STOICHIOMETRIC TRANSFER OF COMPLEX OXIDES BY PULSED-LASER DEPOSITION

Citation
B. Dam et al., STOICHIOMETRIC TRANSFER OF COMPLEX OXIDES BY PULSED-LASER DEPOSITION, Applied surface science, 96-8, 1996, pp. 679-684
Citations number
16
Categorie Soggetti
Physics, Condensed Matter","Chemistry Physical","Materials Science, Coatings & Films
Journal title
ISSN journal
01694332
Volume
96-8
Year of publication
1996
Pages
679 - 684
Database
ISI
SICI code
0169-4332(1996)96-8:<679:STOCOB>2.0.ZU;2-M
Abstract
The interaction of a spatially uniform 248 nm excimer laser beam with targets of various oxides (Ya(2)Cu(3)O(7-delta), Y2BaCuO5, Y2O3 and Sr TiO3) is investigated. We identify two different mechanisms for non-st oichiometric ablation. Evidence is found that in YBa2Cu3O7-delta and Y 2BaCuO5 the non-stoichiometric ablation at low fluences is due to a ph ase transformation of the target surface. This is a gradual process, o nly observable after prolonged irradiation of the target, For congruen tly melting SrTiO3 such a phase transformation is neither expected nor observed. We find, however, that at low fluences within 100 laser sho ts the target surface composition equilibrates to a stable, Ti-rich co mposition, In this case, the mechanism we propose is preferential abla tion, which is accompanied by bulk diffusion to compensate the induced surface depletion.