Methods of nanotube films and articles
Nanotube films and articles and methods of making the same. A conductive article includes an aggregate of nanotube segments which contact other nanotube segments to define a plurality of conductive pathways along the article. Segments may have different lengths and may be shorter than the article. Conductive articles may be made on a substrate by forming a nanotube fabric on the substrate, and defining within the fabric a pattern corresponding to the conductive article. The nanotube fabric may be grown on the substrate using a catalyst, such as a gas phase a metallic gas phase catalyst. The nanotube fabric may be formed by depositing a solution of suspended nanotubes on the substrate, which may be spun to create a spin-coating of the solution. The solution may be deposited by dipping the substrate into the solution. The nanotube fabric may be formed by spraying an aerosol having nanotubes onto the substrate.
1. A method of making a non-woven film of conductive nanotubes, the method comprising providing a substrate having a substantially planar top surface defining a major surface of the substrate, the major surface of the substrate comprising a patterned array of conductive elements, introducing a vapor-phase catalyst to foster growth of nanotubes, and introducing a carbon source to grow a layer of nanotubes that are disposed on and substantially parallel to the major surface of the substrate.
2. The method of claim 1 wherein the vapor-phase catalyst is a metallocene.
3. The method of claim 1 wherein the nanotubes include single-walled carbon nanotubes.
4. The method of claim 1 wherein the nanotubes include multi-walled carbon nanotubes.
5. The method of claim 1 , wherein the major surface of the substrate further comprises an ordered array of insulative elements.
6. The method of claim 1 , wherein the major surface of the substrate further comprises an ordered array of sacrificial material.
7. The method of claim 6 , further comprising removing the sacrificial material after introducing the carbon source.
8. The method of claim 1 , wherein the conductive elements are substantially parallel to one another.
9. A method of making conductive articles, comprising:
providing a substrate, the substrate including a patterned array of conductive elements;
providing a patterned layer of material;
providing a catalyst that fosters growth of nanotubes;
providing a carbon source, so as to grow randomly oriented nanotubes substantially parallel to a major surface of the substrate in regions defined by the pattern and over the patterned array of conductive elements.
10. The method of claim 9 wherein the carbon source and the catalyst are introduced in a single act.
11. The method of claim 9 wherein the carbon source and the catalyst are introduced as separate acts.
12. The method of claim 9 wherein the patterned layer of material is an insulator or a semiconductor and wherein the nanotubes grow over the patterned material.
13. The method of claim 9 wherein the patterned layer is a patterned metal layer and wherein the nanotubes grow in areas other than the patterned metal layer.
14. The method of claim 9 , wherein the substrate further comprises an ordered array of insulative elements.
15. The method of claim 9 , wherein the substrate further comprises an ordered array of sacrificial material.
16. The method of claim 15 , further comprising removing the sacrificial material after introducing the carbon source.
17. The method of claim 9 , wherein the conductive elements are substantially parallel to one another.