D. Romero et Jj. Laserna, MULTIELEMENTAL CHEMICAL IMAGING USING LASER-INDUCED BREAKDOWN SPECTROMETRY, Analytical chemistry, 69(15), 1997, pp. 2871-2876
Multichannel laser-induced breakdown spectrometry (LIES) is used to ge
nerate selective chemical images for sih er, titanium, and carbon from
silicon photovoltaic cells, A 2.5 mi pulsed nitrogen laser and a spec
trometer using charge-coupled device detection were employed. LIBS ima
ges were acquired sequentially by moving the sample located on a motor
ized x-y translational stage step by step while storing the multichann
el LIES spectrum for each position of the sample, followed by computer
-based reconstruction of two-dimensional selective images from intensi
ty profiles at several wave lengths, Depth distributions of carbon imp
urities are also reported, Room temperature and atmospheric pressure o
peration as used here remove the restrictions on sample size exhibited
by other surface analysis techniques used for imaging applications, T
hus, the sample size in LIES imaging is in principle unlimited. A LIES
experiment does not require a sample to be conductive. Therefore, vir
tually all materials can be imaged, Although LIES is a typical example
of destructive analytical technique, multichannel detection as demons
trated here confers the possibility to LIES of obtaining multielement
information from a given surface area, Lateral resolution of 80 mu m a
nd depth resolution of better than 13 nm were observed, The ultimate l
imitation to imaging the first layer of the surface in LIES is the spe
ctral signal-to-noise ratio as dictated by the ablation threshold of t
he material.