Interface dipoles for tuning energy level alignment in organic thin film devices.

One of the key features of organic optoelectronic and electronic devices resides in the multilayer architecture of the device stack. The performance of the latter strongly depends on the interface quality between organic layers or at the electrode heterojunction. Apart from interface thermodynamics governing adhesion and wetting, the electronic energy levels of the organic semiconductor are affected by the interface properties in a drastic way. This mini review gives a short overview on the possibilities to adjust frontier orbital energy levels using oriented electrical dipoles at the interfaces.