沉积温度对LaNiO_3薄膜结构和性能的影响

Impacts of Deposition Temperature on the Structural and Physical Properties of LaNiO_3 Films

采用磁控溅射法在（001）SrTiO3基片上制备了LaNiO3氧化物薄膜，应用X射线衍射（XRD）、反射式高能电子衍射（RHEED）、原子力显微镜（AFM）、四探针测试仪等技术系统研究了沉积温度对LaNiO3薄膜结构和性能的影响。结果表明在较低的生长温度和较宽的温度范围内（250-400℃）都能得到外延LaNiO3薄膜。输运性质的测量结果表明在其它条件不变的情况下，250℃温度下生长的LaNiO3薄膜具有最高的电导率。

LaNiO3 film has been received much attention in the ferroelectric community to be used as electrode/buffer layer in ferroelectric applications. Epitaxial LaNiO3 films were prepared on （001） SrTiO3 substrates at various temperatures. Techniques such as X-ray diffraction （ XRD）, reflection high energy electron diffraction （RHEED）, atomic force microscope （AFM） and four-probe measurement were used to characterize the impacts of deposition temperature on the structural and physical properties of LaNiO3 films. It is shown that epitaxial LaNiO3 films can be prepared at a very low temperature （ 250% ） and a wide temperature range. Both the grain size and root mean square roughness （ RMS ） of LaNiO3 films increase with increasing deposition temperature. RHEED images of LaNiO3 films deposited at temperatures from 250℃ to 400℃ demonstrate very good RHEED patterns, which indicate that LaNiO3 films could be prepared at the very wide temperature range. The resistivity of LaNiO3 film decreases with increasing deposition temperature below 250℃, and increases very slowly with increasing temperature over 250℃. This work may pave a way to study influence of the deposition temperature of LaNiO3 films used as electrodes of ferroelectric memories on properties of ferroelectric domains and structure etc.