Fast Focus and Astigmatism Correction Algorithm for Critical Dimension Measurement using Electron Microscopy

다국어 초록 (Multilingual Abstract)

This study aims to suggest automatic detection and correction method of defocus and astigmatism in critical dimension measurement using electron microscopy with nanometer electron beams. To achieve this, the Fourier transform image is utilized for focus and astigmatism correction in critical dimension measurement using of electron microscopy. A novel algorithm is presented that analyzes this Fourier transform applied-image with adaptive image binarization and control electron beam and lens for simultaneous detection and correction to correct focus and astigmatism in real-time. Also, the accuracy of the algorithm is identified by applying the developed algorithm and measuring various specimens, and improvement in critical dimension performance is verified.