Top-down patterning

In this review, we describe the recent developments of chemically directed self-assembly of nanoparticle structures on surfaces. The first part focuses on the chemical interactions used to direct the assembly of nanoparticles on surfaces. The second part highlights a few major top-down patterning techniques employed in combination with chemical nanoparticle assembly in manufacturing two- or three-dimensional nanoparticle structures. The combination of top-down and bottom-up techniques is essential in the fabrication of nanoparticle structures of various kinds to accommodate the need for device applications. 

In device fabrication, the location of functional materials is as important as their properties. The integration of solid particles into devices usually requires placing them in specific positions. Hence, the combination of top-down patterning techniques and bottom-up self-assembly is crucial in obtaining (submicron) patterned functional nanostructures on surfaces. 

The channel length defined by the SAP technique is not defined by a top-down patterning step, i.e. the gap dimensions are not known a priori. We have used a range of metrology tools to resolve and determine the channel dimensions defined... 

The dynamic,s underlying EINSTein is patterned after mobile CA rules, and are somewhat reminiscent of Braitenberg s Vehicles [brait84]. Specifically, EINSTein takes a artificial-life-like bottom-up, synthesist approach to the modeling of combat, rather than the more traditional top-down, or reductionist approach,... 

Nanomaterials can be manufactured by one of two groups of methods, one physical and one chemical. In top-down approaches, nanoscale materials are carved into shape by the use of physical nanotechnology methods such as lithography (Fig. 15.30). In bottom-up approaches, molecules are encouraged to assemble themselves into desired patterns chemically by making use of specific... 

Pattern 6.4, Refinement Is a Relation, Not a Sequence Do not make the common mistake of thinking that refinement means top-down development it is a fundamental relation between different descriptions regardless of which one was built first. 

Abstract This article is a review of the chemical and physical nature of patternable block copolymers and their use as templates for functional nanostructures. The patternability of block copolymers, that is, the ability to make complex, arbitrarily shaped submicron structures in block copolymer films, results from both their ability to self-assemble into microdomains, the bottom-up approach, and the manipulation of these patterns by a variety of physical and chemical means including top-down lithographic techniques. Procedures for achieving long-range control of microdomain pattern orientation as well... 

The use of top-down lithographic techniques to topographically pattern substrates and thereby control the film thickness has been used to create submicron patterns that contain oriented microdomains. This approach is generally described as the graphoepitaxy method and will be discussed in further detail in Sect. 4.1, with other methods which use top-down approaches to control the bottom-up block copolymer patterns. 

In addition to the aforementioned methods for controlling substrate-polymer interactions uniformly across the entire surface, the use of top-down lithographic techniques to chemically pattern substrates provides spatial control over these substrate-polymer interactions and therefore provides even... 

Top-Down Lithographic Patterns with Block Copolymer Resist Materials... 

Combination of Top-Down and Bottom-Up Approaches to Give Multilevel Control of Block Copolymer Patterns... 

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