ALD 아르곤 퍼지유량에 따른 Al2O3박막 분석 및 유기발광 다이오드 봉지막 적용에 관한 연구

Abstract

Organic light-emitting diode(OLED) is very thin organic films which are hundreds of nanometers. Unlike bottom-emission OLED(BEOLED), top-emission OLED(TEOLED) emits light out the front, opaque moisture absorbents or metal foils can’t be used to prevent moisture and oxygen. And it is difficult to have flexible characteristics with glass encapsulation, so thin film encapsulation which can compensate for those two disadvantages is mainly used. In this study, Al2O3 thin films by atomic layer deposition(ALD) were examined by changing the argon gas purge flow rate and we applied this Al2O3 thin films to the encapsulation of TEOLED. Ag / ITO / N,N'-Di-[(1-naphthyl)-N,N'-diphenyl]-1,1'-biphenyl-4,4'-diamine / tris-(8-hydroxyquinoline) aluminum/ LiF / Mg:Ag (1:9) were used to fabricate OLED device. The characteristics such as brightness, current density, and power efficiency are compared. And it was confirmed that with a thickness of 40 nm Al2O3 thin film encapsulation process did not affect OLED properties. And it was enough to maintain a proper OLED operation for about 9 hours.