5 June 1998 Fabrication and testing of optics for EUV projection lithography
Author Affiliations +
EUV lithography (EUVL) is a leading candidate as a stepper technology for fabricating the '0.1 micrometers generation' of microelectronic circuits. EUVL is an optical printing technique qualitatively similar to DUV lithography (DUVL), except that 11-13 nm wavelength light is used instead of 193-248nm. The feasibility of creating 0.1 micrometers features has been well-established using small-field EUVL printing tools, and development efforts are currently underway to demonstrate that cost-effective production equipment can be engineered to perform full-width ring-field imaging consistent with high wafer throughput rates. Ensuring that an industrial supplier base will be available for key components and subsystems is crucial to the success of EUVL. In particular, the projection optics are the heart of the EUVL imaging system, yet they have figure and finish specifications that are beyond the state-of-the-art in optics manufacturing. Thus it is important to demonstrate that industry will be able to fabricate and certify these optics commensurate with EUVL requirements. Indeed, the goal of this paper is to demonstrate that procuring EUVL projection optical substrates is feasible. This conclusion is based on measurements of both commercially-available and developmental substrates. The paper discusses EUVL figure and finish specifications, followed by examples of ultrasmooth and accurate surfaces, and concludes with a discussion of how substrates are measured and evaluated.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
John S. Taylor, Gary E. Sommargren, Donald W. Sweeney, and Russell M. Hudyma "Fabrication and testing of optics for EUV projection lithography", Proc. SPIE 3331, Emerging Lithographic Technologies II, (5 June 1998); doi: 10.1117/12.309619; https://doi.org/10.1117/12.309619


Back to Top