My goal was to fabricate a nanowire pattern on a thin layer of gold with laser interference lithography. The advantage of the process is that you can create a significantly smaller pattern (typically 100 nm), than the wavelength of the light used for the fabrication or the focus diameter of the laser. After creating a pattern in the photoresist with interference lithography a subtractive method (etching) is used to create gold nanowires. The nanowires, fabricated on a glass substrate are used to enhance the signal of surface plasmon resonance imaging.
I designed and implemented a Lloyd’s mirror interferometer for the fabrication of nanowires considering the infrastructure and possibilities of the Department of Electronics Technology. Some part tasks were needed to be done for the optical composition such as solving the beam expanding and designing a tool that can fix the mirror and the substrate. I designed the base of the interferometer with Autodesk Inventor program which was printed with a 3D printer. With the assembled experimental composition I did preliminary measurements for the fabrication of nanowires that were characterised with atomic force microscopy. I could create a pattern that was the result of the exposure, however I realised that for the fabrication of precise 100 nm wide nanowires further optimization is needed.