How does spectroscopic ellipsometry work?

Answer: Spectroscopic ellipsometry measurements determine the change in polarization for a light beam reflecting or transmitting from a surface. If the measurement system and sample are ideal, the incoming and detected light are both fully polarized.

What does ellipsometry measure?

Ellipsometry measures a change in polarization as light reflects or transmits from a material structure. The polarization change is represented as an amplitude ratio, Ψ, and the phase difference, Δ. The measured response depends on optical properties and thickness of individual materials.

How does ellipsometry measure thickness?

Ellipsometry is a technique often used to measure the thickness of a thin film. Generally speaking, the measurement is performed by polarizing an incident light beam, reflecting it off a smooth sample surface at a large oblique angle and then re-polarizing the light beam prior to its intensity measurement.

What types of thin film coatings can spectroscopic ellipsometry measure?

Ex-situ spectroscopic ellipsometry allows for the characterization of a range of thin film properties including layer thickness, surface roughness thickness, interface thickness, optical constants, composition, band gap, composition, crystallinity, grading, anisotropy, and uniformity by depth and area.

Who invented ellipsometry?

Paul Drude
The technique of ellipsometry was invented by Paul Drude in 1887 who used it to determine the dielectric function of various metals and dielectrics. For 75 years following Drude’s pioniering work only a handful of ellipsometric studies were done.

Is ellipsometry destructive?

As an optical technique, spectroscopic ellipsometry is non-destructive and contactless.

What is spectroscopic ellipsometry?

Spectroscopic ellipsometry has become a standard method among the polarization-dependent optical techniques to explore the optical properties of solids and liquids.† However, until today most of the results obtained with ellipsometry are reported from isotropic materials.

What information can be obtained from ellipsometry?

Ellipsometry provides information about: Film thickness Optical properties Surface roughness Interfacial mixing Composition Crystallinity Anisotropy Depolarization Uniformity by both depth and area Film Interface Substrate Surface © 2007 HORIBA, Ltd. All rights reserved.© 2012 HORIBA, Ltd.  All rights reserved.

Do you need a compensator for a spectroscopic ellipsometer?

For many spectroscopic ellipsometers, no compensator (or quarter-wave plate) is used. We simply toss out the data for those wavelengths where Δ is near zero or 180° and do our regression analysis with the remainder of the data. Two such configurations are shown in Figure 4.21. Figure 4.21.