臺灣博碩士論文加值系統

本研究旨在利用熱燈絲化學氣相沉積技術製作碳化矽薄膜並應用於薄膜太陽電池吸光層。透過控制碳化矽沉積時的矽甲烷、甲烷及氫稀釋比例，探討不同製程條件相對的薄膜光電特性與結構變化，並優化製程條件使產出元件等級之碳化矽薄膜，最後實際製作成薄膜太陽電池以驗證此薄膜的品質。薄膜分析部分使用了化學分析電子能譜儀、傅立葉轉換紅外線光譜儀來探討Si-C成份的化學鍵結；以X光繞射儀、拉曼光譜儀鑑定薄膜的晶體結構；以場發射電子顯微鏡觀察其表面形貌；並分析薄膜的光暗電導特性與光學性質，探討各參數對薄膜品質之影響。在本研究中，透過材料分析與製程條件之修改，當矽甲烷、甲烷比例為1：1時，可以得到較佳的本質碳化矽薄膜，此時薄膜之光學能隙為1.98eV，光電導/暗電導的比值約在103左右。元件製作部分使用ITO玻璃作為基材，以單一腔體之熱燈絲化學氣相沉積系統連續製作p型碳化矽、本質碳化矽與n型微晶矽薄膜，形成pin薄膜太陽電池結構，最後再以電子束蒸鍍系統鍍上金屬背電極，此碳化矽薄膜太陽電池效率達=2.44 %，未來持續改善製程條件進而應用於串接式結構。

In this thesis, silicon carbide (SiC) thin films prepared by hot-wire chemical vapor deposition (HWCVD) system was investigated for absorption layer of thin-film solar cells applications. During the deposition, the gas flow rate ratios of SiH4 and CH4 and H2 dilution were varied to study the effects of process conditions on the optoelectronic characteristics and microstructures of SiC thin films. The optimized process conditions of SiC thin film deposition were used to fabricate thin film solar cells. Details of material characteristics of SiC thin films were investigated in terms of x-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectrometer, x-ray diffraction (XRD), Raman spectroscopy, and field-emission scanning electron microscopy (FESEM). Electrical properties of SiC thin films were determined by I-V measurement under AM1.5. The optimum deposition conditions of SiC thin film were SiH4/CH4 ratio of 1 and without H2 dilution. The optical bandgap and ratio of photo- and dark-conductivity of SiC thin film were 1.98 eV and 1000, respectively. In thin film solar cell fabrication, p-type SiC, intrinsic SiC, and n-type microcrystalline Si thin films were prepared on ITO glass substrates by HWCVD system. Al back-electrode was used and prepared by electron-beam evaporation. The efficiency of SiC thin film solar cells was 2.44 %. The further improvement of process conditions on SiC thin film could be performed for tandem solar cells.

目錄
封面內頁
簽名頁
授權書
中文摘要i
Abstract ii
誌謝iii
目錄iv
表目錄vii
圖目錄viii
第一章 緒論1
1-1 前言1
1-2 矽薄膜太陽電池發展1
1-3 研究動機與目的3
1-4 論文架構3
第二章 理論基礎與文獻回顧4
2-1 太陽電池發電原理4
2-2 太陽電池等效電路與效率計算5
2-3 碳化矽文獻回顧6
2-4 熱燈絲化學氣相沉積法 7
2-4-1 熱燈絲化學氣相沉積法文獻回顧7
2-4-2 熱燈絲化學氣相沉積法之原理8
2-4-3 熱燈絲化學氣相沉積法沉積矽薄膜的反應機制8
2-4-4 熱燈絲化學氣相沉積法之優點9
第三章 實驗步驟與研究方法10
3-1 實驗參數規劃與實驗步驟流程10
3-1-1 實驗材料及基材前處理11
3-2 實驗設備12
3-2-1 熱燈絲化學氣相沈積系統12
3-2-2 電子束蒸鍍機13
3-2-3 感應式耦合反應蝕刻系統14
3-3 薄膜分析的方法14
3-3-1 表面輪廓儀(α-Step)14
3-3-2 X光繞射儀(X-ray Diffraction，XRD)14
3-3-3 拉曼光譜儀(Raman Spectrometer)15
3-3-4 傅立葉轉換紅外線光譜儀(FTIR)16
3-3-5 化學分析電子能譜儀(XPS)16
3-3-6 場發射電子顯微鏡(FE-SEM)17
3-3-7 薄膜特性分析儀(N&K Analyzer)17
3-3-8 霍爾效應量測(Hall Measurement)17
3-3-9 光暗電導及效率量測18
第四章 結果與討論 19
4-1 本質碳化矽薄膜厚度與鍍率分析19
4-2 本質碳化矽薄膜材料分析 20
4-2-1 薄膜晶體結構與結晶性分析20
4-2-2 薄膜之微結構分析21
4-2-3 薄膜之傅立葉轉換紅外線光譜儀分析23
4-2-4 薄膜之化學分析電子能譜儀分析24
4-3 本質碳化矽薄膜光學性質分析25
4-4 本質碳化矽薄膜電性分析 26
4-5 p、n層膜特性之分析27
4-5-1 p 層膜沉積條件與特性分析27
4-5-2 n 層膜沉積條件與特性分析28
4-6 太陽電池製作及其特性28
第五章 結論30
參考文獻32

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