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Title: Energetic and thermal Sn interactions and their effect on EUVL source collector mirror lifetime at high temperatures.

Abstract

Exposure of collector mirrors facing the hot, dense pinch plasma in plasma-based EUV light sources remains one of the highest critical issues of source component lifetime and commercial feasibility of EUV lithography technology. Studies at Argonne have focused on understanding the underlying mechanisms that hinder collector mirror performance under Sn exposure and developing methods to mitigate them. Both Sn ion irradiation and thermal evaporation exposes candidate mirrors tested (i.e., Ru, Rh and Pd) in the experimental facility known as IMPACT (Interaction of Materials with charged Particles and Components Testing). Studies have led to an understanding of how Sn energetic ions compared to Sn thermal atoms affect three main surface properties of the collector mirror: (1) surface chemical state, (2) surface structure and (3) surface morphology. All these properties are crucial in understanding how collector mirrors will respond to Sn-based EUV source operation. This is primarily due to the correlation of how variation in these properties affects the reflectivity of photons in the EUV spectral range of interest (in-band 13.5-nm). This paper discusses the first property and its impact on 13.5-nm reflectivity. Investigation in the IMPACT experiment has focused on Sn thermal and energetic particle exposure on collector mirrors (Ru, Pdmore » and Rh) and its effect on mirror performance as a function of incident thermal flux, incident ion flux, incident angle and temperature. This is possible by a new state-of-the-art in-situ EUV reflectometry system that measures real time relative EUV reflectivity at 15-degree incidence and 13.5-nm during Sn exposure. These results are then compared to at-wavelength EUV reflectivity measurements using the newly upgraded NIST-SURF facility. Sn energetic ions at 1-keV and fluxes of about 10{sup 13} cm{sup -2}s{sup -1} are used in conjunction with a moderate flux Sn evaporative source delivering Sn fluences ranging from 10{sup 15}-10{sup 17} cm{sup -2}. The temperature of the mirror sample is locally varied between 25 and 200 C with the chemical state of the surface simultaneously monitored using X-ray photoelectron spectroscopy, and lowenergy ion scattering spectroscopy. Results demonstrate the balance between energetic and thermal Sn has on the total Sn surface fraction during exposure and its effect on the structural and reflective properties of the mirror surface.« less

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); Intel Corp.; Sematech
OSTI Identifier:
971460
Report Number(s):
ANL/MCS/CP-58850
TRN: US1001205
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: SPIE Advanced Lithography Conference; Feb. 25, 2007 - Mar. 2, 2007; San Jose, CA
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; CHARGED PARTICLES; CHEMICAL STATE; EVAPORATION; IRRADIATION; LIFETIME; LIGHT SOURCES; MIRRORS; MORPHOLOGY; PHOTONS; REFLECTIVITY; SCATTERING; SPECTROSCOPY; SURFACE PROPERTIES; TAIL IONS; TESTING; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Allain, J. P., Nieto, M., Hendricks, M., Hassanein, A., Tarrio, C., Grantham, S., Bakshi, V., NIST, and Sematech. Energetic and thermal Sn interactions and their effect on EUVL source collector mirror lifetime at high temperatures.. United States: N. p., 2007. Web. doi:10.1117/12.711270.
Allain, J. P., Nieto, M., Hendricks, M., Hassanein, A., Tarrio, C., Grantham, S., Bakshi, V., NIST, & Sematech. Energetic and thermal Sn interactions and their effect on EUVL source collector mirror lifetime at high temperatures.. United States. doi:10.1117/12.711270.
Allain, J. P., Nieto, M., Hendricks, M., Hassanein, A., Tarrio, C., Grantham, S., Bakshi, V., NIST, and Sematech. Mon . "Energetic and thermal Sn interactions and their effect on EUVL source collector mirror lifetime at high temperatures.". United States. doi:10.1117/12.711270.
@article{osti_971460,
title = {Energetic and thermal Sn interactions and their effect on EUVL source collector mirror lifetime at high temperatures.},
author = {Allain, J. P. and Nieto, M. and Hendricks, M. and Hassanein, A. and Tarrio, C. and Grantham, S. and Bakshi, V. and NIST and Sematech},
abstractNote = {Exposure of collector mirrors facing the hot, dense pinch plasma in plasma-based EUV light sources remains one of the highest critical issues of source component lifetime and commercial feasibility of EUV lithography technology. Studies at Argonne have focused on understanding the underlying mechanisms that hinder collector mirror performance under Sn exposure and developing methods to mitigate them. Both Sn ion irradiation and thermal evaporation exposes candidate mirrors tested (i.e., Ru, Rh and Pd) in the experimental facility known as IMPACT (Interaction of Materials with charged Particles and Components Testing). Studies have led to an understanding of how Sn energetic ions compared to Sn thermal atoms affect three main surface properties of the collector mirror: (1) surface chemical state, (2) surface structure and (3) surface morphology. All these properties are crucial in understanding how collector mirrors will respond to Sn-based EUV source operation. This is primarily due to the correlation of how variation in these properties affects the reflectivity of photons in the EUV spectral range of interest (in-band 13.5-nm). This paper discusses the first property and its impact on 13.5-nm reflectivity. Investigation in the IMPACT experiment has focused on Sn thermal and energetic particle exposure on collector mirrors (Ru, Pd and Rh) and its effect on mirror performance as a function of incident thermal flux, incident ion flux, incident angle and temperature. This is possible by a new state-of-the-art in-situ EUV reflectometry system that measures real time relative EUV reflectivity at 15-degree incidence and 13.5-nm during Sn exposure. These results are then compared to at-wavelength EUV reflectivity measurements using the newly upgraded NIST-SURF facility. Sn energetic ions at 1-keV and fluxes of about 10{sup 13} cm{sup -2}s{sup -1} are used in conjunction with a moderate flux Sn evaporative source delivering Sn fluences ranging from 10{sup 15}-10{sup 17} cm{sup -2}. The temperature of the mirror sample is locally varied between 25 and 200 C with the chemical state of the surface simultaneously monitored using X-ray photoelectron spectroscopy, and lowenergy ion scattering spectroscopy. Results demonstrate the balance between energetic and thermal Sn has on the total Sn surface fraction during exposure and its effect on the structural and reflective properties of the mirror surface.},
doi = {10.1117/12.711270},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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