Optical properties of nanostructured WO3 thin films by GLancing Angle Deposition: Comparison between experiment and simulation

Optical properties (refractive index and birefringence) of WO3 thin films exhibiting columnar and zigzag nanostructures deposited by Glancing Angle Deposition are analyzed. The influence of the incident angle alpha of the sputtered particles and the number of zigzags Non these optical properties is determined. The experimental results show that refractive index of zigzag nanostructures evolves with the number of zigzags from n(N) (=) (0.5) = 2.02 to n(N) (= 8) = 2.05 through a maximum n(N) (= 4) = 2.29. The birefringence of columnar structures exhibits a similar trend when alpha changes from 0 to 80 degrees. Birefringence of columnar and zigzag structures reaches both a maximum when alpha = 50 degrees (Delta n(alpha) (=) (50 degrees) = 0.025). Experimental results favorably agree with the simulated ones calculated by means of the MEEP FDTD code. (C) 2015 Elsevier B.V. All rights reserved.