Electronic devices

Abstract

A method for forming an electronic device having a multilayer structure, comprising: embossing a surface of a substrate so as to depress first and second regions of the substrate relative to at least a third region of the substrate; depositing conductive or semiconductive material from solution onto the first and second regions of the substrate so as to form a first electrode on the first region and a second electrode on the second region, wherein the electrodes are electrically insulated from each other by the third region.

What is claimed is: 
     
         1 . A method for solution deposition of at least one pattern of material on a substrate comprising:
 (a) depositing onto a surface of a substrate an intermediate layer, wherein the substrate is one of hydrophobic and hydrophilic and the intermediate layer is the other of hydrophilic and hydrophobic;   (b) depositing a sacrificial layer onto a surface of the intermediate layer;   (c) embossing the sacrificial layer so as to define at least one depressed region and at least one raised region;   (d) etching the sacrificial layer and the intermediate layer so as to reveal the surface of the substrate in the areas defined by the one or more depressed regions, and leaving the intermediate layer in the areas defined by the one or more raised regions;   (e) removing any remainder of the sacrificial layer in the areas defined by the one or more raised regions; and   (f) using the etched intermediate layer to control the deposition of a solution of said material on to the substrate.   
     
     
         2 . A method as claimed in  claim 1 , wherein said at least one pattern of material is at least one conducting electrode. 
     
     
         3 . A method for solution deposition of at least one pattern of material on a substrate comprising:
 (a) depositing a sacrificial layer onto a surface of the substrate;   (b) embossing the sacrificial layer so as to define at least one depressed region and at least one raised region;   (c) etching the sacrificial layer so as to reveal the surface of the substrate in the areas defined by the one or more depressed regions, and leaving a mask layer in the areas defined by the one or more raised regions;   (d) modifying the surface energy of the substrate in the regions left exposed by the mask layer;   (e) removing the mask layer in a second etching step, which has substantially no further effect on the surface energy of the substrate, so as to leave a surface energy pattern on the surface of the substrate conformal to the initial embossing; and   (f) using the surface energy pattern to control the deposition of a solution of said material on to the substrate.   
     
     
         4 . A method as described in  claim 3 , wherein modifying the surface energy of the substrate comprises exposing the substrate to a vapour of a self-assembling monolayer. 
     
     
         5 . A method as described in  claim 3 , wherein modifying the surface energy of the substrate comprises exposing the substrate to an oxygen plasma or ultra violet/ozone surface treatment 
     
     
         6 . A method as described in  claim 3 , wherein modifying the surface energy of the substrate comprises exposing the substrate to a carbon tetrafluoride plasma treatment. 
     
     
         7 . A method as claimed in  claim 3 , wherein removing the mask layer such that the surface energy of the modified regions is unchanged comprises washing in a solvent in which the mask layer is soluble, but the substrate is insoluble. 
     
     
         8 . A method as claimed in  claim 4 , wherein the self-assembling monolayer is capable of reacting with a functional group present on the substrate surface. 
     
     
         9 . A method as claimed in  claim 8 , further comprising treating the surface of the substrate so as to increase the number of functional groups on the surface of the substrate.