Automated Spray Deposition of Liquid Metal: Process Assessment Towards Scalability and Reliability for Stretchable Electronics

Automated Spray Deposition of Liquid Metal: Process Assessment Towards Scalability and Reliability for Stretchable Electronics | 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 Research Article Automated Spray Deposition of Liquid Metal: Process Assessment Towards Scalability and Reliability for Stretchable Electronics Maximilian Krack, Rathul Nengminza Sangma, Lennert Purnal, Parth Vinayakrao Sewlikar, and 11 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5810378/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Oct, 2025 Read the published version in Scientific Reports → Version 1 posted You are reading this latest preprint version Abstract Liquid metal stretchable electronics (LMSE) offer remarkable stretchability, softness, and self-healing properties, making them ideal for smart wearables and soft robotics. A key fabrication method involves spray deposition of LM into patterned structures. However, reliance on manual airbrush techniques has hindered understanding of how spray parameters impact LM deposition, limiting scalability and reliability. This work addresses these challenges by using an innovative automated spray coater (ASC), which provides precise control over deposition. For the first time, the ASC enables a systematic investigation of how spray parameters—such as flow rate, pressure, and spraying distance—affect LMSE properties like reliability, uniformity, and hysteresis. We find that rougher coatings improve yield (nearly 100\%), but compromise long-term reliability. Additionally, finer linewidth patterns (0.25 mm) fail earlier in cyclic testing and show reduced self-healing capabilities compared to wider lines ($>0.5 mm$). The ASC's capabilities are demonstrated through the fabrication of LMSE devices, including a 16-LED array and a large wearable strain sensor (70 × 150 mm) for human motion capture. This work provides crucial insights into LM deposition and highlights relevant applications, advancing the development of scalable and reliable stretchable electronics. Materials Engineering Liquid Metal Stretchable Electronics Spray Deposition Stencil Printing Strain Sensor Full Text Additional Declarations The authors declare no competing interests. Supplementary Files Supporting.pdf Cycletester.mp4 Cycletester.mp4 Cite Share Download PDF Status: Published Journal Publication published 14 Oct, 2025 Read the published version in Scientific Reports → Version 1 posted 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-5810378","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":400878730,"identity":"eaf15581-1fea-40dc-8381-92d366f18e89","order_by":0,"name":"Maximilian Krack","email":"","orcid":"https://orcid.org/0000-0002-8222-4483","institution":"Hasselt University","correspondingAuthor":false,"prefix":"","firstName":"Maximilian","middleName":"","lastName":"Krack","suffix":""},{"id":400879010,"identity":"f58e7e26-8163-4086-bad8-63218d5a7625","order_by":1,"name":"Rathul Nengminza Sangma","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Rathul","middleName":"Nengminza","lastName":"Sangma","suffix":""},{"id":400879011,"identity":"d02e7c3d-c1c1-48b2-86d2-eaafb881fcd4","order_by":2,"name":"Lennert Purnal","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Lennert","middleName":"","lastName":"Purnal","suffix":""},{"id":400879012,"identity":"8f17be2d-aed2-4494-97b9-6dd31c040233","order_by":3,"name":"Parth Vinayakrao Sewlikar","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Parth","middleName":"Vinayakrao","lastName":"Sewlikar","suffix":""},{"id":400879013,"identity":"edf6dbfe-1fc6-4b16-9afa-67d6a5611f51","order_by":4,"name":"Dieter Reenars","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Dieter","middleName":"","lastName":"Reenars","suffix":""},{"id":400879014,"identity":"c94f24bd-6d6a-47f8-aafa-9313e41c9429","order_by":5,"name":"Fatemeh Sahraeeazartamar","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Fatemeh","middleName":"","lastName":"Sahraeeazartamar","suffix":""},{"id":400879015,"identity":"31dc5df1-7d87-4a09-8359-ae5de4a9a63d","order_by":6,"name":"Joost Brancart","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Joost","middleName":"","lastName":"Brancart","suffix":""},{"id":400879016,"identity":"e3fc17ef-940f-45ca-a722-d14bf814da81","order_by":7,"name":"Guy Van Assche","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Guy","middleName":"Van","lastName":"Assche","suffix":""},{"id":400879017,"identity":"5741a2f8-a7cf-4783-b6ac-f2050f365b0d","order_by":8,"name":"Iris De Graeve","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Iris","middleName":"","lastName":"De Graeve","suffix":""},{"id":400879018,"identity":"0a2d755a-343e-49a3-be6e-b58b505d3e3f","order_by":9,"name":"Tom Hauffman","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Tom","middleName":"","lastName":"Hauffman","suffix":""},{"id":400879019,"identity":"7a477e6a-b67c-48ad-b23e-bac545eaeb0d","order_by":10,"name":"Michael Daenen","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Michael","middleName":"","lastName":"Daenen","suffix":""},{"id":400879020,"identity":"f43a3f10-6838-44ff-8ee6-da763e00876b","order_by":11,"name":"Seppe Terryn","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Seppe","middleName":"","lastName":"Terryn","suffix":""},{"id":400879021,"identity":"628b794b-3af5-4308-9ec1-3d8abaf57d67","order_by":12,"name":"Bram Vanderborght","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Bram","middleName":"","lastName":"Vanderborght","suffix":""},{"id":400879022,"identity":"340ff1aa-efe0-4e81-902f-904bb0728844","order_by":13,"name":"Monika Rai","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Monika","middleName":"","lastName":"Rai","suffix":""},{"id":400879023,"identity":"ae33cf25-e8ca-4569-bf67-b9d2e8163d38","order_by":14,"name":"Wim Deferme","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+0lEQVRIiWNgGAWjYDACZiDmYZADMRkfMDaAhRoYIAy8WozBTAOISsbGBrxaGBBa2CSI0mJwnDuB4U2FgZz5tMPHqnl32NnLtze2P2DcYYNby2HeDYxzzhgYy9xOS7vNeyY5ccOZg0BbzqTh1GIG1MLM2/YncYZ0jtlt3jbmBAOJRKCWtsMEtPwzqJ8hnf+tmLet3l5+/kOQlv8EtDQYJEhI57ABrTvM2HAD5P22Azi12AO1HJxzzMBwhnSaseTctuNAvyQ2zkg8k4xTi2T/2Y0P3tQYyEtIJz/88LatGhhihw98+LjDDqcWEMDihgS8GkbBKBgFo2AUEAIAzYBX2MCnEtEAAAAASUVORK5CYII=","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Wim","middleName":"","lastName":"Deferme","suffix":""}],"badges":[],"createdAt":"2025-01-11 16:18:22","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-5810378/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5810378/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-025-19775-0","type":"published","date":"2025-10-15T00:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":99642308,"identity":"1f44a1d7-62ad-4b27-8a0d-8f32604d0268","added_by":"auto","created_at":"2026-01-06 19:01:00","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6980883,"visible":true,"origin":"","legend":"","description":"","filename":"Mainmanuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5810378/v1_covered_797b11b1-4b10-4650-8c6a-d132eb8232c4.pdf"},{"id":73820968,"identity":"bbadf087-b55c-4064-9679-b3f5a515781f","added_by":"auto","created_at":"2025-01-15 04:21:16","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":20890346,"visible":true,"origin":"","legend":"","description":"","filename":"Supporting.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5810378/v1/78b5a2db757464f318cb3681.pdf"},{"id":73820969,"identity":"91170103-d204-43e3-991c-0ffd629fcd2b","added_by":"auto","created_at":"2025-01-15 04:21:16","extension":"mp4","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":38070295,"visible":true,"origin":"","legend":"","description":"","filename":"Cycletester.mp4","url":"https://assets-eu.researchsquare.com/files/rs-5810378/v1/b92b32c933fcdd4f5dc88330.mp4"},{"id":73820970,"identity":"d015d6ca-ca0a-4e30-9719-20e3145ed64c","added_by":"auto","created_at":"2025-01-15 04:21:16","extension":"mp4","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":38070295,"visible":true,"origin":"","legend":"","description":"","filename":"Cycletester.mp4","url":"https://assets-eu.researchsquare.com/files/rs-5810378/v1/a900f3deb36f1a478d680d59.mp4"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eAutomated Spray Deposition of Liquid Metal: Process Assessment Towards Scalability and Reliability for Stretchable Electronics\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"Hasselt University","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Liquid Metal, Stretchable Electronics, Spray Deposition, Stencil Printing, Strain Sensor","lastPublishedDoi":"10.21203/rs.3.rs-5810378/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5810378/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLiquid metal stretchable electronics (LMSE) offer remarkable stretchability, softness, and self-healing properties, making them ideal for smart wearables and soft robotics. A key fabrication method involves spray deposition of LM into patterned structures. However, reliance on manual airbrush techniques has hindered understanding of how spray parameters impact LM deposition, limiting scalability and reliability. This work addresses these challenges by using an innovative automated spray coater (ASC), which provides precise control over deposition. For the first time, the ASC enables a systematic investigation of how spray parameters—such as flow rate, pressure, and spraying distance—affect LMSE properties like reliability, uniformity, and hysteresis. We find that rougher coatings improve yield (nearly 100\\%), but compromise long-term reliability. Additionally, finer linewidth patterns (0.25 mm) fail earlier in cyclic testing and show reduced self-healing capabilities compared to wider lines ($\u0026gt;0.5 mm$). The ASC's capabilities are demonstrated through the fabrication of LMSE devices, including a 16-LED array and a large wearable strain sensor (70 × 150 mm) for human motion capture. This work provides crucial insights into LM deposition and highlights relevant applications, advancing the development of scalable and reliable stretchable electronics.\u003c/p\u003e","manuscriptTitle":"Automated Spray Deposition of Liquid Metal: Process Assessment Towards Scalability and Reliability for Stretchable Electronics","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-15 04:21:11","doi":"10.21203/rs.3.rs-5810378/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b956e63b-2931-4d8f-a06f-de07b16195ef","owner":[],"postedDate":"January 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":42726933,"name":"Materials Engineering"}],"tags":[],"updatedAt":"2026-01-06T19:00:50+00:00","versionOfRecord":{"articleIdentity":"rs-5810378","link":"https://doi.org/10.1038/s41598-025-19775-0","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2025-10-15 00:00:00","publishedOnDateReadable":"October 15th, 2025"},"versionCreatedAt":"2025-01-15 04:21:11","video":"","vorDoi":"10.1038/s41598-025-19775-0","vorDoiUrl":"https://doi.org/10.1038/s41598-025-19775-0","workflowStages":[]},"version":"v1","identity":"rs-5810378","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5810378","identity":"rs-5810378","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}