Abstract

A 266 nm Nd:YAG laser ablation system equipped with homogenizer optics to convert any type of laser beam profile into a “flat-top” laser profile is described. The influences of the homogenizer arrays on energy distribution across the laser beam and the energy density on the ablation characteristics in relation to signal intensity measured by ICP-MS were investigated. Energy density and related ablation rate for various materials were studied and figures of merit are summarized. It is shown that beam homogenization influences the ablation rate and the ablation characteristics in general. Highly transparent samples, such as quartz, can be ablated at 266 nm Nd:YAG and the homogenized beam leads to less cracking of the material (uncontrolled if insufficiently high energy density is applied to the sample surface). The effect of reduced ablation rate per pulse of a homogenized laser beam in comparison to a Gaussian beam profile has an influence on elemental fractionation, which is shown by the quantification of the well-characterized T1-G glass sample from the MPJ-DING glass series.