{"id":{"repo_id":"brunel","oai_identifier":"oai:bura.brunel.ac.uk:2438/10450"},"canonical_url":"https://search.dev.ndltd.org/etd/brunel/oai:bura.brunel.ac.uk:2438/10450","repository":{"repo_id":"brunel","name":"University of Brunel","base_url":"https://bura.brunel.ac.uk/oai/request"},"display":{"title":"Long and short term effects of X-rays on charge coupled devices","abstract":"EEV buried channel charge coupled devices (BC CDs) with technological variations have been studied with respect to their response to 70kVp X-rays. Process variations considered are the conventional BCCD, scintillator coated BCCDs ( (Gadox(Eu) and Csl(Tl)) and the inversion mode device. The work was made necessary by the use of these CCDs for dental X-ray imaging. Effects investigated include changes in device operating voltages and dark current. The dark current buildup has been characterised in terms of a prompt component seen immediately following irradiation, and a time dependent component which occurs gradually. A major part of this work was the determination of the location and concentration of the energy states responsible for this dark current buildup. Also a novel aspect of the work was the derivation of an expression describing the time dependent component as a function of time and temperature. Effects associated with the bias dependence of the BCCD have also been considered, with particular regard to the effect of a negative substrate bias, and the theoretical explanation has been developed. The findings of this work have demonstrated the suitability of these devices for the commercial application of imaging x-rays for dentistry.","abstract_html":"EEV buried channel charge coupled devices (BC CDs) with technological variations have been studied with respect to their response to 70kVp X-rays. Process variations considered are the conventional BCCD, scintillator coated BCCDs ( (Gadox(Eu) and Csl(Tl)) and the inversion mode device. The work was made necessary by the use of these CCDs for dental X-ray imaging. Effects investigated include changes in device operating voltages and dark current. The dark current buildup has been characterised in terms of a prompt component seen immediately following irradiation, and a time dependent component which occurs gradually. A major part of this work was the determination of the location and concentration of the energy states responsible for this dark current buildup. Also a novel aspect of the work was the derivation of an expression describing the time dependent component as a function of time and temperature. Effects associated with the bias dependence of the BCCD have also been considered, with particular regard to the effect of a negative substrate bias, and the theoretical explanation has been developed. The findings of this work have demonstrated the suitability of these devices for the commercial application of imaging x-rays for dentistry.","abstract_has_math":false,"creators":["Tudge, Mark Vernon"],"institution":"Brunel University London","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1996,"date_issued":"1996","date_published":"1996","updated_at":"2026-07-24T01:23:31Z","subjects":["Biomedical radiography","Optoelectronics","Solid state physics","Semiconductor devices","Photocurrents"],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Tudge, Mark Vernon"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-03-19T15:32:52Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-03-19T15:32:52Z"]},{"key":"dc:date.issued","label":"Date","values":["1996"]},{"key":"dc:publisher","label":"Institution","values":["Brunel University London"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biomedical radiography","Optoelectronics","Solid state physics","Semiconductor devices","Photocurrents"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://bura.brunel.ac.uk/bitstream/2438/10557/1/FulltextThesis.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London"]},{"key":"dc:description.abstract","label":"Abstract","values":["EEV buried channel charge coupled devices (BC CDs) with technological variations have been studied with respect to their response to 70kVp X-rays. Process variations considered are the conventional BCCD, scintillator coated BCCDs ( (Gadox(Eu) and Csl(Tl)) and the inversion mode device. The work was made necessary by the use of these CCDs for dental X-ray imaging. Effects investigated include changes in device operating voltages and dark current. The dark current buildup has been characterised in terms of a prompt component seen immediately following irradiation, and a time dependent component which occurs gradually. A major part of this work was the determination of the location and concentration of the energy states responsible for this dark current buildup. Also a novel aspect of the work was the derivation of an expression describing the time dependent component as a function of time and temperature. Effects associated with the bias dependence of the BCCD have also been considered, with particular regard to the effect of a negative substrate bias, and the theoretical explanation has been developed. The findings of this work have demonstrated the suitability of these devices for the commercial application of imaging x-rays for dentistry."]},{"key":"dc:title","label":"Title","values":["Long and short term effects of X-rays on charge coupled devices"]}]}],"canonical_facts":{"dc:creator":["Tudge, Mark Vernon"],"dc:date.accessioned":["2015-03-19T15:32:52Z"],"dc:date.available":["2015-03-19T15:32:52Z"],"dc:date.issued":["1996"],"dc:description":["This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London"],"dc:description.abstract":["EEV buried channel charge coupled devices (BC CDs) with technological variations have been studied with respect to their response to 70kVp X-rays. Process variations considered are the conventional BCCD, scintillator coated BCCDs ( (Gadox(Eu) and Csl(Tl)) and the inversion mode device. The work was made necessary by the use of these CCDs for dental X-ray imaging. Effects investigated include changes in device operating voltages and dark current. The dark current buildup has been characterised in terms of a prompt component seen immediately following irradiation, and a time dependent component which occurs gradually. A major part of this work was the determination of the location and concentration of the energy states responsible for this dark current buildup. Also a novel aspect of the work was the derivation of an expression describing the time dependent component as a function of time and temperature. Effects associated with the bias dependence of the BCCD have also been considered, with particular regard to the effect of a negative substrate bias, and the theoretical explanation has been developed. The findings of this work have demonstrated the suitability of these devices for the commercial application of imaging x-rays for dentistry."],"dc:identifier.uri":["http://bura.brunel.ac.uk/bitstream/2438/10557/1/FulltextThesis.pdf"],"dc:language.iso":["en"],"dc:publisher":["Brunel University London"],"dc:subject":["Biomedical radiography","Optoelectronics","Solid state physics","Semiconductor devices","Photocurrents"],"dc:title":["Long and short term effects of X-rays on charge coupled devices"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T01:23:31Z"}