Crystalline properties of strontium barium niobate thin films produced by pulsed-laser deposition

Highly oriented strontium barium niobate (SBN) thin films have been grown o n MgO{100} substrates by pulsed-laser deposition. The films have been chara cterized by X-ray diffraction (XRD), scanning electron microscopy and atomi c force microscopy. XRD theta-2 theta scans indicate single-phase crystalli ne SBN layers with the {100} orientation perpendicular to the plane of the substrate. Because of the difference between the thermal expansion coeffici ents of the SBN thin film and the MgO{100} substrate, it is necessary to ad opt a slow cooling rate after deposition to retain the highly oriented SBN thin film on the substrate. The presence of non-uniform residual strain in SBN thin films has been analysed from the broadening of the (00l) SBN film diffraction lines. The influence of oxygen partial pressure on the crystall ine properties of SBN thin films has also been investigated.