臺灣博碩士論文加值系統

本研究利用射頻磁控濺鍍法製備硫化銅銦 (CuInS2) 光吸收層，使用鈉玻璃作為基材，以In/Cu之結構組成，先鍍一層銦再鍍一層銅，藉由控制不同的銅銦濺鍍時間，調控薄膜內銅、銦比例來製備銅、銦金屬前驅物薄膜，最後在硫氣氛下進行硫化程序以獲得硫化銅銦 (CuInS2) 三元化合物薄膜。討論不同金屬前驅物比例對薄膜組成、晶型、厚度、表面型態、導電型態、光學分析及光電化學特性的影響。
由能量分散式X光元素分析儀 (EDAX) 分析可得，理論銦銅比例 (In/Cu ratio) 為0.51 ~ 1.23之間所成長出來的薄膜為銅過量的樣品，而理論銅銦比例 (In/Cu ratio) 為1.54 ~ 2.05間所成長出來的薄膜為銦過量的CuInS2半導體薄膜，且理論銦銅比例 (In/Cu ratio) 為0.51及0.68的樣品經X光繞射分析儀 (XRD) 分析後具有CuS的雜相，理論銦銅比例 (In/Cu ratio) 為1.84及2.05的樣品經X光繞射分析儀 (XRD) 分析後具有In2S3的雜相。由膜厚分析可得樣品的膜厚介於0.818~1.287 μm之間；由光學分析可得知，樣品的直接能隙位於1.39到1.53 eV之間；在光電流密度量測中，以理論銦銅比例 (In/Cu ratio) 為1.84的 sample (f) 在含有S2-與SO32-水溶液中，以施加偏壓+0.4V (vs. Ag/AgCl)下，可得到最高光電流密度5.37 mA/cm2：穩定性測試中，以理論銦銅比例 (In/Cu ratio) 為1.84的sample (f) 於在含有S2-與SO32-水溶液中，以施加偏壓+0.4V (vs. Ag/AgCl) 下，有最佳的光穩定性。電性量測方面，薄膜的載子濃度介於3.29×1014~ 1.90×1020cm-3之間，理論銦銅比例≦1.02的參數所成長出來的薄膜為p型的導電型態，而理論銦銅比例>1.02的參數所成長出來的薄膜為n型的導電型態。其中理論銦銅比例為1.02的參數經EDAX分析後其比例最接近CuInS2理論比例1:1:2，由此可知本研究成功地經由控制金屬前驅物薄膜比例而達到控制薄膜的導電型態，製備出p-type及n-type的CuInS2薄膜。

In this study, CuInS2 ternary thin films were deposited on soda lime glass substrate using sulfrization of sequentially deposited indium/copper stacked layer using Radio frequency (RF) magnetron sputtering method. In order to control the composition of metal precursor films, the indium/copper ratios in samples were adjusted using various deposition time of copper and indium layers. The structural, composition, thickness, optical and electrical properties of the various indium/copper ratios in samples were investigated. According to energy dispersive analysis of X-ray (EDAX) results, indium/copper ratios in samples increased with an increase in theoretical indium/copper ratios in precursor films. According to X-ray diffraction patterns, the CuS phase was observed in copper rich samples (samples (a)、(b)), the In2S3 phase was observed in indium rich samples (samples (f)、(g)). The direct energy band gaps of samples were in the range of 1.39 - 1.53 eV, with increasing of the indium/copper ratio in films. The flat band potentials of samples were in the range of -0.32 to +0.14V (vs. normal hydrogen electrode, NHE) for p-type, and -0.68 to -0.76V for n-type (vs. NHE) using Mott-Schottky measurements and onset photocurrent-applied voltage plots respectively. Sample (c) had the best photoresponse for p-type films and sample (f) had the best photoresponse for n-type films in solution containing SO32- and S2- ion. The n to p transitional point of conduction type for samples in this study was the molar ratio of indium/copper in precursor films = 1.02. According to our study, it’s possible to control the conduction type of samples by adjusting the ratio of indium/copper molar ratios in the precursor films.

目錄
致謝 I
摘要 II
Abstract IV
目錄 VI
圖目錄 XI
表目錄 XV
第一章 緒論 1
1.1前言 1
1.2太陽能電池發展 3
1.3研究目的 4
第二章 文獻回顧與理論基礎 6
2.1半導體簡介 6
2.2半導體能帶理論 7
2.2.1. 電子能帶結構 7
2.2.2. 費米能階 8
2.2.3. 直接能隙和間接能隙 9
2.3光伏效應 10
2.4半導體光觸媒 11
2.4.1光觸媒 11
2.4.2半導體光觸媒水分解產氫原理 11
2.4.3半導體光觸媒光電化學行為 12
2.4.4常見的半導體光觸媒 13
2.5硫化銅銦 (CuInS2) 材料簡介 13
2.5.1晶體結構 13
2.5.2 化學組成與電性關係 14
2.6成長硫化銅銦 (CuInS2) 的方法 15
2.6.1噴霧熱裂解法 (spray pyrolysis) 15
2.6.2熱蒸鍍法 (thermal evaporation) 16
2.6.3分子束磊晶 (molecular beam epitaxy) 16
2.6.4化學水浴法 (chemical bath deposition) 17
2.6.5電沉積法 (electrodeposition) 17
2.6.6濺鍍法 (sputtering) 18
2.7濺鍍概論 18
2.7.1濺鍍原理 18
2.7.2直流濺鍍與射頻濺鍍 19
2.7.3磁控濺鍍 20
2.7.4濺鍍率 20
2.8濺鍍法製備CuInS2 21
第三章 實驗方法 36
3.1實驗材料 36
3.1.1實驗靶材 36
3.1.2實驗氣體 36
3.1.3基材 36
3.1.4實驗藥品 37
3.2實驗儀器設備 37
3.2.1薄膜製程設備 37
3.2.2分析儀器 38
3.3實驗流程 40
3.3.1基材準備及清洗 40
3.3.2銅、銦前驅物薄膜製備 41
3.3.3薄膜硫化 44
3.4薄膜性質分析 44
第四章 結果與討論 48
4.1 In/Cu前驅物薄膜製備及分析 48
4.1.1薄膜厚度及濺鍍率 48
4.1.2薄膜成份比分析 49
4.1.3晶型結構分析 50
4.2硫化溫度對CuInS2薄膜影響 50
4.3薄膜成分分析 52
4.3.1 EDAX成分分析 52
4.3.2 XPS分析 52
4.4晶型結構分析 54
4.5表面型態分析 54
4.6膜厚分析 55
4.7光學性質分析 56
4.7.1薄膜穿透率與反射率 56
4.7.2直接能隙計算 56
4.8薄膜電性分析 58
4.9光電化學性質量測 60
4.9.1交流阻抗分析 60
4.9.2 Mott-Schottky量測 63
4.9.3光電流密度量測 65
4.9.4薄膜穩定性量測 69
第五章 結論與未來展望 96
5.1結論 96
5.2未來展望 97
參考文獻 98










圖目錄
圖2-1 導體、半導體、絕緣體等固體材料之電導率(電阻率)範圍 23
圖2-2 電子能量對原子間距作圖 23
圖2-3 絕緣體、金屬、半金屬與半導體之能帶被電子佔據情形 24
圖2-4 半導體直接能隙 (a) 和間接能隙 (b) 能量與動量關係 24
圖2-5 光觸媒分解水原理示意圖 25
圖2-6 n型半導體及p型半導體在水溶液中能帶彎曲示意圖 25
圖2-7 常見光觸媒能帶結構圖 26
圖2-8 (a)閃鋅礦結構、(b)黃銅礦結構 26
圖2-9 Cu-In-S三元化合物化學組成缺陷概略圖 27
圖2 10 濺鍍現象示意圖 27
圖3 1 實驗設備簡圖 45
圖3 2 光電化學電池裝置 46
圖3-3 製備CuInS2薄膜實驗流程圖 47
圖4 1 不同In/Cu組成比例之金屬前驅物薄膜XRD圖 71
圖4 2 樣品 (c)理論成分比In/Cu=1.02，在不同硫化溫度下之XRD 圖 71
圖4 3 理論In/Cu成份比對EDAX分析之In/Cu成份比與2S/(Cu+3In) 作圖 72
圖 4 4樣品 (a) 理論成分比In/Cu=0.51，薄膜硫化後之XPS分析 72
圖 4 5樣品 (c) 理論成分比In/Cu=1.02，薄膜硫化後之XPS分析 73
圖 4 6樣品 (d) 理論成分比In/Cu=1.23，薄膜硫化後之XPS分析. 73
圖 4 7樣品 (g) 理論成分比In/Cu=2.05，薄膜硫化後之XPS分析. 74
圖 4 8不同In/Cu組成比例之金屬前驅物薄膜硫化後其XRD圖 74
圖 4 9樣品 (a)、(b) 理論成分比In/Cu=0.51及0.68之放大XRD圖 75
圖 4 10樣品 (a) In/Cu=0.48 (from EDAX) 之SEM圖 75
圖 4 11樣品 (b) In/Cu=0.57 (from EDAX) 之SEM圖 76
圖 4 12樣品 (c) In/Cu=0.83 (from EDAX) 之SEM圖 76
圖 4 13樣品 (d) In/Cu=0.99 (from EDAX) 之SEM圖 77
圖 4 14樣品 (e) In/Cu=1.05 (from EDAX) 之SEM圖 77
圖 4 15樣品 (f) In/Cu=1.11 (from EDAX) 之SEM圖 78
圖 4 16樣品 (g) In/Cu=1.22 (from EDAX) 之SEM圖 78
圖 4 17樣品 (a) In/Cu=0.48 (from EDAX) 之AFM圖 79
圖 4 18樣品 (b) In/Cu=0.57 (from EDAX) 之AFM圖 79
圖 4 19樣品 (c) In/Cu=0.83 (from EDAX) 之AFM圖 80
圖 4 20樣品 (d) In/Cu=0.99 (from EDAX) 之AFM圖 80
圖4 21樣品 (e) In/Cu=1.05 (from EDAX) 之AFM圖 81
圖4 22樣品 (f) In/Cu=1.11 (from EDAX) 之AFM圖 81
圖4 23樣品 (g) In/Cu=1.22 (from EDAX) 之AFM圖 82
圖4-24樣品 (a) ~ (g) In/Cu=0.48~1.22 (from EDAX) 之穿透光譜 82
圖4-25樣品 (a) ~ (g) In/Cu=0.48~1.22 (from EDAX)之反射光譜 83
圖4-26樣品 (a) ~ (g) In/Cu=0.48~1.22 (from EDAX) 之 (αhv)2 vs. hv 83
圖4-27薄膜內In/Cu成份比對能隙的影響 84
圖4-28薄膜內In/Cu成份比對樣品載子濃度及遷移率的影響 84
圖4-29樣品 (a) ~ (d)，In/Cu=0.48~0.99 (from EDAX)之交流阻抗分 析 85
圖4 30樣品 (e) ~ (g) In/Cu=1.05~1.22 (from EDAX)之交流阻抗分析 85
圖4 31樣品(a) ~ (d)，In/Cu=0.48~0.99 (from EDAX)之Mott-Schottky量測 86
圖4 32樣品(e) ~ (g)，In/Cu=1.05~1.22 (from EDAX)之Mott-Schottky量測 86
圖4-33樣品(a) ~ (g)，In/Cu=0.48~1.22 (from EDAX)之能帶結構圖. 87
圖4-34樣品 (a) ~ (d)，In/Cu=0.48 ~ 0.99 (from EDAX)於K2SO4溶液之電流密度對電壓變化圖 87
圖4-35樣品 (e) ~ (g)，In/Cu=1.05~1.22 (from EDAX)於K2SO4溶液之電流密度對電壓變化圖 88
圖4 36樣品 (c)，In/Cu=0.83 (from EDAX)於含有SO32-/S2-離子水溶液之電流密度對電壓變化圖 88
圖4-37樣品 (f)，In/Cu=1.11 (from EDAX)於含有SO32-/S2-離子水溶液之電流密度對電壓變化圖 89
圖4 38樣品 (c)，In/Cu=0.83 (from EDAX)於K2SO4水溶液中之I-t 圖 89
圖4 39 樣品 (f)，In/Cu=1.11 (from EDAX)於K2SO4水溶液中之I-t 圖 90
圖4 40 樣品 (c)，In/Cu=0.83 (from EDAX) 於含有SO32-/S2-離子水溶液中之I-t 圖 90
圖4 41樣品 (f)，In/Cu=1.11 (from EDAX)於含有SO32-/S2-離子水溶液中之I-t 圖 91


表目錄
表2 1一般CuInS2的電阻率(ρ)、載子濃度(n,p)及載子遷移率(μ)範圍 28
表2 2以不同方法製備CuInS2 薄膜 29
表2 3濺鍍法製備CuInS2薄膜文獻回顧 34
表4-1本製程中不同靶材的濺鍍率 92
表4 2樣品 (a) ~ (g) 的製程參數 92
表4 3薄膜理論成份比及其EDAX組成分析 93
表4-4不同In/Cu成分比之前驅物薄膜硫化後的EDAX組成分析 93
表4-5樣品 (a) ~ (g) 霍爾效應量测所得之結果 94
表4-6利用濺鍍法成長CuInS2半導體薄膜於K2SO4水溶液之物理性 質 95

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