Carbon nanotube electron source based ionization vacuum gauge

The results of fabrication and performance of an ionization vacuum gauge using a carbon nanotube electron source are presented. The electron source was constructed with multiwall nanotubes, which were grown using thermal chemical vapor deposition. The electron emission of the source was stable in vacuum pressure up to 10(-7) Torr, which is better than the metal field emitters. The measurement linearity of the gauge was better than +/-10% from 10(-6) to 10(-10) Torr. The gauge sensitivity of 4 Torr(-1) was achieved under 50 muA electron emission in nitrogen. The gauge is expected to find applications in vacuum measurements from 10(-7) Torr to below 10(-11) Torr. (C) 2004 American Institute of Physics.