Orthogonal processing of organic materials used in electronic and electrical devices
An orthogonal process for photolithographic patterning organic structures is disclosed. The disclosed process utilizes fluorinated solvents or supercritical CO 2 as the solvent so that the performance of the organic conductors and semiconductors would not be adversely affected by other aggressive solvent. One disclosed method may also utilize a fluorinated photoresist together with the HFE solvent, but other fluorinated solvents can be used. In one embodiment, the fluorinated photoresist is a resorcinarene, but various fluorinated polymer photoresists and fluorinated molecular glass photoresists can be used as well. For example, a copolymer perfluorodecyl methacrylate (FDMA) and 2-nitrobenzyl methacrylate (NBMA) is a suitable orthogonal fluorinated photoresist for use with fluorinated solvents and supercritical carbon dioxide in a photolithography process. The combination of the fluorinated photoresist and the fluorinated solvent provides a robust, orthogonal process that is yet to be achieved by methods or devices known in the art.
1. A method for patterning a device, the method comprising:
coating a substrate with a layer of fluorinated photoresist material;
selectively exposing portions of the layer of fluorinated photoresist material to radiation;
contacting the layer of fluorinated photoresist material with a first fluorinated solvent to develop a patterned fluorinated photoresist; and
removing the patterned fluorinated photoresist with a second fluorinated solvent that is the same as or different from the first fluorinated solvent.
2. The method of claim 1 , wherein the first fluorinated solvent comprises a hydrofluoroether.
3. The method of claim 1 , wherein the second fluorinated solvent comprises a hydrofluoroether.
4. The method of claim 1 , wherein both the first and second fluorinated solvents comprise a hydrofluoroether.
5. The method of claim 1 , wherein the device is at least part of an organic thin film transistor, an organic light-emitting diode, an organic photovoltaic, or an organic sensor.
6. The method of claim 1 , wherein the layer of fluorinated photoresist material is coated from a composition comprising a fluorinated coating solvent.
7. The method of claim 6 , wherein the fluorinated coating solvent comprises at least one hydrofluoroether.
8. The method of claim 1 , wherein the fluorinated photoresist material comprises a photo-acid generator.
9. The method of claim 8 , wherein the photo-acid generator is non-ionic.
10. The method of claim 1 , wherein the fluorinated photoresist material is configured to form a negative tone image.
11. A method for patterning a device, the method comprising:
coating a substrate with a layer of fluorinated photoresist material, wherein the substrate comprises one or more layers comprising one or more thin films of at least one active organic electronic material;
selectively exposing portions of the layer of fluorinated photoresist material to radiation; and
contacting the layer of fluorinated photoresist material with a fluorinated solvent to develop a patterned fluorinated photoresist.
12. The method of claim 11 , wherein at least one of the active organic electronic material comprises a semiconducting polymer or a small molecule.
13. The method of claim 11 , wherein the fluorinated solvent comprises a hydrofluoroether.
14. The method of claim 11 , wherein the device is at least part of an organic thin film transistor, an organic light-emitting diode, an organic photovoltaic, or an organic sensor.
15. The method of claim 11 , wherein the layer of fluorinated photoresist material is coated from a composition comprising a fluorinated coating solvent.
16. The method of claim 15 , wherein the fluorinated coating solvent comprises at least one hydrofluoroether.
17. The method of claim 11 , wherein the fluorinated photoresist material comprises a photo-acid generator.
18. The method of claim 17 , wherein the photo-acid generator is non-ionic.
19. The method of claim 11 , wherein the fluorinated photoresist material is configured to form a negative tone image.