Parts | Days | Selection | Search | Updates | Downloads | Help
DS: Fachverband Dünne Schichten
DS 39: Poster Session II
DS 39.24: Poster
Thursday, March 19, 2015, 16:00–18:30, Poster F
Investigation of Stearates as Solution-Processable Electron Injection Layers in Organic Light-Emitting Diodes — •Florian Ullrich1,2,3, Sebastian Stolz1,3, Norman Mechau1,3,4, Gerardo Hernandez-Sosa1,3,4, Malte Jesper5, Manuel Hamburger1,5, and Eric Mankel1,6 — 1InnovationLab GmbH, Heidelberg, Germany — 2University of Heidelberg, Kirchhoff-Institute for Physics, Germany — 3Karlsruhe Institute of Technology, Light Technology Institute, Germany — 4Karlsruhe Institute of Technology, Institute of Microstructure Technology, Germany — 5University of Heidelberg, Organisch-Chemisches Institut, Germany — 6TU Darmstadt, Material-Wissenschaft, Surface Science, Germany
One crucial obstacle which has to be overcome for the production of efficient organic light-emitting diodes (OLEDs) by high-throughput printing techniques is the injection of electrons into the device, since typical cathode layers with low work-functions like calcium or barium are highly reactive and cannot be solution-processed.
In this work, we investigate alkalimetal stearates as solution processable electron injection layers in OLEDs. Therefore yellow emitting OLEDs with different concentrations of Cs, Rb, K and Na stearate were fabricated and the influence on device performance, such as efficiency, efficacy and operational lifetime, was studied. For the various stearates, significantly different current efficiencies were observed with a maximum value of about 9 cd/A which equals that of reference devices. Photoelectron spectroscopy in comparison to Kelvin probe measurements as well as layer thickness characterization are in progress.