Patent ID: 8859961

Claim:
An ion guide, comprising: a plurality of first electrodes disposed about an axis; a first opening at a first end of the plurality of first electrodes; a second opening at a second end of the plurality of first electrodes; a substrate comprising a plurality of substantially planar second electrodes disposed thereover, the substrate being disposed substantially orthogonally to the axis and comprising a third opening that is substantially aligned with the second opening, wherein the substantially planar second electrodes are substantially circular and substantially concentric, or are substantially parallel to one another and to the substrate; and means for applying a radio frequency (RF) voltage between adjacent pairs of the first electrodes, and between adjacent pairs of the second electrodes, wherein the RF voltage creates an ion confining electrodynamic field in a region between the plurality of first electrodes and the plurality of second electrodes; and means for applying a direct current (DC) voltage drop between the first opening and the second opening.