Fraunhofer ISE, the 1200-employee solar research institute in Germany, has announced a 35.9% efficiency record produced by a monolithic, triple-junction, iii-v/silicon tandem solar cell. This tandem is very closely fitted – with iii-v semiconductor later connected “directly at the atomic level to the silicon sub-cell”. This is in contrast to other tandems which are combined at the cell or even module level in the case of certain planned perovskite offerings. Group III elements include Boron, Aluminum, Gallium and Indium, while Group V consists of Nitrogen, Phosphorus, Arsenic and Antimony. A new compound semiconductor – Gallium Indium Arsenide Phosphide (GaInAsP) – has been used for the middle cell. Previously, these elements had all been seen in layers in super-high efficiency iii-v…