Method for depositing silicon nanocrystals in hollow fibers

Patent metadata

Field	Value
Publication number	US-9452446-B2
Application number	US-93412509-A
Country	US
Kind code	B2
Filing date	Mar 31, 2009
Priority date	Apr 1, 2008
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A method for depositing a layer of silicon nanocrystals upon the inside surface of hollow fibers is disclosed. In particular, the method includes inserting a hollow glass fiber into a solution of hydrogen silsesquioxane, removing the solvent and heating the hollow glass fiber to a temperature suitable to form silicon nanocrystals, and subsequently cooling the hollow glass fiber.

First claim

The invention claimed is:

1. A method for depositing a layer of silicon nanocrystals on an inner surface of a hollow fiber and obtaining whispering gallery mode resonator, the method comprising:
a) inserting a tip of the hollow fiber into a solution of hydrogen silsesquloxane (HSQ) in a suitable solvent at an angle of about 70° to about 90° between the fiber and the solution, wherein an inner surface of the fiber is coated with the HSQ solution by capillary action;
b) heating the coated hollow fiber in a reducing atmosphere under conditions to remove the solvent;
c) heating the hollow fiber in a reducing atmosphere to a temperature suitable to form silicon nanocrystals; and
d) cooling the hollow fiber to obtain the whispering gallery mode resonator.

2. The method according to claim 1 , wherein the hollow fiber has an inner diameter of about 1 μm to about 250 μm.

3. The method according to claim 2 , wherein the hollow fiber has an inner diameter of 25 μm to about 50 μm.

4. The method according to claim 1 , wherein the hollow fiber is a hollow glass fiber.

5. The method according to claim 4 , wherein the hollow fiber is a hollow fused silica fiber.

6. The method according to claim 1 , wherein the fiber is cleaned and dried prior to insertion into the HSQ solution.

7. The method according to claim 1 , wherein the solvent is methyl isobutyl ketone.

8. The method according to claim 1 , wherein the reducing atmosphere comprises hydrogen gas.

9. The method according to claim 8 , wherein the hydrogen gas is present at a concentration of about 1% to about 10% by weight.

10. The method according to claim 1 , wherein the conditions in b) comprise heating to a suitable temperature of about 250° C. to about 350° C.

11. The method according to claim 10 , wherein the temperature is increased to the suitable temperature at a rate of about 5° C./min.

12. The method according to claim 1 , wherein the conditions in b) comprise heating at the suitable temperature for about 1 hour to about 3 hours.

13. The method according to claim 1 , wherein the suitable temperature in c) is from about 900° C. to about 1300° C.

14. The method according to claim 13 , wherein the suitable temperature in c) is about 1100° C.

15. The method according to claim 13 , wherein the temperature is increased to the suitable temperature in c) at a rate of about 18° C./min.

16. The method according to claim 1 , wherein the hollow fiber is heated at the suitable temperature in c) for about 0.5 hours to about 2 hours.

17. The method according to claim 1 , wherein the hollow glass fiber is cooled in d) to room temperature.

18. The method according to claim 17 , wherein the hollow glass fiber is cooled in d) at a rate of about 2° C./min.

19. The method of claim 1 , wherein the whispering gallery mode resonator is a luminescent whispering gallery mode resonator.

Assignees

• Veinot Jonathan
• Rodriguez Jose Roberto
• Bianucci Pablo
• Meldrum Al
• Univ Alberta

Inventors

• Veinot Jonathan
• Rodriguez Jose Roberto
• Bianucci Pablo
• Meldrum Al

Classifications

• C01B33/023

  by reduction of silica or {free} silica-containing material · CPC title

• Y10T428/13

  Hollow or container type article [e.g., tube, vase, etc.] · CPC title

• C30B7/06

  using non-aqueous solvents · CPC title

• C30B29/605

  Products containing multiple oriented crystallites, e.g. columnar crystallites · CPC title

• Y10T428/1317

  Multilayer [continuous layer] · CPC title