Large-area nanoenabled macroelectronic substrates and uses therefor
View Patent ↗A method and apparatus for an electronic substrate having a plurality of semiconductor devices is described. A thin film of nanowires is formed on a substrate. The thin film of nanowires is formed to have a sufficient density of nanowires to achieve an operational current level. A plurality of semiconductor regions are defined in the thin film of nanowires. Contacts are formed at the semiconductor device regions to thereby provide electrical connectivity to the plurality of semiconductor devices. Furthermore, various materials for fabricating nanowires, thin films including p-doped nanowires and n-doped nanowires, nanowire heterostructures, light emitting nanowire heterostructures, flow masks for positioning nanowires on substrates, nanowire spraying techniques for depositing nanowires, techniques for reducing or eliminating phonon scattering of electrons in nanowires, and techniques for reducing surface states in nanowires are described.
1. An article comprising:
at least a first and a second population of semiconducting nanowires disposed at distinct, non-overlapping regions from each other on a surface of a substrate, wherein nanowires in the first and second population each comprise a core and one or more shell layers disposed about said core;
at least a first and a second pair of spaced-apart electrical contacts disposed at the distinct regions on the surface of the substrate, wherein at least two nanowires in each of the respective first and second populations of nanowires span and are electrically connected to the electrical contacts of each of the respective first and second pair of electrical contacts; and
wherein nanowires in each of the first and second population of nanowires are substantially oriented in a first direction on the surface of the substrate.
2. The article of claim 1 , wherein the first and second population of nanowires are disposed in a thin film which has an area of greater than 1 mm2 on the surface of the substrate.
3. The article of claim 2 , wherein the thin film has an area of greater than 1 cm2 on the surface of the substrate.
4. The article of claim 2 , wherein the thin film has an area of greater than 10 cm2 on the surface of the substrate.
5. The article of claim 2 , wherein the thin film has an area of greater than 1 m2 on the surface of the substrate.
6. The article of claim 1 , wherein the nanowires in the first population are in substantial parallel alignment with each other.
7. The article of claim 6 , wherein the nanowires in the second population are in substantial parallel alignment with each other.
8. The article of claim 1 , wherein greater than 60% of nanowires in the first and second population of nanowires have a longitudinal axis that is oriented within 30° of the first direction.
9. The article of claim 1 , wherein greater than 75% of nanowires in the first and second population of nanowires have a longitudinal axis that is oriented within 30° of the first direction.
10. The article of claim 1 , wherein greater than 80% of nanowires in the first and second population of nanowires have a longitudinal axis that is oriented within 30° of the first direction.
11. The article of claim 1 , wherein greater than 90% of nanowires in the first and second population of nanowires have a longitudinal axis that is oriented within 30° of the first direction.
12. The article of claim 1 , wherein greater than 50% of nanowires in the first and second population of nanowires have a longitudinal axis that is oriented within 10° of the first direction.
13. The article of claim 1 , wherein said core is made from a compositionally different material than said one or more shell layers.
14. The article of claim 1 , wherein at least one of said one or more shell layers comprises an oxidized shell layer to thereby form a gate dielectric about said core.
15. The article of claim 1 , wherein at least one of said one or more shell layers comprises SiO2 and said core comprises Si.
16. The article of claim 1 , wherein the substrate comprises a flexible substrate.
17. The article of claim 1 , wherein the first and second population of nanowires comprises nanowires selected from the Group II-VI semiconductors, the Group III-V semiconductors and the Group IV semiconductors.