{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,6]],"date-time":"2025-12-06T17:08:34Z","timestamp":1765040914020,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,19]],"date-time":"2019-02-19T00:00:00Z","timestamp":1550534400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER funds","award":["COMPETE 2020 Programme"],"award-info":[{"award-number":["COMPETE 2020 Programme"]}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-007688","SFRH\/BPD\/99136\/2013"],"award-info":[{"award-number":["POCI-01-0145-FEDER-007688","SFRH\/BPD\/99136\/2013"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["700395"],"award-info":[{"award-number":["700395"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["SFB 595"],"award-info":[{"award-number":["SFB 595"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Multi-level resistive switching characteristics of a Cu2O\/Al2O3 bilayer device are presented. An oxidation state gradient in copper oxide induced by the fabrication process was found to play a dominant role in defining the multiple resistance states. The highly conductive grain boundaries of the copper oxide\u2014an unusual property for an oxide semiconductor\u2014are discussed for the first time regarding their role in the resistive switching mechanism.<\/jats:p>","DOI":"10.3390\/nano9020289","type":"journal-article","created":{"date-parts":[[2019,2,20]],"date-time":"2019-02-20T03:05:52Z","timestamp":1550631952000},"page":"289","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Multi-Level Cell Properties of a Bilayer Cu2O\/Al2O3 Resistive Switching Device"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2764-3124","authenticated-orcid":false,"given":"Jonas","family":"Deuermeier","sequence":"first","affiliation":[{"name":"i3N\/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP\/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal"}]},{"given":"Asal","family":"Kiazadeh","sequence":"additional","affiliation":[{"name":"i3N\/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP\/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7463-1495","authenticated-orcid":false,"given":"Andreas","family":"Klein","sequence":"additional","affiliation":[{"name":"Department of Materials and Earth Sciences, Technische Universit\u00e4t Darmstadt, Otto-Berndt-Stra\u00dfe 3, D-64287 Darmstadt, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1997-7669","authenticated-orcid":false,"given":"Rodrigo","family":"Martins","sequence":"additional","affiliation":[{"name":"i3N\/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP\/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal"}]},{"given":"Elvira","family":"Fortunato","sequence":"additional","affiliation":[{"name":"i3N\/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP\/UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1038\/nnano.2008.160","article-title":"Memristive switching mechanism for metal\/oxide\/metal nanodevices","volume":"3","author":"Yang","year":"2008","journal-title":"Nat. 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