我們嘗試使用LPCVD在矽基板與藍寶石基板上長出硫化鎵薄膜。我們使用鎵金屬與硫粉當前驅物。載流氣體為96%氬氣與4%氫氣。
經由數次實驗的比較，我們發現使用單一石英小管的擺設方法可以得到最大面積的薄膜。從FE-SEM的影像可以可以觀察到GaS的晶體為斜插在基板上的片狀結構。並且，這些片狀結構晶體主要是從側面成長。從EDS以及XPS的數據中可以發現到薄膜的位置越下游，薄膜的硫鎵比就會越高這個趨勢。並且GaS長在矽基板的硫鎵比會高於長在藍寶石基板上的硫鎵比。由XRD光譜可以發現從基板上刮下的GaS薄膜粉末有兩個還在基板上的GaS所無法觀察到的峰。我們所合成的硫化鎵為rhombohedral，有別於大部分文獻所提到的hexagonal，而且是層狀結構。在PL光譜中，我們發現到了單層與雙層GaS的近帶邊放光和其對應的本質缺陷放光。也發現了3到5層的近帶邊放光。最後還發現了由多層堆疊的GaS產生的應力和特殊的層間缺陷對形成能階相位的影響。

We tried to grow gallium sulfide thin films on silicon and sapphire substrates using LPCVD. We use gallium metal and sulfur powder as current catalysts. The carrier gas was 96% argon and 4% hydrogen.
After several comparisons of experiments, we found that the arrangement method using a single quartz tube can obtain the largest area of the film. From the FE-SEM image, it can be observed that the crystal of GaS is a sheet-like structure obliquely inserted on the substrate. Also, these lamellar crystals grow mainly from the side. From the data of EDS and XPS, it can be found that the further downstream the film is, the higher the sulfur-gallium ratio of the film will be. And the ratio of sulfur to gallium of GaS grown on silicon substrate will be higher than that of sapphire substrate. From the XRD spectrum, it can be found that the GaS thin film powder scraped from the substrate has two peaks that cannot be observed by the GaS on the substrate. The gallium sulfide we synthesized is rhombohedral, which is different from the hexagonal mentioned in most literatures and has a layered structure. In the PL spectrum, we found the near-band-edge emission of monolayer and bilayer GaS and its corresponding intrinsic defect emission. NBE emission of 3 to 5 layers were also found. Finally, the effects of stress and special interlayer defects generated by the multilayer stack of GaS on the formation of the energy level phase are also found.

誌謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VIII
表目錄 XVII
第一章 緒論 1
1.1 前言 1
1.2 研究動機 2
第二章 研究基礎與文獻回顧 3
2.1 GaS基本性質與應用 3
2.2 LPCVD技術 6
第三章 實驗系統與研究方法 9
3.1實驗流程 9
3.1.1前驅物準備 10
3.1.2試片準備 11
3.2製程設備 12
3.3分析方法 14
3.3.1 X光繞射分析儀(XRD) 15
3.3.2場發射型掃描式電子顯微鏡(FE-SEM) 16
3.3.3能量散布光譜儀(EDS) 17
3.3.4 X射線光電子能譜儀(XPS) 18
3.3.5光致激發光光譜儀(PL) 19
3.4實驗規劃與參數 20
第四章 實驗結果與討論 27
4.1製程討論 27
4.1.1無石英管 31
4.1.2單石英管 34
4.1.3雙石英管 43
4.1.4單石英管製程時間結果比較 50
4.1.5單石英管持溫時間的前驅物消耗量 54
4.2 FE-SEM影像及EDS數據分析 56
4.2.1 無石英管樣品 57
4.2.1.1 0X-Si-20-N-1樣品 57
4.2.1.2 0X-Si-20-N-2樣品 62
4.2.2 單石英管樣品 69
4.2.2.1 1C-Si-20-N樣品 69
4.2.3 雙石英管樣品 76
4.2.3.1雙石英管矽基板樣品 76
4.2.3.2雙石英管藍寶石基板樣品 83
4.2.3.3雙石英管加倍載流氣體矽基板樣品 89
4.2.4 持溫時間成長過程系列 98
4.3 XRD光譜分析 101
4.3.1基板上薄膜之XRD光譜 101
4.3.2從基板上刮下之粉末的XRD光譜 110
4.3.3晶相鑑定 116
4.3.3.1排除Ga2S3 116
4.3.3.2確認GaS 121
4.4 PL光譜分析 131
4.4.1 0X-Si-20-N-1樣品的PL光譜分析 131
4.4.2 2C-Si-20-N樣品的PL光譜分析 134
4.4.3 PL光譜450nm - 600nm部分 139
4.4.4 2 layers 147
4.4.5 3~5 layers 152
4.5 XPS數據討論 159
4.5.1 XPS S/Ga討論 159
4.5.2 2C-Si-20-N擬合結果 164
第五章 結論 171
參考資料 173

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