Growth of a Cu(In, Ga)Se${}_2$ (CIGS) layer during a selenization process is numerically studied to understand mechanisms for formation of stains on large-area substrates batched. CIGS layers need to be uniformly deposited onto the substrates to obtain even conversion efficiency. However, it is difficult to control growth of large-area CIGS layers due to turbulent thermal-fluid flow leaving stains on the substrates. In the present research, the selenization process for an industrial-scale substrates of which sizes are order of square-meters is considered with integrated simulations of detailed key physical processes such turbulent convection, convective-radiative-conductive heat transfer, and chemical reactions. Ascending or descending gas generated by heaters is identified by the time-averaged velocity fields. Descending flow in the passages between substrates produces uneven flow rates across the substrates leading to inhomogeneous supply of heat energy and gas species to the surface chemical reactions. The uneven temperature distribution is the major cause for the stain formation on the substrates. Gross shapes of the stains are found to be well matched with the predicted velocity contour of gas flow above the substrate. The stains are expected to be alleviated by rectifying gas flow such that flow rates become uniform across substrates before entering the passages.

Cu(In, Ga)Se 的生长${}_2$对硒化过程中的 (CIGS) 层进行了数值研究，以了解在批量处理的大面积基板上形成污渍的机制。CIGS 层需要均匀地沉积在基板上以获得均匀的转换效率。然而，由于湍流热流体流动会在基板上留下污渍，因此难以控制大面积 CIGS 层的生长。在本研究中，通过对湍流对流、对流-辐射-传导传热和化学反应等详细关键物理过程的综合模拟，考虑了尺寸为平方米数量级的工业规模基板的硒化过程。由加热器产生的上升或下降气体由时间平均速度场识别。基板之间的通道中的下降流会在基板上产生不均匀的流速，从而导致向表面化学反应提供的热能和气体种类不均匀。不均匀的温度分布是在基材上形成污点的主要原因。发现污点的总体形状与基板上方气流的预测速度轮廓很好地匹配。通过整流气流使得流率在进入通道之前在基板上变得均匀，预计可以减轻污点。发现污点的总体形状与基板上方气流的预测速度轮廓很好地匹配。通过整流气流使得流率在进入通道之前在基板上变得均匀，预计可以减轻污点。发现污点的总体形状与基板上方气流的预测速度轮廓很好地匹配。通过整流气流使得流率在进入通道之前在基板上变得均匀，预计可以减轻污点。