Approaches and challenges in optical modelling and simulation of thin-film solar cells

Optical modelling and simulations present an indispensable tool in the design, analysis and optimisation of thin-film solar cells of different technologies. In this paper highlights and challenges of different numerical modelling approaches are reviewed, from one-dimensional to rigorous two- or three-dimensional optical modelling. A concept of Coupled Modelling Approach (CMA) is proposed to be used, in which different optical models are coupled together to achieve best performance in speed and accuracy of simulations. A Combined Ray-Optics Wave-optics Model (CROWM) is presented as a simple example of the CMA. In the second part two examples of modelling and simulations are presented. To demonstrate the applicability of 3-D rigorous optical modelling, results of optimisation of periodic substrate surface texture in a micromorph silicon solar cell are shown. Furthermore, a model of non-conformal layer growth is employed to determine morphologies of internal interfaces and to make a selection of suitable textures for defect-less thin-film silicon layer growth. The CROWM simulator was employed to demonstrate the usability of coupled modelling on the example of optimisation of macro-textures in organic solar cells. (C) 2014 Elsevier B.V. All rights reserved.