EUV patterned mask inspection performance of an advanced Projection Electron Microscope (PEM) system for hp 16 nm and beyond

The framework and the current status of a newly developed PEM pattern inspection system are presented. A die-to-die defect detection sensitivity of the developing system is investigated. A programmed defect mask was used for demonstrating the performance of the system. Defect images were obtained as difference images by comparing the PEM images "with-defects" to the PEM images "without-defects". The image-processing system was also developed for die-to-die inspection. A targeted inspection-throughput of 19-hour inspection per mask with 16 nm pixel size for image capture was attained. Captured images of extrusion and intrusion defects in hp 64 nm L/S pattern were used for detection. Then 16 nm sized intrusion defect, which was our target size for hp 16 nm defect detection requirement, was identified without false defects. To improve the performance of hp 16 nm patterned mask inspection, defect detection requirements for hp 11 nm EUVL patterned mask inspection was studied.