Ceramic composition having dispersion of nano-particles therein and methods of fabricating same

• US 9,269,844 B2
• Filed: 12/03/2013
• Issued: 02/23/2016
• Est. Priority Date: 12/13/2012
• Status: Active Grant

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Pacific Light Technologies Corp. (Ams-Osram AG)
• Inventors: Kurtin, Juanita N., Masson, Georgeta
• Primary Examiner(s): Loewe, Robert S
• Application Number:
  US14/095,825
• Publication Number:
  US 20140166945A1
• Time in Patent Office: 812 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/883 with zinc or cadmium
• CPC Class Codes: H01L 31/0264 Inorganic materials
• CPC Class Codes: H01L 31/055 where light is absorbed and re-emitted at a different wavelength by the optical element directly associated or integrated with the PV cell, e.g. by using luminescent material, fluorescent concentrators or up-conversion arrangements
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: Y02E 10/52 PV systems with concentrators
• CPC Class Codes: Y10S 977/774 Exhibiting three-dimensional carrier confinement, e.g. quantum dots
• CPC Class Codes: Y10S 977/779 Possessing nanosized particles, powders, flakes, or clusters other than simple atomic impurity doping

Abstract

Ceramic compositions having a dispersion of nano-particles therein and methods of fabricating ceramic compositions having a dispersion of nano-particles therein are described. In an example, a method of forming a composition having a dispersion of nano-particles therein includes forming a mixture of semiconductor nano-particles and ceramic precursor molecules. A ceramic matrix is formed from the ceramic precursor molecules. The ceramic matrix includes a dispersion of the semiconductor nano-particles therein. In another example, a composition includes a medium including ceramic precursor molecules. The medium is a liquid or gel at 25 degrees Celsius. A plurality of semiconductor nano-particles is suspended in the medium.

Claims

1. A composition, comprising:

a medium comprising ceramic precursor molecules, the medium a liquid or gel at 25 degrees Celsius, wherein the ceramic precursor molecules are thermal or ultra-violet (UV) labile β

-chloropolysilsequioxane molecules, and wherein the medium further comprises a solvent selected from the group consisting of toluene, ethylbenzene, tetrahydrofuran, hexane, and cyclohexane; and

a plurality of semiconductor nano-particles suspended in the medium.

2. The composition of claim 1, wherein the semiconductor nano-particles are quantum dots.

3. The composition of claim 2, wherein the quantum dots are hetero-structure quantum dots having an outer insulator coating.

4. The composition of claim 3, wherein the quantum dots each comprise an anisotropic nano-crystalline core comprising a first semiconductor material and having an aspect ratio between, but not including, 1.0 and 2.0, and a nano-crystalline shell comprising a second, different, semiconductor material at least partially surrounding the anisotropic nano-crystalline core.

5. The composition of claim 3, wherein the quantum dots each comprise a nano-crystalline core comprising a first semiconductor material, a nano-crystalline shell comprising a second, different, semiconductor material at least partially surrounding the nano-crystalline core, and a compositional transition layer disposed between, and in contact with, the nano-crystalline core and nano-crystalline shell, the compositional transition layer having a composition intermediate to the first and second semiconductor materials.

6. The composition of claim 3, wherein the quantum dots each comprise a nano-crystalline core comprising a first semiconductor material, a nano-crystalline shell comprising a second, different, semiconductor material at least partially surrounding the nano-crystalline core, a nano-crystalline outer shell at least partially surrounding the nano-crystalline shell, the nano-crystalline outer shell comprising a third semiconductor material different from the first and second semiconductor materials, and a compositional transition layer disposed between, and in contact with, the nano-crystalline shell and the nano-crystalline outer shell, the compositional transition layer having a composition intermediate to the second and third semiconductor materials.

7. The composition of claim 3, wherein the outer insulator coating comprises a layer of material selected from the group consisting of silica (SiO_x), titanium oxide (TiO_x), zirconium oxide (ZrO_x), alumina (AlO_x), and hafnia (HfO_x).

8. A composition, comprising:

a medium comprising ceramic precursor molecules, the medium a liquid or gel at 25 degrees Celsius, wherein the ceramic precursor molecules are thermal or ultra-violet (UV) labile β

-chloropolysilsequioxane molecules; and

a plurality of semiconductor nano-particles suspended in the medium, wherein the semiconductor nano-particles are hetero-structure quantum dots having an outer insulator coating, wherein the hetero-structure quantum dots each comprise;

a nano-crystalline core comprising a first semiconductor material;

a nano-crystalline shell comprising a second, different, semiconductor material at least partially surrounding the nano-crystalline core; and

a compositional transition layer disposed between, and in contact with, the nano-crystalline core and nano-crystalline shell, the compositional transition layer having a composition intermediate to the first and second semiconductor materials.

9. The composition of claim 8, wherein the medium is solvent-free.

10. The composition of claim 8, wherein the hetero-structure quantum dots each further comprise a nano-crystalline outer shell at least partially surrounding the nano-crystalline shell, the nano-crystalline outer shell comprising a third semiconductor material different from the first and second semiconductor materials, and a compositional transition layer disposed between, and in contact with, the nano-crystalline shell and the nano-crystalline outer shell, the compositional transition layer having a composition intermediate to the second and third semiconductor materials.

11. The composition of claim 8, wherein the outer insulator coating comprises a layer of material selected from the group consisting of silica (SiO_x), titanium oxide (TiO_x), zirconium oxide (ZrO_x), alumina (AlO_x), and hafnia (HfO_x).

12. The composition of claim 8, wherein the nano-crystalline core of each of the hetero-structure quantum dots has an aspect ratio between, but not including, 1.0 and 2.0.

13. A composition, comprising:

a medium comprising ceramic precursor molecules, the medium a liquid or gel at 25 degrees Celsius, wherein the ceramic precursor molecules are thermal or ultra-violet (UV) labile β

-chloropolysilsequioxane molecules; and

a plurality of semiconductor nano-particles suspended in the medium, wherein the semiconductor nano-particles are hetero-structure quantum dots having an outer insulator coating, wherein the hetero-structure quantum dots each comprise;

a nano-crystalline core comprising a first semiconductor material;

a nano-crystalline shell comprising a second, different, semiconductor material at least partially surrounding the nano-crystalline core; and

a nano-crystalline outer shell at least partially surrounding the nano-crystalline shell, the nano-crystalline outer shell comprising a third semiconductor material different from the first and second semiconductor materials, and a compositional transition layer disposed between, and in contact with, the nano-crystalline shell and the nano-crystalline outer shell, the compositional transition layer having a composition intermediate to the second and third semiconductor materials.

14. The composition of claim 13, wherein the medium is solvent-free.

15. The composition of claim 13, wherein the outer insulator coating comprises a layer of material selected from the group consisting of silica (SiO_x), titanium oxide (TiO_x), zirconium oxide (ZrO_x), alumina (AlO_x), and hafnia (HfO_x).

16. The composition of claim 13, wherein the nano-crystalline core of each of the hetero-structure quantum dots has an aspect ratio between, but not including, 1.0 and 2.0.

17. A composition, comprising:

a medium comprising ceramic precursor molecules, the medium a liquid or gel at 25 degrees Celsius, wherein the ceramic precursor molecules are thermal or ultra-violet (UV) labile β

-chloropolysilsequioxane molecules; and

a plurality of semiconductor nano-particles suspended in the medium, wherein the semiconductor nano-particles are hetero-structure quantum dots having an outer insulator coating a layer of material selected from the group consisting of silica (SiO_x), titanium oxide (TiO_x), zirconium oxide (ZrO_x), alumina (AlO_x), and hafnia (HfO_x).

18. The composition of claim 17, wherein the hetero-structure quantum dots each comprise a nano-crystalline core having an aspect ratio between, but not including, 1.0 and 2.0.

19. The composition of claim 17, wherein the medium is solvent-free.