Electronegativity and charge-injection barrier at organic/metal interfaces

被引:33
作者
Tang, JX
Lee, CS
Lee, ST
Xu, YB
机构
[1] City Univ Hong Kong, COSDAF, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China
[2] Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China
关键词
D O I
10.1016/j.cplett.2004.08.021
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Despite a large scatter in experimental data, charge-injection barrier at organic/metal interfaces has been traditionally described as a function of metal work function. By studying the interface between Alq(3) and various metals with photoelectron spectroscopy, we show that the charge-injection barrier can be better described as a linear function of the metal electronegativity. This is consistent with our theoretical analysis in terms of a simple model involving metal-induced gap states in organic layer. The interface parameter S is calculated to be 0.8, in good accordance with the experimental value of 0.81. The present work presents a method for predicting the injection barrier at organic/metal interfaces and should be useful for designing various organic-based electronic and optoelectronic devices. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:92 / 96
页数:5
相关论文
共 22 条
[1]   SCHOTTKY AND BARDEEN LIMITS FOR SCHOTTKY BARRIERS [J].
COHEN, ML .
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY, 1979, 16 (05) :1135-1136
[2]   Characterization of the interface dipole at organic/metal interfaces [J].
Crispin, X ;
Geskin, V ;
Crispin, A ;
Cornil, J ;
Lazzaroni, R ;
Salaneck, WR ;
Brédas, JL .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2002, 124 (27) :8131-8141
[3]   Molecular level alignment at organic semiconductor-metal interfaces [J].
Hill, IG ;
Rajagopal, A ;
Kahn, A ;
Hu, Y .
APPLIED PHYSICS LETTERS, 1998, 73 (05) :662-664
[4]   Charge-separation energy in films of π-conjugated organic molecules [J].
Hill, IG ;
Kahn, A ;
Soos, ZG ;
Pascal, RA .
CHEMICAL PHYSICS LETTERS, 2000, 327 (3-4) :181-188
[5]   Recent progress of molecular organic electroluminescent materials and devices [J].
Hung, LS ;
Chen, CH .
MATERIALS SCIENCE & ENGINEERING R-REPORTS, 2002, 39 (5-6) :143-222
[6]  
Ishii H, 1999, ADV MATER, V11, P605, DOI 10.1002/(SICI)1521-4095(199906)11:8<605::AID-ADMA605>3.0.CO
[7]  
2-Q
[8]   Conjugated organic molecules on metal versus polymer electrodes: Demonstration of a key energy level alignment mechanism [J].
Koch, N ;
Kahn, A ;
Ghijsen, J ;
Pireaux, JJ ;
Schwartz, J ;
Johnson, RL ;
Elschner, A .
APPLIED PHYSICS LETTERS, 2003, 82 (01) :70-72
[9]   THEORY OF METAL SURFACES - WORK FUNCTION [J].
LANG, ND ;
KOHN, W .
PHYSICAL REVIEW B, 1971, 3 (04) :1215-&
[10]   Energy level alignment at Alq/metal interfaces [J].
Lee, ST ;
Hou, XY ;
Mason, MG ;
Tang, CW .
APPLIED PHYSICS LETTERS, 1998, 72 (13) :1593-1595