A Lithographically Patterned Discrete Planar Electrode Linear Ion Trap Mass Spectrometer

• Published in: Journal of microelectromechanical systems 2013-08, Vol.22 (4), p.876-883
• Main Authors: Hansen, Brett J., Niemi, Richard J., Hawkins, Aaron R., Lammert, Stephen A., Austin, Daniel E.
• Format: Article
• Language: English
• Subjects: Applied sciences; Ceramics; Charge carrier processes; Electric potential; Electrodes; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Linear ion trap (LIT); mass spectrometry; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; microfabrication; Micromechanical devices and systems; Physics; Precision engineering, watch making; Radio frequency; Substrates; Surface treatment
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/JMEMS.2013.2248128

We present a linear type radiofrequency ion trap mass spectrometer consisting of metal electrodes that are lithographically patterned onto two opposing planar ceramic substrates. An electric field for ion trapping is formed by applying specific voltage potentials to the electrode pattern. This technique represents a miniaturization approach that is relatively immune to problems with surface roughness, machining complexity, electrode misalignment, and precision of electrode shape. We also present how these traps allow a thorough study of higher order nonlinear effects in the trapping field profile and their effect on mass analyzer performance. This trap has successfully performed mass analysis using both a frequency sweep for resonant ion ejection, and linear voltage amplitude ramp of the trapping field. Better-than-unit mass resolution has been achieved using frequency sweep mass analysis. Mass resolution (m/Δm) has been measured at 160 for peaks of m/z values less than 100.