Observation of the behavior of a laser-ablated plume by laser imaging spectroscopic techniques

Abstract

In order to investigate the behavior of species in the laser-ablation plume during the pulsed-laser deposition (PLD) process, the time-resolved two-dimensional laser-induced fluorescence spectroscopy (2D-LIF) and Rayleigh-Mie scattering (2D-RMS) systems have been developed. Results on PLD of high-temperature superconducting thin films of YBa2Cu3O7-x (YBCO) are presented. First, the effects of Doppler and collisional quenching on the sensitivity of 2D-LIF are examined. Then the spatial distributions of the ground state Cu atoms observed by these techniques, as well as excited particles in the laser ablation process of YBCO, are presented. The effect of substrate heating on plume propagation has been observed for the first time. 2D-RMS was applied to visualize the behavior of particles directly ejected from the target and of particles condensed in the gas phase.