(Pb_(1-x)Sr_x)TiO_3薄膜的结构与光学特性研究

摘要

Lead strontium titanate (Pb_(1-x)Sr_x)TiO_3 (x=0.40, 0.50, 0.60 and 0.70, abbreviated as PST40, PST50, PST60 and PST70, respectively) thin films were deposited on fused quartz substrates using a sol-gel method with spin-coating processing. The structure and optical properties of PST thin films were studied. The results show that the all samples are perovskite cubic structure when the PST thin films are annealed at 750 ℃ for 30 min. Its average grain size is 200～300 nm. The direct band gap energies are 3.74, 3.79, 3.80, and 3.85 eV, respectively for PST40, PST50,PST60 and PST70 thin films annealed at 750 ℃. The band energies are increased with increasing content of strontium.%采用sol-gel法制备(Pb_(1-x)Sr_x)TiO_3 (x=0.40, 0.50, 0.60, 0.70,简称PST40, PST50, PST60与PST70)前驱体溶液,通过旋涂工艺在石英玻璃基片上沉积PST薄膜.研究了PST薄膜的结构和光学特性.结果显示,经750 ℃退火30 min,所得PST薄膜为晶化良好的钙钛矿立方结构,薄膜平均晶粒尺寸为200～300 nm.750 ℃退火的PST40、PST50、PST60和PST70薄膜样品的直接带隙能分别为3.74,3.79,3.80和3.85 eV.随着Sr含量的增加,带隙能增加.