'Odd couple' monolayer semiconductors align to advance optoelectronics

Epitaxy, or growing crystalline film layers that are templated by a crystalline substrate, is a mainstay of manufacturing transistors and semiconductors. If the material in one deposited layer is the same as the material in the next layer, it can be energetically favorable for strong bonds to form between the highly ordered, perfectly matched layers. In contrast, trying to layer dissimilar materials is a great challenge if the crystal lattices don't match up easily. Then, weak van der Waals forc