本研究使用分子束磊晶法在低晶格失配的(100)、(110)和(111)氧化鎂基板上成長氧化亞銅/摻鎂氧化鋅磊晶異質結構，探討退火前處理對氧化鎂基板表面形貌以及磊晶成長的影響。磊晶前以原子力顯微鏡觀察原生氧化鎂基板及經過不同處理後基板的表面形貌和粗糙度，成長磊晶的試片會以X光繞射分析儀分析晶體結構與磊晶品質，以掃描式電子顯微鏡與能量散佈分析儀分析試片表面的形貌與元素成份，以紫外-可見光譜儀量測試片穿透光譜並求得不同鋅含量岩鹽礦摻鎂氧化鋅能隙值。
原子力顯微鏡分析顯示(100)氧化鎂基板經拋光後粗糙度小於1.00 nm，但表面並未觀察到明顯的階差結構。經過退火後的基板表面呈現階差結構，但是有許多粒徑數十奈米的顆粒分布在表面上，以高純水拋光可以移除顆粒，退火和水拋後的表面平均粗糙度降低0.50 nm。(110)氧化鎂原生基板表面充滿孔洞，退火後孔洞被填補，表面變得相當平坦，平坦區域的平均粗糙度約為0.30 nm。(111)氧化鎂基板是帶有高表面能的極性面，拋光後表面仍有明顯刮痕且粗糙度甚大，在1000 oC退火24 小時以上表面原子重新排列後可以形成階差結構，但是平均粗糙度仍高達4.00 nm。X光繞射分析顯示(100)、(110)和(111)基板經過退火後皆能成長高鋅含量的岩鹽礦摻鎂氧化鋅磊晶，成功在表面能較高的(110)和(111)面成功磊晶可歸因於基板經過退火處理後表面平均粗糙度下降，表面階差結構提供良好的成長位置。掃描式電子顯微鏡分析結果顯示岩鹽礦摻鎂氧化鋅磊晶表面是立方突起的顆粒，而纖鋅礦摻鎂氧化鋅薄膜表面則為混亂分佈的迷宮狀圖案，氧化亞銅則為直徑約20 nm的小晶粒形貌。

Cu2O/ZnxMg1-xO epilayers and heteroepitaxial structures were grown on MgO substrates with low lattice mismatch by molecular beam epitaxy. MgO substrates with three orientations: (100), (110) and (111) were used. Special emphasis on the effect of various pre-treatments on the surface morphology and roughness of the substrate surface is studied. The surface morphology of the MgO substrate surface was characterized by atomic force microscopy (AFM). The composition, orientation and crystallinity of the ZnxMg1-xO and Cu2O films were analyzed by X-ray diffraction (XRD)、scanning electron microscopy (SEM)、energy dispersive x-ray spectroscopy (EDS) and UV-Vis spectrometer.
AFM results showed that no terrace structure could be observed on the as-polished (100) surface though its root-mean-square roughness was low. After annealing, the step-and-terrace structure was present associated with particles of tens of nanometers in diameter. These particles could be removed by polishing in water. A smooth and particle-free surface was thus obtained by high temperature annealing and water polishing. The (110) surface exhibited high density of holes which were removed by high temperature annealing. Finally, the as-polished (111) surface filled with scratches and a high roughness value, probably due to its polar character. After annealed at 1000 oC for 24 hours, the terrace structure was resolved though the average roughness is still high. ZnxMg1-xO epilayers with x>0.70 and Cu2O/ ZnxMg1-xO heterostructure were successful grown on the (100), (110) and (111) MgO substrates.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 v
表次 viii
圖次 ix
第一章 前言 1
第二章 文獻回顧與理論基礎 3
2.1 氧化鎂(MgO)基板 3
2.1.1 MgO(100)基板 3
2.1.2 MgO(110)基板 4
2.1.3 MgO(111)基板 5
2.2 氧化鋅晶體結構與相變化 6
2.2.1 氧化鋅的晶體結構 6
2.2.2 氧化鋅的相變化 7
2.3 氧化鋅-氧化鎂二元系統 8
2.3.1 成長摻鎂氧化鋅的方法 9
2.4 氧化鋅和岩鹽礦/纖鋅礦摻鎂氧化鋅的光電特性 11
2.4.1 氧化鋅的光電特性 11
2.4.2 岩鹽礦/纖鋅礦摻鎂氧化鋅的光電特性 12
2.5 氧化亞銅特性 13
2.5.1 成長氧化亞銅的方法 14
2.6 光偵測器 16
2.6.1 氧化亞銅與氧化鋅的異質接面 17
2.6.2 氧化亞銅與氧化鋅異質接面應用於太陽能電池 18
第三章 實驗方法 20
3.1 分子束磊晶成長系統 20
3.2 基板前處理 21
3.3 磊晶成長步驟 23
3.4 試片分析方法 24
3.4.1 原子力顯微鏡分析 24
3.4.2 X光繞射分析 24
3.4.3 掃描式電子顯微鏡分析 24
3.4.4 穿透光譜分析 25
第四章 實驗結果 26
4.1 氧化鎂基板前處理與表面分析 26
4.1.1 MgO(100)基板 26
4.1.2 MgO(110)基板 28
4.1.3 MgO(111)基板 30
4.2 MgO基板退火前處理對成長RS-ZMO磊晶的影響 31
4.3 在不同氧化鎂基板方向上成長摻鎂氧化鋅的分析 33
4.3.1 X光繞射分析 33
4.3.2 表面形貌分析 37
4.3.3 穿透光譜分析 41
第五章 結果與討論 43
5.1 MgO基板前處理 43
5.2 MgO基板前處理對ZMO磊晶的影響 44
5.3 MgO基板上成長Cu2O 44
5.4 MgO基板上成長Cu2O/ZMO異質結構 45
第六章 結論 47
參考文獻 48
表格 54
圖片 59

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