KR100702297B1 - Manufacturing method of white LED - Google Patents

Abstract

The present invention relates to a method of manufacturing a white LED, and in particular, after applying a fluorescent material of a mixture of red, blue, and green to a purple light emitting LED chip using a packaging substrate, the purple light emitting LED chip emits purple light. The present invention relates to a method of manufacturing a white LED that transmits light to the surface of the fluorescent material to produce white light in which three wavelengths of red, blue, and green are mixed.

Description

Manufacturing method of white LED {METHOD FOR MANUFACTURING A WHITE LED}             

1 shows a packaging lead frame of a white LED manufactured according to a conventional method;

2 shows a lead frame of a white LED made according to the invention;

3 shows a lead frame of another type of white LED made in accordance with the present invention;

4 is a structural diagram of a molding of a white LED according to the present invention; And

5 is a view showing a spectrum of a white LED according to the present invention.

* Explanation of symbols for main parts of the drawings

1: violet light emitting chip 2: three primary fluorescent material

3, 9: packaging lead frame 4: wire lead

5: lead frame electrode 10: substrate electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a white light emitting diode (LED), and in particular, after applying a fluorescent material of a mixture of red, blue, and green colors to a violet light emitting LED chip using a packaging substrate, The present invention relates to a method of manufacturing a white LED that transmits light to a surface of the fluorescent material by using a purple light emitting LED chip to emit purple light, thereby producing white light in which three wavelengths of red, blue, and green are mixed.

There are two conventional examples of the white LED manufacturing method.

The first method is a method of applying a yellow fluorescent substance (YAG) to a blue light emitting chip as described in Nichia, Taiwan Patent No. 383508.

However, the white light produced by the above method is composed of blue and yellow two-wavelenghs, which is suitable for indication, but not for lighting use and LCD color background light source. In addition, due to the difficulty of controlling the amount of the yellow fluorescent substance has a problem that the color of the light is biased to blue or yellow.

As a second method, there is a method of applying red, blue, and green mixed fluorescent materials to an ultraviolet light emitting chip as described in Taiwan Patent Registration No. 385063 of the present inventors, and then transmitting light to make white light appear.

The method is the most ideal method for transmitting three wavelengths of white light by transmitting ultraviolet rays through the three primary fluorescent materials. However, there have been many problems in manufacturing until the ultraviolet LED light emitting chip with high luminous efficiency does not appear. Nichia in Japan, which currently uses ultraviolet LEDs, has a wavelength of 371nm and power of 2-3mW. Similarly, Toyota Gosei's products in Japan have a 380nm three-wavelength length and power of about 2-3mW. The reason why it is difficult to manufacture high-efficiency ultraviolet LED light emitting chips is due to the material properties and manufacturing process.

In addition, until now there is no transparent resin that can cover ultraviolet rays, and most organic resins are used. Such organic resins absorb and heat ultraviolet rays, thereby reducing the lifespan and quality of LEDs.

The present invention provides a better white LED manufacturing technology through the study of defects of the conventional white LED, and provides a manufacturing method for producing a three-wavelength white LED using a violet light (wavelength 390 ~ 410nm) and a fluorescent material will be.

The white LED manufacturing technology of the present invention is a technology for producing white light by transmitting a violet light having a wavelength of 390 ~ 410nm through a fluorescent material, a technique of adding a yellow fluorescent material (YAG) to the blue light emitting chip or tri-fluorescence ultraviolet light It is different from the technology of making white light of three wavelengths through the material.

The reason for using purple light in the present invention is because Cree Corporation of the United States has made a highly efficient LED chip that produces more than 20mW of power using a wavelength between 390 and 395nm, which is higher than the current blue or ultraviolet ray. Has efficiency. In addition, his experiments revealed that fluorescent light (red, blue, and green) can be emitted evenly by violet light in the range of 390-410 nm.

among them:

The red fluorescent substance is Y ₂ O ₂ S: Eu, Gd

Green fluorescent material is ZnS: Cu, Al or Ca ₂ MgSi ₂ O ₇ : Cl,

The blue fluorescent substance is BaMgAl ₁₀ O ₁₇ or (Sr, Ca, BaMg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu.

With the right mix of red, blue and green, you can produce white light, different color temperatures or different colors of light.

Referring to Fig. 2, first, the red, blue, and green trichromatic phosphors 2 blended in an appropriate ratio produce sufficient white light from purple light. In addition, this white light can be adjusted between 3000 and 8000K to meet the different demands of the customer, and the red, blue and green three primary colors of fluorescent material 2 can also be adjusted by adjusting the ratio.

The violet light emitting chip 1 is fixed to the packaging lead frame 3 or the packaging lead frame 9, and the wire lead 4 is fixed to the LED light emitting chip, the lead frame electrode 5 (or the substrate electrode 10). ) And the packaging lead frame (or packaging lead frame 9), respectively. Next, an appropriately mixed trichromatic fluorescent substance 2 is applied directly or indirectly (see FIGS. 3 and 4) to the surface of the ultraviolet light emitting LED chip 1, and when it is transmitted through light, three wavelengths of white light are produced ( See FIG. 5).

The configuration of the trichromatic fluorescent substance 2 of the present invention is as follows.

The red fluorescent substance is Y ₂ O ₂ S: Eu, Gd,

Green fluorescent material is ZnS: Cu, Al or Ca ₂ MgSi ₂ O ₇ : Cl,

The blue fluorescent substance is BaMgAl ₁₀ O ₁₇ or (Sr, Ca, BaMg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu.

In addition to the above-described fluorescent substance, other fluorescent substances may be used. Therefore, the present invention is not only limited to the above-described fluorescent material, but also includes other fluorescent materials that generate other violet light wavelengths (390 to 410 nm).

Existing fluorescent materials have been studied only in the wavelength range of 254nm or 365nm. On the other hand, research on white light emission using purple light as in the present invention has been very few, which is due to the development of high efficiency purple light emitting LED chips only in recent years. The present invention relates to a technique for producing a fluorescent material into white light by using a high-efficiency purple light LED light emitting chip, according to the present invention can generate white light well and can also be generated in three wavelengths.

As described above, the present invention is applied to a violet light emitting LED chip consisting of a packaging substrate or a lead frame by directly or indirectly coating a fluorescent material mixed with three primary colors of red, blue and green by a known method. The method provides a method of manufacturing a white LED, the method comprising fixing the violet light emitting LED chip on a packaging substrate or a lead frame and connecting the electrode to an electrode, and the wavelength range of the violet light generated by the violet light emitting LED chip is from 390 nm to A method of manufacturing a white LED, characterized in that between 410nm, the packaging substrate can be a printed circuit board (PCB), a ceramic substrate, a silicon substrate, or a metal substrate manufacturing method of a white LED, characterized in that And the red fluorescent material is Y ₂ O ₂ S: Eu, Gd, and the green fluorescent material is ZnS: Cu, Al or Ca ₂ MgSi ₂ O ₇ : Cl, blue The fluorescent material provides BaMgAl ₁₀ O ₁₇ or (Sr, Ca, BaMg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu.

As described above, the present invention generates the white light having the highest luminous efficiency among the white LED manufacturing technology using a single chip, by producing a fluorescent material as white light using a high efficiency purple light LED light emitting chip. Have

Claims (4)

Coating a fluorescent material containing a mixture of three primary colors of red, blue, and green on a purple light emitting LED chip consisting of a packaging substrate or a lead frame, and then fixing the purple light emitting LED chip to the packaging substrate or lead frame, and then connecting the electrode to the electrode. The manufacturing method of the white LED characterized by the above-mentioned. The method of claim 1, The wavelength range of the ultraviolet light generated by the violet light emitting LED chip is 390nm ~ 410nm manufacturing method of the white LED. The method of claim 1, The packaging substrate is a printed circuit board (PCB), a ceramic substrate, a silicon substrate, or a metal substrate manufacturing method of a white LED, characterized in that. The method of claim 1, The red phosphor is Y ₂ O ₂ S: Eu, Gd, the green phosphor is ZnS: Cu, Al or Ca ₂ MgSi ₂ O ₇ : Cl, and the blue phosphor is BaMgAl ₁₀ O ₁₇ or (Sr, Ca, BaMg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu manufacturing method of a white LED.

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