A comparative mass spectroscopic study between infrared and ultraviolet laser ablation of a superconducting YBa 2Cu 3O 7− x target

Abstract

Time-of-flight mass spectra of ionic species produced by the laser ablation of a YBa 2Cu 3O 7− x target have been measured. The experimental geometry and laser conditions used in this study are similar to those used for the deposition of thin films by laser ablation. A comparison of the mass spectra by using both an infrared laser and an ultraviolet laser as irradiation sources, provides valuable information regarding the identification of the species responsible for the growth of thin films. In the case of the infrared laser both light- and heavy-mass species are observed. In the case of the ultraviolet laser, only metal ions and their oxides are observed. Oxygen introduced with a pulsed nozzle near the plume enhances the formation of oxides. It is suggested that these oxides provide the means by which the oxygen is transported to the substrate.