{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T21:38:27Z","timestamp":1768858707983,"version":"3.49.0"},"reference-count":29,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T00:00:00Z","timestamp":1768780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IPL\/IDI&CA2024\/OPAPIC2D_ISEL project"},{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a ci\u00eancia de tecnlogia CST\/00066 project ASER_META","doi-asserted-by":"publisher","award":["PTDC\/2022.07694.PTDC"],"award-info":[{"award-number":["PTDC\/2022.07694.PTDC"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"SYNOPSYS OSG University Donation Program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The development of photonic-integrated circuits (PICs) for data communication, sensing, and quantum computing is hindered by the high complexity and cost of traditional fabrication methods, which rely on expensive equipment, limiting accessibility for research and prototyping. This study introduces a Direct Laser Writing (DLW) system designed as a low-cost alternative, utilizing an XY platform for precise substrate movement and an optical system comprising a collimator and lens to focus the laser beam. Operating on a single layer, the system employs SU-8 photoresist to fabricate polymer-based structures on substrates such as ITO-covered glass. Preparation involves thorough cleaning, spin coating with photoresist, and pre- and post-baking to ensure material stability. This approach reduces dependence on costly infrastructure, making it suitable for academic settings and enabling rapid prototyping. A user interface and custom slicer process standard .dxf files into executable commands, enhancing operational flexibility. Experimental results demonstrate a resolution of 10 \u00b5m, with successful patterning of structures, including diffraction grids, waveguides, and multimode interference devices. This system aims to transform PIC prototype fabrication into a cost-effective, accessible process.<\/jats:p>","DOI":"10.3390\/mi17010125","type":"journal-article","created":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T08:23:56Z","timestamp":1768811036000},"page":"125","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Low-Cost DLW Setup for Fabrication of Photonics-Integrated Circuits"],"prefix":"10.3390","volume":"17","author":[{"given":"Andr\u00e9","family":"Moreira","sequence":"first","affiliation":[{"name":"Departamento de Engenharia Electr\u00f3nica e Telecomunica\u00e7\u00f5es e de Computadores, Instituto Superior de Engenharia de Lisboa (ISEL), 1959-007 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-0351","authenticated-orcid":false,"given":"Alessandro","family":"Fantoni","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Electr\u00f3nica e Telecomunica\u00e7\u00f5es e de Computadores, Instituto Superior de Engenharia de Lisboa (ISEL), 1959-007 Lisboa, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Laboratory of Intelligent Systems (LASI), Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0765-474X","authenticated-orcid":false,"given":"Miguel","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Electr\u00f3nica e Telecomunica\u00e7\u00f5es e de Computadores, Instituto Superior de Engenharia de Lisboa (ISEL), 1959-007 Lisboa, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Laboratory of Intelligent Systems (LASI), Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2027-4901","authenticated-orcid":false,"given":"Jorge","family":"Fidalgo","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Electr\u00f3nica e Telecomunica\u00e7\u00f5es e de Computadores, Instituto Superior de Engenharia de Lisboa (ISEL), 1959-007 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,19]]},"reference":[{"key":"ref_1","first-page":"128770G","article-title":"Photonic integrated circuits for high-throughput optical communications and ranging satellite links","volume":"Volume 12877","author":"Ziarko","year":"2024","journal-title":"Free-Space Laser Communications XXXVI"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zhu, H., Lin, H., Wu, S., Luo, W., Zhang, H., Zhan, Y., Wang, X., Liu, A., and Kwek, L.C. 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