非晶矽多接面太陽能電池模擬

Abstract

在能源耗竭的現今，替代能源的發展已經是未來的趨勢，而在眾多替代能源中，其中又以太陽能發電為最乾淨、環保、且取之不盡用之不竭的再生能源。所以在發展各種不同種類的太陽能電池，我們選擇了非晶矽薄膜太陽能電池來做為研究的主題。 薄膜太陽電池可以使用在價格低廉的玻璃、塑膠、陶瓷、石墨，金屬片等不同材料當基板來製造，形成可產生電壓的薄膜厚度僅需數μm，因此在同一受光面積之下可較矽晶圓太陽能電池大幅減少原料的用量，且薄膜電池太陽電池除了平面之外，也因為具有可撓性可以製作成非平面構造，所以其應用範圍大，可與建築物結合或是變成建築體的一部份。非晶矽薄膜太陽能電池在其效率上並不算高，甚至比傳統的結晶矽太陽能電池還要來的低，但是由於在製程上完熟的技術、具有可撓性、可以接合在建築材料上等種種優點，使的非晶矽太陽能電池的研究還是非常熱門。 而這項研究主要著重於非晶矽材料用做薄膜太陽能電池的時候，有兩項不同於其他太陽能電池的特點，一項是非晶矽材料的尾帶結構，另一項則是太陽能電池表面粗化的特色。而我們藉由了解尾帶結構的物理模型，模擬並分析非晶矽材料由於尾帶結構造成的二次吸收，進而調整尾帶的參數來觀察各參數對於太陽能電池的影響。而另一項對於表面粗化結構的模擬，我們建立兩種不同的表面粗化結構。第一種是使用霧度公式添加到平坦的太陽能電池表面上，電池表面入射的光會產生散射，從而達到表面粗化的效果。第二種方式則是參考真實的表面粗化結構，並將此結構以座標的形式建立起一個類真實結構的平面，再藉由模擬了解其粗糙面太陽能電池的特性。 而最後則是將表面粗化結構和尾帶結構兩者相結合並模擬，和實驗量測到的數據來做擬合，增加模擬的準確性。建立一個模擬非晶矽薄膜太陽能電池，並且具備一定準確性的平台是我們這項研究的目標。

Due to the depletion of energy resources, alternative energy development is the trend of the future. There are many alternative energy sources, and the solar power is a clean, environmentally friendly, renewable and inexhaustible one among them. Among several types of solar cells that are currently with high attention, we chose the amorphous silicon thin-film solar cells for the subject. Thin-film solar cells can be produced on the substrates which could use inexpensive glass, plastics, ceramics, graphite, or metal, and the film only needs a few μm to produce photo-generated voltages. So under the same light-receiving area, thin-film solar cell can significantly use less amount of raw materials than the conventional silicon solar cell. One of the important characteristics of thin film solar cells is flexibility. Its flexible properties can be applied to a wide variety of surfaces even combined with the building and window. Amorphous silicon thin-film solar cell does not surpass its crystalline counterpart for high efficiency. But due to severaladvantages such as mature manufacturing process, flexibility, and combined with the building materials, the amorphous silicon solar cell research is still very popular. This research is focused on features which are different from other solar cells. One is the band tail structure of amorphous silicon materials, and the other is surface roughness. By studying the band tail physical model, we can devise the band tail absorption by tuning its parameters. And another topic is the surface roughness. We create two different surface roughness of the structure. First we use haze formula to simulate the flat structure with haze by ideal situation. On the other hand, we established the real textured surface for simulating in order to achieve the real situation. Finally, we combine the surface roughness and band tail in our simulation structure, and fitting the simulation results to the experimental data to enhance the simulation accuracy. Combination of these two features on a commercially available software is very important to expand our research for greater use. The accuracy of the simulation verified by the fitting process can ensure the validity of our band tail model and texture interface. We hope this application can be useful for design of the next generation thin film solar cell.