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Title: Amplitude versus phase effects in extreme ultraviolet lithography mask scattering and imaging

Abstract

It is well established that extreme ultraviolet (EUV) mask multilayer roughness leads to wafer-plane linewidth roughness (LWR) in the lithography process. Analysis and modeling done to date has assumed, however, that the roughness leading to scatter is primarily a phase effect and that the amplitude can be ignored. Under this assumption, simple scattering measurements can be used to characterize the statistical properties of the mask roughness. Here, we explore the implications of this simplifying assumption by modeling the imaging impacts of the roughness amplitude component as a function of the balance between amplitude and phase induced scatter. In addition to model-based analysis, we also use an EUV microscope to compare experimental through focus data to modeling in order to assess the actual amount of amplitude roughness on a typical EUV multilayer mask. The results indicate that amplitude roughness accounts for less than 1% of the total scatter for typical EUV masks.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [2]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Center for X-Ray Optics
  2. Univ. of California, Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
OSTI Identifier:
1466703
DOE Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article
Journal Name:
Applied Optics
Additional Journal Information:
Journal Volume: 56; Journal Issue: 12; Journal ID: ISSN 0003-6935
Publisher:
Optical Society of America (OSA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats

Naulleau, Patrick P., Benk, Markus, Goldberg, Kenneth A., Gullikson, Eric M., Wojdyla, Antoine, Wang, Yow-Gwo, and Neureuther, Andy. Amplitude versus phase effects in extreme ultraviolet lithography mask scattering and imaging. United States: N. p., 2017. Web. doi:10.1364/AO.56.003325.
Naulleau, Patrick P., Benk, Markus, Goldberg, Kenneth A., Gullikson, Eric M., Wojdyla, Antoine, Wang, Yow-Gwo, & Neureuther, Andy. Amplitude versus phase effects in extreme ultraviolet lithography mask scattering and imaging. United States. doi:10.1364/AO.56.003325.
Naulleau, Patrick P., Benk, Markus, Goldberg, Kenneth A., Gullikson, Eric M., Wojdyla, Antoine, Wang, Yow-Gwo, and Neureuther, Andy. Fri . "Amplitude versus phase effects in extreme ultraviolet lithography mask scattering and imaging". United States. doi:10.1364/AO.56.003325.
@article{osti_1466703,
title = {Amplitude versus phase effects in extreme ultraviolet lithography mask scattering and imaging},
author = {Naulleau, Patrick P. and Benk, Markus and Goldberg, Kenneth A. and Gullikson, Eric M. and Wojdyla, Antoine and Wang, Yow-Gwo and Neureuther, Andy},
abstractNote = {It is well established that extreme ultraviolet (EUV) mask multilayer roughness leads to wafer-plane linewidth roughness (LWR) in the lithography process. Analysis and modeling done to date has assumed, however, that the roughness leading to scatter is primarily a phase effect and that the amplitude can be ignored. Under this assumption, simple scattering measurements can be used to characterize the statistical properties of the mask roughness. Here, we explore the implications of this simplifying assumption by modeling the imaging impacts of the roughness amplitude component as a function of the balance between amplitude and phase induced scatter. In addition to model-based analysis, we also use an EUV microscope to compare experimental through focus data to modeling in order to assess the actual amount of amplitude roughness on a typical EUV multilayer mask. The results indicate that amplitude roughness accounts for less than 1% of the total scatter for typical EUV masks.},
doi = {10.1364/AO.56.003325},
journal = {Applied Optics},
issn = {0003-6935},
number = 12,
volume = 56,
place = {United States},
year = {2017},
month = {12}
}

Works referenced in this record:

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