A microfabrication strategy for cylindrical ion trap mass spectrometer arrays

This paper presents a microfabrication process for the realization of miniature cylindrical ion trap mass spectrometers, based on silicon MEMS technologies. In order to create these traps, several techniques are presented. Porous silicon etching technique resulting in vertical holes has been used to fabricate end-plates. The ring electrode (hole diameter 1.5 mm) has been fabricated using ultrasonic mechanical drill technique. Deep reactive ion etching (DRIE) was also used for fabrication of both ring electrode arrays and end-plate holes. The surfaces of the ring electrode and the end-plates have been made conducting by n+ doping. CYTOP films have been used both as a bonding layer and an insulator to bond the ring electrode to end-plates while ensuring electrical isolation. The thickness of CYTOP films has been chosen to ensure that it can withstand voltages up to 200 V while maintaining its bond strength.