{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T17:04:28Z","timestamp":1774285468163,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2014,12,23]],"date-time":"2014-12-23T00:00:00Z","timestamp":1419292800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>SU-8 has been widely used in a variety of applications for creating structures in micro-scale as well as sub-micron scales for more than 15 years. One of the most common structures made of SU-8 is tall (up to millimeters) high-aspect-ratio (up to 100:1) 3D microstructure, which is far better than that made of any other photoresists. There has been a great deal of efforts in developing innovative unconventional lithography techniques to fully utilize the thick high aspect ratio nature of the SU-8 photoresist. Those unconventional lithography techniques include inclined ultraviolet (UV) exposure, back-side UV exposure, drawing lithography, and moving-mask UV lithography. In addition, since SU-8 is a negative-tone photoresist, it has been a popular choice of material for multiple-photon interference lithography for the periodic structure in scales down to deep sub-microns such as photonic crystals. These innovative lithography techniques for SU-8 have led to a lot of unprecedented capabilities for creating unique micro- and nano-structures. This paper reviews such innovative lithography techniques developed in the past 15 years or so.<\/jats:p>","DOI":"10.3390\/mi6010001","type":"journal-article","created":{"date-parts":[[2014,12,23]],"date-time":"2014-12-23T15:33:56Z","timestamp":1419348836000},"page":"1-18","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":80,"title":["Innovative SU-8 Lithography Techniques and Their Applications"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4349-9732","authenticated-orcid":false,"given":"Jeong","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, University of Texas, Dallas, Richardson, TX 75080, USA"}]},{"given":"Kyung-Hak","family":"Choi","sequence":"additional","affiliation":[{"name":"Siliconfile Technologies, Inc., Seongnam-si, Gyeonggi-do 463-050, Korea"}]},{"given":"Koangki","family":"Yoo","sequence":"additional","affiliation":[{"name":"Department of Information and Communication Engineering, Hanbat National University, Daejeon 305-719, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2014,12,23]]},"reference":[{"key":"ref_1","unstructured":"LaBianca, N.C., and Gelorme, J.D. 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