Method for fabricating nanostructures via nanotemplates using dip-pen nanolithography

Abstract

Dip-pen nanolithography (DPN) relies on the compatibility between the ink used and the substrate it is written on. This has lead to a significant reliance for DPN on thiol-gold chemistries for the fabrication of nanostructures. This reported work demonstrates a method for creating nanostructures through nanotemplates that allows a wider range of substrates and inks to be used. The substrate was spin-coated with a thin layer of polymer which is selectively removed using a scanning probe microscopy tip coated with a solvent. This produces nanotemplates that are subsequently used to create nanostructures by metallisation. Compared with directly written templates these nanotemplates facilitate longer interaction between inking material and the substrate. They also allow a controlled spatial resolution along the z-axis and eliminate the need for any blocking agents to prevent non-specific adsorption. This method allows DPN to be expanded to applications beyond thiol-gold chemistries.

Dip-pen patterning of poly(9,9-dioctylfluorene) chain-conformation-based nano-photonic elements

“…For example, direct writing of conducting polymer solution inks produces conductive feature sizes down to ~600 nm on substrates including polyethylene terephthalate and polydimethylsiloxane 21 , and composite inks comprising a pre-polymer carrier fluid and a starburst oligofluorene truxene molecule can be cured after deposition to generate arrays of fluorescent microdomes on silica on silicon substrates 22 . An alternative approach is to use DPN inks to etch patterns into a polymer resist that then acts as a template for metal nanostructure fabrication 23 .…”

“…Our approach to the formation of β-phase patterns on sub-micron length scales is based on a novel DPN strategy, in which a liquid solvent is used as ink. Unlike the conventional DPN techniques 21 22 23 , here a small amount of the solvent ink only temporarily resides in contact with the polymer film. The accompanying swelling of the film assists a fraction of chain segments to adopt the β-phase conformation.…”

Scaling advantages and constraints in miniaturized capture assays for single cell protein analysis

“…In order to do so, a technique called dip-pen nanolithography (DPN) is used and can achieve significantly smaller print features. [8][9][10] Conceptually, there is little difference between conventional microarrayers and DPN -both involve the physical deposition of a solution from a reservoir onto a solid substrate using solid pins, however, DPN uses atomic force microscopy style cantilevers to produce smaller spots.…”