AVS 47th International Symposium
    Vacuum Technology Wednesday Sessions
       Session VT-WeP

Paper VT-WeP4
Continuous Determination of the Gas Composition during Pump-down of Vacuum Chambers

Wednesday, October 4, 2000, 11:00 am, Room Exhibit Hall C & D

Session: Poster Session
Presenter: N. Mueller, Balzers Instruments, Liechtenstein
Authors: N. Mueller, Balzers Instruments, Liechtenstein
P. Schoch, Balzers Instruments, Liechtenstein
Correspondent: Click to Email
The gas composition during pump-down of vacuum chambers starting at atmospheric pressure is an important information for the evaluation and design of pumping stations. Nevertheless, this composition is rarely determined on-line, as there are no sensors available that directly allow for gas specific analysis over a wide pressure range. To overcome this problem, a differentially pumped quadrupole mass spectrometer with a unique inlet system has been developed. This instrument allows for continuous gas analysis in the pressure range from 1000 mbar down to 1E-3 mbar. Pump-down curves of different pumping stations (e.g. turbo-pumped systems with rotary vane pumps, diaphragm pumps etc.) have been determined. The results of these analysis will be presented and discussed.