Vertical Nanowire Probe Arrays for Scalable Intracellular Neural Recording
Solution Overview
Problem
Current technologies for studying electrophysiological states of excitable cells, such as neurons and cardiomyocytes, face limitations in scalability, invasiveness, and sensitivity, particularly with traditional patch-clamp methods and microelectrode arrays, which are not suitable for large-scale or long-term neural recordings and lack sub-cellular resolution.
Innovation Solution
A neural probe sensor array with individually addressable semiconductor vertical nanowires extending from a substrate, insulated with dielectric material, allowing for high-density, scalable, and minimally invasive intracellular recording and stimulation with sub-cellular resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional patch-clamp methods are used, then high-fidelity neural recordings are achieved, but scalability is limited to single channel or less than ten channels
Solution Approach 1:
The invention divides the recording system into multiple independent nanowire probes arranged in arrays, where each nanowire can independently access and record from individual cells. This segmentation enables simultaneous multi-channel recordings while maintaining the high fidelity of patch-clamp techniques, resolving the contradiction between recording quality and scalability.
Solution Approach 2:
The invention transitions from planar microelectrode arrays to three-dimensional vertical nanowire structures that can penetrate cell membranes. This dimensional change allows intracellular access while maintaining array scalability, enabling both high-fidelity intracellular recordings and multi-channel capability simultaneously.
2Productivity
If planar microelectrode arrays are used, then scalability to large numbers of probes is achieved, but access to cellular cytoplasm and measurement of intracellular potential changes is lost
Solution Approach 1:
The invention employs vertical nanowire structures extending perpendicular to the substrate plane, enabling penetration through cell membranes into the cytoplasm. This three-dimensional configuration maintains the scalability of array formats while restoring intracellular access and measurement capability that planar arrays cannot provide.
Solution Approach 2:
The nanowire tips are designed with specific local properties (small diameter, sharp tips) optimized for cell penetration and intracellular recording, while the base structures maintain electrical connectivity and array integration. This local differentiation enables both intracellular access and scalable array functionality.
3Manufacturing precision
If pitch below 1 μm is used in nanowire arrays, then sub-cellular resolution mapping is enabled, but fabrication complexity increases
Solution Approach 1:
The invention replaces traditional mechanical lithography and alignment methods with self-aligned fabrication processes where nanowires grow vertically from predefined contact pads. This substitution enables sub-micron pitch fabrication with reduced complexity by eliminating the need for precise mechanical alignment at each fabrication step.
Data Source
AI summary
A nanowire probe sensor array including a substrate with a metal pattern thereon. An array of semiconductor vertical nanowire probes extends away from the substrate, and at least some of probes, and preferably all, are individually electrically addressed through the metal pattern. The metal pattern is insulated with dielectric, and base and stem portions of the nanowires are also preferably insulated. A fabrication process patterns metal connections on a substrate. A semiconductor substrate is bonded to the metal pattern. The semiconductor substrate is etched to form the neural nanowire probes that are bonded to the metal pattern. Dielectric is then deposited to insulate the metal pattern.