Elemental Fractionation Studies of 193 nm ArF Excimer Laser Ablation System at High Spatial Resolution Mode

The limit of detection (LOD), ICP mass load effect, downhole induced fractionation and matrix effect of 193 nm ArF excimer laser ablation system at high spatial resolution were systematically investigated. Trace elements in GSD-1G, StHs6/ 80-G and NIST612 were measured at 10 mu m spot size. The results showed that the LOD decreased with the increasing ablation diameter. In addition, the LOD of part of trace elements was in a range of 1-10 mu g g(-1) at 7 mu m spot size. Mass load effect was negatively correlated with the corresponding oxide melting temperature, while positively correlated with the elemental 1st ionization potential. Downhole fractionation was negligible when the ratio of ablation depth to spot size was smaller than 1: 1. Matrix effect between NIST610, GSD-1G, ATHO-G and StHs6/80-G did not change in the spot size ranged from 10 mu m to 50 mu m. The analytical results of GSD-1G, StHs6/80-G and NIST612 at 10 mu m spot size matched well with the reference values. Generally, 10 mu m spatial resolution could satisfy the requirements of trace elements analysis.