Bi_(3.45)Eu_(0.55)Ti_3O_(12)铁电薄膜的光学性能

Optical Properties of Bi_(3.45)Eu_(0.55)Ti_3O_912) Ferroelectric Thin Films

采用化学溶液沉积法在石英衬底上制备了Bi3.45Eu0.55Ti3O12(BEuT)铁电薄膜,研究了BEuT薄膜的结构和光学性能。XRD测试结果表明,BEuT薄膜皆形成铋层状钙钛矿型结构,其晶粒尺寸随着退火温度的提高而增加。薄膜的光学透过率曲线显示,在大于500nm的波段BEuT的透过率比较高,而其禁带宽度大约为3.61eV。BEuT薄膜的发光强度随着退火温度的提高,先是增强后减弱,在700℃时达到最大。这与薄膜的结晶状况有关。

Bi3.45Eu0.55Ti3O12 （BEuT） thin films were prepared on quartz substrates by using chemical solution deposition technique, and the structural and optical properties of thin films were studied in this work. XRD results show that BEuT thin films exhibit a polycrystalline bismuth-layered perovskite structure, and the average grain sizes increase with increasing annealing temperature. In the wavelength of above 500 nm, BEuT thin films show high optical transmittance, and the band gaps of all samples are nearly about 3.61 eV. The emission spectra of Eu^3＋ ions indicate that the photoluminescence of BEuT thin films is related to the annealing temperature of samples. The emission intensity firstly increases, reaches a maximum for the sample annealed at 700 ℃, and then decreases, which is related to the crystallization of BEuT thin films.