title: High sensitivity field asymmetric ion mobility spectrometer.
abstract: A high sensitivity field asymmetric ion mobility spectrometer (FAIMS) was designed, fabricated, and tested. The main components of the system are a 10.6 eV UV photoionization source, an ion filter driven by a high voltage/high frequency n-MOS inverter circuit, and a low noise ion detector. The ion filter electronics are capable to generate square waveforms with peak-to-peak voltages up to 1000 V at frequencies up to 1 MHz with adjustable duty cycles. The ion detector current amplifier has a gain up to 1012V/A with an effective equivalent input noise level down to about 1 fA/Hz1/2during operation with the ion filter at the maximum voltage and frequency. The FAIMS system was characterized by detecting different standard chemical compounds. Additionally, we investigated the use of a synchronous modulation/demodulation technique to improve the signal-to-noise ratio in FAIMS measurements. In particular, we implemented the modulation of the compensation voltage with the synchronous demodulation of the ion current. The analysis of the measurements at low concentration levels led to an extrapolated limit of detection for acetone of 10 ppt with an averaging time of 1 s.
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland.
authors.forename: Mario A
authors.initials: MA
authors.lastname: Chavarria
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland.
authors.forename: Alessandro V
authors.identifier: 0000000187074368
authors.initials: AV
authors.lastname: Matheoud
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland.
authors.forename: Philippe
authors.identifier: 0000000342357510
authors.initials: P
authors.lastname: Marmillod
authors.affiliation: State Key Laboratory of Transducer Technology, Hefei Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, China.
authors.forename: Youjiang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Transducer Technology, Hefei Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, China.
authors.forename: Deyi
authors.initials: D
authors.lastname: Kong
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Brugger
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland.
authors.forename: Giovanni
authors.identifier: 0000000349133114
authors.initials: G
authors.lastname: Boero