US Patent 7872228 Stacked well ion trap

In an apparatus for performing a mass spectrometric analysis of a sample, a plurality of electrodes are positioned and driven by RF potentials to form a plurality of adjacent pseudopotential wells. Ions may be manipulated, reacted, analyzed, and ejected from the apparatus in a manner similar to conventional ion traps. In addition, selected ions or groups of ions may be passed from one pseudopotential well to another pseudopotential well without ion losses due to physical obstructions. The apparatus may be used alone or in conjunction with other mass analyzers to produce mass spectra from analyte ions.