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. © 1998 Scripta Technica, Electr Eng Jpn, 124(4): 18–26, 1998

Characteristics of Optical Emission Spectra Induced by Laser Beams and Crystallization of PBZNZT Thin Films

“…Figure 2c). [14] When P O 2 is increased from 0.50 to 1.0 mbar, T p is decreased from 5798 to 4041 K, indicating that the kinetic energy of the laser-ejected species is lowered significantly when P O 2 > 0.55 mbar. Therefore, the possible explanation for the degraded P-E properties for P O 2 > 0.55 mbar case is that the laser-ejected species might possess insufficient kinetic energy to crystallize completely.…”

Substrate heating effects on the propagation dynamics of laser produced plume during pulsed laser deposition of oxides

“…The different studies carried out so far have considered primarily the expansion dynamics of the ablated plume in a background gas addressing the influence of the ambient pressure and composition on the characteristics of the precursor species reaching the substrate [3][4][5][6]. Instead, the effect of the substrate temperature on the plume dynamics has been only scarcely considered [7,8]. Geohegan et al [7] analyzed the influence of a heated substrate on nanoparticles formation and transport, while Nakata et al [8] only qualitatively addressed the experimental observation of a reduced resistance encountered by the expanding plume during its propagation through the background gas.…”

“…Instead, the effect of the substrate temperature on the plume dynamics has been only scarcely considered [7,8]. Geohegan et al [7] analyzed the influence of a heated substrate on nanoparticles formation and transport, while Nakata et al [8] only qualitatively addressed the experimental observation of a reduced resistance encountered by the expanding plume during its propagation through the background gas. Therefore, to our knowledge, there is no specific study which reports a direct analysis of the substrate temperature on the plume propagation in a background gas.…”

Infrared laser ablation dynamics using light scattering

“…Light scattering fast photography uses two pulsed lasers: the first laser irradiates the sample target to create a plume of material and the second laser is used as a strobe light to illuminate material in the expanding plume which is imaged using a high speed camera [45,46]. Because this method relies on Mie scattering, it is most sensitive to the particulate component of the plume [47,48]. With the interference approaches, the plume is irradiated from behind by the pulsed light source which is focused into the camera.…”