CEA, DAM, DIF, Arpajon, France, CEA, LETI, MINATEC Campus, Grenoble, France

This study reports the optimization of the first stages of a MEMS-based, microfabricated time-of-flight mass spectrometer. The authors present an acceptable match between simulations and experimental results. It validates the use of simulations as a time efficient approach as to predict optimal experimental set points. Chips with three differently meshed ionization grids have been tested and show a significant impact of the grid size on both ionization and extraction. An optimal trade-off is found for 3 mm × 3 mm grid, with about 5 × 10?6 ion/atom ionization efficiency and over 50% extraction rate. Optimized parameters for ion focussing are found faster with the help of simulations as the experimental optimal settings are found near the predicted simulated voltages. A total ionic current of hundreds of picoamperes is measured, confirming the potential of this electron-impact ion source as the first step of the full time-of-flight mass spectrometer integrated on a single MEMS chip. © 2016 Elsevier B.V.

Gas analysis, MEMS, Micro mass spectrometer, Simion, Time-of-flight

Economic and social effects, Extraction, Gas fuel analysis, Inductively coupled plasma, Ion sources, Ionization, Ionization of gases, MEMS, Spectrometers, Electron-impact ion sources, Ionization efficiency, Micro mass spectrometer, Optimal setting, Optimized parameter, Simion, Time of flight, Time-of-flight mass spectrometers, Mass spectrometers