机构地区: 中山大学物理科学与工程技术学院光电材料与技术国家重点实验室
出 处: 《中山大学学报(自然科学版)》 2006年第1期29-32,共4页
摘 要: 采用Sol—Gel工艺,在Si(100)衬底上制备了Ba1-xSrxTiO3(0.1≤x≤0.3)多晶薄膜,并用椭偏光谱仪在光子能量为2.0—5.2eV的范围内,测量了不同Sr含量x下Ba1-xSrxTiO3多晶薄膜的椭偏光谱。建立适当的拟合模型,用最优化法获得了所有样品的光学常数(折射率n和消光系数k)谱及能隙宽度Eg。比较这些结果发现:在低能区,Ba1-xSrxTiO3薄膜的折射率n随Sr含量x的增加无明显变化,但其吸收边向高能方向移动。表明Ba离子被Sr离子取代后,Ba1-xSrxTiO3薄膜的能隙宽度Eg增大。 Ba1-xSr, TiO3 (0. 1 ≤x≤0. 3) (BST) thin films on Si Ellipsometric spectra of BST thin films with various Sr (100) substrates were prepared concentration x were measured in by Sol - Gel the range of photon energy from 2.0 to 5.2 eV. Constructing appropriate fitting models, their optical constants ( refractive index n and extinction coefficient k) spectra and band gap energy Eg are determined by means of optimization. It is found that no apparent difference is observed in the refractive indexes of three BST thin films in the lower photon energy region. The absorption edges of the samples with an increased Sr dopant shift to high photon energy, and the band gap Eg increases.