%0 Journal Article
%K Ablation
%K Laser
%K Laser ablation
%K Laser ablation
%K Vaporization
%K Plasma
%K Nanosecond
%K Nanosecond laser
%K Plasma shielding
%K Preferential vaporization
%A Xianglei Mao
%A Wing-Tat Chan
%A Manuel Caetano
%A Mark A Shannon
%A Richard E Russo
%B Applied Surface Science
%D 1996
%F Laser
%G eng
%P 126-130
%R 10.1016/0169-4332(95)00420-3
%T Preferential vaporization and plasma shielding during nano-second laser ablation
%V 96-98
%8 04/1996
%X <p>Preferential removal of components from mixed material targets and plasma shielding are studied by using inductively coupled plasma-atomic emission spectrometry (ICP-AES) during UV nano-second laser ablation. The ICP emission intensity for Cu and Zn during ablation of brass samples varies versus laser power density. A model using thermal evaporation and inverse Bremsstrahlung processes is presented. The model shows that plasma shielding occurs at approximately 0.3 GW/cm<sup>2</sup>, in agreement with experimental data for change in the mass ablation rate. The good agreement of model and experimental data suggest that thermal effects are important during nano-second laser ablation for power density less than 0.3 GW/cm<sup>2</sup>.</p>