• Epitaxial ${\mathrm{Pb(Mg}}_{\text{1/3}}{\mathrm{Nb}}_{\text{2/3}}){\mathrm{O}}_3$ thin films synthesized by metal-organic chemical vapor deposition

Metal-organic chemical vapor deposition was used to prepare ${\mathrm{Pb(Mg}}_{\mathrm{1/3}}{\mathrm{Nb}}_{\mathrm{2/3}}{\mathrm{)O}}_3$ (PMN) thin films on (001) ${\mathrm{SrTiO}}_3$ and ${\mathrm{SrRuO}}_{\mathrm{3}}{\mathrm{/SrTiO}}_3$ substrates, using solid Mg β-diketonate as the Mg precursor. Parameters including the precursor ratio in the vapor phase, growth temperature, growth rate, and reaction pressure in the reactor chamber were varied in order to determine suitable growth conditions for producing phase-pure, epitaxial PMN films. A cube-on-cube orientation relationship between the thin film and the ${\mathrm{SrTiO}}_3$ substrate was found, with a (001) rocking curve width of 0.1°, and in-plane rocking-curve width of 0.8°. The root-mean-square surface roughness of a 200-nm-thick film on ${\mathrm{SrTiO}}_3$ was 2 to 3 nm as measured by scanning probe microscopy. The zero-bias dielectric constant and loss measured at room temperature and 10 kHz for a 200-nm-thick film on ${\mathrm{SrRuO}}_{\mathrm{3}}{\mathrm{/SrTiO}}_3$ were approximately 1100 and 2%, respectively. The remnant polarization for this film was 16 $\mu {\mathrm{C/cm}}^2.$