Ionization device and mass spectrometer

Patent metadata

Field	Value
Publication number	US-2022230865-A1
Application number	US-202017616495-A
Country	US
Kind code	A1
Filing date	May 11, 2020
Priority date	Jun 6, 2019
Publication date	Jul 21, 2022
Grant date	—

Abstract

The invention relates to an ionization device with an ionization space formed in a container, an inlet system for supplying a gas to be ionized to the ionization space, an electron source having at least one filament for supply of an electron beam to the ionization space, and an outlet system for letting the ionized gas out of the ionization space. Electron optics having at least two electrodes are disposed between the filament and the ionization space

First claim

1 . An ionization device, comprising:
an ionization space formed in a chamber, an inlet system for supplying a gas to be ionized to the ionization space, an electron source having at least one filament for supply of an electron beam to the ionization space, and an outlet system for letting the ionized gas out of the ionization space, characterized in that an electron optics comprising at least two electrodes is installed between the filament and the ionization space.

2 . The ionization device according to claim 1 , in which the electron optics is designed to focus the electron beam into the ionization space.

3 . The ionization device according to claim 1 , in which the electron optics is configured to measure an emission current of the filament at at least one electrode.

4 . The ionization device according to claim 3 , further comprising: a control device for controlling the emission current of the filament to a target emission current.

5 . The ionization device according to claim 1 , in which the electron optics has at least one switchable electrode for deflecting the electron beam away from an opening in the container.

6 . The ionization device according to claim 1 , in which the filament is disposed at a distance of at least 0.5 cm, preferably of at least 3 cm, in particular of at least 5 cm, from the chamber.

7 . The ionization device according to claim 1 , in which the electron source comprises two or more filaments that preferably each serve to supply one electron beam through opposing openings of the chamber.

8 . The ionization device according to claim 1 , designed to generate a pressure of more than 10 −4 mbar and not more than 1 mbar in the ionization space.

9 . The ionization device according to claim 1 , in which a flow conductance of the inlet system is greater than a flow conductance of the outlet system.

10 . The ionization device according to claim 1 , having a vacuum generation device configured to generate a pressure (p F ) at the filament of the electron source that is lower than a pressure (p) in the ionization space.

11 . The ionization device according to claim 10 , configured to generate a pressure (p F ) between 10 −8 mbar and 10 −4 mbar at the filament.

12 . A mass spectrometer for mass-spectrometric analysis of a gas comprising: an ionization device according to claim 1 , and a detector for detection of the gas to be analysed that has been ionized in the ionization device.

Assignees

• Leybold Gmbh

Inventors

• Brachthaeuser Yessica
• Benter Thorsten
• Thinius Marco
• Aliman Michel

Classifications

• H01J49/147 Primary

  with electrons, e.g. electron impact ionisation, electron attachment (H01J49/145 takes precedence) · CPC title

• H01J49/26

  Mass spectrometers or separator tubes · CPC title

• H01J49/025

  Detectors specially adapted to particle spectrometers (data acquisition H01J49/0036; detectors per se G01T, e.g. G01T1/28, G01T1/29) · CPC title

• H01J49/068

  Mounting, supporting, spacing, or insulating electrodes · CPC title

• H01J49/24

  Vacuum systems, e.g. maintaining desired pressures · CPC title