AVS 61st International Symposium & Exhibition
    Vacuum Technology Monday Sessions
       Session VT-MoM

Paper VT-MoM11
A Systematic Study of Long-Term Vacuum Gauge Performance

Monday, November 10, 2014, 11:40 am, Room 303

Session: Vacuum Measurement, Calibration, and Primary Standards
Presenter: Gerardo Brucker, Granville-Phillips Vacuum Products
Authors: G.A. Brucker, Granville-Phillips Vacuum Products
S. Heinbuch, Granville-Phillips Vacuum Products
T.C. Swinney, Granville-Phillips Vacuum Products
Correspondent: Click to Email
Cold Cathode Ionization Gauges (CCIGs) have been the subject of numerous investigations throughout several decades. The free-running characteristics of their pure electron plasma, combined with the in-depth investigation of this phenomenon interacting with the interior of these devices, have led to numerous theories and speculation regarding the factors that regulate the long term performance of the gauges. Our laboratory has become increasingly interested in extending gauge lifetime through improved design and in the development of innovative dose calculation methodologies that can provide an adequate estimation of gauge remaining lifetime. We are particularly interested in understanding the phenomena that lead to drifts in gauge sensitivity with dose and specific gas chemistry. During our long term studies, gauge sensitivity is tracked over time against dose and the most modern surface and chemical analysis methodologies are employed to detect and understand the physico-chemical changes that take place at the internal electrodes. In this presentation we will demonstrate that while attempting to understand changes in gauge sensitivity it is equally important to consider changes in the magnetic as well as the internal electric characteristics of cold cathode gauges. Prior work by other groups has focused heavily on the influence of surface chemistry modifications. Our recent work will demonstrate that equal attention must be paid to the internal magnetic properties to fully account for long term changes in sensitivity.