Application of new development technology to ultra-narrow pitch patterns formed by electron beam lithography

Although the latest EUV exposure systems are essential for next-generation lithography such as High-NA and Hyper-NA, access to them remains difficult even for basic experiments. Therefore, we focused on Electron Beam (EB) lithography, which is capable of sub-10 nm patterning, to investigate its potential applicability for early-stage process development in the High-NA era. Correlation studies between EUV and EB lithography revealed linear relationships when the underlayer was fixed, but the correlations responded differently to changes in the underlayer. Authors think that these findings provide insights into critical considerations when adopting EB lithography as a substitute for EUV. Additionally, we demonstrated two types of new development methods on narrow pitch patterns equivalent to High-NA scales: Line-and-Space (LS) patterns with pitch 16 nm and pillars (PL) patterns with pitch 20 nm. Both patterns showed reduced pattern collapse and defect generation under these new development methods, indicating that the new techniques are promising candidates for the High-NA era. Simultaneously, these results suggest that EB lithography can become a practical platform for evaluating process technologies at narrow pitches.