{"id":197372,"date":"2025-10-09T16:09:44","date_gmt":"2025-10-09T16:09:44","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/diffraction-based-overlay-metrology-system-design\/"},"modified":"2025-10-09T16:09:51","modified_gmt":"2025-10-09T16:09:51","slug":"diffraction-based-overlay-metrology-system-design","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/diffraction-based-overlay-metrology-system-design\/","title":{"rendered":"Diffraction-Based Overlay Metrology System Design"},"content":{"rendered":"<p>In the semiconductor industry, the alignment of the different layers used in lithography is essential. Overlay metrology systems allow to measure the eventual misalignment (overlay) that can happen during manufacturing. In this example, we demonstrate how to model a complete diffraction-based overlay metrology system \u00e2\u20ac\u2022 from the illumination through the diffraction grating to the collection \u00e2\u20ac\u2022 and how to estimate the measurement accuracy through overlay calculation. The nano-scale targets are designed with Ansys Lumerical RCWA and the lens system is modeled in Ansys Zemax OpticStudio, while leveraging the dynamic link between RCWA and OpticStudio workflow and optimization.<br \/>\nRead the full article here: <a target=\"_blank\" href=\"https:\/\/optics.ansys.com\/hc\/en-us\/articles\/24013763098259\" rel=\"noopener\">https:\/\/optics.ansys.com\/hc\/en-us\/articles\/24013763098259<\/a><\/p>\n","protected":false},"template":"","class_list":["post-197372","topic","type-topic","status-publish","hentry","topic-tag-lumericalzemax"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":[""],"_bbp_topic_id":[""],"_bbp_last_active_time":[""],"_bbp_author_ip":["184.24.96.186"],"_wp_page_template":["default"],"_btv_view_count":["253"]},"test":"solution"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics\/197372","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":1,"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics\/197372\/revisions"}],"predecessor-version":[{"id":197413,"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics\/197372\/revisions\/197413"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/media?parent=197372"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}