Bottom-up It starts with atoms, molecules and nano-particle to build up nanostructures with dimensions between 2 and 10 nanometers- and do so inexpensively. Carbon nanotube The structure of the buckball comprised of 60 carbon atoms arranged by 20 hexagonal and 12 pentagonal faces to form a sphere, when the buckyball is enlonged to form a long and narrow tube with a diameter of approximately 1 nm, which is the basic form of a carbon nanotube. Conjugated polymers Conjugated polymers are polyunsat-urated compounds in which all backbone atoms are sp- or sp2-hybridized. Conjugated polymers are -in their pristine, neutral state- either insulators or wide-gap semiconductors, and some of them turn into metallic type conductors only after a process called doping.

Lift-off This patterning approach is called by us "lift-off" since lift-off acts as a critical step in the process. At the beginning, photoresist is spinned on silicon wafer and got patterned. Then nanoparticles are deposited with layer-by-layer assembly on the whole wafer. Eventually, the wafer is put into acetone solution to dissolve resist and particles self-assembled on it are removed, too. Metal mask method This patterning approach is called "metal mask". At first, a layer of nanoparticles are adsorbed onto silicon wafer. Then a layer of aluminum and resist are deposited and coated on top of nanoparticle layer. Patterns are made on resist by UV lithography and transferred to aluminum layer by etching aluminum. As a result, nanoparticles previously covered under aluminum begins to be open to the air. Then it is etched by oxygen plasma and nanoparticles are removed in compliance with the designed patterns. During the etching process, metal acts as the mask over the nano-particles. After remained aluminum and resist are dissolved, only the desired pattern is left on the substrate. Microcontact printing (^CP) Microcontact printing is a flexible, non-photolithographic method that routinely forms patterned SAMs containing regions terminated by different chemical functionalities with submicron lateral dimensions. Microemulsions Microemulsions are thermodynamically stable systems (usually in the size range of 5-50 nm). Nano self-assembly A layer-by-layer (LbL) assembly of alternating layers of oppositely charged polyelectrolytes and nanoparticles provides the formation of 5-500 nm thick films with monolayers of various substances growing in a preset sequence on any substrates at a growth step of about 1 nm. This technique was called "molecular beaker epitaxy" meaning by this that with simple instruments (exploiting the materials self-assembly tendency) one can get molecu-larly organized films similar to the ones obtained with highly sophisticated and expensive molecular beam epitaxy technology for metals and semiconductors. PBG crystal (or photonic crystal) A PBG crystal (or photonic crystal) is a spatially periodic structure fabricated from materials having different dielectric material constants [246]. It can influence the propagation of electromagnetic waves in a similar way as a semiconductor does for electrons. Poly(dimethylsiloxane) (PDMS) elastomers (or silicone rubbers) Used in most demonstrations. Poly(dimethyl-siloxanes) have a unique combination of properties resulting from the presence of an inorganic siloxane backbone and organic methyl groups attached to silicon. These liquid materials can be poured over a master having a relief structure on its surface, then easily converted into solid elastomer by curing and peeling off PDM. Spin assembly Spin-assembly is a specialized application of spin coating, in which a polyelectrolyte multilayered thin film is self-assembled onto a spinning substrate.

Top-down Top-down lithography, they begin with pattern generated on a larger scale and reduce its lateral dimensions.

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