Optical absorption in AlQ

被引：31

作者：

Aziz, A ^{[1
]}

Narasimhan, KL ^{[1
]}

机构：

[1] Tata Inst Fundamental Res, Natl Ctr Govt India Nucl Sci & Math, Bombay 400005, Maharashtra, India

来源：

SYNTHETIC METALS | 2000年 / 114卷 / 02期

关键词：

photothermal deflection spectroscopy; sub-bandgap states; tris(8-hydroxyquinoline)aluminium; optical absorption;

D O I：

10.1016/S0379-6779(00)00232-0

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In this paper, we report on optical absorption in thin films of tris(8-hydroxyquinoline)aluminium (A1Q) between 0.7 and 5 eV. We report on the first measurement of the sub-bandgap absorption in A1Q using Photothermal Deflection Spectroscopy (PDS) for different deposition conditions. The sub-bandgap absorption is not very sensitive to sample deposition temperature but increases on exposure to atmosphere. We present a simple model to explain the absorption data. We calculate the density of states in the gap to be about 6.10(17)/cm(3) and present evidence that the fermi level lies in the upper half of the band gap close to the LUMO level in A1Q. (C) 2000 Elsevier Science S.A. All rights reserved.

引用

页码：133 / 137

页数：5

共 12 条

[1]

AMER NM, 1984, SEMICONDUCT SEMIMET, V21, P83

[2] ABSENCE OF DIFFUSION IN CERTAIN RANDOM LATTICES [J].

ANDERSON, PW .

PHYSICAL REVIEW, 1958, 109 (05) :1492-1505

[3]

AZIZ A, 1999, 11 INT WORKSH PHYS S, P1341

[4] LIGHT-EMITTING-DIODES BASED ON CONJUGATED POLYMERS [J].

BURROUGHES, JH ;

BRADLEY, DDC ;

BROWN, AR ;

MARKS, RN ;

MACKAY, K ;

FRIEND, RH ;

BURN, PL ;

HOLMES, AB .

NATURE, 1990, 347 (6293) :539-541

[5] Trap states of tris-8-(hydroxyquinoline) aluminum and naphthyl-substituted benzidine derivative using thermally stimulated luminescence [J].

Forsythe, EW ;

Morton, DC ;

Tang, CW ;

Gao, YL .

APPLIED PHYSICS LETTERS, 1998, 73 (11) :1457-1459

[6]

Fritzsche H., 1971, Journal of Non-Crystalline Solids, V6, P49, DOI 10.1016/0022-3093(71)90015-9

[7] Photoluminescence efficiency and absorption of aluminum-tris-quinolate (Alq(3)) thin films [J].

Garbuzov, DZ ;

Bulovic, V ;

Burrows, PE ;

Forrest, SR .

CHEMICAL PHYSICS LETTERS, 1996, 249 (5-6) :433-437

[8]

JAFFE HH, 1962, THEORY APPLICATIONS, P186

[9] ELECTRON AND HOLE MOBILITY IN TRIS(8-HYDROXYQUINALINOLATO-N1,O8) ALUMINUM [J].

KEPLER, RG ;

BEESON, PM ;

JACOBS, SJ ;

ANDERSON, RA ;

SINCLAIR, MB ;

VALENCIA, VS ;

CAHILL, PA .

APPLIED PHYSICS LETTERS, 1995, 66 (26) :3618-3620

[10] Ion-beam-induced surface damages on tris-(8-hydroxyquinoline) aluminum [J].

Liao, LS ;

Hung, LS ;

Chan, WC ;

Ding, XM ;

Sham, TK ;

Bello, I ;

Lee, CS ;

Lee, ST .

APPLIED PHYSICS LETTERS, 1999, 75 (11) :1619-1621

← 1 2 →