在PMMA上低温沉积TiO_(2)薄膜的光学性能及显微结构

Optical properties and microstructures of TiO_(2)thin film deposited on PMMA at low temperature

采用直流脉冲磁控溅射的方法,在有机玻璃(聚甲基丙烯酸甲酯,PMMA)上沉积了TiO_(2)薄膜。研究了氧气比例、真空度等参数对TiO_(2)薄膜的结构及光学性能的影响。借助椭圆偏振光测试仪、X射线衍射(XRD)仪、分光光度计、原子力显微镜(AFM)等表征手段,分析了薄膜的光学特性、元素组成、结晶性能、及显微结构。结果表明,随氧气比例的增加,薄膜的沉积速率降低,沉积的薄膜的粒径变大,薄膜趋于疏松;在光学性能方面表现为随氧气比例的增加,折射率递减,但可见光透过率增加,反射率谱线出现红移;根据折射率计算的薄膜堆积密度分别为0.95、0.93、0.87、0.88、0.78,与氧气比例反向变化;根据光谱计算的薄膜禁带宽度在3.12~3.14 eV之间,与氧气比例反向变化;随工作真空度的降低,薄膜的沉积速率先升后降,薄膜趋于疏松,折射率下降,根据折射率计算的薄膜堆积密度为0.96、0.95、0.90、0.89、0.88、0.88、0.87,真空度对薄膜可见光透过率具有正向影响,对薄膜的禁带宽度有反向影响,禁带宽度在3.13~3.16 eV之间;本文沉积的TiO_(2)薄膜为无定形态,氧气比例与真空度的变化对其结晶性基本无影响。

TiO_(2)thin films were deposited on low temperature on poly(methylmethacrylate)(PMMA)by DC pulse mag⁃netron sputtering.The effects of oxygen ratio,vacuum degree and other parameters on the structure and optical proper⁃ties of TiO_(2)thin films were studied.With the help of elliptic polarizing light tester,X⁃ray diffraction(XRD)tester,spec⁃trophotometer and atomic force microscope(AFM),the optical properties,element composition,crystallization properties and microstructure of the thin films were analyzed.The experimental result shows that with the increases of oxygen ratio,the deposition rate of the film decreases,the particle size of the film becomes larger,and the film tend to be looser.In term of optical properties,the refractive index deceases with the increase of oxygen proportion,but visible light trans⁃mittance increases,the reflectance appears redshift.The films packing densities calculated according to the refractive in⁃dex are 0.95,0.93,0.87,0.88 and 0.78 respectively,changes inversely with the proportion of oxygen.The band gap of the films calculated according to the spectrum is between 3.12~3.14 eV,changes inversely with the proportion of oxy⁃gen.With the decreases of vacuum,the deposition speed of the film first increased and then decreased.The films tend to be looser,and the refractive index decreased.The packing density of the film calculated according to the refractive index are 0.96,0.95,0.89,0.88,0.88,0.87,the vacuum degree has an positive effect on the visible light transmittance of the film,and has an negative effect on the band gap width of the film,which is between 3.13~3.16 eV,The TiO_(2)thin films deposited in this paper are amorphous,and the oxygen tatio and vacuum degree has little effect on their crystallinity.