Simulation is essential for a comprehensive analysis of the performance of solar cells. The rear contact pitch of passivated emitter and rear cells (PERC cells) is a crucial device parameter that influences not only the electrical performance but also the optical performance of these cells. This article investigates the applicability of the analytical light trapping model by Basore to account for the optical influence of the rear contact pitch as a simpler alternative to ray tracing. First, we manufacture three different groups of cells with different rear contact pitches, where the metallization fraction fmet varies between 0 and 54%. Second, the reflectance of the cells is measured. Subsequently, we fit the model parameters Rf and Rb (internal reflection on the front and back surface, respectively) to the measured reflectance. While we confirm a nonlinear relation between fmet and the measurable spectra found in previous works, our results reveal linear relations between fmet and Rb with the adjusted coefficients of determination of Radj2 > 0.97, as well as between fmet and the charge carrier generation rates with Radj2 > 0.94. These relations allow a simple and rapid optical simulation of fmet variation for PERC cells. The same approach is likely applicable to any local contacts also in other cell concepts.

中文翻译：

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PERC 太阳能电池背表面反射的参数化，包括背接触覆盖范围的变化


仿真对于全面分析太阳能电池的性能至关重要。钝化发射极和背面电池（PERC 电池）的背面接触间距是一个关键的器件参数，它不仅影响这些电池的电气性能，还影响其光学性能。本文研究了 Basore 的分析光捕获模型的适用性，以解释后接触间距的光学影响，作为光线追踪的更简单替代方案。首先，我们制造了三组具有不同背面接触间距的不同电池，其中金属化率 fmet 在 0 到 54% 之间变化。其次，测量细胞的反射率。随后，我们将模型参数 Rf 和 Rb（分别在前表面和后表面上的内反射）与测量的反射率进行拟合。虽然我们确认了 fmet 和之前工作中发现的可测量光谱之间的非线性关系，但我们的结果揭示了 fmet 和 Rb 之间与调整后的确定系数 Radj2 > 0.97 之间的线性关系，以及 fmet 和载流子生成速率之间的线性关系半径2> 0.94。这些关系允许对 PERC 电池的 fmet 变化进行简单快速的光学模拟。相同的方法可能也适用于其他单元概念中的任何本地接触。