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http://dx.doi.org/10.3795/KSME-A.2016.40.8.731

Hybrid UV Lithography for 3D High-Aspect-Ratio Microstructures  

Park, Sungmin (Dept. of Mechanical Engineering, Inha Univ.)
Nam, Gyungmok (Dept. of Mechanical Engineering, Inha Univ.)
Kim, Jonghun (Dept. of Mechanical Engineering, Inha Univ.)
Yoon, Sang-Hee (Dept. of Mechanical Engineering, Inha Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers A / v.40, no.8, 2016 , pp. 731-736 More about this Journal
Abstract
Three-dimensional (3D) high-aspect-ratio (HAR) microstructures for biomedical applications (e.g., microneedle, microadhesive, etc.) are microfabricated using the hybrid ultraviolet (UV) lithography in which inclined, rotational, and reverse-side UV exposure processes are combined together. The inclined and rotational UV exposure processes are intended to fabricate tapered axisymmetric HAR microstructures; the reverse-side UV exposure process is designed to sharpen the end tip of the microstructures by suppressing the UV reflection on a bottom substrate which is inevitable in conventional UV lithography. Hybrid UV lithography involves fabricating 3D HAR microstructures with an epoxy-based negative photoresist, SU-8, using our customized UV exposure system. The effects of hybrid UV lithography parameters on the geometry of the 3D HAR microstructures (aspect ratio, radius of curvature of the end tip, etc.) are measured. The dependence of the end-tip shape on SU-8 soft-baking condition is also discussed.
Keywords
Hybrid UV Lithography; Inclined Exposure; Rotational Exposure; Reverse-side Exposure; UV Reflection; High Aspect Ratio; Microstructure;
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Times Cited By KSCI : 1  (Citation Analysis)
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