Recent results from EUVL patterned mask inspection using projection electron microscope system

The recent status of a newly developed PEM pattern inspection system for hp 16 nm node defect detection is presented. A die-to-die defect detection sensitivity of the developing system is also 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 “withdefects” to the PEM images “without-defects”. This image-processing system was also developed for die-to-die inspection. Captured images of extrusion and intrusion defects in hp 64 nm L/S pattern were used for detection. 12 nm sized intrusion defect, that was smaller than 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 for hp 11 nm EUVL patterned mask inspection, defect detection signal characteristics, which depend on hp 64 nm pattern image intensity deviation on EUVL mask, was studied.