本實驗室致力於改善太陽能電池的鈍化層，近年來太陽能電池又隨著種種議題回到眾人的討論，而在這之中，如何以最低成本製作高效的太陽能電池是一件非常值得探討的議題，而本實驗為製作PERC太陽能電池。我們會以溶液塗佈與臭氧的方式形成鈍化層。使用濕式製程製作來降低成本，並利用臭氧氧化能力極強的特性形成較為緻密的鈍化層。
　　首先，我們使用P型矽基板來製作。我們將會探討氯化鋁與矽酸根溶液塗佈在基板背面形成三氧化二鋁作為鈍化層，在塗佈溶液後，我們會使用臭氧氧化，此後進行退火。我們會找出此溶液最佳的濃度、退火溫度與退火時間。在後續進行完退火後，為了觀察氧化鋁薄膜的特性，使用EDS、TEM量測來看成分的組成以及結構。我們使用最佳的參數為，氯化鋁比水的體積百分濃度100ml:0.5ml，矽酸根的體積百分濃度100ml:1ml，並將0.5ml的矽酸根加入50ml的氯化鋁溶液中，氧化時間20分鐘，退火時間15分鐘，退火溫度為500℃。得出的PERC太陽能電池，其最佳填充因子為75.6%、轉換效率為16.917%，比全面鋁的太陽能電池相比提升了0.522%。

　　Our lab is dedicated to finding a cost-effective way of depositing passivation layers for crystalline silicon solar cells. In recent years, solar cell have returned to human’s attention with various issues to be discussed. However, the issue of how to fabricate low cost and high-efficiency solar cells is always an important one. In this experiment, we develop a new passivation layer formula that is used for passivating the back surfaces of PERC solar cells. Our passivation layer is formed by using a wet chemical process and ozone oxidation. In this wet chemical process with post ozone oxidation, an AlOx layer is believed to be formed on the back surfaces of solar cells and good passivation effect is achieved.
　　In this study, p-type single crystalline silicon wafers were used. We discussed about the deposition process of forming Al2O3 films on rear sides of the wafers as passivation layers by using AlCl3/SiO32- solution. After coating the chemical solution, we then used ozone oxidation followed by an annealing process. The best concentration of the chemical solution,annealing temperature and annealing time period were discussed in this study. Measurements with EDS and TEM facilities were used to observe the elemental composition and the film structure. The best process parameters were found as follows. The volume percentage concentration of AlCl3 and water was 100ml:0.5ml; the volume percentage concentration of silicate solution was 100ml:1ml. 0.5ml of the prepared silicate solution is added into 50ml of the prepared AlCl3 solution. After coating the AlCl3/SiO32- solution, we performed 20-minute ozone oxidation, followed by 15-minute annealing at 500℃. The best PERC solar cell fabricated with this type of passivation layer had a fill factor of 75.6% and a conversion efficiency of 16.917%, the latter of which is 0.522% absolute higher than the best Al-BSF solar cell fabricated in the study.

第一章 導論 1
1.1前言 1
1.2文獻回顧 1
1.3研究目的與動機 6
1.4論文架構 6
第二章 研究方法與規劃 7
2.1實驗架構與元件製作流程 7
2.2實驗步驟 10
2.2.1 RCA Clean 10
2.2.2 表面粗糙化(Texture) 11
2.2.3 磷擴散(Phosphorous Diffusion) 12
2.2.4 晶邊絕緣(Edge Isolation) 12
2.2.5 氧化鋁膜製程 12
2.2.6 退火(Annealing) 13
2.2.7 氮化矽保護層(SiNx) 13
2.2.8 黃光製程(Photo Lithography) 13
2.2.9 抗反射層沉積(Deposit Anti-Reflection Coating，ARC) 15
2.2.10 網印電極(Screen Printing) 15
2.2.11 共燒結(Co-Firing) 17
2.3儀器介紹 18
第三章 實驗數據討論 21
3.1濕式製程氧化鋁薄膜材料之少數載子壽命 21
3.1.1不同比例混合溶液對於濕式製程氧化鋁的影響 21
3.1.2 臭氧氧化時間對於濕式製程氧化鋁的影響 28
3.1.3濕式製程氧化鋁薄膜之退火溫度與時間的影響 34
3.1.4 少數載子生命週期之衰退 56
3.1.5 SiNx與鈍化層相關之參數 60
3.2 TEM量測 62
3.3 反射率量測 65
3.4 C-V量測 66
3.5 元件轉換效率量測 67
3.6 Suns-Voc量測 69
3.7 外部量子效應量測 73
第四章 總結 74
第五章 參考文獻 76

[1]S. Mack, “Silicon surface passivation by thin thermal oxide/PECVD layer stack systems”, IEEE Journal of Photovoltaics, vol. 1, no. 2, pp. 135-145, 2011.
[2]F. Bellenger, “Passivation of Ge ( 100 ) ∕ GeO2 ∕ high-κ gate stacks using thermal oxide treatments”, Journal of the Electrochemical Society , vol. 155, no. 2, pp.33~38, 2008.
[3]P. Saint-Cast, “High-efficiency c-Si solar cells passivated with ALD and PECVD aluminum oxide”, IEEE Electron Device Letters, vol. 31, no. 7, pp. 695-697, 2010.
[4]S. Zhao, Q. Qiao, S. Zhang, J. Ji, Z. Shi, and G. Li, “Rear passivation of commercial multi-crystalline PERC solar cell by PECVD Al2O3”, Applied Surface Science, vol. 290, no. 0169-4332, pp. 66-70,2014.
[5]M. Y. Seo, E. N. Cho, C. E. Kim, P. Moon, and I. Yun, “Characterization of Al2O3 films grown by electron beam evaporator on Si substrates”, 2010 3rd International Nanoelectronics Conference (INEC), pp. 238-239, 2010.
[6]P. K. Liu, Y. L. Cheng, and L. K. Wang, “Crystalline silicon PERC solar cell with ozonized AlOx passivation layer on the rear side”, International Journal of Photoenergy, vol. 2020, article 6686797, 6 pages, 2020.
[7]B. Veith, T. Dullweber, M. Siebert, C. Kranz, F. Werner, N. P. Harder, J. Schmidt, B. F. P. Roos, T. Dippell, and R. Brendel, “Comparison of ICP-AlOx and ALD-Al2O3 layers for the rear surface passivation of c-Si solar cells”, Energy Procedia, vol. 27, no. 1876-6102, pp. 379-384, 2012.
[8]K. Ogutman, N. Iqbal, G. Gregory, M. Li, M. Haslinger, E. Cornagliotti, W. V. Schoenfeld, J. John, and K. O. Davis, “Spatial atomic layer deposition of aluminum oxide as a passivating hole contact for silicon solar cells”, Physica Status Solidi A, vol. 217, no. 18, 2020.
[9]D. M. Chapin , C. S. Fller, and G. L. Pearson, “A new silicon P-N junction photocell for converting solar radiation into electrical power”, Journal of Applied Physics, vol. 25, pp.676-677, 1954.
[10]PGE太平洋綠能, “ 2021太陽能趨勢”, Retrieved from https://blog.pgesolar.com.tw/2021/02/08/%E5%A4%AA%E9%99%BD%E8%83%BD%E8%B6%A8%E5%8B%A2
[11]OFweek太陽能光伏網, “主流太陽能電池優劣分析”, Retrieved from https://solar.ofweek.com/2021-01/ART-260006-8140-30481586.html
[12]NERL Transforming Energy, “Best Research-Cell Efficiency Chart”, Retrieved from https://www.nrel.gov/pv/cell-efficiency.html
[13]Solar Frontier, “Solar Frontier Achieves World Record Thin-Film Solar Cell Efficiency of 23.35%”, Retrieved from
https://www.solar-frontier.com/eng/news/2019/0117_press
[14]J. F. Geisz, R. M. France, and K. L. Schulte, “Six-junction III-V solar cells with 47.1% conversion efficiency under 143 suns concentration”, Nature Energy, vol. 5,no. 4, pp. 326-335, 2020.
[15]S. Schäfer and R. Brendel, “Accurate calculation of the absorptance enhances efficiency limit of crystalline silicon solar cells with lambertian light trapping”, IEEE Journal of Photovoltaics, vol. 8, no. 4, pp.1156-1158, 2018.
[16]P. Vitanov, E. Goranova, V. Stavrov, P. Ivanov, and P.K. Singh, “Fabrication of buried contact silicon solar cells using porous silicon”, Solar Energy Materials and Solar Cells, vol. 93, no. 3, pp.297-300, 2009.
[17]J. Benick, “High efficiency n-type PERT and PERL solar cells”, IEEE 40th Photovoltaic Specialist Conference (PVSC), pp. 3637-3640, 2014.
[18]T. Mishima, M. Taguchi, H. Sakata, and E. Maruyama, “Development status of high-efficiency HIT solar cells”, Solar Energy Materials and Solar Cells, vol. 95, no. 1, pp. 18-21, 2011.
[19]S. Kluska, F. Granek, M. Rüdiger, M. Hermle, and S. W. Glunz, “Modeling and optimization study of industrial n-type high-efficiency back contact back-junction silicon solar cells”, Solar Energy Materials and Solar Cells, vol. 94, no. 3, pp. 568-577, 2010.
[20]J. Zhao, A. Wang, M. A. Green, “High-efficiency PERL and PERT silicon solar cells on FZ and MCZ substrates”, Solar Energy Materials and Solar Cells, vol. 65, no. 1-4, pp.429 - 435, 2001.
[21]H. Hannebauer, T. Dullweber, U. Baumann, T. Falcon, and R. Brendel, “21.2%-efficient fineline-printed PERC solar cell with 5 busbar front grid”, Physica Status Solidi RRL, vol. 8, no. 8, pp.675–679, 2014.
[22]P. Saint-Cast, “High-efficiency c-Si solar cells passivated with ALD and PECVD aluminum oxide”, IEEE Electron Device Letters , vol. 31, no. 7, pp.695-697, 2010.
[23]J. A. Töfflinger, A. Laades, and C. Leendertz, “PECVD-AlOx/SiNx passivation stacks on silicon: effective charge dynamics and interface defect state spectroscopy”, Energy Procedia, vol. 55, no. 1876-6102, pp. 845–854, 2014.
[24]M. Bhaisare, A. Misra, and A. Kottantharayil, “Aluminum oxide deposited by pulsed-DC reactive sputtering for crystalline silicon surface passivation”, IEEE Journal of Photovoltaics, vol. 3, no. 3, pp930~935, 2013.
[25]M. Farahmandjou and N. Golabiyan, “ New pore structure of nano-alumina (Al2O3) prepared by sol gel method”, Journal of Ceramic Processing Research, vol. 16, no. 2, pp. 1~4, 2015.
[26]T. Tsujide, S. Nakanuma, Y. Ikushima, “Properties of aluminum oxide obtain by hydrolysis of AlCl_3”, Journal of the Electrochemical Society, vol. 117, no. 5, pp.703-708, 1970.
[27]蕭丞澤，「背面利用由氯化鋁溶液形成氧化鋁鈍化層與局部接觸結構矽晶太陽能電池之研究」，國立清華大學光電工程研究所碩士班碩士論文，民國一百零九年六月。
[28]K. A. Salman, “Effect of surface texturing processes on the performance of crystalline silicon solar cell”, Solar Energy, vol. 147, pp.228-231, 2017.
[29]J. Chen, Z. H. J. Tey, Z. R. Du, F. Lin, B. Hoex, and A. G. Aberle, “Investigation of screen printed rear contacts for aluminum local back surface field silicon wafer solar cells”, IEEE Journal of Photovoltaics , vol. 3, no. 2, pp. 690-696, 2013.
[30]NTHU Y.-C. Hung Lab, “UV/VIS光譜儀 Lambda 35”, Retrieved from http://oplab.ipt.nthu.edu.tw/main/node/32
[31]Forter Tech, “Oriel Sol3A Class AAA Solar Simulators”, Retrieved from http://www.forter.com.tw/products_detail.asp?seq=2289