High resolution electrolytic lithography, apparatus therefor and resulting products

Abstract

In accordance with the invention, a surface of a substrate is patterned by the steps of providing the substrate, covering the surface with electrolyte, and disposing at least one nanoscale electrode in the electrolyte adjacent the surface. A current is then applied between the electrode and the substrate to electrolyically deposit material on or remove material from the surface. The material is deposited or removed in a pattern dependent on the pattern, movement and shape of the nanoscale electrodes. Apparatus for this process and novel products therefrom are also described.

1 . A method of patterning a surface of a substrate comprising the steps of: 
 providing the substrate;    covering at least a portion of the surface with an electrolyte;    disposing at least one nanoscale electrode in the electrolyte adjacent the surface; and    applying a current between the electrode and the substrate to electrolytically deposit material on or remove material from the substrate surface.    
     
     
         2 . The method of  claim 1  wherein the covering comprises immersing the substrate in an electrolyte bath.  
     
     
         3 . The method of  claim 1  wherein the covering comprises applying a coating layer of electrolyte to the surface.  
     
     
         4 . The method of  claim 1  further comprising the step of moving the electrode to write a pattern.  
     
     
         5 . The method of  claim 1  wherein the nanoscale electrode comprises a nanowire or nanotube.  
     
     
         6 . The method of  claim 1  wherein at the least one nanoscale electrode comprises a plurality of nanowires or nanotubes disposed in a pattern or in a spaced-apart array.  
     
     
         7 . The method of  claim 1  wherein the substrate comprises electrically conductive or semiconductive material.  
     
     
         8 . The method of  claim 1  wherein the at least one nanoscale electrode comprises at least one nanowire or nanotube partially embedded in insulating material.  
     
     
         9 . The method of  claim 1  wherein the at least one nanoscale electrode comprises a plurality of spaced apart nanowires or nanotubes partially embedded in insulating material.  
     
     
         10 . Apparatus for patterning a surface of a substrate comprising: 
 a support for the substrate, the substrate surface in contact with an electrolyte;    one or more nanoscale electrodes;    a movable support for the one or more electrodes, the electrodes attached to the movable support, and the movable support movable to dispose the one or more electrodes in the electrolyte adjacent the surface of the substrate;    a power supply for supplying electrical current; and    a conducting path connecting the substrate and the one or more electrodes to the power supply for supplying current to electrolytically add or remove material on the surface.    
     
     
         11 . The apparatus of  claim 10  wherein the movable support is movable parallel to the surface.  
     
     
         12 . The apparatus of  claim 10  wherein the movable support is movable perpendicular to the surface.  
     
     
         13 . The apparatus of  claim 10  wherein the one or more electrodes comprise one or more nanowires or nanotubes.  
     
     
         14 . The apparatus of  claim 10  wherein the one or more electrodes comprise a plurality of nanowires or nanotubes.  
     
     
         15 . The apparatus of  claim 10  wherein the one or more electrodes comprise a plurality of nanowires or nanotubes disposed in a spaced apart array.  
     
     
         16 . The apparatus of  claim 10  wherein the one or more electrodes comprises one or more nanowires or nanotubes partially embedded in insulating material.  
     
     
         17 . The apparatus of  claim 10  wherein the one or more electrodes comprise a plurality of nanowires or nanotubes disposed in a spaced-apart array and partially embedded in insulating material.  
     
     
         18 . The apparatus of  claim 10  wherein the one or more electrodes comprise a plurality of nanoscale electrodes disposed in a spaced-apart array, and the conducting path connecting the electrodes to the power supply is switchable to permit the connection or disconnection of selected electrodes.  
     
     
         19 . The apparatus of  claim 10  wherein the support for the one or more nanoscale electrodes supports the one or more electrodes in a horizontal orientation.  
     
     
         20 . A method of fabricating an array or pattern spaced-apart nanoscale islands of material on a surface of a surface of a substrate comprising the steps of: 
 providing the substrate;    covering at least a portion the surface with an electrolyte;    disposing in the electrolyte adjacent the surface a plurality of nanoscale electrodes configured in a spaced-apart array or pattern; and    applying current between the electrodes and the substrate to electrolytically deposit the spaced-apart nanoscale islands of material on the surface.    
     
     
         21 . A method of fabricating an array or pattern of spaced-apart nanowires or nanotubes on a surface of a substrate comprising the steps of: 
 providing the substrate;    covering at least a portion of the surface with an electrolyte for depositing a material that is a catalyst for the growth of the nanowires or nanotubes;    disposing in the electrolyte adjacent the surface a plurality of nanoscale electrodes;    applying current between the electrodes and the substrate to electrolytically deposit regions of the catalyst material on the surface in the spaced-apart array or pattern; and    growing the nanotubes or nanowires on the regions of catalyst material.    
     
     
         22 . A method of fabricating a straight or curved line on a surface of a substrate comprising the steps of: 
 providing the substrate;    covering at least a portion of the surface with an electrolyte;    disposing at least one nanoscale electrode in the electrolyte adjacent the surface; and    moving the electrode parallel the surface while applying current between the electrode and the substrate to electrolytically deposit or remove the straight curved line on the substrate surface.    
     
     
         23 . An article comprising: 
 a substrate having a surface; and    disposed on the surface an array or pattern of electrolytically deposited nano islands having effective diameters less than about 500 nanometers.    
     
     
         24 . An article comprising: 
 a substrate having a surface; and    disposed on the surface an array or pattern of electrolytically deposited nanoscale features comprising straight or curved nanolines having widths less than 500 nanometers.    
     
     
         25 . An article comprising: 
 a substrate having a surface; and    disposed on the surface a pattern or array of spaced-apart nanotubes or nanowires grown on a corresponding pattern or array of electrolytically deposited nano islands of catalyst material.    
     
     
         26 . An article according to  claim 25  comprising a magnetic recording medium including an array of spaced-apart magnetic recording elements partially embedded in nonmagnetic material, wherein the spaced-apart nanotubes or nanowires comprise the magnetic recording elements.  
     
     
         27 . An article according to  claim 25  comprising a vacuum tube composed of a cathode, a grid, an anode, and a collector, wherein the spaced-apart array of nanotubes or nanowires comprises the cathode.  
     
     
         28 . An article according to  claim 25  comprising a field emission display including a cathode, a spaced-apart array of electron emitters connected to the substrate, an anode and a phosphor layer, wherein the spaced-apart array of nanotubes or nanowires comprise the electron emitters.  
     
     
         29 . An article according to  claim 25  comprising a plasma display including a plurality of plasma display cells having spaced-apart electrode pairs sealed with ionizable gas, wherein the spaced-apart array of nanotubes or nanowires comprise the spaced-apart electrode pairs.  
     
     
         30 . An article according to  claim 23  comprising a quantum dot device including a substrate supporting a plurality of nanoscale islands of semiconductor material, wherein the electrolytically deposited nanoscale features comprise the semiconductor nanoscale islands.