摘要
透明导电氧化物薄膜在光伏器件、平面显示器件中有着广泛的应用,其介电函数是薄膜材料器件化过程中不可忽略的基本物理参数。使用脉冲激光沉积技术,在(LaAlO3)0.3(Sr2AlTaO6)0.35(LSAT)基底上成功制备了La2/3Sr1/3VO3(LSVO)薄膜,并运用光谱椭偏仪测量了LSVO薄膜的椭偏光谱。先后用B样条模型和Lorentz+Tauc-Lorentz联合色散模型描述了材料的介电函数,并首次具体给出了LSVO薄膜的介电函数。结果表明,LSVO薄膜在1.24~5.06 eV光谱范围内存在3.41 eV和4.11 eV两个明显的光学跃迁,其中3.41 eV的跃迁峰为材料的光学带隙,与未掺杂的LaVO3材料相比,有着0.19 eV的红移;高能区域的4.11 eV的跃迁峰则源自于O 2p轨道和空置的V 4s轨道之间的电荷转移态激发跃迁。
Transparent conductive oxides are widely used in photovoltaic devices and flat panel displays. The knowledge of the dielectric function is essential for the application of transparent conducting oxide thin films. The La2/3Sr1/3VO3(LSVO) thin film was successfully prepared on(LaAlO3)0.3(Sr2AlTaO6)0.35(LSAT) substrate by pulsed laser deposition. The optical properties of the LSVO thin film was measured by spectroscopic ellipsometry. The dielectric function of the LSVO thin film is described by B-spline model and Lorentz+Tauc-Lorentz dispersion model, respectively. The results showed that there are two significant optical transitions located at 3.41 eV and 4.11 eV in the visible region. The red shift of the optical bandgap in the doped LSVO thin film, which is located at 3.41 eV, is about 0.19 eV. The transition(positioned at 4.11 eV) in the high energy region is attribute to the charge transfer excitation involved in O 2 p orbital and the upper unoccupied V 4 s orbital.
作者
赵明琳
童荣景
张少宇
胡友友
Zhao Minglin;Tong Rongjing;Zhang Shaoyu;Hu Youyou(School of Science,Jiangsu University of Science and Technology,Zhenjiang Jiangsu 212003,China)
出处
《应用激光》
CSCD
北大核心
2019年第5期804-808,共5页
Applied Laser
基金
国家自然科学基金资助项目(项目编号:11804126,11874185)
关键词
薄膜
透明导电氧化物
B样条
介电函数
thin films
transparent conducting oxide
B-spline
dielectric function
