Two-dimensional mapping of elements on surfaces using line spark laser-induced breakdown spectroscopy

Abstract

Typically, investigation of the spatial distribution of elements on surfaces using laser-induced breakdown spectroscopy (LIBS) has been carried out by focusing a large number of laser pulses as a closely-spaced series of spots on the sample surface. The small size of each spot (to obtain a spatially-resolved map) requires a large number of independent measurements. Using a line spark (1-1.5 cm long at ca. 100 mJ), however, and imagining the spark as a line on a spectrograph slit, a large area can be interrogated in a short time. We have used this method to rapidly scan the surfaces of metals for contaminants and rock faces to determine the distribution of elements.Typically, investigation of the spatial distribution of elements on surfaces using laser-induced breakdown spectroscopy (LIBS) has been carried out by focusing a large number of laser pulses as a closely-spaced series of spots on the sample surface. The small size of each spot (to obtain a spatially-resolved map) requires a large number of independent measurements. Using a line spark (1-1.5 cm long at ca. 100 mJ), however, and imagining the spark as a line on a spectrograph slit, a large area can be interrogated in a short time. We have used this method to rapidly scan the surfaces of metals for contaminants and rock faces to determine the distribution of elements.