World Class Ellipsometer: Woollam VASE
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Thin-film thickness: 1 nm to 1 µm, uniquely accurate
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Wide spectra optical constant, refractive index (n, k)
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Band gap
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Density profile along the thin film cross-section
Unique Optical Reverse Engineering
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Unique measurement methods
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Plus Software simulation: Optilayer and Woollam W-VASE
Ellipsometry (SE) + Transmittance (T) accuracy much improved
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SE+T provides much more accurate thickness, n,k properties than those measured by SE alone
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Additional information (such as gradience) could be ​​obtained.
SE + T + Res (sheet resistance)
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SE+T+Res provide more accurate thickness, n,k
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Additional information that could be ​​obtained accurately,
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​Gradience
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Carrier density
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Carrier mobility​
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Spectral ellipsometry measures the characteristics like thickness, refractive index, extinction coefficient of transparent films, making it essential to the development of thin film stacks without having to fabricate cumbersome test structures. Ellipsometry is a complex technique that yields rich data when combined with powerful modelling by the senior expert in the field.
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Applications: Optics (laser, coatings, electrochromic and photochromic coatings), displays, anti-reflective and high-reflection coatings, semiconductors, photosensitive materials
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Measurements: From the raw collected data, advanced modeling allows to extract
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Generalized Ellipsometry (Anisotropy, Retardance, Birefringence)
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Optical constants: refractive index (n), extinction coefficient (k), and reflectance (R) and transmittance (T) intensity
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Film thickness 1nm-1um (~Å accuracy)
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Electron mobility and density along the cross section
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Band gap
Instrument: J.A. Woollam VASE (variable angle spectroscopic ellipsometry). J.A.Woollam is the reference manufacturer of spectral ellipsometers, and the VASE model is currently the gold standard in the field: versatile and accurate. This instrument combines high accuracy and precision with a wide spectral range.