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Varible Angle Spectroscopic Ellipsometry

Ellipsometry system

Ellipsometry uses the principle that plane polarised light can become elliptically polarised upon reflection from a material system. It is through the analysis of this reflected light that information can be obtained on the material yielding both the optical constants, thickness, and interfacial roughness for thin film layers.Spectroscopic Ellipsometry is a well established technique for the optical investigation of material systems and is the tool of choice for many thin film metrology requirements. It is a non-destructive technique that can determine the complex Refractive Indices / Dielectric functions of complex material systems. Stacked film layers can be probed for the optical constants, thickness and interfacial roughness.


SOPRA GESP 5 Varible Angle Spectroscopic Ellipsometer.


GESPACK: automation and data acquisition
WinElli: data analysis, regressions and modelling


Instrument Spectral Range: 250 - 900 nm with a resolution : 0.05 nm at 313nm
Accessories: Microspot system reduces the beam size perpendicular to the plane of incidence to less than 300 microns.
Film thickness range: 0.1 nm to > 5 µm

Sample Project

Refractive index and thickness calculation of thin film SiO2


Spectroscopic ellipsometry: a historical overview Vedam, K. Source: Thin Solid Films, v 313-314, n 1-2, Feb. 1998, 1-9