Analysis of deep traps in 4,4$prime;-bis(4-dimethylaminostyryl benzene) based light emitting diode devices

Autor: J. Ip, Olivier Gaudin, P. Lévêque, P. Le Rendu, Richard B. Jackman, Thien-Phap Nguyen
Rok vydání: 2004
Předmět:
Zdroj: Organic Electronics. 5:53-58
ISSN: 1566-1199
DOI: 10.1016/j.orgel.2004.02.002
Popis: Charge based deep level transient spectroscopy (Q-DLTS), a modified version of the conventional DLTS technique, has been used to characterize light emitting diodes made with 4,4′-bis(4-dimethylaminostryryl benzene) (DMASB), a poly(p-phenylene vinylene) (PPV) derivative containing amine groups. Analysis of the spectra obtained in ITO-DMASB-MgAg devices with different bias and temperature conditions has established that two types of traps exist within the band gap of the organic material. Traps of type I with a mean activation energy of ∼0.38 eV and a capture cross section of the order of 10−17 cm2 are identified as acceptor-like hole traps. These traps are believed to be distributed with a large deviation. Traps of type II have an activation energy of ∼0.50 eV and a capture cross section of the order of 10−19 cm2. They are assigned to donor-like electron traps. Comparing with the results obtained in PPV, we suggest that type I traps are related to the presence of the amine groups in the structure of the organic material.
Databáze: OpenAIRE