Optimisation of rear contact geometry of high efficiency silicon solar cells using three dimensional numerical modelling

This paper describes the use of three-dimensional (3D) device modelling for the optimisation of the rear contact geometry of high-efficiency silicon solar cells. We describe the techniques and models used as well as their limitations. Our approach is contrasted with previously published 3D studies of high-efficiency silicon solar cells. Results show that the optimum spacing is about 2/3 of that predicted by 2D simulations, and exhibits a much stronger dependence on contact spacing. The optimal value found is about 60% of that of the present UNSW PERL cells, however, the possible efficiency gain is only about 0.1% absolute