Band bending of LiF/Alq3 interface in organic light-emitting diodes

被引：51

作者：

Ihm, K ^{[1
]}

Kang, TH

Kim, KJ

Hwang, CC

Park, YJ

Lee, KB

Kim, B

Jeon, CH

Park, CY

Kim, K

Tak, YH

机构：

[1] Pohang Accelerator Lab, Beamline Res Div, POSTECH, Pohang 790784, Kyungbuk, South Korea

[2] POSTECH, PAL, Pohang 790784, Kyungbuk, South Korea

[3] POSTECH, Dept Phys, Pohang 790784, Kyungbuk, South Korea

[4] Sungkyunkwan Univ, Dept Phys, Suwon 440746, South Korea

[5] LG Elect Inst Technol, OLED Div, Proc Grp, Gumi 730030, Kyungbuk, South Korea

来源：

APPLIED PHYSICS LETTERS | 2003年 / 83卷 / 14期

关键词：

D O I：

10.1063/1.1616977

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The insertion of LiF for an interlayer material between the Al cathode and tris-(8-hydroxyquinoline) aluminum (Alq(3)) in the organic light-emitting diodes (OLEDs) provides an improved device performance. The highly occupied molecular orbital (HOMO) level lowering in the Alq(3) layer induced by a low-coverage LiF deposition results in the reduction of electron injection barrier height. We investigated the electronic structure of the interface between the ultrathin LiF and the Alq(3) layer, using synchrotron x-ray photoelectron emission spectroscopy. The results revealed that the major origin of the HOMO level lowering is not the chemical bonding of dissociated fluorine in the Alq(3) layer but the band bending caused by charge redistribution driven by work function difference between LiF and Alq(3) layer. (C) 2003 American Institute of Physics.

引用

页码：2949 / 2951

页数：3

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