Regensburg 2002 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

SYOH: Organische Halbleiter

SYOH 7: Poster

SYOH 7.40: Poster

Montag, 11. März 2002, 18:00–21:00, C

Determination of OLED performance by simulating internal profiles of recombination, trap filling, carrier concentration and potential — •Alexander Nesterov¹, Gernot Paasch¹, and Susanne Scheinert² — ¹IFW Dresden — ²TU Ilmenau

The advantage of clarifying device properties by a full simulation of the internal electronic transport processes has been shown recently when we were able to attribute hysteresis effects in the transient OLED current to recharging of deep acceptor-like traps [1] and to describe the influence of such traps on capacitance-voltage measurements [2]. Now further results of simulation studies are presented: (i) The internal mechanism is elucidated which leads to the experimentally proven upgrade of OLED by introducing polymer modified anodes. (ii) From interface chemistry one expects the possibility that near the electrodes thin charged layers can occur which has been shown already by spectroscopy. The influence of such layers on the diode current is demonstrated. (iii) A comparison is presented between unipolar and bipolar currents in devices with different anodes, and the interplay between the filling of electron traps with different distributions with the chosen barrier heights and the direct recombination is shown. This concerns also the different influences on the internal efficiency and the position of the recombination zone.

[1] P.H. Nguyen, S. Scheinert, S. Berleb, W. Brütting, G. Paasch, Organic Electronics, 2 (2001) 105

[2] G. Paasch, S. Scheinert, Synthetic Metals, 122 (2001) 145