MASS SPECTROMETRY METHOD AND DEVICE IN EXTREMELY HIGH VACUUM

摘要

PROBLEM TO BE SOLVED: To prevent reduction of ion pass probability in an ion energy analysis part and generation of a great amount of gas due to a collision of thermoelectrons against chamber walls and attain an accurate mass spectrometry sequentially from a high vacuum area to an extremely high vacuum area. ;SOLUTION: This method performs a mass spectrometry in which ions are extracted from an ion generating part 2 for generating ion by an impact of thermoelectrons irradiated from a filament to a grid 12; the ions extracted are selected in an ion analysis part 3 followed by mass analysis in a mass separation part 4; and the ions analyzed are guided to an ion detection part 5 for detection. A Bessel-box type energy analyzer is used in the ion energy analysis part 3. A quadropole mass analysis tube is used in the mass separation part 4. Potentials of a final electrode 3e at an ion outlet of the Bessel-box type energy analyzer and a central electric field of the quadropole mass analysis tube are set on an approximately equal positive potential.;COPYRIGHT: (C)2000,JPO