{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T12:40:02Z","timestamp":1765888802012,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,8]],"date-time":"2022-02-08T00:00:00Z","timestamp":1644278400000},"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 Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/CTM-CTM\/31953\/2017"],"award-info":[{"award-number":["PTDC\/CTM-CTM\/31953\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>For decades, Ta\/TaN has been the industry standard for a diffusion barrier against Cu in interconnect metallisation. The continuous miniaturisation of transistors and interconnects into the nanoscale are pushing conventional materials to their physical limits and creating the need to replace them. Binary metallic systems, such as Ru-W, have attracted considerable attention as possible replacements due to a combination of electrical and diffusion barrier properties and the capability of direct Cu electroplating. The process of Cu electrodeposition on Ru-W is of fundamental importance in order to create thin, continuous, and adherent films for advanced interconnect metallisation. This work investigates the effects of the current density and application method on the electro-crystallisation behaviour of Cu. The film structure, morphology, and chemical composition were assessed by digital microscopy, atomic force microscopy, scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The results show that it was possible to form a thin Cu film on Ru-W with interfacial continuity for current densities higher than 5 mA\u00b7cm\u22122; however, the substrate regions around large Cu particles remained uncovered. Pulse-reverse current application appears to be more beneficial than direct current as it decreased the average Cu particle size.<\/jats:p>","DOI":"10.3390\/ijms23031891","type":"journal-article","created":{"date-parts":[[2022,2,8]],"date-time":"2022-02-08T23:37:48Z","timestamp":1644363468000},"page":"1891","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Seedless Cu Electroplating on Ru-W Thin Films for Metallisation of Advanced Interconnects"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5845-5698","authenticated-orcid":false,"given":"R\u00faben F.","family":"Santos","sequence":"first","affiliation":[{"name":"Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI\u2013Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3920-6511","authenticated-orcid":false,"given":"Bruno M. C.","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI\u2013Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal"}]},{"given":"Liliane C. G.","family":"Savaris","sequence":"additional","affiliation":[{"name":"Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"given":"Paulo J.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"International Iberian Nanotechnology Laboratory, 4710-330 Braga, Portugal"},{"name":"Materials Science and Engineering Program, University of Texas at Austin, Austin, TX 78712, USA"},{"name":"Mechanical Engineering Department and IDMEC, IST, University of Lisbon, 1749-016 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3667-0562","authenticated-orcid":false,"given":"Manuel F.","family":"Vieira","sequence":"additional","affiliation":[{"name":"Department of Metallurgical and Materials Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI\u2013Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,8]]},"reference":[{"key":"ref_1","first-page":"24","article-title":"Current Status and Advances in Damascene Electrodeposition, Encyclopedia of Interfacial Chemistry","volume":"5.1","author":"Akolar","year":"2018","journal-title":"Surf. 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