Chemical maps of patterned samples by microline-imaging laser-induced plasma spectrometry

The potential of a microline-imaging laser-induced plasma spectrometry (LIPS) system for surface and depth analysis of heterogeneous solid samples in air at atmospheric pressure has been demonstrated. A pulsed Nd:YAG laser beam operating at 532 nm, with a homogeneous energy distribution (flat top laser), was used to generate a microline plasma on the sample surface. Subsequent light from the microline plasma was resolved spectrally and spatially and detected with an imaging spectrograph and an intensified charged-coupled device detector. A patterned metal sample was chosen as the most appropriate for this study. Three-dimensional chemical maps of Ni and Cu from the edge connectors of a printed circuit board have been obtained. With this experimental configuration, the lateral resolution (limited by crater width) was 42 mum and the spatial resolution along the spectrometer slit was 17.4 mum. The results illustrate the capability of microline imaging for fast mapping of large-area samples and for depth profiling purposes. Copyright (C) 2003 John Wiley Sons, Ltd.