Hybrid Multisite Silicon Neural Probe with Integrated Flexible Connector for Interchangeable Packaging.

Area of Science:

• Neuroscience
• Materials Science
• Biomedical Engineering

Background:

• Multisite neural probes are crucial for understanding brain activity.
• Hybrid silicon/polymer probes offer advantages like complex geometries and flexible cabling.
• Limited availability has hindered the widespread adoption of hybrid probes.

Purpose of the Study:

• To develop, fabricate, and characterize a novel hybrid multisite multishank silicon neural probe.
• To assess the in vivo electrophysiological performance of the developed probe.
• To overcome fabrication and interfacing limitations of existing hybrid probes.

Main Methods:

• Optimized wafer-level fabrication for monolithic integration of silicon probes and polyimide flexible interconnect cables.
• Designed probes with 64 gold electrode sites on 8 shanks and an 8 µm thick flexible polyimide cable.
• Integrated a connector pad for direct mating with commercial zero-insertion force (ZIF) connectors.

Main Results:

• Successfully fabricated hybrid neural probes with the highest electrode site density and thinnest flexible cable reported for this class of device.
• Monolithic integration eliminated the need for post-fabrication cable bonding.
• Achieved high-density distributed in vivo electrophysiological recordings with low intrinsic noise and high signal-to-noise ratio (SNR).

Conclusions:

• The developed hybrid neural probe offers significant advancements in electrode density, flexibility, and ease of interfacing.
• Monolithic integration and ZIF connector compatibility enhance experimental flexibility and reproducibility.
• These probes represent a promising tool for high-fidelity neural recordings in neuroscience research.