Understanding the electronic structure of metal/SAM/organic-semiconductor heterojunctions

ACS Nano

Volumn 3, Issue 11, 2009, Pages 3513-3520

  Rissner, Ferdinand ^a   Rangger, Gerold M ^a   Hofmann, Oliver T ^a   Track, Anna M ^a   Heimel, Georg ^b   Zojer, Egbert ^a  

^a GRAZ UNIVERSITY OF TECHNOLOGY   (Austria)

^b HUMBOLDT UNIVERSITY   (Germany)

Author keywords

Computational modeling; Density functional theory; Electronic structure processes mechanisms; Metal organic interfaces; Molecular electronics; Monolayers; Organic electronics; Self assembly

Indexed keywords

COMPUTATIONAL MODELING; ELECTRONIC STRUCTURE/PROCESSES/MECHANISMS; ENERGY LEVEL ALIGNMENT; FERMI LEVEL PINNING; HOLE INJECTION; METAL/ORGANIC INTERFACES; ORGANIC ELECTRONICS; ORGANIC LAYERS; ORGANIC SEMICONDUCTOR; SEMICONDUCTOR HETEROJUNCTIONS;

ALIGNMENT; CHARGE TRANSFER; ELECTRON ENERGY LEVELS; ELECTRONIC STRUCTURE; HETEROJUNCTIONS; ION EXCHANGE; MOLECULAR ELECTRONICS; SELF ASSEMBLED MONOLAYERS; SELF ASSEMBLY;

DENSITY FUNCTIONAL THEORY;

EID: 73249136915     PISSN: 19360851     EISSN: 1936086X     Source Type: Journal    
DOI: 10.1021/nn9010494     Document Type: Article

References (47)

1. Baldo, M. A.; Forrest, S. R. Interface-Limited Injection in Amorphous Organic Semiconductors. Phys. Rev. B 2001, 64, 085201.
2. Parker, I. D. Carrier Tunneling and Device Characteristics in Polymer Light-Emitting Diodes. J. Appl. Phys. 1994, 75, 1656-1666.
3. van Woudenbergh, T.; Blom, P. W. M.; Huiberts, J. N. Electro-optical Properties of a Polymer Light-Emitting Diode with an Injection-Limited Hole Contact. Appl. Phys. Lett. 2003, 82, 985-987.
4. Campbell, I. H.; Kress, J. D.; Martin, R. L.; Smith, D. L.; Barashkov, N. N.; Ferraris, J. P. Controlling Charge Injection in Organic Electronic Devices Using Self-Assembled Monolayers. Appl. Phys. Lett. 1997, 71, 3528-3530.
5. Bruner, E. L.; Koch, N.; Span, A. R.; Bernasek, S. L.; Kahn, A.; Schwartz, J. Controlling the Work Function of Indium Tin Oxide: Differentiating Dipolar from Local Surface Effects. J. Am. Chem. Soc. 2002, 124, 3192-3193.
6. Bock, C.; Pham, D. V.; Kunze, U.; Käfer, D.; Witte, G.; Woll, C. Improved Morphology and Charge Carrier Injection in Pentacene Field-Effect Transistors with Thiol-Treated Electrodes. J. Appl. Phys. 2006, 100, 114517-7.
7. Yan, H.; Huang, Q. L.; Cui, J.; Veinot, J. G. C.; Kern, M. M.; Marks, T. J. High-Brightness Blue Light-Emitting Polymer Diodes via Anode Modification Using a Self-Assembled Monolayer. Adv. Mater. 2003, 15, 835-838.
8. Asadi, K.; Gholamrezaie, F.; Smits, E.; Blom, P. W. M.; de Boer, B. Manipulation of Charge Carrier Injection into Organic Field-Effect Transistors by Self-Assembled Monolayers of Alkanethiols. J. Mater. Chem. 2007, 17, 1947-1953.
9. Ishii, H.; Sugiyama, K.; Ito, E.; Seki, K. Energy Level Alignment and Interfacial Electronic Structures at Organic/Metal and Organic/Organic Interfaces. Adv. Mater. 1999, 11, 605-625.
10. Koch, N. Organic Electronic Devices and Their Functional Interfaces. ChemPhysChem 2007, 8, 1438-1455.
11. Heimel, G.; Romaner, L.; Bredas, J. L.; Zojer, E. Interface Energetics and Level Alignment at Covalent Metal-Molecule Junctions: π-Conjugated Thiols on Gold. Phys. Rev. Lett. 2006, 96, 196806.
12. Heimel, G.; Romaner, L.; Bredas, J. L.; Zojer, E. Organic/Metal Interfaces in Self-Assembled Monolayers of Conjugated Thiols: A First-Principles Benchmark Study. Surf. Sci. 2006, 600, 4548-4562.
13. Sushko, M. L.; Shluger, A. L. Intramolecular Dipole Coupling and Depolarization in Self-Assembled Monolayers. Adv. Funct. Mater. 2008, 18, 2228-2236.
14. de Boer, B.; Hadipour, A.; Mandoc, M. M.; van Woudenbergh, T.; Blom, P. W. M. Tuning of Metal Work Functions with Self-Assembled Monolayers. Adv. Mater. 2005, 17, 621-625.
15. Betti, M. G.; Kanjilal, A.; Mariani, C.; Vázquez, H.; Dappe, Y. J.; Ortega, J.; Flores, F. Barrier Formation at Organic Interfaces in a Cu(100) - Benzenethiolate - Pentacene Heterostructure. Phys. Rev. Lett. 2008, 100, 027601-4.
16. Braun, S.; de Jong, M. P.; Osikowicz, W.; Salaneck, W. R. Influence of the Electrode Work Function on the Energy Level Alignment at Organic-Organic Interfaces. Appl. Phys. Lett. 2007, 91, 202108-3.
17. Braun, S.; Salaneck, W. R.; Fahlman, M. Energy-Level Alignment at Organic/Metal and Organic/Organic Interfaces. Adv. Mater. 2009, 21,1450-1472.
18. Azzam, W.; Fuxen, C.; Birkner, A.; Rong, H. T.; Buck, M.; Woll, C. Coexistence of Different Structural Phases in Thio-aromatic Monolayers on Au(111). Langmuir 2003, 19, 4958-4968.
19. Heimel, G.; Romaner, L.; Zojer, E.; Bredas, J.-L. The Interface Energetics of Self-Assembled Monolayers on Metals. Acc. Chem. Res. 2008, 41, 721-729.
20. Heimel, G.; Romaner, L.; Zojer, E.; Bredas, J. L. Toward Control of the Metal-Organic Interfacial Electronic Structure in Molecular Electronics: A First-Principles Study on Self-Assembled Monolayers of-Conjugated Molecules on Noble Metals. Nano Lett. 2007, 7,932.
21. The analysis of the charge rearrangements resulting from the bond formation between systems 1and 2and the Au(111) surface (calculations performed in analogy, for example, to ref 11) displays certain features related to electron accumulation, which are located clearly above the head groups. Their origin is not yet fully understood, but intensive tests have shown that they do not depend on the input parameters of the band structure calculations. A consequence of these features is that the obtained work function modifications of -4.06 and-3.86 eV for 1and 2have to be regarded as a lower limit to the actual values. Moreover, the charge rearrangements at the SAM||2P interface are qualitatively consistent with the situations observed for all other SAMs. Consequently, we are confident that these issues bear no relevance for the conclusions drawn in the current paper.
22. SAM.
23. Charbonneau, G. P.; Delugeard, Y. Biphenyl: Three-Dimensional Data and New Refinement at 293 K. Acta Crystallogr., Sect. B 1977, 33, 1586-1588.
24. Koller, G.; Berkebile, S.; Krenn, J. R.; Netzer, F. P.; Oehzelt, M.; Haber, T.; Resel, R.; Ramsey, M. G. Heteroepitaxy of Organic-Organic Nanostructures. Nano Lett. 2006, 6, 1207-1212.
25. Käfer, D.; Ruppel, L.; Witte, G. Growth of Pentacene on Clean and Modified Gold Surfaces. Phys. Rev. B 2007, 75, 085309-14.
26. Oehzelt, M.; Koller, G.; Ivanco, J.; Berkebile, S.; Haber, T.; Resel, R.; Netzer, F. P.; Ramsey, M. G. Organic Heteroepitaxy: p-Sexiphenyl on Uniaxially Oriented α-Sexithiophene. Adv. Mater. 2006, 8, 2466-2470.
27. Crispin, A.; Crispin, X.; Fahlman, M.; Berggren, M.; Salaneck, W. R. Transition between Energy Level Alignment Regimes at a Low Band Gap Polymer-Electrode Interfaces. Appl. Phys. Lett. 2006, 89, 213503-3.
28. 60/Polymer Interfaces. Adv. Mater. 2007, 19, 4213-4217.
29. Seki, K.; Ito, E.; Ishii, H. Energy Level Alignment at Organic/Metal Interfaces Studied by UV Photoemission. Synth. Met. 1997, 91,137-142.
30. Kahn, A.; Koch, N.; Gao, W. Electronic Structure and Electrical Properties of Interfaces between Metals and π-Conjugated Molecular Fims. J. Polym. Sci., Part B 2003, 41, 2529-2548.
31. Simic-Milosevic, V.; Heyde, M.; Lin, X.; Konig, T.; Rust, H.-P.; Sterrer, M.; Risse, T.; Nilius, N.; Freund, H.-J.; Giordano, L.; Pacchioni, G. Charge-Induced Formation of Linear Au Clusters on Thin MgO Films: Scanning Tunneling Microscopy and Density-Functional Theory Study. Phys. Rev. B 2008, 78, 235429-6.
32. Braun, S.; Osikowicz, W.; Wang, Y.; Salaneck, W. R. Energy Level Alignment Regimes at Hybrid Organic-Organic and Inorganic-Organic Interfaces. Org. Electron. 2007, 8, 14-20.
33. Braun, S.; Salaneck, W. R. Fermi Level Pinning at Interfaces with Tetrafluorotetracyanoquinodimethane (F4-TCNQ): The Role of Integer Charge Transfer States. Chem. Phys. Lett. 2007, 438, 259-262.
34. Tengstedt, C.; Osikowicz, W.; Salaneck, W. R.; Parker, I. D.; Hsu, C.-H.; Fahlman, M. Fermi-Level Pinning at Conjugated Polymer Interfaces. Appl. Phys. Lett. 2006, 88, 053502-3.
35. Fahlman, M.; Crispin, A.; Crispin, X.; Henze, S. K. M.; de Jong, M. P.; Osikowicz, W.; Tengstedt, C.; Salaneck, W. R. Electronic Structure of Hybrid Interfaces for Polymer-Based Electronics. J. Phys.: Condens. Matter 2007, 19, 183202.
36. Vázquez, H.; Flores, F.; Kahn, A., Induced Density of States Model for Weakly-Interacting Organic Semiconductor Interfaces. Org. Electron. 2007, 8, 241-248.
37. Vázquez, H.; Oszwaldowski, R.; Pou, P.; Ortega, J.; Perez, R.; Flores, F.; Kahn, A. Dipole Formation at Metal/PTCDA Interfaces: Role of the Charge Neutrality Level. Europhys. Lett. 2004, 65, 802-808.
38. Vázquez, H.; Gao, W.; Flores, F.; Kahn, A. Energy Level Alignment at Organic Heterojunctions: Role of the Charge Neutrality Level. Phys. Rev. B 2005, 71, 041306.
39. Kresse, G.; Furthmuller, J. Efficient Iterative Schemes for Ab Initio Total-Energy Calculations Using a Plane-Wave Basis Set. Phys. Rev. B 1996, 54, 11169-11186.
40. Kresse, G.; Joubert, D. from Ultrasoft Pseudopotentials to the Projector Augmented-Wave Method. Phys. Rev. B 1999, 59, 1758-1775.
41. Monkhorst, H. J.; Pack, J. D. Special Points for Brillouin-Zone Integrations. Phys. Rev. B 1976, 13, 5188-5192.
42. Methfessel, M.; Paxton, A. T. High-Precision Sampling for Brillouin-Zone Integration in Metals. Phys. Rev. B 1989, 40, 3616-3621.
43. Kokalj, A. Comput. Mater. Sci. 2003, 28, 155; code available from http://www.xcrysden.org/.
44. Neaton, J. B.; Hybertsen, M. S.; Louie, S. G. Renormalization of Molecular Electronic Levels at Metal-Molecule Interfaces. Phys. Rev. Lett. 2006, 97, 216405-4.
45. Kubatkin, S.; Danilov, A.; Hjort, M.; Cornil, J.; Bredas, J.-L.; Stuhr-Hansen, N.; Hedegard, P.; Bjornholm, T. Single-Electron Transistor of a Single Organic Molecule with Access to Several Redox States. Nature 2003, 425, 698-701.
46. Norsko, J. K. Chemisorption on Metal Surfaces. Rep. Prog. Phys. 1990, 53, 1253-1295.
47. Newns, D. M. Self-Consistent Model of Hydrogen Chemisorption. Phys. Rev. 1969, 178, 1123.