本研究主要目的為使用反應式磁控頻射濺鍍方法，設計開發一新型交互堆疊之HfO2-x/W/HfO2-x/W多層太陽能選擇性吸收膜，並鍍製於不鏽鋼基板上，以期能運用於極高溫(600~1000°C)的情況下。在鍍製多層膜之前，我們首先分別使用兩種靶材：Hf金屬靶與HfO2陶瓷靶，在不同的O2/Ar氣體通量比(r)鍍製單層HfO2-x薄膜於Si基板上，接著進行不同溫度的後熱處理，以探討與比較其微結構與光學性質；接著設計與製備多層選擇性吸收膜，並進行不同溫度條件的熱處理，探討其性能及結構變化。
本論文實驗結果與討論分為三大部分，第一及第二部份是分別探討Hf金屬靶材和HfO2-x陶瓷靶材在相同濺鍍條件下所鍍製的HfO2-x薄膜，進行不同溫度的熱處理後，其各種材料分析的結果與比較。我們以X光薄膜繞射儀(Thin-film XRD)對HfO2-薄膜進行微結構分析，發現所有剛鍍製好的薄膜皆為多晶態結構，而HfO2靶鍍製的膜在無熱處理和相對低溫下退火(600°C和800°C)時，隨著r值增加，其結晶度變好；而Hf靶鍍製的膜之結晶度則普遍較HfO2靶的好。使用場發射掃描式顯微鏡(FE-SEM)則發現薄膜是由許多顆粒所組成的連續膜，而每個顆粒包含數顆小晶粒。兩種靶材鍍製的HfO2-x薄膜退火前的顆粒間距較大，退火後則變小。X光光電子能譜儀(XPS)則被用來分析薄膜表面及縱深成份分析，發現HfO2-x靶材鍍製之HfO2-x薄膜表面的化學計量比會隨著O2/Ar通量比增加而改善，但是通入過量氧氣反而會降低O/Hf比例；縱深成份分析方面，無熱處理和退火後的薄膜都存在著HfSixOy介面層，這個結果對光學常數(折射率和消光係數)的量測有重大影響。光學常數則透過橢圓分光儀(Ellipsometer)取得，在建立擬合模型時需考慮HfSixOy介面層的存在，而非單純的Si基板和SiO2原生氧化層。結果發現，HfO2-x薄膜折射率隨著O2/Ar比增加而達到一飽和值，過量氧氣通入則使折射率下降。
第三部分則是分別使用紫外光/可見光/近紅外光分光光譜儀(UV/vis/NIR Spectrometer)和傅立葉轉換紅外光譜儀(FT-IR)量測逐層堆疊的多層膜、不同底層W膜厚度的多層膜、和設計後之多層膜於不同溫度退火前後的反射率和放射率光譜，並計算其太陽能吸收率及放射率，以及其結構上的變化。結果發現，逐層堆疊之多層膜所得到的吸收率符合其各層所扮演的角色：HfO2-x層具有增透及抗反射效用、金屬W層則在可見光區有高吸收，紅外光區有高反射的特性；不同底層W膜厚度的多層膜之放射率則隨W層厚度增加而增加，經過600°C退火後也皆增加；設計後的多層吸收膜於不同溫度退火後的吸收率皆較退火前來的高，放射率則隨退火溫度增加而增加。

The goal of this research is to develop a new design of solar selective absorber—alternately stacked HfO2-x/W/HfO2-x/W multilayer coatings on stainless steel substrates for ultrahigh temperature (600~1000°C) applications using a reactive radio frequency (RF) magnetron sputtering deposition system. Before fabricating the multilayer coatings, the microstructure and optical properties of before and after different temperatures annealing individual HfO2-x coatings on Si substrates which were deposited by Hf and HfO2 targets at varied O2/Ar gas flow ratios (r), respectively, were studied. X-ray diffraction (XRD) analysis show that the obtained HfO2-x coatings were polycrystalline. Field emission scanning electron microscopy surface morphology images indicate that the coatings consist of grains having sizes and porosity depending on the ratio. The optical constants (refractive indices and extinction coefficients) of these coatings were obtained using ellipsometry. X-ray photoelectron spectroscope was used to investigate the surface chemistry. Based on these results, selected HfO2-x coatings were used for the fabrication of multilayer absorbers. The ad-deposited multilayer and 600, 800, and 900°C annealed in vacuum with Ar atmosphere coatings were examined using UV/vis/NIR spectrometry and Fourier transform infrared spectrometer. The crystalline structure was also examined using XRD. The solar absorptance of the multilayer absorbers coatings was improved after the annealing but the emittance slightly increased due to occurrence of oxide formation. The relation between material characteristics and the optical properties are presented and discussed.

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