Effect of majority carrier space charges on minority carrier injection in dye doped polymer light-emitting devices

Excitation mechanisms in dye-doped organic light-emitting devices

In an organic light-emitting device with a polymeric matrix concurrently doped with two different dyes, the photoluminescence ~PL! and electroluminescence ~EL! spectra are observed to be very different, with both dyes emitting in PL and only one in EL at room temperature. A simple model based on charge trapping and thermal excitation is introduced to explain this observation. The EL spectral ch...

Degradation mechanism of phosphorescent-dye-doped polymer light-emitting diodes

The degradation mechanism of phosphorescent-dye-doped polymer light-emitting diodes ~PLEDs! is investigated. The active medium of our PLED is a polymer blend comprising poly~vinylcarbazole! ~PVK!, @2-~4-biphenylyl!-5-~4-tert-butyl-phenyl!-1,3,4-oxadiazole# ~t-PBD!, and platinum~II!-2,8,12,17-tetraethyl-3,7,13,18-tetramethylporphyrin ~PtOX!. The cyclic voltammetry result shows that the reductive...

Minority Carrier Lifetime in Beryllium - Doped InAs / InAsSb Strained Layer

Minority Carrier Lifetime in Beryllium-Doped InAs/InAsSb Strained Layer Superlattices Report Title Minority carrier lifetimes in undoped and Beryllium-doped Type-2 Ga-free, InAs/InAsSb strained layer superlattices (SLS) with energy gaps as low as 0.165 eV were determined from photoluminescence kinetics. The minority carrier lifetime of 450 ns at 77 K in the undoped SLS confirms a high material ...

Study of charge-carrier injection and transport in organic light-emitting diodes

Contact Injection into Polymer Light-Emitting Diodes

The variation of current I with voltage V for poly(phenylene vinylene) and other polymer light-emitting diodes has been attributed to carriers tunneling into broad conduction and valence bands. In actuality the electrons and holes tunnel into polaron levels and transport is by hopping among these levels. We show that for small injection the I-V characteristic is determined mainly by the image f...