KNaNbO3-LiTaO3-LiSbO3 thin films by pulsed laser deposition

<001> oriented epitaxial thin films of (K,Na)NbO,sub>3-LiTaO
₃
-LiSbO
₃
(KNN-LT-LS) were grown by Pulsed Laser Deposition on <100> single crystal SrTiO
₃
(STO) substrates, which were coated with 200 nm SrRuO
₃
. Experimental data based on X-ray phase analysis and elemental analysis by Rutherford backscattering spectroscopy indicated that deposition under 300 mTorr oxygen partial pressure, and 1.3 J/cm
²
laser fluence were found to be the optimum condition to obtain single phase epitaxial film growth. Furthermore, nanostructural analysis by field emission SEM of films, grown to 400nm thickness at 600-750°C indicated a gradual transition from (001) textured columnar grains to a dense and crack free film. Using XRD ϕ scans, these films were found to be epitaxial with a cube-on-cube relationship with substrate. Dielectric measurements (1 kHz-1 MHz) at room temperature have revealed that the dielectric constant (K) and loss tangent (tanδ) decreased with increasing deposition temperature. Hysteresis loop measurements on 350 nm films showed saturation and spontaneous polarizations of 7.1 and 4 μC/cm
²
; respectively.