Optical properties of cobalt slanted columnar thin films passivated by atomic layer deposition

Authors

Daniel Schmidt, University of Nebraska-LincolnFollow
Eva Schubert, University of Nebraska-LincolnFollow
Mathias Schubert, University of Nebraska-LincolnFollow

Date of this Version

2012

Citation

APPLIED PHYSICS LETTERS 100, 011912 (2012); doi:10.1063/1.3675549

Comments

Copyright 2012 American Institute of Physics

Abstract

Optical properties of passivated metal slanted columnar thin films from cobalt within the visible spectral region are reported. Glancing angle deposition is utilized to grow slanted nano-columns which have been conformally coated with Al₂O₃ by a subsequent atomic layer deposition process. A generalized anisotropic Bruggeman effective medium approximation has been employed to analyze spectroscopic generalized ellipsometry data. The modified homogenization approach allows for determination of biaxial (monoclinic) optical and structural properties as well as fractions of three film constituents. The conformal alumina passivation layer preserves the pristine metal character of the nano-structures and prevents oxidation and aging effects.