近幾年來，各種粗糙化結構對矽基太陽能電池所產生的影響引起廣泛的研究。在本論文中，我們利用二維模擬軟體 Sentaurus TCAD 及 Lumerical FDTD，探討平面非晶矽薄膜太陽能電池吸收層厚度對於電性特性的影響，利用 Lumerical FDTD 視各種不同的微結構條件對於非晶矽薄膜太陽能電池在光性特性上的影響。利用 Sentaurus TCAD 模擬平面電池(Glass/ TCO/ a-Si:H(p)/ a-Si:H(i)/ a-Si:H(n)/TCO/ EVA)不同的本質層厚度 a-Si:H(i)，得知薄的本質層厚度(100 nm)可使電池的短路電流值達 5.55mA/cm2，外部效率達 14%。由電性表現的關係結果，發現本質層厚度越厚，可使較多的光生電子電洞對被收集(I=500nm, Jsc=8.78mA/cm2)，然而事實上其高比例的缺陷態密度也會隨之增加，且光衰退的影響會更趨明顯與嚴重。為使較薄的本質層(I=100nm)模型達到更好的效率，本論文利用 Lumerical FDTD 軟體以建立微結構的方式彌補其與較厚本質層模型在短路電流上的差異。就單層玻璃介面微結構而言，隨著結構高度(H)的增加，特徵峰值大小會逐漸減低，故就抗反射效果而言，選用較小的微結構高度如 0.2μm 或 0.4μm，次波長等級的周期(380nm<P<760nm)則會有較佳表現。就多層均質性沉積的薄膜矽太陽能電池而言，我們調變三角微結構週期/高度為範圍 0.2-1μm/0.1-1μm，期望能在「極佳抗反射」以及「低的背電極散射損耗」間取得平衡，並獲得最佳短路電流值。本質層厚度為 300nm 的電池模型(P=0.8μm、H=0.8μm)，其短路電流為 18.67mA/cm2。對平面電池的增益為 49%；若本質層厚度為 100nm (P=0.2μm、H=0.5μm)，短路電流與增益分別為18.39mA/cm2 及 73%。從外部量子效率圖中亦可發現，本徵層較薄的模型，其增益效果較為明顯。Recently, the effect of few kinds of texturing structures on solar cell has been received intense attention and plenty of researches. In this thesis, we use SentaurusTCAD and Lumerical FDTD to study the effect of intrinsic layer thickness and different microstructure on amorphous silicon thin film solar cell. First of all, we establish the plane type a-Si solar cells (Glass/ TCO/ a-Si:H(p)/ a-Si:H(i)/ a-Si:H(n)/ TCO/ EVA) in the two programs. By the utilization in Sentaurus TCAD, we find the short circuitcurrent in the thinner intrinsic layer (100nm) model achieves 5.55mA/cm2, while the external quantum efficiency achieves 14%. Additionally, if the high-defected intrinsiclayer gets thicker, there are more photogenerated carriers but higher defect density of state but more serious light degradation. Replacing that by thinner intrinsic layer andmodulating the microstructure of the solar cell in Lumerical FDTD are the ways to compensate for the lack of short circuit current brought from the thinner thickness. Reflection peak of textured glass (microstructure and glass film) gets reduced by the increasing structure height. For being the superior anti-reflection, sub-wavelength microstructure would be a good choice as choosing small structure height. For the muti-layer textured solar cell, how to get balanced between superior AR and low scatter dispersion at the back contact is a crucial topic. The solar cell with 300nm intrinsic layer has its short circuit current achieving 18.67mA/cm2 and enhancement 49% with P=0.8μm and H=0.8μm. Whereas the solar cell with 100nmintrinsic layer has its short circuit current 18.39mA/cm2 and enhancement 73% with P=0.2μm and H=0.5μm. From the result of external quantum efficiency, it is found that the thinner intrinsic layer performs the more obvious enhancement effect.
