Abstract:
Polymer materials are useful as electrode array bodies for neural stimulation. They are particularly useful for retinal stimulation to create artificial vision, cochlear stimulation to create artificial hearing, and cortical stimulation, and many related purposes. The pressure applied against the retina, or other neural tissue, by an electrode array is critical. Too little pressure causes increased electrical resistance, along with electric field dispersion. Too much pressure may block blood flow. Common flexible circuit fabrication techniques generally require that a flexible circuit electrode array be made flat. Since neural tissue is almost never flat, a flat array will necessarily apply uneven pressure. Further, the edges of a flexible circuit polymer array may be sharp and cut the delicate neural tissue. By applying the right amount of heat to a completed array, a curve can be induced. With a thermoplastic polymer it may be further advantageous to repeatedly heat the flexible circuit in multiple molds, each with a decreasing radius. Further, it is advantageous to add material along the edges. It is further advantageous to provide a fold or twist in the flexible circuit array. Additional material may be added inside and outside the fold to promote a good seal with tissue.
Abstract:
The present invention is an improved hermetic package for implantation in the human body. The implantable device comprises an electrically non-conductive substrate; a plurality of electrically conductive vias through said electrically non-conductive substrate; a flip-chip circuit attached to said electrically non-conductive substrate using conductive bumps and electrically connected to a first subset of said plurality of electrically conductive vias, wherein said flip-chip circuit contains one or more stacks or a folded stack; a wire bonded circuit attached to said electrically non-conductive substrate and electrically connected to a second subset of said electrically conductive vias; and a cover bonded to said electrically non-conductive substrate, said cover, said electrically non-conductive substrate and said electrically conductive vias forming a hermetic package.
Abstract:
An implantable hermetically sealed microelectronic device and method of manufacture are disclosed. The microelectronic device of the present invention is hermetically encased in a insulator, such as alumina formed by ion bean assisted deposition (“IBAD”), with a stack of biocompatible conductive layers extending from a contact pad on the device to an aperture in the hermetic layer. In a preferred embodiment, one or more patterned titanium layers are formed over the device contact pad, and one or more platinum layers are formed over the titanium layers, such that the top surface of the upper platinum layer defines an external, biocompatible electrical contact for the device. Preferably, the bottom conductive layer is larger than the contact pad on the device, and a layer in the stack defines a shoulder.
Abstract:
An implantable hermetically sealed microelectronic device and method of manufacture are disclosed. The microelectronic device of the present invention is hermetically encased in a insulator, such as alumina formed by ion bean assisted deposition (“IBAD”), with a stack of biocompatible conductive layers extending from a contact pad on the device to an aperture in the hermetic layer. In a preferred embodiment, one or more patterned titanium layers are formed over the device contact pad, and one or more platinum layers are formed over the titanium layers, such that the top surface of the upper platinum layer defines an external, biocompatible electrical contact for the device. Preferably, the bottom conductive layer is larger than the contact pad on the device, and a layer in the stack defines a shoulder.
Abstract:
The invention involves a flexible circuit electrode array device comprising: a polymer layer; wherein the polymer layer includes one or more metal traces, an electrode array; one or more bond pads; and the electrode array is located on the opposite side of the polymer layer.The invention further involves a method for backside processing of a flexible circuit electrode device, comprising: applying polymer film on a substrate; processing the front side; releasing the polymer film from substrate; flipping over the polymer film and fixing it onto the substrate; processing the backside; and final releasing of the polymer film from the substrate.The invention further involves a method for backside processing of a flexible circuit electrode device, comprising: processing the front side without releasing the polymer; processing the backside by sacrificial substrate method, or by laser drilling method; and releasing the polymer film from the substrate.
Abstract:
A cochlear stimulation device comprising an electrode array designed to provide enhanced charge injection capacity necessary for neural stimulation. The electrode array comprises electrodes with high surface area or a fractal geometry and correspondingly high electrode capacitance and low electrical impedance. The resultant electrodes have a robust surface and sufficient mechanical strength to withstand physical stress vital for long term stability. The device further comprises wire traces having a multilayer structure which provides a reduced width for the conducting part of the electrode array. The cochlear prosthesis is attached by a grommet to the cochleostomy that is made from a single piece of biocompatible polymer. The device, designed to achieve optimum neural stimulation by appropriate electrode design, is a significant improvement over commercially available hand-built devices.
Abstract:
The disclosure relates to a flexible circuit electrode array comprising: a polymer base layer; metal traces deposited on said polymer base layer, including electrodes suitable to stimulate neural tissue; a polymer top layer deposited on said polymer base layer and said metal traces; and at least one support embedded in said array. The disclosure further relates to a flexible circuit electrode array comprising: a polymer base layer; metal traces deposited on said polymer base layer, including electrodes suitable to stimulate neural tissue; a polymer top layer deposited on said polymer base layer and said metal traces; and a folded flexible circuit cable connecting the electrode array with an interconnection pad. The disclosure further relates to a method of making a flexible circuit electrode array comprising: depositing a polymer base layer; depositing metal on said polymer base layer; patterning said metal to form metal traces; depositing a polymer top layer on said polymer base layer and said metal traces; heating said flexible circuit electrode array in a mold to form a three dimensional shape in said flexible circuit electrode array, embedding a support at least in the base layer, top layer or between the base and top layer, and/or folding a flexible circuit cable at least once connecting the electrode array with an interconnection pad the array.
Abstract:
The present invention relates to a process for embedding at least one layer of at least one metal trace in a silicone containing polymer, comprising: a) applying a non adhering on a substrate; b) applying a polymer layer on the non adhering agent; c) irradiation at least one surface area of said polymer with a light beam emitted by an excimer laser; d) immersing said irradiated polymer in at least one autocatalytic bath containing metal ions of at least one metal and metallizing the polymer; e) thermally treating said metallized polymer; f) applying a polymer layer on said thermally treated metallized polymer; and g) thermally treating said metallized polymer.
Abstract:
The present invention consists of an implantable device with at least one package that houses electronics that sends and receives data or signals, and optionally power, from an external system through at least one coil attached to the at least one package and processes the data, including recordings of neural activity, and delivers electrical pulses to neural tissue through at least one array of multiple electrodes that is/are attached to the at least one package. The device is adapted to electrocorticographic (ECoG) and local field potential (LFP) signals. The output signals provide control for a motor prosthesis and the inputs signals provide sensory feedback for the motor prosthesis. The invention, or components thereof, is/are intended to be installed in the head, or on or in the cranium or on the dura, or on or in the brain.
Abstract:
The present invention provides a flexible circuit electrode array adapted for neural stimulation, comprising: a polymer base layer; metal traces deposited on the polymer base layer, including electrodes suitable to stimulate neural tissue; a polymer top layer deposited on the polymer base layer and the metal traces at least one tack opening. The present invention provides further a method of making a flexible circuit electrode array comprising depositing a polymer base layer; depositing metal on the polymer base layer; patterning the metal to form metal traces; depositing a polymer top layer on the polymer base layer and the metal traces; and preparing at least one tack opening.