Recent progress of EUV Full Field Exposure Tool in Selete

摘要

The Selete full-field EUV exposure tool, the EUV1, was manufactured by Nikon and is being set up at Selete. Its lithographic performance was evaluated in exposure experiments with a static slit using line-&-space (L&S) patterns, Selete Standard Resist 03 (SSR3), an NA of 0.25, and conventional illumination (σ = 0.8). The results showed that 25-nm L&S patterns were resolved. Dynamic exposure experiments showed the resolution to be 45 nm across the exposure field and the CD uniformity across a shot to be 3 nm, also 26-nm L&S patterns were resolved.Overlay performance of the EUV1 was showed as processed wafer mark alignment, the repeatability was under 1nm. Overlay accuracy using EGA (Enhanced Global Alignment) was below 4nm at the 3-sigma after liner correction. These results were good enough for an alpha-level lithography tool and test site verification.