Nanocrystal doped matrixes

• US 20060068154A1
• Filed: 01/13/2005
• Published: 03/30/2006
• Est. Priority Date: 01/15/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Nanosys Incorporated (Shoei Electronic Materials, Inc.)
• Inventors: Chen, Jian, Freeman, William P., Parce, J. Wallace, Scher, Erik C., Whiteford, Jeffery A., Dubrow, Robert S.
• Granted Patent: US 7,374,807 B2
• Time in Patent Office: Days
• US Class Current: 428/76
• 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: C08K 3/30 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C09D 11/037 characterised by the pigment
• CPC Class Codes: C09D 5/00 Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced electrically insulating plastics, resins or waxes H01B3/30; Filling pastes
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/67 Particle size smaller than 100 nm
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/565 with zinc cadmium
• CPC Class Codes: C09K 11/883 with zinc or cadmium
• CPC Class Codes: G02B 1/11 Anti-reflection coatings
• CPC Class Codes: G02B 3/00 Simple or compound lenses
• CPC Class Codes: G02B 3/0006 Arrays G02B3/02, G02B5/188 take precedence
• CPC Class Codes: G02B 5/08 Mirrors vehicle mirrors involving special optical features B60R1/08
• 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 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H05B 33/145 Arrangements of the electroluminescent material
• CPC Class Codes: Y10S 977/715 On an organic substrate
• CPC Class Codes: Y10S 977/753 with polymeric or organic binder
• CPC Class Codes: Y10S 977/834 : Optical properties of nanomaterial, e.g. specified transparency, opacity, or index of refraction
• CPC Class Codes: Y10T 428/23 : Sheet including cover or casing
• CPC Class Codes: Y10T 428/239 : Complete cover or casing

Abstract

The present invention provides matrixes doped with semiconductor nanocrystals. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes of the present invention can also be utilized in refractive index matching applications. In other embodiments, semiconductor nanocrystals are embedded within matrixes to form a nanocrystal density gradient, thereby creating an effective refractive index gradient. The matrixes of the present invention can also be used as filters and antireflective coatings on optical devices and as down-converting layers. The present invention also provides processes for producing matrixes comprising semiconductor nanocrystals.

Claims

1. A polymeric layer, comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, wherein said nanocrystals have a size and a composition such that said nanocrystals absorb visible light,

wherein said polymeric layer scatters a minimal portion of light that enters said layer.

5. The polymeric layer as in any one of claims 1-4, wherein said polymeric layer coats an optical device.

6. The polymeric layer of claim 5, wherein said optical device is a refractive lens or a reflective element.

7. The polymeric layer as in any one of claims 1-4, wherein said polymeric layer encapsulates an active device.

8. The polymeric layer of claim 7, wherein said active device is a light emitting diode.

9. The polymeric layer as in any one of claims 1-4, wherein said polymer is silicone.

10. The polymeric layer as in any one of claims 1-4, wherein said size of said nanocrystals is between about 1-10 nm.

11. The polymeric layer of claim 10, wherein said size of said nanocrystals is between about 1-4 nm.

12. The polymeric layer of claim 10, wherein said size of said nanocrystals is between about 1-3 nm.

13. The polymeric layer as in any one of claims 1-4, wherein said nanocrystals further comprise miscibility-enhancing ligands attached to a surface of said nanocrystals.

14. The polymeric layer as in any one of claims 1-4, wherein said polymeric layer has an effective refractive index of greater than about 1.5.

15. The polymeric layer of claim 14, wherein said polymeric layer has an effective refractive index of about 1.8.

16. The polymeric layer as in any one of claims 1-4, wherein said layer is greater than about 0.5 mm in thickness.

17. The polymeric layer of claim 1, wherein said nanocrystals absorb blue light.

18. The polymeric layer of claim 1, wherein said nanocrystals absorb green light.

19. The polymeric layer of claim 1, wherein said nanocrystals absorb red light.

2. A polymeric layer, comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, wherein said nanocrystals have a size and a composition such that said nanocrystals absorb ultraviolet light,

wherein said polymeric layer scatters a minimal portion of light that enters said layer.

3. A polymeric layer, comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, wherein said nanocrystals have a size and a composition such that said nanocrystals absorb near-infrared light,

wherein said polymeric layer scatters a minimal portion of light that enters said layer.

4. A polymeric layer, comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, wherein said nanocrystals have a size and a composition such that said nanocrystals absorb infrared light,

wherein said polymeric layer scatters a minimal portion of light that enters said layer.

20-32. -32. (canceled)

33. A polymeric layer that encapsulates an active device, said active device having an effective refractive index, n1, said layer comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, said polymeric layer having an inner boundary in contact with said active device and an outer boundary in contact with a medium having an effective refractive index, n2, wherein said polymeric layer has an effective refractive index less than or equal to n1 at said inner boundary and an effective refractive index greater than or equal to n2 at said outer boundary.

34. The polymeric layer of claim 33, wherein n1 is greater than n2.

35. The polymeric layer of claim 33, wherein said layer has a nanocrystal density gradient, said gradient being highest at said inner boundary and lowest at said outer boundary.

36. The polymeric layer of claim 35, wherein said nanocrystal density gradient is substantially linear throughout said layer.

37. The polymeric layer of claim 33, wherein said active device is a light emitting diode.

41. The polymeric layer of claim 33, wherein said nanocrystals have a size between about 1-3 nm.

38-40. -40. (canceled)

42-51. -51. (canceled)

52. A process for preparing a polymeric layer, comprising:

(a) mixing semiconductor nanocrystals at a first density with a solvent and a polymer to form a first mixture;

(b) coating a substrate material with the first mixture; and

(c) evaporating the solvent to form the polymeric layer, wherein the polymeric layer has an effective refractive index of n1.

53-85. -85. (canceled)

86. A down converting nanocomposite device, comprising:

(a) two or more semiconductor nanocrystal phosphors of two or more sizes, said nanocrystal phosphors emit light at one or more selected wavelengths, and providing a CRI of greater than about 80;

(b) a matrix with a high index of refraction, low UV degradation and/or matched thermal expansion; and

(c) a chemical structure coupling the matrix to said nanocrystal phosphors.

87-94. -94. (canceled)

95. A polymeric layer, comprising:

(a) a polymer; and

(b) semiconductor nanocrystals embedded within said polymer, wherein said nanocrystals have miscibility-enhancing ligands conjugated to their surface, and wherein said ligands comprise an alkane chain of between 6 and 18 carbons in length.

96. The polymeric layer of claim 95, wherein said ligands comprise an alkane chain of between 12 and 18 carbons in length.

100. The polymeric layer of claim 95, wherein said semiconductor nanocrystals have a size between about 1-3 nm.

102. The polymeric layer of claim 95, wherein said layer scatters less than about 50% of light that enters said polymeric layer.

103. The polymeric layer of claim 95, wherein said layer scatters less than about 20% of light that enters said polymeric layer.

104. The polymeric layer of claim 95, wherein said layer scatters less than about 15% of light that enters said polymeric layer.

97-99. -99. (canceled)

101. (canceled)

105-106. -106. (canceled)