Patent ID: 9536722
Date: 2017-01-03
CPC Classifications: H01J,H05K

Claim:
1. An ion guide for mass spectrometry comprising an electrode arrangement of at least two electrodes, at least one of which is an RF electrode, arranged adjacent to each other but spaced apart on a planar surface of a dielectric material, wherein the arrangement has been produced by separately providing the dielectric material and arranging the electrodes on it in a subsequent step, and wherein the electrodes are arranged at a distance from an ion flow path, wherein a portion of the dielectric surface is exposed between an adjacent pair of the spaced apart electrodes and wherein at least one electrode of said adjacent pair of electrodes is arranged to overhang the exposed portion of surface between them such that there is no direct line of sight from the ion flow path to the exposed portion of dielectric surface, ion-facing surfaces of said adjacent pair of electrodes are at different distances from the surface of the dielectric material and the electrode of the pair with the surface at a greater distance from the dielectric surface overhangs the exposed portion of dielectric surface and at least a part of the other electrode of the pair.