Role of the deep-lying electronic states of MoO3 in the enhancement of hole-injection in organic thin films

被引:609
作者
Kroeger, M. [1 ]
Hamwi, S. [2 ]
Meyer, J. [2 ]
Riedl, T. [2 ]
Kowalsky, W. [2 ]
Kahn, A. [1 ]
机构
[1] Princeton Univ, Dept Elect Engn, Princeton, NJ 08544 USA
[2] Tech Univ Carolo Wilhelmina Braunschweig, Inst Hochfrequenztech, D-38092 Braunschweig, Germany
基金
美国国家科学基金会;
关键词
LIGHT-EMITTING-DIODES; METAL-OXIDES; MOLYBDENUM OXIDE; INTERFACES; LAYER; XPS; AL; AG;
D O I
10.1063/1.3231928
中图分类号
O59 [应用物理学];
学科分类号
摘要
The electronic structures of vacuum-deposited molybdenum trioxide (MoO3) and of a typical MoO3/hole transport material (HTM) interface are determined via ultraviolet and inverse photoelectron spectroscopy. Electron affinity and ionization energy of MoO3 are found to be 6.7 and 9.68 eV, more than 4 eV larger than generally assumed, leading to a revised interpretation of the role of MoO3 in hole injection in organic devices. The MoO3 films are strongly n-type. The electronic structure of the oxide/HTM interface shows that hole injection proceeds via electron extraction from the HTM highest occupied molecular orbital through the low-lying conduction band of MoO3. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3231928]
引用
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页数:3
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