Date of Submission
Academic Programs and Concentrations
Project Advisor 1
Presented here is a straightforward and cost-effective hybrid lithography technique. The process uses mask-based photolithography to pattern coarse features and direct laser writing (DLW) to customize features as small as 6 μm using a 20ｘ0.75 NA objective in SU-8, a widely used and commercially available photoresist. SU-8 doped with fluorescein (SU-8F) enabled its use for hybrid lithography because it shows contrast following exposure, as areas exposed absorb in the 450 nm region and unexposed areas do not. On average, DLW features written in SU-8 were 4.7 μm wider than features written in SU-8F. The DLW optical microscope was modified with a 450 nm filter to illuminate the sample, which caused mask-pattern features to appear opaque. The addition of fluorescein to SU-8 decreases its the ability to adhere to a silicon substrate. Using hybrid lithography, we were able to precisely pattern an interdigitated electrode in between two 110 μm leads on a silicon wafer.
Open Access Agreement
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Clifton, Garrett Michael, "Hybrid Lithography in SU-8: A Masked-Based Photolithography and Direct Laser Writing Technique" (2017). Senior Projects Spring 2017. 153.