Nanolithography dip-pen

The dip-pen nanolithography technique allows directly printing a wide variety of biomaterials including DNA, phospholipids, and proteins with a resolution below 50 nm (94-96). 

Parallel dip-pen nanolithography arrays have been developed that have substantially increased the throughput of dip-pen nanolithography. In addition, structures of different materials can be simultaneously generated. Therefore, nanoarrays with unprecedented chemical and biochemical complexity can be fabricated (97). 

Pens can be independently addressed within one- or two-dimensional arrays with chemically distinct inks via an inkjet printer (95,96). Multiplexed inking of two-dimensional arrays with multiple fluorophore labeled phospholipids has been successfully tested. 

Controlled patterning of conducting polymers at a micro- or nanoscale is the first step towards the fabrication of miniaturized functional devices. 

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Cacialli, R. H. Friend, Molecular-scale interface engineering for polymer light-emitting diodes, Nature 2000, 404, 481. 

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Figure 13.2 Fluorescence micrographs of DOPC multi-layer patterns fabricated by dip-pen nanolithography, (a) An array of 25 contiguous line features. Red color is from doped rhodamine-labeled lipid, (b) A higher magnification of the region highlighted by the white square in (a), (c) Two-component patterns containing two different dyes. Green color is from doped NBD-labeled lipid.

Figure 25. Formation of an artificial structure of metal nanoparticles by dip pen nanolithography using an AFM (a), tip to transport functionalized thiol molecules onto a gold surface (b) and to trap the nanoparticles (c).

Fig. 2 A quantum dot transport structure, consisting of a source, a drain, and a gate, with gold nanoparticles surrounded by DNA (the bright white dots). The transport through these structures can be fitted well to a simple Coulomb blockade limit description. From S.-W. Chung et al. Top-Down Meets Bottom-Up Dip-Pen Nanolithography and DNA-Directed Assembly of Nanoscale Electrical Circuits Small (2005) 1, 64-69. Copyright Wiley-VCH Verlag GmbH Co. KGaA. Reproduced with permission...

For direct patterning on the nanometer scale, scanning probe microscopy (SPM) based techniques such as dip-pen-nanolithography (DPN), [112-114] nanograftingf, nanoshaving or scanning tunneling microscopy (STM) based techniques such as electron induced diffusion or evaporation have recently been developed (Fig. 9.14) [115, 116]. The SPM based methods, allows the deposition of as-sembhes into restricted areas with 15 nm linewidths and 5 nm spatial resolution. Current capabihties and future applications of DPN are discussed in Ref. [117]. 

DNA arrays have been also generated by Dip-Pen Nanolithography (DPN) [80]. DPN involves the transfer of NAs directly from a coated Atomic Force Microscope (AFM) tip to the substrate of interest by virtue of direct molecular diffusion. Using this technique, thiol-modified ONDs have been patterned onto gold substrates and acrylamide-modified ONDs onto glass sHdes that were previously modified with mercaptopropyltrimethoxysilane. Feature sizes ranging from many micrometers to less than 100 nanometers could be obtained. The deposition of two different OND sequences onto the same substrate has also been reported [80], but the appHcation of this principle to the fabrication of high-density arrays remains to be addressed. 

Controlled delivery of collections of molecules onto a substrate with nanometre resolution can be achieved with the tip of an AFM. This positive printing mode technique is called dip-pen nanolithography (DPN) and its working principle is illustrated in Fig. 3.27. DPN uses an AFM tip as a nanopencil, a substrate as the paper and molecules with a chemical affinity for the substrate as the ink. Capillary transport of molecules from the AFM tip to the solid substrate is used in DPN to directly write patterns consisting of a relatively small collection of molecules in submicrometre dimensions. The hrst example introducing the technique was the transfer of octadecanethiol onto gold surfaces (Piner et al, 1999). 

Dip-pen nanolithography (Jiang and Stupp 2005) and soft lithography (Hung and Stupp 2007) have been used to control the placement and orientation of PA nanofibers on two-dimensional substrates. The soft lithographic technique is the more... 

Lee, M., et al. (2006) Protein nanoarray on Profinker sirrface constructed by atomic force microscopy dip-pen nanolithography for analysis of protein interaction. Proteomics. 6, 1094-103. 

Dip-pen nanolithography (DPN) is a variety of scanning probe lithography (direct-write) developed by Mirkin and coworkers, where components of interest are transferred from an AFM tip to a substrate.201 DPN has been used to pattern a wide variety of materials on surfaces, including small organic molecules (most commonly n-alkanethiols), DNA, nanoparticles, proteins, viruses, and precursors for inorganic thin films. 

The application of scanning probe lithography (SPL) has been widespread owing to its ability to modify substrates with very high resolution and ultimate pattern flexibility.96 Dip-pen nanolithography (DPN),97 high contact force AFM,98 and constructive nanolithography99 are some of the most commonly employed techniques, all of which aim to control the position and directed assembly of molecules and nanoparticles. 

Figure 14.18 Dip-pen nanolithography.122 The thiol ink is transferred from the tip to the gold substrate through the water meniscus between the tip and the substrate according to the direction of scan.

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