氮化鋁薄膜光學特性及其應用

The Optical Properties and Applications of AlN Thin Film

邱尉育(Wei-Yu Chiu)

指導教授 ： 高慧玲

中原大學/工學院/電子工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100161

摘要

近年來光電產業日漸蓬勃發展，光電及光學產品的應用日益廣泛，諸如DWDM等當紅的產品皆是光學的應用，未來發展前景更是無可限量，而氮化鋁(AlN)薄膜在光電應用方面擁有甚佳的特性，諸如具有寬能階(~6.2eV)，能利用於紫外光範圍的應用，又具有高硬度及高穿透率(可見光~紅外線範圍)，對於光學薄膜來說不失為一良好的材料，因此我們選擇AlN 這種材料來進行研究。
由於光學常數及薄膜粗糙度對於光學的應用相當重要，因而在本研究中我們利用具有低濺鍍壓力之迴旋磁控濺鍍系統沉積AlN薄膜於SiO2/Si 及quartz上，利用橢偏儀(Spectrometer Ellipsometer)分析及探討製程參數對於折射率(refractive index)和消光係數(extinction coefficient)的影響，並同時利用XRD繞射儀與AFM分析薄膜品質，研究薄膜品質與光學常數的相關性。
在本研究中，我們成功的利用迴旋磁控濺鍍系統沉積具有高折射率(n~2.1)，低消光係數(k~4×10-4)，平均粗糙度僅2Å的AlN薄膜，特別在消光係數方面及表面粗糙度方面，更遠勝一般傳統的磁控濺鍍系統(k介於10-2~10-3, Roughness~20Å) ，並成功的將其應用於雙層抗反射應用，使其基板穿透率由93%增加至96%，為AlN 在光學方面的發展創造更多可行性。

關鍵字

折射率 ； 消光係數 ； 氮化鋁 ； 迴旋磁控濺鍍

並列摘要

AlN thin films were grown on SiO2/Si and quartz substrates using Helicon sputtering system. The dependence of film quality on growth parameters, such as total sputtering pressure, substrate temperature, and nitrogen concentration has been studied. There is a good correlation of thin film crystallinity addressed by XRD and spectroscopic ellipsometer. The optimized films exhibit highly oriented and extremely smooth surface with r.m.s. roughness of 2Å. The extinction coefficient of the film was lower than that of AlN films grown by conventional sputtering. Double layer anti-reflection (DLAR) coating using AlN and Al2O3 grown on quartz has been first time demonstrated. The transmittance of DLAR was high as 96% compared to 93% of bare substrates. AlN films prepared by Helicon sputtering thus are potential for optical application.

並列關鍵字

AlN ； helicon sputtering ； extinction coefficient ； refractive index

參考文獻

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