Patent · US Expired

Mass spectrometer, especially ICP-MS

US5625185A · kind A · utility

7Cited by
2References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 22, 1995
Grant dateApr 29, 1997
Priority date
Expiry dateSep 22, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2237/026
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In mass spectrometers with a plasma ion source (ICP-MS), a high ion current takes effect on the entrance of the ion optical system. The components provided there, especially lenses and apertures, have hitherto been made of steel. Atoms and ions are released from the surface of the components by a sputtering effect. This results in a correspondingly spoiling background signal and in losses in the quality of the analysis. To avoid the described effects, the components which are subjected to ion bombardment are made of graphite. The sputter rate and the ion yield of the carbon are much lower than those of steel (iron, nickel and chromium).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.