Comprehensive analysis of current leakage at individual screw and mixed threading dislocations in freestanding GaN substrates

Comprehensive analysis of current leakage at individual screw and mixed threading dislocations in freestanding GaN substrates | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Comprehensive analysis of current leakage at individual screw and mixed threading dislocations in freestanding GaN substrates Takeaki Hamachi, Tetsuya Tohei, Yusuke Hayashi, Masayuki Imanishi, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2343828/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Feb, 2023 Read the published version in Scientific Reports → Version 1 posted 8 You are reading this latest preprint version Abstract The electrical characteristics of Schottky contacts on individual threading dislocations (TDs) with a screw-component in GaN substrates and the structures of these TDs were investigated to assess the effects of such defects on reverse leakage currents. Micrometer-scale platinum/GaN Schottky contacts were selectively fabricated on screw- and mixed-TD-related etch pits classified based on the pit size. Current-voltage ( I-V ) data acquired using conductive atomic force microscopy showed that very few of the screw TDs generated anomalously large reverse leakage currents. An analysis of the temperature dependence of the I-V characteristics established that the leakage current conduction mechanisms for the leaky screw TDs differed from those for the other screw and mixed TDs. Specifically, anomalous current leakage was generated by Poole-Frenkel emission and trap-assisted tunneling via distinctive trap states together with Fowler-Nordheim tunneling, with the mechanism changing according to variations in temperature and applied voltage. The leaky TDs were identified as Burgers vector b = 1 c closed-core screw TDs having a helical morphology similar to that of other screw TDs generating small leakage currents. Based on the results, we proposed that the atomic-scale modification of the dislocation core structure related to interactions with point defects via dislocation climbing caused different leakage characteristics of the TDs. Physical sciences/Materials science/Materials for devices Physical sciences/Materials science/Materials for devices/Electronic devices Full Text Additional Declarations No competing interests reported. Supplementary Files SciRep1HVPEleakagesupplementaryhamachi6sakai1submitted.docx Cite Share Download PDF Status: Published Journal Publication published 10 Feb, 2023 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Major revision 03 Jan, 2023 Reviews received at journal 23 Dec, 2022 Reviewers agreed at journal 13 Dec, 2022 Reviewers invited by journal 13 Dec, 2022 Editor assigned by journal 08 Dec, 2022 Editor invited by journal 08 Dec, 2022 Submission checks completed at journal 08 Dec, 2022 First submitted to journal 04 Dec, 2022 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2343828","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":158386715,"identity":"031f3879-9434-4567-a010-9024ac9a0750","order_by":0,"name":"Takeaki Hamachi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABK0lEQVRIie3RMUvDQBTA8RczuFy99WJK/AoXHoRCMgh+EUMgXVoQuktEiEsga/wcLo4XDsxy4JpSB0tXh0oXBykmomLxCnUTyX/KJfx4lzuArq6/2H7+/LgkAadgJs2Ste/Mr69cR4hAt+jH3EqMXQk79mwSSM7FO4FNoovXEFvFSCJWZXo4vR0ApXLBX0ACvRIwOdOQWSIHSzX0PBWm9lgxsIoYw6whTJ0CFhryUF5MrzM/8ERLUtbORdFbS4AaAIluYxHYvbUZYD7/IPfVqnxtphxtJfGeTciJx9nnFDHCiDSEbyGWUqZbkBhZPb/0G0Kaw5hgH4bEVWGi+5eDKjPaq3TzPCpn4/TcobS6sZ7Ad5xK3qHmxH5Evj0YKe4gNjMXvyZdXV1d/7A3DTZkNLHxhiAAAAAASUVORK5CYII=","orcid":"","institution":"Osaka University","correspondingAuthor":true,"prefix":"","firstName":"Takeaki","middleName":"","lastName":"Hamachi","suffix":""},{"id":158386716,"identity":"0984dcd8-f218-45c4-b562-a69278a7f48a","order_by":1,"name":"Tetsuya Tohei","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Tetsuya","middleName":"","lastName":"Tohei","suffix":""},{"id":158386717,"identity":"8933f4c9-da35-4adc-8b6d-bc2a7ef95d65","order_by":2,"name":"Yusuke Hayashi","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Yusuke","middleName":"","lastName":"Hayashi","suffix":""},{"id":158386718,"identity":"b20ec195-82da-4b43-91ec-ed7d2125fad7","order_by":3,"name":"Masayuki Imanishi","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Masayuki","middleName":"","lastName":"Imanishi","suffix":""},{"id":158386719,"identity":"c462358e-b3cb-4cc9-a0ea-ac279aa6bd4d","order_by":4,"name":"Shigeyoshi Usami","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Shigeyoshi","middleName":"","lastName":"Usami","suffix":""},{"id":158386720,"identity":"0a4d40a3-f89d-41ff-930d-086da7f5ef7d","order_by":5,"name":"Yusuke Mori","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Yusuke","middleName":"","lastName":"Mori","suffix":""},{"id":158386721,"identity":"2d15575e-0833-4f18-9ac0-248ae2380446","order_by":6,"name":"Akira Sakai","email":"","orcid":"","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Akira","middleName":"","lastName":"Sakai","suffix":""}],"badges":[],"createdAt":"2022-12-04 22:59:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2343828/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2343828/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-023-29458-3","type":"published","date":"2023-02-10T18:44:56+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":44719134,"identity":"74fe9a3a-5b2b-4549-ac31-bea7ee2e5078","added_by":"auto","created_at":"2023-10-16 18:53:21","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2050943,"visible":true,"origin":"","legend":"","description":"","filename":"SciRep1HVPEleakagemanuscripthamachi8sakai6submitted.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2343828/v1_covered_f3c98ebe-e6e2-4e35-8ea2-1901d6212ebf.pdf"},{"id":30275947,"identity":"c6ed049d-c28a-44b5-ac69-f76df9d51b3e","added_by":"auto","created_at":"2022-12-13 17:32:09","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":1427065,"visible":true,"origin":"","legend":"","description":"","filename":"SciRep1HVPEleakagesupplementaryhamachi6sakai1submitted.docx","url":"https://assets-eu.researchsquare.com/files/rs-2343828/v1/fa4f05dcd7b91105b95a62eb.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comprehensive analysis of current leakage at individual screw and mixed threading dislocations in freestanding GaN substrates","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-2343828/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2343828/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe electrical characteristics of Schottky contacts on individual threading dislocations (TDs) with a screw-component in GaN substrates and the structures of these TDs were investigated to assess the effects of such defects on reverse leakage currents. Micrometer-scale platinum/GaN Schottky contacts were selectively fabricated on screw- and mixed-TD-related etch pits classified based on the pit size. Current-voltage (\u003cem\u003eI-V\u003c/em\u003e) data acquired using conductive atomic force microscopy showed that very few of the screw TDs generated anomalously large reverse leakage currents. An analysis of the temperature dependence of the \u003cem\u003eI-V\u003c/em\u003e characteristics established that the leakage current conduction mechanisms for the leaky screw TDs differed from those for the other screw and mixed TDs. Specifically, anomalous current leakage was generated by Poole-Frenkel emission and trap-assisted tunneling via distinctive trap states together with Fowler-Nordheim tunneling, with the mechanism changing according to variations in temperature and applied voltage. The leaky TDs were identified as Burgers vector \u003cb\u003eb\u003c/b\u003e\u0026thinsp;=\u0026thinsp;1\u003cspan type=\"BoldItalic\" class=\"BoldItalic\" name=\"Emphasis\"\u003ec\u003c/span\u003e closed-core screw TDs having a helical morphology similar to that of other screw TDs generating small leakage currents. Based on the results, we proposed that the atomic-scale modification of the dislocation core structure related to interactions with point defects via dislocation climbing caused different leakage characteristics of the TDs.\u003c/p\u003e","manuscriptTitle":"Comprehensive analysis of current leakage at individual screw and mixed threading dislocations in freestanding GaN substrates","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-12-13 17:32:04","doi":"10.21203/rs.3.rs-2343828/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-01-03T06:05:51+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-12-23T09:09:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"b441b10e-3472-415a-a647-ef770fa8a602","date":"2022-12-14T00:28:15+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-12-13T08:12:29+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-12-08T06:14:34+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2022-12-08T06:09:35+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-12-08T05:32:27+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2022-12-04T22:45:45+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8eb5c0e7-1094-41fc-b539-7c193d3ff3a2","owner":[],"postedDate":"December 13th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":17547009,"name":"Physical sciences/Materials science/Materials for devices"},{"id":17547010,"name":"Physical sciences/Materials science/Materials for devices/Electronic devices"}],"tags":[],"updatedAt":"2023-10-16T18:49:19+00:00","versionOfRecord":{"articleIdentity":"rs-2343828","link":"https://doi.org/10.1038/s41598-023-29458-3","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2023-02-10 18:44:56","publishedOnDateReadable":"February 10th, 2023"},"versionCreatedAt":"2022-12-13 17:32:04","video":"","vorDoi":"10.1038/s41598-023-29458-3","vorDoiUrl":"https://doi.org/10.1038/s41598-023-29458-3","workflowStages":[]},"version":"v1","identity":"rs-2343828","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2343828","identity":"rs-2343828","version":["v1"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}