以濕式蝕刻法製備低反射率的矽奈米結構於混和型太陽能電池效率提升之研究

Study of Low-Reflectivity Silicon Nanowires Prepared with Wet Etching Method for Improving the Efficiency of Hybrid Solar Cells

林政廷(Cheng-Ting Lin)

指導教授 ： 蔡宛邵

共同指導教授 ： 陳嘉勻(Chia-Yun Chen)

國立暨南國際大學/科技學院/應用材料及光電工程學系/碩士(2017年)

摘要

本研究主要是利用簡易且低成本的濕式蝕刻法來製備大面積微奈米結構陣列，並且探討濕式蝕刻法中使用不同的化學蝕刻液所造成的表面形貌差異，最後將其製備的表面結構應用於混和型太陽能電池。
經由不同化學蝕刻液的控制，我們成功建構出四種不同的大面積表面奈米結構並將四種結構的物理性質分析完成。其中銀-金屬輔助化學一次蝕刻法製備出的垂直矽奈米線陣列其蝕刻速率和接觸角分別為110nm/min、123.40˚；銀-金屬輔助化學二次蝕刻法為頂部緊密排列之垂直矽奈米線陣列，其蝕刻速率和接觸角分別為52nm/min、126.00˚。最後，我們完成銅-金屬輔助化學蝕刻法的蝕刻特性研究，成功以氧化劑濃度控制結構的生成，因此能夠製備二種結構，分別為蛾眼結構和金字塔結構，另外我們發現蝕刻速率越大，所生成結構的尺寸也就越大，且形貌會較接近金字塔結構。
除此之外，本研究分析完成界面活性劑對於混和型太陽能電池的介面改善方式，進而提高效率，也進一步的對於高分子導電液加入各項溶劑(DMSO、乙二醇、聚乙二醇)對於電阻的改善做最佳化分析，藉此可發高分子導電液加入乙二醇後，對於電阻的改善最為明顯。而使用銀作為觸媒進行金屬輔助化學一次蝕刻法，製備出垂直的矽奈米線陣列，作為混和型太陽能電池的光電轉換效率為10.16%；銀-金屬輔助化學二次蝕刻法所製備出的垂直矽奈米線陣列，作為混和型太陽能電池的光電轉換效率為6.01%；銅-金屬輔助化學蝕刻法製備出的蛾眼結構及金字塔結構，分別作為混和型太陽能電池的光電轉換效率10.78%和8.80%。

關鍵字

濕式蝕刻法 ； 低反射率 ； 矽奈米結構 ； 混和型太陽能電池

並列摘要

In this study, the large areas of micro- and nano-structure arrays were fabricated using a simple and low-cost metal-assisted chemical etching method. The differences in surface morphologies caused by various etching methods were investigated. Finally, the prepared nanostructures were applied for the construction of hybrid solar cells. In addition, four kinds of surface nanostructures were analyzed and tested. Explorations of using different surfactants for improving the efficiency of hybrid solar cells were performed, Furthermore, various solvents (DMSO, ethylene glycol, polyethylene glycol) were added to the polymer precursors to study the optimum addition of solvents for reducing the sheet resistance of polymer films. It was found that the use of ethylene glycol to reduce the polymer resistance and further leads to the improved conversion efficiency of hybrid solar cells.
In this study, one-step Ag-metal assisted chemical etching method was used to prepare the vertically aligned silicon nanowire arrays. The average etch rate was found to be 110 nm/min. Photoelectric conversion efficiency of 10.16% as a hybrid solar cell was realized with the incorporation of silicon nanowire arrays. In addition, two-steps Ag-metal assisted chemical method also resulted in the formation of straight silicon nanowire arrays with the closely packed top surfaces. The average etch rate was 52 nm/min. In this case, photoelectric conversion efficiency was 6.01%. Finally, Cu-metal assisted chemical etching method was used to prepare moth-eye and pyramid-like nanostructures depending on the oxidant concentrations. The corresponding solar cells demonstrated the photoelectric conversion efficiency of 10.78% and 8.80%, respectively.

並列關鍵字

Wet etching method ； Low reflectivity ； Silicon nanowires ； Hybrid solar cells

參考文獻

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