射頻反應磁控濺鍍YSZ/SiO2光學薄膜之研究

The preparation of YSZ/SiO2 optical films by R.F. magnetron sputtering system

彭智偉(Chih-Wei Peng)

指導教授 ： 張慎周

崑山科技大學/工程學院/電機工程研究所/碩士(2004年)

摘要

本實驗主旨分別在利用YSZ當高折射率材料與SiO2當低折射率材料，進一步分別對其做光性與物性方面的探討；利用射頻磁控濺鍍系統分別將YSZ與SiO2沉積在p-type（100）與Quartz基板上，並利用穿透率光譜儀量測穿透率、橢圓偏光儀量測折射率與消光係數、原子力顯微鏡量測表面粗糙度、X光繞射儀量測薄膜結晶性，找到製程最佳化之條件。
研究中發現，當通入氧流量時，薄膜因O－的背向濺鍍效應使得沉積速率降低、粗糙度上升，導致光學性質較差；當基板溫度上升，提供濺鍍出之分子在基板上之動能，增加其遷移率，使得粗糙度降低，光學性質提昇，但當溫度過高，將使薄膜呈現結晶態，將使光學性質降低。當提昇工作壓力時，因平均自由徑的降低，使得濺鍍出之分子動能因碰撞而損耗，導致沉積速率、粗糙度及光學性質都會降低。由上述便可找出製程最佳參數，進而製鍍出最佳品質之薄膜。
本實驗中，當YSZ沉積條件為濺鍍必v260 W、濺鍍壓力2.5 mTorr、O2/Ar = 0﹪以及基板溫度為300℃時，YSZ薄膜具有最高穿透率92.65﹪與折射率2.344及最低消光係數0.0051；當SiO2沉積條件為濺鍍必v220 W、濺鍍壓力1 mTorr、O2/Ar = 0﹪以及基板溫度為300℃時，SiO2薄膜具有最高穿透率94.01﹪與折射率1.486及最低消光係數0.0013。
本實驗將以YSZ為高折射率材料，SiO2為低折射率材料，使用Essential Macleod光學薄膜設計軟體，進行紫外光區抗反射膜的設計與製作。疊加實驗結果顯示YSZ與SiO2薄膜在紫外光區（λ= 365 nm）是具有高穿透（99%）潛力之光學薄膜。

關鍵字

射頻反應磁控濺鍍 ； 紫外光光學薄膜

並列摘要

In this study, the Yttria-stabilied zirconia (YSZ) and SiO2 thin films, which are high and low optical refractive index material, respectively, were prepared by rf. sputtering at room temperature. A series of film preparation parameters including sputtering power, partial oxygen pressure (O2 /（Ar+O2）ratio) and film thickness on the optical properties and the microstructures of YSZ and SiO2 thin films that were investigated by spectrometer, ellipsometer, X-ray diffractometer and atomic force microscopy.
By varying process parameters, the optimum conditions for the highest optical transmittance and lowest surface roughness are found. The surface roughness of YSZ thin films increased as function of the O2 /（Ar+O2）ratio. The excessive amount of oxygen flow during deposition induces the back sputtering, leading to hinder the film growth rate which in turn, deterioration of the optical properties. As the substrate temperature increases, the average mobility of all species increases resulting in improved crystallinity. The effect of substrate temperature on the crystallinity is related to the mobility of the various species adsorbing onto the substrate surface. High crystalline results at high substrate temperature that contributes to lowest surface smoothness and reasonable optical properties.
It is clarified that the optical properties depended on the substrate temperature. The highest optical transmittance of 92.65%, refractive index of 2.344 and extinction coefficient of 0.0051 were achieved when the YSZ thin films deposited on a 300℃ heated substrate. The highest optical transmittance of 94.01%, refractive index of 1.486 and extinction coefficient of 0.0013 were obtained with the SiO2 thin films deposited on a 300℃ heated substrate.
Based on the analysis of optical spectrum from the YSZ and SiO2 thin films and the Essential Macleod CAD software. The results of the processing parameters and material properties of YSZ and SiO2 films will unify to fabricate anti-refraction thin films in the UV region. A hybrid high-low refractive index optical thin film with high transmittance was attained 99% at the wavelength of 365 nm.

並列關鍵字

R.F. magnetron sputtering system ； UV optical thin film

參考文獻

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