Ellipsometry

Ellipsometry is an optical reflection or transmission experiment using polarized light in which the change of polarization due to interaction with the object of interest is measured. The separate consideration of orthogonal polarization eigenmodes provides amplitude- and phase information (the so called ellipsometric angles Ψ and Δ or more general the Mueller matrix elements). By numerical inversion of the measured data or by means of transfer-matrix based models including parameterized model functions, the following properties of materials, layers or even layer stacks can be obtained from the experimental data:

• Layer thickness
• Optical constants,
• Complex refractive index (real part n and extinction coefficient k), or
• Complex dielectric functions (real ε₁ and imaginary part ε₂)
• Electronic properties (Interband transitions, excitons, polaritons)
• Free-charge-carrier properties (plasmons)
• Lattice vibrations (phonons)
• Surface and interface properties (roughness, gradients, adsorbates, ...)
• Orientation of optical axes and birefringence in anisotrpe samples

The portfolio of modern applications is (almost) unlimited. Examples are:

• Anorganics and organics
• Metals, semiconductors, insolators (dielectrics), multiferroics, graphene
• Isotropic and anisotropic (uniaxial or biaxial) materials
• In-situ process control
• Lithography
• 3D-structures

Schematic setup of ellipsometry. (*only one element is mandatory)

Related textbooks:

• R.M.A. Azzam & N.M. Bashara
  Ellipsometry and Polarized Light
  North-Holland Pub. Co., 1977; ISBN 978-0444870162 (More Info)
  
  
• H. Fujiwara
  Spectroscopic Ellipsometry: Principles and Applications
  John Wileyn & Sons, 2007; ISBN 978-0470016084 (More Infos)
  
  
• K. Hinrichs & K.-J. Eichhorn (Eds.)
  Ellipsometry of Functional Organic Surfaces and Films
  Springer, 2014; ISBN 378-3642401282 (More Infos)
  
  
• M. Losurdo & K. Hingerl (Eds.)
  Ellipsometry at the Nanoscale
  Springer, 2013; ISBN 978-3642339561 (More Infos)
  
  
• A. Roeseler
  Infrared Spectroscopic Ellipsometry
  Akademie-Verlag, Berlin, 1990; ISBN 978-3055006234
  
  
• M. Schubert
  Infrared Ellipsometry on Semiconductor Layer Structures: Phonons, Plasmons, and Polaritons
  Springer Tracts in Modern Physics, Vol. 209, Springer, 2004; ISBN 978-3540232490 (More Infos)
  
  
• H.G. Tompkins & E.A. Irene (Eds.)
  Handbook of Ellipsometry
  William Andrew Pub., Springer, 2005; ISBN 978-3540222934 (More Infos)
  
  
• H.G. Tompkins &  W.A. McGahan
  Spectroscopic Ellipsometry and Reflectometry: A User's Guide
  John Wiley & Sons, 1999; ISBN 978-0471181729 (More Infos)
  
  
• H.G. Tompkins
  A User's Guide to Ellipsometry
  Dover Publications, 2006; ISBN 978-0486450285 (More Infos)
  (Originally published by Academic Press, 1993)