{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T03:12:00Z","timestamp":1768792320884,"version":"3.49.0"},"reference-count":20,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2013,5,28]],"date-time":"2013-05-28T00:00:00Z","timestamp":1369699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>A procedure for fabrication of photomasks on photographic films with minimum feature achievable of about 20 \u03bcm, which are particularly suitable for the fast prototyping of microfluidic devices, has been improved. We used a commercial photographic enlarger in reverse mode obtaining 10:1 reduction factor with error less than 1%. Masks have been characterized by optical transmission measurement and contact profilometry: the exposed region completely absorbs light in the wavelength region explored, while the non-exposed region is transparent from 350 nm on; the average film thickness is of 410 nm and its roughness is about 120 nm. A PDMS microfluidic device has been realized and tested in order to prove the effectiveness of designed photomasks used with the common UV light box.<\/jats:p>","DOI":"10.3390\/mi4020206","type":"journal-article","created":{"date-parts":[[2013,5,28]],"date-time":"2013-05-28T12:17:33Z","timestamp":1369743453000},"page":"206-214","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Photomasks Fabrication Based on Optical Reduction for Microfluidic Applications"],"prefix":"10.3390","volume":"4","author":[{"given":"Emanuele","family":"Orabona","sequence":"first","affiliation":[{"name":"Department of Physics, University of Naples \"Federico II\", Via Cintia, 80128 Napoli, Italy"}]},{"given":"Alessandro","family":"Cali\u00f2","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Naples \"Federico II\", Via Cintia, 80128 Napoli, Italy"},{"name":"Institute for Microelectronics and Microsystems, Naples Unit, National Research Council, Via P. Castellino 111, 80131 Napoli, Italy"}]},{"given":"Ivo","family":"Rendina","sequence":"additional","affiliation":[{"name":"Institute for Microelectronics and Microsystems, Naples Unit, National Research Council, Via P. Castellino 111, 80131 Napoli, Italy"}]},{"given":"Luca","family":"Stefano","sequence":"additional","affiliation":[{"name":"Institute for Microelectronics and Microsystems, Naples Unit, National Research Council, Via P. Castellino 111, 80131 Napoli, Italy"}]},{"given":"Mario","family":"Medugno","sequence":"additional","affiliation":[{"name":"Institute for Microelectronics and Microsystems, Naples Unit, National Research Council, Via P. Castellino 111, 80131 Napoli, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2013,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1146\/annurev.matsci.28.1.153","article-title":"Soft lithography","volume":"28","author":"Xia","year":"1998","journal-title":"Annu. Rev. Mater. 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