Thin self-organized patterning

Poly(ferrocenylsilane) polyions are readily processed to novel, fully organometallic multilayer thin films. Furthermore, these organometaUic polyions, featuring a hydrophobic backbone, enable one to make use of both electrostatic and hydrophobic interactions to fabricate self-organized patterns on templated substrates, with potential applications as aqueous pro-cessable ultrathin etch resists. 

Reconstructed clean metal surfaces may thus be interesting templates. However, their given structure does not provide the experimentalist with a control on the nature and physical dimensions of the nanostructure. This implies that these surfaces can be suitable candidates for the investigation of the basic properties of templates on an atomic scale but are less interesting in terms of appHcations. To overcome this limitation systems are needed for which the pattern formation by self-organization can to some extent be controlled by the experimentaUst. This leads us to two promising systems stepped metal surfaces and thin films on metal surfaces. 

Hermes S, Schroder E, Chehnowski R, WoU C, Eischer RA. Selective nucleation and growth of metal-organic open framework thin films on patterned COOH/CEj-terminated self-assembled monolayers on Au(lll). J Am Chem Soc 2005 127(40) 13744-13745. 

If the concentration is low, rather than thin films dissipative structures (e.g., convection patterns, fingering instabilities) are produced [87]. Such work was subsequently used to topographically control neurite extension on stripe-patterned polymer films [150], fabrication of periodic micro-structured honeycomb films having multiple periodicities, and polymer nanoparticles [151]. Large-scale ordering was observed. This was defined by the periodic thickness modulation of a block-copolymer film due to the self-organization of the receding contact line [152]. 

Kargupta, K., Sharma, A. Morphological self-organization by dewetting in thin films on chemically patterned substrates. J. Chem. Phys. 116, 3042-3051 (2002)... 

The inherent ability of block copolymers to self-assemble into various well-ordered supramolecular structures makes them attractive for numerous technological applications. For instance, thin films self-assembled from block copolymers have been used as building blocks in nanotechnology and materials science [89-91 ]. Block copolymers have been employed directly without further manipulation as nanomaterials [92], or used as self-organized templates for the creation of nanos-tructured materials [92, 93]. Block copolymer blends demonstrated their applicability as patterning templates for the fabrication of well-ordered arrays [94], as well as for nanoscale manufacturing of more complex patterns [95]. The use of amphiphilic block copolymers for templating applications has been reviewed by FOrster [96]. 

Dewetting experiments by Reiter [59-61] and subsequently by many others [62-66, 68-75,92-128,137-164] revealed the morphological evolution, self-organization, and pattern formation in thin polymer films. In most experiments the onset of instability is with the form of an undulation of the film surface (Figure 11.1a) [62] or the appearance of fairly equally sized but random collection of holes (Figure 11.1b) [59,60]. The mean... 

Recently, Pcs organized on surface have been used as molecular probes for the determination of quantum confined effects [207], CoPc molecules form ordered self-assembled monolayers (SAM) on the top of Pb(lll) thin films grown on a Si( 111) substrate with the Pc units lying flat on the surface, as revealed by atomically resolved STM. A close analysis of the STM data revealed that the Pc molecules adsorb and self-assemble on the surface following a thickness-dependent adsorption pattern, which is ultimately related to the quantum size effects of the metal surface. 

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