Novel glass microprobe arrays for neural recording

Area of Science:

• Neuroscience
• Materials Science
• Electrical Engineering

Background:

• Probe arrays are crucial for detecting neural signals in neurophysiology.
• Microfabricated probes offer advantages like fine spacing and smaller footprints.
• Glass offers superior signal isolation and biocompatibility compared to traditional materials.

Purpose of the Study:

• To present a novel fabrication process for a glass 2D-microprobe array.
• To enable vertical integration of microprobe chips using through-silicon vias (TSVs).
• To demonstrate the application of the glass microprobe for neural signal recording.

Main Methods:

• Micromachining process to create glass 2D-microprobe arrays.
• Integration of through-silicon vias (TSVs) for vertical chip assembly.
• Fabrication and characterization of the glass microprobe, including impedance measurements.
• Recording of neural signals from crayfish nerve cord and rat cortex.

Main Results:

• The fabricated 2D glass microprobe exhibited a low impedance of 439 kΩ at 1 kHz.
• Successfully recorded action potentials from crayfish nerve cord (228 μV amplitude, SNR 46.42).
• Successfully recorded spontaneous spikes from rat cortex (90 μV amplitude, SNR 19.72).

Conclusions:

• The novel glass 2D-microprobe array is a viable tool for neurophysiological recordings.
• The integration of TSVs facilitates the development of 3D microprobe arrays.
• The demonstrated performance highlights the potential of glass microprobes for advanced neural interface applications.