Selective nanotube formation and related devices

1. A method for manufacturing nanotubes, the method comprising:

treating a substrate surface to respectively interact with semiconducting-type nanotubes and metallic-type nanotubes at different substrate-nanotube interaction strengths;

applying, to the treated surface, a nanotube solution including semiconducting-type nanotubes and metallic-type nanotubes dispersed in a solvent; and

for at least a portion of the substrate surface, mechanically removing a substantial portion of one of the types of nanotubes for which the substrate-nanotube interaction strength is lower, relative to the substrate-nanotube interaction strength for another one of the types of nanotubes;

wherein treating a substrate surface includes

selectively functionalizing semiconductor regions of the surface to exhibit higher chemical interaction with semiconducting nanotubes, relative to interaction with metallic nanotubes, and

selectively functionalizing conductor regions of the surface to exhibit higher chemical interaction with metallic nanotubes, relative to interaction with semiconducting nanotubes, and

wherein the step of mechanically removing includes removing metallic-type nanotubes from the semiconductor regions and removing semiconducting-type nanotubes from the conductor regions.

2. The method of claim 1 , wherein the step of mechanically removing includes applying a mechanical force that is sufficient to remove the substantial portion of said one of the types of nanotubes, and while being insufficient to remove a significant number of the said other one of the types of nanotubes.

3. The method of claim 1 , wherein

the step of applying includes spinning the substrate prior to and during the application of the nanotube solution to the treated surface, and

the step of mechanically removing includes spinning the substrate to apply mechanical shear to said one of the types of nanotubes.

4. The method of claim 1 , wherein the step of mechanically removing includes spinning the substrate to apply a mechanical shearing force that is sufficient to remove the substantial portion of said one of the types of nanotubes, and while being insufficient to remove a significant number of the said other one of the types of nanotubes.

5. The method of claim 1 , wherein treating a substrate surface includes functionalizing the surface with a chemical group to set characteristics of a subsequently-applied nanotube film, the characteristics including at least one of alignment, density, chirality and connectivity of the nanotubes in the film.

6. A method for manufacturing nanotubes, the method comprising:

treating a substrate surface to respectively interact with semiconducting-type nanotubes and metallic-type nanotubes at different substrate-nanotube interaction strengths;

applying, to the treated surface, a nanotube solution including semiconducting-type nanotubes and metallic-type nanotubes dispersed in a solvent; and

for at least a portion of the substrate surface, mechanically removing a substantial portion of one of the types of nanotubes for which the substrate-nanotube interaction strength is lower, relative to the substrate-nanotube interaction strength for another one of the types of nanotubes;

wherein treating a substrate surface includes

selectively functionalizing semiconductor regions of the surface to exhibit higher chemical interaction with semiconducting nanotubes, relative to interaction with metallic nanotubes, and

selectively functionalizing conductor regions of the surface to exhibit higher chemical interaction with metallic nanotubes, relative to interaction with semiconducting nanotubes,

wherein the step of mechanically removing includes removing metallic-type nanotubes from the semiconductor regions and removing semiconducting-type nanotubes from the conductor regions; and

wherein the step of applying includes spinning the substrate surface, while applying the nanotube solution thereto, at a rotational speed that sets a selected alignment of nanotubes in the solution.

7. The method of claim 1 , wherein the step of applying includes forming a monolayer film of nanotubes.

8. The method of claim 1 , wherein

the step of applying includes coating the surface of the substrate with a layer of the nanotube solution, and

the step of mechanically removing includes mechanically removing the substantial portion of one of the types of nanotubes after the surface has been coated.

9. The method of claim 1 , wherein the step of treating a substrate surface includes

selecting one of either semiconducting-type or metallic-type nanotubes according to an intended use of the substrate, and

treating the substrate surface to interact more strongly with the selected one of the types nanotubes, relative to the other one of the types of nanotubes.

10. The method of claim 1 , wherein applying a nanotube solution includes applying nanotubes dispersed in a solution that is substantially devoid of surfactants.

11. The method of claim 1 , wherein applying a nanotube solution includes applying nanotubes dispersed in a solution that facilitates nanotube interaction directly with the treated substrate surface.

12. The method of claim 1 , wherein the step of mechanically removing includes applying a linear shear force to remove a substantial portion of the one of the types of nanotubes.

13. A method for manufacturing involving spin-coating a nanotube film onto a substrate, the method comprising:

treating an upper surface of the substrate to respectively interact with semiconducting-type nanotubes and with metallic-type nanotubes at different substrate-nanotube interaction strengths;

spinning the substrate to apply a shearing force that is sufficient to overcome the substrate-nanotube interaction of a first one of the types of nanotubes, and that is insufficient to overcome the substrate-nanotube interaction of the other one of the types of nanotubes; and

while the substrate is spinning,

applying, to the treated surface, a nanotube solution including semiconducting-type nanotubes and metallic-type nanotubes, and

using the shearing force to remove a substantial portion of the first type of nanotubes.

14. The method of claim 13 , wherein using the shearing force to remove a substantial portion of the first type of nanotubes includes removing at least about 80% of the one of the types of nanotubes.

15. The method of claim 13 , wherein treating an upper surface of the substrate includes forming a surface having at least some regions patterned with a material that interact strongly with semiconducting nanotubes and other regions patterned with at least one of: a material that exhibits weak interactions with semiconducting nanotubes, a material that interacts more strongly with metallic nanotubes relative to interactions with semiconducting nanotubes, and a material that does not exhibit relative selectivity to semiconducting or metallic nanotubes.

16. A method for manufacturing, comprising:

providing a treated substrate surface; using the treated substrate surface that respectively interacts with semiconducting-type nanotubes and with metallic-type nanotubes at different substrate-nanotube interaction strengths to separate, by mechanically removing, the semiconducting-type nanotubes from the metallic-type nanotubes dispersed in a solvent and wherein the treated substrate surface includes selectively functionalized semiconductor regions to exhibit higher chemical interaction with the semiconducting nanotubes, relative to interaction with the metallic nanotubes, and selectively functionalized conductor regions to exhibit higher chemical interaction with metallic nanotubes, relative to interaction with semiconducting nanotubes;

providing the semiconducting-type nanotubes separated from the metallic-type nanotubes.

17. The method of claim 16 , further including mechanically removing a substantial portion of one of the types of nanotubes for which the substrate-nanotube interaction strength is lower, relative to the substrate-nanotube interaction strength for the other one of the types of nanotubes.

18. A method for manufacturing, comprising:

treating a substrate surface to respectively interact with different nanotube types at different substrate-nanotube interaction strengths;

applying, to the treated surface, a nanotube solution including different types of nanotubes dispersed in a solvent, the different types of nanotubes including metallic-type nanotubes and semiconducting-type nanotubes; and

for at least a portion of the substrate surface, mechanically removing a substantial portion that is at least 70% of one of the types of applied nanotubes for which the substrate-nanotube interaction strength is lower, relative to the substrate-nanotube interaction strength for another one of the types of applied nanotubes, wherein the step of mechanically removing includes removing metallic-type nanotubes from semiconductor regions and removing semiconducting-type nanotubes from conductor regions, and wherein the treated substrate surface includes selectively functionalized semiconductor regions to exhibit higher chemical interaction with semiconducting nanotubes, relative to interaction with metallic nanotubes, and selectively functionalized conductor regions to exhibit higher chemical interaction with metallic nanotubes, relative to interaction with semiconducting nanotubes.

19. The method of claim 18 , wherein treating a substrate surface includes functionalizing the surface with a chemical group to set characteristics of a subsequently-applied nanotube film, the characteristics including at least one of alignment and density of the nanotubes in the film.