Ionization vacuum gauge with a carbon nanotube field electron emitter combined with a shield electrode

The applicability of carbon nanotubes to an electron source for a Bayard-Alpert type vacuum gauge has been investigated. Three gauge configurations are designed to optimize the gauge performance. The optimized gauge, in which an additional shield electrode is fixed on a gate electrode, exhibits good measurement of linearity between ion Current and system pressure from 10(-7) to 10(-2) Pa. A gauge sensitivity of 0.05 Pa-1 has been achieved under 100 mu A emission current for nitrogen, comparable with 0.07 Pa-1 of commercial ionization gauges. (C) 2009 Elsevier Ltd. All rights reserved.