Kf. Willey et al., Routine analysis at sub-micron resolution through the use of sputtered initiated resonance ionization spectroscopy, APPL SURF S, 145, 1999, pp. 36-40
Imaging at sub-micron lateral resolution is now possible due to the advent
of liquid metal ion gun (LMIG) sources. The cost, however, is a reduction i
n ion beam current at the surface, which directly affects the number of des
orbed particles available for analysis. Furthermore, as the needs grow for
chemical imaging at increasingly smaller areas, the demands on the detectio
n step become enormous. Sputter initiated resonance ionization spectroscopy
(SIRIS) offers advantages over conventional techniques. In SIRIS, desorbed
neutral particles are photoionized through resonance excitation steps and
then mass analyzed. This process nearly eliminates matrix effects and mass
interferences, two problems that plague conventional SIMS (secondary ion ma
ss spectrometry). Moreover, analysis of desorbed neutrals, rather than seco
ndary ions, generally increase the detection efficiency by at least two ord
ers of magnitude. Here we present data that demonstrates the ability of SIR
IS to produce depth profiles over a large dynamic range and high lateral re
solution images of Cu contaminant in a CdZnTe film. (C) 1999 Elsevier Scien
ce B.V. All rights reserved.