一种正交偏振图像中对称与非对称信号的分离方法与系统
By generating common-polarization and cross-polarization frequency domain images through an optical imaging module, and separating symmetric and asymmetric signals using a rigorous coupled-wave analysis method, the problems of low efficiency and insufficient accuracy in traditional overlay error measurement are solved, and efficient and accurate overlay error extraction is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HUAZHONG UNIV OF SCI & TECH
- Filing Date
- 2025-11-05
- Publication Date
- 2026-07-17
AI Technical Summary
In sub-nanometer manufacturing, existing technologies cannot effectively decouple critical dimensions and overlay error information using traditional overlay error measurement methods, resulting in low extraction efficiency and limited accuracy. Overlay error measurement is particularly difficult in high-density transistor structures.
The optical imaging module generates common-polarization and cross-polarization frequency domain images. A positive optical characteristic model is established using the rigorous coupled-wave analysis method. Image transformation operations are performed to separate symmetrical and asymmetrical signals and extract overlay errors.
It achieves accurate separation of symmetrical and asymmetrical signals in orthogonal polarization frequency domain images, significantly improves the extraction efficiency and accuracy of edge placement error parameters, is suitable for high-precision nanometer measurements, and maintains the simplicity and ease of implementation of the method.
Smart Images
Figure CN121301849B_ABST