Micromachined electrode arrays with form-fitting profile for auditory nerve prostheses

Area of Science:

• Biomedical Engineering
• Neuroprosthetics
• Microsystems Engineering

Background:

• Auditory nerve prostheses require precise electrode placement for effective neural stimulation.
• Current electrode designs face challenges in achieving a secure and conformal fit with the auditory nerve.
• Micromachining offers potential for creating high-density, miniaturized electrode arrays.

Purpose of the Study:

• To design, fabricate, and simulate a novel micromachined electrode array with a form-fitting profile for auditory nerve prostheses.
• To enhance the stability and sealing of the implant on the auditory nerve.
• To evaluate the mechanical and electrochemical performance of the proposed electrode array.

Main Methods:

• Fabrication of a 10x10 electrode array within a 1mm² area using bulk micromachining.
• Integration of a SU-8 layer to conform to the auditory nerve's curvature.
• Development of an electrical model for a single electrode.
• Mechanical and electrochemical finite element analyses (FEA) of the electrode array.

Main Results:

• Successful fabrication of a compact 10x10 electrode array.
• Demonstration of the SU-8 layer's ability to conform and seal.
• FEA results indicating suitable mechanical integrity and electrochemical performance for neural interface.

Conclusions:

• The novel micromachined electrode array with a form-fitting SU-8 layer shows promise for auditory nerve prostheses.
• The design facilitates secure implantation and effective sealing, potentially improving device performance.
• Further investigation and in vivo testing are warranted to validate its efficacy.