Ellipsometry

What Is Ellipsometry?

Ellipsometry measures the change in polarization of light reflected from or transmitted through a material surface. By analyzing this change, ellipsometry determines the optical response of thin films and interfaces.

Because ellipsometry is extremely sensitive to nanometer- and sub-nanometer-scale changes, it is ideal for analyzing:

ultra-thin films
multilayer structures
surface modifications
transparent and semi-transparent coatings

The technique does not require physical contact and typically leaves the sample intact.

What Ellipsometry Measures

Ellipsometry provides quantitative information on:

Thin film thickness (often from sub-nanometer to micrometer range)
Refractive index (n)
Extinction coefficient (k)
Optical constants vs. wavelength
Layer structure and uniformity
Interface and surface layer properties (model-dependent)

Results are obtained through optical modeling that reflects the actual film structure.

Why Use Ellipsometry?

Ellipsometry is chosen when you need:

precise thickness control of thin films
non-destructive measurement
high sensitivity to small changes in surface or layer properties
characterization of transparent or semi-transparent films

Typical questions ellipsometry can answer:

Is the film thickness within specification?
Are layers uniform across the surface?
Did processing change optical properties?
Are there unexpected surface layers or oxidation?
How do optical constants differ between suppliers or batches?

Typical Application Scenarios

Thin Films & Coatings

Thickness and uniformity verification
Multilayer structure evaluation
Process optimization for deposition or coating

Semiconductor & Electronic Materials

Dielectric and conductive thin film characterization
Interface and surface oxide evaluation
Monitoring of fabrication steps

Optical & Transparent Materials

Refractive index measurement
Optical constant determination
Performance optimization for optical coatings

Surface Treatments & Oxide Layers

Evaluation of surface modification effectiveness
Growth or removal of oxide layers
Aging and environmental exposure studies

Failure Analysis & Troubleshooting

Identification of unexpected thin layers
Comparison of “good vs. failed” coatings
Correlation of thickness or optical changes with performance issues

Sample Types

Ellipsometry can be applied to:

thin films on flat substrates
coatings on glass, silicon, metals, or polymers
multilayer optical stacks
transparent or semi-transparent materials

Best results are obtained on smooth, reflective, or semi-transparent surfaces. Xinbodi evaluates sample suitability and modeling approach before analysis.

What You Will Receive

Each ellipsometry project is delivered with a clear, structured report designed for engineering and quality decisions. A typical deliverable includes:

project objective and sample description
measurement conditions and wavelength range
optical models and assumptions used
film thickness and optical constant results
comparison summaries (batch vs. batch, before vs. after processing)
interpretation linked to processing and performance
recommendations for optimization or complementary analysis

Why Choose Xinbodi for Ellipsometry?

Experience with thin films and multilayer optical modeling
Careful method and model selection based on material system
High sensitivity and repeatability for thickness measurement
Clear interpretation beyond raw fitting parameters
Support for R&D, QC, and failure investigations
Confidential handling of proprietary materials and data