유기 발광 소자에서 정공 주입 버퍼층에 의한 전압-전류-휘도 특성

Voltage-Current-luminance Characteristics of Organic : Light-Emitting Diodes depending on Hole-Injection Buffer Layer

In this work, we have seen the effect of hole-transporting layer in organic light-emitting diodes using N,N'-biphenyl-N,N'-bis-(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine(TPD) and N,N'-biphenyl-N,N'-bis-(1-naphenyl)-[1,1'-biphenyl]-4,4'-diamine(NPB). NPB is regarded as a better hole trans porting material than TPD, since it has a higher glass transition temperature$(T_g)$. And current -voltage, luminance-voltage and external quantum efficiency of device were measured with the thickness variation of buffer layer using copper phathalocyanine(CuPc) and polytetrafluoroethylene (PTFE) at room temperature. We have obtained an improvement of External quantum efficiency when the CuPc 30[nm] and PTFE 1.0[nm] is used.