This Balzers / Pfeiffer Turbo pump and controller compatibility chart was given to me by Dick Hagen of HSD Engineering about 25 years ago. It comes in handy when you are scrounging for turbo pumps or controllers on Ebay.
This blog post will show you how to repair a damaged 16 channel MCD anode ceramic on a PHI 5600 X-ray Photoelectron Spectrometer system.
The MCD anode ceramic is part of the MCD (multi channel detector) assembly. The anode ceramic has 16 channels where electrons with slightly different energies are counted. The 16 channel detector offers a higher count rate as compared to the PSD (position sensitive detector) and single channel electron multipliers that were used on earlier XPS systems.
There are surface mount resistors on the MCD anode ceramic that couple the positive (POS) voltage to the individual channel output ceramics. One of these surface mount resistors in particular provides the pathway for the multiplier POS voltage to the channel (chevron) plates. The POS contact is on both sides of the ceramic and they are connected via a gold plated through hole.
It is possible that over time (or when the chevron plates are replaced) that the gold plated pad can become electrically open in which case there would be no voltage applied to the chevron plates and, therefor, no XPS signal.
The picture below shows the location of the POS voltage gold plated through hole.
In this case, the gold was worn away from the gold plated through hole which resulted in an open circuit and no data. The picture below shows a close up of the gold plated through hole and the open area on the ceramic.
Besides not getting any data this problem was also evident as the resistance between the POS and NEG connections was open instead of the normal 15 to 20 meg ohms.
A new MCD anode ceramic costs about $700.00 and so I decided to first try and repair the contact using a thin strip of oxygen free copper foil
First I used a ceramic cutting wheel to flatten out the out edge of the ceramic to make room for the copper foil. Then I cut the small piece of copper foil so that it would cover the pad by the resistor and then be able to bend over the other side of the ceramic so that it could contact the outer gold ring. I pressed the copper so that it would be as flat as possible. Since there is a contact on both sides of the ceramic in the areas that the copper foil will cover, those contacts will hold the copper foil in place.
After reassembling the MCD assembly the multiplier POS to NEG resistance was 20 meg ohms, which is correct.
This repair method works well if you do not have a replacement MCD ceramic handy.
The PHI part number for the 16 channel anode ceramic is 619102 and the price as of January 2025 is $729.00
For more information on installing the Chevron plates into the MCD assembly refer to this blog post – https://www.rbdinstruments.com/blog/5600-xps-system-mcd-channel-plate-replacement-procedure/
This blog post includes a video that demonstrates the area of illumination for a PHI 04-548 dual anode X-ray source. That is, where the X-rays hit the sample.
The 04-548 dual anode source typically has one anode side that is Mg and the other side is Al. The older XPS systems that have an 04-548 X-ray source use a lens on the input to the SCA (Spherical Capacitor Analyzer) which determines the analysis area. For example the PHI 5600 XPS system can analyze areas as large as 10mm X 4mm down to 75uM.
The actual illumination area of the 04-548 dual anode X-ray source is quite large as shown in this video – 04-548 X-ray source illumination area.
Today’s state of the art XPS systems focus a small electron beam onto an aluminum target in conjunction with a mono-chromator to excite a very small area on the sample. Rather than exciting a very large area, today’s XPS systems excite a very small area. Down to just a few microns which make it possible to image the sample and analyze surface defects.