KR100837847B1 - Wavelength-converted Light Emitting Diode Using Phosphor And Manufacturing Method Of The Same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength conversion type light emitting diode using two or more phosphors, and a method of manufacturing the same, comprising: a light emitting diode chip attached to a package and emitting light; and a light absorbed and absorbed light emitted from the light emitting diode chip. Translucent film coated with two or more phosphors that emit excited light having a wavelength different from the wavelength so as not to overlap on the same surface and mounted at a predetermined distance on top of the chip so as to pass all the light emitted from the chip. It includes.

According to the present invention, a new color light can be obtained by efficiently converting the wavelength of light generated from the light emitting diode chip without losing the light generated by absorbing light between the coated phosphors, in particular red (R), green By combining the phosphors of (G) and blue (B), an effect of realizing white light can be obtained.

Wavelength conversion type, light emitting diode, phosphor

Description

Wavelength-Converted Light Emitting Diode Using Phosphor And Manufacturing Method Of The Same}

1 is a cross-sectional view schematically showing a wavelength conversion type light emitting diode using a phosphor according to an embodiment of the prior art.

Figure 2 is a schematic diagram showing a stencil method that can be used in the process of forming the phosphor layer according to an embodiment of the prior art.

Figure 3 is a schematic cross-sectional view showing a wavelength conversion type light emitting diode using a phosphor according to an embodiment of the present invention and an enlarged view of the coated film.

4 is a schematic view showing a state in which white light is implemented through a wavelength conversion type light emitting diode using a phosphor according to an embodiment of the present invention.

           ｝ Explanation of symbols for main part of drawing

100, 200: light emitting diode package

104, 204: encapsulant

105, 115, 205: light emitting diode chip

106,206: metal (Au) wire

110: wafer

120: substrate opened in chip size

101: red phosphor particles

102: green phosphor particles

103: blue phosphor particles

201: Translucent film coated with red phosphor 201a: Red light

202: Translucent film coated with green phosphor 202a: Green light

203: Translucent film coated with blue phosphor 203a: Blue light

The present invention relates to a wavelength conversion type light emitting diode using two or more phosphors, and more particularly, by coating two or more different phosphors on the same side of the light-transmitting film without mixing them, the generated light is not absorbed by the red phosphor. The present invention relates to a wavelength conversion type light emitting diode that generates light of high color by modifying the wavelength of light emitted from a light emitting diode chip.

The light emission of the white light emitting diode is basically due to the inherent properties of the semiconductor and the phosphor, and is not heat or discharge light. Therefore, unlike ordinary incandescent light bulbs, LED lighting fixtures are not hot to touch and are safe and have a long lifespan. In addition, since it does not contain harmful substances such as glass, mercury, and organic substances that cause environmental pollution, it is an illumination light source that is friendly to the global environment. Therefore, it can be applied not only to general lighting but also in various fields, and a huge market is expected to be formed in the next 10 years.

Semiconductor light emitting diodes have a monochromatic property, mainly emitting light of a predetermined wavelength. Therefore, in order to obtain white light, white light is realized by combining chips emitting red, green, blue (Red, Green, Blue, RGB) light. However, this method has a problem in obtaining desired white light due to irregular hue or luminance of the light emitting diode.

As another method, a method of converting a portion of light of a blue or ultraviolet light emitting device using a phosphor and mixing and combining the light into white light or red, green and blue (hereinafter referred to as 'RGB') in an ultraviolet light emitting diode A method of combining white phosphors to produce white light is also used. However, these methods are difficult to use practically because the efficiency of the red phosphor decreases and the red phosphor absorbs light of different wavelengths, thereby lowering the overall luminous efficiency.

1 is a cross-sectional view showing the structure of a white light emitting device for emitting white light using an RGB phosphor according to an embodiment of the prior art, the contents of Korean Patent Publication No. 2004-0029684. In the above embodiment, in order to manufacture a white light emitting device, first, an ultraviolet light emitting diode is bonded to a package, the ultraviolet light emitting diode is wire-bonded with a lead frame, and then mixed with RGB phosphors and applied to various polymer resins, followed by thermal crosslinking. The light emitting diode is manufactured.

However, the above embodiments have disadvantages in that different phosphor materials are not uniformly mixed with the polymer resin, so that the brightness and efficiency of the white light are deteriorated, and the problem that the red phosphor absorbs light of different wavelengths is not improved.

Figure 2 is a schematic view showing a light emitting device using a phosphor according to another embodiment of the prior art, the content of the invention of US Patent No. 6664265. In the above embodiment, a stenciling method is used as a method of forming the formed body on the light emitting diode.

Referring to FIG. 2, the white light emitting diode according to the exemplary embodiment of the prior art has a substrate 120 that is slightly larger than the size of the light emitting diode on the top surface of the wafer 110 on which the plurality of light emitting diodes 115 are formed. After forming and forming the phosphor layer is prepared by cutting into individual chip sizes. Thus, the phosphor layer is evenly coated on the top and side surfaces of the light emitting diode. However, this process is difficult to realize in general SMEs because it can be manufactured only if there is a semiconductor fab manufacturing line, and it can be applied to all types of light emitting diodes. have.

In addition, Korean Patent Application No. 10-2004-0000094 filed for a white light emitting diode composed of a double mold, and Korean Patent Application No. 10-2001-7006555 is for a patent coated with a thin fluorescent film, Republic of Korea Patent Application No. 10-2003-0070500 discloses a method of coating phosphors by spin coating.

In addition, a technology for realizing white by applying a phosphor to a reflector has been announced (STANLEY).

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting device in which various lights are uniformly mixed through phosphors by preventing light from being absorbed with each other between phosphors for converting wavelengths in order to solve the problems of the prior art.

It is still another object of the present invention to convert a primary light emitted from a chip mounted on a light emitting diode package into one or more frequencies of different light without light loss, thereby emitting white light having high luminance and clear color tones; It is to provide a manufacturing method.

In order to achieve the above object, a wavelength conversion type light emitting diode using the phosphor of the present invention is different from a light emitting diode chip attached to a package and emitting light, and a wavelength of light absorbing and absorbing light emitted from the light emitting diode chip. A phosphor for emitting light having a wavelength is coated on one surface, and includes a transmissive film mounted at a predetermined distance on top of the chip so as to pass all the light emitted from the chip.

In the present invention, the light-transmitting film is characterized in that the different phosphors are coated so as not to overlap each other on the same side of the two or more films.

In the present invention, preferably, the light-transmitting film includes one or more transparent materials selected from the group consisting of polycarbonate, polymethylmethacrylate, polypropylene, quartz, and glass.

In the present invention, the phosphor is preferably any one phosphor selected from the group consisting of a sulfide-based, silicate-based, yttrium-aluminum-garnet (YAG) -based red phosphor, a green phosphor, a blue phosphor, and a yellow phosphor. It includes.

In the present invention, the light transmissive film is coated by any one method selected from the group consisting of phosphor jet ink printing, screen printing, silk printing, physical vapor deposition.

In the present invention, preferably, the light emitting diode chip includes emitting ultraviolet light or blue light.

In the present invention, the light emitting diode chip is preferably selected from the group consisting of a flip chip, a vertical chip or a general chip capable of at least two wire bonding on the upper surface.

In the present invention, an encapsulant is filled or not filled between the light emitting diode chip and the light-transmitting film coated with the phosphor.

In order to achieve the above object, a method of manufacturing a wavelength converting light emitting diode using the phosphor of the present invention comprises the steps of coating two or more different phosphors so as not to overlap each other on the same surface of the transparent transparent film made of inorganic or organic, and Cutting the coated light-transmitting film into a light emitting diode package, and mounting the cut film to pass all of the emitted light at a predetermined distance on top of the light emitting diode chip.

In the present invention, the phosphor includes one phosphor selected from the group consisting of a sulfide-based, silicate-based, yttrium-aluminum-garnet (YAG) -based phosphor, a green phosphor, a blue phosphor, and a yellow phosphor. .

In the present invention, the light-transmitting film includes a phosphor coated by any one method selected from the group consisting of inkjet printing, screen printing, silk printing, physical vapor deposition.

In the present invention, before mounting the coated light-transmitting film on top of the light emitting diode chip, the method further comprises the step of filling an encapsulant between the light emitting diode chip and the film to be mounted.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In adding reference numerals to the components of the following drawings, the same components, even if displayed on the other drawings to have the same reference numerals as possible, it is determined that the gist of the present invention may unnecessarily obscure Detailed descriptions of well-known functions and configurations will be omitted.

3 is a side cross-sectional view schematically showing a wavelength conversion type light emitting diode using a phosphor according to an embodiment of the present invention and an enlarged top view of a coated surface of a light-transmitting film mounted on an LED chip.

By mixing the light of the wavelength converted from the light emitting diode chip through the embodiment according to Figure 3 can mainly obtain white light.

In the above embodiment, the light emitting diode chip attached to the bottom surface of the light emitting diode package is a general type chip capable of bonding two or more wires to the metal electrode layer deposited on the top, or a flip chip, a vertical chip, and other technical fields of the present invention. Anyone skilled in the art will select from among various types of chips known from known techniques.

In the above embodiment, the light emitting diode chip may be a known light emitting diode capable of emitting light of various colors, and more preferably, a light emitting diode emitting light of a wavelength in a blue or ultraviolet region.

In the above embodiment, the encapsulant may or may not be filled in the space made by the light emitting diode and the light-transmitting film mounted thereon. As a material of a general encapsulation material, an epoxy or silicone material is used, but is not necessarily limited thereto, and those skilled in the art may use a known encapsulation material.

In one embodiment of the prior art, the phosphor is mixed with the material of the encapsulation material surrounding the light emitting diode, but the embodiment does not include the phosphor in the encapsulant.

Referring to FIG. 3, a light-transmitting film coated with a phosphor on the upper part separated by a predetermined distance from the light emitting diode is cut and mounted to fit the light emitting diode package.

In the above embodiment, the light-transmitting film is coated with two or more phosphors, which is coated by any one of inkjet printing, screen printing, silk printing, physical vapor deposition, and the like, and preferably coated by silk printing. However, the present invention is not necessarily limited thereto, and any method can be used as long as a person skilled in the art can know a known thin film coating method on a substrate.

In the case where two or more kinds of phosphors are coated in various ways, each of the phosphors may be coated separately on the light-transmissive film so that there is no overlap between the phosphors, but on the same side of the inside or the outside of the light-transmissive film. In particular, the form of the coating may be coated in the form of a checkerboard as shown in the enlarged view of FIG. In the case of coating in the form of a checkerboard it can give a variety of wavelength conversion method by coating the phosphor by changing the size and shape of the square of the basic unit. In other words, if the area where the red phosphor is coated is increased and the area where the green and blue phosphors are coated is reduced, the light emitted from the light emitting diode is more likely to be converted into red light. Will be.

However, if the phosphor is not necessarily coated in the form of a checkerboard pattern, and the phosphors do not overlap each other, they may be coated in various patterns and forms such as stripes.

The light-transmitting film coated with the phosphor is preferably a transparent substrate, and particularly preferably a polymer material having properties of light resistance and heat resistance, and may be either an organic substrate or an inorganic substrate. Particularly, in one embodiment of the present invention, at least one of polycarbonate, polymethyl methacrylate, polypropylene, glass, and quartz is used.

The phosphor may be any one phosphor selected from the group consisting of a sulfide-based, silicate-based, yttrium-aluminum-garnet (YAG) -based phosphor, a green phosphor, a blue phosphor, and a yellow phosphor, but is not limited thereto. May be any known wavelength conversion phosphor.

Translucent films coated with two or more kinds of phosphors in various forms are usually made in large areas and can be cut and used to match the size of light emitting diodes attached to different light emitting devices.

It is preferable to mount the cut phosphor film so as to fit snugly on top of the light emitting diode so that all light generated from the chip of the light emitting diode is emitted to the outside through the light transmitting film.

Referring to FIG. 3, FIG. 4 is a schematic view showing that white light is implemented through a wavelength converting light emitting diode using a phosphor according to an embodiment of the present invention.

Referring to FIG. 4, blue or ultraviolet light is emitted from the chip of the light emitting diode, but all emitted light is emitted to the outside through the light-transmitting film coated with the phosphor. In the embodiment, when the red phosphor coating portion 201, the green phosphor coating portion 202, the blue phosphor coating portion 203 is coated on the transparent film like a checkerboard, the wavelength of the light generated according to the type and the coating area of the phosphor The red light 201a, green light 202a, and blue light 203a are respectively changed. Finally, these converted lights are mixed to indicate that light or white light of a desired color can be expressed.

Light emitting diodes equipped with a light-transmitting film coated on top of two or more different kinds of phosphors that emit excited light having a wavelength different from the wavelength of light absorbed by the light emitted from the light emitting diode chip are various in the prior art. It is possible to solve the problem of light absorption between the phosphors generated when the phosphors are mixed together. The red phosphor material mainly absorbs light of wavelengths converted from other phosphors, thereby reducing the overall brightness and efficiency of the light. One embodiment of the present invention solves this problem by preventing these heterogeneous phosphors from mixing with each other. Can be.

In addition, in the conventional method of manufacturing a wavelength conversion light emitting diode by mixing a phosphor material with an encapsulant, there is a problem that the phosphor is difficult to uniformly apply due to the difference in precipitation rate in the liquid encapsulant due to the difference in specific gravity between the phosphors. there was. In an embodiment of the present invention, since the encapsulant is not mixed with the phosphor material in any case where the encapsulant is filled or not filled in the gap between the light emitting diode chip and the upper light-transmitting film, there is no fear of the above-mentioned problem and the light having a desired wavelength or Adjustment to express white light is possible.

In addition, by adjusting the area to be coated according to the efficiency of the phosphor, it is possible to adjust the color tone and luminance of the light emitted as a result. That is, it is possible to effectively control the color of the overall light by coating a phosphor having a low efficiency such as a red phosphor to occupy a large area, and coating a phosphor having a high efficiency such as a blue phosphor to occupy a small area.

The wavelength conversion light emitting diode according to an embodiment of the present invention can be used as a light emitting device for white light emission. In the above embodiment, the light emitting diode is preferably a light emitting diode that generates ultraviolet light or blue light having a short wavelength series, and the phosphor may select and use two or more suitable fluorescent materials capable of obtaining white light by converting the short wavelength light.

In the method of manufacturing a wavelength conversion type light emitting diode using the phosphor of the present invention, in the general method of manufacturing a light emitting diode, coating two or more different kinds of phosphors so as not to overlap each other on the same surface of the transparent transparent film made of inorganic or organic And cutting it to the light emitting diode package and mounting the film to pass all the light emitted at a certain distance on top of the light emitting diode chip. In some cases, before mounting the coated light-transmitting film on top of the light emitting diode chip, a step of filling an encapsulant between the light emitting diode chip and the film to be mounted may be further added.

As described above, the present invention has been described with reference to a preferred embodiment of the present invention, but those skilled in the art can vary the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that modifications and variations can be made.

As described above, according to the present invention, since the wavelengths of light emitted from the chip are modified through the transmissive film coated on the same surface so that two or more phosphors do not overlap, the loss of light generated by absorbing each other between the phosphors is prevented. It works.

In addition, since there is no loss due to absorption between the phosphors, the hue and luminance of the light having different wavelengths are high, and the efficiency of the white light in which light of various wavelengths is combined is high.

In addition, the light emitted from the light emitting diode chip is configured to pass through the film coated with the upper phosphor, thereby resulting in a high conversion efficiency of the white light finally converted.

As a result, it is possible to improve the luminous efficiency and reliability by improving the problem of coating and low dispersion of the non-uniform phosphor in the wavelength conversion light emitting diode device using the conventional phosphor and the photoreaction in the short wavelength region due to the phosphor mixed with the encapsulant. Have.

Claims (12)

A light emitting diode chip attached to the package and emitting light; And Different phosphors emitting light having a wavelength different from the wavelength of light absorbed by the light emitted from the light emitting diode chip are coated so as not to overlap each other on the same surface of the two or more films, and the light emitted from the chip A wavelength conversion type light emitting diode using a phosphor, characterized in that it comprises a light-transmitting film mounted at a predetermined distance on the top of the chip to pass all. delete The method of claim 1, wherein the light-transmitting film is a wavelength conversion type light emitting diode using a phosphor, characterized in that at least one transparent material selected from the group consisting of polycarbonate, polymethyl methacrylate, polypropylene, quartz, glass. The phosphor of claim 1, wherein the phosphor is any one phosphor selected from the group consisting of a sulfide-based, silicate-based, yttrium-aluminum-garnet (YAG) -based red phosphor, a green phosphor, a blue phosphor, and a yellow phosphor. A wavelength conversion type light emitting diode using a phosphor, characterized in that. The method of claim 1, wherein the light-transmitting film is a wavelength conversion type light emitting diode using a phosphor, characterized in that the coating by any one method selected from the group consisting of inkjet printing, screen printing, silk printing, physical vapor deposition. The wavelength conversion type light emitting diode using a phosphor according to claim 1, wherein the light emitting diode chip emits ultraviolet light or blue light. The wavelength conversion type light emitting diode of claim 1, wherein the light emitting diode chip is selected from a group consisting of a flip chip, a vertical chip, or a general chip capable of bonding two or more wires on an upper surface thereof. The wavelength conversion type light emitting diode of claim 1, wherein an encapsulant is filled or not filled between the light emitting diode chip and the light-transmitting film coated with the phosphor. Coating two or more different phosphors so as not to overlap each other on the same side of an inorganic or organic transparent light-transmitting film; Cutting the coated light-transmitting film into a light emitting diode package; And And mounting the cut film to pass all of the emitted light at a predetermined distance on top of the LED chip. The phosphor of claim 9, wherein the phosphor is any one phosphor selected from the group consisting of a sulfide-based, silicate-based, yttrium-aluminum-garnet (YAG) -based red phosphor, a green phosphor, a blue phosphor, and a yellow phosphor. A method of manufacturing a wavelength conversion light emitting diode using a phosphor, characterized in that. 10. The method of claim 9, wherein the light-transmitting film is a fluorescent material of the wavelength conversion type light emitting diode using a phosphor, characterized in that the coating by any one method selected from the group consisting of inkjet printing, screen printing, silk printing, physical vapor deposition method Way. The wavelength converting type using the phosphor according to claim 9, further comprising filling an encapsulant between the LED chip and the film to be mounted before mounting the coated light-transmitting film on top of the LED chip. Method of manufacturing a light emitting diode.

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