Fast scanning quantitative phase microscopy with an infinite field of view

The optical phase imaging technique has been demonstrated as a powerful tool for diverse disciplines such as material characterization and nanomanufacturing. In semiconductor metrology, phase imaging is considered superior to traditional bright field imaging due to its strong contrast. However, traditional phase imaging methods, which rely on task segmentation and image stitching, are undoubtedly inadequate for detection tasks in the high-efficiency production lines of integrated circuits. In this report, inspired by flow cytometry, we developed a Fast Scanning Quantitative Phase Microscope, which integrates a novel pixelated data acquisition strategy, a horizontal phase-shifting technique, and a robust phase reconstruction algorithm to enable a theoretically infinite field of view (FOV) without sacrificing optical resolution. We experimentally demonstrated the high-precision and large-scale phase imaging capability by accurately measuring 200nm-deep etched holes on a homemade wafer, showcasing its potential for semiconductor and bio-imaging applications.