Title :
A Micro Ionizer for Portable Mass Spectrometers using Double-gated Isolated Vertically Aligned Carbon Nanofiber Arrays
Author :
Chen, L.-Y. ; Velásquez-García, L.F. ; Wang, X. ; Teo, K. ; Akinwande, A.I.
Author_Institution :
Massachusetts Inst. of Technol., Cambridge
Abstract :
We report micro-fabricated double-gated vertically aligned carbon nanofiber (CNF) arrays for ionization of gasses in low power portable mass spectrometers. The devices can be operated in one of two modes - electron impact ionization (EII ) or field ionization (FI). When operated as electron impact ionizer, power dissipation was reduced from >1 W typical of thermionic emission based electron impact ionizers to <100 mW. When operated as a field ionizer, the turn-on voltage for field ionization is reduced from 5-10 kV typical of ungated ionizers to 350 V.
Keywords :
arrays; carbon fibres; electron impact ionisation; field ionisation; mass spectrometer accessories; mass spectrometers; micromachining; micromechanical devices; nanostructured materials; thermionic emission; double-gated isolated vertically aligned carbon nanofiber arrays; electron impact ionization mode; field ionization mode; gas ionization; low power portable mass spectrometers; microionizer; power dissipation; thermionic emission; Chemical vapor deposition; Electrodes; Electron emission; Electrostatics; Ionization; Isolation technology; Mass spectroscopy; Plasma chemistry; Thermionic emission; Voltage;
Conference_Titel :
Electron Devices Meeting, 2007. IEDM 2007. IEEE International
Conference_Location :
Washington, DC
Print_ISBN :
978-1-4244-1507-6
Electronic_ISBN :
978-1-4244-1508-3
DOI :
10.1109/IEDM.2007.4419080
