Open AccessSimulating different manufactured antireflective sub-wavelength structures considering the influence of local topographic variations
Author(s) -
Dennis Lehr,
Michael Helgert,
Michael Sundermann,
Christoph Morhard,
Claudia Pacholski,
Joachim P. Spatz,
Róbert Brunner
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.023878
Subject(s) - anti reflective coating , optics , wavelength , transmittance , materials science , rigorous coupled wave analysis , conical surface , scattering , optoelectronics , layer (electronics) , diffraction grating , physics , nanotechnology , composite material
Laterally structured antireflective sub-wavelength structures show unique properties with respect to broadband performance, damage threshold and thermal stability. Thus they are superior to classical layer based antireflective coatings for a number of applications. Dependent on the selected fabrication technology the local topography of the periodic structure may deviate from the perfect repetition of a sub-wavelength unit cell. We used rigorous coupled-wave analysis (RCWA) to simulate the efficiency losses due to scattering effects based on height and displacement variations between the individual protuberances. In these simulations we chose conical and Super-Gaussian shapes to approximate the real profile of fabricated structures. The simulation results are in accordance with the experimentally determined optical properties of sub-wavelength structures over a broad wavelength range. Especially the transmittance reduction in the deep-UV could be ascribed to these variations in the sub-wavelength structures.