請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/77884
標題: | 高效率有機混合矽太陽能電池之研究 The Examination of High Efficiency Organic Hybrid Silicon Solar Cells |
作者: | Yi Lai 賴毅 |
指導教授: | 林清富(Ching-Fuh Lin) |
關鍵字: | 有機混合矽太陽能電池,矽奈米洞結構,有機材料,旋塗製程,異質接面,稀釋法,指狀電極,銀奈米線, Organic hybrid silicon solar cells,Silicon nanoholes,PEDOT:PSS,Solution process,Heterojunction,Dilution method,Finger electrode,Silver nanowires, |
出版年 : | 2017 |
學位: | 碩士 |
摘要: | 十八世紀開始,由於蒸氣機的發明,人類開始使用石化燃料,隨著科技的進步以及能源需求的增大。現今太陽能電池中,以矽基太陽能電池為主,但目前矽基太陽能電池與石化燃料等發電相比之下,成本價格仍偏高。因此,考慮目前矽基太陽能電池中PN-junction的生成、表面鈍化以及抗反射層,通常皆需高溫高真空製程以及高成本且耗時之儀器。往後太陽能電池將大量生產與商業化的考量下,必須改善以下重點:元件效率、製作成本與時間,以及廣泛多元運用。
在本篇碩士論文中,首先,我使用比一般抗反射層較低成本的金屬輔助化學蝕刻(metal assisted chemical etching)來製作低反射且高吸光性的矽奈米洞結構(Silicon nanaholes, SiNHs)於矽基板上。再將矽奈米洞結構(SiNHs)與有機材料PEDOT:PSS接合,形成有機混成矽太陽能電池。由於我們使用PEDOT:PSS取代傳統矽基太陽能電池之P層,僅需使用旋轉塗佈機(Spin coater)以及烤盤(Hot plate)即可完成PEDOT:PSS薄膜,在此簡單且低成本之製程下,元件轉換效率可達10.09%。 為了使得元件的效率提升,在本碩士論文中,對於有機材料PEDOT:PSS之吸光部分進行研究。由合作實驗室提供之模擬結果得知,PEDOT:PSS於600nm之後的吸收係數將會大於矽基板,若旋塗的成膜厚度過厚,會進而影響到元件的光電流。在此我使用稀釋法來改善PEDOT:PSS厚度問題,稀釋完PEDOT:PSS後,可以有效降低PEDOT::PSS吸光,對於整體元件的光電流也是有所提升。但在使用此種稀釋法將會遇到另一個衍生的問題:PEDOT:PSS與透明導電薄膜ITO的接觸會變差,元件會無法穩定的接合在ITO,最終導致良率非常差。因此,我提出取代透明導電薄膜的一種辦法:使用金屬指狀電極來取代透明導電薄膜ITO。此方法可以直接且有效解決稀釋PEDOT:PSS後與ITO接觸變差的問題,但製作元件後發現指狀電極與PEDOT:PSS之接觸電阻會上升,且開路電壓也下降,導致整體元件效率下降。 為了解決稀釋造成的表面缺陷以及PEDOT:PSS與指狀電極的接觸問題,於最後一章提出旋塗銀奈米線於指狀電極與PEDOT:PSS之間,藉以形成全面性電極增進元件之電性。在銀奈米線的尺寸選擇上,先從尺寸小的銀奈米線進行嘗試,但是小尺寸之銀奈米線很容易有群聚現象產生,因此只能使用較大尺寸的銀奈米線進行旋塗,於元件應用上也有顯著地幫助,成功使得元件改善表面缺陷問題。此外,為了降低旋塗銀奈米線所造成的高反射問題,於銀奈米線中使用IPA來稀釋並降低銀奈米線的濃度,成功製作出具有高光電流且不影響元件電性的有機混合矽太陽能電池,其光電轉換效率達到14.18%,並於最後搭配背面擴散N+層來增加內建電場提升開路電壓,可以成功製作出14.56%的太陽能電池。 After the invention of the steam engine since eighteenth century, human beings began to use fossil fuels. As technology advances, energy demand increases year after year, so solar energy has increasing importance. Among all solar cells, the silicon-based solar cells are the mostly used. However, the price of solar cells is higher than the fossil fuels. Also, the silicon-based solar cells are still associated with expensive and time consuming of high temperature and high vacuum process due to the needs of PN-junction formation, surface passivation and anti-reflective coating, and so on. In the future, reducing the cost of Si-based solar cells is the most important, so we must focus on these points: device efficiency, production cost and time, extensive and diversified use. In this thesis, metal-assisted chemical etching is used to produce low reflection and high absorption of silicon nanostructures (Silicon nanaholes, SiNHs) on silicon substrates. Then organic material PEDOT:PSS is coated on SiNHs to fabricate organic hybrid silicon solar cells. Since we use PEDOT:PSS instead of the P layer in traditional silicon-based solar cell, it only needs the spin coater and hot plate to form the PEDOT:PSS film. In this simple and low-cost process, the efficiency can approach 10.09%. In order to further improve the efficiency of the solar cells, this thesis then focuses on the organic material PEDOT:PSS light absorption part of the study. According to the simulation results provided by the cooperative laboratory, it is shown that the absorption coefficient of PEDOT:PSS could be larger than silicon after 600nm. If the film thickness is too thick, it may affect the photocurrent in solar cells. Thus diluting method is used to reduce the PEDOT:PSS thickness. After dilution, the PEDOT:PSS absorption could be effectively reduced. The device photocurrent is also improved. However, diluting method will cause another derivative problem. PEDOT:PSS contact with the transparent conductive film ITO becomes very bad and the yield is very poor. In order to solve the problem of contact caused by dilution, I proposed adding silver nanowires (AgNWs) between the finger electrode and PEDOT:PSS. In the size selection of the AgNWs. I chose the small size of the AgNWs, but the small size of the AgNWs always create the phenomenon of clustering. Thus, I use a larger size of AgNWs. It successfully improves the surface defects, and enhances solar cell efficiency to 12.43%. Finally, in order to reduce the high reflection problem caused by the AgNWs, the diluting method is used to reduce the concentration in the silver nanowires. Through adjusting the parameters, the high photocurrent is achieved without affecting the organic hybrid silicon solar cells. The photoelectric conversion efficiency can reach 14.18%. In addition, I use backside diffusion to add an N+ layer in the back of Si wafer to increase open-circuit voltage. The power conversion efficiency is finally improved to 14.56%. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/77884 |
DOI: | 10.6342/NTU201703350 |
全文授權: | 有償授權 |
顯示於系所單位: | 光電工程學研究所 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-106-R04941108-1.pdf 目前未授權公開取用 | 4.16 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。