Key design points for UHV and XHV
• It is very important to utilize materials with low hydrogen desorption rates and permeabilities. Stainless steel is not a good choice because of its very high solubility and very high hydrogen content. Aluminum is a great cost-effective option. Titanium is also very good, particularly if you are needing to bake at a very high temperature.
• Designing systems with the proper conductance is critical to achieving these very high vacuum levels. The mean free path of gases (the distance a gas molecule will travel before hitting another) are extremely long which means that conductance becomes very important. Big unobstructed pumping ports are essential because confined geometries may collect gas.
• Pumping is very important. The kinds of pumps can vary from scroll & turbo to ion, TSP, and NEG. There have been, however, newer specialized turbo pumps that are close to reaching XHV, provided they are combined with excellent backing pumps.
We offer UHV and XHV engineering and design services. Our comfort with materials beyond stainless steel and our deep knowledge of these materials equips us to properly design your UHV and XHV vessels. We also have full manufacturing capacity and can build what we design. We understand that the design must, of course, be buildable and we have been doing that for over 20 years. We look forward to talking with you.