Three-dimensional printing of transparent fused silica glass

Journal name:
Nature
Volume:
544,
Pages:
337–339
Date published:
DOI:
doi:10.1038/nature22061
Received
Accepted
Published online

Glass is one of the most important high-performance materials used for scientific research, in industry and in society, mainly owing to its unmatched optical transparency, outstanding mechanical, chemical and thermal resistance as well as its thermal and electrical insulating properties1, 2, 3. However, glasses and especially high-purity glasses such as fused silica glass are notoriously difficult to shape, requiring high-temperature melting and casting processes for macroscopic objects or hazardous chemicals for microscopic features3, 4. These drawbacks have made glasses inaccessible to modern manufacturing technologies such as three-dimensional printing (3D printing). Using a casting nanocomposite5, here we create transparent fused silica glass components using stereolithography 3D printers at resolutions of a few tens of micrometres. The process uses a photocurable silica nanocomposite that is 3D printed and converted to high-quality fused silica glass via heat treatment. The printed fused silica glass is non-porous, with the optical transparency of commercial fused silica glass, and has a smooth surface with a roughness of a few nanometres. By doping with metal salts, coloured glasses can be created. This work widens the choice of materials for 3D printing, enabling the creation of arbitrary macro- and microstructures in fused silica glass for many applications in both industry and academia.

At a glance

Figures

  1. 3D printing of fused silica glass.
    Figure 1: 3D printing of fused silica glass.

    a, Ultraviolet-curable monomer mixed with amorphous silica nanopowder is structured in a stereolithography system. The resulting polymerized composite is turned into fused silica glass through thermal debinding and sintering (scale bar, 7 mm). b, c, Examples of printed and sintered glass structures: Karlsruhe Institute of Technology logo (b; scale bar, 5 mm) and pretzel (c; scale bar, 5 mm). d, Demonstration of the high thermal resistance of printed fused silica glass (scale bar, 1 cm). The flame had a temperature of about 800 °C.

  2. Characterization of sintered glass and high resolution nanocomposite.
    Figure 2: Characterization of sintered glass and high resolution nanocomposite.

    a, b, X-ray photoelectron spectroscopy (a) and Raman spectrum (b) of printed and sintered glass compared to commercial fused silica glass. c, Left, ultraviolet–visible transmission of the index-matched nanocomposite for microstereolithography and the non-index-matched casting slurry5. At 365 nm (i-line) the transmission of the microstereolithography nanocomposite is increased by about 62%. The microstereolithography nanocomposite is highly transparent (about 66% transmission) while the casting slurry is strongly absorbing (about 4% transmission). Right, the casting and the microstereolithography nanocomposites.

  3. Microstructuring of fused silica glass.
    Figure 3: Microstructuring of fused silica glass.

    a, Microstereolithography of a hollow castle gate (scale bar, 270 μm). b, Microlithography of an exemplary microfluidic chip (inset scale bar, 200 μm). c, Micro-optical diffractive structure creating the optical projection pattern shown at the bottom (illuminated with a green laser pointer; scale bar, 100 μm). d, Microlenses fabricated using greyscale lithography (inset scale bar, 100 μm).

  4. Surface and optical characterization of sintered glass.
    Figure 4: Surface and optical characterization of sintered glass.

    a, The printed glass part shows the steps and side wall undulations from the layer-by-layer microstereolithography process. The part was printed with a 20-μm layer thickness (scale bar, 80 μm). b, Atomic force microscope measurement on a microfluidic channel in fused silica glass, showing very low surface roughness of the top surfaces of about 2 nm (scale bar, 260 μm); z is the measured height of the sample. c, Ultraviolet–visible transmission of printed and sintered glass compared to commercial fused silica. The transmission spectra are almost identical. Doping of sintered glass with metal salts leads to coloured binary fused silica glasses (shown on the right).

  5. Characterization of the nanocomposite processing.
    Extended Data Fig. 1: Characterization of the nanocomposite processing.

    a, Thermal gravimetric analysis of the cured nanocomposite used for stereolithography. The sample had a solid loading of 37.5 vol% SiO2. b, Corresponding heating programme for thermal debinding (I) and sintering (II) used for the composite shaped using stereolithography. c, Stereolithography cure depth (depth of a voxel upon exposure, corresponding to the penetration of the polymerization front during exposure) versus the laser power. The nanocomposites are highly stable and can be used for weeks with the same polymerization parameters.

  6. Material and surface characterization of sintered glass.
    Extended Data Fig. 2: Material and surface characterization of sintered glass.

    a, X-ray photoelectron spectroscopy narrow scans of elemental lines of printed and sintered glass compared to commercial fused silica glass. All spectra show virtually no difference between sintered fused silica glass and commercial fused silica glass. b, X-ray diffraction measurement shows that no devitrification occurs during the sintering process. Devitrification would present in the form of narrow peaks and spikes in the spectrum. c, Fourier transform infrared (FTIR) measurements of sintered glass compared to commercial fused silica glass.

Videos

  1. Three-dimensional printing of glass
    Video 1: Three-dimensional printing of glass
    The video gives a short introduction into the printing process of the nanocomposite, the thermal debinding and the sintering process.

References

  1. Hench, L. L., Day, D. E., Höland, W. & Rheinberger, V. M. Glass and medicine. Int. J. Appl. Glass Sci. 1, 104117 (2010)
  2. Ikushima, A., Fujiwara, T. & Saito, K. Silica glass: a material for photonics. J. Appl. Phys. 88, 12011213 (2000)
  3. Bansal, N. P. & Doremus, R. H. Handbook of Glass Properties 680 (Elsevier, 2013)
  4. Hülsenberg, D., Harnisch, A. & Bismarck, A. Microstructuring of Glasses 1st edn, Vol. 87, 323 (Springer, 2005)
  5. Kotz, F. et al. Liquid glass: a facile soft replication method for structuring glass. Adv. Mater. 28, 46464650 (2016)
  6. Klein, J. et al. Additive manufacturing of optically transparent glass. 3D Print. Additive Manuf. 2, 92105 (2015)
  7. Luo, J. et al. in Proc. Conf. SPIE LASE 97380Y–97380Y–9, http://dx.doi.org/10.1117/12.2218137 (International Society for Optics and Photonics, 2016)
  8. Luo, J., Pan, H. & Kinzel, E. C. Additive manufacturing of glass. J. Manuf. Sci. Eng. 136, 061024 (2014)
  9. Klein, S., Simske S., Parraman C., Walters P., Huson D. & Hoskins S. 3D Printing of Transparent Glass Technical Report HPL-2012-198, http://www.hpl.hp.com/techreports/2012/HPL-2012-198.pdf (Hewlett Packard Labs, 2012)
  10. Marchelli, G., Prabhakar, R., Storti, D. & Ganter, M. The guide to glass 3D printing: developments, methods, diagnostics and results. Rapid Prototyping J. 17, 187194 (2011)
  11. Fateri, M. & Gebhardt, A. Selective laser melting of soda-lime glass powder. Int. J. Appl. Ceram. Technol. 12, 5361 (2015)
  12. Klocke, F., McClung, A. & Ader, C. in Proc. Solid Freeform Fabrication Symp. 214–219, https://sffsymposium.engr.utexas.edu/Manuscripts/2004/2004-21-Klocke.pdf (2004)
  13. Shepherd, R. F. et al. Stop-flow lithography of colloidal, glass, and silicon microcomponents. Adv. Mater. 20, 47344739 (2008)
  14. Lin, J. et al. On-chip three-dimensional high-Q microcavities fabricated by femtosecond laser direct writing. Opt. Express 20, 1021210217 (2012)
  15. Raghavan, S. R., Walls, H. & Khan, S. A. Rheology of silica dispersions in organic liquids: new evidence for solvation forces dictated by hydrogen bonding. Langmuir 16, 79207930 (2000)
  16. Sun, C. & Zhang, X. The influences of the material properties on ceramic micro-stereolithography. Sens. Actuators A 101, 364370 (2002)
  17. Souder, W. H. & Hidnert, P. Measurements on the Thermal Expansion of Fused Silica 3 (Government Printing Office, 1926)
  18. Waldbaur, A., Carneiro, B., Hettich, P., Wilhelm, E. & Rapp, B. Computer-aided microfluidics (CAMF): from digital 3D-CAD models to physical structures within a day. Microfluid. Nanofluid. 15, 625635 (2013)
  19. Clasen, R. Preparation of coloured silica glasses made by sintering of particulate gels. Glastechnische Berichte 66, 299304 (1993)
  20. Schultz, P. C. Optical absorption of the transition elements in vitreous silica. J. Am. Ceram. Soc. 57, 309313 (1974)
  21. Kozuka, H. & Sakka, S. Preparation of gold colloid-dispersed silica-coating films by the sol-gel method. Chem. Mater. 5, 222228 (1993)
  22. Seah, M., Gilmore, I. & Beamson, G. XPS: binding energy calibration of electron spectrometers 5—re-evaluation of the reference energies. Surf. Interf. Anal. 26, 642649 (1998)
  23. Moulder, J. F., Stickle, W. F., Sobol, P. E & Bomben, K. D. Handbook of X-ray Photoelectron Spectroscopy: a Reference Book of Standard Spectra for Identification and Interpretation of XPS Data 238 (Physical Electronics Eden Prairie, 1995)

Download references

Author information

Affiliations

  1. Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany

    • Frederik Kotz,
    • Karl Arnold,
    • Nico Keller,
    • Kai Sachsenheimer,
    • Tobias M. Nargang,
    • Christiane Richter,
    • Dorothea Helmer &
    • Bastian E. Rapp
  2. Institute for Applied Materials (IAM), KIT, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany

    • Werner Bauer
  3. Institute for Nuclear Waste Disposal (INE), KIT, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany

    • Dieter Schild

Contributions

F.K. and B.E.R. conceived the idea. F.K. designed the experiments, synthesized the material and performed the stereolithography processes. K.A. performed the microlithography process. W.B. performed X-ray diffraction and thermal gravimetric analysis measurements. C.R. performed white-light interferometry measurements. N.K., T.M.N. and K.S. performed scanning electron microscopy measurements. D.H. performed ultraviolet–visible measurements. F.K. wrote the manuscript and all authors contributed to the writing of the manuscript.

Competing financial interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to:

Reviewer Information Nature thanks J. Smay and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Author details

Extended data figures and tables

Extended Data Figures

  1. Extended Data Figure 1: Characterization of the nanocomposite processing. (89 KB)

    a, Thermal gravimetric analysis of the cured nanocomposite used for stereolithography. The sample had a solid loading of 37.5 vol% SiO2. b, Corresponding heating programme for thermal debinding (I) and sintering (II) used for the composite shaped using stereolithography. c, Stereolithography cure depth (depth of a voxel upon exposure, corresponding to the penetration of the polymerization front during exposure) versus the laser power. The nanocomposites are highly stable and can be used for weeks with the same polymerization parameters.

  2. Extended Data Figure 2: Material and surface characterization of sintered glass. (171 KB)

    a, X-ray photoelectron spectroscopy narrow scans of elemental lines of printed and sintered glass compared to commercial fused silica glass. All spectra show virtually no difference between sintered fused silica glass and commercial fused silica glass. b, X-ray diffraction measurement shows that no devitrification occurs during the sintering process. Devitrification would present in the form of narrow peaks and spikes in the spectrum. c, Fourier transform infrared (FTIR) measurements of sintered glass compared to commercial fused silica glass.

Supplementary information

Video

  1. Video 1: Three-dimensional printing of glass (17.9 MB, Download)
    The video gives a short introduction into the printing process of the nanocomposite, the thermal debinding and the sintering process.

PDF files

  1. Supplementary Information (110 KB)

    This file contains Supplementary Text.

Additional data