Direct fabrication of a metal-like TiN-based plasmonic grating using nitridation of a photo-patternable TiO_2 sol-gel film

L. Berthod (1) , V. Gâté (1) , M. Bichotte , M. Langlet (2) , F. Vocanson (1) , Carmen Jiménez (2) , D. Jamon (2) , I. Verrier (1) , C. Veillas (1) , O. Parriaux (1) , Y. Jourlin (1)

1 LHC - Laboratoire Hubert Curien
2 LMGP - Laboratoire des matériaux et du génie physique

We propose to combine a few known technologies to print TiOxNy quasi-sinusoidal grating using a direct photo-patternable TiO2 sol-gel thin layer, enabling the conversion of a pure dielectric grating to a metallic one. An expanded laser beam illuminates a photosensitive TiO2 sol-gel layer through a photo-mask grating, creating illuminated and non-illuminated areas in the sol-gel layer, which act as a negative photoresist and leads to a TiO2 based grating. Nitridation is made by heat treatment under NH3 flow to convert TiO2 in TiOxNy grating. This process shows that the sol-gel technology can be extended from a dielectric to metallic layer. The derived meta-material offers an alternative for plasmonic effects in the near-infrared region. This paper describes the experimental processes from the photochemistry of the TiO2 sol-gel layer to its nitridation. Thanks to the optical properties of the obtained micrometric period TiOxNy grating, surface plasmon resonance at TiOxNy-air interface has been excited in the NIR range (around 1500 nm), demonstrating the metallic behavior of the grating and its ability to be used as a plasmonic component.

Mots clés: plasmonic; TiN; sol-gel; grating

Domaines: Physique [physics]

L. Berthod, V. Gâté, M. Bichotte, M. Langlet, F. Vocanson, et al.. Direct fabrication of a metal-like TiN-based plasmonic grating using nitridation of a photo-patternable TiO_2 sol-gel film. Optical Materials Express, 2016, 6 (8). ⟨hal-01381751⟩