Nanopatterning

The nanopatterning of a surface is, however, only the first step toward a surface template. We will further need a specific property of the surface, which is encoded into the pattern. Only this will assure that the template will control the subsequent nucleation or growth processes. In many cases, this specific property will be... 

Recent developments in polymer chemistry have allowed for the synthesis of a remarkable range of well-defined block copolymers with a high degree of molecular, compositional, and structural homogeneity. These developments are mainly due to the improvement of known polymerization techniques and their combination. Parallel advancements in characterization methods have been critical for the identification of optimum conditions for the synthesis of such materials. The availability of these well-defined block copolymers will facilitate studies in many fields of polymer physics and will provide the opportunity to better explore structure-property relationships which are of fundamental importance for hi-tech applications, such as high temperature separation membranes, drug delivery systems, photonics, multifunctional sensors, nanoreactors, nanopatterning, memory devices etc. 

Milliron, D. I Raoux, S. Shelby, R. M. Jordan-Sweet, J. 2007. Solution-phase deposition and nanopatterning of GeSbSe phase-change materials. Nature Mater. 6 352-356. 

The use of block copolymers to form a variety of different nanosized periodic patterns continues to be an active area of research. Whether in bulk, thin film, or solution micelle states, block copolymers present seemingly unlimited opportunities for fabricating and patterning nanostructures. The wealth of microstructures and the tunability of structural dimensions make them a favorable choice for scientists in a variety of research fields. As reviewed here, they can function as nano devices themselves, or act as templates or scaffolds for the fabrication of functional nanopatterns composed of almost all types of materials. However, there are still two obvious areas which require more work control of the long-range 3D nanostructure via more user-friendly processes and the identification of new materials with different functional properties. 

In order to achieve improved nanofabrication performance, novel functional block copolymer systems are strongly desired. Many researchers have recognized this, and novel functional systems such as metal-containing block copolymer systems have significantly simplified and improved nanofabrication processes. The combination of top-down microscale patterns with the bottom-up nanopatterns are attractive for integrating functional nanostructures into multipurpose on-chip devices. However, in order to use these materials in real-time applications, further development is still needed. More ground-shaking discoveries are needed and are also fully expected. 

Fig. 9.31 a) Synthesis of PS-b-polyacrylate brushes by LCSIP and consecutive ATRSIP [282]. AFM images of the tethered PS-fa-PMMA brushes with 23 nm thick PS layer and 14 nm thick PMMA layer b) after treatment with CH2CI2, c) with cyclohexane and d) after solvent exchange from CHjClj to cyclohexane, e) Cartoon proposing a model for the regular nanopattern morphology ( pinned micelles )... 

Schemes Speculative model for nanopattern formation from tethered Si/Si02//PS-l)-PMMA...

The bonding of phosphonic acids to Si02 surfaces has also been reported in an organic solvent, Si-O-P bonds are formed by Si-OH/P-OH condensation [159] however, in an aqueous medium, no bonding was observed [127]. This behavior, which may be ascribed to the sensitivity of Si-O-P bonds to hydrolysis, has been utihzed for the micro- and nanopatterning of surfaces by selective surface modification of Ti02 patterns within a matrix ofSiOz [128]. 

In recent times the incorporation of enzymes into nanostructured materials is commonly referred to as nanobiocatalysis. Nanobiocatalysis has emerged as a rapidly growing research and development area. Lately, nanobiocatalytic approaches have evolved beyond simple enzyme immobilization strategies to include also topics like artificial enzymes and cells, nanofabrication, and nanopatterning [18]. A recent bibliometric analysis [19] of nanobiocatalysis publications shows a strong increase within the last decade (Fig. 14.1). The analysis has been compiled from... 

D. Mandler, Micro- and nanopatterning using the scanning electrochemical microscope. In A.J. Bard and M.V. Mirkin (Eds.), Scanning Electrochemical Microscopy, Marcel Dekker, New York, Basel, 2001, pp. 593-627. 

Ito H, Reichmanis E, Nalamasu O, Ueno T (eds) (1998) Micro- and nanopatterning polymers. ACS Symposium Series 706. American Chemical Society, Washington DC... 

The first volume contains review articles on electric field-induced effects on block copolymer microdomains (by H. Schoberth, V. Olszowka, K. Schmidt, and A. Boker) on experiments and simulations of the nanopattern evolution in block... 

Fig. 1 Nanopatterned surface bearing thermoresponsive elastin-like polypeptides (ELP) allowing reversible capture and release of fusion proteins left ELP switch off center ELP switch on right AFM image of a 10 x 9 ELP dot array in PBS at room temperature. Reprinted, with permission, from [32]. Copyright (2004) American Chemical Society...

Wolfram T, Spatz JP, Burgess RW (2008) Cell adhesion to agrin presented as a nanopatterned substrate is consistent with an interaction with the extracellular matrix and not transmembrane adhesion molecules. BMC Cell Biol 9 64... 

Arnold M, Cavalcanti-Adam EA, Glass R et al (2004) Activation of integrin function by nanopatterned adhesive interfaces. Chemphyschem 5 383-388... 

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