利用反應性直流磁控濺鍍法以Nb與NbO_x靶材為起始材料沉積之Nb_2O_5薄膜特性研究

Properties of Nb_2O_5 Films Deposited by DC Reactive Magnetron Sputtering from Nb and NbO_x as Starting Materials

唐謙仁(Chien-Jen Tang) ； 吳俊賢(Chun-Hsien Wu) ； 江政忠(Cheng-Chung Jaing) ； 周青宏(Ching-Hung Chou)

《真空科技》 32卷3期 (2019/09) Pp. 22~1-22~6

摘要

本研究使用反應性直流磁控濺鍍法分別以Nb與NbO_x靶材製鍍於不同氧氣流量的Nb_2O_5薄膜，並以UV-VIS-NIR光譜儀、光譜式橢圓偏光儀及Fizeau干涉儀量測Nb_2O_5薄膜的光學特性及殘留應力，於使用Nb靶材製鍍Nb_2O_5薄膜時，其靶材表面會與氧氣反應，產生遲滯現象（hysteresis behavior），氧氣流量分別於順向過渡區6.5SCCM、反應區8SCCM及反向過渡區6.5SCCM時，其折射率及消光係數分別為2.345、2.321、2.323及1.35×10^(-5)、2.6×10^(-6)、6.35×10^(-7)，而使用NbO_x靶材則無遲滯現象，氧氣流量1SCCM、2SCCM及4SCCM，其折射率及消光係數分別為2.349、2.329、2.321及2.7×10^(-5)、2×10^(-5)、9.94×10^(-6)，其中以Nb靶材製鍍出的Nb_2O_5薄膜折射率及消光係數較低，其薄膜光學特性較佳，而NbO_x靶材所製鍍的Nb_2O_5薄膜之消光係數較高，但只需較低的氧流量，因此於製程中靶材表面狀態變化較小，製程穩定性較佳。

關鍵字

五氧化二鈮 ； 反應性磁控濺鍍 ； 遲滯現象 ； 光學常數

並列摘要

In this study, Nb_2O_5 films were prepared by the direct-current (DC) magnetron sputtering. The films were made by the Nb and NbO_x target with different oxygen flow rates. The optical properties and residual stresses of Nb_2O_5 films were analyzed by UV-VIS-NIR spectrophotometer, variable angle spectroscopy ellipsometer and Fizeau interferometer. The Nb_2O_5 films were prepared by the Nb target. By adding a variable flow of oxygen, we find the discharge behavior to show the well-known hysteresis loops. At the 550 nm wavelength, the refractive indices and the extinction coefficients of the Nb_2O_5 films were 2.345, 2.321 and 2.323, and 1.35×10^(-5), 2.6×10^(-6), 6.35×10^(-7), respectively, when the oxygen flow rate were forward branch 6.5sccm, 8sccm and backward branch 6.5sccm, respectively. The Nb_2O_5 films were prepared by the NbO_x target. By adding a variable flow of oxygen, the discharge hysteresis did not occur. At the 550 nm wavelength, the refractive indices and the extinction coefficients of the Nb_2O_5 films were 2.349, 2.329 and 2.321, and 2.7×10^(-5), 2×10^(-5), 9.94×10^(-6), respectively, when the oxygen flow rate were 1sccm, 2sccm and 4sccm, respectively. The Nb_2O_5 film would have low refractive index and extinction coefficient for better optical properties by using the Nb target. The Nb_2O_5 film would have higher refractive index and extinction coefficient prepared by the NbO_x target comparing with the films prepared by the Nb target. However, the target status has small change in the environment with lower oxygen flow rates and it results in stable process.

並列關鍵字

Nb_2O_5 film ； Reactive Magnetron Sputtering ； Hysteresis Behavior ； Optical Constants