VASE Ellipsometer Home Page - J.A. Woollam Co.






The VASE is our most accurate and versatile ellipsometer for research on all types of materials: semiconductors, dielectrics, polymers, metals, multi-layers, and more.

It combines high accuracy and precision with a wide spectral range up to 193 to 3200nm. Variable wavelength and angle of incidence allow flexible measurement capabilities including:

• Reflection and Transmission Ellipsometry
• Generalized Ellipsometry
• Reflectance (R) intensity
• Transmittance (T) intensity
• Cross-polarized R/T
• Depolarization
• Scatterometry
• Mueller-matrix


VASE Ellipsometer with glass sample

VASE ellipsometer with patterned sample

Why a VASE?

Maximum Data Accuracy
The VASE features a rotating analyzer ellipsometer (RAE) combined with our patented AutoRetarder® for unparalleled data accuracy.

High Precision Wavelength Selection
The HS-190™ scanning monochromator is designed specifically for spectroscopic ellipsometry. It optimizes speed, wavelength accuracy, and light throughput, while automatically controlling selection of wavelengths and spectral resolution.

Flexible Measurements
The V-VASE features a vertical sample mount to accommodate a large variety of measurement geometries including reflection, transmission, and scattering.


RAE + AutoRetarder Technology
Rotating Analyzer Ellipsometers (RAE) maximize data accuracy near the “Brewster” condition - where Ψ/Δ data are content-rich. However, this region can be limiting for samples with reduced signal.

The patented AutoRetarder is a computer controlled waveplate which modifies the light beam polarization before it reaches the sample. This produces optimum measurement conditions for any sample, under any conditions.

AutoRetarder accurately measures:
• Ψ and Δ over the full range!
• Generalized (anisotropic) Ellipsometry
• Depolarization data
• Mueller-matrix data

AutoRetarder Diagram


© 2016 J.A. WOOLLAM CO. INC.
LINCOLN, NE 68508-2243 USA
Ph. 402.477.7501 | Fx. 402.477.8214