Den Energieniveaus auf der Spur

Tracking energy levels – Photoelectron spectroscopy helps in finding novel semiconductor materials Research on novel semiconducting materials keeps attracting considerable interest due to the potential to develop more cost effective processing compared to conventional inorganic technology. Maybe more importantly, novel device concept become possible such as flexible or semitransparent displays and solar cells. Two of the most promising candidates are introduced here: organic semiconductors as well as halide perovskites. In both material classes, it is possible to tune the absorption or emission properties over a wide range by adjusting the structure or composition or the material. In order to effectively integrate these materials in devices, it is necessary to understand their fundamental properties. Here, the vacuum based photoelectron spectroscopy plays an important role, due to the possibility to directly map the electronic structure of the semiconducting or adjacent layers, which in turn determines the charge transport throughout the device.