Structures for interdigitated finger co-extrusion

Abstract

A device has isolated structures on a substrate, the isolated structures formed of a first material, the structures extending vertically from the substrate, and a second material on the substrate surrounding the isolated structures. A method of forming isolated structures includes depositing a first material and a second material on a substrate using a co-extrusion print head by applying pressure to the first material and the second material, periodically reducing the pressure applied to the first material to stop deposition of the first material while continuing to apply pressure to the second material to form isolated structures of the first material extending vertically from the substrate surrounded by the second material on the substrate, and removing the second material to leave isolated structures on the substrate.

What is claimed is: 
     
         1 . A device, comprising:
 isolated structures on a substrate, the isolated structures formed of a first material, the structures extending vertically from the substrate; and   a second material on the substrate surrounding the isolated structures.   
     
     
         2 . The device as clamed in  claim 1 , wherein the first material comprises a binder and a first active material. 
     
     
         3 . The device as clamed in  claim 2 , wherein the second material has a lower density than the first material. 
     
     
         4 . The device as clamed in  claim 2 , wherein the second material is a more dilute solution of the first material. 
     
     
         5 . The device as clamed in  claim 1 , wherein the second material comprises an electrolyte. 
     
     
         6 . The device as clamed in  claim 1 , wherein the isolated structures have a trapezoidal cross section. 
     
     
         7 . The device as clamed in  claim 1 , wherein the second material comprises a residue of a sacrificial material. 
     
     
         8 . A method of forming isolated structures, comprising:
 depositing a first material and a second material on a substrate using a co-extrusion print head by applying pressure to the first material and the second material;   periodically reducing the pressure applied to the first material to stop deposition of the first material while continuing to apply pressure to the second material to form isolated structures of the first material extending vertically from the substrate surrounded by the second material on the substrate; and   removing the second material to leave isolated structures on the substrate.   
     
     
         9 . The method as clamed in  claim 8 , wherein depositing the first material comprises depositing the first material consisting of a solvent, a binder, and a first active material. 
     
     
         10 . The method as clamed in  claim 8 , wherein depositing the second material comprises depositing the second material consisting of a solvent and a second active material. 
     
     
         11 . The method as clamed in  claim 10 , wherein the second material has a lower density than the first material. 
     
     
         12 . The method as clamed in  claim 10 , wherein the second material is a more dilute solution of the first material. 
     
     
         13 . The method as clamed in  claim 11 , wherein the first material comprises one or more selected from the group consisting of: lithium cobalt oxide (LCO), lithium nickel cobalt manganese (NCM), lithium nickel cobalt aluminum oxide (NCA), lithium manganese oxide (LMO), lithium titanate (LTO), and mixtures thereof. 
     
     
         14 . The method as clamed in  claim 8 , wherein removing comprises drying that leaves a residue on surfaces of the isolated structures and the substrate. 
     
     
         15 . The method as clamed in  claim 8 , wherein first material and the second material have matched viscosities. 
     
     
         16 . The method as clamed in  claim 8 , wherein the first material comprises a conductive material. 
     
     
         17 . The method as clamed in  claim 8 , wherein the first material comprises a non-conducting polymer. 
     
     
         18 . The method as clamed in  claim 17 , further comprising using the isolated structures on the substrate as an etch mask. 
     
     
         19 . The method as clamed in  claim 18 , further comprising using the isolated structures on the substrate as an interconnect.