Silicon nanoparticle nanotubes and method for making the same

• US 7,429,369 B2
• Filed: 06/09/2004
• Issued: 09/30/2008
• Est. Priority Date: 10/22/1999
• Status: Expired due to Fees

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Nayfeh, Munir H., Chaieb, Sahraoui
• Primary Examiner(s): Kim, Vickie
• Assistant Examiner(s): Smith, Jennifer A
• Application Number:
  US10/864,072
• Publication Number:
  US 20080187480A1
• Time in Patent Office: 1,574 Days
• Field of Search: 423/350, 423/348, 423/349, 385/142, 438/753, 438/769, 438/771, 438/782
• US Class Current: 423/348
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01B 33/02 Silicon forming single crystals or homogeneous polycrystalline material with defined structure C30B
• CPC Class Codes: C30B 29/06 Silicon
• CPC Class Codes: C30B 29/602 Nanotubes
• CPC Class Codes: G02B 6/02 Optical fibres with cladding with or without a coating
• CPC Class Codes: G02B 6/10 of the optical waveguide type G02B6/02, G02B6/24 take precedence; devices or arrangements for the control of light by electric, magnetic, electro-magnetic or acoustic means G02F1/00; transferring the modulation of modulated light G02F2/00; optical logic elements G02F3/00; optical analogue/digital converters G02F7/00
• CPC Class Codes: H01S 3/163 characterised by a crystal matrix
• CPC Class Codes: H01S 5/041 Optical pumping
• CPC Class Codes: H01S 5/10 Construction or shape of the optical resonator , e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region H01S5/20 takes precedence
• CPC Class Codes: H01S 5/30 Structure or shape of the active region; Materials used for the active region
• CPC Class Codes: H01S 5/3031 Si

Abstract

A relatively thick electrode is positioned opposite the surface of a substrate/second electrode. The electrode and the substrate surface are both contacted by a solution including silicon nanoparticles. The substrate surface is completely immersed in the solution in a manner such that there is not an air/solution interface and there is no meniscus at the substrate surface. Application of electrical potential between the electrode and the substrate creates a film of silicon nanoparticles on the substrate. Drying of the film induces the film to roll up and form a silicon nanoparticle nanotube material. A film may be subdivided into an array of identical portions, and the identical portions will roll into identical tubes having same length and diameter. A silicon nanoparticle nanotube material of the invention includes nanotubes formed of silicon nanoparticles.

Claims

1. A method for forming silicon nanoparticle nanotubes, the method comprising steps of:

disposing a conductive or semiconductive substrate in a solution including a dispersion of silicon nanoparticles, said disposing being done in a manner to avoid a meniscus being formed on a surface of the substrate;

disposing a thick electrode opposite the surface of the substrate;

applying electrical potential between the substrate and the thick electrode;

maintaining the electrical potential between the substrate and the thick electrode to form a thin film of silicon nanoparticles on the substrate; and

drying the thin film to induce it to roll into a silicon nanoparticle nanotube;

wherein the area and thickness of the thin film is such that a diameter of the silicon nanoparticle nanotube is at least about 100 times greater than the thickness of the thin film.

2. The method of claim 1, wherein the substrate comprises a silicon wafer.

3. The method of claim 1, wherein said step of disposing a conductive or semiconductive substrate comprises horizontally disposing the surface of the substrate at the bottom of an electrochemical etching cell including the solution.

4. The method of claim 3, wherein the thick electrode comprises a metal rod.

5. The method of claim 4, wherein the metal rod has a diameter of at least about 5 nm.

6. The method of claim 4, wherein said step of disposing a thick electrode comprises disposing the metal rod substantially perpendicular to the surface of the substrate.

7. The method of claim 1, further comprising a step of subdividing the thin film prior to said step of drying.

8. The method of claim 7, wherein said step of subdividing is conducted to divide the thin film into uniform regions, and the method forms a plurality of silicon nanoparticle nanotubes having the same dimensions.

9. The method of claim 8, further comprising a step of bundling formed silicon nanoparticle nanotubes together.

10. Silicon nanoparticle material, comprising a flexible nanotube formed of silicon nanoparticles.

11. The material of claim 10, wherein the flexible nanotube comprises 1 nm silicon nanoparticles.

12. The material of claim 10, wherein the flexible nanotube comprises an Silicon-Oxygen superlattice structure.

13. The material of claim 10, comprising a plurality of flexible nanotubes formed of silicon nanoparticles.

14. The material of claim 13, wherein said plurality of flexible nanotubes are bundled together.