Metal—organic interface

Ishii H, Seki K (1997) Energy level alignment at organic/metal interfaces studied by UV photoemission breakdown of traditional assumption of a common vacuum level at the interface. Trans Electron Devices 44 1295-1301... 

By careful examination of the various work dealing with organic-metal interfaces, they concluded the following ... 

The dipolar difference is very complex in organic-metal interfaces (metal may deposit into the organic layer). 

FIGURE 3.3 Schematic of an organic-metal interface energy diagram (a) without and (b) with an interface dipole and (c) UPS spectra of metal and organic. (From Hung, L.S. and Chen, C.H., Mater. Sci. Eng., R39, 143, 2002. With permission.)... 

Many published results on electronic transport properties of organic materials, where metal contacts are usually made by evaporation of metals, do not describe the quality of the organic/metal interface, and some exotic observed features may perhaps be ascribed to extrinsic effects such as metal diffusion. The relatively simple contact lamination technique may become an alternative, since it provides a means for establishing electrical contacts without the potential disruption of the organic material associated with metal evaporation. The method consists in bringing the organic layer into mechanical contact with an elastomeric element coated with a thin metal film, which can also be patterned. The contacts are robust and reversible... 

Rectification phenomena through molecules is attributed to three different effects. The first is due to Schottky barriers because a surface dipole is formed at the organic/metal interface. The second effect occurs when the LUMO... 

Figure 13-7. Principle of the UPS study of an organic/metal interface, (a) Photoemission from the metal (b) photoemission from an organic layer deposited on the metal surface. Reproduced from [115] with permission from Elsevier Science.

K. Mullen, and J. P. Rabe, Influence of molecular conformation on organic/ metal interface energetics, Chem. 

Charge Transfer and Polarization Screening at Organic/Metal Interfaces Single Crystalline Versus Polycrystalline Gold... 

The total temperature difference is 111 - 52 = 59°C The organic/metal interface temperature is 0.000684... 

Debe, M.K. "Organic/Metal Interface Studies with Reflection-Adsorption Infrared Spectroscopy Photomarked Surfactants and Organic Photoconductors on Aluminum", Appli. of Surf. Sci., 14,... 

Crispin, X. (2004) Interface dipole at organic/metal interfaces and organic solar cells . Solar Energy Materials and Solar Cells, 83,147-68. 

Characterization of the interface dipole at organic/metal interfaces. J. Am. Chem. Soc. 124,8131-8141. 

Ishii, H., K. Sugiyama, and K. Seki. 1997. Interfadal electronic stmctures of organic/metal interfaces studied by UV photoemission. SPIE97 Proc (San Diego), pp. 228—237. 

The energy of the highest-occupied molecular orbital (HOMO) should be equal to the negative of the ionization potential (I.P.), but in conventional functionals it is strongly underestimated. This is severe limitation in many applications, e.g. in the description of organic-metal interfaces and for electronic transport calculations.In EXX methods the energy of the HOMO closely reproduced the I.P. (see Section 3.5) ... 

Fig. 9 Energy diagram of the organic-metal interface. VL vacuum level Ep Fermi level of the metal work...

Salaneck WR, Seki K, Kahn A, Pireaux JJ (eds) (2002) Energy level alignment at organic-metal interfaces (Chapter 10). In Conjugated polymer and molecular interfaces. Marcel Dekker, New York... 

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