Scalable, Modular Three-Dimensional Silicon Microelectrode Assembly via Electroless Plating.

Area of Science:

• Neuroscience
• Materials Science
• Electrical Engineering

Background:

• Current neural probes face limitations in scalability and recording density.
• Developing high-density, three-dimensional (3-D) neural probes is crucial for advanced brain-computer interfaces and neuroscience research.

Purpose of the Study:

• To devise a scalable and modular strategy for fabricating microfabricated 3-D neural probes.
• To demonstrate a novel assembly technique for creating complex 3-D neural probe architectures.

Main Methods:

• Utilized mechanical self-locking and self-aligning techniques to assemble individual 2-D components into 3-D probe structures.
• Employed electroless nickel plating to establish electrical connections between assembled probe components.
• Fabricated and tested various 3-D probe designs with thousands of electrode sites.

Main Results:

• Achieved high self-alignment accuracy between probe shanks (<0.2°).
• Demonstrated orthogonal electrical connections with a pitch of 40 µm, forming thousands of connections electrochemically in parallel.
• Successfully created scalable, modular electrodes suitable for high-density 3-D neural recording.

Conclusions:

• The developed fabrication strategy offers a scalable and modular approach for 3-D neural probe synthesis.
• This technology supports the design of high-density neural recording electrodes for large-scale brain activity mapping.
• The modular 3-D design and dense electrode configuration hold promise for advanced neural recording strategies in the mammalian brain.