Work

High-Sensitivity Defect Inspection for Unpatterned Wafers via Integrating Dark-Field Scattering and Diffraction Phase Microscopy

Year: 2026

Type: article

Abstract: To overcome the limitations in the sensitivity and reliability of conventional wafer defect inspection techniques, a novel dual-channel optical inspection system is proposed by combining dark-field scattering with diffraction phase microscopy. Such an integrated system simultaneously acquires dark-field intensity and phase gradient signals arising from wafer defects, enabling comprehensive defect characterization at identical wafer locations while maintaining high sensitivity and high efficiency. Experimental validation using polystyrene particles demonstrates that the system achieves a limit of detection of 60 nm, improves the detecting sensitivity compared to single dark field scattering systems, and maintains the lateral/vertical limit of detection for small-scale defects. These results confirm its potential to meet the high-sensitivity and high-reliability requirements of unpatterned wafer defect inspection for advanced semiconductor manufacturing.

Source: Sensors

DOI: 10.3390/s26041271

Authors: Xiangchao Zhang, Qianru Zheng, Di Li, Ruifang Ye

Institutions: Fudan University, Aviation Industry Corporation of China (China), Huaqiao University

Language: English

Topic: Industrial Vision Systems and Defect Detection

Subfield: Industrial and Manufacturing Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funder: National Natural Science Foundation of China