{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/105822"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/105822","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Reduced density hydrogenated silicon through reactive dc magnetron sputtering with secondary rf plasma discharge for EUV multilayer mirror application","abstract":"Made available in DSpace on 2019-11-26T20:49:30Z (GMT). No. of bitstreams: 2 UHLIG-THESIS-2019.pdf: 3040065 bytes, checksum: 4444cd75305422a711eb398f1ec5e75c (MD5) LICENSE.txt: 4206 bytes, checksum: 5a9d596ce58190a77714e399a794eb23 (MD5) Previous issue date: 2019-07-18","abstract_html":"Made available in DSpace on 2019-11-26T20:49:30Z (GMT). No. of bitstreams: 2 UHLIG-THESIS-2019.pdf: 3040065 bytes, checksum: 4444cd75305422a711eb398f1ec5e75c (MD5) LICENSE.txt: 4206 bytes, checksum: 5a9d596ce58190a77714e399a794eb23 (MD5) Previous issue date: 2019-07-18","abstract_has_math":false,"creators":["Uhlig, Jan Peter"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Nuclear, Plasma, Radiolgc Engr","degree_department":null,"school":null,"contributors":["Ruzic, David N","Andruczyk, Daniel"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-11-26T20:49:30Z","date_published":"2019-11-26T20:49:30Z","updated_at":"2026-07-22T22:24:45Z","subjects":["Reduced Density Si","Multilayer Mirror","EUV"],"languages":["en"],"rights":["Copyright 2019 Jan Uhlig"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/105822","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Ruzic, David N","Andruczyk, Daniel"]},{"key":"dc:creator","label":"Author","values":["Uhlig, Jan Peter"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-11-26T20:49:30Z","2021-11-27T10:15:30Z","2019-07-18","2019-08"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Nuclear, Plasma, Radiolgc Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Reduced Density Si","Multilayer Mirror","EUV"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2019 Jan Uhlig"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/105822"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Made available in DSpace on 2019-11-26T20:49:30Z (GMT). No. of bitstreams: 2 UHLIG-THESIS-2019.pdf: 3040065 bytes, checksum: 4444cd75305422a711eb398f1ec5e75c (MD5) LICENSE.txt: 4206 bytes, checksum: 5a9d596ce58190a77714e399a794eb23 (MD5) Previous issue date: 2019-07-18","U of I Only Restriction Lifted for Item 112967 on 2021-11-27T10:15:30Z.","In Extreme Ultra-violet Lithography applications Si/Mo Multi-Layer Mirrors are used to collect, transmit and focus EUV light. While current MLMs have reached the practical limit achievable with current materials, the per mirror efficiency is still suboptimal, especially in a projection lithography system with a multitude of these mirrors. A method of improvement then, without significantly modifying the mirror itself or the process for manufacture of the mirrors, is to replace the Si spacer layer found in EUV mirrors, with a reduced density Si layer. Theory predicts that such a modification, if done without introducing contaminants that absorb EUV themselves, can marginally increase the per mirror efficiency. When this per mirror marginal improvement is then applied to all mirrors in a lithography system the end result comes out to be a two-fold or more increase in efficiency of the system. Investigated in this work then is a method for replacing the Si film with a reduced density Si:H film, through the modification of the standard DCMS deposition process through reactive DCMS with hydrogen, along with a secondary RF plasma to aide in radical generation. The eventual goal is to produce both hydrogenated and non-hydrogenated MLMs to the same specifications, which can then be tested for EUV reflectivity, proving the initial theory. In the process for producing the low density hydrogenated Si film discussed the main issue that presented itself was the formation of H2 gas blisters in the film, likely at subsurface interfaces, leading to structures that project beyond the surface of the film. Methods for the avoidance of these blisters are discussed and applied, leading, among others, to Si:H films with a density of 1.73 g/cm3, with lesser numbers and smaller blisters than previously observed. Finally, successful attempts are also made at producing multilayers at the appropriate size for EUV reflectivity, that is with a bilayer thickness of 6.9 nm.","Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-08-01","The student, Jan Uhlig, accepted the attached license on 2019-07-15 at 14:47.","The student, Jan Uhlig, submitted this Thesis for approval on 2019-07-15 at 15:03.","This Thesis was approved for publication on 2019-07-18 at 11:34.","DSpace SAF Submission Ingestion Package generated from Vireo submission #14322 on 2019-11-26 at 13:05:56","Embargo set by: Seth Robbins for item 112967 Lift date: 2021-11-26T20:49:41Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Reduced density hydrogenated silicon through reactive dc magnetron sputtering with secondary rf plasma discharge for EUV multilayer mirror application"]}]}],"canonical_facts":{"dc:contributor":["Ruzic, David N","Andruczyk, Daniel"],"dc:creator":["Uhlig, Jan Peter"],"dc:date":["2019-11-26T20:49:30Z","2021-11-27T10:15:30Z","2019-07-18","2019-08"],"dc:description":["Made available in DSpace on 2019-11-26T20:49:30Z (GMT). No. of bitstreams: 2 UHLIG-THESIS-2019.pdf: 3040065 bytes, checksum: 4444cd75305422a711eb398f1ec5e75c (MD5) LICENSE.txt: 4206 bytes, checksum: 5a9d596ce58190a77714e399a794eb23 (MD5) Previous issue date: 2019-07-18","U of I Only Restriction Lifted for Item 112967 on 2021-11-27T10:15:30Z.","In Extreme Ultra-violet Lithography applications Si/Mo Multi-Layer Mirrors are used to collect, transmit and focus EUV light. While current MLMs have reached the practical limit achievable with current materials, the per mirror efficiency is still suboptimal, especially in a projection lithography system with a multitude of these mirrors. A method of improvement then, without significantly modifying the mirror itself or the process for manufacture of the mirrors, is to replace the Si spacer layer found in EUV mirrors, with a reduced density Si layer. Theory predicts that such a modification, if done without introducing contaminants that absorb EUV themselves, can marginally increase the per mirror efficiency. When this per mirror marginal improvement is then applied to all mirrors in a lithography system the end result comes out to be a two-fold or more increase in efficiency of the system. Investigated in this work then is a method for replacing the Si film with a reduced density Si:H film, through the modification of the standard DCMS deposition process through reactive DCMS with hydrogen, along with a secondary RF plasma to aide in radical generation. The eventual goal is to produce both hydrogenated and non-hydrogenated MLMs to the same specifications, which can then be tested for EUV reflectivity, proving the initial theory. In the process for producing the low density hydrogenated Si film discussed the main issue that presented itself was the formation of H2 gas blisters in the film, likely at subsurface interfaces, leading to structures that project beyond the surface of the film. Methods for the avoidance of these blisters are discussed and applied, leading, among others, to Si:H films with a density of 1.73 g/cm3, with lesser numbers and smaller blisters than previously observed. Finally, successful attempts are also made at producing multilayers at the appropriate size for EUV reflectivity, that is with a bilayer thickness of 6.9 nm.","Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-08-01","The student, Jan Uhlig, accepted the attached license on 2019-07-15 at 14:47.","The student, Jan Uhlig, submitted this Thesis for approval on 2019-07-15 at 15:03.","This Thesis was approved for publication on 2019-07-18 at 11:34.","DSpace SAF Submission Ingestion Package generated from Vireo submission #14322 on 2019-11-26 at 13:05:56","Embargo set by: Seth Robbins for item 112967 Lift date: 2021-11-26T20:49:41Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/105822"],"dc:language":["en"],"dc:rights":["Copyright 2019 Jan Uhlig"],"dc:subject":["Reduced Density Si","Multilayer Mirror","EUV"],"dc:title":["Reduced density hydrogenated silicon through reactive dc magnetron sputtering with secondary rf plasma discharge for EUV multilayer mirror application"],"dc:type":["text"],"thesis:degree_discipline":["Nuclear, Plasma, Radiolgc Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:45Z"}