Interface-Investigation of Clevios-layers

The hole injection barrier (HIB) at interfaces between the electrode material and the hole injection material in OLEDs is defined by the work function of the electrode and the size of the interface dipole. Using ultra violet photoelectron spectroscopy (UPS) and Kelvin-Probe (KP) measurements all three parameters can be determined. Furthermore, the combination of both methods helps to exclude errors that might be based on the measurement technique. The performance of organic electronic devices is highly effected by the surface morphology of the employed layers. Therefore the surface morphology of all electrode materials will be investigated before and after deposition of the hole injection layer (provided by H.C. Starck) using atomic force microscopy (AFM).