| 摘要: | 本論文將探討與比較在不同製程與不同起始材料下所製鍍出的二氧化矽薄膜的特性。利用目前最常用的三種物理氣相沉積方法：電子槍蒸鍍、離子束濺鍍、磁控濺鍍三種製程方法，以Si與SiO2為起始材料分別製鍍SiO2薄膜，並討論離子助鍍與離子助鍍使用不同工作氣體的影響。製鍍出的薄膜分別以紫外-可見光光譜儀、傅立葉轉換紅外線光譜儀、應力量測干涉儀、原子力顯微鏡、掃描式電子顯微鏡與接觸角量測儀分析各SiO2薄膜的光學、機械、化學性質與微觀結構。 實驗結果顯示，以電子槍蒸鍍加離子助鍍時，可以得到最佳的紫外光光學特性；磁控濺鍍不加離子助鍍次之；磁控濺鍍加離子助鍍與離子束濺鍍所得到的較差。三種製程在可見光的光學性質都不錯，吸收損耗(消光係數)幾乎都可達到3x10-5以下。而離子束濺鍍得到的表面粗糙度最佳、磁控濺鍍次之，電子槍蒸鍍則較差，但輔以離子助鍍後也可以改善到1nm以下的粗糙度。由紅外線光譜的結果可以知道三種製程都可以製鍍出化學匹配比(stoichimetric)良好的SiO2薄膜，除了電子槍製程不加離子助鍍時，以Si為起始材料所製鍍出的SiO2會含有次氧化態的Si2O3；以SiO2為起始材料則會因為吸收水汽而含有Si-OH的結構。在機械特性方面，所有製程得到的SiO2薄膜皆是呈現壓應力的型態，其中以磁控濺鍍製程所得到的應力最小，離子束濺鍍次之，而電子槍蒸鍍所得的應力最大。而根據量測薄膜的接觸角可知，以離子束濺鍍所得到的薄膜其表面能最低，具有較佳之環境穩定性；以磁控濺鍍與電子槍蒸鍍的薄膜則有較大的表面能。 本研究將SiO2薄膜在三種不同製程下的性質做一完整的整理與比較，對於往後在製鍍各種濾光片或在不同狀況下需要製鍍SiO2薄膜時，可以提供一個參考，例如需要紫外光區鍍膜時則選擇電子槍蒸鍍、需要製鍍低損耗的雷射鏡時則選擇離子束濺鍍，需要低應力與塑膠基板的鍍膜則可以選擇磁控濺鍍。 The properties of SiO2 thin films deposited by different process and from different starting material were discussed and compared. Three processes -E-beam gun evaporation, Ion beam sputtering, and magnetron sputtering- were used to deposit SiO2 thin films, and Si and SiO2 were used as starting materials. The influences of ion beam assisted deposition (IAD) and its working gas were also discussed. The SiO2 thin films were then measured by UV-VIS spectrophotometer, FTIR, stress measurement interferometer, AFM, SEM, and contact angle measurement instrument to analyze the microstructure, optical, mechanical, and chemical properties. The results showed that the SiO2 thin films had the best optical properties in UV region when they were deposited by E-beam gun evaporation with IAD; the properties were still good when deposited by magnetron sputtering; when deposited by ion beam sputtering, the properties were worse. The properties were very good in visible region when the SiO2 thin films were deposited by all of these three processes, and the extinction coefficients of all SiO2 thin films were smaller then 3x10-5. The roughness of the SiO2 thin films were the best when deposited by ion beam sputtering, the roughness increased when deposited by magnetron sputtering, and the roughness were the worst when deposited by E-beam gun evaporation. The results of FTIR measurement shown that all the SiO2 thin films were well stoichiometric, exclude the case of the SiO2 thin films deposited by E-Beam gun evaporation without IAD and used Si as the starting material for the Si2O3 bonding structure was observed in the composition and the case by the same process but used SiO2 as the starting material for the Si-OH bonding structure was observed. For the mechanical properties, all the SiO2 thin films showed the compressive stress, and the quantities of stress were the smallest when deposited by magnetron sputtering, those were bigger when deposited by ion beam sputtering, and those were the biggest when deposited by E-beam gun evaporation. From the contact angle measurement results, the SiO2 thin films deposited by ion beam sputtering had the smallest surface energy, which meant that the films were more durable, and the other SiO2 thin films were bigger. In this research, we discussed and compared the properties of SiO2 thin films deposited by different processes in a completed arrangement. It gives good references for deposit SiO2 thin film in different conditions or for special need. For instance, use E-beam gun evaporation to deposit SiO2 thin films for UV coating; use ion beam sputtering to deposit SiO2 thin films for ultra-low loss laser mirror; use magnetron sputtering to deposit SiO2 thin films for low stress or coating on plastic substrate. |
