臺灣博碩士論文加值系統

本研究第一部份乃應用溶膠凝膠法結合旋轉塗佈法製備p型二氧化錫基半導體薄膜，探討鎵摻雜濃度對二氧化錫半導體薄膜之顯微組織及光、電特性的影響。研究結果顯示隨鎵摻雜量增加二氧化錫基薄膜之平均晶粒尺寸變小、表面粗糙度下降；當鎵摻雜濃度達15% 時，能獲得電洞濃度最高(1.70×1018 cm-3) 之p型二氧化錫基半導體薄膜，其載子遷移率與電阻率分別為6.34 cm2/Vs及1.56 Ω cm。此外，本研究也將製備之p型二氧化錫基薄膜結合濺鍍法沉積之n型鋁摻雜氧化鋅 (AZO) 薄膜，研製出p-n異質接面； p型二氧化錫/n型氧化鋅異質接面之順向偏壓開路電壓為0.65 V、理想因子則約為12.44。
第二部份則應用紫外光輔助照射於低溫熱處理環境製備二氧化錫基半導體薄膜。研究中探討紫外光照射時間對薄膜光、電性質之影響並與傳統熱處理退火程序所製備樣品物理性質比較。紫外光照射有助於凝膠薄膜有機物質的裂解及促進金屬離子-氧離子鍵結速率，因此能形成緻密的薄膜並大幅降低薄膜製程溫度。研究結果顯示溶凝膠薄膜於300℃烘烤並經紫外光照射1至4小時後，相較於熱處理薄膜樣品其薄膜結晶性較差且無明顯顆粒形貌，此外，未摻雜二氧化錫薄膜表面之平整度、膜厚均勻性與表面粗糙度相較於鎵摻雜二氧化錫薄膜為差。紫外光照射4小時之二氧化錫薄膜樣品其電子濃度為1.88×1018 cm-3、電阻率則為0.98 Ω cm；鎵摻雜二氧化錫薄膜樣品電洞濃度為9.87×1017 cm-3、電阻率則為1.79 Ω cm。另外本研究也成功製備出氧化錫紫外光感測器，量測結果顯示元件經UVC波段紫外光照射，其反應時間為6 s、光響應值則為9.70 A/W。

In this study, solution-processed tin oxide (SnO2) semiconductor thin films and photodetectors were fabricated on glass substrates at a low operating temperature using ultraviolet (UV) light irradiation. The first part, author prepared p-type SnO2-based semiconductor thin films by sol-gel spin coating method and investigates the influence of Ga doping concentration on microstructural, optical, and electrical properties of tin oxide (SnO2) thin films. Experiemtal results showed that the average grain size and surface RMS roughness of Ga-doped SnO2 (SnO2:Ga) decreased with increasing Ga doping concentration. The nature of conductivity in SnO2:Ga thin films changed from n-type to p-type when the Ga doping level achieved at 10% and the 15% Ga-doped SnO2 thin films exhibited the highest mean hole concentration of 1.70×1018 cm-3 and had a resistivity of 1.56 Ω cm. In addition, author fabricated the p-n heterojunction by using sputtering deposition n type Al-doped ZnO (AZO) onto p type SnO2-based thin films. The p type SnO2/n type ZnO heterojunction had a forward turn-on voltage of 0.65 V, and a ideal factor of 12.44.
The second part, author prepared SnO2-based semiconductor thin films by UV assisted irradiation and low temperature annealing. The effect of light irradiation time on the optical and electrical properties of SnO2-based thin films was investigated and physical properties of the UV light irradiated and thermally annealed thin films samples were compared. In this study, the sol-gel film was dried at 300℃ and using UV light irradiation for 1 to 4 h. It was found that the low-temperatrue processd thin films exhibited poor crystallization and no significant particle morphology compared with thermally annealed samples. The dried SnO2-based sol-gel film was irradiated for 4 h could exhibit the best electrical properties. The SnO2 thin films had a electron concentration of 1.88×1018 cm-3, and a resistivity of 0.98 Ω cm; the Ga-doped SnO2 thin films exhibited a hole concentration of 9.87×1017 cm-3, and a resistivity of 1.79 Ω cm. Furthermore, author successfully fabricated the tin oxide UV detectors. Measured results showed that the UV detector devices exhibited the response time of 6 s and had the responsivity of 9.70 A/W.

總目錄
誌謝...................................I
中文摘要...............................II
Abstract.............................III
總目錄.................................IV
圖目錄...............................VIII
表目錄................................XII
第一章 前言.............................1
第二章 文獻回顧..........................3
2.1 氧化錫 (SnOx) 基本特性及應用..........3
2.1.1 氧化錫的歧化反應 (Disproportionation reaction)............................3
2.1.2 二氧化錫基本特性...................6
2.1.3 二氧化錫應用 ......................10
2.2 摻雜異質元素對半導體特性之影響.........11
2.3 p型二氧化錫 (p-type SnO2)..........15
2.3.1 缺陷對二氧化錫的影響...............15
2.3.2 氧氣氛對二氧化錫的影響.............17
2.3.3 異質元素摻雜對p型二氧化錫影響.......18
2.4 溶膠凝膠法.........................20
2.4.1 溶膠凝膠法簡介....................20
2.4.2 溶膠凝膠鍍膜製程..................22
2.4.3 溶膠凝膠法之優缺點.................24
2.4.4 影響溶膠凝膠法的因素...............24
2.5 旋塗法.............................25
2.6 紫外光照射 (Ultraviolet irradiation)....................................26
2.6.1 紫外光照射簡介....................26
2.6.2 薄膜紫外光照射特性.................27
2.7 p-n接面體 (p-n junction)...........29
2.7.1 p-n接面體特性....................29
2.7.2 p-n接面體工作原理.................31
2.8 紫外光感測器 (Ultraviolet photodetector)....................................34
2.8.1 紫外光感測器簡介..................34
2.8.2 光導感測器結構與原理...............36
第三章 實驗方法與步驟....................38
3.1 實驗前的規劃........................38
3.2 實驗藥品、基材與儀器.................39
3.3 實驗流程...........................41
3.4 二氧化錫基之溶膠凝膠的合成............43
3.5 溶膠凝膠特性分析....................44
3.5.1 pH酸鹼值量測.....................44
3.5.2 熱分析...........................44
3.6 薄膜製備...........................45
3.6.1 熱退火薄膜製備....................45
3.6.2 紫外光輔助照射低溫退火薄膜製備.......46
3.7 薄膜特性分析........................48
3.7.1 薄膜之晶體結構分析.................48
3.7.2 薄膜表面形貌觀察與粗糙度檢測........48
3.7.3 薄膜顯微結構觀察..................48
3.7.4 薄膜光學特性分析..................49
3.7.5 薄膜之表面成份分析.................49
3.7.6 薄膜電性量測 ......................49
3.8 半導體元件之製備與特性分析............51
3.8.1 p-n異質接面體之製備...............51
3.8.2 熱退火二氧化錫紫外光感測器之製備.....52
3.8.3 紫外光輔助照射低溫退火二氧化錫紫外光感測器之製備...............................52
3.8.4 半導體光電元件微結構觀察............54
3.8.5 半導體光電元件電性分析.............54
3.8.6 紫外光感測器之光響應量測............54
第四章 結果與討論.......................55
4.1 二氧化錫基溶膠凝膠特性分析............55
4.1.1 二氧化錫基溶膠凝膠溶液之pH酸鹼度值量測....................................55
4.1.2 二氧化錫基溶膠凝膠溶液之熱分析.......55
4.2 二氧化錫基薄膜特性分析...............57
4.2.1 二氧化錫基薄膜之晶體結構分析........57
4.2.2 二氧化錫基薄膜之顯微結構觀察與表面形貌分析....................................60
4.2.3 二氧化錫基薄膜之光學特性分析........64
4.2.4 二氧化錫基薄膜之表面成份分析........68
4.2.5 二氧化錫基薄膜之電性量測............72
4.2.6 p-n異質接面體之特性分析............75
4.2.7 p型二氧化錫基半導體薄膜穩定性量測 (Lifetime).................................78
4.3 紫外光輔助照射低溫退火二氧化錫基薄膜特性分析....................................82
4.3.1 二氧化錫凝膠薄膜之光吸收特性........82
4.3.2 二氧化錫基薄膜之晶體結構分析........83
4.3.3 二氧化錫基薄膜之顯微結構觀察與表面形貌分析....................................85
4.3.4 二氧化錫基薄膜之光學特性分析........90
4.3.5 二氧化錫基薄膜之表面成份分析........94
4.3.6 二氧化錫基薄膜之電性量測...........101
4.3.7 二氧化錫紫外光感測器之特性分析......104
第五章 結論...........................111
參考文獻..............................112
圖目錄
圖 2-1 Sn-O 相圖........................4
圖 2-2 一氧化錫晶體結構...................5
圖 2-3 氧化錫之Ellingham圖 ...............5
圖 2-4 氧化錫 (SnOx) 之TEM選區繞射圖......5
圖 2-5 氧化錫 (SnOx) 之X光繞射圖..........5
圖 2-6 二氧化錫晶體結構...................7
圖 2-7 二氧化錫在富氫條件下之本質缺陷形成能 (Formation energy).......................7
圖 2-8 二氧化錫狀態密度與部份狀態密度.......8
圖 2-9 (a) 費米階補償效應、(b) 化學位能效應....................................13
圖 2-10 各種氧化物半導體的能帶圖..........14
圖 2-11 (a) 氫離子插入至SnO2晶體結構中、(b) 氫離子 ( ) 置換SnO2晶格中的氧離子.........16
圖 2-12 III族元素摻雜取代錫離子之缺陷形成能與費米能階的關係 (a) 富錫條件下與圖 (b) 富氧條件下....................................19
圖 2-13 溶膠-凝膠製程...................21
圖 2-14 旋轉塗佈的步驟..................25
圖 2-15 溶凝膠塗佈於基板經紫外光照射產生光化反應後形成緻密的金氧離子網狀結構圖...........28
圖 2-16 在250℃下熱處理之未經UV光照射與經UV光照的ZTO薄膜的Id-Vg電性轉換特性圖..........28
圖 2-17 (a) p型與n型半導體接面接合之電子與電洞的分布狀態 (b) 熱平衡時之p-n接面的能帶圖.30
圖 2-18 (a) 施加順向偏壓後之p-n接面體電子與電洞的分布狀態 (b) 施加順向偏壓後之p-n接面的能帶圖....................................32
圖 2-19 (a) 施加逆向偏壓後之p-n接面體電子與電洞的分布狀態 (b) 施加逆向偏壓後之p-n接面的能帶圖....................................32
圖 2-20 一理想p-n接面體之I-V曲線圖.......33
圖 2-21 紫外光感測器種類示意圖............35
圖 2-22 光導感測器之結構.................37
圖 2-23 氧化物半導體光導感測器之氧氣的吸附與脫附效應.................................37
圖 3-1 二氧化錫基半導體薄膜之實驗流程圖....41
圖 3-2 紫外光輔助照射低溫退火二氧化錫基半導體薄膜之實驗流程圖..........................41
圖 3-3 p-n接面體研製流程圖...............42
圖 3-4 紫外光感測器研製流程圖.............42
圖 3-5 紫外光輔助照射低溫退火薄膜製備示意圖.47
圖 3-6 霍爾量測裝置示意圖................50
圖 3-7 p-n異質接面結構示意圖.............51
圖 3-8 紫外光感測器結構示意圖.............53
圖 4-1 SnO2-based溶膠凝膠溶液之pH酸鹼度值.56
圖 4-2 SnO2溶膠凝膠溶液之熱重分析.........56
圖 4-3 SnO2-based薄膜之X光繞射圖........59
圖 4-4 SnO2-based薄膜之織構係數 (Texture Coefficient, TC).......................59
圖 4-5 SnO2-based之SEM薄膜表面影像圖 (a) SnO2、(b) SnO2:Ga 5%、(c) SnO2:Ga 10%、(d) SnO2:Ga 15%、(e) SnO2:Ga 20%..........61
圖 4-6 SnO2-based之SEM薄膜橫截面影像圖 (a) SnO2、(b) SnO2:Ga 5%、(c) SnO2:Ga 10%、(d) SnO2:Ga 15%、(e) SnO2:Ga 20%......62
圖 4-7 SnO2-based薄膜之SPM影像 (a) SnO2、(b) SnO2:Ga 15%.......................63
圖 4-8 SnO2-based薄膜之紫外光-可見光穿透特性曲線..................................66
圖 4-9 SnO2-based薄膜之光學能隙曲線......66
圖 4-10 SnO2-based薄膜之吸收係數與光子能量....................................67
圖 4-11 SnO2-based薄膜之XPS wide scan spectra (a) SnO2、(b) SnO2:Ga 5%、(c) SnO2:Ga 10%、(d) SnO2:Ga 15%、(e) SnO2:Ga 20%....................................70
圖 4-12 SnO2-based薄膜之 (a) Sn、(b) O、(c) Ga元素core-level XPS能譜圖.........71
圖 4-13 SnO2-based薄膜之載子濃度 (n)、載子遷移率 (μ) 與電阻率 (ρ)...................74
圖 4-14 p型SnO2:Ga與n型ZnO:Al之異質接面體之能帶圖.................................76
圖 4-15 銦電極沉積於p型SnO2:Ga與n型ZnO:Al之電流-電壓曲線圖.........................76
圖 4-16 p-n異質接面體之電流-電壓曲線圖....77
圖 4-17 p-n異質接面體之理想因子..........77
圖 4-18 二氧化錫凝膠薄膜與玻璃基板之吸收係數....................................82
圖 4-19 熱退火與紫外光輔助照射低溫退火SnO2薄膜之X光繞射圖............................84
圖 4-20 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之X光繞射圖...................84
圖 4-21 熱退火與紫外光輔助照射低溫退火SnO2薄膜之SEM橫截面影像圖 (a) 熱退火、(b) UVI-1h、(c) UVI-2h、(d) UVI-3h、(e) UVI-4h....87
圖 4-22 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之SEM橫截面影像圖 (a) 熱退火、(b) UVI-1h、(c) UVI-2h、(d) UVI-3h、(e) UVI-4h.....................................88
圖 4-23 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之SPM影像 (a) 熱退火、(b) UVI-1h、(c) UVI-2h、(d) UVI-3h、(e) UVI-4h..89
圖 4-24 熱退火與紫外光輔助照射低溫退火SnO2薄膜之紫外光-可見光穿透特性曲線比較............91
圖 4-25 熱退火與紫外光輔助照射低溫退火SnO2薄膜之光學能隙比較..........................91
圖 4-26 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之紫外光-可見光穿透特性曲線比較..92
圖 4-27 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之光學能隙比較.................92
圖 4-28 熱退火與紫外光輔助照射低溫退火SnO2薄膜之XPS wide scan spectra (a) 熱退火、(b) UVI-1h、(c) UVI-2h、(d) UVI-3h、(e) UVI-4h.....................................96
圖 4-29 熱退火與紫外光輔助照射低溫退火SnO2薄膜之 (a) Sn、(b) O元素core-level XPS能譜圖....................................97
圖 4-30 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之XPS wide scan spectra (a) 熱退火、(b) UVI-1h、(c) UVI-2h、(d) UVI-3h、(e) UVI-4h............................99
圖 4-31 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之 (a) Sn、(b) O、(c) Ga元素core-level XPS能譜圖......................100
圖 4-32 熱退火與紫外光輔助照射低溫退火SnO2薄膜之電子濃度 (n)、載子遷移率 (μ) 與電阻率 (ρ)..................................102
圖 4-33 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之電洞濃度 (n)、載子遷移率 (μ) 與電阻率 (ρ).............................103
圖 4-34 (a) 紫外光感測器之金屬遮罩、(b) 紫外光感測器鋁電極之線寬及線間距示意圖........106
圖 4-35 不同光源照射對熱退火二氧化錫光感測器之I-V曲線圖.............................107
圖 4-36 UVC光源照射對熱退火二氧化錫光感測器之光響應曲線圖...........................107
圖 4-37 熱退火二氧化錫光感測器再線性量測..108
圖 4-38 不同光源照射對紫外光輔助照射低溫退火二氧化錫光感測器之I-V曲線圖...............109
圖 4-39 不同光源照射對紫外光輔助照射低溫退火二氧化錫光感測器之光響應曲線圖.............109
圖 4-40 紫外光輔助照射低溫退火二氧化錫光感測器再現性量測............................110
表目錄
表 2-1 二氧化錫基本特性...................9
表 2-2 半導體的摻雜原則..................14
表 2-3 SnO2、ZnO、Al2O3、Ga2O3、In2O3在富氧條件下之ΔHf..........................19
表 3-1 實驗藥品........................39
表 3-2 實驗儀器........................40
表 4-1 SnO2-based薄膜之平均晶粒尺寸與晶格常數....................................58
表 4-2 SnO2-based薄膜之光學特性.........67
表 4-3 SnO2-based薄膜之組成含量與束縛能...71
表 4-4 SnO2-based薄膜之電性的影響........74
表 4-5 SnO2薄膜之穩定性測試..............79
表 4-6 SnO2:Ga 5% 薄膜之穩定性測試.......79
表 4-7 SnO2:Ga 10% 薄膜之穩定性測試 ......80
表 4-8 SnO2:Ga 15% 薄膜之穩定性測試 ......80
表 4-9 SnO2:Ga 20% 薄膜之穩定性測試......81
表 4-10 熱退火與紫外光輔助照射低溫退火SnO2薄膜之光學特性.............................93
表 4-11 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之光學特性....................93
表 4-12 熱退火與紫外光輔助照射低溫退火SnO2薄膜之組成含量與束縛能.......................97
表 4-13 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之組成含量與束縛能............100
表 4-14 熱退火與紫外光輔助照射低溫退火SnO2薄膜之電性的影響...........................102
表 4-15 熱退火與紫外光輔助照射低溫退火SnO2:Ga 15% 薄膜之電性的影響.................103
表 4-16 熱退火二氧化錫光感測器之光、暗電流值與光響應值..............................108
表 4-17 紫外光輔助照射低溫退火二氧化錫光感測器之光、暗電流值與光響應值.................110

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