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Additive Manufacturing of High-Refractive-Index, Nanoarchitected Titanium Dioxide for 3D Dielectric Photonic Crystals

May 22, 2020

Research Overview

Andrey Vyatskikh

Graduate student and Resnick Fellow, Andrey Vyatskikh, is a member of a research team that developed an additive manufacturing (AM) process to fabricate complex 3D architectures out of titanium dioxide (titania, TiO2), with a refractive index of 2.3 and nanosized critical dimensions. The results of this study are summarized in the publication, "Additive Manufacturing of High-Refractive-Index, Nanoarchitected Titanium Dioxide for 3D Dielectric Photonic Crystals", and notes the process can be applied to directly fabricate a broad range of 3D architectures and is not limited to TiO2. The developed AM process enables advances in 3D microelectromechanical systems (MEMS), micro-optics, and prototyping of 3D dielectric photonic crystals (PhCs).

Scientific Achievement

We developed an additive manufacturing (AM) process for titanium dioxide (titania, TiO2) with ~100 nm resolution

Process for nanoscale additive manufacturing (AM) of titanium dioxide (left) and SEM characterization of as-fabricated TiO2 3D architectures (right)
Process for nanoscale additive manufacturing (AM) of titanium dioxide (left) and SEM characterization of as-fabricated TiO2 3D architectures (right) Credit: Reprinted with permission from ACS Nano Letters: DOI:10.1021/acs.nanolett.0c00454

Significance and Impact

Additive manufacturing of 3D nanoarchitected titania will enable facile fabrication of components for micro-optics, 3D MEMS, minimally invasive tools and procedures, and photocatalysis

Optical characterization of 3D photonic crystals fabricated using the developed nanoscale AM process. Left: A schematic of a woodpile unit cell and the corresponding Brillouin zone Center: Calculated band structure of the fabricated woodpile FCT architecture. The gray band shows the position of a full photonic band gap. Right: FTIR reflectance spectra for as-fabricated woodpile structures with varying periodicities showing passive tuning of the reflectance band position between 1.8 and 2.4 μm.
Optical characterization of 3D photonic crystals fabricated using the developed nanoscale AM process. Left: A schematic of a woodpile unit cell and the corresponding Brillouin zone Center: Calculated band structure of the fabricated woodpile FCT architecture. The gray band shows the position of a full photonic band gap. Right: FTIR reflectance spectra for as-fabricated woodpile structures with varying periodicities showing passive tuning of the reflectance band position between 1.8 and 2.4 μm. Credit: Reprinted with permission from ACS Nano Letters: DOI:10.1021/acs.nanolett.0c00454

Technical Details

  • 120-600 nm features with <1% porosity.
  • Rutile phase of nanocrystalline TiO2 w/ 120nm grain size
  • Process precision allowed to fabricate 3D dielectric photonic crystals with full photonic bandgap in the infrared

A. Vyatskikh, R.C. Ng, B. Edwards, R.M. Briggs, J.R. Greer. (2020) Additive Manufacturing of High-Refractive-Index, Nanoarchitected Titanium Dioxide for 3D Dielectric Photonic Crystals. ACS Nano Letters, 20, 5, 3513–3520. DOI: https://doi.org/10.1021/acs.nanolett.0c00454

Contact: Julia R. Greer