本研究的主要焦點是通過鎳薄膜成核形成遮罩和RIE（反應離子刻蝕）在太陽能電池中的應用，在多晶矽晶片上製造奈米仿生欄柵結構。奈米仿生欄柵結構在波長範圍500nm至1000nm內有最低的反射率為2％，在400nm到1050nm的波長範圍內，反射率是在4％以下。另外增加消除RIE損傷的製程，使用HNO3/HF/H2O的混和液蝕刻和高溫退火，藉以提高少數載子的壽命時間。我們量測少數載子的壽命時間在RIE製程後和消除RIE損傷製程後，發現少數載子的壽命時間從1.43us增加至29.25us時間。優於平整沒有結構的少數載子的壽命時間3.77us。
最後，我們在製作奈米仿生光柵結構後，繼續後續製程擴散、沉積抗反射鈍化層、網印和燒結完成太陽能電池，我們實現了9.26％的效率，短路電流（Jsc）為30mA/cm2，開路電壓（Voc）為0.53V，填充因子（FF）為0.53。



關鍵字:多晶矽、太陽能電池、欄柵、次波長

This study focus on the fabrication of nano bionic grating structures in polycrystalline silicon wafer by nucleation of nickel thin film and RIE(reactive ion etching) for solar cell application. The lowest reflection of nano bionic grating structures obtained was 2% in the range of wavelength from 500nm to 1000nm and from 400nm to 1050nm wavelength range, the reflection was below 4%. Extra damage elimination processes using HNO3/HF/H2O and high temperature anneal were carried out in addition to the process flow to enhance the carrier life time. We measured the life time after RIE and damage elimination processes and life time enhanced from 1.43us to 29.25us.
Finally, we fabricated poly-Si solar cell with nano bionic grating structures after the process steps such as doping, anti-reflective, passivation coating deposition, screen printer electrode, and co-fired and we achieved an efficiency of 9.26% with a short circuit current (Jsc) of 30mA/cm2, open circuit (Voc) of 0.53V, and fill factor (FF) of 0.53. Key word: Solar, Poly, Grating, Sub-wavelength

contents
Chapter 1 1
Introduction 1
1.1 Solar Energy 1
1.2 Introduction:The history of the solar cell 2
1.3 Solar cell Fundamentals 4
1.4 The Physical of the Solar Cell 7
Chapter 2 11
Solar Cell Operation 11
2.1 Solar Cell Structure 11
2.2 The Current and Voltage Characteristic 12
2.3 Short-Circuit Current 14
2.4 Open Circuit Voltage 16
2.5 Fill Factor 17
2.6 Efficiency 18
2.7 Electrical Losses 19
Chapter 3 21
Experimental process and Equipments 21
3.1 Fabrication Processes 21
3.1.1 Process flow 21
3.1.2 Formation of nano bionic grating structures 24
3.2 Experimental Techniques 28
3.2.1 RIE system 28
3.2.2 E-Gun system 29
3.3 Characterization Tools 30
3.3.1 Scanning Electron Microscope (SEM) 30
3.3.2 Spreading Resistance Probe System (SRP) 33
3.3.3 Solar simulator 35
3.3.4 Quantum efficiency (QE) 36
3.3.5 Lifetime-measurement system and theory 37
Chapter 4 39
Result and discussions 39
4.1 Nano bionic grating structure 39
4.2 Reflectance measurement 57
4.3 RIE damage Removal 60
4.4 BSF analysis 64
4.5 Photo current-voltage analysis 68
Chapter 5 71
Conclusions and Future work 71
References： 73

[1] G.P. Willeke, “Thin crystalline silicon solar cells”, solar energy materials & solar cells, p.191-200,(2002).
[2] K. Adolf M¨unzer, Konstantin T. Holdermann, Reinhold E. Schlosser, “Thin monocrystalline silicon solar cells”, IEEE Transactions on electron devices, Vol. 46, No. 10, October 1999.
[3] Arnulf Jäger-Waldau, “Status of pv research, solar cell production and market implementation in japan, usa and the european union” European Commission Joint Research Centre; Renewable Energies Unit Ispra, September 2002.
[4] 蔡進譯,“超高效率太陽電池-從愛因斯坦光電效應談起”, 物理雙月刊27卷5期
[5] Cheng-Wen Lin, “Optimization of front contact patterns for commercialized multi-crystalline silicon solar cells”, National Cheng Kung University Master Thesis (2007)
[6] Photovoltaics CDROM Christiana Honsberg and Stuart Bowden
(http://pvcdrom.pveducation.org/index.html)
[7] 黃惠良,太陽能電池Chapter2, p.116~119 ,五南圖書出版公司 (2008)

[8] Jun-Yan Hwang, “The study of passivation effects on the modified granting solar cell by the Al2O3/TEOS deposition Process”, NTHU Master Thesis (2010)

[9] Softpedia
(http://news.softpedia.com/news/Moth-Eyes-and-Cicada-Wings-For-the-Solar-Cells-and-Windows-of-the-Future-69089.shtml)
(2009)
[10] NDL ILD-4100金屬乾式蝕刻機儀器簡介
[11] NDL E-gun 設備標準作業程序
[12] James D. Plummer, Michael D. Deal, and Peter B. Griffin, Silicon VLSI Technology, Chapter4, p.174-175, Prentice Hall (2000)
[13] Jeong KIM, In Sik MOON, Moon Jae LEE and Dae Won KIM, Journal of the Ceramic Society of Japan 115 [5] 333-337 (2007)
[14] Sciencetech http://0rz.tw/6a48z
Serving The Optical Spectroscopy Community For Over 23 Years (1985~2008)
[15] http://www.newport.com/
[16] Sinton R.A, Cuevas, A., Appl. Phys.Lett 69 (1996)
[17] Sebastian Schaeferaand Ralf Lu¨demann, “Low damage reactive ion etching for photovoltaic applications”American Vacuum Society. [S0734-2101(99)00803-9] 1999
[18] S.H. Cheng, “The passivation effect of NAOS/TEOS treatment on honeycomb structure crystalline silicon solar cell”, NTHU master Thesis (2012)
[19] C.H. Chen, “Investigations on Novel Surface Structures for High Efficiency Crystalline Silicon Solar Cells”, NTHU doctor Thesis (2011)