Optical characterization of thin film laser deposition processes

摘要

Abstract: Pulsed laser deposition (PLD) has recently been shown to be an effective means of depositing thin films from refractory targets. In this study, Nd/YAG and excimer lasers have been used to deposit thin films from refractory, high T$-c$/ superconducting, dielectric, ferroelectric and magnetic targets. Optical emission spectroscopy of the laser induced plume has been used to determine the identity and energy (temperature) of the excited state species present in the laser induced plumes. Temporally and spatially resolved optical emission spectra were obtained using a gated intensified photodiode array detector coupled to a grating spectrometer. The individual emission spectra were analyzed to identify the atomic and ionic species present. The temporal and spatial evolution of individual emission lines were used to determine the velocity of the species in the plume. These results were combined with the results from in situ molecular beam mass spectrometric analysis of the plumes. In addition, studies of the stoichiometry and morphology, as well as the electrical properties, of these PLD thin films were carried out for correlation with the spectroscopic observations.!11