本研究主要是以固態反應法在藍寶石表面生長鎂鋁尖晶石薄膜，利用 物理汽相沈積（PVD）及熱處理製程，生長出具優先取向性之磊晶薄膜， 並透過後續檢測等技術，確定其薄膜的成分與結構等性質。同時，藉由熱 處理的製程參數之控制，逐步探討參數條件如何影響表面薄膜的成分與性 質改變。 在實驗結果可以發現，反應薄膜在不同的熱處理溫度下，會有不同的 反應速率，並隨著溫度的升高而增加；並且在氧化鎂未反應完全之前，尖 晶石生成物之反應層厚度也會隨著熱處理時間的增加而增加，呈現線性的 變化趨勢。此外，在薄膜的磊晶方向上，由XRD 實驗得知在不同軸向的 氧化鋁基板，會形成不同方向性的尖晶石磊晶層，並發現（hhh）方向之 Mg-Al spinel 容易生長在C軸及A軸氧化鋁上，而（hh0）方向之Mg-Al spinel 則易生長在M 軸氧化鋁基板上。同時透過平面上方向的量測與表面結構的 觀察，可以獲得spine 磊晶層與sapphire 基板間in-plane 方向上的關係。另 外也可以確定的是spinel（hhh）生長的結構面為三方對稱形紋路，且表面 的對稱結構之方位與原子排列結構的方向有關。透過此篇論文在氧化鋁基 板上生成鎂鋁尖晶石所做的各項性質探討，可以作為生長其他spinel 結構 之磊晶薄膜的參考依據。 In this study, an epitaxial Mg-Al spinel layer was successfully grown on a sapphire single crystal surface using solid-state reactions. The processes of solid-state reactions with PVD and heat treatment were applied to grow epitaxial layer with preferred orientation. And the layer composition and structure can be confirmed by the further analyses. Through the controlling of the heat treatment parameters, the variation of compositions and properties influenced by different conditions on surface layer had been discussed. From the experiment results, reaction layer showed different reaction rate with various heat treatment, and it was proportion to the temperature and duration. In additional, the orientation of epitaxial Mg-Al spinel layer would depend on the cut of sapphire substrate. The hhh-type orientated spinel layer preferred to grow on C- and A-plane sapphire, and the hh0-type orientated spinel layer preferred to grow on M-plane sapphire. Simultaneously, the in-plane orientation relationship between spinel epitaxial layer and sapphire substrate could be obtained by φ scan. The morphology of the epitaxial spinel layer surface will present a particular three-fold symmetrical structure by scanning electron microscope. The model of atomic arrangement was employed to explain the relationship between the surface morphology of spinel and its miller index.
