The SEMATECH Berkeley microfield exposure tool: learning at the 22-nm node and beyond

Microfield exposure tools (METs) continue to play a dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the SEMATECH Berkeley 0.3-NA MET operating as a SEMATECH resist and mask test center. Here we present an update summarizing the latest resist test and characterization results. The relatively small numerical aperture and limited illumination settings expected from 1st generation EUV production tools make resist resolution a critical issue even at the 32-nm node. In this presentation, sub 22 nm half pitch imaging results of EUV resists are reported. We also present contact hole printing at the 30-nm level. Although resist development has progressed relatively well in the areas of resolution and sensitivity, line-edge-roughness (LER) remains a significant concern. Here we present a summary of recent LER performance results and consider the effect of system-level contributors to the LER observed from the SEMATECH Berkeley microfield tool.

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