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Bauer J, Crook C, Baldacchini T. A sinterless, low-temperature route to 3D print nanoscale optical-grade glass. Science 2023; 380:960-966. [PMID: 37262172 DOI: 10.1126/science.abq3037] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 04/12/2023] [Indexed: 06/03/2023]
Abstract
Three-dimensional (3D) printing of silica glass is dominated by techniques that rely on traditional particle sintering. At the nanoscale, this limits their adoption within microsystem technology, which prevents technological breakthroughs. We introduce the sinterless, two-photon polymerization 3D printing of free-form fused silica nanostructures from a polyhedral oligomeric silsesquioxane (POSS) resin. Contrary to particle-loaded sacrificial binders, our POSS resin itself constitutes a continuous silicon-oxygen molecular network that forms transparent fused silica at only 650°C. This temperature is 500°C lower than the sintering temperatures for fusing discrete silica particles to a continuum, which brings silica 3D printing below the melting points of essential microsystem materials. Simultaneously, we achieve a fourfold resolution enhancement, which enables visible light nanophotonics. By demonstrating excellent optical quality, mechanical resilience, ease of processing, and coverable size scale, our material sets a benchmark for micro- and nano-3D printing of inorganic solids.
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Affiliation(s)
- J Bauer
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Materials Science and Engineering Department, University of California, Irvine, CA 94550, USA
| | - C Crook
- Materials Science and Engineering Department, University of California, Irvine, CA 94550, USA
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Liaros N, Gutierrez Razo SA, Thum MD, Ogden HM, Zeppuhar AN, Wolf S, Baldacchini T, Kelley MJ, Petersen JS, Falvey DE, Mullin AS, Fourkas JT. Elucidating complex triplet-state dynamics in the model system isopropylthioxanthone. iScience 2022; 25:103600. [PMID: 35005547 PMCID: PMC8717599 DOI: 10.1016/j.isci.2021.103600] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/10/2021] [Accepted: 12/03/2021] [Indexed: 11/19/2022] Open
Abstract
We introduce techniques for probing the dynamics of triplet states. We employ these tools, along with conventional techniques, to develop a detailed understanding of a complex chemical system: a negative-tone, radical photoresist for multiphoton absorption polymerization in which isopropylthioxanthone (ITX) is the photoinitiator. This work reveals that the same color of light used for the 2-photon excitation of ITX, leading to population of the triplet manifold through intersystem crossing, also depletes this triplet population via linear absorption followed by reverse intersystem crossing (RISC). Using spectroscopic tools and kinetic modeling, we identify the reactive triplet state and a non-reactive reservoir triplet state. We present compelling evidence that the deactivation channel involves RISC from an excited triplet state to a highly vibrationally excited level of the electronic ground state. The work described here offers the enticing possibility of understanding, and ultimately controlling, the photochemistry and photophysics of a broad range of triplet processes.
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Affiliation(s)
- Nikolaos Liaros
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | | | - Matthew D. Thum
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Hannah M. Ogden
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Andrea N. Zeppuhar
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Steven Wolf
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | | | | | - John S. Petersen
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
- imec, Kapeldreef 75, 3001 Leuven, Belgium
| | - Daniel E. Falvey
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Amy S. Mullin
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - John T. Fourkas
- Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, USA
- Institute for Physical Science & Technology, University of Maryland, College Park, MD 20742, USA
- Maryland Quantum Materials Center, University of Maryland, College Park, MD 20742, USA
- Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
- Corresponding author
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Bauer J, Izard AG, Zhang Y, Baldacchini T, Valdevit L. Thermal post-curing as an efficient strategy to eliminate process parameter sensitivity in the mechanical properties of two-photon polymerized materials. Opt Express 2020; 28:20362-20371. [PMID: 32680097 DOI: 10.1364/oe.395986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
Two-photon polymerization direct laser writing (TPP-DLW) is one of the most versatile technologies to additively manufacture complex parts with nanoscale resolution. However, the wide range of mechanical properties that results from the chosen combination of multiple process parameters imposes an obstacle to its widespread use. Here we introduce a thermal post-curing route as an effective and simple method to increase the mechanical properties of acrylate-based TPP-DLW-derived parts by 20-250% and to largely eliminate the characteristic coupling of processing parameters, material properties and part functionality. We identify the underlying mechanism of the property enhancement as a self-initiated thermal curing reaction, which robustly facilitates the high property reproducibility that is essential for any application of TPP-DLW.
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Butkutė A, Čekanavičius L, Rimšelis G, Gailevičius D, Mizeikis V, Melninkaitis A, Baldacchini T, Jonušauskas L, Malinauskas M. Optical damage thresholds of microstructures made by laser three-dimensional nanolithography: publisher's note. Opt Lett 2020. [PMID: 32058522 DOI: 10.1364/ol.45.000013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
This publisher's note contains corrections to Opt. Lett.45, 13 (2020).OPLEDP0146-959210.1364/OL.45.000013.
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Butkutė A, Čekanavičius L, Rimšelis G, Gailevičius D, Mizeikis V, Melninkaitis A, Baldacchini T, Jonušauskas L, Malinauskas M. Optical damage thresholds of microstructures made by laser three-dimensional nanolithography: publisher's note. Opt Lett 2020; 45:980. [PMID: 32058522 DOI: 10.1364/ol.389912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Indexed: 06/10/2023]
Abstract
This publisher's note contains corrections to Opt. Lett.45, 13 (2020).OPLEDP0146-959210.1364/OL.45.000013.
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Jonušauskas L, Gailevičius D, Rekštytė S, Baldacchini T, Juodkazis S, Malinauskas M. Mesoscale laser 3D printing. Opt Express 2019; 27:15205-15221. [PMID: 31163720 DOI: 10.1364/oe.27.015205] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
3D meso scale structures that can reach up to centimeters in overall size but retain micro- or nano-features, proved to be promising in various science fields ranging from micro-mechanical metamaterials to photonics and bio-medical scaffolds. In this work, we present synchronization of the linear and galvanometric scanners for efficient femtosecond 3D optical printing of objects at the meso-scale (from sub-μm to sub-cm spanning five orders of magnitude). In such configuration, the linear stages provide stitch-free structuring at nearly limitless (up to tens-of-cm) working area, while galvo-scanners allow to achieve translation velocities in the range of mm/s-cm/s without sacrificing nano-scale positioning accuracy and preserving the undistorted shape of the final print. The principle behind this approach is demonstrated, proving its inherent advantages in comparison to separate use of only linear stages or scanners. The printing rate is calculated in terms of voxels/s, showcasing the capability to maintain an optimal feature size while increasing throughput. Full capabilities of this approach are demonstrated by fabricating structures that reach millimeters in size but still retain sub-μm features: scaffolds for cell growth, microlenses, and photonic crystals. All this is combined into a benchmark structure: a meso-butterfly. Provided results show that synchronization of two scan modes is crucial for the end goal of industrial-scale implementation of this technology and makes the laser printing well aligned with similar approaches in nanofabrication by electron and ion beams.
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Jiang L, Xiong W, Zhou Y, Liu Y, Huang X, Li D, Baldacchini T, Jiang L, Lu Y. Performance comparison of acrylic and thiol-acrylic resins in two-photon polymerization. Opt Express 2016; 24:13687-701. [PMID: 27410383 DOI: 10.1364/oe.24.013687] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Microfabrication by two-photon polymerization is investigated using resins based on thiol-ene chemistry. In particular, resins containing different amounts of a tetrafunctional acrylic monomer and a tetrafunctional thiol molecule are used to create complex microstructures. We observe the enhancement of several characteristics of two-photon polymerization when using thiol-acrylic resins. Specifically, microfabrication is carried out using higher writing velocities and it produces stronger polymeric microstructures. Furthermore, the amount of shrinkage typically observed in the production of three-dimensional microstructures is reduced also. By means of microspectrometry, we confirm that the thiol-acrylate mixture in TPP resins promote monomer conversion inducing a higher degree of cross-linked network formation.
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Jiang LJ, Zhou YS, Xiong W, Gao Y, Huang X, Jiang L, Baldacchini T, Silvain JF, Lu YF. Two-photon polymerization: investigation of chemical and mechanical properties of resins using Raman microspectroscopy. Opt Lett 2014; 39:3034-7. [PMID: 24978266 DOI: 10.1364/ol.39.003034] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this study, the degree of conversion (DC) of an acrylic-based resin (IP-L 780) in two-photon polymerization (TPP) is systematically investigated via Raman microspectroscopy. A quantitative relationship between TPP laser parameters and the DC of the resin is established. Nonlinear increase in DC with increased laser average power is observed. The resin DC is more sensitive to the laser average power than the laser writing speed. Nanoindentation was employed to correlate the results obtained from Raman microspectroscopy with the mechanical properties of microstructures fabricated by TPP. At constant writing speeds, microstructures fabricated with high laser average powers possess high hardness and high reduced Young's modulus (RYM), indicating high DCs. The results are in line with high DCs measured under the same TPP parameters in Raman microspectroscopy. Raman microspectroscopy is proved to be an effective, rapid, and nondestructive method characterizing microstructures fabrication by TPP.
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Baldacchini T, Snider S, Zadoyan R. Two-photon polymerization with variable repetition rate bursts of femtosecond laser pulses. Opt Express 2012; 20:29890-29899. [PMID: 23388815 DOI: 10.1364/oe.20.029890] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We describe fabrication of microstructures by two-photon polymerization using bursts of femtosecond laser pulses. With the aid of an acousto-optic modulator driven by a function generator, two-photon polymerization is performed at variable burst repetition rates. We investigate how the time between the bursts of laser pulses influences the ultimate dimensions of lines written in a photosensitive resin. We observe that when using the same laser fluence, polymer lines fabricated at different burst repetition rates have different dimensions. In particular, the widths of two-photon polymerized lines become smaller with decreasing burst repetition rates. Based on the thermal properties of the resin and experimental writing conditions, we attribute this effect to localized heat accumulation.
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Affiliation(s)
- Tommaso Baldacchini
- Technology and Applications Center, Newport Corporation, 1791 Deere Avenue, Irvine, California 92606, USA
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He XN, Allen J, Black PN, Baldacchini T, Huang X, Huang H, Jiang L, Lu YF. Coherent anti-Stokes Raman scattering and spontaneous Raman spectroscopy and microscopy of microalgae with nitrogen depletion. Biomed Opt Express 2012; 3:2896-906. [PMID: 23162727 PMCID: PMC3493223 DOI: 10.1364/boe.3.002896] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/13/2012] [Accepted: 10/15/2012] [Indexed: 05/04/2023]
Abstract
Microalgae are extensively researched as potential feedstocks for biofuel production. Energy-rich compounds in microalgae, such as lipids, require efficient characterization techniques to investigate the metabolic pathways and the environmental factors influencing their accumulation. The model green alga Coccomyxa accumulates significant amounts of triacylglycerols (TAGs) under nitrogen depletion (N-depletion). To monitor the growth of TAGs (lipid) in microalgal cells, a study of microalgal cells (Coccomyxa sp. C169) using both spontaneous Raman and coherent anti-Stokes Raman scattering (CARS) spectroscopy and microscopy were carried out. Spontaneous Raman spectroscopy was conducted to analyze the components in the algal cells, while CARS was carried out to monitor the distribution of lipid droplets in the cells. Raman signals of carotenoid are greater in control microalgae compared to N-depleted cells. Raman signals of lipid droplets appear after N-depletion and its distribution can be clearly observed in the CARS microscopy. Both spontaneous Raman spectroscopy and CARS microscopy were found to be suitable analysis tools for microalgae.
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Affiliation(s)
- X. N. He
- Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0511, USA
| | - J. Allen
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588-0664, USA
| | - P. N. Black
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588-0664, USA
| | - T. Baldacchini
- Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0511, USA
- Technology and Applications Center, Newport Corporation, Irvine, CA 92606, USA
| | - X. Huang
- Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0511, USA
| | - H. Huang
- Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0511, USA
| | - L. Jiang
- Department of Mechanical and Automation Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Y. F. Lu
- Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0511, USA
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Baldacchini T, Zadoyan R. In situ and real time monitoring of two-photon polymerization using broadband coherent anti-Stokes Raman scattering microscopy. Opt Express 2010; 18:19219-31. [PMID: 20940818 DOI: 10.1364/oe.18.019219] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We demonstrate in situ and real time characterization of two-photon polymerization (TPP) by means of broadband coherent anti-Stokes Raman scattering (CARS) microscopy. The same experimental setup based on one femtosecond oscillator is used to perform both TPP and broadband CARS microscopy. We performed in situ imaging with chemical specificity of three-dimensional microstructures fabricated by TPP, and successfully followed the writing process in real time. Broadband CARS microscopy allowed discerning between polymerized and unpolymerized material. Imaging with good vibrational contrast is achieved without causing any damage to the microstructures or undesired polymerization within the sample.
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Affiliation(s)
- Tommaso Baldacchini
- Technology and Applications Center, Newport Corporation, 1791 Deere Avenue, Irvine, CA 92606, USA
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Baldacchini T, Zimmerley M, Kuo CH, Potma EO, Zadoyan R. Characterization of microstructures fabricated by two-photon polymerization using coherent anti-stokes Raman scattering microscopy. J Phys Chem B 2009; 113:12663-8. [PMID: 19715350 DOI: 10.1021/jp9058998] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We demonstrate the possibility to image microstructures fabricated by two-photon polymerization (TPP) using coherent anti-Stokes Raman scattering (CARS) microscopy. The imaging contrast based on chemical selectivity attained by CARS microscopy is used to gather qualitative information on TPP. Upon the basis of detailed knowledge of the characteristic signatures of the photoresist Raman spectrum, quantitative relationships between laser writing conditions and polymer cross-linking are demonstrated. The increase in degree of polymer conversion as a function of laser average power follows a sigmoidal profile which is interpreted in terms of a simple model based on the polymerization mechanism of the photoresist.
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Affiliation(s)
- Tommaso Baldacchini
- Technology and Applications Center, Newport Corporation, Irvine, California 92606, USA.
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Balu M, Baldacchini T, Carter J, Krasieva TB, Zadoyan R, Tromberg BJ. Effect of excitation wavelength on penetration depth in nonlinear optical microscopy of turbid media. J Biomed Opt 2009; 14:010508. [PMID: 19256688 PMCID: PMC2868513 DOI: 10.1117/1.3081544] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We present a comparative study of two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) imaging in turbid media at 800- and 1300-nm excitation. The depth-dependent decay of TPEF and SHG signals in turbid tissue phantoms is used to estimate the impact of light scattering on excitation intensity at each wavelength. A 50 to 80% increase in scattering length is observed using 1300-nm excitation, while peak TPEF emission intensity is obtained 10 to 20 microm beneath the surface for both sources. The increased penetration depth at 1300 nm is confirmed by TPEF and SHG microscopy of tissue phantoms composed of gelatin/microspheres and 3-D organotypic collagen-fibroblast cultures, respectively. Our results establish the feasibility of 1.3-microm excitation in nonlinear optical microscopy.
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Affiliation(s)
- Mihaela Balu
- University of California, Irvine, Beckman Laser Institute Laser Microbeam and Medical Program, Irvine, CA 92617
| | - Tommaso Baldacchini
- Newport Corporation, Technology and Applications Center, Irvine, California 92606
| | - John Carter
- Newport Corporation, Technology and Applications Center, Irvine, California 92606
| | - Tatiana B. Krasieva
- University of California, Irvine, Beckman Laser Institute Laser Microbeam and Medical Program, Irvine, CA 92617
| | - Ruben Zadoyan
- Newport Corporation, Technology and Applications Center, Irvine, California 92606
| | - Bruce J. Tromberg
- University of California, Irvine, Beckman Laser Institute Laser Microbeam and Medical Program, Irvine, CA 92617
- Tel: 949-824-8367. Fax: 949-824-6969.
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Mendonca CR, Cerami LR, Shih T, Tilghman RW, Baldacchini T, Mazur E. Femtosecond laser waveguide micromachining of PMMA films with azoaromatic chromophores. Opt Express 2008; 16:200-206. [PMID: 18521148 DOI: 10.1364/oe.16.000200] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report on the femtosecond-laser micromachining of poly(methyl methacrylate) (PMMA) films doped with nonlinear azoaromatic chromophores: Disperse Red 1, Disperse Red 13 and Disperse Orange 3. We study the conditions for controlling chromophore degradation during the micromachining of PMMA doped with each chromophore. Furthermore, we successfully used fs-micromachining to fabricate optical waveguides within a bulk sample of PMMA doped with these azochromophores.
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Affiliation(s)
- C R Mendonca
- Department of Physics and Harvard School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138, USA
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LaFratta C, Fourkas J, Baldacchini T, Farrer R. Cover Picture: Multiphoton Fabrication (Angew. Chem. Int. Ed. 33/2007). Angew Chem Int Ed Engl 2007. [DOI: 10.1002/anie.200790161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
Chemical and physical processes driven by multiphoton absorption make possible the fabrication of complex, 3D structures with feature sizes as small as 100 nm. Since its inception less than a decade ago, the field of multiphoton fabrication has progressed rapidly, and multiphoton techniques are now being used to create functional microdevices. In this Review we discuss the techniques and materials used for multiphoton fabrication, the applications that have been demonstrated, as well as those being pursued. We also consider the outlook for this field, both in the laboratory and in industrial settings.
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Affiliation(s)
- Christopher N LaFratta
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
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Baldacchini T, Carey JE, Zhou M, Mazur E. Superhydrophobic surfaces prepared by microstructuring of silicon using a femtosecond laser. Langmuir 2006; 22:4917-9. [PMID: 16700574 DOI: 10.1021/la053374k] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We present a simple method for fabricating superhydrophobic silicon surfaces. The method consists of irradiating silicon wafers with femtosecond laser pulses and then coating the surfaces with a layer of fluoroalkylsilane molecules. The laser irradiation creates a surface morphology that exhibits structure on the micro- and nanoscale. By varying the laser fluence, we can tune the surface morphology and the wetting properties. We measured the static and dynamic contact angles for water and hexadecane on these surfaces. For water, the microstructured silicon surfaces yield contact angles higher than 160 degrees and negligible hysteresis. For hexadecane, the microstructuring leads to a transition from nonwetting to wetting.
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Affiliation(s)
- Tommaso Baldacchini
- Division of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, Massachusetts 02138, USA
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Baldacchini T, Pons AC, Pons J, Lafratta C, Fourkas J, Sun Y, Naughton M. Multiphoton laser direct writing of two-dimensional silver structures. Opt Express 2005; 13:1275-1280. [PMID: 19495000 DOI: 10.1364/opex.13.001275] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report a novel and efficient method for the laser direct writing of two-dimensional silver structures. Multiphoton absorption of a small fraction of the output of a Ti:sapphire oscillator is sufficient to photoreduce silver nitrate in a thin film of polyvinylpyrrolidone that has been spin-coated on a substrate. The polymer can then be washed away, leaving a pattern consisting of highly interconnected silver nanoparticles. We report the characterization of the silver patterns using scanning electron and atomic force microscopies, and demonstrate the application of this technique in the creation of diffraction gratings.
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LaFratta CN, Baldacchini T, Farrer RA, Fourkas JT, Teich MC, Saleh BEA, Naughton MJ. Replication of Two-Photon-Polymerized Structures with Extremely High Aspect Ratios and Large Overhangs. J Phys Chem B 2004. [DOI: 10.1021/jp048525r] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Baldacchini T, Monacelli F. Steric effect on the axial substitution of bis(dimethyl sulphoxide)phthalocyaninatoiron(II) by substituted imidazoles. Inorganica Chim Acta 1999. [DOI: 10.1016/s0020-1693(99)00381-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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