A Study on the Fabrication and Characteristic Analysis of Blue Organic Light Emitting Devices

청색 유기발광소자 제작 및 특성분석에 관한 연구

  • Published : 2002.03.01

Abstract

In this thesis, blue emission organic light emitting devices were fabricated by using vacuum deposition method. Two types of device were employed to realize blue emission. Type I had an emitting layer containing TPB-doped $Alq_3$ and type II had an emitting layer containing DPA-doped $Alq_3$. The variable dopant concentration was 0.5 ~2 wt%. The electrical and optical characteristics of these devices have been investigated. The more dopant concentration increased, the nearer the blue coordinate. Type I than type II had a lower turn on voltage and driving voltage. The emission luminescence of type II was brighter than that of type I. When we applied 15V to type II with DPA(2wt%)-doped $Alq_3$, we have achived the emission luminescence of 1282cd/$m^2$, the emission wavelength of 476nm and the blue emission CIE coordination of (0.1273, 0.0672)

본 논문은 청색 유기 EL 소자를 진공증착법으로 제작하여 그 특성을 분석하였다. 발광층 물질(A1q/sub 3/)에 게스트물질(Type I-TPB와 Type II-DPA)의 도핑농도(0.5∼2 wt%)를 변화시켜 청색발광소자를 제작하여 전기적, 광학적 특성을 조사하였다. Alq3에 도펀트의 농도를 증가함에 따라 청색에 해당하는 색좌표 점으로 이동하였다. Type I이 Type II의 경우보다 동작개시전압 및 구동전압이 낮게 나타났으며 휘도에서는 Type II가 밝게 나타났다. Alq/sub 3/에 DPA(2wt%)를 도펀트로 사용한 소자의 경우 인가전압 15V에서 휘도는 1282cd/m/sup 2/, 최대발광 파장은 476nm, 색좌표는(0.1273, 0.0672)으로 우수한 특성을 나타내었다.

Keywords

References

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