Advanced approaches in optical simulations of thin-film solar cells

Abstract

In rigorous optical modeling and simulation of thin-film solar cells a few constraints and bottlenecks have been addressed recently. Two of them are related to how to include thick incoherent layers in the coherent finite element based simulations and how to describe and include non-conformal growth of layers in a thin-film solar cell. In this paper we present and apply three different solutions to speed up and improve the simulations of realistic thin-film solar cell in superstrate configuration: (i) solutions for including optically thick incoherent glass layer in superstrate type of solar cells and (ii) how to consider its thickness in millimeter range and and (iii) we present a non-conformal layer growth model. By applying these advanced features to 3-D optical modeling, it becomes possible to simulate the complete solar cell structures (incl. front glass) rigorously and time efficiently and to consider the realistic textures at all internal interfaces thus gaining in accuracy of simulations.