INVESTIGATION OF THE BEHAVIOR OF PARTICLES GENERATED FROM A LASER-ABLATED SILICON TARGET USING TIME-OF-FLIGHT MEASUREMENTS

We have investigated the phenomena of ArF-laser ablation with two diff erent time-of-flight techniques and optical emission spectroscopy. The results show that the growth of the plume from the laser-irradiated S i target is divided into two components with fast (15-20 km/s) and slo w (46 m/s) expansion velocities. These two components are created with different thresholds for the laser fluence: 1.8 J/cm2 for the fast co mponent and 2.2 J/cm2 for the slow component. By comparing the results measured with the above three methods and SEM observation, it is thou ght that the origin of the fast component is a hot plasma and that of the slow component includes neutral materials in liquid phase.