Optical Simulation of Light Management in CIGS Thin-Film Solar Cells Using Finite Element Method

In this paper we present an optical simulation of light management in Cu(In,Ga)Se-2 thin-film solar cells with reduced absorber layer thickness, with the goal of absorption enhancement in the absorber layer. The light management was achieved by texturing of the substrate layer, and the conformal growth of all the following layers was assumed. Two texturing shapes have been explored: triangular and convex, with different periods and height aspect ratios. The simulations have shown that significant enhancement of absorption within the absorber layer can be achieved using the proposed geometry. The results showed that the triangular textures with small periods (100-200 nm) and high aspect ratios have the most prominent effect on the enhancement of absorption within the absorber layer, although they are difficult to achieve experimentally.