{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23209"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23209","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Layer disordering and aluminum-gallium interchange in aluminum-gallium arsenide - gallium-arsenide quantum well heterostructures","abstract":"In the experiments described here, Al$\\sb{\\rm x}$Ga$\\sb{\\rm 1-x}$As-GaAs superlattice and quantum well heterostructure (QWH) crystals have been used as test vehicles to study Al-Ga interdiffusion. The data demonstrate that Al-Ga interchange is strongly influenced by the interdependence of the crystal surface-ambient interaction and the Fermi-level effect. We have investigated the crystal surface-ambient interaction by varying both the surface encapsulation condition (e.g., SiO$\\sb2$-cap, Si$\\sb3$N$\\sb4$-cap) and the anneal ambient (As-rich, Ga-rich). The Fermi-level effect has been examined for QWH crystals doped with either donor or acceptor impurities during crystal growth and annealed, and for crystals converted to n-type conductivity by high-temperature Si diffusion or by Si$\\sp+$ ion implantation and annealing.","abstract_html":"In the experiments described here, Al$\\sb{\\rm x}$Ga$\\sb{\\rm 1-x}$As-GaAs superlattice and quantum well heterostructure (QWH) crystals have been used as test vehicles to study Al-Ga interdiffusion. The data demonstrate that Al-Ga interchange is strongly influenced by the interdependence of the crystal surface-ambient interaction and the Fermi-level effect. We have investigated the crystal surface-ambient interaction by varying both the surface encapsulation condition (e.g., SiO$\\sb2$-cap, Si$\\sb3$N$\\sb4$-cap) and the anneal ambient (As-rich, Ga-rich). The Fermi-level effect has been examined for QWH crystals doped with either donor or acceptor impurities during crystal growth and annealed, and for crystals converted to n-type conductivity by high-temperature Si diffusion or by Si$\\sp+$ ion implantation and annealing.","abstract_has_math":true,"creators":["Guido, Louis Joseph"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Electrical and Computer Engineering","degree_department":null,"school":null,"contributors":["Holonyak, Nick, Jr."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T14:06:03Z","date_published":"2011-05-07T14:06:03Z","updated_at":"2026-07-22T22:25:21Z","subjects":["Engineering, Electronics and Electrical"],"languages":["eng"],"rights":["Copyright 1989 Guido, Louis Joseph"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8916256","(UMI)AAI8916256"],"render_values":[{"text":"AAI8916256","href":null,"code":true},{"text":"(UMI)AAI8916256","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23209","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Holonyak, Nick, Jr."]},{"key":"dc:creator","label":"Author","values":["Guido, Louis Joseph"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T14:06:03Z","10000-01-01","1989"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical and Computer 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, Electronics and Electrical"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1989 Guido, Louis Joseph"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8916256","(UMI)AAI8916256","http://hdl.handle.net/2142/23209"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["In the experiments described here, Al$\\sb{\\rm x}$Ga$\\sb{\\rm 1-x}$As-GaAs superlattice and quantum well heterostructure (QWH) crystals have been used as test vehicles to study Al-Ga interdiffusion. The data demonstrate that Al-Ga interchange is strongly influenced by the interdependence of the crystal surface-ambient interaction and the Fermi-level effect. We have investigated the crystal surface-ambient interaction by varying both the surface encapsulation condition (e.g., SiO$\\sb2$-cap, Si$\\sb3$N$\\sb4$-cap) and the anneal ambient (As-rich, Ga-rich). The Fermi-level effect has been examined for QWH crystals doped with either donor or acceptor impurities during crystal growth and annealed, and for crystals converted to n-type conductivity by high-temperature Si diffusion or by Si$\\sp+$ ion implantation and annealing.","The data show that Al-Ga interchange is enhanced for n-type samples annealed under As-rich conditions, and for p-type samples annealed under Ga-rich conditions. These trends suggest that acceptor native defects (V$\\sb{\\rm III}$) and donor native defects (I$\\sb{\\rm III}$, V$\\sb{\\rm As}$) are responsible for Al-Ga interdiffusion in n-type and p-type samples, respectively. By varying the anneal As$\\sb4$ over-pressure we have demonstrated that the degree of Al-Ga interchange does not increase monotonically for n-type samples as expected for a simple Column III vacancy controlled process. In addition, we show that the activation energy for Al-Ga interdiffusion (E$\\sb{\\rm Al-Ga}$) is reduced by $\\sb\\sim$2 eV for n-type samples as compared to nominally undoped samples. These results indicate that E$\\sb{\\rm Al-Ga}$ can be used to label the various Al-Ga interdiffusion regimes and, thereby, provide for more accurate identification of the native defect species involved in the interchange process. Furthermore, by employing three single-well QWH crystals that differ only in the location of the QW relative to the crystal surface, we demonstrate that the Al-Ga interchange mechanism is depth-dependent because of the re-equilibration of native defect concentrations at the crystal free surface. Finally, we report on Si$\\sp+$ ion implantation experiments that demonstrate enhanced Si$\\sp+$-IILD for very low implant doses, hence minimizing the effects of implant damage.","Made available in DSpace on 2011-05-07T14:06:03Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8916256.pdf: 2301924 bytes, checksum: a49eb1c268c04eb612ad8c0537a0751f (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:02:55Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:29:57-05:00 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":["Layer disordering and aluminum-gallium interchange in aluminum-gallium arsenide - gallium-arsenide quantum well heterostructures"]}]}],"canonical_facts":{"dc:contributor":["Holonyak, Nick, Jr."],"dc:creator":["Guido, Louis Joseph"],"dc:date":["2011-05-07T14:06:03Z","10000-01-01","1989"],"dc:description":["In the experiments described here, Al$\\sb{\\rm x}$Ga$\\sb{\\rm 1-x}$As-GaAs superlattice and quantum well heterostructure (QWH) crystals have been used as test vehicles to study Al-Ga interdiffusion. The data demonstrate that Al-Ga interchange is strongly influenced by the interdependence of the crystal surface-ambient interaction and the Fermi-level effect. We have investigated the crystal surface-ambient interaction by varying both the surface encapsulation condition (e.g., SiO$\\sb2$-cap, Si$\\sb3$N$\\sb4$-cap) and the anneal ambient (As-rich, Ga-rich). The Fermi-level effect has been examined for QWH crystals doped with either donor or acceptor impurities during crystal growth and annealed, and for crystals converted to n-type conductivity by high-temperature Si diffusion or by Si$\\sp+$ ion implantation and annealing.","The data show that Al-Ga interchange is enhanced for n-type samples annealed under As-rich conditions, and for p-type samples annealed under Ga-rich conditions. These trends suggest that acceptor native defects (V$\\sb{\\rm III}$) and donor native defects (I$\\sb{\\rm III}$, V$\\sb{\\rm As}$) are responsible for Al-Ga interdiffusion in n-type and p-type samples, respectively. By varying the anneal As$\\sb4$ over-pressure we have demonstrated that the degree of Al-Ga interchange does not increase monotonically for n-type samples as expected for a simple Column III vacancy controlled process. In addition, we show that the activation energy for Al-Ga interdiffusion (E$\\sb{\\rm Al-Ga}$) is reduced by $\\sb\\sim$2 eV for n-type samples as compared to nominally undoped samples. These results indicate that E$\\sb{\\rm Al-Ga}$ can be used to label the various Al-Ga interdiffusion regimes and, thereby, provide for more accurate identification of the native defect species involved in the interchange process. Furthermore, by employing three single-well QWH crystals that differ only in the location of the QW relative to the crystal surface, we demonstrate that the Al-Ga interchange mechanism is depth-dependent because of the re-equilibration of native defect concentrations at the crystal free surface. Finally, we report on Si$\\sp+$ ion implantation experiments that demonstrate enhanced Si$\\sp+$-IILD for very low implant doses, hence minimizing the effects of implant damage.","Made available in DSpace on 2011-05-07T14:06:03Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8916256.pdf: 2301924 bytes, checksum: a49eb1c268c04eb612ad8c0537a0751f (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:02:55Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:29:57-05:00 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":["AAI8916256","(UMI)AAI8916256","http://hdl.handle.net/2142/23209"],"dc:language":["eng"],"dc:rights":["Copyright 1989 Guido, Louis Joseph"],"dc:subject":["Engineering, Electronics and Electrical"],"dc:title":["Layer disordering and aluminum-gallium interchange in aluminum-gallium arsenide - gallium-arsenide quantum well heterostructures"],"dc:type":["text"],"thesis:degree_discipline":["Electrical and Computer Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:21Z"}