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Two-step absorption instead of two-photon absorption in 3D nanoprinting

Nature Photonics volume 15, pages 932–938 (2021)Cite this article

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Abstract

The quadratic optical nonlinearity arising from two-photon absorption provides the crucial spatial concentration of optical excitation in three-dimensional (3D) laser nanoprinting, with widespread applications in technical and life sciences. Femtosecond lasers allow for obtaining efficient two-photon absorption but are accompanied by a number of issues, including higher-order processes, cost, reliability and size. Here we introduce two-step absorption replacing two-photon absorption as the primary optical excitation process. Under suitable conditions, two-step absorption shows the same quadratic optical nonlinearity as two-photon absorption. We present a photoresist system based on a photoinitiator supporting two-step absorption, a scavenger and a well-established triacrylate. We show that this system allows for printing state-of-the-art 3D nanostructures and beyond. In these experiments, we use ~100 μW optical power from an inexpensive, compact continuous-wave semiconductor laser diode emitting at 405 nm wavelength. Our work opens the door to drastic miniaturization and cost reduction of 3D laser nanoprinters.

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Fig. 1: 3D laser nanoprinting using two-photon absorption or two-step absorption.
Fig. 2: Simplified energy-level model and rate-equation calculations for a two-step-absorption photoinitiator.
Fig. 3: Benzil as a two-step-absorption photoinitiator.
Fig. 4: Laser, laser focus and effective nonlinearity of the photoresist.
Fig. 5: Two-step-absorption printing resolution in two and three dimensions.
Fig. 6: Gallery of oblique-view electron micrographs of further 3D-printed nanostructures.

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Data availability

The data underlying the plots within this paper, Supplementary Information and related 3D printing files are published on the open-access data repository of the Karlsruhe Institute of Technology (https://doi.org/10.5445/IR/1000137134).

Code availability

The code for the computations shown in Fig. 2 is published on the open-access data repository of the Karlsruhe Institute of Technology (https://doi.org/10.5445/IR/1000137134).

References

  1. Göppert-Mayer, M. Über Elementarakte mit zwei Quantensprüngen. Ann. Phys. 401, 273–294 (1931).

    Article  MATH  Google Scholar 

  2. Scully, M. O. & Zubairy, M. S. Quantum Optics (Cambridge Univ. Press, 1997).

  3. Denk, W., Strickler, J. H. & Webb, W. W. Two-photon laser scanning fluorescence microscopy. Science 248, 73–76 (1990).

    Article  ADS  Google Scholar 

  4. Denk, W., Piston, D. W. & Webb, W. W. Multi-photon molecular excitation in laser-scanning microscopy. in Handbook Of Biological Confocal Microscopy (ed. Pawley, J. B.) 535–549 (Springer, 2006).

  5. Wu, E.-S., Strickler, J. H., Harrell, W. R. & Webb, W. W. Two-photon lithography for microelectronic application. In Proc. SPIE 1674, Optical/Laser Microlithography V 776–782 (International Society for Optics and Photonics, 1992).

  6. Maruo, S., Nakamura, O. & Kawata, S. Three-dimensional microfabrication with two-photon-absorbed photopolymerization. Opt. Lett. 22, 132–134 (1997).

    Article  ADS  Google Scholar 

  7. Baldacchini, T. (ed.) Three-Dimensional Microfabrication Using Two-Photon Polymerization 2nd edn (Elsevier, 2019).

  8. Farsari, M. & Chichkov, B. N. Two-photon fabrication. Nat. Photon. 3, 450–452 (2009).

    Article  ADS  Google Scholar 

  9. Gissibl, T., Thiele, S., Herkommer, A. & Giessen, H. Two-photon direct laser writing of ultracompact multi-lens objectives. Nat. Photon. 10, 554–560 (2016).

    Article  ADS  Google Scholar 

  10. Dietrich, P.-I. et al. In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration. Nat. Photon. 12, 241–247 (2018).

    Article  ADS  Google Scholar 

  11. Wolff, M. A. et al. Broadband waveguide-integrated superconducting single-photon detectors with high system detection efficiency. Appl. Phys. Lett. 118, 154004 (2021).

    Article  ADS  Google Scholar 

  12. Hahn, V. et al. Rapid assembly of small materials building blocks (voxels) into large functional 3D metamaterials. Adv. Funct. Mater. 30, 1907795 (2020).

    Article  Google Scholar 

  13. Skliutas, E. et al. Polymerization mechanisms initiated by spatio-temporally confined light. Nanophotonics 10, 1211–1242 (2021).

    Article  Google Scholar 

  14. Kiefer, P. et al. Sensitive photoresists for rapid multiphoton 3D laser micro- and nanoprinting. Adv. Opt. Mater. 8, 2000895 (2020).

    Article  Google Scholar 

  15. Schafer, K. J. et al. Two-photon absorption cross-sections of common photoinitiators. J. Photochem. Photobiol. Chem. 162, 497–502 (2004).

    Article  Google Scholar 

  16. Pawlicki, M., Collins, H. A., Denning, R. G. & Anderson, H. L. Two-photon absorption and the design of two-photon dyes. Angew. Chem. Int. Ed. 48, 3244–3266 (2009).

    Article  Google Scholar 

  17. Mueller, J. B., Fischer, J., Mange, Y. J., Nann, T. & Wegener, M. In-situ local temperature measurement during three-dimensional direct laser writing. Appl. Phys. Lett. 103, 123107 (2013).

    Article  ADS  Google Scholar 

  18. Fischer, J. et al. Three-dimensional multi-photon direct laser writing with variable repetition rate. Opt. Express 21, 26244–26260 (2013).

    Article  ADS  Google Scholar 

  19. Tumbleston, J. R. et al. Continuous liquid interface production of 3D objects. Science 347, 1349–1352 (2015).

    Article  ADS  Google Scholar 

  20. Dexter, D. L. Possibility of luminescent quantum yields greater than unity. Phys. Rev. 108, 630–633 (1957).

    Article  ADS  Google Scholar 

  21. Wegh, R. T., Donker, H., Oskam, K. D. & Meijerink, A. Visible quantum cutting in LiGdF4:Eu3+ through downconversion. Science 283, 663–666 (1999).

    Article  ADS  Google Scholar 

  22. Burnham, D. C. & Weinberg, D. L. Observation of simultaneity in parametric production of optical photon pairs. Phys. Rev. Lett. 25, 84–87 (1970).

    Article  ADS  Google Scholar 

  23. Fischer, J. & Wegener, M. Three-dimensional direct laser writing inspired by stimulated-emission-depletion microscopy. Opt. Mater. Express 1, 614–624 (2011).

    Article  ADS  Google Scholar 

  24. Turro, N. J. Modern Molecular Photochemistry (University Science Books, 1991).

  25. Flamigni, L., Barigelletti, F., Dellonte, S. & Orlandi, G. Photophysical properties of benzil in solution: triplet state deactivation pathways. J. Photochem. 21, 237–244 (1983).

    Article  Google Scholar 

  26. Lamola, A. A. & Hammond, G. S. Mechanisms of photochemical reactions in solution. XXXIII. Intersystem crossing efficiencies. J. Chem. Phys. 43, 2129–2135 (1965).

    Article  ADS  Google Scholar 

  27. Fang, T.-S., Brown, R. E., Kwan, C. L. & Singer, L. A. Photophysical studies on benzil. Time resolution of the prompt and delayed emissions and a photokinetic study indicating deactivation of the triplet by reversible exciplex formation. J. Phys. Chem. 82, 2489–2496 (1978).

    Article  Google Scholar 

  28. Bückmann, T. et al. Tailored 3D mechanical metamaterials made by dip-in direct-laser-writing optical lithography. Adv. Mater. 24, 2710–2714 (2012).

    Article  Google Scholar 

  29. Scaiano, J. C., Johnston, L. J., McGimpsey, W. G. & Weir, D. Photochemistry of organic reaction intermediates: novel reaction paths induced by two-photon laser excitation. Acc. Chem. Res. 21, 22–29 (1988).

    Article  Google Scholar 

  30. Cáceres, T., Encinas, M. V. & Lissi, E. A. Photocleavage of benzil. J. Photochem. 27, 109–114 (1984).

    Article  Google Scholar 

  31. Grubbs, R. B. Nitroxide-mediated radical polymerization: limitations and versatility. Polym. Rev. 51, 104–137 (2011).

    Article  Google Scholar 

  32. Johnston, L. J., Tencer, M. & Scaiano, J. C. Evidence for hydrogen transfer in the photochemistry of 2,2,6,6-tetramethylpiperidine N-oxyl. J. Org. Chem. 51, 2806–2808 (1986).

    Article  Google Scholar 

  33. Tatikolov, A. S., Levin, P. P., Kokrashvili, T. A. & Kuz’min, V. A. Quenching of the triplet states of carbonyl compounds by nitroxyl radicals. Russ. Chem. Bull. 32, 465–468 (1983).

  34. Bunbury, D. L. & Chuang, T. T. Photolysis of benzil in 2-propanol and in cumene. Can. J. Chem. 47, 2045–2055 (1969).

    Article  Google Scholar 

  35. Arnoux, C. et al. Polymerization photoinitiators with near-resonance enhanced two-photon absorption cross-section: toward high-resolution photoresist with improved sensitivity. Macromolecules 53, 9264–9278 (2020).

    Article  ADS  Google Scholar 

  36. Malinauskas, M. et al. Ultrafast laser processing of materials: from science to industry. Light: Sci. Appl. 5, e16133 (2016).

    Article  Google Scholar 

  37. Ikuta, K., Maruo, S. & Kojima, S. New micro stereo lithography for freely movable 3D micro structure-super IH process with submicron resolution. In Proc. MEMS 98. IEEE. Eleventh Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems (Cat. No. 98CH36176) 290–295 (IEEE, 1998).

  38. Thiel, M., Fischer, J., von Freymann, G. & Wegener, M. Direct laser writing of three-dimensional submicron structures using a continuous-wave laser at 532 nm. Appl. Phys. Lett. 97, 221102 (2010).

    Article  ADS  Google Scholar 

  39. Do, M. T. et al. Submicrometer 3D structures fabrication enabled by one-photon absorption direct laser writing. Opt. Express 21, 20964–20973 (2013).

    Article  ADS  Google Scholar 

  40. Delrot, P., Loterie, D., Psaltis, D. & Moser, C. Single-photon three-dimensional microfabrication through a multimode optical fiber. Opt. Express 26, 1766–1778 (2018).

    Article  ADS  Google Scholar 

  41. Mueller, P., Thiel, M. & Wegener, M. 3D direct laser writing using a 405 nm diode laser. Opt. Lett. 39, 6847–6850 (2014).

    Article  ADS  Google Scholar 

  42. Shusteff, M. et al. One-step volumetric additive manufacturing of complex polymer structures. Sci. Adv. 3, eaao5496 (2017).

    Article  Google Scholar 

  43. Kelly, B. E. et al. Volumetric additive manufacturing via tomographic reconstruction. Science 363, 1075–1079 (2019).

    Article  Google Scholar 

  44. Loterie, D., Delrot, P. & Moser, C. High-resolution tomographic volumetric additive manufacturing. Nat. Commun. 11, 852 (2020).

    Article  ADS  Google Scholar 

  45. Regehly, M. et al. Xolography for linear volumetric 3D printing. Nature 588, 620–624 (2020).

    Article  ADS  Google Scholar 

  46. Schumann, M. F. et al. Cloaked contact grids on solar cells by coordinate transformations: designs and prototypes. Optica 2, 850–853 (2015).

    Article  ADS  Google Scholar 

  47. Urbancová, P. et al. IP-Dip-based woodpile structures for VIS and NIR spectral range: complex PBG analysis. Opt. Mater. Express 9, 4307–4317 (2019).

    Article  ADS  Google Scholar 

  48. Frenzel, T., Kadic, M. & Wegener, M. Three-dimensional mechanical metamaterials with a twist. Science 358, 1072–1074 (2017).

    Article  ADS  Google Scholar 

  49. #3DBenchy. https://www.3dbenchy.com/

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Acknowledgements

We acknowledge fruitful discussions with C. Barner-Kowollik (Queensland Institute of Technology), F. Mayer (Karlsruhe Institute of Technology (KIT)), P. Müller (previously at KIT) and T. Schlöder (KIT). V.H. is presently funded by the Max Planck School of Photonics. This research has additionally been funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy via the Excellence Cluster ‘3D Matter Made to Order’ (EXC-2082/1-390761711), which has also been supported by the Carl Zeiss Foundation through the ‘Carl Zeiss Foundation-Focus@HEiKA’, by the State of Baden-Württemberg, and by KIT. We further acknowledge support by the Helmholtz program ‘Materials Systems Engineering (MSE)’, and by the Karlsruhe School of Optics & Photonics (KSOP) and by the Ministry of Science, Research and the Arts of Baden-Württemberg as part of the sustainability financing of the projects of the Excellence Initiative II. R.R.S. acknowledges funding from the Federal Ministry for Education and Research (BMBF) under grant no. 13N14476.

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Authors and Affiliations

  1. Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

    Vincent Hahn, Tobias Messer & Martin Wegener

  2. Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

    Vincent Hahn, N. Maximilian Bojanowski, Eva Blasco & Martin Wegener

  3. BioQuant, Universitätsklinikum, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany

    Ernest Ronald Curticean & Rasmus R. Schröder

  4. Centre for Advanced Materials (CAM), Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany

    Irene Wacker, Rasmus R. Schröder & Eva Blasco

  5. Institute of Organic Chemistry, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany

    Eva Blasco

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  1. Vincent Hahn
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Contributions

V.H. and M.W. had the idea to use two-step absorption instead of two-photon absorption. V.H. screened possible photoinitiator candidates suitable for two-step absorption. V.H., T.M. and N.M.B. performed all the experiments and the corresponding analysis. E.R.C. and I.W. performed the sample preparation, ultramicrotomy and electron microscopy of the cross sections. R.R.S. prepared the 3D reconstruction of the woodpile structures. M.W. and E.B. supervised the project. M.W. drafted the first version of the paper. All the authors contributed to the interpretation of the results and writing of the manuscript.

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Correspondence to Vincent Hahn.

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Competing interests

V.H., T.M. and M.W. are inventors on a patent application on two-step absorption. The authors declare no other competing interests.

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Peer review information Nature Photonics thanks Paul Braun and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–9, Table 1, methods and references.

Supplementary Video 1

Three-dimensional volume rendering of a woodpile structure with a = 300 nm.

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Hahn, V., Messer, T., Bojanowski, N.M. et al. Two-step absorption instead of two-photon absorption in 3D nanoprinting. Nat. Photon. 15, 932–938 (2021). https://doi.org/10.1038/s41566-021-00906-8

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