Integration of a carbon nanotube field emission electron gun for a miniaturized time-of-flight mass spectrometer Conference

Getty, SA, Li, M, Hess, L et al. (2009). Integration of a carbon nanotube field emission electron gun for a miniaturized time-of-flight mass spectrometer . Proceedings of SPIE - The International Society for Optical Engineering, 7318 10.1117/12.818939

cited authors

  • Getty, SA; Li, M; Hess, L; Costen, N; King, TT; Roman, PA; Brinckerhoff, WB; Mahaffy, PR

abstract

  • A carbon nanotube (CNT) field emission electron gun has been fabricated and assembled as an electron impact ionization source for a miniaturized time-of-flight mass spectrometer (TOF-MS). The cathode consists of a patterned array of CNT towers grown by catalyst-assisted thermal chemical vapor deposition. An extraction grid is precisely integrated in close proximity to the emitter tips (20-35 μm spacing), and an anode is located at the output to monitor the ionization beam current. Ultra-clean MEMS integration techniques were employed in an effort to achieve three improvements, relative to previous embodiments: reduced extraction voltage during operation to be resonant with gas ionization energies, enhanced current transmission through the grid, and a greater understanding of the fundamental current fluctuations due to adsorbate-assisted tunneling. Performance of the CNT electron gun will be reported, and implications for in situ mass spectrometry in planetary science will be discussed. © 2009 SPIE.

authors

publication date

  • September 7, 2009

published in

Digital Object Identifier (DOI)

volume

  • 7318