Nanoimprint lithography molds

Nanoimprint lithography Molding of pattern Parallel, fast, no resist, solvents, etc. Large structures, residual chemicals Smaller structures, improved pattern transfer... 

The ability to fabricate nanostructures is essential to modem science and technology [1], Nanoimprint lithography (NIL) in its various forms has demonstrated potential applications in the fabrication of semiconductor devices, microfluidic devices, optical components, photonic devices, replica mold components and biological objects [2],... 

Komuro, M. Hiroshima, H. Kobayashi, K. Miyazaki, T. Ohyi, H. Preparation of diamond mold using electron beam lithography for application to nanoimprint lithography. Jpn. J. Appl. Phys. 1 (Regular Papers Short Notes Review Papers) 2000, 39 (12B), 7070-7074. 

Nanoimprint lithography (NIL) is a relatively new technique designed to produce precisely defined nanoscale features in a parallel, efficient, and cost-effective manner [3,4]. In a typical NIL process, a prepatterned mold is used to press against a resist layer which can go through a thermal plastic transition at an elevated temperature or can be permanently... 

Many of them are based on molding elements (i.e. solid objects with structures of relief on their surfaces) to direct the flow (as in the case of micromolding) or softened solids into the desired shapes. [94-96] The basic one is the embossing technique also referred as nanoimprint lithography (NIL). In this case the mold, made of hard or soft material with specific negative features, is directly pressed against the... 

Fig. 3.16 Embossing or nanoimprint lithography procedure. A hard or soft mold is in contact with surface of a film (a) A pressure is accomplished on the hard mold or a conformal contact is realized for the soft one in order to transfer the features of the mold on the film surface (b) sometimes at this stage a thermal treatment is necessary in order to soften the film and allow abetter transfer of the patterning. Mold is removed (c) A final etching process can be performed to reduce the residual layers between the transferred structures (d)...

Roll-to-roll nanoimprint lithography provides a unique solution to these challenges encountered in the conventional wafer-level NIL process. Imprinting in the roll-to-roll process takes place in a narrow region transverse to the moving direction of the substrate and thus requires much smaller force for pattern replication. Also since the mold is in the form of a roller, the mold-sample separation proceeds in a peeling fashion, which requires much less force, and reduces the probability of defect generation. 

Fig. 25 Vertical chain alignment of P3HT within nanostructures produced by nanoimprint lithography (NIL) [97] (a) the nanoimprinting process (b) the chain alignment process induced by NIL, caused by both the material flow and interactions between the alkyl chains of the polymer chain and the hydrophobic surface of the mold cavities and (c, d) ideal chain orientation within...

Using nanoimprint lithography, Kostovski et al. (2009) replicated the nanostructures present on cicada wings onto the end faces of standard silica optical fibers. A PDMS mold was used to transfer the nanofeatures from a cicada wing segment onto the tip of an optical fiber. After the optical... 

Many UV-assisted nanoimprint lithography (UV-NIL) processes, described in the next section, rely on capillary forces to fill the mold, so the distinction of CFL as a separate lithography technique is blurred. 

The thiol-ene imprint resists find use in a form of UV-NIL called nanocontact molding (NCM) imprint lithography, soft step and flash imprint lithography (SSFIL), and soft nanoimprint lithography (SNIL) where sub-100 nm features have been successfully replicated.The mechanical properties and surface chemistries of thiol-ene photopolymers have also been thoroughly investigated. 

Nanoimprint lithography, sometimes called microembossing, has been used in a method similar to graphoepitaxy. " A patterned elastomeric mold is applied to a block copolymer solvent-swollen or melt film, and the block copolymer self-assembly forms within trenches in the mold and aligns to the mold walls after cooling or evaporating the solvent so that block copolymers no longer have mobility, the mold is removed. 

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