System and method for molecular optical emission

• US 20040061422A1
• Filed: 09/26/2002
• Published: 04/01/2004
• Est. Priority Date: 09/26/2002
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Martel, Richard, Avouris, Phaedon, Misewich, James A., Tsang, James Chen-Hsiang
• Granted Patent: US 7,115,916 B2
• Time in Patent Office: Days
• US Class Current: 313/315
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H10K 10/46 Field-effect transistors, e.g. organic thin-film transistors [OTFT] H10K10/43 takes precedence
• CPC Class Codes: H10K 10/466 Lateral bottom-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 85/221 Carbon nanotubes
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/938 Field effect transistors, FETS, with nanowire- or nanotube-channel region
• CPC Class Codes: Y10S 977/949 Radiation emitter using nanostructure

Abstract

A light emitting device comprises a gate electrode, a channel comprising a molecule for electrically stimulated optical emission, wherein the molecule is disposed within an effective range of the gate electrode, a source coupled to a first end of the channel injecting electrons into the channel, and a drain coupled to a second end of the channel injecting holes into the channel.

Claims

1. A light emitting device comprising:

a gate electrode;

a channel comprising a molecule for electrically stimulated optical emission, wherein the molecule is disposed within an effective range of the gate electrode;

a source coupled to a first end of the channel injecting electrons into the channel; and

a drain coupled to a second end of the channel injecting holes into the channel.

2. The device of claim 1, wherein the molecule is one of a carbon nanotube and a boron-nitride nanotube.

3. The device of claim 1, wherein the gate electrode is formed within a substrate.

4. The device of claim 1, wherein the gate electrode is a substrate.

5. The device of claim 1, wherein the molecule is substantially ambipolar.

6. The device of claim 1, wherein the molecule is a rectifying carbon nanotube.

7. The device of claim 1, wherein the molecule is one of a single-wall nanotube and a multi-wall nanotube.

8. The device of claim 1, wherein a charge density is about between 108 Amps/cm² and 10⁹ Amps/cm².

9. The device of claim 1, wherein a drain voltage is about twice a gate voltage, and the source near ground potential.

10. The device of claim 1, wherein the molecule is substantially undoped.

11. The device of claim 1, wherein the first end of the molecule is n-doped.

12. The device of claim 1, wherein the channel comprises one molecule disposed on the substrate for electrically stimulated optical emission.

13. The device of claim 1, wherein the channel comprises at least two molecules disposed on the substrate for electrically stimulated optical emission.

14. A method for generating light comprising the steps of:

providing a field effect transistor comprising a source, a drain, a gate electrode and a channel comprising a molecule for electrically stimulated optical emission, the molecule having a diameter adapted to generate light of a desired wavelength;

biasing the gate electrode with a gate voltage;

forward-biasing the channel by applying a voltage between the source and the drain; and

recombining an electron and a hole, wherein the recombination generates light of the desired wavelength.

15. The method of claim 14, wherein the channel is one of a carbon nanotube and a boron-nitride nanotube.

16. The method of claim 14, wherein the gate voltage and the voltage applied to the drain produce a charge density across the channel adapted to cause optical emission from the channel.

17. The method of claim 14, wherein the light of the desired wavelength is in a portion of a spectrum including infrared and visible light.

18. The method of claim 14, further comprising the step of doping a first portion of the channel with n-dopants, wherein the first portion of the channel is proximate to the source.

19. The method of claim 14, wherein the channel comprises one molecule disposed on the substrate for electrically stimulated optical emission.

20. The method of claim 14, wherein the channel comprises at least two molecules disposed on the substrate for electrically stimulated optical emission.

21. A light emitting device comprising:

a channel comprising a molecule for electrically stimulated optical emission, wherein the molecule comprises an n-type portion and a p-type portion forming a p-n junction within the molecule;

a source coupled to the p-type portion of the molecule injecting electrons into the molecule; and

a drain coupled to the n-type portion of the molecule injecting holes into the molecule.

22. The device of claim 21, wherein the molecule is one of a carbon nanotube and a boron-nitride nanotube.

23. The device of claim 21, wherein the molecule is forward biased.

24. The device of claim 21, wherein the molecule is intrinsically p-type and an end of the molecule is chemically n-doped to form the n-type portion.

25. A method for generating light comprising the steps of:

providing a two-terminal device comprising a source, a drain and a channel comprising a molecule for electrically stimulated optical emission, wherein the molecule includes an n-type portion and a p-type portion forming a p-n junction within the molecule, wherein the molecule has a diameter adapted to generate light of a desired wavelength;

forward-biasing the molecule by applying a voltage between the source and the drain, wherein the source is coupled to the p-type portion and the drain is coupled to the n-type portion; and

recombining an electron and a hole, wherein the recombination generates light of the desired wavelength.

26. The method of claim 25, wherein the molecule is one of a carbon nanotube and a boron-nitride nanotube.