Process for manufacturing electronically conductive components

Abstract

A method of forming a device, such as an electrode array for a cochlear implant. The method comprises a step of forming a predetermined pattern of relatively electrically conductive regions and relatively electrically resistive regions in a sheet of biocompatible electrically conductive material, such as platinum foil. The method can comprise a step of working on the sheet to remove predetermined portions therefrom to form the one or more discrete relatively conducting regions. The step of working on the sheet can comprise embossing the sheet, cutting or slicing the sheet, or using electrical discharge machining (EDM) to remove unwanted portions of the sheet, the EDM equipment having a cutting tool comprising an electrode.

1 . A method of forming a device comprised of a predetermined pattern of relatively electrically conductive regions and relatively electrically resistive regions, the method comprising a step of: 
 working a sheet of electrically conductive material to remove predetermined portions therefrom to form said one or more discrete relatively conducting regions;    wherein the step of working the sheet includes a step of pressing a sheet of electrically conductive material to form a predetermined pattern of raised portions therein; and    wherein one or more of those portions of the sheet not raised during the pressing step are removed to leave a remaining portion having a predetermined pattern.    
   
   
       2 . A method of forming a device comprised of a predetermined pattern of relatively electrically conductive regions and relatively electrically resistive regions, the method comprising a step of: 
 working a sheet of electrically conductive material to remove predetermined portions therefrom to form said one or more discrete relatively conducting regions;    wherein the step of working the sheet includes a step of pressing a sheet of electrically conductive material to form a predetermined pattern of raised portions therein; and    wherein at least some of the raised portions and at least some of the unraised portion are removed to leave a remaining portion having a predetermined pattern.    
   
   
       3 . A method of forming a device comprised of a predetermined pattern of relatively electrically conductive regions and relatively electrically resistive regions, the method comprising the steps of: 
 (i) coating at least a first surface of an electrically conductive material with a first layer of another material that is relatively electrically insulating;    (ii) forming a predetermined pattern in the sheet of electrically conductive material by removing portions of the sheet therefrom such that at least the pattern of electrically conductive regions remain; and    (iii) coating a second surface of the sheet of electrically conductive material with a layer of resiliently flexible material;    wherein the first layer comprises a polymeric material selected from the group comprising a polycarbonate, polytetrafluoroethylene, polyimide, PAA, and PVA; and    wherein the device is a component of an implantable tissue-stimulating device.    
   
   
       4 . A device of  claim 3  wherein the tissue-stimulating device is an intracochlear electrode assembly.  
   
   
       5 . An electrode array for use in a tissue stimulating or recording device, the electrode array comprising a plurality of stimulating or recording pads, each stimulating or recording pad having at least one electrical conduction means extending away therefrom, the stimulating or recording pads and electrical conduction means formed from a worked sheet of electrically conducting material.  
   
   
       6 . The electrode array of  claim 5  wherein the sheet is a sheet of platinum.  
   
   
       7 . The electrode array of  claim 5  wherein the stimulating pads and at least a portion of the electrical conduction means are housed within an elongate biocompatible carrier.  
   
   
       8 . The electrode array of  claim 7  wherein the sheet of platinum has a thickness no greater than about 50 microns.  
   
   
       9 . The electrode array of  claim 8  wherein the sheet of platinum has a thickness no greater than about 20 microns.  
   
   
       10 . The electrode array of  claim 5  wherein each electrode has an areal dimension of less than about 0.5 mm 2 .  
   
   
       11 . The electrode array of  claim 5  wherein the sheet has a dimension of about 50 mm×250 mm.  
   
   
       12 . The electrode array of  claim 11  wherein more than one electrode array is formed from a single sheet of platinum.  
   
   
       13 . The electrode array of  claim 5  wherein the electrical conduction means have a width of between about 1 and 100 microns, more preferably between about 1 and 70 microns.  
   
   
       14 . The electrode array of  claim 13  wherein each electrical conduction means is electrically insulated from its neighbour, the spacing between neighbouring wires being between about 10 and 100 microns.  
   
   
       15 . The electrode array of  claim 5  wherein the array is formed by pressing the sheet of electrically conductive material to form raised and unraised portions and then removing the raised or unraised portions to leave a remaining portion having a predetermined pattern of electrically conductive and electrically resistive regions.  
   
   
       16 . The electrode array of  claim 5  wherein the array is formed by machining the sheet of electrically conductive material to remove a portion therefrom such that at least a pattern of electrically conductive regions remains.  
   
   
       17 . The electrode array of  claim 16  wherein the machining of the sheet comprises a step of using electrical discharge machining (EDM) to remove unwanted portions of the sheet.  
   
   
       18 . A device having an electrically conductive component, the component being formed from a worked sheet of electrically conducting material, the sheet having a thickness less than about 50 microns.  
   
   
       19 . The device of  claim 18  wherein the sheet is a platinum foil.  
   
   
       20 . The device of  claim 19  wherein the platinum foil has a thickness no greater than about 20 microns.  
   
   
       21 . The device of  claim 19  wherein the sheet has a dimension of about 50 mm×250 mm.  
   
   
       22 . The device of  claim 18  wherein the electrically conductive component comprises at least one conductive wire formed from the platinum foil, the wire having a width of between about 1 and 100 microns, more preferably between about 1 and 70 microns.  
   
   
       23 . The device of  claim 22  wherein the electrically conductive component comprises a plurality of discrete conductive wires formed from the platinum foil, each wire being electrically insulated from its neighbouring wire.  
   
   
       24 . The device of  claim 23  wherein the spacing between neighbouring wires is between about 10 and 100 microns.  
   
   
       25 . The device of  claim 24  wherein the wires are disposed for at least a portion of their lengths in a parallel arrangement.  
   
   
       26 . The device of  claim 21  wherein the conductive wire extends from an electrode also formed from the platinum foil, the electrode having an areal dimension of less than about 0.5 mm 2 .  
   
   
       27 . The device of  claim 18  wherein the device is a component of a tissue stimulating device.  
   
   
       28 . The device of  claim 27  wherein the tissue stimulating device is an intracochlear electrode assembly.  
   
   
       29 . The device of  claim 18  wherein the device is a component of a biosensor.  
   
   
       30 . The device of  claim 18  wherein the device is a miniature wire.  
   
   
       31 . The device of  claim 18  wherein the component is formed by machining the sheet of electrically conductive material to remove a portion therefrom such that at least a pattern of electrically conductive regions remains.  
   
   
       32 . The device of  claim 31  wherein the machining of the sheet comprises a step of using electrical discharge machining (EDM) to remove unwanted portions of the sheet.  
   
   
       33 . A method of forming a device comprised of a predetermined pattern of relatively electrically conductive regions and relatively electrically resistive regions, the method comprising the steps of: 
 (i) mounting a sheet of electrically conductive material in an electrical discharge machining (EDM) device, the device having a discharge electrode of a predetermined shape;    (ii) programming the EDM device to bring the electrode adjacent the sheet; and    (iii) operating the EDM device to remove a portion of the sheet corresponding to the shape of the electrode.