Process Development for and Fabrication of APSM Set and Overlay Metrology Wafers

The National Institute of Standards and Technology (NIST) is seeking information from contractors capable of providing at least four overlay metrology wafers made with attenuated phase shift masks (APSM) and the corresponding APSM mask set. The wafers should have specific patterns and properties, including box-in-box, image-based overlay, advanced imaging metrology grating patterns, and Hitachi-type SEM-based overlay patterns. The contractor should also provide documentation about the APSM properties, measurements, and images created during the fabrication process. Some key requirements for the project include: • Providing a minimum of four 300 mm Si wafers patterned with specific overlay metrology patterns • Including sets of varying size overlay metrology patterns in the less than 150 mm to smaller than 50 mm range • Providing overlay patterns with intentional, small, close to 1, 2, 5, and 10 nm variations of known overlay offsets • Delivering the wafers in a clean-room-compatible enclosure • Providing a GDSII-based map with pattern locations and properties at the time of delivery