Fabrication of three-dimensional hemispherical structures using photolithography
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Abstract
A photolithography technique using SU-8 and PDMS was developed to fabricate three-dimensional hemispherical structures. This technique utilized a mask-aligner and normal binary coded photomasks to generate hemispherical pits on SU-8, followed by PDMS molding to obtain an array of dome-shaped structures. Using this technique, a microfluidic device was fabricated with a patterning area that consisted of an array of 5 μm wells and dome-shaped structures with 10 μm diameter and 6 μm height. Encoded microbeads, 6 μm in size, were immobilized and patterned in the microfluidic device under flow conditions and a DNA hybridization experiment was performed to demonstrate the incorporation of encoded beads that would enable a high level of multiplexing in bioassays.
Keywords
3D structures Microfluidics Photolithography SU-8 Soft lithographyNotes
Acknowledgments
We would like to acknowledge the funding of this research work by the National University of Singapore, WBS no: R-397-000-027-112.
Supplementary material
References
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