Nulling-Zone Ellipsometry

Spectroscopic ellipsometry is a noncontact and nondestructive optical technique for thin thin film characterization. It can be used to measure most material types: dielectrics, semiconductors, metals, superconductors, polymers, biological coatings, and even multilayers of these materials.

Our  ellipsometer is a EP3SW imaging, zero-nulling ellipsometer from Accurion. It covers the spectral range from 360 to 1000 nm, by using a wheel of narrow filters in front of a Xe lamp.

What can be done with this setup?

• Determination of optical material properties (refractive index, extinction coefficient)
• Determination of the layer thickness of very thin films in the range of 1 nm and a few micrometer
• Ellipsometric porosimetry: a technique that allows the investigation of porosity in thin films. It involves the construction of an adsorption isotherm based on the change in refractive index of the sample at various relative humidities.
• Flow cell for the in-situ (real-time) characterization of adsorption processes in a liquid environement.
• Electrochemical solid-liquid cell for in-situ electrochemical measurements of non-transparent samples in a liquid environment.