Tarrio Charles, Grantham Steven, Squires Matthew B, Vest Robert E, Lucatorto Thomas B
National Institute of Standards and Technology, Gaithersburg, MD, 20899-8410 USA.
J Res Natl Inst Stand Technol. 2003 Aug 1;108(4):267-73. doi: 10.6028/jres.108.025. Print 2003 Jul-Aug.
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 extreme-ultraviolet 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 with a wavelength repeatability of 0.001 nm and the peak reflectivity of the reflective masks with a repeatability of 0.12 %. We report on two upgrades of our NIST/DARPA Reflectometry Facility that have given us the ability to achieve 0.1 % repeatability and 0.3 % absolute uncertainty in our reflectivity measurements. A third upgrade, a monochromator with thermal and mechanical stability for improved wavelength repeatability, is currently in the design phase.
目前，极紫外光学最具挑战性的应用与极紫外光刻技术的发展相关。不仅每个钼/硅多层极紫外步进光刻机反射镜都需要在13纳米处具备尽可能高的反射率（接近70%），而且这些反射镜的反射率中心波长必须以0.001纳米的波长重复性进行测量，反射掩膜的峰值反射率需以0.12%的重复性进行测量。我们报告了美国国家标准与技术研究院/美国国防部高级研究计划局反射测量设施的两次升级情况，这使我们能够在反射率测量中实现0.1%的重复性和0.3%的绝对不确定度。第三次升级是一台具备热稳定性和机械稳定性以提高波长重复性的单色仪，目前正处于设计阶段。
