At-wavelength interferometry for extreme ultraviolet lithography
At-wavelength interferometry for extreme ultraviolet lithography
复制标题
用于极紫外光刻的波长干涉测量
DOI：
10.1116/1.589666
复制
发表时间：
1997
影响因子：
1.4
通讯作者：
D. Attwood
中科院分区：
文献类型：
--
作者：
E. Tejnil;K. Goldberg;S. Lee;H. Medecki;P. Batson;P. Denham;A. MacDowell;J. Bokor;D. Attwood
本文介绍了一种用于极紫外光刻光学系统波长检测的移相点衍射干涉仪。利用该干涉仪测量了10× Schwarzschild多层膜反射光学系统在13.4nm工作波长下的像差。彩色渐晕效应的观察，他们证明了多层膜的波前上的影响。具有0.07的数值孔径的光学器件的子孔径被测量为在13.4nm波长处具有0.090波（1.21nm）均方根（rms）的波前误差。波前测量表明测量重复性为±0.008波（±0.11 nm）rms。包括测量像差影响的图像计算与使用10× Schwarzschild光学器件在极紫外线曝光工具上进行的成像一致。
A phase-shifting point diffraction interferometer is being developed for at-wavelength testing of extreme ultraviolet lithographic optical systems. The interferometer was implemented to characterize the aberrations of a 10× Schwarzschild multilayer-coated reflective optical system at the operational wavelength of 13.4 nm. Chromatic vignetting effects are observed and they demonstrate the influence of multilayer coatings on the wave front. A subaperture of the optic with a numerical aperture of 0.07 was measured as having a wave front error of 0.090 wave (1.21 nm) root mean square (rms) at a 13.4 nm wavelength. The wave front measurements indicate measurement repeatability of ±0.008 wave (±0.11 nm) rms. Image calculations that include the effects of the measured aberrations are consistent with imaging performed with the 10× Schwarzschild optic on an extreme ultraviolet exposure tool.