ND-YAG LASER IRRADIATION OF MOLECULAR-BEAM-EPITAXY-DEPOSITED YBA2CU3O7-X SUPERCONDUCTING THIN-FILMS

Superconducting thin films of 123 compound were deposited on (100) sin gle-crystalline SrTiO3 substrates using a molecular-beam-epitaxy syste m. Films were characterized by x-ray diffraction, scanning electron mi croscopy and compositional analysis using the EDAX technique. The film s were irradiated by a 1.064 mu m wavelength Q-switched Nd:YAG; laser of 20 ns pulse duration at 1.0 J cm(-2)/shot energy density. A systema tic comparison of the film microstructure and compositional analysis b efore and after irradiation is presented here. Theoretical calculation s based on a thermal model of laser heating to determine the surface-t emperature rise of the film were performed using the finite-difference method. The film microstructure, showing fusion of grains, is attribu ted to the bolometric response of the whole film during 1.064 mu m las er irradiation.