Organic electroluminescence (EL) single layer devices using clectroactive dyes incorporated in poly-vinylcarbazole (PVK) were fabricated. The molecular structures of the two-photon dyes are the generic D-π-A, D-π-D, and A-π-A, structural motif, composed of a diphenylamine donor (D), a distyrylfluorene π-bridge, and an oxadiazole acceptor (A). A single layer type of EL device of ITO/PVK:DYE/Ca/Al was fabricated. The light emission peak and the threshold of the electroluminescence emission depend on the structure and concentration of the dye. The EL intensity increases with the dye concentration and it was found that as the voltage is increased the brightness increases and reaches a value 498 cd/m2 at an applied voltage of 25 V for the D-π-A dye. We present a physical explanation of this observed behavior and show that this has significant impact on the design of light emitting devices using these organic dyes.
|Number of pages||6|
|Journal||Materials Research Society Symposium - Proceedings|
|State||Published - 2003|
|Event||Polymer/Metal Interfaces and Defect Mediated Phenomena in Ordered Polymers - Boston, MA, United States|
Duration: 2 Dec 2002 → 6 Dec 2002