Fabrication of an insulated probe on a self-assembled metallic nanowire for electrochemical probing in cells

Conductive nanowire probes that are stiff enough too be inserted inside individual cells could provide unprecedented detail in real-time about the chemistry of living cells and cell compartments including cell membranes, cytosolic organelles and the nucleus. Localization also requires that the probe is insulated except at its end. To enable simple interconnection to an experimental apparatus, the nanowire would need to be attached to a larger platform, e.g. a MEMS device or cantilever (such as used in atomic force microscopes-AFM.) Such a device with 100 nm or less diameter can be fabricated with only a few processing steps by taking advantage of a previously reported technique for self-assembling metal alloy nanowires at selected locations and with desired orientations with respect to the surface [1]. In this report such a concept device and its fabrication process is reported. All steps have been individually demonstrated, although the complete fabrication from end-to-end has yet to be demonstrated at the time of this writing.