在本研究中，我們使用商用光學模擬軟體FRED並利用光線追跡 (Ray Tracing) 技術，模擬表面織構散射結構，探討不同參數的情況下的光學特性。首先討論不同的散射體直徑對於四種入射光波長550nm、700nm、900nm及波長1200nm，從霧度及等效光程長度比來探討散射效果的優劣，進而確定適用於非晶矽太陽能電池的散射體尺寸的分佈範圍。並再就散射體的覆蓋密度作探討，發現其覆蓋密度會與等效光程長度比呈線性關係。而後模擬在不同入射光波長的主動層吸收率，換算為外部量子效率，並且分別探究單接面(Single junction)以及疊層(Tandem)電池，單接面電池主動層材料使用a-Si:H (氫化非晶矽)而疊層則是增加了μc-Si:H (氫化微晶矽)，再計算出在標準太陽光譜下的光電流及光電轉換效率。
模擬出的結果，在單接面電池的部分，最佳尺寸我們設定為0.05μm(+/-5%)，結果顯示，散射層可讓光電流值與光電轉換效率都增加約12%。另外在疊層電池方面，我們選用兩種不同的散射體尺寸做比較，分別為0.055μm(+/-5%)以及0.075μm(+/-5%)，從模擬結果得知，與無散射層的模型比較，其散射層讓短路電流密度分別增加了25.7%與22.0%，並都達到了15%的光電轉換效率。

In this work, we used commercial optical simulation software FRED to simulate surface-textured solar cells and to study the optical properties under various conditions. First we studied the scattering efficiency in terms of haze and equivalent optical path length factor as a function of scatter size for four incident light wavelengths: 550nm, 700nm, 900nm and 1200nm.Thus the ideal range in scatter size for silicon thin-film solar cells was obtained. After that, we studied and found a linear relationship between the surface coverage percentage of scatters and the equivalent optical path length factor. Then we carried out the simulations of single-junction and tandem cells respectively and obtained the absorptance of the active layers versus incident light wavelength. The materials used for the single junction and tandem cells were a-Si: H (hydrogenated amorphous silicon) and μc-Si: H (hydrogenated microcrystalline silicon), respectively. Consequently the external quantum efficiency versus incident wavelength, the short-circuit current density and the energy conversion efficiency can be obtained under standard 1-sun AM1.5G solar spectrum.
In the single-junction cell simulation, the ideal scatter size chosen was 0.05μm (+ / -5%), and the results showed that the scattering layer improved both the short-circuit current density and the conversion efficiency by about 12%. In the tandem cell simulation, compared to the one without scatters, the two tandem cells with different scatter sizes of
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0.055μm (+ / -5%) and 0.075μm (+ / -5%) helped increase the short-circuit current density by 25.7% and 22.0%, respectively, and both have reached 15% in conversion efficiency.

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