Polymer(Korea), Vol.19, No.6, 875-882, November, 1995
고기능 EL 소자용 고분자/유기 재료의 합성 및 전기 광학적 특성; 1. 도포법에 의한 EL 소자의 특성
Synthesis of Improved Polymer/organic Materials for Electroluminescence Device and Electro-Optical Characteristics 1. Characteristics of EL Device by Doped Polymer Method
초록
N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD)를 정공 수송제, tris(8-quinolinolato)aluminum(Ⅲ) (Alq3)를 전자 수송제 및 발광제로 사용하여 도포법에 의해 유기 ELD를 제조하였으며, 고분자 매트릭스 재료 및 이들의 제조 공정이 EL 특성에 미치는 영향에 대해 조사하였다. 고분자 매트릭스로서는 poly(methyl methacrylate) (PMMA), polycarbonate (PC) 및 Poly(vinyl carbazole) (PVK)를 사용하였다. 도포법에 의한 정공 수송층의 형성방법으로는 spin coating법과 film casting법을 비교하였으며, film casting법에 의한 정공 수송층의 형성에 있어서 용매로는 고분자에 대한 용해도가 크고 휘발성이 너무 높지 않은 dichloroethane, 그 농도는 TPD/polymer의 종류에 관계없이 0.005wt%, film casting 온도는 30℃에서 가장 안정된 EL 소자가 얻어졌다. 고분자 매트릭스의 종류에 있어서는 PMMA
Organic thin film electroluminescence devices were fabricated using by molecularly doped method with N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-bipheny1-4,4'-diamine(TPD) as a hole transport agent, tris(8-quinolinolato) aluminium(Ⅲ) (Alq3) as an omitting and electron transport agent, and poly(methyl methacrylate) (PMMA), polycarbonate (PC) and poly(viny1 carbazole) (PVK) as polymer matrices. The effect of polymer matrix and hole transport layer fabrication method of EL devices on the electroluminescence characteristics were examined. Spin coating and film casting method were compared for the formation of molecularly doped hole transport layer. The highest intensity and stability of EL device was obtained by film casting method using dichloroethane as a solvent at a polymer/TPD concentration of 0.005 wt% and film casting temperature of 30℃. The electroluminescence intensity increased in the order of PMMA3/Mg(PVK/TPD = 30/70).
Keywords:organic thin file;electroluminescence devices;molecularly doped hole transport layer;spin coating method;film casting method
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