Avac Engineers

We, at Avac Engineers, manufacture 2 types of UHV Systems, such as UHV Pumping Systems & UHV Processing Stations. The improved ultra high vacuum (UHV) pumping systems and leak detectors of this type uses helium as a tracer gas by the introduction of dry nitrogen. The invention is an improved leak detector that increases the leak detection sensitivity to 10-13 atm cc s-1. The leak detection sensitivity is improved by completely eliminating the need for or frequent replacement of o-rings, equipping the system with oil-free pumping systems, and by introducing a measured flow of dry nitrogen to keep the system free of helium and hydrogen background. The addition of dry nitrogen to the system reduces back streaming of atmospheric helium in the case of leak detectors and hydrogen in the case of UHV pumping systems even though there is only a limited compression ratio at the pumps for helium or hydrogen.