Effect of excess Pb on epitaxial growth of Pb(Mg1/3Nb2/3)O3 thin films prepared by chemical solution deposition process

• Published in: Journal of the Ceramic Society of Japan 2013/08/01, Vol.121(1416), pp.638-643
• Main Authors: KIGUCHI, Takanori, TSUKAMOTO, Tomohito, FAN, Cangyu, NISHIJIMA, Masahiko, KONNO, Toyohiko J.
• Format: Article
• Language: English
• Subjects: Crystallinity; Excess PbO; MOD; Morphology; Pb(Mg1/3Nb2/3)O3; Post-annealing; Thin film; Transmission electron microscopy
• ISSN: 1882-0743; 1348-6535
• DOI: 10.2109/jcersj2.121.638

This study investigated the effect of excess PbO and post-annealing on the crystallinity and the microstructure of Pb(Mg1/3Nb2/3)O3 (PMN) epitaxial thin films. PMN thin films were deposited on SrTiO3 (STO) (001) substrates using a chemical solution deposition (CSD) process with rapid thermal annealing (RTA) of spin-coated metallo-organic decomposition (MOD) solutions. The nominal film composition was Pbx(Mg1/3Nb2/3)O3 (x = 1.0 or 1.1). All films showed the (001)PMN//(001)STO, [001]PMN//[001]STO epitaxial relationship and were single phase perovskite PMN without any pyrochlore phases. The Pb1.1(Mg1/3Nb2/3)O3/SrTiO3 thin film post-annealed at 973 K with facing treatment showed the highest crystallinity of 0.8° in full width at half maximum (FWHM) of the 002PMN rocking curve. Transmission electron microscopy (TEM) revealed PbO nanoparticles on the surface of the PMN thin films. The film composition was almost stoichiometric. On the other hand, the Pb1.1(Mg1/3Nb2/3)O3/SrTiO3 thin film post-annealed at 973 K without facing treatment showed crystallinity of 1.0° and no PbO nanoparticles. The film composition was almost stoichiometric. These results indicate that the excess PbO is not incorporated into the PMN films. Instead, it volatizes from the film surface, which improves the crystallinity and inhibits the PMN decomposition.