Photovoltaics
High-efficiency solar cells for concentrators and satellites
High-efficiency stacked solar cells are stacks of solar cells made of different semiconductors. The semiconductors are carefully chosen to absorb nearly the entire solar spectrum. The resulting stacks are capable of efficiencies up to 35%, and will be used in satellites and earth-based concentrators.
Imec's R&D focus is on stacked cells with III-V top cells and Ge bottom cells. Current research involves, among others, epitaxially growing single junction GaAs and dual junction InGaP/GaAs solar cells on germanium substrates using an improved manufacturing technology. Next to further developing the individual top and bottom cells, Imec is optimizing the process of stacking the top and bottom cells, and of handling the thinned-down top cells.