臺灣博碩士論文加值系統

本研究係以射頻矽甲烷電漿輔助化學氣相沉積系統，藉由調配適當的反應參數如基材溫度、反應壓力及甲烷摻雜比等，分別進行本質非晶矽及p型非晶碳化矽薄膜之沉積，並針對薄膜的結構及光電性質加以分析，以設計出非晶矽薄膜太陽能電池元件的最適化製程。
實驗結果顯示，當控制基材溫度為170oC、反應壓力為200 mTorr時，所沉積的非晶矽薄膜之光學能隙為1.75 eV；在電性表現方面，其暗導電率為7.97×10-10 S/cm，且光敏感程度達3.49×104。
另一方面，針對p型非晶碳化矽薄膜的製備，藉由通入甲烷至矽甲烷電漿形成寬能隙的非晶碳化矽薄膜將有效提升薄膜的光學性質，當甲烷對矽甲烷流量比為0.5時，所成長的p型非晶碳化矽薄膜的暗導電率為2.36×10-7 S/cm，且光學能隙可達到2.01 eV，其電性及光學性質適宜作為非晶矽薄膜太陽能電池元件窗口層的應用。
最後，利用多重腔體連結式PECVD裝置製作單層接面非晶矽薄膜太陽能電池，現階段所得最佳元件之開路電壓、短路電流及填充係數分為828 mV、14.56 mA/cm2及64.95 %，光電轉換效率達7.83 %。

In this thesis, the intrinsic hydrogenated amorphous silicon (a-Si:H) thin films and p-type hydrogenated amorphous silicon carbide (a-SiC:H) thin film were deposited on glass by radio-frequency silane plasma enhanced chemical vapor deposition system. The thin films were prepared under different experimental parameters, such as substrate temperature, reaction pressure and methane flow ratio. For optimization of the layer, the dependence of electrical and optical properties were investigated.
In the first part, we deposited intrinsic a-Si:H by altering the deposition condition. We set up the substrate temperature at 170oC and reaction pressure at 200 mTorr, the optical band gap of the film deposited was 1.75 eV. The dark conductivity and photosensitivity were 7.97×10-10 S/cm and 3.49×104, respectively.
In the second part, we deposited p-type a-SiC:H with silane and methane. The dark conductivity and optical gap of the film deposited at [CH4]/[SiH4] = 0.5 were 2.36×10-7 S/cm and 2.01 eV, respectively. The result showed that the films were more transparent than amorphous silicon.
Finally, we deposited amorphous silicon thin film solar cell. The short-circuit current(Jsc), open-circuit voltage(Voc) and fill factor(FF) of device were 14.56 mA/cm2, 828 mV and 64.95 %, respectively. The optoelectronic conversion efficiency of 7.83 % was achieved.

摘要 I
Abstract II
誌 謝 III
目 錄 V
圖 索 引 VIII
表 索 引 XIV
第一章 緒論 1
1.1 前言 1
1.2 研究動機與目的 3
第二章 理論基礎與文獻回顧 4
2.1非晶矽薄膜 4
2.1.1非晶矽的原子結構及其基本特性 4
2.1.2非晶矽的能帶結構 7
2.1.3非晶矽薄膜的摻雜 10
2.1.4非晶矽薄膜的光致衰退現象 11
2.2 以電漿輔助化學氣相沉積法製備非晶矽薄膜 13
2.2.1射頻電漿輔助化學氣相沉積法 13
2.2.2矽甲烷電漿分解程序 14
2.2.3非晶矽薄膜成長機制 17
2.3 非晶矽薄膜隙態密度與光吸收邊緣曲線之關係 19
2.4 矽氫鍵結對非晶矽薄膜的影響 22
2.5 懸鍵缺陷及弱鍵分布情形對非晶矽薄膜的影響 25
2.6 非晶碳化矽薄膜 26
2.7 非晶矽薄膜太陽能電池元件結構及光電轉換原理 27
2.7.1非晶矽薄膜太陽能電池元件結構 27
2.7.2非晶矽薄膜太陽能電池光電轉換原理 30
第三章 實驗方法與步驟 31
3.1實驗流程圖 31
3.2 實驗藥品及氣體 32
3.3 實驗裝置 35
3.4 分析儀器 37
3.4.1表面形態輪廓儀 (surface profiler) 37
3.4.2拉曼光譜儀 (Raman) 38
3.4.3傅立葉紅外線光譜儀 (FTIR) 39
3.4.4紫外光/可見光光譜儀 (UV/VIS) 40
3.4.5 X射線電子能譜化學分析儀 (XPS) 43
3.4.6 IV量測系統 (IV) 44
3.4.7太陽光模擬器 (solar simulator) 46
3.4.8分光效率量測儀 (IPCE) 50
3.5 實驗步驟 51
3.5.1玻璃基材清洗 51
3.5.2成長非晶矽薄膜及非晶碳化矽薄膜 52
3.5.3成長非晶矽薄膜太陽能電池元件 53
第四章 實驗結果與討論 54
4.1 成長本質非晶矽薄膜 54
4.1.1 基材溫度對非晶矽薄膜的影響 54
4.1.2 反應壓力對非晶矽薄膜的影響 69
4.2 成長p型非晶碳化矽薄膜 85
4.3 非晶矽薄膜太陽能電池 98
4.3.1吸收層沉積條件對太陽能電池元件的影響 98
4.3.2窗口層沉積條件對太陽能電池元件的影響 105
第五章 結論 113
參考文獻 116
作者簡介 125

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