-19 travel restrictions are eased, virtual field service is one possibility for repairing and maintaining scientific instruments such as XPS surface analysis systems and components. And going forward once COVID-19 is no longer an issue (hopefully in the not too distant future), virtual field service may become more common just for the cost savings compared to traditional field service.