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Updated: Jul 6, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Error analysis of null ellipsometry with depolarization.
1Physics Branch, Research and Technology Group, Weapons Division, Naval Air Warfare Center, China Lake, California 93555-6001, USA. neesf@navair.navy.mil
Applied Optics
|March 8, 2008
Summary
Null ellipsometry is sensitive to component depolarization and misalignment. Even small imperfections significantly impact accuracy, limiting its application range for precise measurements.
Area of Science:
- Optical physics
- Surface science
- Metrology
Background:
- Null ellipsometry is a technique for measuring optical properties.
- Component imperfections like depolarization and misalignment can affect measurement accuracy.
- Understanding these errors is crucial for reliable ellipsometric analysis.
Purpose of the Study:
- To analyze the impact of depolarization and other imperfections on null ellipsometry.
- To derive analytical solutions for null positions considering these errors.
- To simulate and validate the derived analytical solutions.
Main Methods:
- Analytical derivation of four-zone null positions to the second order of imperfections.
- Mueller matrix-based simulation incorporating depolarization.
- Analysis of the influence of sample depolarization (D), misalignment (deltaC), and retardance errors (deltatau).
Main Results:
- Errors in null positions increase with sample depolarization (D).
- Depolarization in components (except the analyzer) introduces errors.
- Errors couple with misalignment and retardance errors, amplified by csc(2) 2psi.
- Simulations show good agreement with analytical solutions.
Conclusions:
- Null ellipsometry accuracy is limited by component depolarization and misalignment.
- Strict control over sample depolarization and optical element quality is necessary.
- The study defines the applicable region for accurate null ellipsometry measurements.
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