title: Wavelength Scanning with a Tilting Interference Filter for Glow-Discharge Elemental Imaging.
abstract: Glow discharges have long been used for depth profiling and bulk analysis of solid samples. In addition, over the past decade, several methods of obtaining lateral surface elemental distributions have been introduced, each with its own strengths and weaknesses. Challenges for each of these techniques are acceptable optical throughput and added instrumental complexity. Here, these problems are addressed with a tilting-filter instrument. A pulsed glow discharge is coupled to an optical system comprising an adjustable-angle tilting filter, collimating and imaging lenses, and a gated, intensified charge-coupled device (CCD) camera, which together provide surface elemental mapping of solid samples. The tilting-filter spectrometer is instrumentally simpler, produces less image distortion, and achieves higher optical throughput than a monochromator-based instrument, but has a much more limited tunable spectral range and poorer spectral resolution. As a result, the tilting-filter spectrometer is limited to single-element or two-element determinations, and only when the target spectral lines fall within an appropriate spectral range and can be spectrally discerned. Spectral interferences that result from heterogeneous impurities can be flagged and overcome by observing the spatially resolved signal response across the available tunable spectral range. The instrument has been characterized and evaluated for the spatially resolved analysis of glow-discharge emission from selected but representative samples.
authors.affiliation: 1 Department of Chemistry, Indiana University, Bloomington, IN, USA.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Storey
authors.affiliation: 1 Department of Chemistry, Indiana University, Bloomington, IN, USA.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Ray
authors.affiliation: 2 IFW Dresden e.V., Leibniz Institute for Solid State and Materials Research Dresden, Dresden, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Hoffmann
authors.affiliation: 2 IFW Dresden e.V., Leibniz Institute for Solid State and Materials Research Dresden, Dresden, Germany.
authors.forename: Maxim
authors.initials: M
authors.lastname: Voronov
authors.affiliation: 1 Department of Chemistry, Indiana University, Bloomington, IN, USA.|3 Department of Chemistry and Biology, University of Siegen, Siegen, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Engelhard
authors.affiliation: 4 Department of Inorganic and Analytical Chemistry, University of Münster, Münster, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Buscher
authors.affiliation: 1 Department of Chemistry, Indiana University, Bloomington, IN, USA.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Hieftje
keywords: Glow discharge; atomic emission spectrometry; elemental mapping; off-normal interference filter; spectral interference