Mass spectrometric evaluation of the desorption properties of some glasses under high applied voltage conditions

Abstract

The manufacture of vacuum devices such as lamps, electronic tubes and displays requires a careful evaluation of the desorption properties of glasses under specific operating conditions. An exceedingly high gas load can detrimentally affect the vacuum and reduce the overall device performances. In the present study, the effects of the application under vacuum of high voltages (3–9 kV) on a CRT and two soda lime glasses were investigated, as a function of the glass temperature (60–100 °C). Outgassed species were collected by a quadrupole mass spectrometer which was mounted with the ion source close to and in direct view of the sample, to minimize the reactive gas species loss due to surface interactions and recombination. The release of oxygen and oxygenated gases from soda lime glasses upon high voltage application was measured, providing some evidence that electrolytically induced ionic transport phenomena take place through the glass network under these conditions. A comparatively lower outgassing rate from the CRT glass was measured.