Simulation of Unidirectional Ion Ejection in Miniature Four-Channel Linear Ion Trap Array.

With the surging demand for dynamic, real-time, and rapid qualitative analysis of chemical components, chip-scale mass spectrometers have attracted widespread attention. Ion traps have become the preferred mass analyzer for chip-scale mass spectrometers due to their excellent analytical performance. However, the miniaturization of ion traps inevitably leads to a reduction in ion storage capacity, which in turn affects their sensitivity and dynamic range. In this study, a Miniature Four-Channel Linear Ion Trap Array (M-FLITA) with hyperbolic electrodes and a 1 mm field radius was established and optimized. Concurrently, unidirectional ion ejection was accomplished by the application of asymmetric RF voltages on M-FLITA. The results demonstrate that, in the stretched structure, the mass resolution is improved to 732, while the unidirectional ion ejection efficiency is maintained at 96%. M-FLITA demonstrates advantages in terms of high ion storage capacity and mass resolution under high ion flux conditions, providing an ideal solution for high-performance micro mass analyzers in chip-scale mass spectrometers.