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Fabrication of Nanoheight Channels Incorporating Surface Acoustic Wave Actuation via Lithium Niobate for Acoustic Nanofluidics
Published on: February 5, 2020
Photonic crystal structures in ion-sliced lithium niobate thin films
Frederik Sulser1, Gorazd Poberaj, Manuel Koechlin
1Nonlinear Optics Laboratory, Institute of Quantum Electronics, ETH Zurich, 8093 Zurich, Switzerland.
Optics Express
|December 10, 2009
Summary
Researchers created novel photonic crystal structures using ion-sliced lithium niobate films and benzocyclobutene (BCB). This breakthrough enables strong light confinement for advanced photonic devices.
Area of Science:
- Materials Science
- Photonics
- Nanotechnology
Background:
- Lithium niobate (LiNbO3) is a key material for integrated optics.
- Fabricating complex photonic structures in thin-film LiNbO3 presents challenges.
- Benzocyclobutene (BCB) offers unique bonding and processing advantages.
Purpose of the Study:
- To demonstrate the first realization of photonic crystal structures in ion-sliced LiNbO3 thin films.
- To investigate the use of BCB as an adhesive layer and its effect on fabrication.
- To characterize the optical properties and photonic bandgap of the fabricated structures.
Main Methods:
- Utilized ion-slicing to obtain 600-nm thick single-crystalline LiNbO3 films.
- Employed focused ion beam (FIB) milling for rapid prototyping of photonic crystal lattices.
- Bonded LiNbO3 films to a LiNbO3 substrate using benzocyclobutene (BCB).
Main Results:
- Achieved regular cylindrical holes with minimized redeposition effects due to the BCB layer.
- Demonstrated high refractive index contrast (0.65) enabling strong vertical light confinement.
- Observed a photonic bandgap for TE-polarized light (1390-1500 nm) in a triangular lattice structure.
- Measured transmission spectra showing a spectral power dip with up to 15 dB extinction ratio, matching numerical simulations (PWE, FDTD).
Conclusions:
- Successfully fabricated and characterized photonic crystals in thin-film LiNbO3 using BCB.
- The BCB layer facilitates FIB milling and enhances light confinement.
- The results validate the potential of this approach for integrated photonic applications.
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