TACIT

The project TACIt main concern ist to identify the most effective light trapping (LT) strategies to improve the efficiency of a 3-terminal tandem solar cell, based on a crystalline Si (c-Si) silicon cell. Besides the c-si solar cell, the tandem solar cell includes a SiGe sub-cell and a high band gap (Eg>1.7 eV) solar cell. The ideal material and geometry of the top-cell will be determined by computer simulations. Computer simulations will also help to identify the best LT strategies to be used in each tandem cell region. The tandem cell architecture used doesn’t require current matching, hence the sub-cells currents can be independently optimized. Two different types of LT strategies will be used: one based on metal-assisted chemical etching (Mace), and the other based on nanofabrication of LT structures and deposition of high index dielectric materials. Advanced passivation schemes will be applied to the Mace LT structures to reduce surface recombination.