Screening effects in metal sculptured thin films studied with terahertz Mueller matrix ellipsometry

T. Hofmann, S. Knight, D. Sekora, D. Schmidt, C. M. Herzinger, John A Woollam, E. Schubert, Mathias Schubert

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The anisotropic optical dielectric functions of a metal (cobalt) slanted columnar thin film deposited by electron-beam glancing angle deposition are reported for the terahertz (THz) frequency domain before and after the slanted columnar thin film was passivated by a conformal alumina coating. A simple effective medium dielectric function homogenization approach which describes isolated, electrically conductive columns rendering the thin film biaxial (orthorhombic) is used to model the observed optical responses. Upon passivating the slanted columnar thin film with a 3. nm thick alumina film an increase of both the real and the imaginary part of the dielectric function for all major polarizability directions is found and attributed to screening effects within the spatially coherent metal nanocolumns.

Original languageEnglish (US)
JournalApplied Surface Science
DOIs
StateAccepted/In press - Jul 31 2016

Fingerprint

Ellipsometry
Screening
Metals
Thin films
Aluminum Oxide
Alumina
Cobalt
Electron beams
Coatings

Keywords

  • Bruggeman effective medium
  • Generalized ellipsometry
  • Glancing angle deposition
  • Sculptured thin film
  • Terahertz

ASJC Scopus subject areas

  • Surfaces, Coatings and Films

Cite this

Screening effects in metal sculptured thin films studied with terahertz Mueller matrix ellipsometry. / Hofmann, T.; Knight, S.; Sekora, D.; Schmidt, D.; Herzinger, C. M.; Woollam, John A; Schubert, E.; Schubert, Mathias.

In: Applied Surface Science, 31.07.2016.

Research output: Contribution to journalArticle

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AU - Woollam, John A

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AU - Schubert, Mathias

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