Pulsed r.f.-glow-discharge time-of-flight mass spectrometry for fast surface and interface analysis of conductive and non-conductive materials

Glow discharge (GD) is a highly specialised source that especially meets the requirements for accuracy, simplicity and speed for content depth profiling and bulk analysis in both optical emission (OES) and mass spectrometry (MS). The pulsed radio frequency GD source has the potential for both elemental and molecular analysis of conductive and non-conductive materials. To exploit the information delivered by pulsed radio frequency (r.f.)-GD sources, fast sampling is required, and is available only through time-of-flight mass spectrometry (ToF-MS). Compared to optical glow discharge (GD-OES) instrumentation, a GD-ToF-MS system shows much simpler spectra, lower background signals and lower detection limits. The presented new r.f.-GD-ToF-MS system is a successful combination of a commercial high-end glow discharge instrument and an extremely fast and high-resolution time-of-flight mass spectrometer. This new instrument was applied to analyse conductive and non-conductive materials like anodic thin films. We could resolve 2-nm Cr makers in aluminium oxide layers and measure trace elements in ultra thin titanium oxide films. Furthermore, we show the potential of the pulsed mode to separate analyte species from elements originating from residual gas. Copyright (C) 2006 John Wiley & Sons, Ltd.