Thin film electrodes for brain computer interface and methods of microfabricating

A method for deploying a monolithic thin-film lead assembly, comprising:

• obtaining the lead assembly comprising:
• a cable comprising:
• a proximal end, a distal end, a supporting structure that extends from the proximal end to the distal end, and a plurality of conductive traces formed on a portion of the supporting structure, wherein the supporting structure is comprised of one or more layers of dielectric material, wherein a first portion of the supporting structure at the proximal end has a first type of helical structure, and wherein a second portion of the supporting structure between the first portion and the distal end has a second type of helical structure and is completely encased in a housing;
• an interface formed on the supporting structure at the distal end of the cable, wherein the interface comprises a plurality of electrodes and/or a plurality of sensors in electrical connection with one or more conductive traces of the plurality of conductive traces, wherein the plurality of electrodes comprise a first set of electrodes and a second set of electrodes and/or the plurality of sensors comprise a first set of sensors and a second set of sensors;
• and
• a guidewire comprising a stylet inserted through the interface, wherein while the stylet is inserted through the interface, the interface has a first profile, and wherein the first profile is straight with the first set of electrodes and the second set of electrodes and/or the first set of sensors and the second set of sensors provided in a linear array;
• inserting, with the guidewire, the lead assembly into a cavity of a subject;
• moving, with the guidewire, the lead assembly through the cavity to position the interface at a target location;
• and
• removing the guidewire and stylet from the cavity while leaving the lead assembly in place with the interface positioned at the target location, wherein removal of the stylet from the interface allows for the interface to take a second profile having at least one curved portion, wherein:
• (i) the at least one curved portion is disposed between the first set of electrodes and the second set of electrodes, and/or (ii) the at least one curved portion is disposed between the first set of sensors and the second set of sensors.