Vapor-phase dry development enabling high-resolution and improved CDU in EUV photoresists

초록

High-numerical-aperture (high-NA) extreme ultraviolet (EUV) lithography requires advanced development processes capable of achieving both high resolution and superior critical dimension uniformity (CDU). Conventional wet development is often limited by solvent-induced forces and dissolution variability, which hinder precise CDU control in dense and isolated patterns such as squares and pillars, making it particularly challenging. In this study, we investigated a vapor-phase dry development process for a Zn-based metal–organic photoresist. Using hexafluoroacetylacetone (hfacH) vapor as the developer, line-and-space patterns were successfully resolved with a CD of 14nm. Compared to conventional wet development, the dry development process significantly reduced the CD variation from 3.21nm to 2.07nm, demonstrating a substantial improvement in CDU and pattern fidelity. These results suggest that vapor-phase dry development is a promising strategy for overcoming the physical limitations of high-NA EUV patterning.

키워드