Metastable transfer emission spectroscopy—method and instrument for detection and measurement of trace materials in gas flows

Abstract

A simple and relatively inexpensive new technique for qualitatively and quantitatively measuring various gas-phase species in a flow and the apparatus for implementation are described. Detection of atomic species has been demonstrated from concentrations greater than 10(10) atoms/cm(3) to approximately 10(4) atoms/cm(3). Several classes of molecules can also be detected quatitatively with the method, although with somewhat reduced sensitivity. The method, metastable transfer emission spectroscopy (MTES), is particularly useful in materials analysis. Possible applications including the analysis of gas, liquid, and solid samples and the determination of vapor-pressure curves are discussed.

Determination of carbon in trichlorosilane by metastable transfer emission spectrometry

“…The apparatus developed for this technique was derived from that of Capelle and Sutton (8)(9)(10)(11) and is, in most respects, a routine microwave discharge apparatus. Minor modifications were made to accommodate the highly reactive TCS sample and to ensure reproducible discharge conditions.…”

Surface-hopping model for near-resonant electronic energy transfer

“…Transfer reactions, e.g., Reaction (1), are the basis for the recently developed metastable transfer emission spectroscopy technique, 2 which is a powerful method for determining trace components in gas mixtures. optimize the performance of this system and analogous potential laser systems, it is necessary to be able to model the dependence of the key transfer step, Reaction (2), on such parameters as energy defect, reactant states, and gas temperature.…”

Atmospheric pressure active nitrogen (APAN) - a new source for analytical emission spectroscopy

“…that a low pressure active nitrogen afterglow could be utilized as an excitation source for analytical spectroscopy (34)(35)(36)(37)(38). Detection of gas phase Bi and GeH^ down to 10^ atoms/cm^ and 10^ molecules/cm^, respectively, was demonstrated (34)(35)(36), The proposed mechanism of excitation involved energy transfer from metastable, active-nitrogen species generated in a microwave cavity. More recently, the same system has been evaluated as a selective detector for gas chromatography (37,38).…”