{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:29:14Z","timestamp":1760243354776,"version":"build-2065373602"},"reference-count":21,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2014,10,17]],"date-time":"2014-10-17T00:00:00Z","timestamp":1413504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents an integrated high temperature ultrasonic transducer (HTUT) on a sensor insert and its application for real-time diagnostics of the conventional hot embossing process to fabricate V-cut patterns. The sensor was directly deposited onto the sensor insert of the hot embossing mold by using a sol-gel spray technique. It could operate at temperatures higher than 400 \u00b0C and uses an ultrasonic pulse-echo technique. The ultrasonic velocity could indicate the three statuses of the hot embossing process and also evaluate the replication of  V-cut patterns on a plastic plate under various processing conditions. The progression of the process, including mold closure, plastic plate softening, cooling and plate detachment inside the mold, was clearly observed using ultrasound. For an ultrasonic velocity range from  2197.4 to 2435.9 m\/s, the height of the V-cut pattern decreased from 23.0 to 3.2 \u00b5m linearly, with a ratio of \u22120.078 \u00b5m\/(m\/s). The incompleteness of the replication of the V-cut patterns could be indirectly observed by the ultrasonic signals. This study demonstrates the effectiveness of the ultrasonic sensors and technology for diagnosing the replicating condition of microstructures during the conventional hot embossing process.<\/jats:p>","DOI":"10.3390\/s141019493","type":"journal-article","created":{"date-parts":[[2014,10,17]],"date-time":"2014-10-17T10:27:19Z","timestamp":1413541639000},"page":"19493-19506","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Novel Real-Time Temperature Diagnosis of Conventional  Hot-Embossing Process Using an Ultrasonic Transducer"],"prefix":"10.3390","volume":"14","author":[{"given":"Chin-Chi","family":"Cheng","sequence":"first","affiliation":[{"name":"Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology, Taipei, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sen-Yeu","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dasheng","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology, Taipei, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,10,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1016\/S0167-9317(98)00135-X","article-title":"Hot embossing in polymers as a direct way to pattern resist","volume":"41","author":"Jaszewski","year":"1998","journal-title":"Microelectron. 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[1st ed.].","DOI":"10.1016\/B978-0-8155-1579-1.50014-8"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1007\/s005420050112","article-title":"Hot embossing\u2014The molding technique for plastic microstructures","volume":"4","author":"Heckele","year":"1998","journal-title":"Microsyst. Technol."},{"key":"ref_7","unstructured":"Hardt, D., Ganesan, B., Qi, W., Dirckx, M., and Rzepniewski, A. Process Control in Micro-Embossing: A Review. Available online: http:\/\/dspace.mit.edu\/handle\/1721.1\/3917."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Roos, N., Wissen, M., Glinsner, T., and Scheer, H.C. (2003, January 22\u201328). Impact of vacuum environment on the hot embossing process. Santa Clara, CA, USA.","DOI":"10.1117\/12.482750"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Roos, N., Luxbacher, T., Glinsner, T., Pfeiffer, K., Schulz, H., and Scheer, H.C. (2001). Nanoimprint lithography with a commercial 4 inch bond system for hot embossing. Proc. SPIE Emerg. Lithogr. Technol. V, 4343.","DOI":"10.1117\/12.436661"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1177\/073168449901800403","article-title":"Ultrasound: A virtual instrument approach for monitoring of polymer melt variables","volume":"18","author":"Brown","year":"1999","journal-title":"J. Reinf. Plast. Compos."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1491","DOI":"10.1002\/pen.20852","article-title":"Real-time diagnosis of co-injection molding using ultrasound","volume":"47","author":"Cheng","year":"2007","journal-title":"Polym. Eng. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"606","DOI":"10.1002\/pen.20310","article-title":"Real-Time Monitoring of Injection Moulding for Microfluidic Devices using Ultrasound","volume":"45","author":"Ono","year":"2005","journal-title":"Polym. Eng. 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