Carbon-based semiconductors

• US 20130082234A1
• Filed: 10/03/2012
• Published: 04/04/2013
• Est. Priority Date: 10/03/2011
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Inventors: Bao, Zhenan, Vosgueritchian, Michael, Ramuz, Marc
• Granted Patent: US 8,866,265 B2
• Time in Patent Office: Days
• US Class Current: 257/9
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H10K 30/20 comprising organic-organic junctions, e.g. donor-acceptor junctions
• CPC Class Codes: H10K 30/50 Photovoltaic [PV] devices
• CPC Class Codes: H10K 30/821 comprising carbon nanotubes
• CPC Class Codes: H10K 85/211 Fullerenes, e.g. C60
• CPC Class Codes: H10K 85/221 Carbon nanotubes
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

All-carbon-based semiconductor devices are provided. In accordance with an example embodiment, an apparatus includes n-type and p-type carbon-based semiconductor material that form a p-n junction, which are respectively coupled to electrodes having a carbon allotrope. A first one of electrodes is connected to the n-type material and a second one of the electrodes is connected to the p-type material, and collect charge presented at the p-n junction.

Claims

1. An apparatus comprising:

a carbon-based semiconductor material including n-type and p-type materials that form a p-n junction; and

first and second electrodes including a carbon allotrope, the first electrode being connected to the n-type material and the second electrode being connected to the p-type material, the electrodes being configured and arranged to collect charge generated at the p-n junction.

2. The apparatus of claim 1, wherein the first electrode includes carbon nanotubes doped with an n-type dopant, and the second electrode includes ozone-plasma-treated reduced graphene oxide.

3. The apparatus of claim 1, wherein the carbon-based semiconductor material is stacked vertically between the first and second electrodes, the p-n junction is configured and arranged to exhibit a photovoltaic effect, and at least one of the electrodes is configured and arranged to pass light to the carbon-based semiconductor material for generating the charges.

4. The apparatus of claim 3, wherein the carbon-based semiconductor material includes n-type C60 material and p-type semiconducting carbon nanotubes.

5. The apparatus of claim 1, wherein the first electrode includes carbon nanotubes doped with an n-type dopant, and the second electrode includes a reduced graphene oxide sheet.

6. The apparatus of claim 1, wherein the first electrode includes at least one of doped carbon nanotubes, doped graphene and doped C60.

7. The apparatus of claim 1, wherein the second electrode includes at least one of graphene and conductive carbon nanotubes.

8. The apparatus of claim 1, wherein the first electrode includes carbon nanotubes, and the second electrode includes reduced graphene oxide.

9. The apparatus of claim 1, wherein the first electrode includes carbon nanotubes doped with an n-type dopant.

10. The apparatus of claim 1, wherein the second electrode includes reduced graphene oxide.

11. The apparatus of claim 1, wherein the second electrode includes ozone-plasma-treated reduced graphene oxide.

12. The apparatus of claim 1, wherein the second electrode includes conductive carbon nanotubes.

13. The apparatus of claim 1, wherein the carbon-based semiconductor material is configured to generate the charge by dissociating excitons generated at the p-n junction in response to light incident upon the carbon-based semiconductor material.

14. The apparatus of claim 1, wherein the carbon-based semiconductor material and the electrodes consist of a carbon-based material.

15. The apparatus of claim 1, wherein the carbon-based semiconductor material includes a plurality of single-walled carbon nanotubes including first and second types of nanotubes having different light absorption characteristics, the first type of nanotubes being configured and arranged to absorb more light energy than the second type of nanotubes under a first light condition, and the second type of nanotubes being configured and arranged to absorb more light energy than the first type of nanotubes under a second light condition that is different than the first light condition.

16. A photovoltaic apparatus comprising:

an anode having an ozone-plasma-treated reduced graphene oxide sheet;

a cathode having n-doped carbon nanotubes; and

a carbon-based semiconductor material separating the anode and cathode and including an n-type material including n-type fullerene connected to the cathode, and a p-type material including p-type semiconducting carbon nanotubes, the n-type material and p-type material a forming p-n junction configured and arranged to generate charge via a photovoltaic effect in response to light passed via one of the anode and cathode, the anode and cathode being configured and arranged to pass the generated charge.

17. The apparatus of claim 16, wherein the ozone-plasma-treated reduced graphene oxide sheet is configured and arranged to facilitate a work-function increase in the apparatus of at least 5%, relative to such a reduced graphene oxide sheet not exhibiting ozone-plasma-treatment characteristics.

18. A method comprising:

forming a first electrode including a carbon allotrope;

forming a carbon-based semiconductor material including n-type and p-type materials that form a p-n junction that exhibits a photovoltaic effect, the n-type material being connected to the first electrode; and

forming a second electrode including a carbon allotrope connected to the p-type material, the first and second electrodes being configured and arranged to collect charge generated at the p-n junction.

19. The method of claim 18, wherein forming the first electrode includes forming an anode by treating a reduced graphene oxide sheet with ozone-plasma.

20. The method of claim 19, wherein treating the reduced graphene oxide sheet with ozone-plasma includes increasing the work-function of the reduced graphene oxide sheet by treating the reduced graphene oxide sheet with ozone-plasma during multiple periods of time between which the reduced graphene oxide sheet is not treated with the ozone-plasma.

21. The method of claim 18, wherein forming the carbon-based semiconductor material includes forming p-type semiconducting carbon nanotubes on the first electrode and forming n-type fullerene on the p-type material to form the p-n junction.

22. The method of claim 18, wherein forming the second electrode includes forming a cathode having n-doped carbon nanotubes on the n-type material.

23. The method of claim 18, wherein forming the second electrode includes spray-coating a solution of single-walled carbon nanotubes on a substrate and doping the single-walled carbon nanotubes using a molecular n-type dopant.

24. The method of claim 18, wherein forming the carbon-based semiconductor material includes forming first and second types of nanotubes having different light absorption characteristics, the first type of nanotubes being configured and arranged to absorb more light energy than the second type of nanotubes under a first light condition, and the second type of nanotubes being configured and arranged to absorb more light energy than the first type of nanotubes under a second light condition that is different than the first light condition.