Depth-resolved analysis in multi-layered glass and metal materials using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was examined as a tool for depth analysis in glass and metal samples. Layered experimental samples of known thickness were ablated using 266 nm and 193 n m laser systems. The controlling parameters were power density of the laser , crater geometry and gas medium. Layers at depths of up to 200 mum could b e identified, but accurate determination of the composition of the underlyi ng layer in the material was strongly dependent on the parameters used. Con tinued ablation of material from the upper layer took place for up to 200 l aser pulses after penetrating the underlying layer. Depth resolution was li mited by the mixing of material between shallow and deep levels in the abla tion crater. Optimum conditions were determined for reducing the mixing eff ects and for accurate compositional analysis.