低成本、高效率的製程技術一直是太陽電池最重要的議題。在光吸收層之選擇上，直接能隙的I-III-VI族化合物半導體材料硒化銅銦鎵，藉由調變本身的組成比例具有1.1到1.7 eV的能隙，在太陽光譜中涵蓋有非常高的光電轉換效率，是作為薄膜型太陽能電池極為被看好且深具發展潛力的主吸收層材料。硒化銅銦鎵屬於直接能隙的半導體材料且具有非常高的光吸收係數，所需的厚度相較於其他材料而言可以較薄，故可以降低生長成本。本實驗採用濺鍍法製備銅銦鎵合金層，再配合硒化技術形成硒化銅銦鎵，針對不同的銅銦鎵濺鍍參數與硒化條件對於改善硒化銅銦鎵薄膜之品質及特性進行研究與探討。

Low-cost and high-efficiency are of continuous interest for the fabrication of solar cells. I-III-VI compound semiconductors Cu(In,Ga)Se2 (CIGS) are the most important absorber materials in developing thin film solar cells. The bandgap of CIGS varies from about 1.1 to 1.7 eV, which is within the maximum solar absorption region. This is very important for the optimum conversion efficiency. The extraordinarily high absorption coefficient from direct bandgap leads to thinner thickness and lower fabrication cost for its use in thin film solar cells. In this experiment, we deposit CuInGa alloy layer on Mo-coated soda-lime glass by RF sputtering and then use selenization process to form Cu(In,Ga)Se2. We study the characterization of sputtered CIG alloy layer and selenized CIGS thin film.

致謝 i
ACKNOWLEDGEMENT iii
摘要 iv
ABSTRACT v
CONTENTS vi
LIST OF FIGURES viii
LIST OF TABLES xii
Chapter 1 1
Introduction 1
1.1 Solar Cells 1
1.2 Solar Spectrum and Air Mass 2
1.3 Solar cell equivalent circuit 4
1.4 CIGS thin-film solar cell 7
1.4.1 Characterization of CIGS thin-film solar cell 7
1.4.2 Structure of CIGS solar cell 8
1.5 Motivation 11
Chapter 2 16
Experimental 16
2.1 Preparation of soda-lime glass substrates 16
2.2 Sputtering of Mo back contact 16
2.3 Deposition of Cu-In-Ga alloy layer by RF sputtering 16
2.4 Selenization of Cu-In-Ga alloy layer 17
2.5 Measurements 17
Chapter 3 21
Results and Discussion 21
3.1 Dependence of CIG characteristics on sputtering parameters 21
3.1.1 Dependence of CIG characteristics on sputtering time 21
3.1.2 Dependence of CIG characteristics on sputtering power 22
3.2 Dependence of CIGS characteristics on selenization parameters 23
3.2.1 Dependence of CIGS characteristics on selenization temperature 23
3.2.2 Dependence of CIGS characteristics on selenization time 26
3.2.3 Dependence of CIGS characteristics on selenization gas flow 27
Chapter 4 51
Conclusion 51
References 53

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