Preparation of Single‐Crystalline Heterojunctions for Organic Electronics

Organic single‐crystalline heterojunctions are composed of different single crystals interfaced together. The intrinsic highly ordered heterostructure in these multicomponent solids holds the capacity for multifunctions, as well as superior charge‐transporting properties, promising high‐performance electronic applications such as ambipolar transistors and solar cells. However, this kind of heterojunction is not easily available and the preparation methods need to be developed. Recent advances in the efficient strategies that have emerged in yielding high‐quality single‐crystalline heterojunctions are highlighted here. The advantages and limitations of each strategy are also discussed. The obtained single‐crystalline heterojunctions have started to exhibit rich physical properties, including metallic conduction, photovoltaic effects, and so on. Further structural optimization of the heterojunctions to accommodate the electronic device configuration is necessary to significantly advance this research direction. The recent progress of organic single‐crystalline heterojunctions with single crystals interfaced together is highlighted, with a focus on the advances in the efficient strategies for fabricating high‐quality heterostructures and exploring the resulting devices from the viewpoint of both their fundamental physics and electronic applications.