Concept and simulation of a MEMS cycloidal mass analyzer

This study investigates the miniaturization pathway of cycloidal mass spectrometry, a technique distinguished by its inherent perfect-focusing properties, and introduces a planar, stacked-layer MEMS-based cycloidal mass analyzer. A comprehensive numerical analysis was conducted to elucidate the effects of key design parameters, namely electric sector geometry, electrode geometry, and operating vacuum, on ion focusing and mass separation performance. The results indicate that appropriate optimization of geometric dimensions and electrode arrangement density effectively mitigates electric field distortion, thereby improving ion beam focusing and resolution. Configured with an electric sector size of 32.60 mm × 41.10 mm × 6.85 mm and 83 electrode pairs, and operated under a vacuum of 1 × 10^-3 Pa, the device achieves full width at half maximum (FWHM) values of approximately 0.03 Da for light ions (H₂⁺, He⁺) and about 0.40 Da for heavier ions (Ar⁺, CO₂⁺). Across the m/z range of 2-50 Da, the analyzer maintains a resolution greater than 99 and an ion detection efficiency exceeding 92%, demonstrating robust separation and transmission performance over a wide mass-to-charge range.