应用于22nm及以下节点的极紫外光刻胶研究进展

Recent Advancements of EUV Resist for 22 nm Half-pitch and Below

极紫外光刻(EUVL)是最有希望用于22 nm及以下节点的下一代光刻技术,光刻胶的性能与工艺是其关键技术之一。EUV光刻胶应同时满足高分辨率、低线边缘粗糙度和高灵敏度的要求。回顾了应用于22 nm及以下技术节点的EUV光刻胶的发展现状和面临的挑战,介绍了EUVL对光刻胶的基本要求以及分辨率、线边缘粗糙度(LER)和灵敏度之间的平衡关系,阐述了LER的形成机理尤其是LER的降低,从产酸剂、吸收增强、分子尺寸的缩小、酸扩增、酸的各向异性扩散等材料设计方面总结了可能的光刻胶性能改进方案,探讨了EUV光刻胶未来的主要研究方向。

Extreme ultraviolet lithography（ EUVL） is one of the most promising candidates for next-generation lithography beyond the 22 nm half-pitch. High performance EUV resist continue to be one of the most critical challenges for EUVL technology implementation. The key challenge for EUV resist is the simultaneous requirement of ultrahigh resolution,low line edge roughness（ LER） and high sensitivity for lines and spaces features,the trade-off of which restricts the resist performance. The status and challenges of resist materials for 22 nm node and below are reviewed. The trade-off relationship between EUV resist targets,namely,resolution,LER,and sensitivity are described and reviewed. The mechanisms of LER formation and the reduction of LER are discussed. The effect and possible solutions to the improvement of EUV resist performance are discussed by acid generator,absorption enhancement,reduction in molecular size,acid amplification,anisotropic acid diffusion in material design.