کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1673937 1008954 2008 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Optical constants of anodic aluminum oxide films formed in oxalic acid solution
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Optical constants of anodic aluminum oxide films formed in oxalic acid solution
چکیده انگلیسی
The anodic aluminum oxide (AAO) films with highly ordered nanopore arrays were prepared in oxalic acid solution under different anodizing voltage and time, its surface and cross section appearances were characterized by using field emission scanning electron microscopy, the transmission spectra with the interference fringes were measured at normal incidence over the wavelength range 200 to 2500 nm. Then the modified Swanepoel method was used for the determination of the optical constants and thickness of the free standing AAO films. The results indicate that the refractive index increases with the increase of anodizing voltage and the decrease of anodizing time, which is mainly due to the content of Al2O3 with octahedron increases in the AAO films. The dispersion of the refractive index is discussed in terms of the single-oscillator Wemple-DiDomenico model, and the energy dependence of the absorption coefficient can be described using the direct transition model proposed by Tauc. Likewise, the optical energy gap Eg is derived from Tauc's extrapolation, and Eg increases from 4.178 to 4.256 eV with the anodizing voltage, but is weakly dependent on anodizing time. All the results are self-consistent in the paper.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Thin Solid Films - Volume 516, Issue 21, 1 September 2008, Pages 7689-7694
نویسندگان
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