NIST logo

Publication Citation: Towards High Accuracy Reflectometry for Extreme-Ultraviolet Lithography

NIST Authors in Bold

Author(s): Charles S. Tarrio; S Grantham; M B. Squires; Robert E. Vest; Thomas B. Lucatorto;
Title: Towards High Accuracy Reflectometry for Extreme-Ultraviolet Lithography
Published: July 01, 2003
Abstract: Currently the most demanding application of extreme ultraviolet optics is connected with the development of extreme ultraviolet lithography. Not only does each of the Mo/Si multilayer EUV stepper mirrors require the highest attainable reflectivity at 13 nm (nearly 70%), but the central wavelength of the reflectivity of these mirrors must be measured to a precision of 0.001 nm and peak reflectivity of the reflective masks to a precision of 0.12%. We report on two upgrades of our NIST/DARPA Reflectometry Facility that have given us the ability to achieve 0.1% precision and 0.3% absolute accuracy in our reflectivity measurements. A third upgrade, a monochromator with thermal and mechanical stability for improved wavelength precision, is currently in the design phase.
Citation: Journal of Research (NIST JRES) -
Volume: 108 No. 4
Keywords: extreme ultraviolet;lithography;metrology;reflectometry;synchrotron radiation
Research Areas: