[labnetwork] Cleaning a contaminated UHV chamber

[Saba Sadeghi]

Dear colleagues,

I have found a contamination in the loadlock of our UHV system with base pressure of 5E-9 mbar.

I am almost certain the contamination is a type of PFPE (fluorinated) grease as it didn't dissolve in 4 types of solvents (hexane, IPA, acetone and toluene) but I have sent a sample to EAG for further analysis.

Solvents for this type of grease are fluorinated fluids like:  Galden or Fluorinert or supercritical fluids.

My question is how should I proceed with cleaning, do you have a method to suggest? is cleaning a UHV chamber something that is possible to implement in the house?

Also, what do you think of using a dry-surface cleaning using CO2 snow?

As always I appreciate your input.

Best,
Saba Sadeghi, PhD
Quantum Devices Fabrication Scientist
Email: saba.sadeghi at uwaterloo.ca