{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T15:58:03Z","timestamp":1774281483767,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,12,6]],"date-time":"2018-12-06T00:00:00Z","timestamp":1544054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PEst-C\/CTM\/LA0011\/2013, IF\/00602\/2013"],"award-info":[{"award-number":["PEst-C\/CTM\/LA0011\/2013, IF\/00602\/2013"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Coatings"],"abstract":"<jats:p>If piezoelectric thin films sensors based on K0.5Na0.5NbO3 (KNN) are to achieve commercialization, it is critical to optimize the film performance using low-cost scalable processing and substrates. Here, sol\u2013gel derived KNN thin films are deposited using a solution with 5% of potassium excess on Pt\/TiO2\/SiO2\/Si and Pt\/SrTiO3 substrates, and rapid thermal annealed at 750 \u00b0C for 5 min. Despite an identical film morphology and thickness of ~335 nm, an in-plane stress\/strain state is found to be tensile for KNN films on Pt\/TiO2\/SiO2\/Si, and compressive for those on Pt\/SrTiO3 substrates, being related to thermal expansion mismatch between the substrate and the film. Correspondingly, KNN films under in-plane compressive stress possess superior dielectric permittivity and polarization in the parallel-plate-capacitor geometry.<\/jats:p>","DOI":"10.3390\/coatings8120449","type":"journal-article","created":{"date-parts":[[2018,12,7]],"date-time":"2018-12-07T03:46:14Z","timestamp":1544154374000},"page":"449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Strain-Mediated Substrate Effect on the Dielectric and Ferroelectric Response of Potassium Sodium Niobate Thin Films"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0318-9262","authenticated-orcid":false,"given":"Alexander","family":"Tkach","sequence":"first","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Andr\u00e9","family":"Santos","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Sebastian","family":"Zlotnik","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Institute of Electronic Materials Technology (ITME), Wolczynska 133, 01-919 Warsaw, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8531-090X","authenticated-orcid":false,"given":"Ricardo","family":"Serrazina","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0885-7127","authenticated-orcid":false,"given":"Olena","family":"Okhay","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Nanotechnology Research Division, Centre for Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6318-1425","authenticated-orcid":false,"given":"Igor","family":"Bdikin","sequence":"additional","affiliation":[{"name":"Nanotechnology Research Division, Centre for Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Maria Elisabete","family":"Costa","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Paula M.","family":"Vilarinho","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramics Engineering, CICECO\u2013Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3677","DOI":"10.1111\/jace.12715","article-title":"(K,Na)NbO3-based lead-free piezoceramics: Fundamental aspects, processing technologies, and remaining challenges","volume":"96","author":"Li","year":"2013","journal-title":"J. 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