氧压对SrTiO3和SrNb0.2Ti0.8O3薄膜晶格参数的影响及激光感生热电电压效应

采用脉冲激光沉积技术制备了SrTiO₃和SrNb_0.2Ti_0.8O₃薄膜.X射线衍射分析表明在LaAlO₃(100)单晶平衬底上生长的SrTiO₃及SrNb_0.2Ti_0.8O₃薄膜是沿［001］取向的近外延生长.随着氧压在一定范围内逐渐增大，SrTiO₃薄膜的晶格参数减小，而SrNb_0.2Ti_0.8O₃薄膜的晶格参数先减小后增大.同时摸索出制备具有二维电子气超晶格(SrTiO₃/SrNb_0.2Ti_0.8O₃)_L的最佳氧压为1.0×10^-2Pa.另外在LaAlO₃(100)倾斜衬底上制备的SrNb_0.2Ti_0.8O₃薄膜中观察到激光感生热电电压效应. 关键词： 0.2Ti_0.8O₃薄膜')" href="#">SrNb_0.2Ti_0.8O₃薄膜 晶格参数 激光感生热电电压 脉冲激光沉积

Oxygen pressure effect on lattice parameters of SrTiO3 and SrNb0.2Ti0.8O3 thin films and laser-induced thermoelectric voltages effect

SrTiO₃ and SrNb_0.2Ti_0.8O₃ thin films were prepared by pulsed laser deposition technique on LaAlO₃ (100) single crystal substrates. X-ray diffraction shows that all the thin films have［001］ orientation. With the oxygen pressure increasing, the lattice parameter c of SrTiO₃ thin films decreases, while the lattice parameter c of SrNb_0.2Ti_0.8O₃ thin films decreases and then increases. Meanwhile, the optimal oxygen pressure to prepare (SrTiO₃/SrNb_0.2Ti_0.8O₃)_L multilayer of two-dimensional electron gas was found to be 1.0×10^-2Pa. In addition, laser-induced thermoelectric voltage effect was observed on SrNb_0.2Ti_0.8O₃ thin film prepared on vicinal-cut LaAlO₃ (100) substrate for the first time.