High-precision visual calibration of motion stage positioning errors using adaptive Zernike moments

Area of Science:

• Optics and Photonics
• Metrology and Measurement Science
• Precision Engineering

Background:

• Precision motion platforms in lithography equipment require highly accurate error calibration.
• Traditional calibration methods often suffer from insufficient accuracy and operational complexity.

Purpose of the Study:

• To develop a more accurate and efficient visual calibration method for precision motion platform positioning errors.
• To enhance the reliability of lithography equipment calibration.

Main Methods:

• Characterizing platform motion using a high-precision array concentric circle calibration plate.
• Proposing a visual calibration method based on Adaptive gradient Zernike (A-Zernike) moments.
• Implementing adaptive sub-pixel edge acquisition using gradient sampling and Gaussian fitting.
• Analyzing system parameters and performing joint calibration.
• Constructing an image coordinate conversion model for error solution.

Main Results:

• The A-Zernike moment algorithm demonstrated a 47.41% improvement in edge detection accuracy compared to traditional methods.
• Maximum platform positioning error was reduced from 15.601 μm to 0.783 μm post-calibration.
• The method effectively improved the accuracy and reliability of precision motion platform error calibration.

Conclusions:

• The A-Zernike moments visual calibration method offers a significant advancement in precision motion platform error calibration for lithography.
• This technique addresses the limitations of traditional methods, providing enhanced accuracy and operational efficiency.
• The improved calibration accuracy is crucial for the advancement of semiconductor manufacturing processes.