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Title: Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures

Abstract

A simple method is described for the unambiguous identification of the individual components in a gas mixture showing strong overlapping of their mass spectrometric cracking patterns. The method, herein referred to as cryotrapping assisted mass spectrometry, takes advantage of the different vapor pressure values of the individual components at low temperature (78 K for liquid nitrogen traps), and thus of the different depletion efficiencies and outgassing patterns during the fast cooling and slow warming up of the trap, respectively. Examples of the use of this technique for gas mixtures with application to plasma enhanced chemical vapor deposition of carbon and carbon-nitrogen hard films are shown. Detection of traces of specific C{sub 3} hydrocarbons (<50 ppm of initial methane) in methane/hydrogen plasmas and the possible trapping of thermally unstable C-N compounds in N{sub 2} containing deposition plasmas are addressed as representative examples of specific applications of the technique.

Authors:
;  [1]
  1. Laboratorio Nacional de Fusion por Confinamiento Magnetico, CIEMAT, Avda Complutense 22, Madrid 28040 (Spain)
Publication Date:
OSTI Identifier:
20979382
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films; Journal Volume: 25; Journal Issue: 2; Other Information: DOI: 10.1116/1.2432351; (c) 2007 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARBON; CHEMICAL VAPOR DEPOSITION; CRACKING; DEGASSING; HYDROGEN; MASS SPECTROSCOPY; METHANE; MIXTURES; NITROGEN; PLASMA; TEMPERATURE RANGE 0065-0273 K; VAPOR PRESSURE

Citation Formats

Ferreira, Jose A., and Tabares, Francisco L. Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures. United States: N. p., 2007. Web. doi:10.1116/1.2432351.
Ferreira, Jose A., & Tabares, Francisco L. Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures. United States. doi:10.1116/1.2432351.
Ferreira, Jose A., and Tabares, Francisco L. Thu . "Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures". United States. doi:10.1116/1.2432351.
@article{osti_20979382,
title = {Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures},
author = {Ferreira, Jose A. and Tabares, Francisco L.},
abstractNote = {A simple method is described for the unambiguous identification of the individual components in a gas mixture showing strong overlapping of their mass spectrometric cracking patterns. The method, herein referred to as cryotrapping assisted mass spectrometry, takes advantage of the different vapor pressure values of the individual components at low temperature (78 K for liquid nitrogen traps), and thus of the different depletion efficiencies and outgassing patterns during the fast cooling and slow warming up of the trap, respectively. Examples of the use of this technique for gas mixtures with application to plasma enhanced chemical vapor deposition of carbon and carbon-nitrogen hard films are shown. Detection of traces of specific C{sub 3} hydrocarbons (<50 ppm of initial methane) in methane/hydrogen plasmas and the possible trapping of thermally unstable C-N compounds in N{sub 2} containing deposition plasmas are addressed as representative examples of specific applications of the technique.},
doi = {10.1116/1.2432351},
journal = {Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films},
number = 2,
volume = 25,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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