InSb-TiOPc interfaces: Band alignment, ordering and structure dependent HOMO splitting
2009 (English)In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 603, no 20, 3160-3169 p.Article in journal (Refereed) Published
Thin films of titanyl phthalocyanine (TiOPc) have been adsorbed on InSb(1 1 1) (3 x 3) and InSb(1 0 0) c(8 x 2) surfaces and studied with respect to their electronic structure using photoemission (PES), density functional theory (DFT) and scanning tunneling microscopy (STM). The interface chemical interaction is weak in both cases; no adsorbate induced surface band bending is observed and the energy level alignment across the interface is determined by the original position of the substrate Fermi level and the charge neutrality level of the molecule. Room temperature adsorption results in disordered films on both surfaces. The behaviors after annealing are different; on InSb(1 0 0) well-ordered molecular chains form along and on top of the In-rows, whereas on (1 1 1) no long range order is observed. The disorder leads to intermolecular interactions between the titanyl group and neighboring benzene rings leading to a split of TiOPc HOMO (highest occupied molecular orbital) by as much as 0.8 eV.
Place, publisher, year, edition, pages
2009. Vol. 603, no 20, 3160-3169 p.
InSb, Phthalocyanine, Organic-inorganic semiconductor interface, Scanning tunneling microscopy, Photoelectron spectroscopy, metal-free phthalocyanine, titanyl-phthalocyanine, electronic-structure, copper-phthalocyanine, thin-film, molecular-orientation, ir sensitization, ultrathin films, single-crystal, growth mode
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-18899DOI: 10.1016/j.susc.2009.09.001ISI: 000271179600019OAI: oai:DiVA.org:kth-18899DiVA: diva2:336946
QC 201005252010-08-052010-08-052012-03-23Bibliographically approved