Fabrication Feasibility of SU8 Waveguides and Gold Electrodes via Lift-Off-Based Micromachining Process

Subject Areas :

Parisa Mahmoudi ^{1 *}

1 - Assistant Professor, Department of Electrical Engineering, Payame Noor University, Tehran, Iran

Received: 2025-06-25 Accepted : 2025-08-14 Published : 2025-05-15

Keywords: Microfabrication, Lift-off, Photolithography, UV Exposure, Deposition, SU8,

Abstract :

Brain interfaces are advanced systems designed to combine optical waveguides for neural stimulation with electrodes for recording neural activity. The microfabrication process for developing such compact devices is challenging and critical to their performance and application. However, conventional fabrication techniques often involve stacking layers of different substrates for each of the stimulation and recording components, resulting in bulky designs that increase the risk of invasiveness. This issue makes the implants less practical for neuroscience studies. This research assesses a simple method for assembling SU8 waveguides with Au electrodes on a single substrate. It utilizes the lift-off technique to fabricate electrodes directly onto the waveguide, routing down to the same primary substrate. The introduced method eliminates the need for depositing additional layers as a base for electrode formation. The results demonstrated the successful feasibility and assembly of the structure without relying on a common stacked and thick configuration.

References:

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