Cone-shaped orifice arrangement for inductively coupled plasma sample introduction system

摘要

A mass analysis system including a sample inlet arranged to introduce a sample and an ion source coupled to the sample inlet and arranged to ionize a portion of the sample into ions. The system also includes a sampler element having a sample orifice arranged to receive the sample ions into a first vacuum chamber. The system includes a skimmer element having a skimmer orifice arranged to receive the sample ions from the first vacuum chamber into a second vacuum chamber where the skimmer orifice is of a first size. The system further includes a third cone element having a third cone orifice of a second size arranged to receive the sample ions from the second vacuum chamber into a third vacuum chamber where the third cone is configured to allow a continuum flow of ions through the third cone orifice. The third chamber includes an ion optics assembly and mass analyzer.

主权项

1. A mass analysis system comprising:
an inductively coupled plasma and a sample introduction system arranged to ionize a portion of a sample into ions, a sampler element including a first orifice arranged to receive the ions into a first vacuum chamber, a first skimmer element having an ungrounded electrical bias and including a second orifice arranged to pass the ions from the first vacuum chamber into a second vacuum chamber, and a second skimmer element including a third orifice arranged to pass the ions from the second vacuum chamber into a third vacuum chamber, the third vacuum chamber including an ion optics assembly for passing the ions to a mass analyzer comprising a quadrupole mass spectrometer, the third orifice being configured to allow a continuum flow of ions to the mass analyzer, wherein the second skimmer element is biased at about ground potential to shield the first skimmer element from downstream extraction fields, wherein the third orifice and second orifice are aligned along a same axis, the diameter of the third orifice being greater than or equal to the diameter of the second orifice.