Organic optoelectronic device electrodes with nanotubes

Abstract

An electrode for use in an organic optoelectronic device is provided. The electrode includes a thin film of single-wall carbon nanotubes. The film may be deposited on a substrate of the device by using an elastomeric stamp. The film may be enhanced by spin-coating a smoothing layer on the film and/or doping the film to enhance conductivity. Electrodes according to the present invention may have conductivities, transparencies, and other features comparable to other materials typically used as electrodes in optoelectronic devices.

What is claimed is: 
     
         1 . A method of manufacturing an optoelectronic device, comprising:
 preparing a suspension of nanotubes;   filtering the suspension to form a thin film of nanotubes on a filtration membrane; and   depositing the thin film over a substrate.   
     
     
         2 . The method of  claim 1 , wherein depositing the thin film of nanotubes over the substrate comprises:
 transferring the thin film from the filtration membrane to an elastomeric stamp; and   pressing the elastomeric stamp onto the substrate to transfer the thin film from the elastomeric stamp to the substrate.   
     
     
         3 . The method of  claim 1 , wherein preparing the suspension of nanotubes comprises agitating the suspension. 
     
     
         4 . The method of  claim 3 , wherein the suspension is agitated ultrasonically. 
     
     
         5 . The method of  claim 1 , wherein preparing the suspension comprises functionalizing the nanotubes in the suspension. 
     
     
         6 . The method of  claim 1 , wherein the nanotubes are arc discharge nanotubes. 
     
     
         7 . The method of  claim 1 , further comprising spin-coating a smoothing layer on the thin film. 
     
     
         8 . The method of  claim 7 , wherein the thin film is smoothed to an rms roughness of not more than 3.1 nm. 
     
     
         9 . The method of  claim 1 , further comprising doping the thin film. 
     
     
         10 . The method of  claim 9 , wherein the thin film is doped with a conductivity-enhancing dopant to a resistance of not more than 160 Ω/□. 
     
     
         11 . The method of  claim 1 , further comprising patterning the thin film to form a plurality of pixels. 
     
     
         12 . The method of  claim 1 , further comprising depositing an organic layer over the substrate. 
     
     
         13 . The method of  claim 12 , further comprising depositing an electrode over the organic layer. 
     
     
         14 . The method of  claim 12 , wherein the organic layer is an emissive layer. 
     
     
         15 . The method of  claim 12 , wherein the organic layer is a photoactive layer. 
     
     
         16 . A device comprising:
 a first electrode comprising a film of nanotubes;   a smoothing layer disposed on the film of nanotubes;   a second electrode; and   an organic layer disposed between and in electrical contact with the first electrode and the second electrode.   
     
     
         17 . The device of  claim 16 , wherein the first electrode has an rms roughness of not more than 3.1 nm. 
     
     
         18 . The device of  claim 16 , wherein the first electrode has a sheet resistance of not more than 500 Ω/□. 
     
     
         19 . The device of  claim 18 , wherein the first electrode has a transparency of at least 75%. 
     
     
         20 . The device of  claim 16 , wherein the first electrode has a sheet resistance of not more than 160 Ω/□ and a transparency of at least 87%. 
     
     
         21 . The device of  claim 16 , wherein the nanotubes are single-walled nanotubes. 
     
     
         22 . The device of  claim 16 , wherein the organic layer comprises an organic emissive material. 
     
     
         23 . The device of  claim 16 , wherein the organic layer comprises an organic photosensitive donor-acceptor heterojunction. 
     
     
         24 . The device of  claim 16 , wherein the film of nanotubes is doped. 
     
     
         25 . The device of  claim 24 , wherein the film of nanotubes is doped with SOCl 2 . 
     
     
         26 . The device of  claim 16 , wherein the smoothing layer is poly (3,4-ethylenedioxythiophene). 
     
     
         27 . The device of  claim 16 , wherein the first electrode has an rms roughness of not more than 3.1 nm and a sheet resistance of not more than 500 Ω/□. 
     
     
         28 . The device of  claim 16 , wherein the first electrode has an rms roughness of not more than 3.1 nm and a sheet resistance of not more than 160 Ω/□.