Open AccessMicrostructure-related properties of magnesium fluoride films at 193nm by oblique-angle deposition
Author(s) -
Chaowei Guo,
Mingdong Kong,
Di Lin,
Cunding Liu,
Bincheng Li
Publication year - 2013
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.21.000960
Subject(s) - materials science , magnesium fluoride , microstructure , optics , refractive index , scanning electron microscope , crystallite , thin film , evaporation , attenuation coefficient , molar absorptivity , layer (electronics) , composite material , optoelectronics , nanotechnology , physics , metallurgy , thermodynamics
Magnesium fluoride (MgF2) films deposited by resistive heating evaporation with oblique-angle deposition have been investigated in details. The optical and micro-structural properties of single-layer MgF2 films were characterized by UV-VIS and FTIR spectrophotometers, scanning electron microscope (SEM), atomic force microscope (AFM), and x-ray diffraction (XRD), respectively. The dependences of the optical and micro-structural parameters of the thin films on the deposition angle were analyzed. It was found that the MgF2 film in a columnar microstructure was negatively inhomogeneous of refractive index and polycrystalline. As the deposition angle increased, the optical loss, extinction coefficient, root-mean-square (rms) roughness, dislocation density and columnar angle of the MgF2 films increased, while the refractive index, packing density and grain size decreased. Furthermore, IR absorption of the MgF2 films depended on the columnar structured growth.