Formation and Expansion of Ablation Plasmas Produced by Pulsed Ion Beams for Thin Films Production

The formation and expansion of the ablation plasmas by ion-beam evaporation (IBE), which was a method of the thin films production using the ablation plasmas deposited on the substrates, were analyzed numerically. We used the one-dimensional hydrodynamic model explained the interaction between the targets and incident ion beams. Changing ion beam angle could control the ablation pressure during the formation of the ablation plasma without significantly changes of the plasma temperature. The expansion velocities of the ablation plasma reached up to the substrates for various target materials were defined by distributions of the ion number densities of the ablation plasmas, and were agreed well with experimental ones observed by high-speed camera. We found out that there was a time lag of the ablation plasma reached up to the substrate between the peak of the plasma ion number density and plasma temperature. The numerical results of the expansion velocities of the ablation plasmas and plasma temperatures could apply to estimate for the production of not only the thin films but also the multi-layered ones.