The Experts below are selected from a list of 1836 Experts worldwide ranked by ideXlab platform

Chad A. Mirkin - One of the best experts on this subject based on the ideXlab platform.

  • Evolution of Dip-Pen Nanolithography (DPN): From Molecular Patterning to Materials Discovery
    Chemical Reviews, 2020
    Co-Authors: Guoqiang Liu, Sarah Hurst Petrosko, Zijian Zheng, Chad A. Mirkin
    Abstract:

    Dip-Pen Nanolithography (DPN) is a nanofabrication technique that can be used to directly write molecular patterns on substrates with high resolution and registration. Over the past two decades, DP...

  • Capillary bridge rupture in Dip-Pen Nanolithography.
    Soft matter, 2014
    Co-Authors: Daniel J. Eichelsdoerfer, Keith A. Brown, Chad A. Mirkin
    Abstract:

    Here, we explore fluid transfer from a nanoscale tip to a surface and elucidate the role of fluid flows in Dip-Pen Nanolithography (DPN) of liquid inks. We find that while fluid transfer in this context is affected by dwell time and tip retraction speed from the substrate, their specific roles are dictated by the contact angle of the ink on the surface. This is shown by two observations: (1) the power law scaling of transferred fluid with dwell time depends on contact angle, and (2) slower retraction speeds result in more transfer on hydrophilic surfaces, but less transfer on hydrophobic surfaces. These trends, coupled with the observation of a transition from quasi-static to dynamic capillary rupture at a capillary number of 6 × 10−6, show that the transfer process is a competition between surface energy and viscosity. Based on this, we introduce retraction speed as an important parameter in DPN and show that it is possible to print polymer features as small as 14 nm. Further explorations of this kind may provide a useful platform for studying capillary phenomena at the nanoscale.

  • Material transport in Dip-Pen Nanolithography
    Frontiers of Physics, 2013
    Co-Authors: Keith A. Brown, Daniel J. Eichelsdoerfer, Xing Liao, Chad A. Mirkin
    Abstract:

    Dip-Pen Nanolithography (DPN) is a useful method for directly printing materials on surfaces with sub-50 nm resolution. Because it involves the physical transport of materials from a scanning probe tip to a surface and the subsequent chemical interaction of that material with the surface, there are many factors to consider when attempting to understand DPN. In this review, we overview the physical and chemical processes that are known to play a role in DPN. Through a detailed review of the literature, we classify inks into three general categories based on their transport properties, and highlight the myriad ways that DPN can be used to perform chemistry at the tip of a scanning probe.

  • Layer-by-layer assembly of a metallomesogen by Dip-Pen Nanolithography.
    ACS Nano, 2013
    Co-Authors: Boya Radha, Daniel J. Eichelsdoerfer, Giridhar U. Kulkarni, Guoliang Liu, Chad A. Mirkin
    Abstract:

    Palladium alkanethiolates are introduced here as a novel liquid ink for Dip-Pen Nanolithography (DPN). These structures exhibit the unusual characteristic of layer-by-layer assembly, allowing one to deposit a desired number of metal ions on a surface, which can subsequently be reduced via thermolysis to form active catalytic structures. Such structures have been used to generate contiguous metallic or conducting polymer nanoscale architectures by electroless deposition.

  • Nanotechnology - Materials Integration by Dip‐Pen Nanolithography
    Nanotechnology, 2010
    Co-Authors: Steven Lenhert, Harald Fuchs, Chad A. Mirkin
    Abstract:

    Dip-Pen Nanolithography (DPN) is a versatile tool for nanotechnology that enables the resolution of electron-beam lithography, integration capabilities typical of inkjet printing, and a high throughput comparable to microcontact printing. By using the tip of an atomic force microscope as an ultra-sharp pen, DPN represents a constructive method of scanning probe lithography that can be carried out in a massively parallel fashion. This chapter introduces the fundamental concepts in DPN technology, with a focus on aspects that enable materials integration. Theoretical models of ink transport are discussed, and a variety of experimental methods presented. The concept of a driving force is explained, along with various methods for controlling that driving force, both by ink–substrate combinations, humidity and the application of external fields. Various approaches to tip coating are explained and suitable characterization methods presented. Finally, examples of unique applications of materials integration by DPN will be described that cannot be achieved by any other method, including templates, combinatorial chemistry and biological arrays. Keywords: Dip-Pen Nanolithography (DPN); scanning probe lithography; ink transport; atomic force microscopy; high throughput; microarrays; nanoarrays; integration; nanotechnology

Zhenan Bao - One of the best experts on this subject based on the ideXlab platform.

  • Dip-Pen Nanolithography of electrical contacts to single graphene flakes
    ACS Nano, 2010
    Co-Authors: Wechung Maria Wang, Nimrod Stander, Randall M. Stoltenberg, David Goldhaber-gordon, Zhenan Bao
    Abstract:

    This study evaluates an alternative to electron-beam lithography for fabricating nanoscale graphene devices. Dip-Pen Nanolithography is used for defining monolayer graphene flakes and for patterning of gold electrodes through writing of an alkylthiol on thin films of gold evaporated onto graphene flakes. A wet gold etching step was used to form the individual devices. The sheet resistances of these monolayer graphene devices are comparable to reported literature values. This alternative technique for making electrical contact to 2D nanostructures provides a platform for fundamental studies of nanomaterial properties. The merits of using Dip-Pen Nanolithography include lack of electron-beam irradiation damage and targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions.

  • dip pen Nanolithography of electrical contacts to single walled carbon nanotubes
    ACS Nano, 2009
    Co-Authors: Wechung Maria Wang, Selvapraba Selvarasah, Melburne C. Lemieux, Mehmet Remzi Dokmeci, Zhenan Bao
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices. This technique enables insight into three key concepts at the nanoscale: using Dip-Pen Nanolithography as an alternative to electron-beam lithography for writing contacts to carbon nanotubes, understanding the integrity of contacts and devices patterned with this technique, and on a more fundamental level, providing a facile method to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was deposited via Dip-Pen Nanolithography on a thin film of Au evaporated onto spin-cast, nonpercolating, and highly isolated single-walled carbon nanotubes. A wet Au etching step was used to form the individual devices. The electrical characteristics...

  • Dip-Pen Nanolithography of Electrical Contacts to Single-Walled Carbon
    2009
    Co-Authors: Nanotubes Maria Wang, Melburne C. Lemieux, Mehmet Remzi Dokmeci, Zhenan Bao
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices.Thistechniqueenablesinsightintothreekeyconceptsatthenanoscale:usingDip-PenNanolithographyas analternativetoelectron-beamlithographyforwritingcontactstocarbonnanotubes,understandingtheintegrity ofcontactsanddevicespatternedwiththistechnique,andonamorefundamentallevel,providingafacilemethod to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was depositedviaDip-Pen Nanolithography on a thinfilm of Au evaporated onto spin-cast, nonpercolating, andhighlyisolatedsingle-walledcarbonnanotubes.AwetAuetchingstepwasusedtoformtheindividualdevices. Theelectricalcharacteristicsforthreedifferentsingle-walledcarbonnanotubedevicesarereported:semimetallic, semiconducting, and metallic. Raman analysis on representative devices corroborates the results from AFM imagingandelectricaltesting.Thisworkdemonstratesatechniqueformakingelectricalcontacttonanostructures of interest and provides a platform for directly corroborating electrical and optical measurements. The merits of using Dip-Pen Nanolithography includeflexible device configuration (such as varying the channel length and the number, size, and orientation of contacts), targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions, and negligible damage to single-walled carbon nanotubes during the fabrication process.

Wechung Maria Wang - One of the best experts on this subject based on the ideXlab platform.

  • Dip-Pen Nanolithography of electrical contacts to single graphene flakes
    ACS Nano, 2010
    Co-Authors: Wechung Maria Wang, Nimrod Stander, Randall M. Stoltenberg, David Goldhaber-gordon, Zhenan Bao
    Abstract:

    This study evaluates an alternative to electron-beam lithography for fabricating nanoscale graphene devices. Dip-Pen Nanolithography is used for defining monolayer graphene flakes and for patterning of gold electrodes through writing of an alkylthiol on thin films of gold evaporated onto graphene flakes. A wet gold etching step was used to form the individual devices. The sheet resistances of these monolayer graphene devices are comparable to reported literature values. This alternative technique for making electrical contact to 2D nanostructures provides a platform for fundamental studies of nanomaterial properties. The merits of using Dip-Pen Nanolithography include lack of electron-beam irradiation damage and targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions.

  • dip pen Nanolithography of electrical contacts to single walled carbon nanotubes
    ACS Nano, 2009
    Co-Authors: Wechung Maria Wang, Selvapraba Selvarasah, Melburne C. Lemieux, Mehmet Remzi Dokmeci, Zhenan Bao
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices. This technique enables insight into three key concepts at the nanoscale: using Dip-Pen Nanolithography as an alternative to electron-beam lithography for writing contacts to carbon nanotubes, understanding the integrity of contacts and devices patterned with this technique, and on a more fundamental level, providing a facile method to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was deposited via Dip-Pen Nanolithography on a thin film of Au evaporated onto spin-cast, nonpercolating, and highly isolated single-walled carbon nanotubes. A wet Au etching step was used to form the individual devices. The electrical characteristics...

  • dip pen Nanolithography of electrical contacts to single walled carbon nanotubes
    ACS Nano, 2009
    Co-Authors: Wechung Maria Wang, Selvapraba Selvarasah, Melburne C Lemieu, Mehmet Remzi Dokmeci
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices. This technique enables insight into three key concepts at the nanoscale: using Dip-Pen Nanolithography as an alternative to electron-beam lithography for writing contacts to carbon nanotubes, understanding the integrity of contacts and devices patterned with this technique, and on a more fundamental level, providing a facile method to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was deposited via Dip-Pen Nanolithography on a thin film of Au evaporated onto spin-cast, nonpercolating, and highly isolated single-walled carbon nanotubes. A wet Au etching step was used to form the individual devices. The electrical characteristics for three different single-walled carbon nanotube devices are reported: semimetallic, semiconducting, and metallic. Raman analysis on representative devices corroborates the results from AFM imaging and electrical testing. This work demonstrates a technique for making electrical contact to nanostructures of interest and provides a platform for directly corroborating electrical and optical measurements. The merits of using Dip-Pen Nanolithography include flexible device configuration (such as varying the channel length and the number, size, and orientation of contacts), targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions, and negligible damage to single-walled carbon nanotubes during the fabrication process.

Mehmet Remzi Dokmeci - One of the best experts on this subject based on the ideXlab platform.

  • dip pen Nanolithography of electrical contacts to single walled carbon nanotubes
    ACS Nano, 2009
    Co-Authors: Wechung Maria Wang, Selvapraba Selvarasah, Melburne C. Lemieux, Mehmet Remzi Dokmeci, Zhenan Bao
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices. This technique enables insight into three key concepts at the nanoscale: using Dip-Pen Nanolithography as an alternative to electron-beam lithography for writing contacts to carbon nanotubes, understanding the integrity of contacts and devices patterned with this technique, and on a more fundamental level, providing a facile method to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was deposited via Dip-Pen Nanolithography on a thin film of Au evaporated onto spin-cast, nonpercolating, and highly isolated single-walled carbon nanotubes. A wet Au etching step was used to form the individual devices. The electrical characteristics...

  • dip pen Nanolithography of electrical contacts to single walled carbon nanotubes
    ACS Nano, 2009
    Co-Authors: Wechung Maria Wang, Selvapraba Selvarasah, Melburne C Lemieu, Mehmet Remzi Dokmeci
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices. This technique enables insight into three key concepts at the nanoscale: using Dip-Pen Nanolithography as an alternative to electron-beam lithography for writing contacts to carbon nanotubes, understanding the integrity of contacts and devices patterned with this technique, and on a more fundamental level, providing a facile method to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was deposited via Dip-Pen Nanolithography on a thin film of Au evaporated onto spin-cast, nonpercolating, and highly isolated single-walled carbon nanotubes. A wet Au etching step was used to form the individual devices. The electrical characteristics for three different single-walled carbon nanotube devices are reported: semimetallic, semiconducting, and metallic. Raman analysis on representative devices corroborates the results from AFM imaging and electrical testing. This work demonstrates a technique for making electrical contact to nanostructures of interest and provides a platform for directly corroborating electrical and optical measurements. The merits of using Dip-Pen Nanolithography include flexible device configuration (such as varying the channel length and the number, size, and orientation of contacts), targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions, and negligible damage to single-walled carbon nanotubes during the fabrication process.

  • Dip-Pen Nanolithography of Electrical Contacts to Single-Walled Carbon
    2009
    Co-Authors: Nanotubes Maria Wang, Melburne C. Lemieux, Mehmet Remzi Dokmeci, Zhenan Bao
    Abstract:

    This paper discusses a method for the direct patterning of Au electrodes at nanoscale resolution using Dip-Pen Nanolithography, with proof-of-concept demonstrated by creating single-walled carbon nanotube devices.Thistechniqueenablesinsightintothreekeyconceptsatthenanoscale:usingDip-PenNanolithographyas analternativetoelectron-beamlithographyforwritingcontactstocarbonnanotubes,understandingtheintegrity ofcontactsanddevicespatternedwiththistechnique,andonamorefundamentallevel,providingafacilemethod to compare and understand electrical and Raman spectroscopy data from the same isolated carbon nanotube. Electrical contacts to individual and small bundle single-walled carbon nanotubes were masked by an alkylthiol that was depositedviaDip-Pen Nanolithography on a thinfilm of Au evaporated onto spin-cast, nonpercolating, andhighlyisolatedsingle-walledcarbonnanotubes.AwetAuetchingstepwasusedtoformtheindividualdevices. Theelectricalcharacteristicsforthreedifferentsingle-walledcarbonnanotubedevicesarereported:semimetallic, semiconducting, and metallic. Raman analysis on representative devices corroborates the results from AFM imagingandelectricaltesting.Thisworkdemonstratesatechniqueformakingelectricalcontacttonanostructures of interest and provides a platform for directly corroborating electrical and optical measurements. The merits of using Dip-Pen Nanolithography includeflexible device configuration (such as varying the channel length and the number, size, and orientation of contacts), targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions, and negligible damage to single-walled carbon nanotubes during the fabrication process.

Harald Fuchs - One of the best experts on this subject based on the ideXlab platform.

  • Ink transport modelling in Dip-Pen Nanolithography and Polymer Pen Lithography
    Nanofabrication, 2016
    Co-Authors: Ainhoa Urtizberea, Michael Hirtz, Harald Fuchs
    Abstract:

    Dip-Pen Nanolithography (DPN) and Polymer pen lithography (PPL) are powerful lithography techniques being able to pattern a wide range of inks. Transport and surface spreading depend on the ink physicochemical properties, defining its diffusive and fluid character. Structure assembly on surface arises from a balance between the entanglement of the ink itself and the interaction with the substrate. According to the transport characteristics, different models have been proposed. In this article we review the common types of inks employed for patterning, the particular physicochemical characteristics that make them flow following different dynamics as well as the corresponding transport mechanisms and models that describe them.

  • Dip-Pen Nanolithography-Assisted Protein Crystallization
    2015
    Co-Authors: Francesco S. Ielasi, Michael Hirtz, Harald Fuchs, Thomas Laue, Sylwia Sekula-neuner, Ronnie Willaert
    Abstract:

    We demonstrate the use of Dip-Pen Nanolithography (DPN) to crystallize proteins on surface-localized functionalized lipid layer arrays. DOPC lipid layers, containing small amounts of biotin-DOPE lipid molecules, were printed on glass substrates and evaluated in vapor diffusion and batch crystallization screening setups, where streptavidin was used as a model protein for crystallization. Independently of the crystallization system used and the geometry of the lipid layers, nucleation of streptavidin crystals occurred specifically on the DPN-printed biotinylated structures. Protein crystallization on lipid array patches is also demonstrated in a microfluidic chip, which opens the way toward high-throughput screening to find suitable nucleation and crystal growth conditions. The results demonstrate the use of DPN in directing and inducing protein crystallization on specific surface locations

  • Dip-Pen Nanolithography-assisted protein crystallization.
    Journal of the American Chemical Society, 2014
    Co-Authors: Francesco S. Ielasi, Michael Hirtz, Harald Fuchs, Thomas Laue, Sylwia Sekula-neuner, Ronnie Willaert
    Abstract:

    We demonstrate the use of Dip-Pen Nanolithography (DPN) to crystallize proteins on surface-localized functionalized lipid layer arrays. DOPC lipid layers, containing small amounts of biotin-DOPE lipid molecules, were printed on glass substrates and evaluated in vapor diffusion and batch crystallization screening setups, where streptavidin was used as a model protein for crystallization. Independently of the crystallization system used and the geometry of the lipid layers, nucleation of streptavidin crystals occurred specifically on the DPN-printed biotinylated structures. Protein crystallization on lipid array patches is also demonstrated in a microfluidic chip, which opens the way toward high-throughput screening to find suitable nucleation and crystal growth conditions. The results demonstrate the use of DPN in directing and inducing protein crystallization on specific surface locations.

  • Multiplexed biomimetic lipid membranes on graphene by Dip-Pen Nanolithography
    Nature communications, 2013
    Co-Authors: Michael Hirtz, Harald Fuchs, Antonios Oikonomou, T. Georgiou, Aravind Vijayaraghavan
    Abstract:

    The application of graphene in sensor devices depends on the ability to appropriately functionalize the pristine graphene. Here we show the direct writing of tailored phospholipid membranes on graphene using Dip-Pen Nanolithography. Phospholipids exhibit higher mobility on graphene compared with the commonly used silicon dioxide substrate, leading to well-spread uniform membranes. Dip-Pen Nanolithography allows for multiplexed assembly of phospholipid membranes of different functionalities in close proximity to each other. The membranes are stable in aqueous environments and we observe electronic doping of graphene by charged phospholipids. On the basis of these results, we propose phospholipid membranes as a route for non-covalent immobilization of various functional groups on graphene for applications in biosensing and biocatalysis. As a proof of principle, we demonstrate the specific binding of streptavidin to biotin-functionalized membranes. The combination of atomic force microscopy and binding experiments yields a consistent model for the layer organization within phospholipid stacks on graphene.

  • Substrate-independent Dip-Pen Nanolithography based on reactive coatings.
    Journal of the American Chemical Society, 2010
    Co-Authors: Hsien-yeh Chen, Michael Hirtz, Harald Fuchs, Xiaopei Deng, Thomas Laue, Joerg Lahann
    Abstract:

    We report that nanostructuring via Dip-Pen Nanolithography can be used for modification of a broad range of different substrates (polystyrene, Teflon, stainless steel, glass, silicon, rubber, etc.) without the need for reconfiguring the underlying printing technology. This is made possible through the use of vapor-based coatings that can be deposited on these substrates with excellent conformity, while providing functional groups for subsequent spatially directed click chemistry via Dip-Pen Nanolithography. Pattern quality has been compared on six different substrates demonstrating that this approach indeed results in a surface modification protocol with potential use for a wide range of biotechnological applications.