{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T13:20:10Z","timestamp":1775481610999,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2016,3,4]],"date-time":"2016-03-04T00:00:00Z","timestamp":1457049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["275117"],"award-info":[{"award-number":["275117"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Soft micro devices and stretchable electronics have attracted great interest for their potential applications in sensory skins and wearable bio-integrated devices. One of the most important steps in building printed circuits is the alignment of assembled micro objects. Previously, the capillary self-alignment of microchips driven by surface tension effects has been shown to be able to achieve high-throughput and high-precision in the integration of micro parts on rigid hydrophilic\/superhydrophobic patterned surfaces. In this paper, the self-alignment of microchips on a patterned soft and stretchable substrate, which consists of hydrophilic pads surrounded by a superhydrophobic polydimethylsiloxane (PDMS) background, is demonstrated for the first time. A simple process has been developed for making superhydrophobic soft surface by replicating nanostructures of black silicon onto a PDMS surface. Different kinds of PDMS have been investigated, and the parameters for fabricating superhydrophobic PDMS have been optimized. A self-alignment strategy has been proposed that can result in reliable self-alignment on a soft PDMS substrate. Our results show that capillary self-alignment has great potential for building soft printed circuits.<\/jats:p>","DOI":"10.3390\/mi7030041","type":"journal-article","created":{"date-parts":[[2016,3,4]],"date-time":"2016-03-04T10:53:34Z","timestamp":1457088814000},"page":"41","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Capillary Self-Alignment of Microchips on Soft Substrates"],"prefix":"10.3390","volume":"7","author":[{"given":"Bo","family":"Chang","sequence":"first","affiliation":[{"name":"Department of Engineering Sciences, Uppsala University, SE-75121 Uppsala, Sweden"},{"name":"Department of Applied Physics, School of Science, Aalto University, FI-00076 Aalto, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3819-3878","authenticated-orcid":false,"given":"Quan","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Automation, Aalto University, FI-00076 Aalto, Finland"}]},{"given":"Zhigang","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences, Uppsala University, SE-75121 Uppsala, Sweden"},{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China"}]},{"given":"Zhenhua","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2076-242X","authenticated-orcid":false,"given":"Robin","family":"Ras","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, School of Science, Aalto University, FI-00076 Aalto, Finland"}]},{"given":"Klas","family":"Hjort","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences, Uppsala University, SE-75121 Uppsala, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2016,3,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"034104","DOI":"10.1063\/1.3615053","article-title":"Capillary-driven self-assembly of microchips on oleophilic\/oleophobic patterned surface using adhesive droplet in ambient air","volume":"99","author":"Chang","year":"2011","journal-title":"Appl. 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