利用電漿輔助式分子束磊晶法在藍寶石基板上成長氧化錳鋅的物理特性研究

Physical properties of ZnMnO epilayers grown on c-Al2O3 by Plasma-assisted Molecular Beam Epitaxy

羅為宣(Wei-Hsuan Lo)

指導教授 ： 王智祥

中原大學/理學院/應用物理研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700417

摘要

本論文運用電漿輔助式分子束磊晶技術在三氧化二鋁基板（0001）表面上，直接成長三元化合物氧化錳x鋅1-x薄膜，分別在650℃和450℃兩不同溫度下成長兩組不同錳濃度的氧化錳x鋅1-x薄膜，而氧化錳鋅薄膜中錳濃度藉由不同錳分子束源的溫度來控制。將製成的樣品，以X光粉晶繞射儀觀察氧化錳x鋅1-x薄膜的晶體結構，利用原子力顯微鏡觀察氧化錳x鋅1-x薄膜的表面形貌，以及使用X光光電子能譜術確認三元化合物氧化錳x鋅1-x的化學組成，並透過吸收譜判斷氧化錳x鋅1-x薄膜的能隙，以及透過光激螢光光譜和拉曼光譜量測氧化錳x鋅1-x薄膜的光學特性。研究結果顯示，在650℃下成長的樣品在錳濃度較高時會出現其他結晶相訊號，而在450℃下成長的樣品則無。在成長氧化鋅薄膜時，加入少量的錳，對於改善樣品表面粗糙度有顯著的貢獻。而當樣品在錳濃度低的時，能帶與錳濃度的關係呈現一個能帶彎曲，隨著錳濃度的增加則能隙也隨呈線性增加。在能量高於樣品能隙的光激螢光光譜看到了共振拉曼散射多聲子模式，且光激螢光的強度隨著錳含量的增加而減弱。比較氧化鋅與氧化錳鋅的拉曼光譜，與錳有關的聲子模式出現在518 cm-1。

關鍵字

氧化錳鋅 ； 分子束磊晶

並列摘要

Ternary Zn1-xMnxO epilayers were grown on c-Al2O3 using plasma assisted molecular beam epitaxy at growth temperature 650℃ and 450℃. The concentration of Mn was varied through varying the temperature of Mn cell. X-ray diffraction (XRD) , atom force microscopy (AFM) , x-ray photoelectron spectroscopy(XPS) , absorption spectra, photoluminescence (PL) and Raman spectra were used to characterize the film properties, such as the crystal structure, surface morphology, chemical and optical properties. The films with high Mn concentration at growth temperature of 650℃ had peak related to secondary phases was observed, but not observed at growth temperature of 450℃. Small amount Mn incorporation can significantly improve surface roughness. The band-gap of ZnMnO thin film, determined from the absorption spectra, as a function of Mn content displays a bowing deviation. The resonance Raman scattering multi-phone mode was revealed in the PL by the exciting photon energy higher than the direct band gap. However, the PL intensity was quenched with Mn incorporation. Compared with the Raman spectra for ZnO film, the Mn relation phonon mode was revealed at around 518 cm-1.

並列關鍵字

Molecular Beam Epitaxy ； ZnMnO

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