隨著太陽電池走向大面積化，如何提升基板導電性是當前產學界努力的目標。目前最常使用的方式是利用金屬格線來降低基板阻值，藉由高密度的金屬格線降低整體電阻，以提升整體大面積太陽電池的元件效率。然而，金屬格線所造成的遮光效應，同時會使元件的照光區域減少而降低效率。因此，如何找出最適金屬格線圖樣以最佳化元件表現成為一項重要的議題。本篇論文即對金屬格線的圖樣做討論，提出一種新的圖樣，並建立一套可找出各種太陽電池之最佳金屬格線圖樣的模擬系統。
本研究將以真實的小面積太陽電池數據為基礎，依據電路模型建立二維大面積太陽電池的結構，模擬搭配金屬格線之大面積太陽電池與串接式太陽電池情形，此外，亦探討金屬格線對不同材料與不同填充因子之大面積太陽電池影響，最後考慮金屬格線遮光因素，並對這些結果做分析與討論。本套模擬系統可針對各種太陽電池情況做模擬，找出最適合之金屬格線圖樣，可望在現今太陽電池產業中有很高的應用價值。

The modeling of two-dimensional large-area solar cells
Student：Yu-Ting Hsu Advisor：Prof. Sheng-Fu Horng
Institute of Electronics Engineering
National Tsing Hua University

Abstract
In this study, various grid patterns were investigated by a simulation method for optimization of efficiency. Since low conductivity of the large-area solar cells will result in poor device performance, introducing metal grid to reduce the resistance of the substrate has been widely used. However, it is very important to find out a proper grid pattern to optimize the conductivity and shading effect. In our research, we have investigated a new kind of metal grid pattern, and we also constructed a system to find the best metal grid pattern in various devices, which can be a reference in the PV industry.
First, we build the simulation model of the large-area solar cell with metal grid by real small-area solar cell using the circuit model and the mathematical method. Then we discuss the effect of the grid pattern to the solar cells, and analyze the result from several factors which affecting the efficiency of the device, including the short-circuit current and fill factor of the small area solar cell in the ideal condition. Finally, the shadow effect is considered to approach a real case.

Keyword：large-area, solar cells, metal grid

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