KR100781924B1 - High power light emitting diode device comprising two kinds of phosphors - Google Patents

Abstract

A high output white LED device having high luminance and improved color characteristics and a method of manufacturing the same are disclosed. The high power white LED device according to an embodiment of the present invention includes a high power blue LED chip, an LED chip mounting member, a mold resin, and a yellow green phosphor and a green phosphor. The LED chip mounting member has an external connection terminal, and a predetermined wiring pattern electrically connected to the external connection terminal is formed on the surface and / or inside of the member. The LED chip is mounted on the LED chip mounting member. The LED chip is a high output LED chip electrically connected to an external connection terminal through a wiring pattern and having a rated current of about 500 to 720 mA. And the resin for mold seals an LED chip. The yellow green and green phosphors are evenly dispersed in the mold resin, and the light emitted from the LED chip, the yellow green phosphor, and the green phosphor combine with each other to form white light.

Description

High power light emitting diode device comprising two kinds of phosphors}

1A is a schematic cross-sectional view of a lamp type high power white LED device according to an embodiment of the present invention.

1B is a schematic cross-sectional view of a chip type high power white LED device according to another embodiment of the present invention.

1C is a schematic cross-sectional view of a top type high power white LED device composed of a double mold according to another embodiment of the present invention.

Figure 2a is a graph showing the excitation wavelength of the YAG phosphor used in the embodiment of the present invention and the emission wavelength by the YAG phosphor.

Figure 2b is a Sr _1-x S _x used in the embodiment of the present invention: a graph showing the emission wavelength by the phosphor Eu: Eu and the excitation wavelength of the phosphor Sr _1-x S _x.

3 is an emission spectrum of white light emitted from an LED chip having a wavelength of 440 nm, a YAG phosphor, and a tower LED device including an Sr _1-x S _x : Eu phosphor.

Figure 4 is a high power white LED device comprising only the YAG phosphor prepared according to the prior art and a high power white LED device comprising a YAG phosphor and Sr _1-x S _x : Eu phosphor prepared according to an embodiment of the present invention It is a figure which shows the position on a color coordinate.

FIG. 5 is a graph showing the thermal budget applied when manufacturing a high power white LED device including a two-step curing process.

The present invention relates to a light emitting diode (LED) device, and more particularly to a high output white light emitting diode device.

An LED device is a kind of semiconductor device that converts electrical energy into light energy using characteristics of a compound semiconductor. LED devices can be divided into blue LED devices, white LED devices, 7-color LED devices, or pastel color LED devices according to the color characteristics of the emitted light. Doing. Among these, white LED devices are currently used for the back light of liquid crystal displays (LCDs) used in high-brightness light sources for flash and portable electronic products (mobile phones, camcorders, digital cameras and personal digital assistants (PDAs), etc.). Light source, light source for electronic board, light source for lighting and switch light source, light source for indicator light and traffic signal, etc., the range of use is getting considerably wider. In particular, the range of use of high power white LED element with rated current of several hundred mA to 720mA or more is expanded. It is becoming.

The white LED device is a device that emits white light as a whole by fluorescence conversion of a part of the light generated from the LED chip to light of a longer wavelength, and finally emits light of two wavelengths that are complementary to each other. More specifically, an LED chip is a semiconductor device that forms a PN junction with a compound such as GaAsP, GaAlAs, GaP, InGaAlP, or GaN, and when a predetermined voltage is applied to the PN junction, electrons or holes move to couple with excess holes or electrons. When light energy is emitted. The emitted light energy is light of a monochromatic wavelength, and is classified into a blue LED chip or an ultraviolet LED chip according to the emission wavelength. Then, part of the light emitted from the LED chip, for example, blue light, is transferred to yellow light by the phosphor and is emitted. Finally, blue light and yellow light are mixed to make white light appear to be emitted to the outside of the LED device.

There are many factors that affect the characteristics of the white light emitted from the white LED device. For example, the characteristics of the emitted light due to the intensity of the emitted light from the LED chip, the combination of the emitted light from the LED chip and the light converted by the phosphor, the component, the content of the phosphor, and / or the state in which the phosphor is dispersed in the epoxy resin, etc. Is affected.

Conventional high power white LED devices use blue LED chips and phosphors emitting yellow light, and yttrium-aluminum-garnet (Y ₃ Al ₅ O ₁₂ : Ce, YAG) compounds are generally used as yellow phosphors.

The emitted light of the high power white LED device according to the prior art is composed of two types of peaks: a narrow peak in the blue wavelength region and a wide peak in the yellow wavelength region. This is because the white LED device according to the prior art includes only a phosphor for converting blue light into yellow light. As a result, since the white light emitted from the white LED device according to the prior art is a mixture of two wavelengths of light that are not in a completely complementary relationship, there is a problem that cannot be recognized as white light close to natural light as a whole. In the case of the high power white LED device according to the prior art, the luminance was only about 600 mcd.

In addition, since the high power white LED device according to the prior art uses a combination of two wavelengths of light, the spectrum of the white light is remarkably different according to the intensity in the yellow wavelength region. Therefore, the manufacturing process is difficult because the amount of YAG phosphor added must be precisely controlled. In addition, since the YAG phosphor is used, there is a limit in obtaining luminance as much as that required for a high output LED device. In addition, since only one phosphor is used, there is a disadvantage that it is not easy to manufacture a large amount of uniform white LED device having excellent optical characteristics.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a high output white LED device emitting white light close to natural light and a method of manufacturing the same.

Another technical problem to be achieved by the present invention is to provide a high output white LED device having a large process margin and easy to mass produce a uniform product, and a method of manufacturing the same.                         

Another object of the present invention is to provide a high output white LED device having high brightness and excellent optical characteristics and a method of manufacturing the same.

High power white LED device according to an embodiment of the present invention for achieving the above technical problem is configured to include a high power blue LED chip, LED chip mounting member, a mold resin and a yellow green phosphor and a green phosphor. The LED chip mounting member includes an external connection terminal, and a predetermined wiring pattern electrically connected to the external connection terminal is formed on and / or inside the member. The LED chip is mounted on the LED chip mounting member. The LED chip is electrically connected to the external connection terminal through the wiring pattern and has a high output current of about 500 to 720 mA. And the resin for mold seals the said LED chip. The yellow green and the green phosphor are evenly dispersed in the mold resin, and the light emitted from the LED chip, the yellow green phosphor, and the green phosphor combine with each other to form white light.

According to one aspect of the above embodiment, the yellow green phosphor may be a YAG phosphor, and the green phosphor may be an Sr _1-x S _x : Eu phosphor. In addition, the YAG phosphor may have a peak emission wavelength of between 545 and 555 nm, and the Sr _1-x S _x : Eu phosphor may have a peak emission wavelength of between 520 and 540 nm. In this case, the YAG phosphor and the Sr _1-x S _x : Eu phosphor occupy 5 to 60% by weight of the mold resin, and the YAG phosphor is the YAG phosphor and Sr _1-x S _x : Eu. May comprise 1-30% by weight of the combined weight.

According to another aspect of the above embodiment, the mold resin is composed of a first mold resin and a second mold resin formed on the first mold resin, and the YAG phosphor is used for the first mold. The Sr _1-x S _x : Eu phosphor is dispersed in the resin, and the second mold resin is dispersed.

According to an aspect of the present invention, there is provided a method of manufacturing a high output white LED device according to an embodiment of the present invention. First, an LED having a predetermined wiring pattern having an external connection terminal and electrically connected to the external connection terminal is formed. A chip mounting member is prepared. A high output blue LED chip is mounted on the LED chip mounting member and attached thereto, and the LED chip is electrically connected to the external connection terminal through the wiring pattern. In addition, a YAG phosphor and a Sr _1-x S _x : Eu phosphor are mixed in a mold resin to prepare a mother resin dispersed therein, wherein the light emitted from the LED chip, the yellow green phosphor, and the green phosphor is prepared. Prepares a mother resin that combines with each other to form white light, and then molds the LED chip with the mother resin using an encapsulation process.

According to one aspect of the above embodiment, the step of preparing the base resin, the liquid epoxy resin containing the main material and the curing agent at room temperature is primarily mixed, under a temperature of 70 to 100 ℃ and 1 to 30 Torr Performing a first curing process of semi-curing the liquid epoxy resin, and then adding the YAG phosphor and the Sr _1-x S _x : Eu phosphor to the semi-cured liquid epoxy resin at room temperature and mixing the mixture in a second manner. The molding may include applying a second resin to apply the mother resin on the LED chip and to cure the mother resin under a temperature and a normal pressure of 120 ° C. or higher.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals denote like elements throughout the specification.

1A and 1B are schematic cross-sectional views of a high power white LED package according to an embodiment of the present invention, in which FIG. 1A is a lamp type LED device and FIG. 1B is a chip type LED device. Although the lamp type and chip type LED elements are shown in the present embodiment, the present embodiment can be equally applied to the top type LED element (see FIG. 1C).

1A and 1B, the high power white LED device is a high power LED chip 14, a member 20 or 24 that can be mounted by attaching the LED chip 14, and a mold for enclosing the LED chip 14. And the phosphors 11 and 12 evenly dispersed in the resin 10 and the mold resin 10. The phosphors 11 and 12 are composed of two phosphors of yellow green and green. In the present embodiment, the two phosphors 11 and 12 are mixed with each other and randomly dispersed in the resin for a mold. The structure of the LED device has almost no difference in the structure of the high-power LED device according to the prior art, except that two kinds of phosphors, yellow green and green, are included. For example, a lead frame, a printed circuit board, or the like can be used as the LED chip mounting members 20 and 24. When the lead frame is used as an LED chip mounting member, the external lead 22 serves as an external connection terminal connected to an external electrode, and the external lead 22 is disposed on the LED chip mounting member 24. It is electrically connected to the LED chip 14 via the formed wiring pattern (not shown). When the printed circuit board is used as the LED chip mounting member, various patterns of wiring patterns are formed on the surface and the inside of the printed circuit board, and external connection terminals may be formed on the back or edge of the printed circuit board. As such, since the basic configuration and operation of the LED device according to the embodiment of the present invention are almost similar to the configuration or operation of the LED device according to the prior art, detailed description thereof will be omitted herein. Reference numeral 16, not described in FIGS. 1A and 1B, is an adhesive, 18 is a bonding wire, and 26 is a molder cup.

Figure 1c is a schematic cross-sectional view of a tower high power white LED device according to another embodiment of the present invention. The LED device according to the present embodiment is different from the LED device (see FIGS. 1A and 1B) according to the above-described embodiment in that it has a double mold structure. That is, the LED device according to the present embodiment is separated from each other by the first mold in which the yellow green phosphor is dispersed and the second mold in which the green phosphor is dispersed, rather than the yellow green phosphor and the green phosphor being mixed together. It is characterized by. Although only a top LED element is shown in FIG. 1C, a high output white LED element composed of a double mold may be equally applied to a lamp type LED element (see FIG. 1A) or a chip type LED element (see FIG. 1B).

An LED device including such a double mold and a method of manufacturing the same are disclosed in Korean Patent Application No. 2004-0000094 filed on January 2, 2004, by the same person as the applicant of the present patent, "White light emitting diode device composed of a double mold and It is described in detail in "Method for Producing It. The above patent application is hereby incorporated by reference in its entirety. Hereinafter, a high power white LED device composed of a double mold will be briefly described.

Referring to FIG. 1C, the high output white LED device includes an LED chip mounting member 24, a high output blue LED chip 14, first molds 10a and 11, and second molds 10b and 12. . The first molds 10a and 11 are composed of a resin 10a for a mold and a yellow green phosphor 11 evenly dispersed therein. The second molds 10b and 12 are composed of a mold resin 10b and green phosphors 12 evenly dispersed therein. In FIG. 1C, although the second molds 10b and 12 are formed on the first molds 10a and 11, the positions of the first molds 10a and 11 and the second molds 10 and 12 may be interchanged. .

However, experiments show that the optical properties of the LED device are better in the former case among the two cases. That is, in the case of the double mold LED device composed of the first molds 10a and 11 and the second molds 10b and 12, the fluorescent resin having a relatively long emission wavelength, i. The green phosphor 11 is uniformly dispersed, and the resin 12b having a relatively short emission wavelength, that is, the green phosphor 12 is evenly dispersed in the mold resin 10b disposed above, in terms of optical characteristics. desirable.

As described above, in the high output white LED device having the double mold, the first molds 10a and 11 should set the height h ₁ of the first molds 10a and 11 thicker than at least the height of the top surface of the LED chip 14. In addition, the height h ₁ of the first molds 10a and 11 is about 10-90% of the height h ₁ + h ₂ of the sum of the first molds 10a and 11 and the second molds 10b and 12. It is preferable that it is about degree.

The high power white LED device according to the embodiment of the present invention as described above with reference to FIGS. 1A to 1C has the following features.

First, a high output blue LED chip 14 is used to emit high brightness white light from the LED device. The type of blue LED chip 14 that can be used is appropriately selected in consideration of the characteristics of the phosphor, that is, the range of the wavelength at which the phosphor is excited and the peak wavelength range of the emitted white light. For example, in the case of using the yellow green phosphor 11 and the green phosphor 12, it is preferable to use the blue LED chip 14 having an emission peak wavelength in the range of 425-475 nm.

Second, in this embodiment, two kinds of phosphors 11 and 12 are used to manufacture LED devices emitting white light. Therefore, the LED device according to the embodiment of the present invention has a large process margin. In addition, these two phosphors 11 and 12 have different emission peak wavelengths from each other. Therefore, in the LED device according to the embodiment of the present invention, the light of the intrinsic emission wavelength of the LED chip 14 and the light of three peak wavelengths, such as the wavelength emitted by the fluorescence conversion from each of the phosphors 11 and 12, are combined. Therefore, the emitted light shows white light closer to natural light.

One of the two phosphors described above is a yellow green phosphor. As the yellow green phosphor, a YAG phosphor 11 may be used. The YAG phosphor 12 may include, for example, Y, Al, and O, and may further include Ce. The YAG phosphor 11 used in this embodiment absorbs light of about 400-480 nm (maximum excitation wavelength is 440 nm) and emits yellow green light having a peak wavelength of about 550 nm. As described above, the maximum excitation wavelength and the peak wavelength may vary slightly depending on the composition of the phosphor 11, but do not deviate significantly from the value.

FIG. 2A shows a graph measuring the spectrum of light emitted from the tower high power LED device including only the YAG phosphor 11. Here, a high output blue LED chip having an emission wavelength of 470 nm was used as the LED chip. As the YAG phosphor 11, Y was about 29.6 wt%, Al was about 15.1 wt%, O was about 53.1 wt% and Ce was about 2.2 wt%, and the excitation peak wavelength of the phosphor 11 was about 440 nm. Referring to FIG. 2A, it can be seen that yellow-green light having a peak wavelength of about 553 nm is emitted from the YAG phosphor 11 with respect to blue emission light having a 470 nm peak wavelength.

The other phosphor among the above-described phosphors is the green phosphor 12. As the green phosphor, Sr _1-x S _x : Eu phosphor 12 may be used. Here, x is between about 0.3-0.7, and europium (Eu) serves as an ion for activating SrS. In addition, the Sr _1-x S _x : Eu phosphor 12 may further include Ga, Mo, or the like. The Sr _1-x S _x : Eu phosphor 12 used in the present embodiment absorbs light of about 400-500 nm (the maximum excitation wavelength is 450 nm) and emits green light having a peak wavelength of about 540 nm. The maximum excitation wavelength and the peak wavelength may vary slightly depending on the composition of the phosphor 12, but do not deviate greatly from the value.

FIG. 2B shows a graph measuring the spectrum of light emitted from the tower LED device including only the Sr _1-x S _x : Eu phosphor 12. Referring to FIG. 2B, it can be seen that a blue LED chip having emission wavelengths of 460 nm and 470 nm, respectively, is used as the LED chip. And Sr _1-x S _x : Eu phosphor 11 having about 21 wt% Sr, about 23.5 wt% S, about 37.7 wt% Ga, about 15.3 wt% Mo and about 2.5 wt% Eu. Was used. The excitation wavelength of the Sr _1-x S _x : Eu phosphor 11 described above is about 420 nm to 470 nm, and the peak excitation wavelength is about 450 nm. The emission wavelength of the Sr _1-x S _x : Eu phosphor 11 is about 540 nm. Therefore, it can be seen that the Sr _1-x S _x : Eu phosphor 11 absorbs light having a wavelength of about 420 to 470 nm and emits green light having a peak wavelength of about 540 nm.

The high power white LED device according to the embodiment of the present invention including the yellow green phosphor 11 and the green phosphor 12 emits white light in the following manner. That is, some of the blue light emitted from the LED chip 14 is absorbed into the YAG phosphor 11 and the Sr _1-x S _x : Eu phosphor 12, respectively, but the remaining portion is directly outside the mold resin 10. Is released. When blue light is absorbed by the YAG phosphor 11, the YAG material is excited with the help of Ce, and then returns to a stable state to emit fluorescence-converted yellow green light, and blue light is absorbed by the Sr _1-x S _x : Eu phosphor 12. With the aid of Eu, Sr _1-x S _x is excited and then returns to a stable state and emits fluorescence-converted green light. Depending on the x value, the peak wavelengths of the fluorescence-converted yellow green light and green light may vary slightly, but when x is in the range of 0.3-0.7, there is no significant effect on the characteristics of the emitted light. As a result, the blue light emitted without being absorbed by the phosphors 11 and 12 and the yellow green and green series light emitted from the YAG phosphor 11 and the Sr _1-x S _x : Eu phosphor 12 are combined, The LED device ultimately emits white light.

3 shows an emission spectrum of white light emitted from a top LED element comprising an LED chip 14, a YAG phosphor 11, and a Sr _1-x S _x : Eu phosphor 12 at a wavelength of 440 nm.

Of the light emitted from the LED chip 14, the amount of light absorbed by the phosphors 11 and 12 and the amount of light emitted as it is, and the amount of light absorbed by the phosphors 11 and 12 are YAG phosphors 11 and Sr _1-x. S _x : The amount of yellow green light and green light absorbed and emitted by the Eu phosphor 12 depends on the amount and composition of the phosphors 11 and 12 dispersed in the mold resin 10 and the dispersion uniformity of the phosphors 11 and 12. Therefore, it may vary. The optical properties of the high power white LED device are affected by the amount, composition, and dispersion uniformity of the phosphors 11 and 12.

In order to manufacture LED devices having excellent optical properties, the phosphors 11 and 12 may occupy about 2 to 45% by weight and preferably 6 to 8% by weight of the mold resin 10. More specifically, in the case of an LED device manufactured using a liquid epoxy resin in which phosphors are mixed, such as a potting method or a screen pattern mask method, the phosphors 11 and 12 are about 2 to the weight of the resin 10 for a mold. -40% by weight, more preferably about 4-30% by weight. In the case of an LED device manufactured using a solid epoxy resin tablet mixed with phosphors, such as transfer molding, the phosphors 11 and 12 are about 5 to 45% by weight, more preferably about 5 to 40% by weight. It may be within range. In addition, the green phosphor Sr _1-x S _x : Eu phosphor 12 may account for about 1 to 30% by weight, more preferably about 3 to 15% by weight, based on the total weight of the phosphors 11 and 12. .

4 is a color coordinate of a high power white LED device including only a YAG phosphor prepared according to the prior art and a high power white LED device including a YAG phosphor prepared according to an embodiment of the present invention and an Sr _1-x S _x : Eu phosphor. The position of the phases is shown in comparison. Here, Sample No. 1 is for the LED chip, Sample No. 2-4 is for the LED element including only the YAG phosphor, and Sample No. 5-7 is the ratio of Sr _1-x S _x : Eu phosphor to the entire phosphor. For an LED device with 5% by weight relative to sample and Sample Nos. 8-10 for an LED device with a ratio of Sr _1-x S _x : Eu phosphors at 10% by weight relative to the entire phosphor. And sample numbers 2-4, 5-7, and 8-10 are the cases where the ratio of the fluorescent substance with respect to resin for molds is 6 weight%, 8 weight%, and 10 weight%, respectively.

Referring to FIG. 4, it can be seen that a high power blue LED chip having an emission wavelength of 440 nm is used (sample number 1), and the ratio of Sr _1-x S _x : Eu phosphor is 5% by weight, It can be seen that the ratio is close to the white coordinate (x = 0.31, y = 0.31) when the ratio is about 7% by weight.

In addition, Table 1 shows the measurement of the luminance and the position on the color coordinates of the emitted light of the LED elements of the sample Nos. 5 and 6 among the above samples. In the experiment, the top LED device was used, but a single mold was used instead of the double mold. Referring to Table 1, it can be seen that in the case of sample number 5, the position on the CIE chromaticity diagram of the emitted light is x = 0.279, y = 0.281, and in the case of sample number 6, the position on the CIE chromaticity diagram of the emitted light is x = 0.305. , y = 0.333. In addition, it can be seen that the luminance in the case of Sample Nos. 5 and 6 is about 730 mcd and 790 mcd, respectively, much larger than about 600 mcd, which is the luminance of the high-power white LED device according to the prior art. In addition, the high output white LED device according to the present invention has a long life of about 100,000 hours or more.

Ratio of phosphor to resin for mold Luminance (mcd) CIE, x coordinate CIE, y coordinate 6% by weight 729.4 0.279 0.281 8% by weight 789.4 0.305 0.333

Third, the high output white LED device according to the present invention can be manufactured so that the phosphors 11 and 12 are evenly dispersed in the resin 10 for a mold. The phosphors 11 and 12 uniformly dispersed in the mold resin 10 significantly affect the emission light characteristics from the LED element. In general, since the phosphor has a specific gravity larger than that of the epoxy resin, when the phosphor is mixed in the liquid epoxy resin, it tends to precipitate. However, in order to manufacture a white LED element with little color dispersion, it is preferable that the phosphors 11 and 12 are evenly distributed in the resin 10 for a mold. As disclosed in Korean Patent Application No. 2003-0084173 filed on Nov. 25, 2003 by the same applicant as the applicant of the present invention, a method of manufacturing a white light emitting diode device including a two-step curing process, a two-step curing process In this case, it is possible to manufacture an LED device in which two kinds of phosphors 11 and 12 are evenly dispersed in the mold resin 10. The patent application specification is hereby fully incorporated by reference.

Hereinafter, a method of manufacturing a high output white LED device including a two-step curing process will be briefly described. However, the manufacturing method of the high output white LED device according to the present invention is not limited to the manufacturing method using a two-step curing process. That is, the LED device according to the present invention can also be manufactured by using a known method of manufacturing an LED device. For example, the molding process may be performed by a potting method or a screen pattern mask method using a mother resin containing the yellow green phosphor 11 and the green phosphor 12 that have not undergone the two-step curing process, or the yellow green phosphor 11 and the green The LED device may be manufactured by performing a molding process by a transfer molding method using a tablet of the mother resin including the phosphor 12. In the present specification, the 'base resin' refers to the composition of the phosphors 11 and 12 and the epoxy resin 10, which are in a state before being coated or molded on the LED chip.

FIG. 5 is a graph showing the thermal budget applied when fabricating a high power white LED device comprising a two-stage curing process.

Referring to FIG. 5, first, a main epoxy and a curing agent are mixed first to prepare a liquid epoxy resin. Some of the phosphors 11 and 12 may be further added in the primary mixing step. However, no further silicone resin or EMC powder and filler are added in the primary mixing process. The subject may be, for example, one of cresol novolac epoxy, petroleum novolac epoxy or bisphenol A epoxy or a mixture thereof. In addition, the curing agent may be one of an anhydride, an aromatic amine modified product, or a phenol novolox epoxy, or a mixture thereof. If necessary in the primary mixing step, a curing accelerator such as an imidazole compound or an amine compound may be further added to promote the curing reaction.

Subsequently, a primary curing step is performed on the liquid epoxy resin. The first curing process is performed for a predetermined time t ₄ -t ₁ . The temperature and time of the first cure step are mutually dependent, in particular the heating time at temperature T ₁ may vary depending on the heating temperature of the liquid epoxy resin. For example, when the temperature T ₁ is about 70-100 ° C., the temperature increase time t ₂ -t ₁ may be about 30 minutes. In FIG. 5, T ₀ represents room temperature. The first curing process is carried out in a low pressure state, but the reason for performing the process in a low pressure state is to prevent bubbles from occurring. The low pressure may be about 1-30 torr. As a result of the above first curing process, the liquid epoxy resin is aged into an epoxy resin in a semi-cured state.

Subsequently, referring to FIG. 5, a mother resin is produced by performing a second mixing step with respect to the semi-cured epoxy resin. The 2nd mixing process is a process for making the raw material of semi-hardened epoxy resin mix better. In the case where the phosphors 11 and 12 are added in the first mixing step, the phosphors are also mixed at this time. In the second mixing step, the required amounts or insufficient amounts of the phosphors 11 and 12 are added. For example, based on the weight of the resin for a mold, the weight of the phosphors 11 and 12 may be about 2 to 45% by weight, preferably 6 to 8% by weight. The green phosphor 12 may be about 1-30% by weight, preferably 3-15% by weight, based on the weight of the phosphors 11, 12. The second mixing process is performed at room temperature (T ₀ ), and there is no particular limitation on the process time (t ₅ -t ₄ ).

Next, the LED chip is encapsulated using the mother resin in which the second mixing process is completed. Here, the LED chip is attached to and mounted on the LED chip mounting member using a conductive or nonconductive adhesive. In addition, if necessary, the wire bonding process is completed and electrical connection to the LED chip is completed. As the sealing step, for example, as described above, a potting method or a screen pattern mask method can be used.

Subsequently, referring to FIG. 5, a second curing process of heat-treating the resultant to which the matrix resin is applied is performed. The second curing step is a step for completely curing the parent resin. The second curing process can also be carried out at normal pressure, and is carried out for a predetermined time t ₇ -t ₆ at a temperature T ₂ higher than the temperature T ₁ of the first curing process. For example, the heating step of the second curing process may be carried out at a temperature of about 120-130 ° C. for about 1-2 hours. More specifically, the second curing process includes a temperature raising step (t ₆ -t ₅ ) of about 30 minutes, a heating step (t ₇ -t ₆ ) of about 1 hour at a temperature of about 130 ° C., and a temperature reduction step of about 30 minutes ( t ₈ -t ₇ ). In the second curing process, the heating time and the heating temperature are mutually dependent.

In the case of this two-step curing process, since the width of the epoxy resin decreases significantly during the second curing process, which is the final heating step, the phosphor precipitates under the mold resin such as epoxy resin. You can prevent it. As a result, since the two phosphors are evenly dispersed in the mold resin, a high output white LED device having less color dispersion and excellent optical characteristics can be produced.

Fourth, the high power white LED device according to the present invention uses not only one YAG phosphor but also a green phosphor. Therefore, it is not only easy to manufacture LED devices that emit light close to natural light white than the case of using only one YAG phosphor to manufacture a white LED device, but also a much larger process margin because two phosphors are used.

According to the present invention, since the blue light and the yellow green phosphor emitted from the LED chip and the green light and the yellow green light fluoresced by the Sr _1-x S _x : Eu phosphor are combined, respectively, white light closer to natural light than in the prior art. It is possible to make a high power white LED device that emits light.

In addition, according to the present invention, since a high output white LED device using two phosphors is manufactured, the process margin is large, and it is easy to produce a uniform product in large quantities.

In addition, the high power white LED device manufactured according to the present invention has high luminance and excellent optical characteristics as compared with the high power white LED device according to the prior art.

Claims (7)

An LED chip mounting member having an external connection terminal and having a predetermined wiring pattern electrically connected to the external connection terminal; A high output blue LED chip mounted on the LED chip mounting member and electrically connected to the external connection terminal through the wiring pattern; A resin for a mold encapsulating the LED chip; A light emitting diode device comprising: a yellow green phosphor and a green phosphor dispersed evenly in the mold resin, wherein the light emitted from the LED chip, the yellow green phosphor, and the green phosphor combine with each other to form white light. In the high output white light emitting diode device, The yellow green phosphor is a YAG phosphor, the green phosphor is an Sr _1-x S _x : Eu phosphor, The mold resin is composed of a resin for a first mold and a resin for a second mold formed on an upper portion of the resin for a first mold, The YAG phosphor is dispersed in the resin for the first mold, the Sr _1-x S _x : Eu phosphor is dispersed in the resin for the second mold, The YAG phosphor has a peak emission wavelength of 545-555 nm, and the Sr _1-x S _x : Eu phosphor has a peak emission wavelength of 520-540 nm. delete delete delete The method of claim 1, The YAG phosphor and the Sr _1-x S _x : Eu phosphor account for 5 to 60% by weight of the mold resin; The YAG phosphor occupies 1 to 30% by weight of the total weight of the YAG phosphor and the Sr _1-x S _x : Eu phosphor. Preparing an LED chip mounting member having an external connection terminal and having a predetermined wiring pattern electrically connected to the external connection terminal; Mounting and attaching a high power blue LED chip on the LED chip mounting member; Electrically connecting the LED chip and the external connection terminal through the wiring pattern; Preparing a mother resin in which a YAG phosphor and an Sr _1-x S _x : Eu phosphor are mixed in a resin for molding and dispersed therein, wherein the light emitted from the LED chip, the yellow green phosphor, and the green phosphor A mother resin preparation step of combining with each other to form white light; A method of manufacturing a high power white light emitting diode device comprising molding the LED chip with the matrix resin using an encapsulation process. The matrix resin preparation step, Primarily mixing a liquid epoxy resin containing a main agent and a curing agent at room temperature, A first curing step of semi-curing the liquid epoxy resin at a temperature of 70 to 100 ° C. and a pressure of 1 to 30 torr, And adding the YAG phosphor and the Sr _1-x S _x : Eu phosphor to the semi-cured liquid epoxy resin at room temperature and mixing the mixture in a second manner. The method of claim 6, The molding step, Applying the matrix resin on the LED chip; And And a second curing step of curing the parent resin at a temperature of 120 to 130 ° C. and atmospheric pressure.

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