光学学报, 2005, 25 (4): 567, 网络出版: 2006-05-22
射频磁控反应溅射氮氧化硅薄膜的研究
Study of Silicon Oxynitride Film Deposited by RF Magnetron Sputtering
薄膜光学 SiOxNy薄膜 磁控溅射 光学常数 禁带宽度 thin film optics silicon oxynitride thin film magnetron sputtering optical constant optical gap width
摘要
利用SiOxNy薄膜光学常数随化学计量比连续变化的特性,给出了制备折射率连续可调的SiOxNy薄膜的实验条件。用磁控反应溅射法制备了不同氮氧比的SiOxNy薄膜。研究了不同气流比率条件下薄膜光学常数、化学成分及溅射速率等的变化。用UV-VIS光谱仪测试了透射率曲线,利用改进的单纯型法拟合透射率曲线计算得到了折射率和消光系数。测试了红外傅立叶光谱(FTIR)曲线和X光光电子能谱(XPS)分析了薄膜成分的变化。实验表明薄膜特性与N2/O2流量比率密切相关,通过控制总压和改变气体流量比可控制SiOxNy薄膜的折射率n从1.92到1.46连续变化,应用Wemple-DiDomenico模型计算出光子带隙在6.5 eV到5 eV之间单调变化。
Abstract
The conditions of depositing graded refractive index silicon oxy-nitride films were studied when the optical properties of the films changed with the composition. SiOxNy thin films of different N/O ratios were deposited by rf magnetron reactive sputtering. Samples' refractive index, extinction coefficient, composition and deposition rate were studied. The transmission curve was measured by using UV-VIS spectrophotometer. A simple and accurate method is presented for determination of the optical constants and physical thickness of thin films. Which consists in fitting the experimental transmission curve with the help of the physical model. The composition of SiOxNy films was analyzed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spoctroscopy (FTIR) characterization methods. The experiments indicated the film characteristics were related closely to the N2/O2 gas flow ratio. As a result, the samples' refractive index can be controlled from 1.92 to 1.46 by adjusting the gas flow and controlling the total pressure, and the optical gap calculated using Wemple-DiDomenico single-oscillator model lies between 5~6.5 eV.
朱勇, 顾培夫, 沈伟东, 邹桐. 射频磁控反应溅射氮氧化硅薄膜的研究[J]. 光学学报, 2005, 25(4): 567. 朱勇, 顾培夫, 沈伟东, 邹桐. Study of Silicon Oxynitride Film Deposited by RF Magnetron Sputtering[J]. Acta Optica Sinica, 2005, 25(4): 567.