Nanoimprint lithography: an alternative nanofabrication approach

Production of structures for microfluidics using polymer imprint techniques

“…The polymer was placed onto an unstructured piece of the material used to produce the master stamp, positioned on the base of the nanoimprinter. The master was placed on top of the polymer, again with the surface to be embossed in contact with the polymer and the imprinting proceeds in a fashion similar to that used for hot embossing [12]. A schematic diagram of the hot embossing/nanoimprinting process is given in figure 1b, and typical replication conditions for each polymer are given in table I.…”

Transparent micro‐ and nanopatterned poly(lactic acid) for biomedical applications

“…Nanoembossing is the preferred fabrication method to produce these structures because of its excellent resolution, which allows the production of structures with dimensions down to the nanometer range, and replication capabilities, which also points to the possibility of large-area and/or high-volume manufacture. 12 The advantage of using the nanoembossing system is that the structures that can be produced approach dimensions comparable with biological macromolecules; much smaller than the size of an individual cell. Hence, the effect of local interactions of these structures with a cell surface can be examined.…”

Nanostructures Replicated by Polymer Molding

“…Repeated use of a master actually lowers the density of defects in the replica. [46] The advantages of step-and-flash imprint lithography are that: 1) it is a room-temperature technique and is therefore not subject to thermal-or pressure-induced deformations of the nanostructures; 2) it is a rapid process (< 5 min/cycle); [40,47] and 3) it uses optically transparent masters that permit alignment of the replica with underlying features. The disadvantages are that: 1) the masters are more difficult to prepare than those used in soft lithography; 2) the replication of nonplanar masters is difficult; [48] and 3) the technique is not good for the replication of isolated, recessed features in the master.…”

“…The fidelity of replication of nanostructures with critical dimensions of less than 50 nm is poor over large areas because the polymer chains in the materials used in the replicas tend to relax and spread over distances of tens of nanometers. [47] These factors can only be corrected by designing the original master to account for polymer shrinkage in the processing steps. Another disadvantage of nanoimprinting is that it requires 10-15 min per replication for the heating and cooling cycles; this interval is 3-5 times longer than that necessary for the entire replication process for step-and-flash imprint lithography and some soft lithographic techniques.…”