ABSTRACT
This chapter aims to provide an overview of theoretical models and simulation approaches developed to study charge and exciton transport in organic semiconductors, as well as to predict and eventually optimize current–voltage characteristics, electroluminescence efficiency, and lifetimes of organic light-emitting diodes (OLED). It deals with the most coarse model: On a macroscopic level, the drift and diffusion of electrons, holes, and excitons in an OLED stack can be described by the corresponding densities, denoted as n, p, and s, respectively. In an OLED, charges are inhomogeneously distributed and charge density variations span several orders of magnitude. Developing an improved understanding of the mechanisms that limit the operational lifetime of OLEDs is of key importance toward the further adoption of OLED technology for display, lighting, and signage applications. The chapter reviews multiscale techniques used to simulate organic light-emitting diodes and demonstrated the feasibility of full 3D OLED modeling.
