Process performance comparisons on 300-mm i-line steppers, DUV stepper, and DUV scanners

SEMICONDUCTOR300 was the first pilot production facility for 300mm wafers in the world. This company, a joint venture between Infineon Technologies and Motorola, is working to develop a manufacturable 300mm wafer tool set. The lithography tools include I-line steppers, a DUV stepper, and two DUV scanners. These tools are used to build 64M DRAM devices and aggressive test vehicles. Data will be presented on the mix-and-matching performance between DUV scanners and I-line steppers. Process-related data on CD within-field and across wafer sampling for selected tool types were investigated. The process capability of the current tool set for 0.25 micrometers and 0.18 micrometers devices were compared. Resolution performance of the scanner with its 0.68 numerical aperture was studied. Dense and isolated printed pattern performance was measured with in-line metrology. 300mm wafers are sensitive to backside defectivity, and therefore the wafer chuck design plays an important role in achieving the desired pattern transfer performance. The performance of the different chuck types and their sensitivity to incoming backside wafer contamination levels was studied. Rework data was used to assist in characterizing the exposure dose matching and chuck type performance.