With the development of Si-based optical integrated circuit, much attention has been paid to the crystalline and amorphous (BaxSr1-x )TiO3 (BST) films due to its good optical properties.In this study, the amorphous Ba0.7Sr0.3TiO3(BST0.7) thin films were grown on the fused quartz and silicon substrates at low temperature by using a metal organic decomposition (MOD)-spin-coating procedure from barium 2-caprylate Ba (C5H15O2 )2 and 3-methylbutyl acetate CH3COOC2H4CH( CH3 )2-based special precursors.The optical constants of amorphous BST0.7 thin films including refractive index, extinction coefficient and optical band gap energies were presented.Photoluminescence spectra of BST0.7 films were also observed.The calculated extinction coefficient of 214-nm-thick amorphous BST0.7 thin films in visible and near-infrared region was of the order of 10-3, which is much lower than that of polycrystalline BST thin films.The optical band gap energy and refractive index n were estimated to be about 4.27 eV and n = 1.94, respectively.Intensive photoluminescence at room temperature was achieved in the 520 to 610 nm wavelength range with a strong visible peak at 540-570 nm when excited by 450 nm laser light.No photoluminescence was observed in crystalline BST0.7 thin films.%本文采用2-辛酸钡(Ba(C8H15O2)2)和3-甲基丁基醋酸盐(CH3COOC2H4CH(CH3)2-)为基的特殊前驱体溶液,在硅和石英基片上低温制备Ba0.7Sr0.3TiO3(BST0.7)薄膜.性能测试结果表明,厚度约为214 nm的非晶BSTO.7薄膜的光学带隙能和折射率分别为4.27eV和n=1.94.薄膜在可见光和近红外区域的消光系数远远低于多晶BST薄膜,约为10-3数量级.激发波长为450 nm时,在室温环境下非晶BST0.7薄膜在波长520-610 nm处发出强烈的可见光,峰值为540-570 nm,而结晶态的BST0.7薄膜则无发光现象.
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