{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/21451"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/21451","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Sol-gel processing, perovskite phase development and properties of relaxor-based thin layer ferroelectrics","abstract":"This thesis reports on the preparation and properties of thin layer ceramics in the Pb ((Zn$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PZNT) and Pb ((Mg$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PMNT) systems for capacitor and ferroelectric applications. Sol-gel methods were used to prepare thin layers by spin-casting partially hydrolysed alkoxide-based solutions on platinized Si substrates. As-deposited layers were amorphous, and formed a nonferroelectric pyrochlore phase or a ferroelectric perovskite phase, depending on the processing route. Since the perovskite structure is required for ferroelectric properties, the phase development and processing methods for perovskite formation were investigated in detail for thin layers and powders.","abstract_html":"This thesis reports on the preparation and properties of thin layer ceramics in the Pb ((Zn$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PZNT) and Pb ((Mg$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PMNT) systems for capacitor and ferroelectric applications. Sol-gel methods were used to prepare thin layers by spin-casting partially hydrolysed alkoxide-based solutions on platinized Si substrates. As-deposited layers were amorphous, and formed a nonferroelectric pyrochlore phase or a ferroelectric perovskite phase, depending on the processing route. Since the perovskite structure is required for ferroelectric properties, the phase development and processing methods for perovskite formation were investigated in detail for thin layers and powders.","abstract_has_math":true,"creators":["Francis, Lorraine Falter"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Materials Engineering","degree_department":null,"school":null,"contributors":["Payne, David A."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:09:02Z","date_published":"2011-05-07T13:09:02Z","updated_at":"2026-07-22T22:25:18Z","subjects":["Engineering, Materials Science"],"languages":["eng"],"rights":["Copyright 1991 Francis, Lorraine Falter"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9124413","(UMI)AAI9124413"],"render_values":[{"text":"AAI9124413","href":null,"code":true},{"text":"(UMI)AAI9124413","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/21451","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Payne, David A."]},{"key":"dc:creator","label":"Author","values":["Francis, Lorraine Falter"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T13:09:02Z","10000-01-01","1991"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Materials Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"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":["Engineering, Materials Science"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1991 Francis, Lorraine Falter"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9124413","(UMI)AAI9124413","http://hdl.handle.net/2142/21451"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This thesis reports on the preparation and properties of thin layer ceramics in the Pb ((Zn$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PZNT) and Pb ((Mg$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PMNT) systems for capacitor and ferroelectric applications. Sol-gel methods were used to prepare thin layers by spin-casting partially hydrolysed alkoxide-based solutions on platinized Si substrates. As-deposited layers were amorphous, and formed a nonferroelectric pyrochlore phase or a ferroelectric perovskite phase, depending on the processing route. Since the perovskite structure is required for ferroelectric properties, the phase development and processing methods for perovskite formation were investigated in detail for thin layers and powders.","Crystalline phase development in sol-gel derived powders and thin layers was studied by thermal analysis and X-ray diffraction. All compositions crystallized first into a cubic pyrochlore phase. Pb$\\sb2$ ((M$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) $\\sb2$O$\\sb6$ and at higher temperatures, formed the perovskite phase Pb ((M$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (M is Mg or Zn). For powders, the gelation conditions affected the rate of perovskite formation. The unit cell parameters and formation temperatures for the pyrochlore and perovskite phases were found to depend on composition. The evolution of structure with heat-treatment was explained in terms of a general model of thermally activated processes.","With optimized processing, thin layers in the entire PMNT system could be prepared in the perovskite structure. The most effective processing method was spin-casting, followed by rapid heat-treatment to a temperature sufficiently high for the perovskite structure to crystallize, without the formation of the pyrochlore phase. Solution additives (HNO$\\sb3$, NH$\\sb4$OH and benzoic acid) also affected perovskite content and microstructure. Dielectric and ferroelectric properties of thin layers were determined and related to composition, microstructure and phase content. PMN rich thin layers had high dielectric constants (K) and low remanent polarization (P$\\sb{\\rm r}$) values (e.g., 90 PMNT: K $\\sim$ 2200, tan $\\partial$ $<$ 0.03; P$\\sb{\\rm r}$ = 3 $\\mu$C/cm$\\sp2$, E$\\sb{\\rm c}$ = 18 kV/cm), whereas PT rich thin layers had relatively high P$\\sb{\\rm r}$ values with lower dielectric constants (e.g., 30PMNT: K $\\sim$ 500, tan $\\partial$ $<$ 0.03, P$\\sb{\\rm r}$ $\\sim$ 12 $\\mu$C/cm$\\sp2$, E$\\sb{\\rm c}$ = 40 kV/cm). Thin layers in the PMNT system have potential for thin layer capacitor and ferroelectric memory applications which can now be integrated directly onto semiconductors by sol-gel methods.","Made available in DSpace on 2011-05-07T13:09:02Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9124413.pdf: 10058009 bytes, checksum: 685a97f742d3a472e9357b4d6d651b1b (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:50:52Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:23:17-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Sol-gel processing, perovskite phase development and properties of relaxor-based thin layer ferroelectrics"]}]}],"canonical_facts":{"dc:contributor":["Payne, David A."],"dc:creator":["Francis, Lorraine Falter"],"dc:date":["2011-05-07T13:09:02Z","10000-01-01","1991"],"dc:description":["This thesis reports on the preparation and properties of thin layer ceramics in the Pb ((Zn$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PZNT) and Pb ((Mg$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (PMNT) systems for capacitor and ferroelectric applications. Sol-gel methods were used to prepare thin layers by spin-casting partially hydrolysed alkoxide-based solutions on platinized Si substrates. As-deposited layers were amorphous, and formed a nonferroelectric pyrochlore phase or a ferroelectric perovskite phase, depending on the processing route. Since the perovskite structure is required for ferroelectric properties, the phase development and processing methods for perovskite formation were investigated in detail for thin layers and powders.","Crystalline phase development in sol-gel derived powders and thin layers was studied by thermal analysis and X-ray diffraction. All compositions crystallized first into a cubic pyrochlore phase. Pb$\\sb2$ ((M$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) $\\sb2$O$\\sb6$ and at higher temperatures, formed the perovskite phase Pb ((M$\\sb{1/3}$Nb$\\sb{2/3})\\sb{\\rm 1-x}$Ti$\\sb{\\rm x}$) O$\\sb3$ (M is Mg or Zn). For powders, the gelation conditions affected the rate of perovskite formation. The unit cell parameters and formation temperatures for the pyrochlore and perovskite phases were found to depend on composition. The evolution of structure with heat-treatment was explained in terms of a general model of thermally activated processes.","With optimized processing, thin layers in the entire PMNT system could be prepared in the perovskite structure. The most effective processing method was spin-casting, followed by rapid heat-treatment to a temperature sufficiently high for the perovskite structure to crystallize, without the formation of the pyrochlore phase. Solution additives (HNO$\\sb3$, NH$\\sb4$OH and benzoic acid) also affected perovskite content and microstructure. Dielectric and ferroelectric properties of thin layers were determined and related to composition, microstructure and phase content. PMN rich thin layers had high dielectric constants (K) and low remanent polarization (P$\\sb{\\rm r}$) values (e.g., 90 PMNT: K $\\sim$ 2200, tan $\\partial$ $<$ 0.03; P$\\sb{\\rm r}$ = 3 $\\mu$C/cm$\\sp2$, E$\\sb{\\rm c}$ = 18 kV/cm), whereas PT rich thin layers had relatively high P$\\sb{\\rm r}$ values with lower dielectric constants (e.g., 30PMNT: K $\\sim$ 500, tan $\\partial$ $<$ 0.03, P$\\sb{\\rm r}$ $\\sim$ 12 $\\mu$C/cm$\\sp2$, E$\\sb{\\rm c}$ = 40 kV/cm). Thin layers in the PMNT system have potential for thin layer capacitor and ferroelectric memory applications which can now be integrated directly onto semiconductors by sol-gel methods.","Made available in DSpace on 2011-05-07T13:09:02Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9124413.pdf: 10058009 bytes, checksum: 685a97f742d3a472e9357b4d6d651b1b (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:50:52Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:23:17-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9124413","(UMI)AAI9124413","http://hdl.handle.net/2142/21451"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Francis, Lorraine Falter"],"dc:subject":["Engineering, Materials Science"],"dc:title":["Sol-gel processing, perovskite phase development and properties of relaxor-based thin layer ferroelectrics"],"dc:type":["text"],"thesis:degree_discipline":["Materials Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:18Z"}