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Shani L, Chaaban J, Nilson A, Clerc E, Menning G, Riggert C, Lueb P, Rossi M, Badawy G, Bakkers EPAM, Pribiag VS. Thermal scanning probe and laser lithography for patterning nanowire based quantum devices. NANOTECHNOLOGY 2024; 35:255302. [PMID: 38467064 DOI: 10.1088/1361-6528/ad3257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 03/10/2024] [Indexed: 03/13/2024]
Abstract
Semiconductor nanowire (NW) quantum devices offer a promising path for the pursuit and investigation of topologically-protected quantum states, and superconducting and spin-based qubits that can be controlled using electric fields. Theoretical investigations into the impact of disorder on the attainment of dependable topological states in semiconducting nanowires with large spin-orbit coupling andg-factor highlight the critical need for improvements in both growth processes and nanofabrication techniques. In this work, we used a hybrid lithography tool for both the high-resolution thermal scanning probe lithography and high-throughput direct laser writing of quantum devices based on thin InSb nanowires with contact spacing of 200 nm. Electrical characterization demonstrates quasi-ballistic transport. The methodology outlined in this study has the potential to reduce the impact of disorder caused by fabrication processes in quantum devices based on 1D semiconductors.
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Affiliation(s)
- Lior Shani
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Jana Chaaban
- Heidelberg Instruments Nano AG, Zurich, Switzerland
| | - Alec Nilson
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Eliott Clerc
- Heidelberg Instruments Nano AG, Zurich, Switzerland
| | - Gavin Menning
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Colin Riggert
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Pim Lueb
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Marco Rossi
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Ghada Badawy
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Erik P A M Bakkers
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Vlad S Pribiag
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States of America
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2
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Ramò L, Giordano MC, Ferrando G, Canepa P, Telesio F, Repetto L, Buatier de Mongeot F, Canepa M, Bisio F. Thermal Scanning-Probe Lithography for Broad-Band On-Demand Plasmonic Nanostructures on Transparent Substrates. ACS APPLIED NANO MATERIALS 2023; 6:18623-18631. [PMID: 37854851 PMCID: PMC10580238 DOI: 10.1021/acsanm.3c04398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 09/21/2023] [Indexed: 10/20/2023]
Abstract
Thermal scanning-probe lithography (t-SPL) is a high-resolution nanolithography technique that enables the nanopatterning of thermosensitive materials by means of a heated silicon tip. It does not require alignment markers and gives the possibility to assess the morphology of the sample in a noninvasive way before, during, and after the patterning. In order to exploit t-SPL at its peak performances, the writing process requires applying an electric bias between the scanning hot tip and the sample, thereby restricting its application to conductive, optically opaque, substrates. In this work, we show a t-SPL-based method, enabling the noninvasive high-resolution nanolithography of photonic nanostructures onto optically transparent substrates across a broad-band visible and near-infrared spectral range. This was possible by intercalating an ultrathin transparent conductive oxide film between the dielectric substrate and the sacrificial patterning layer. This way, nanolithography performances comparable with those typically observed on conventional semiconductor substrates are achieved without significant changes of the optical response of the final sample. We validated this innovative nanolithography approach by engineering periodic arrays of plasmonic nanoantennas and showing the capability to tune their plasmonic response over a broad-band visible and near-infrared spectral range. The optical properties of the obtained systems make them promising candidates for the fabrication of hybrid plasmonic metasurfaces supported onto fragile low-dimensional materials, thus enabling a variety of applications in nanophotonics, sensing, and thermoplasmonics.
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Affiliation(s)
- Lorenzo Ramò
- OptMatLab,
Dipartimento di Fisica, Università
di Genova, Via Dodecaneso 33, I-16146 Genova, Italy
| | - Maria Caterina Giordano
- LabNano,
Dipartimento di Fisica, Università
di Genova, Via Dodecaneso
33, I-16146 Genova, Italy
| | - Giulio Ferrando
- LabNano,
Dipartimento di Fisica, Università
di Genova, Via Dodecaneso
33, I-16146 Genova, Italy
| | - Paolo Canepa
- OptMatLab,
Dipartimento di Fisica, Università
di Genova, Via Dodecaneso 33, I-16146 Genova, Italy
| | - Francesca Telesio
- Dipartimento
di Fisica, Università di Genova, Via Dodecaneso 33, I-16146 Genova, Italy
| | - Luca Repetto
- Nanomed
Laboratories, Dipartimento di Fisica, Università
di Genova, Via Dodecaneso
33, I-16146 Genova, Italy
| | | | - Maurizio Canepa
- OptMatLab,
Dipartimento di Fisica, Università
di Genova, Via Dodecaneso 33, I-16146 Genova, Italy
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3
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Howell ST, Grushina A, Holzner F, Brugger J. Thermal scanning probe lithography-a review. MICROSYSTEMS & NANOENGINEERING 2020; 6:21. [PMID: 34567636 PMCID: PMC8433166 DOI: 10.1038/s41378-019-0124-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 11/05/2019] [Accepted: 11/25/2019] [Indexed: 05/08/2023]
Abstract
Fundamental aspects and state-of-the-art results of thermal scanning probe lithography (t-SPL) are reviewed here. t-SPL is an emerging direct-write nanolithography method with many unique properties which enable original or improved nano-patterning in application fields ranging from quantum technologies to material science. In particular, ultrafast and highly localized thermal processing of surfaces can be achieved through the sharp heated tip in t-SPL to generate high-resolution patterns. We investigate t-SPL as a means of generating three types of material interaction: removal, conversion, and addition. Each of these categories is illustrated with process parameters and application examples, as well as their respective opportunities and challenges. Our intention is to provide a knowledge base of t-SPL capabilities and current limitations and to guide nanoengineers to the best-fitting approach of t-SPL for their challenges in nanofabrication or material science. Many potential applications of nanoscale modifications with thermal probes still wait to be explored, in particular when one can utilize the inherently ultrahigh heating and cooling rates.
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Affiliation(s)
- Samuel Tobias Howell
- Microsystems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Anya Grushina
- Heidelberg Instruments Nano - SwissLitho AG, Technoparkstrasse 1, 8005 Zürich, Switzerland
| | - Felix Holzner
- Heidelberg Instruments Nano - SwissLitho AG, Technoparkstrasse 1, 8005 Zürich, Switzerland
| | - Juergen Brugger
- Microsystems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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4
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Fringes S, Schwemmer C, Rawlings CD, Knoll AW. Deterministic Deposition of Nanoparticles with Sub-10 nm Resolution. NANO LETTERS 2019; 19:8855-8861. [PMID: 31693376 DOI: 10.1021/acs.nanolett.9b03687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Accurate deposition of nanoparticles at defined positions on a substrate is still a challenging task, because it requires simultaneously stable long-range transport and attraction to the target site and precise short-range orientation and deposition. Here we present a method based on geometry-induced energy landscapes in a nanofluidic slit for particle manipulation: Brownian motors or electro-osmotic flows are used for particle delivery to the target area. At the target site, electrostatic trapping localizes and orients the particles. Finally, reducing the gap distance of the slit leads sequentially to a focusing of the particle position and a jump into adhesive contact by several nanometers. For 60 nm gold spheres, we obtain a placement accuracy of 8 nm. The versatility of the method is demonstrated further by a stacked assembly of nanorods and the directed deposition of InAs nanowires.
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Affiliation(s)
- Stefan Fringes
- IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland
| | - C Schwemmer
- IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland
| | - Colin D Rawlings
- IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland
| | - Armin W Knoll
- IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland
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5
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Rubin S, Hong B, Fainman Y. Subnanometer imaging and controlled dynamical patterning of thermocapillary driven deformation of thin liquid films. LIGHT, SCIENCE & APPLICATIONS 2019; 8:77. [PMID: 31645923 PMCID: PMC6804570 DOI: 10.1038/s41377-019-0190-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 08/01/2019] [Accepted: 08/05/2019] [Indexed: 06/01/2023]
Abstract
Exploring and controlling the physical factors that determine the topography of thin liquid dielectric films are of interest in manifold fields of research in physics, applied mathematics, and engineering and have been a key aspect of many technological advancements. Visualization of thin liquid dielectric film topography and local thickness measurements are essential tools for characterizing and interpreting the underlying processes. However, achieving high sensitivity with respect to subnanometric changes in thickness via standard optical methods is challenging. We propose a combined imaging and optical patterning projection platform that is capable of optically inducing dynamical flows in thin liquid dielectric films and plasmonically resolving the resulting changes in topography and thickness. In particular, we employ the thermocapillary effect in fluids as a novel heat-based method to tune plasmonic resonances and visualize dynamical processes in thin liquid dielectric films. The presented results indicate that light-induced thermocapillary flows can form and translate droplets and create indentation patterns on demand in thin liquid dielectric films of subwavelength thickness and that plasmonic microscopy can image these fluid dynamical processes with a subnanometer sensitivity along the vertical direction.
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Affiliation(s)
- Shimon Rubin
- Department of Electrical and Computer Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92023 USA
| | - Brandon Hong
- Department of Electrical and Computer Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92023 USA
| | - Yeshaiahu Fainman
- Department of Electrical and Computer Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92023 USA
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6
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Ryu YK, Knoll AW. Oxidation and Thermal Scanning Probe Lithography for High-Resolution Nanopatterning and Nanodevices. ELECTRICAL ATOMIC FORCE MICROSCOPY FOR NANOELECTRONICS 2019. [DOI: 10.1007/978-3-030-15612-1_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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7
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Rawlings C, Ryu YK, Rüegg M, Lassaline N, Schwemmer C, Duerig U, Knoll AW, Durrani Z, Wang C, Liu D, Jones ME. Fast turnaround fabrication of silicon point-contact quantum-dot transistors using combined thermal scanning probe lithography and laser writing. NANOTECHNOLOGY 2018; 29:505302. [PMID: 30248025 DOI: 10.1088/1361-6528/aae3df] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The fabrication of high-performance solid-state silicon quantum-devices requires high resolution patterning with minimal substrate damage. We have fabricated room temperature (RT) single-electron transistors (SETs) based on point-contact tunnel junctions using a hybrid lithography tool capable of both high resolution thermal scanning probe lithography and high throughput direct laser writing. The best focal z-position and the offset of the tip- and the laser-writing positions were determined in situ with the scanning probe. We demonstrate <100 nm precision in the registration between the high resolution and high throughput lithographies. The SET devices were fabricated on degenerately doped n-type >1020/cm3 silicon on insulator chips using a CMOS compatible geometric oxidation process. The characteristics of the three devices investigated were dominated by the presence of Si nanocrystals or phosphorous atoms embedded within the SiO2, forming quantum dots (QDs). The small size and strong localisation of electrons on the QDs facilitated SET operation even at RT. Temperature measurements showed that in the range 300 K > T > ∼100 K, the current flow was thermally activated but at <100 K, it was dominated by tunnelling.
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Affiliation(s)
- Colin Rawlings
- IBM Research-Zurich, Saeumerstrasse 4, 8803 Rueschlikon, Switzerland
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8
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Liu L, Shi J, Li M, Yu P, Yang T, Li G. Fabrication of Sub-Micrometer-Sized MoS 2 Thin-Film Transistor by Phase Mode AFM Lithography. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1803273. [PMID: 30239118 DOI: 10.1002/smll.201803273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Indexed: 05/27/2023]
Abstract
The phase mode atomic force microscopy (AFM) lithography and monolayer lift-off process are combined to fabricate electronics based on 2D materials (2DMs), which remove the need for pre-fabricating markers and increase the accuracy of the overlay and alignment. The promising phase mode of AFM lithography eliminates the drawbacks of the conventional force mode such as the over-cut, under-cut, debris effect, and severe tip wear. The planar size of MoS2 thin-film transistors is shrunken down to sub-micrometer by the proposed method, and the fabricated devices demonstrate n-type characteristics. It offers a more flexible and easier way to fabricate prototypes of sub-micrometer-sized 2DMs based devices, and gives the opportunity to explore the size effect on the performance of 2DMs devices.
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Affiliation(s)
- Lianqing Liu
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Science, Shenyang, 110016, China
| | - Jialin Shi
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Science, Shenyang, 110016, China
| | - Meng Li
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Science, Shenyang, 110016, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Peng Yu
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Science, Shenyang, 110016, China
| | - Tie Yang
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Science, Shenyang, 110016, China
| | - Guangyong Li
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
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9
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Ni S, Isa L, Wolf H. Capillary assembly as a tool for the heterogeneous integration of micro- and nanoscale objects. SOFT MATTER 2018; 14:2978-2995. [PMID: 29611588 DOI: 10.1039/c7sm02496g] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
During the past decade, capillary assembly in topographical templates has evolved into an efficient method for the heterogeneous integration of micro- and nano-scale objects on a variety of surfaces. This assembly route has been applied to a large spectrum of materials of micrometer to nanometer dimensions, supplied in the form of aqueous colloidal suspensions. Using systems produced via bulk synthesis affords a huge flexibility in the choice of materials, holding promise for the realization of novel superior devices in the fields of optics, electronics and health, if they can be integrated into surface structures in a fast, simple, and reliable way. In this review, the working principles of capillary assembly and its fundamental process parameters are first presented and discussed. We then examine the latest developments in template design and tool optimization to perform capillary assembly in more robust and efficient ways. This is followed by a focus on the broad range of functional materials that have been realized using capillary assembly, from single components to large-scale heterogeneous multi-component assemblies. We then review current applications of capillary assembly, especially in optics, electronics, and in biomaterials. We conclude with a short summary and an outlook for future developments.
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Affiliation(s)
- Songbo Ni
- IBM Research - Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland.
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10
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Dehnert M, Magerle R. 3D depth profiling of the interaction between an AFM tip and fluid polymer solutions. NANOSCALE 2018. [PMID: 29532845 DOI: 10.1039/c8nr00299a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In the atomic force microscopy (AFM) investigation of soft polymers and liquids, the tip-sample interaction is dominated by long-range van der Waals forces, capillary forces and adhesion. Furthermore, the tip can indent several tens of nanometres into the surface, and it can pull off a polymer filament from the surface. Therefore, measuring the unperturbed shape of a polymeric fluid can be challenging. Here, we study the tip-sample interaction with polystyrene droplets swollen in chloroform vapour, where we can utilize the solvent vapour concentration to adjust the specimen's mechanical properties from a stiff solid to a fluid film. With the same AFM tip, we use two different AFM force spectroscopy methods to measure three-dimensional (3D) depth profiles of the tip-sample interaction: force-distance (FD) curves and amplitude-phase-distance (APD) curves. The 3D depth profiles reconstructed from FD and APD measurements provide detailed insight into the tip-sample interaction mechanism for a fluid polymer solution. The fluid's intrinsic relaxation time, which we measure with an AFM-based step-strain experiment, is essential for understanding the tip-sample interaction mechanism. Furthermore, measuring 3D depth profiles and using APD data to reconstruct the unperturbed surface comprise a versatile methodology for obtaining accurate dimensional measurements of fluid and gel-like objects on the nanometre scale.
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Affiliation(s)
- Martin Dehnert
- Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany.
| | - Robert Magerle
- Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany.
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11
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Ryu Cho YK, Rawlings CD, Wolf H, Spieser M, Bisig S, Reidt S, Sousa M, Khanal SR, Jacobs TDB, Knoll AW. Sub-10 Nanometer Feature Size in Silicon Using Thermal Scanning Probe Lithography. ACS NANO 2017; 11:11890-11897. [PMID: 29083870 PMCID: PMC5746844 DOI: 10.1021/acsnano.7b06307] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 10/30/2017] [Indexed: 05/20/2023]
Abstract
High-resolution lithography often involves thin resist layers which pose a challenge for pattern characterization. Direct evidence that the pattern was well-defined and can be used for device fabrication is provided if a successful pattern transfer is demonstrated. In the case of thermal scanning probe lithography (t-SPL), highest resolutions are achieved for shallow patterns. In this work, we study the transfer reliability and the achievable resolution as a function of applied temperature and force. Pattern transfer was reliable if a pattern depth of more than 3 nm was reached and the walls between the patterned lines were slightly elevated. Using this geometry as a benchmark, we studied the formation of 10-20 nm half-pitch dense lines as a function of the applied force and temperature. We found that the best pattern geometry is obtained at a heater temperature of ∼600 °C, which is below or close to the transition from mechanical indentation to thermal evaporation. At this temperature, there still is considerable plastic deformation of the resist, which leads to a reduction of the pattern depth at tight pitch and therefore limits the achievable resolution. By optimizing patterning conditions, we achieved 11 nm half-pitch dense lines in the HM8006 transfer layer and 14 nm half-pitch dense lines and L-lines in silicon. For the 14 nm half-pitch lines in silicon, we measured a line edge roughness of 2.6 nm (3σ) and a feature size of the patterned walls of 7 nm.
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Affiliation(s)
| | - Colin D. Rawlings
- IBM
Research Zurich, Säumerstrasse
4, 8803 Rüschlikon, Switzerland
- SwissLitho
AG, Technoparkstrasse
1, 8005 Zurich, Switzerland
| | - Heiko Wolf
- IBM
Research Zurich, Säumerstrasse
4, 8803 Rüschlikon, Switzerland
| | - Martin Spieser
- SwissLitho
AG, Technoparkstrasse
1, 8005 Zurich, Switzerland
| | - Samuel Bisig
- SwissLitho
AG, Technoparkstrasse
1, 8005 Zurich, Switzerland
| | - Steffen Reidt
- IBM
Research Zurich, Säumerstrasse
4, 8803 Rüschlikon, Switzerland
| | - Marilyne Sousa
- IBM
Research Zurich, Säumerstrasse
4, 8803 Rüschlikon, Switzerland
| | - Subarna R. Khanal
- University
of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | | | - Armin W. Knoll
- IBM
Research Zurich, Säumerstrasse
4, 8803 Rüschlikon, Switzerland
- E-mail:
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12
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Abstract
Force microscopy enables a variety of approaches to manipulate and/or modify surfaces. Few of those methods have evolved into advanced probe-based lithographies. Oxidation scanning probe lithography (o-SPL) is the only lithography that enables the direct and resist-less nanoscale patterning of a large variety of materials, from metals to semiconductors; from self-assembled monolayers to biomolecules. Oxidation SPL has also been applied to develop sophisticated electronic and nanomechanical devices such as quantum dots, quantum point contacts, nanowire transistors or mechanical resonators. Here, we review the principles, instrumentation aspects and some device applications of o-SPL. Our focus is to provide a balanced view of the method that introduces the key steps in its evolution, provides some detailed explanations on its fundamentals and presents current trends and applications. To illustrate the capabilities and potential of o-SPL as an alternative lithography we have favored the most recent and updated contributions in nanopatterning and device fabrication.
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13
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Bruzas I, Unser S, Yazdi S, Ringe E, Sagle L. Ultrasensitive Plasmonic Platform for Label-Free Detection of Membrane-Associated Species. Anal Chem 2016; 88:7968-74. [PMID: 27436204 DOI: 10.1021/acs.analchem.6b00801] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Lipid membranes and membrane proteins are important biosensing targets, motivating the development of label-free methods with improved sensitivity. Silica-coated metal nanoparticles allow these systems to be combined with supported lipid bilayers for sensing membrane proteins through localized surface plasmon resonance (LSPR). However, the small sensing volume of LSPR makes the thickness of the silica layer critical for performance. Here, we develop a simple, inexpensive, and rapid sol-gel method for preparing thin conformal, continuous silica films and demonstrate its applicability using gold nanodisk arrays with LSPRs in the near-infrared range. Silica layers as thin as ∼5 nm are observed using cross-sectional scanning transmission electron microscopy. The loss in sensitivity due to the thin silica coating was found to be only 16%, and the biosensing capabilities of the substrates were assessed through the binding of cholera toxin B to GM1 lipids. This sensor platform should prove useful in the rapid, multiplexed detection and screening of membrane-associated biological targets.
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Affiliation(s)
- Ian Bruzas
- Department of Chemistry, College of Arts and Sciences, University of Cincinnati , 301 West Clifton Court, Cincinnati, Ohio 45221-0172, United States
| | - Sarah Unser
- Department of Chemistry, College of Arts and Sciences, University of Cincinnati , 301 West Clifton Court, Cincinnati, Ohio 45221-0172, United States
| | - Sadegh Yazdi
- Department of Materials Science and NanoEngineering, Rice University , 6100 Main Street, MS-325, Houston, Texas 77005, United States
| | - Emilie Ringe
- Department of Materials Science and NanoEngineering, Rice University , 6100 Main Street, MS-325, Houston, Texas 77005, United States
| | - Laura Sagle
- Department of Chemistry, College of Arts and Sciences, University of Cincinnati , 301 West Clifton Court, Cincinnati, Ohio 45221-0172, United States
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Perrino AP, Ryu YK, Amo CA, Morales MP, Garcia R. Subsurface imaging of silicon nanowire circuits and iron oxide nanoparticles with sub-10 nm spatial resolution. NANOTECHNOLOGY 2016; 27:275703. [PMID: 27232523 DOI: 10.1088/0957-4484/27/27/275703] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Non-destructive subsurface characterization of nanoscale structures and devices is of significant interest in nanolithography and nanomanufacturing. In those areas, the accurate location of the buried structures and their nanomechanical properties are relevant for optimization of the nanofabrication process and the functionality of the system. Here we demonstrate the capabilities of bimodal and trimodal force microscopy for imaging silicon nanowire devices buried under an ultrathin polymer film. We resolve the morphology and periodicities of silicon nanowire pairs. We report a spatial resolution in the sub-10 nm range for nanostructures buried under a 70 nm thick polymer film. By using numerical simulations we explain the role of the excited modes in the subsurface imaging process. Independent of the bimodal or trimodal atomic force microscopy approach, the fundamental mode is the most suitable for tracking the topography while the higher modes modulate the interaction of the tip with the buried nanostructures and provide subsurface contrast.
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Affiliation(s)
- A P Perrino
- Instituto de Ciencia de Materiales de Madrid, CSIC c/Sor Juna Ines de la Cruz 3, 28049 Madrid, Spain
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15
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Thermal scanning probe lithography. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/b978-0-08-100354-1.00016-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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