Snapshot phase sensitive scatterometry based on double-channel spectral carrier frequency concept.

Area of Science:

• Optical Nano-metrology
• Spectroscopic Ellipsometry
• Nanoscale Structure Measurement

Background:

• Spectroscopic ellipsometry is crucial for thin film and nano pattern 3D structure analysis.
• Existing methods can be time-consuming for dynamic measurements.
• There is a need for rapid, high-accuracy metrology in nanotechnology.

Purpose of the Study:

• To propose a novel snapshot phase-sensitive normal incidence spectroscopic ellipsometric scheme.
• To enable simultaneous measurement of ellipsometric parameters Ψ(λ) and Δ(λ).
• To demonstrate the capability for 3D nanostructure characterization.

Main Methods:

• Development of a double-channel spectral carrier frequency concept.
• Simultaneous acquisition of two spectra through dual spectroscopic channels.
• Experimental validation using a binary grating with nanoscale 3D structure.

Main Results:

• Successful measurement of Ψ(λ) and Δ(λ) using only two acquired spectra.
• Demonstrated experimental efficacy on a 3D nanostructured binary grating.
• Achieved snapshot spectroscopic ellipsometric parameter measurement with moderate accuracy.

Conclusions:

• The proposed double-channel spectral carrier frequency method offers a snapshot capability for spectroscopic ellipsometry.
• This technique is effective for measuring 3D nanostructures.
• The method provides a valuable tool for optical nano-metrology with improved speed.