Structural and optical properties of cobalt slanted nanopillars conformally coated with few-layer graphene
Abstract
Optical characterization of anisotropic multicomponent nanostructures is generally not a trivial task, since the relation between a material's structural properties and its permittivity tensor is nonlinear. In this regard, an array of slanted cobalt nanopillars that are conformally coated with few-layer graphene is a particularly challenging object for optical characterization, as it has a complex anisotropic geometry and comprises several materials with different topologies and filling fractions. Normally, a detailed characterization of such complex nanostructures would require a combination of several microscopic and spectroscopic techniques. In this letter, we demonstrate that the important structural parameters of these graphene-coated sculptured thin films can be determined using a fast and simple generalized spectroscopic ellipsometry test combined with an anisotropic Bruggeman effective medium approximation. The graphene coverage as well as structural parameters of nanostructured thin films agree excellently with electron microscopy and Raman spectroscopy observations. The demonstrated optical approach may also be applied to the characterization of other nanostructured materials.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 08, 2015
- Source ID
- 10.1063/1.4922199
Entities
People
- Alexander Sinitskii
- Alexey Lipatov
- D. R. Schmidt
- Eva Schubert
- Mathias Schubert
- Peter M. Wilson
- Tino Hofmann
Organizations
- Army Research Office
- Division of Electrical, Communications & Cyber Systems
- Division of Materials Research
- Experimental Program to Stimulate Competitive Research