Controlling energy level offsets in organic/organic heterostructures using intramolecular polar bonds

被引：54

作者：

Duhm, Steffen ^{[1
]}

Salzmann, Ingo ^{[1
]}

Heimel, Georg ^{[1
]}

Oehzelt, Martin ^{[2
]}

Haase, Anja ^{[3
]}

Johnson, Robert L. ^{[4
]}

Rabe, Juergen P. ^{[1
]}

Koch, Norbert ^{[1
]}

机构：

[1] Humboldt Univ, Inst Phys, D-12489 Berlin, Germany

[2] Johannes Kepler Univ Linz, Inst Expt Phys, A-4040 Linz, Austria

[3] Inst Nanostruct Mat & Photon, Joanneum Res Forsch Gesell mbH, A-8160 Weiz, Austria

[4] Univ Hamburg, Inst Expt Phys, D-22761 Hamburg, Germany

来源：

APPLIED PHYSICS LETTERS | 2009年 / 94卷 / 03期

关键词：

bonds (chemical); interface states; organic compounds; organic semiconductors; semiconductor heterojunctions; silicon compounds; ultraviolet photoelectron spectra; THIN-FILMS; INTERFACES; PENTACENE; ALIGNMENT; PERFLUOROPENTACENE; ORIENTATION;

D O I：

10.1063/1.3073046

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The impact of intramolecular polar bonds (IPBs) on the energy level alignment in layered systems of rodlike conjugated molecules standing on the substrate was investigated for pentacene (PEN) and perfluoropentacene (PFP) on SiO(2) using ultraviolet photoelectron spectroscopy. A remarkably large energy offset of 1.75 eV was found between the highest occupied molecular orbital (HOMO) levels of PEN and PFP caused by IPBs at the surface of standing PFP layers. This large HOMO-level offset results in a narrow intermolecular energy gap of approximately 0.4 eV at the interface between PEN and PFP layers. However, the absence of significant spatial overlap of PEN and PFP electron wave functions across the layers suppresses interlayer optical transitions.

引用

页数：3

共 22 条

[1] Low-temperature scanning tunneling microscopy and near-edge X-ray absorption fine structure investigations of molecular orientation of copper(II) phthalocyanine thin films at organic heterojunction interfaces [J].