Electronic probe measurements of pulsed copper ablation at 248 nm

We have used a single wire probe to measure time of flight velocities for copper photoablated with a 248 nm pulsed excimer laser. For the range of fluences, 1.6-12 J/cm2, we find copper ion velocities in the range of 1-2×106 cm/s. We have used Langmuir probe theory to determine ion densities and electron temperatures as a function of fluence and target-probe separation. Results are consistent with recent kinetic and photoablated plasma theories.