系統識別號 | U0002-1408201813012100 |
---|---|
DOI | 10.6846/TKU.2018.00389 |
論文名稱(中文) | 酸性溶液在氮化鎵磊晶層上蝕刻行為之研究 |
論文名稱(英文) | The study of etching on GaN epitaxial layer by acid solution |
第三語言論文名稱 | |
校院名稱 | 淡江大學 |
系所名稱(中文) | 化學工程與材料工程學系碩士班 |
系所名稱(英文) | Department of Chemical and Materials Engineering |
外國學位學校名稱 | |
外國學位學院名稱 | |
外國學位研究所名稱 | |
學年度 | 106 |
學期 | 2 |
出版年 | 107 |
研究生(中文) | 邱彥斌 |
研究生(英文) | Yen-Pin Chiu |
學號 | 605400208 |
學位類別 | 碩士 |
語言別 | 繁體中文 |
第二語言別 | |
口試日期 | 2018-06-20 |
論文頁數 | 77頁 |
口試委員 |
指導教授
-
許世杰(roysos1@gmail.com)
委員 - 陳良益(sampras@mail.ntust.edu.tw) 委員 - 許世杰(roysos1@gmail.com) 委員 - 林正嵐(cllin@mail.tku.edu.tw) |
關鍵字(中) |
氮化鎵 濕式蝕刻 硫酸 硫磷酸 磷酸 |
關鍵字(英) |
GaN wet etching acid solution H2SO4 H3PO4 |
第三語言關鍵字 | |
學科別分類 | |
中文摘要 |
本研究主要探討酸性溶液對於氮化鎵磊晶層之蝕刻行為,藉由三種不同的酸性溶液(硫酸、磷酸、硫磷酸)蝕刻藍寶石基板上的氮化鎵磊晶層,製造出表面粗糙化的氮化鎵結構。實驗中探討不同時間、不同蝕刻液對於表面形貌及蝕刻深度之影響,並使用SEM、AFM、XPS對蝕刻後的樣品進行分析。 實驗結果發現,經過酸性溶液的蝕刻,會在表面形成坑洞。根據不同的蝕刻液的選擇會產生不同的蝕刻形貌。硫酸蝕刻下,氮化鎵磊晶層的厚度並不會有明顯的改變,但會在表面產生倒六角椎的坑洞,並隨著時間增長而擴大、結合,最後會維持在蝕刻面(101 ̅5 ̅);磷酸蝕刻下,氮化鎵磊晶層厚度隨著時間減少,蝕刻坑由倒六角椎形隨著時間轉變為六角柱形,並且坑洞隨著時間延長相互結合,坑洞的大小及深度會隨著時間增加而增加,整體的厚度也會隨著蝕刻時間的增加而減少;硫磷酸蝕刻下,氮化鎵磊晶層厚度隨著時間減少,蝕刻坑會由倒六角椎,漸漸轉為倒十二角椎的坑洞,最後的維持在約為9.3°之夾角。這些坑洞的產生,源於氮化鎵磊晶在藍寶石基板時,因為兩者晶格不匹配所導致的缺陷,而酸性溶液會由這些缺陷開始蝕刻並產生坑洞。 產物方面,在硫酸蝕刻的實驗組中,蝕刻過後可以發現Ga-OEx的峰值提升,且在169.1 eV處產生一硫化物之特徵峰,根據對應為產物Ga2(SO4)3;磷酸實驗中,蝕刻過後可以發現O 1s、P 2p的鍵結峰上升,可以證實磷酸根可能是影響蝕刻的主因;硫磷酸實驗下,反應後之鍵結能並沒有明顯之差異,因此在樣品的表面並沒有發現任何產物。 |
英文摘要 |
This study aims at investigating the etching methods of acid solution to GaN epitaxial layer. It produced the surface roughening GaN structure by the GaN epitaxial layer on the sapphire which was etched by three different acid solutions, which were H2SO4, H3PO4, and H2SO4+H3PO4 (HH). The researcher investigated the influence of different time and etching etchant to surface morphology and etching depth and used SEM, AFM, and XPS to analyze the samples after etching. The results show that the choice of different acid solutions will produce different etching morphologies. Under the H2SO4 etching, the thickness of the GaN epitaxial layer does not change significantly, but the pits of the inverted hexagonal pyramid are generated on the surface, and expand and combine with time, finally remain on the etched surface(101 ̅5 ̅); Under the H3PO4 etching, the thickness of the GaN epitaxial layer decreases with time, and the etch pit will change from inverted hexagonal pyramid to hexagonal prism over time, and the pits will be combined with each other, and the size of the pit and the depth will increase with time; Under the HH etching, the thickness of the GaN epitaxial layer decreases with time, and the etch pit will change from inverted hexagonal to dodecagonal pyramid over time, and finally maintained at an angle of about 9.3°. These etching pits are generated because of the dislocation. When GaN is growth on the sapphire substrate, A lattice mismatch between the two causes dislocation, and the acidic solution begins to etch and create pits from these defects. For the product, the peak of Ga-OEx can be found to increase, and a characteristic peak of a sulfide is generated at 169.1 eV, corresponding product Ga2(SO4)3; in the experimental group of H2SO4 etching; in the H3PO4 experiment, the bonding peak of O 1s and P 2p was found to rise after etching, and it was confirmed that phosphate may be the main cause of etching; In the HH experiment, there was no significant difference in the bonding energy after the reaction, so no product was found on the surface of the sample. |
第三語言摘要 | |
論文目次 |
目錄 致謝 I 中文提要 II 英文提要 III 目錄 V 圖目錄 VII 表目錄 IX 第一章 緒論 1 1-1 LED的發展與重要性 1 1-2 GaN LED的發展 2 1-3 氮化鎵濕式蝕刻的發展與重要性 3 1-4 研究動機與目的 3 第二章 理論背景與文獻回顧 5 2-1 氮化鎵的晶體結構與材料特性 5 2-2 氮化鎵的蝕刻技術 7 2-3 氮化鎵濕式蝕刻技術的發展 9 2-3.1 溼式蝕刻早期發展 9 2-3.2 溼式蝕刻的表面形貌研究 11 2-3.3 溼式蝕刻表面形貌之應用 15 2-3.4 溼式蝕刻表面蝕刻之機制探討 16 2-3.5 結論 19 第三章 實驗方法與步驟 20 3-1 實驗藥品 20 3-2 實驗儀器 21 3-2.1 掃描式電子顯微鏡 21 3-2.2 X射線光電子能譜儀 24 3-2.3 原子力顯微鏡 26 3-3 實驗步驟 28 第四章 實驗結果分析與討論 30 4-1 硫酸溼式蝕刻 32 4-2 磷酸濕式蝕刻 44 4-3 硫磷酸(3:1)溼式蝕刻 51 4-4 表面分析及產物探討 62 第五章 結論 73 第六章 參考文獻 74 圖目錄 圖 1 1 暖白光與冷白光發光效率趨勢圖[1] 2 圖 2 1 六方纖鋅礦結構單位晶格示意圖[21] 6 圖 2 2 Wurtzite 結構常用之平面示意圖[22]。 6 圖 2 3 六方晶系的示意圖[23] 7 圖 2 4 鎵極性面以及氮極性面示意圖[24] 7 圖 2 5 KOH蝕刻氮化鎵表面SEM結果圖[38] 12 圖 2 6 KOH蝕刻氮化鎵表面的AFM結果圖[38] 12 圖 2 7 KOH蝕刻氮化鎵表面的TEM結果圖[38] 13 圖 2 8 KOH蝕刻氮化鎵薄膜表面XPS結果圖[41] 17 圖 2 9 -c方向氮化鎵薄膜蝕刻機制示意圖[41] 18 圖 3 1 S4800掃描式電子顯微鏡外觀 22 圖 3 2 SU8010掃描式電子顯微鏡外觀 23 圖 3 3 XPS基本架構圖[42] 24 圖 3 4 XPS機台外觀 25 圖 3 5 AFM機台外觀圖 27 圖 3 6 實驗裝置圖 29 圖 4 1 氮化鎵與藍寶石基板晶格與面示意圖 31 圖 4 2 尚未蝕刻時平邊的放大圖 31 圖 4 3 蝕刻測量示意圖 32 圖 4 4 硫酸270℃,蝕刻時間10分鐘結果圖 36 圖 4 5 硫酸270℃,蝕刻時間30分鐘結果圖 37 圖 4 6 硫酸270℃,蝕刻時間60分鐘結果圖 38 圖 4 7 硫酸270℃,蝕刻時間90分鐘結果 39 圖 4 8 硫酸270℃,蝕刻時間120分鐘結果圖 40 圖 4 9 硫酸270℃蝕刻氮化鎵薄膜之EPD結果圖 41 圖 4 10 硫酸270℃蝕刻氮化鎵薄膜坑洞之角度結果圖 42 圖 4 11 硫酸270℃蝕刻氮化鎵薄膜之厚度結果圖 43 圖 4 12 硫酸蝕刻機制示意圖 43 圖 4 13磷酸140℃,蝕刻時間5分鐘之SEM結果圖 46 圖 4 14磷酸140℃,蝕刻時間10分鐘之SEM結果圖 46 圖 4 15磷酸140℃,蝕刻時間20分鐘之SEM結果圖 46 圖 4 16磷酸140℃,蝕刻時間30分鐘之SEM結果圖 47 圖 4 17磷酸140℃,蝕刻時間60分鐘之SEM結果圖 47 圖 4 18磷酸蝕刻機制示意圖 48 圖 4 19磷酸140℃蝕刻氮化鎵薄膜之EPD結果圖 49 圖 4 20磷酸140℃蝕刻氮化鎵薄膜坑洞之角度結果圖 50 圖 4 21磷酸140℃蝕刻氮化鎵薄膜之厚度結果圖 51 圖 4 22 硫磷酸270℃,蝕刻時間5分鐘結果圖 55 圖 4 23 硫磷酸270℃,蝕刻時間10分鐘結果圖 56 圖 4 24 硫磷酸270℃,蝕刻時間20分鐘結果圖 57 圖 4 25 硫磷酸270℃,蝕刻時間30分鐘結果圖 58 圖 4 26 硫磷酸270℃,蝕刻時間60分鐘結果圖 59 圖 4 27 硫磷酸蝕刻機制示意圖 60 圖 4 28 硫磷酸270℃蝕刻氮化鎵薄膜之EPD結果圖 61 圖 4 29 硫磷酸270℃蝕刻氮化鎵薄膜坑洞之角度結果圖 61 圖 4 30 硫磷酸270℃蝕刻氮化鎵薄膜之厚度結果圖 62 圖 4 31 不同蝕刻液體之C 1s結合能特徵峰 67 圖 4 32 不同蝕刻液體之O 1s結合能特徵峰 68 圖 4 33 不同蝕刻液體之Ga 2p3/2結合能特徵峰 69 圖 4 34 不同蝕刻液體之N 1s結合能特徵峰 70 圖 4 35 不同蝕刻液體之P 2p結合能特徵峰 71 圖 4 36 不同蝕刻液體之S 2p結合能特徵峰 72 表目錄 表 2 1 酸與鹼蝕刻III族氮化物結果[34] 10 表 2 2不同蝕刻溶液蝕刻氮化鎵薄膜的蝕刻率及蝕刻面[28] 10 表 2 3 HVPE生長氮化鎵薄膜溼式蝕刻條件及表面形貌描述[39] 14 表 3 1 S4800場發掃描式電子顯微鏡規格表 22 表 3 2 SU8010冷場發掃描式電子顯微鏡規格表 23 表 3 3 XPS規格表 25 表 3 4 AFM規格表 27 表 4 1 硫酸270℃蝕刻結果數據表 41 表 4 2磷酸140℃蝕刻結果數據表 48 表 4 3 硫磷酸270℃蝕刻結果數據表 60 表 4 4 不同原子組成所對應之XPS峰值位置表[45] 66 |
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