Tb∶Lu_2SiO_5光学薄膜的结构演变和发光性能

Structure Evolution and Luminescent Properties of Tb∶Lu_2SiO_5 Optical Thin Films

采用溶胶-凝胶法结合旋涂工艺在单晶硅(111)上制备了Tb^(3+)离子不同掺杂浓度的硅酸镥光学薄膜(Tb∶Lu_2SiO_5),利用热重差热分析(TG-DSC)、X射线衍射(XRD)、傅里叶红外光谱仪(FTIR)、原子力显微镜(AFM)和紫外可见荧光光谱(PL)对Tb∶Lu_2SiO_5薄膜的不同温度热处理的结构演变和发光性能进行了表征。研究结果表明Tb∶Lu_2SiO_5光学薄膜表面均匀、平整、无裂纹,薄膜样品从800℃开始晶华,1100℃时晶化完全。Tb∶Lu_2SiO_5的发光性能表现为Tb^(3+)离子的4f→5d和5D4(5D3)→7FJ(J=6,5,4,3)跃迁结果(监测波长分别为480~650 nm和350~470 nm),激发主峰位于~240 nm,发射光谱主峰为542 nm的绿光发射。研究表明Tb^(3+)掺杂浓度对Tb∶Lu_2SiO_5光学薄膜的发光强度会产生明显影响,掺杂15mol%的Tb^(3+)时,Tb∶Lu_2SiO_5薄膜的发光强度最强。

lutetium oxyorthosilicate（Tb∶ Lu2SiO5） optical films with different Tb^3＋doping concentration have been fabricated on silicon（111） substrates by Pechini sol-gel method combined with the spincoating technique.Thermogravimetry-differential scanning calorimetry（TG-DSC） analysis, X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR）,Atomic force microscope（AFM）and Photoluminescent（PL） measurements were used to characterize the resulting optical films.The results indicate that the optical films were uniform,densify and crack-free,and the prepared films begin to crystallize at about 800 ℃ and are completely crystallized at 1100 ℃.The PL spectra show that it consists of four major peaks due to the^5D4-^7FJ（J = 6,5,4,3） transition between the wavelengths of480-650 nm and some minor peaks due to the^5D3-^7FJ（J = 6,5,4,3） transition of Tb^3＋in the wavelength range of 350-470 nm,with the strongest emission for^5D4-^7F5 at 542 nm.The Tb^3＋doping concentration has significant effect on luminous intensity of as-prepared Tb∶ Lu2SiO5films.According tothe luminous intensity of the Tb∶ Lu2SiO5films,doping with about 15mol% Tb^3＋is the optimal doping concentration in this presented paper.