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Title: Demonstration Of Laser Plasma X-Ray Source With X-Ray Collimator Final Report CRADA No. TSB-1535-98

Abstract

X-ray lithography is a leading candidate for advanced semiconductor manufacturing when optical lithography techniques are no longer able to meet the resolution requirements for future generations of devices. The resolution limit is determined by diffraction of the illumination source by the features on the mask, and by the ability of the non-linear photoresist to accentuate variations in the exposure dose (contrast enhancement). With continued development of excimer laser technology at wavelengths of 248 run and 193 run and contrast enhancement techniques such as phase-shifting masks, it appears that the earliest insertion point for x-ray lithography would correspond to 0.13 μm minimum feature size devices, with pilot line manufacturing in the year 2001. JTC developed a high-brightness x-ray point source where x-rays were generated in a laser-produced plasma. The source used high intensity sub-nanosecond laser pulses PAS from an all-solid-state laser system, focused onto metal tape targets, to generate the plasma. The ability of such a source to meet wafer throughput and resolution depended critically on the distance from the source to the proximity mask, and on the size of the print field. The wafer throughput could be substantially improved by using an x-ray collimator to collect x-rays from a largermore » solid-angle. Such a collimator essentially transformed a segment of the spherical radiation pattern of the point source to a linear beam. As such, it more closely simulated the exposure geometry of the synchrotron source, and eliminated the 1 /D2 x-ray flux dependence so that the mask and wafer distance from the source became more flexible. This was important for integration of the source with x-ray steppers for step-and-repeat wafer printing. Collimation of x-rays at wavelengths around 11 A was not straightforward que to the relatively poor reflectivity of materials in this region, and due to the constraints of the local and global divergence. A group at Lawrence Livermore National Laboratory (LLNL) extensively studied the design of such a collimator, both from an x-ray optics aspect and from a materials aspect. X-rays from the source were reflected by special coatings deposited on the highly polished cone or paraboloid interior. The materials used and their thickness were optimized to give highest x-ray reflectance corresponding to the angle of incidence at any point on the mirror surface.« less

Authors:
 [1];  [2]
  1. JMAR Technology Company, San Diego, CA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1424640
Report Number(s):
LLNL-TR-746151
DOE Contract Number:  
AC52-07NA27344
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Grygier, R, and Lane, S. M.. Demonstration Of Laser Plasma X-Ray Source With X-Ray Collimator Final Report CRADA No. TSB-1535-98. United States: N. p., 2018. Web. doi:10.2172/1424640.
Grygier, R, & Lane, S. M.. Demonstration Of Laser Plasma X-Ray Source With X-Ray Collimator Final Report CRADA No. TSB-1535-98. United States. doi:10.2172/1424640.
Grygier, R, and Lane, S. M.. Fri . "Demonstration Of Laser Plasma X-Ray Source With X-Ray Collimator Final Report CRADA No. TSB-1535-98". United States. doi:10.2172/1424640. https://www.osti.gov/servlets/purl/1424640.
@article{osti_1424640,
title = {Demonstration Of Laser Plasma X-Ray Source With X-Ray Collimator Final Report CRADA No. TSB-1535-98},
author = {Grygier, R and Lane, S. M.},
abstractNote = {X-ray lithography is a leading candidate for advanced semiconductor manufacturing when optical lithography techniques are no longer able to meet the resolution requirements for future generations of devices. The resolution limit is determined by diffraction of the illumination source by the features on the mask, and by the ability of the non-linear photoresist to accentuate variations in the exposure dose (contrast enhancement). With continued development of excimer laser technology at wavelengths of 248 run and 193 run and contrast enhancement techniques such as phase-shifting masks, it appears that the earliest insertion point for x-ray lithography would correspond to 0.13 μm minimum feature size devices, with pilot line manufacturing in the year 2001. JTC developed a high-brightness x-ray point source where x-rays were generated in a laser-produced plasma. The source used high intensity sub-nanosecond laser pulses PAS from an all-solid-state laser system, focused onto metal tape targets, to generate the plasma. The ability of such a source to meet wafer throughput and resolution depended critically on the distance from the source to the proximity mask, and on the size of the print field. The wafer throughput could be substantially improved by using an x-ray collimator to collect x-rays from a larger solid-angle. Such a collimator essentially transformed a segment of the spherical radiation pattern of the point source to a linear beam. As such, it more closely simulated the exposure geometry of the synchrotron source, and eliminated the 1 /D2 x-ray flux dependence so that the mask and wafer distance from the source became more flexible. This was important for integration of the source with x-ray steppers for step-and-repeat wafer printing. Collimation of x-rays at wavelengths around 11 A was not straightforward que to the relatively poor reflectivity of materials in this region, and due to the constraints of the local and global divergence. A group at Lawrence Livermore National Laboratory (LLNL) extensively studied the design of such a collimator, both from an x-ray optics aspect and from a materials aspect. X-rays from the source were reflected by special coatings deposited on the highly polished cone or paraboloid interior. The materials used and their thickness were optimized to give highest x-ray reflectance corresponding to the angle of incidence at any point on the mirror surface.},
doi = {10.2172/1424640},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 09 00:00:00 EST 2018},
month = {Fri Feb 09 00:00:00 EST 2018}
}

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