Simulation and modeling of C-V curves of OLEDs with trap states for the holes

Simulations of dynamic capacitance-voltage (C-V) curves for organic light e mitting diodes (OLED) with deep traps for the holes are presented. A system atic variation of parameters leads to clearly identifiable variations of th e C-V curves. An equivalent circuit is deduced from the ac small-signal equ ations. In connection with the Nyquist representation of the dielectric fun ction it is well suited to extract trap- and other material parameters from experiments. (C) 2001 Elsevier Science B.V. All rights reserved.