Numerical Analysis on Electro-Optic Properties of PEDOT/HTL/mCP/ETL/Alq3 Multilayer OLED Device Structure

초록

In this paper, we report our numerical study on the electrical-optical properties of the organic light emitting diodes (OLEDs). We employed the finite element (FEM) approach in order to analyze the electrical-optical profiles, which contain the transport behavior of electrons and holes, the generation and decay of exciton, and emission properties. Our model includes Poisson’s equation, continuity equation to account for behavior of electrons and holes and the exciton continuity/transfer equation to account for recombination of carriers. We employ the multilayer structure that consists of poly(3,4-ethylenedioxythiophene)–polystyrenesulfonic acid (PEDOT:PSS); 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC); 4,4 ′ -bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (α-NPD); 4,4´-bis[N-(p-tolyl)-N-phenylamino] biphenyl (TPD); fac-tris(2-phenylpyridinato)iridium(III) (Ir(ppy)3); 3,5´-N,N´-dicarbazole-benzene (mCP); 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP); 4,7-diphenyl-1,10-phenanthroline (BPhen); tris(8-quinolinolato) aluminum (Alq3). We observed the effect of different hole transport layer following TAPC, α-NPD, TPD. And we also observe the effect of different electron transport layer following BCP, Bphen. We found that the charge balance has a strong effect such as the device efficiency, the generation of exciton.