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采用脉冲激光沉积(PLD)技术,经一系列的优化实验成功地制备了BaTiO3(BT)和Ba0.6Sr0.4TiO3(BST)单层膜.X射线衍射分析表明,在LaAlO3(001)单晶平衬底上生长的BT和BST薄膜都是沿[001]取向的近外延生长.且随着氧压在10-3—25Pa范围内逐渐增大,BST薄膜的晶格常数与氧压之间近似满足Boltzmann函数关系.其次,在此优化条件下还制备出了高质量的BT/BST超晶格,AFM测量表明BT/BST超晶格的最大均方根粗糙度仅为0.3048nm,薄膜表面达到了原子尺度的光滑.另外,在超晶格的XRD图谱中还清楚地观察到了卫星峰,根据(002)衍射峰周期调制的卫星峰计算了超周期,得到了BT和BST薄膜的沉积速率.最后,在倾斜单晶衬底上制备的BT/BST超晶格中还首次发现了在BT和BST单层膜中都没有发现的激光感生热电电压(LITV)效应.
BaTiO3 (BT) and Ba0.6Sr0.4TiO3 (BST) monolayers were successfully prepared by a series of optimization experiments using pulsed laser deposition (PLD) technique. X-ray diffraction analysis showed that in the LaAlO3 (001) Both BT and BST films grown on the substrate are near-epitaxial growth along the [001] orientation, and as the oxygen pressure gradually increases in the range of 10-3-25 Pa, the lattice constant of the BST film is approximately the same as the oxygen pressure And satisfy the Boltzmann function relationship.Secondly, high quality BT / BST superlattices were also prepared under the optimal conditions. AFM measurements showed that the maximum root mean square roughness of BT / BST superlattices was only 0.3048nm, In addition, the satellite peaks were clearly observed in the XRD patterns of superlattices, and the hypersurfaces were calculated from satellite peaks modulated periodically by the (002) diffraction peak, and the deposition rates of BT and BST films were obtained. Finally, the laser-induced thermoelectric voltage (LITV) effect not found in BT and BST monolayers was first found in BT / BST superlattices prepared on sloping single crystal substrates.