臺灣博碩士論文加值系統

在本篇論文中，先在ITO玻璃上旋轉塗佈不同氧化鋅晶種層，再利用低溫水熱法成長氧化鋅奈米柱結構，並且製成太陽能電池，希望利用奈米柱結構所增加的表面積，來增加太陽能電池的照光面積，進而提升太陽能電池效率。在不同奈米柱結構上，利用高頻(40.68 MHz)電漿輔助化學氣相沉積系統，沉積p型氫化非晶矽(p-layer)、本質氫化非晶矽(i-layer)以及n型氫化非晶矽薄膜(n-layer)，再利用熱蒸鍍機鍍上鋁電極，製作成太陽能電池，經由I-V量測結果所萃取的電性參數做討論與分析。

因為晶種層會影響氧化鋅奈米柱的成長，一般而言是利用熱退火改變晶種層，熱退火會讓晶種表面排列整齊，使得長出來的奈米柱品質比較好。為了能調變奈米柱的密度大小，探討不同晶種層對所成長奈米柱的影響，於是改變晶種層塗佈次數、鹽酸蝕刻晶種層的時間以及氫電漿轟擊晶種層的時間，所得的晶種層經由SEM檢測其表面和橫截面形貌並估算其厚度。

鹽酸蝕刻後的晶種層，使得能成長氧化鋅奈米柱的晶種變少，可以有效減少奈米柱的密度；氫電漿轟擊則會蝕刻和鈍化晶種層，也能得到奈米柱密度。使用不同晶種層結構和固定水熱法條件所成長不同的氧化鋅奈米柱，並且改變水熱法成長時間所得到的奈米柱，經由SEM觀察其形貌及結構，討論其成長機制並估算長度、密度和直徑。

利用不同晶種層所成長奈米柱結構，經由UV-VIS量測其穿透率，探討不同奈米柱結構對穿透率的關係。奈米柱的穿透率愈大，可以有效提升太陽能電池的短路電流。雖然太陽能電池的效率不高，但經由鹽酸蝕刻和氫電漿轟擊晶種層，能有效地調變奈米柱的密度，藉此改善了太陽能電池效率8.8 %。

In this study, the different seed layers of ZnO were coated by spin technique on the ITO glass, and the ZnO nanorods grew through the low-temperature hydrothermal method. Finally, they were used in the solar cells. We hoped to increase the surface area by nanorods structure, resulted in the increment of illuminated area and the enhancement of efficiency for the solar cells. Thin film solar cells were fabricated by the high frequency (40.68 MHz) plasma enhanced chemical vaper deposition system (PECVD), depositing the p-type α-Si:H, intrinsic of α-Si:H and n-type α-Si:H films, and the Al electrode was formed by thermal evaporator. The electrical parameters of solar cells were extracted from the I-V measurement to comepare the effects of different seed layers.

The seed layers would affect the growth of ZnO nanorods. We usually used the annealing process to change the seed layers structure and seed surface morphology, resulted in better quality of ZnO nanorods. In order to obtain the lower ZnO nanorod density, the different spin coating times, diluted HCl etching time and hydrogen plasma treatment time were performed on the seed layers. The top and cross-sectional views of seed layers were observed with SEM, to estimate the thickness of seed layers and to discuss the structure variation of seed layers.

The seed layers etched by the diluted HCl could effectively reduce the density of ZnO nanorods due to the less seeds removed by the HCl solution. Hydrogen plasma treatment not only etched but also passivated the seed layers, resulted in the less ZnO nanorod density. The different ZnO nanorods were grown via different seed layer structure under the same hydrothermal condition. The morphology and structure of ZnO nanorods were observed by SEM, to discuss the growing mechanism and to estimate their length, density and diameter.

The transmittance of nanorods was measured with UV-VIS, which was used to investigate the relationship of the different ZnO nanorods structure and transmittance. The larger the transmittance of ZnO nanorod is the greater the short-circuit current density of the solar cell. The diluted HCl etching and hydrogen plasma treatment would effectively achieve the modulation of ZnO nanorods density. Therefore, the efficiency of solar cell could be improved about 8.8 %.

目錄

誌謝 i
摘要 ii
Abstract iii
目錄 v
圖目錄 vii
表目錄 ix
第一章 簡介 1
1.1 前言 1
1.2 動機與目的 3
1.3 文獻探討 4
1.4 論文架構 5
第二章 氧化鋅奈米柱和太陽能電池 6
2.1 氧化鋅性質與特性 6
2.2 氧化鋅奈米微結構 9
2.3 氧化鋅薄膜成膜的原理和方法 11
2.3.1溶膠-凝膠法 (Sol-Gel) 11
2.3.2旋轉塗佈法 (Spin coating) 13
2.4 氧化鋅奈米柱成長機制 13
2.5 不同晶種層對氧化鋅奈米柱的影響 16
2.6 太陽能電池基本原理 18
2.7 太陽能電池的參數 21
第三章 實驗方法、流程及實驗機台介紹 26
3.1 實驗所需的化學藥品 26
3.2 氧化鋅晶種層製作 27
3.2.1清洗ITO玻璃 27
3.2.2調配晶種溶液 27
3.2.3旋轉塗佈流程 28
3.2.4晶種層處理 29
3.3 水熱法成長氧化鋅奈米柱 30
3.3.1水熱法流程 30
3.3.2成長氧化鋅奈米柱流程 31
3.4 太陽能電池製作流程 32
3.5 高溫爐管 33
3.6 FE-SEM場發射掃描式電子顯微鏡 34
3.7 高頻電漿輔助化學氣相沉積系統 36
3.8 熱蒸鍍機 38
第四章 結果與討論 39
4.1 不同晶種層對氧化鋅奈米柱的結構探討 39
4.1.1不同塗佈次數的晶種層對氧化鋅奈米柱的影響 39
4.1.2不同水熱法成長時間對氧化鋅奈米柱的影響 45
4.1.3鹽酸蝕刻晶種層對氧化鋅奈米柱的影響 48
4.1.4氫電漿轟擊晶種層對氧化鋅奈米柱的影響 53
4.2 氧化鋅奈米柱結構對太陽能電池特性影響 58
4.2.1鹽酸蝕刻晶種層的奈米柱對太陽能電池的影響 58
4.2.2氫電漿轟擊晶種層的奈米柱對太陽能電池的影響 61
第五章 結論 64
參考文獻 65

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