Regensburg 2019 – wissenschaftliches Programm
CPP 14.4: Vortrag
Montag, 1. April 2019, 15:45–16:00, H31
Influence of thermal transport parameters on operation temperature of OLEDs — •Georgii Krikun and Karin Zojer — Institute of Solid State Physics, NAWI Graz, Graz University of Technology, Graz, Austria
Utilizing organic light emitting diodes (OLEDs) for lighting requires a homogeneous operation across large surface areas. This poses the challenge to suppress local variations in temperature and current density. While OLED research mostly focuses on electric and optical properties, thermal properties are highly relevant, as charge transport in organics is thermally activated. Due to the peculiar coupling between thermal and charge transport, related properties cannot be decoupled from each other.
We investigate how thermal conductivity and heat transfer between OLED surface and environment impact current voltage relations and device temperature for a given ambient temperature. By using self-consistent drift-diffusion based simulations, that simultaneously account for thermal and charge transport and their coupling, we establish how excess heating can be effectively counteracted. Despite a strong coupling between charge and heat transport, heat transport is essentially governed by layers that not participate in charge transport. Hence, electrical and thermal properties can be tuned with separate layers.