Light emitting diode

Abstract

Provided are a light emitting diode, a method of manufacturing the same, and a use thereof. The light emitting diode having excellent initial light flux and excellent color uniformity and dispersion, the method of manufacturing the same, and the use thereof may be provided.

Claims

1. A light emitting diode, comprising: an light emitting diode chip; a first silicone film layer formed on the light emitting diode chip; and a second silicone film layer formed on the first silicone film layer, comprising a phosphor, and having a refractive index lower than that of the first silicone film layer while excluding the phosphor, wherein the first silicone film layer comprises an aryl group binding to a silicon atom, and wherein the first or second silicone film layer is a cured film layer of a composition including an organopolysiloxane having an average unit of Formula 1 and an organopolysiloxane having an average unit of Formula 11:
P.sub.aQ.sub.bSiO.sub.(4-a-b)/2[Formula 1]
H.sub.cQ.sub.dSiO.sub.(4-c-d)/2[Formula 11] where P is an alkenyl group, Q is an epoxy group or a monovalent hydrocarbon group, a+b is in a range of 0.8 to 2.2, and a/(a+b) is a number within a range of 0.001 to 0.15, and c and d are numbers such that c+d is 1 to 2.8 and c/(c+d) is 0.001 to 0.34.

2. The light emitting diode according to claim 1, wherein the first silicone film layer has a refractive index with respect to light with a wavelength of 400 nm of 1.5 or more.

3. The light emitting diode according to claim 1, wherein the second silicone film layer has a refractive index with respect to light with a wavelength of 400 nm of 1.6 or less while excluding a phosphor.

4. The light emitting diode according to claim 1, wherein the first silicone film layer comprises an epoxy group binding to a silicon atom.

5. The light emitting diode according to claim 4, wherein a ratio (E/Si) of a mole of an epoxy group (E) with respect to a mole of total silicon atoms (Si) included in the first silicone film is 0.001 to 0.15.

6. The light emitting diode according to claim 1, wherein the first silicone film layer comprises a filler having a refractive index with respect to light with a wavelength of 400 nm of 1.55 or more.

7. The light emitting diode according to claim 1, wherein the first silicone film layer comprises scattering particles.

8. The light emitting diode according to claim 7, wherein the scattering particles have an average particle diameter of 100 nm or more, and an absolute value of a difference in refractive index from that of the first silicone film layer excluding the scattering particles of 0.15 to 1.0.

9. The light emitting diode according to claim 7, wherein a weight ratio of the scattering particles in the first silicone film layer is 0.1 wt % to 30 wt %.

10. A liquid crystal display, comprising the light emitting diode of claim 1.

11. A light apparatus, comprising the light emitting diode of claim 1.

12. A method of manufacturing a light emitting diode, comprising: transferring a first silicone film onto an light emitting diode chip; and transferring a second silicone film comprising a phosphor and having a refractive index lower than that of the first silicone film while excluding the phosphor, onto the first silicone film, wherein the first silicone film layer comprises an aryl group binding to a silicon atom, and wherein the first or second silicone film layer is a cured film layer of a composition including an organopolysiloxane having an average unit of Formula 1 and an organopolysiloxane having an average unit of Formula 11:
P.sub.aQ.sub.bSiO.sub.(4-a-b)/2[Formula 1]
H.sub.cQ.sub.dSiO.sub.(4-c-d)/2[Formula 11] where P is an alkenyl group, Q is an epoxy group or a monovalent hydrocarbon group, a+b is in a range of 0.8 to 2.2, and a/(a+b) is a number within a range of 0.001 to 0.15, and c and d are numbers such that c+d is 1 to 2.8 and c/(c+d) is 0.001 to 0.34.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram of a structure of an exemplary LED.

DESCRIPTION OF REFERENCE NUMERALS

(2) 101: LED chip

(3) 102: first silicone film layer

(4) 103: second silicone film layer

Effects

(5) A light emitting diode having excellent initial light flux and excellent color uniformity and dispersion, a method of manufacturing the same, and a use thereof can be provided.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(6) Hereinafter, exemplary embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms. The following embodiments are described in order to enable those of ordinary skill in the related art to embody and practice the present invention.

(7) Hereinafter, the abbreviations Vi, Ph, Me, and Ep refer to a vinyl group, a phenyl group, a methyl group, and a 3-glycidoxypropyl group.

(8) 1. Measurement of Optical Characteristics

(9) Optical characteristics (color uniformity, color dispersion, and initial light flux) were measured using an integration sphere (Otsuka, LE-3400) by applying a current to an LED package manufactured in Example or Comparative Example.

EXAMPLE 1

(10) Formation of First Silicone Film

(11) A curable composition was prepared by mixing organopolysiloxanes represented by Formulas A to C (blending amount: 20 g of Formula A, 60 g of Formula B, and 18 g of Formula C), blending a catalyst (platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane) at a content of Pt(0) of 2 ppm, and curing the resulting mixture to have a refractive index with respect to a wavelength of 400 nm of approximately 1.56. A first silicone film was formed by preparing a coating composition by mixing approximately 10 g of alumina having an average particle diameter of approximately 10 nm with 98 g of the curable composition, and coating the coating composition on an ethylene tetrafluoroethylene (ETFE) film to have a final thickness of approximately 10 m, and maintaining the resulting film at 80 C. for 5 minutes.
(ViMe.sub.2SiO.sub.1/2).sub.2(Me.sub.2SiO.sub.2/2).sub.5(Ph.sub.2SiO.sub.2/2).sub.10[Formula A]
(ViMe.sub.2SiO.sub.1/2).sub.2(Ph.sub.2SiO.sub.2/2).sub.0.5(EpMeSiO.sub.2/2).sub.0.2(PhSiO.sub.3/2).sub.7[Formula B]
(HMe.sub.2SiO.sub.1/2).sub.2(Ph.sub.2SiO.sub.2/2)[Formula C]

(12) Formation of Second Silicone Film

(13) A curable composition was prepared by mixing organopolysiloxanes represented by Formulas C to E (blending amount: 20 g of Formula D, 60 g of Formula E, and 18 g of Formula C), blending a catalyst (platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane) at a content of Pt(0) of 2 ppm, and curing the resulting mixture to have a final refractive index of approximately 1.49. A second silicone film was formed by preparing a coating composition by mixing 200 g of a YAG as a phosphor and approximately 3 g of silica having an average particle diameter of approximately 10 nm with 98 g of the curable composition, and coating the coating composition on an ETFE (ethylene tetrafluoroethylene) film to have a final thickness of approximately 100 m as described in the formation of the first silicone film, and maintaining the resulting film at 80 C. for 5 minutes.
(ViMe.sub.2SiO.sub.1/2).sub.2(Me.sub.2SiO.sub.2/2).sub.20(Ph.sub.2SiO.sub.2/2).sub.10[Formula D]
(ViMe.sub.2SiO.sub.1/2).sub.2(Me.sub.2SiO.sub.2/2)1(EpMeSiO.sub.2/2).sub.0.2(PhSiO.sub.3/2).sub.4(SiO.sub.4/2).sub.0.5[Formula E]
(HMe.sub.2SiO.sub.1/2).sub.2(Ph.sub.2SiO.sub.2/2)[Formula C]

(14) Manufacture of LED Package

(15) Each manufactured film was cut into a suitable size, a first silicone film was transferred to an LED chip (an LED chip for a 3535 LED package manufactured of polyphthalamide (PPA)), a fluorine resin film was removed, and then the resulting product was maintained at 150 C. for 5 minutes. Subsequently, a second silicone film was transferred onto the first silicone film as described above, a fluorine resin film was removed, and the resulting product was maintained at 150 C. for 4 hours to cure. Here, during the transfer of the silicone film, a gold wire contacting the LED and an external contact terminal was coated. Subsequently, a transparent silicone resin generally applied as an encapsulant was injected into a reflector, and maintained at 150 C. for 4 hours, thereby manufacturing an LED package.

EXAMPLE 2

(16) An LED package was manufactured by the same method as described in Example 1, except that a coating solution prepared by blending 98 g of the curable composition, which was the same as being used to form the first silicone film of Example 1 10 g of alumina particles having an average particle diameter of approximately 10 nm, and 200 g of a phosphor (YAG), was used to form a first silicone film.

EXAMPLE 3

(17) An LED package was manufactured by the same method as described in Example 1, except that a coating solution prepared by blending 98 g of the curable composition, which was the same as being used to form the first silicone film of Example 1, and 200 g of a phosphor (YAG), was used to form a first silicone film, and a coating solution prepared by blending 98 g of the curable composition, which was the same as being used to form the second silicone film of Example 1, and 200 g of a phosphor (YAG), was used to form a second silicone film.

EXAMPLE 4

(18) An LED package was manufactured by the same method as described in Example 1, except that a coating solution prepared by blending 98 g of the curable composition, which was the same as being used to form the first silicone film of Example 1, 200 g of a phosphor (YAG), and approximately 3 g of titanium oxide particles as scattering particles having a refractive index of approximately 1.63 and an average particle diameter of approximately 100 nm, was used to form a first silicone film.

COMPARATIVE EXAMPLE 1

(19) An LED package was manufactured by the same method as described in Example 1, except that a coating solution prepared by blending 5 g of a phosphor (YAG) with 100 g of the curable composition which was the same as being used in formation of a second silicone film in Example 1 was dispensed on a reflector to cover an entire surface of a diode and maintained at 150 C. for 4 hours, which was equal to conventionally form an encapsulant of the LED package. The LED chip used in this process was the same as that used in Example 1.

COMPARATIVE EXAMPLE 2

(20) An LED package was manufactured as described in Example 1, except that a first silicone film was not formed and only a second silicone film was transferred to an LED chip.

COMPARATIVE EXAMPLE 3

(21) An LED package was manufactured as described in Example 1, except that a first silicone film layer was formed, a coating solution prepared by dispersing a phosphor (YAG) in a toluene was coated on the first silicone film layer and baked at 150 C. to form a phosphor layer, but a second silicone film layer was not formed.

(22) Results of measuring physical properties of the curable compositions in Examples and Comparative Examples were summarized and listed in Table 1.

(23) TABLE-US-00001 TABLE 1 Color Initial light flux Color uniformity (u) dispersion (Cx) (lm/W) Example 1 0.001 0.001 93 Example 2 0.001 0.001 92 Example 3 0.001 0.001 90 Example 4 0.001 0.001 94 Comparative 0.008 0.005 83 Example 1 Comparative 0.001 0.001 85 Example 2 Comparative 0.010 0.008 79 Example 3