ORGANIC OPTOELECTRONIC DEVICE ELECTRODES WITH NANOTUBES
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.
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/□.