Imágen de Portada

Analysis of the current-voltage characteristics of polymer-based organic light-emitting diodes (OLEDs) deposited by spin coating

Polymer-based organic light-emitting diodes (OLEDs) with the structure ITO / PEDOT:PSS / MDMO-PPV / Metal were prepared by spin coating. It is known that electroluminescence of these devices is strongly dependent on the material used as cathode and on the deposition parameters of the polymer el...

Descripción completa

Autor Principal: Méndez-Pinzón, Henry Alberto; Grupo de Películas Delgadas, Departamento de Física., Facultad de Ciencias. Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed.52 Of. 606, Bogotá
Otros Autores: Pardo-Pardo, Diana Rocío; Grupo de Películas Delgadas, Departamento de Física., Facultad de Ciencias. Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed.52 Of. 606, Bogotá y Departamento de Ingeniería electrónica Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed., Cuéllar-Alvarado, Juan Pablo; Grupo de Películas Delgadas, Departamento de Física., Facultad de Ciencias. Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed.52 Of. 606, Bogotá y Departamento de Ingeniería electrónica Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed., Salcedo-Reyes, Juan Carlos; Grupo de Películas Delgadas, Departamento de Física., Facultad de Ciencias. Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed.52 Of. 606, Bogotá, Vera, Ricardo; Departamento de Química, Facultad de Ciencias. Pontificia Universidad Javeriana, Carrera 7 No. 43-82 Ed.52 Of. 606, Bogotá,, Páez-Sierra, Beynor Antonio; Qubiton laboratories K.G., Julius Raab Str. 1-3 Z.101, Linz
Formato: info:eu-repo/semantics/article
Idioma: eng
Publicado: Pontificia Universidad Javeriana 2010
Materias:
organic semiconductors, OLEDs, electroluminescent polymers, MDMO-PPV, PEDOT:PSS, Spin coating, HOMO, LUMO, carrier injection, thermionic emission
Acceso en línea: http://revistas.javeriana.edu.co/index.php/scientarium/article/view/1380
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Sumario: Polymer-based organic light-emitting diodes (OLEDs) with the structure ITO / PEDOT:PSS / MDMO-PPV / Metal were prepared by spin coating. It is known that electroluminescence of these devices is strongly dependent on the material used as cathode and on the deposition parameters of the polymer electroluminescent layer MDMO-PPV. Objective. In this work the effect of i) the frequency of the spin coater (1000-8000 rpm), ii) the concentration of the MDMO-PPV: Toluene solution, and iii) the material used as cathode (Aluminium or Silver) on the electrical response of the devices, was evaluated through current-voltage (I-V) measurements. Materials and methods. PEDOT:PPS and MDMO-PPV organic layers were deposited by spin coating on ITO substrates, and the OLED structure was completed with cathodes of aluminium and silver. The electric response of the devices was evaluated based on the I-V characteristics. Results. Diodes prepared with thinner organic films allow higher currents at lower voltages; this can be achieved either by increasing the frequency of the spin coater or by using concentrations of MDMO-PPV: Toluene lower than 2% weight. A fit of the experimental data showed that the diodes have two contributions to the current. The first one is attributed to parasitic currents between anode and cathode, and the other one is a parallel current through the organic layer, in which the carrier injection mechanism is mediated by thermionic emission. Conclusions. The results fitting and the energy level alignment through the whole structure show that PPV-based OLEDs are unipolar devices, with current mainly attributed to hole transport. Key words: organic semiconductors, OLEDs, electroluminescent polymers, MDMO-PPV, PEDOT:PSS, Spin coating, HOMO, LUMO, carrier injection, thermionic emission.

Ejemplares Similares