Electro-optical limits of organic LED investigated through temperature and applied field dependencies

In this article, the electrical and optical properties of organic light emitting diodes (OLEDs) are analyzed, deriving the devices limits at high applied electric fields and at different temperatures. The temperature failures zones have been evaluated, studying the temperature-dependent electrical properties of the OLEDs by means of barrier parameter evaluation, and observing the charge carrier injection at metal/organic interfaces. In particular, for different device thicknesses, it is possible to detect both the surface glass transition point and the complete bulk glass transition of the amorphous organic material employed eventually correlating such mechanisms to device limitations at high applied field. (c) 2013 Society of Plastics Engineers