CN103178194B - A kind of large power white light LED encapsulating structure and preparation method thereof - Google Patents

Abstract

The invention provides a packaging structure of high-power white light LED. Through the first spin coating, a layer of inner fluorescent glue mixed with small particle fluorescent powder is coated on the upper surface and side wall of the LED chip, and after drying , and then use the automatic dispensing machine to spray dots, and apply a layer of outer fluorescent glue mixed with super-large particle phosphor powder on the upper surface of the inner fluorescent glue and the corresponding local position above the LED chip. The present invention makes use of the property that the outer layer of fluorescent glue is not easy to infiltrate the dried inner layer of fluorescent glue, so that the outer layer of fluorescent glue forms a convex hull only at the corresponding local position above the LED chip. The present invention can use ultra-large particle phosphor without adding diffusing agent, etc., which not only improves the light efficiency to a great extent, but also prevents the phosphor powder from being deposited on the side of the LED chip to produce a yellow circle phenomenon.

Description

A high-power white light LED packaging structure and preparation method thereof

technical field

The invention relates to a high-power white light LED packaging structure and a preparation method thereof, belonging to the technical field of semiconductor light emitting device manufacturing.

Background technique

With the continuous improvement of LED epitaxial materials and chip levels, white LEDs have achieved great development due to their advantages of small size, long life, green environmental protection, and being able to meet the requirements of various harsh environments, and power white LEDs have become an important solid-state lighting. One of the light sources, its packaging technology has also been unprecedentedly developed. However, there are still many problems in the packaging of power-type white light LEDs. The first is that the luminous efficiency is still not high, and the second is that the emission spectrum is not uniform. For example, after the blue light chip excites the phosphor powder of the corresponding wavelength, there are yellow circles and blue circles due to poor light mixing caused by factors such as phosphor particle precipitation. Power-type white light LEDs are generally obtained by encapsulating larger particle phosphor powder excitation methods, and usually need to be mixed with a diffusing agent to prevent precipitation of the phosphor powder and obtain a better spectrum, but the incorporation of diffusing agents usually seriously affects the size of the luminous flux. Makes the light efficiency drop sharply.

Chinese patent CN101404317A discloses a high-power white LED packaging method. After the LED chip is solidified in the base and the wire is baked, transparent silica gel is placed in the base so that the transparent silica gel covers the LED chip, and then the entire LED chip is covered with a lens. The base, and then fill the cavity formed by bonding the lens and the base from the small hole of the side ear on the edge of the lens with fluorescent glue. Finally, the consistency of LED light color is improved, but compared with other technical patents, this patent has no obvious effect on improving light efficiency.

Chinese patent CN101369623A provides a process for coating fluorescent powder on LED chips. After mixing the fluorescent powder and glue according to a certain ratio, it is baked and cured through multiple coatings until the liquid in the bowl and cup is cured. The surface is flush with the upper edge of the bowl and there are no dents. Effectively solve the phenomenon of phosphor powder precipitation and aggregation during one-time coating and curing of phosphor powder. Chinese patent CN101714598A discloses a method for layering and precipitating fluorescent powder in the packaging process of white light LEDs. Additives, yellow fluorescent powder, and silica gel are evenly mixed in a certain proportion for degassing treatment, and the material is filled into white LED high-power bracket bowl cups. After keeping it for 2 hours, bake it in sections, and keep it at 70°C, 90°C, 110°C, and then 150°C for 1 to 2 hours respectively to make white LED products. The invention intentionally adopts the method of layered precipitation, so that the fluorescent powder can be deposited uniformly, and the problem of poor product consistency can be effectively improved. Baking the phosphor powder through multiple coatings or baking in sections can improve the aperture and enhance the uniformity of the product to a certain extent, but at the same time it often introduces layering of the phosphor powder, and still cannot obtain high light efficiency and High uniformity white LED.

Chinese patent CN101661987A discloses a white LED packaging structure and its packaging method. The method is to first coat the LED chip with a heat-insulating transparent material layer, and then coat the heat-insulating transparent material layer with a phosphor layer. For the heat dissipation problem of power white light LED, a layer of heat-insulating transparent material layer is first coated on the chip surface to play the role of heat insulation. The structure of the formed transparent material layer and phosphor layer is a lens structure, or a lens structure is arranged on the phosphor layer. The structure of the phosphor layer is as follows: a layer of red phosphor layer is first in contact with the heat-insulating transparent material layer, and then a layer of YAG phosphor layer is coated on the outside of the red phosphor layer, so that a stable color rendering quality can be obtained. High power white LED.

Chinese patent CN102185087A discloses a high-power LED packaging structure, which uses a large particle mixed with small particle phosphor, so that the coated fluorescent glue is larger than the side of the chip, forming an arc consistent with the arc of the covered lens. The coated fluorescent glue is mixed with small particles in large particles, and the radius and dosage of the large and small particles meet a certain proportional relationship. Adding small particles into large particles can improve the quality of light and color to a certain extent, but because the coating is completed at one time, the coating height is greater than the side of the chip, so that a large amount of phosphor is still deposited on the side of the chip, which cannot be avoided. The reappearance of the yellow circle phenomenon.

Contents of the invention

Summary of the invention:

Aiming at the deficiencies of the prior art, the present invention provides a packaging structure of high-power white light LED. Through the first spin coating, a layer of inner surface mixed with small particle phosphor powder is coated on the upper surface and side wall of the LED chip. A layer of fluorescent glue, after drying, spray it with an automatic glue dispenser, and coat a layer of outer fluorescent glue mixed with super-large particle phosphor powder on the upper surface of the inner layer of fluorescent glue and the corresponding local position above the LED chip. The present invention makes use of the property that the outer layer of fluorescent glue is not easy to infiltrate the dried inner layer of fluorescent glue, so that the outer layer of fluorescent glue forms a convex hull only at the corresponding local position above the LED chip. The present invention can use super-large-grained phosphor powder without adding diffusing agent, etc., which not only greatly improves the light efficiency, but also avoids the technical deficiency of yellow circle phenomenon caused by a large amount of phosphor powder deposited on the side of the LED chip.

The present invention also provides a preparation method of the above high-power white LED packaging structure.

Terminology Explanation:

LED: LightEmittingDiode, light emitting diode.

Technical scheme of the present invention is as follows:

A high-power white LED packaging structure, including a bottom-up LED high-power bracket, a reflective bowl, a blue LED chip, fluorescent glue, transparent silica gel and a lens; the reflective bowl is set on the LED high-power bracket , the blue LED chip is set in the reflective bowl through conductive silver glue or high thermal conductivity insulating glue; the blue LED chip is electrically connected to the LED high-power bracket through gold wire; Covered with an inner layer of fluorescent glue and an outer layer of fluorescent glue, the size of the phosphor particles contained in the inner layer of fluorescent glue is smaller than that of the phosphor particles contained in the outer layer of fluorescent glue; the coating range of the inner layer of fluorescent glue is the entire blue LED chip and the bottom surface of the exposed reflective bowl, the thickness of the inner layer of fluorescent glue on the bottom surface of the reflective bowl is smaller than the thickness of the blue LED chip; the outer layer of fluorescent glue completely covers the upper surface and side walls of the blue LED chip, showing a convex Bulb-shaped, the radius of the bottom surface of the convex-hull-shaped outer layer of fluorescent glue is smaller than the radius of the bottom surface of the inner layer of fluorescent glue; a lens is arranged above the LED high-power bracket, and the lens is filled with transparent silica gel.

The more phosphor powder in the blue LED chip from outside the side wall to the edge of the reflective bowl, the easier it is to produce apertures. In order to effectively avoid the occurrence of apertures, this application sets as few phosphors as possible outside the chip. In order to avoid the precipitation of phosphor particles when coating the inner layer of fluorescent glue, the phosphor particles with smaller particles are used in the inner layer of fluorescent glue; in order to improve the light efficiency, larger phosphor particles are used in the outer layer of fluorescent glue in this application particles.

The fluorescent glue in the inner layer is formed by mixing phosphor particles and transparent silica gel at a mass ratio of 1:7-1:5, and the particle size range of the phosphor particles is 7-13 μm.

Preferably, the fluorescent glue in the inner layer has a mass ratio of phosphor particles to transparent silica gel of 1:6;

The fluorescent glue in the outer layer is formed by mixing phosphor particles and transparent silica gel at a mass ratio of 3:10, and the particle size range of the phosphor particles is 20-23 μm.

The refractive index of the transparent silica gel is 1.5.

The thickness of the inner layer of fluorescent glue is greater than 1/2 of the thickness of the blue LED chip and less than the thickness of the blue LED chip, and the height of the upper surface of the convex outer layer of fluorescent glue is lower than or equal to Reflects the top edge of the bowl.

The size range of the blue LED chip is 24-50mil.

The lens is a polycarbonate lens (PC lens).

A method for preparing the above-mentioned high-power white light LED packaging structure, the method steps are as follows:

1) Solid crystal, wire bonding: Use conductive silver glue or high thermal conductivity insulating glue to fix the blue LED chip in the reflective bowl, and cure and bake at 150℃～180℃ for 60～90min, and then use gold wire to fix the blue LED chip. The chip is welded on the LED high-power bracket;

2) Prepare the fluorescent glue for the inner layer: mix and stir the fluorescent powder particles with a particle size of 7-13 μm and the transparent silica gel at a mass ratio of 1:5-1:7, and heat and defoam in a vacuum box to form the fluorescent glue for the inner layer ;

3) Coat the inner layer fluorescent glue prepared in step 2) on the blue LED chip by spin coating, and cure and bake at 150°C for 10-15 minutes; after baking, the appearance structure of the inner layer fluorescent glue distribution is shown in Figure 2 shown;

4) Prepare the outer layer fluorescent glue: mix and stir the phosphor particles with a particle size of 20-23 μm and the transparent silica gel at a mass ratio of 3:10, and heat and defoam in a vacuum box to form the outer layer fluorescent glue;

5) Spray the outer layer of fluorescent glue prepared in step 4) on the upper surface of the inner layer of fluorescent glue after curing and baking in step 3) by automatic dispensing, facing the blue LED chip, and immediately bake it at 140-160°C Bake for 3-7 minutes, then transfer to 110-130°C and bake for 20-40 minutes to form a convex hull shape enveloping the blue LED chip, that is, to make a semi-finished white LED; The characteristics of infiltration between the fluorescent glue in the inner layer are not easy to occur, and finally the distribution structure of the fluorescent glue is obtained, as shown in Figure 3;

6) For the semi-finished white light LED prepared in step 5), cover the lens, fill the lens with transparent silica gel, bake at 90-110° C. for 1-1.5 h to cure, and obtain a high-power white light LED.

Preferably, in the step 2) when preparing the inner fluorescent glue: the fluorescent powder particles and the transparent silica gel are mixed and stirred evenly in a mass ratio of 1:6.

Preferably, the refractive index of the transparent silica gel is 1.5.

After step 3) curing and baking, the thickness of the inner fluorescent glue is greater than 1/2 of the thickness of the blue LED chip and less than the thickness of the blue LED chip; step 5) the convex hull-shaped outer The height of the upper surface of the layer of fluorescent glue is lower than or equal to the upper edge of the reflective bowl.

The size range of the blue LED chip is 24-50mil.

The lens is a polycarbonate lens (PC lens).

The advantages of the present invention are:

The present invention uses two different coating processes to coat the fluorescent glue, so that the precipitation of the fluorescent powder on the side of the LED chip is significantly reduced: the particle size of the fluorescent powder in the fluorescent glue coated twice is different, and the ratio of powder and glue is different , and then the large particle phosphor is mainly concentrated on the upper surface of the LED chip. Under the premise of not using a diffusing agent, the present invention can effectively prevent the generation of yellow circles, ensure the uniformity of the spectrum, and improve the luminous efficacy of high-power white LEDs.

Description of drawings

Fig. 1 is a schematic diagram of the distribution structure of fluorescent glue in the existing power type white light LED packaging;

Fig. 2 is a schematic diagram of the distribution structure of the inner fluorescent glue after step 3) of the present invention is cured and baked;

Fig. 3 is a structural schematic diagram of the semi-finished white LED produced by the present invention after step 5);

Fig. 4 is a schematic structural diagram of a high-power white LED package of the present invention;

Fig. 5a is a front top view of the LED package emitting light as shown in Fig. 1;

Fig. 5b is a front top view of the LED package emitting light according to the present invention;

In Figure 1-4, 1-1, LED high-power bracket; 1, reflective bowl; 2, blue LED chip, 3, inner fluorescent glue; 4, outer fluorescent glue; 5, existing power type white light LED Encapsulated fluorescent glue structure; 6. The bottom surface of the exposed reflective bowl; 7. The radius of the bottom surface of the convex outer fluorescent glue; 8. The radius of the bottom surface of the inner fluorescent glue; 9. The upper edge of the reflective bowl; 10. Transparent silica gel; 11. Lens.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments, but is not limited thereto.

Embodiment 1,

As shown in FIG. 4 , a high-power white LED packaging structure includes a bottom-up LED high-power bracket 1-1, a reflective bowl cup 1, a blue LED chip 2, fluorescent glue, transparent silica gel 10 and a lens 11; The reflective bowl 1 is set on the LED high-power bracket 1-1, and the blue LED chip 2 is set in the reflective bowl 1 through conductive silver glue or high thermal conductivity insulating glue; the blue LED chip 2 passes through The gold wire is electrically connected to the LED high-power bracket 1-1; the blue LED chip 2 is coated with an inner layer of fluorescent glue 3 and an outer layer of fluorescent glue 4 from the inside out, and the particle size of the phosphor powder contained in the inner layer of fluorescent glue 3 is Smaller than the phosphor particle size contained in the outer layer of fluorescent glue 4; the coating range of the inner layer of fluorescent glue 3 is the entire blue LED chip 2 and the exposed reflective bowl bottom 6, and the inner layer of fluorescent light on the bottom of the reflective bowl The thickness of the glue 3 is smaller than the thickness of the blue LED chip 2; the outer fluorescent glue 4 completely covers the upper surface and the side wall of the blue LED chip 2, and is in the shape of a convex hull, and the outer fluorescent glue 4 of the convex hull shape The radius 7 of the bottom surface is smaller than the radius 8 of the bottom surface of the inner fluorescent glue; a lens 11 is arranged above the LED high-power bracket 1-1, and the lens 11 is filled with transparent silica gel 10. The size of the blue LED chip 2 is 24mil.

The fluorescent glue 3 in the inner layer is formed by mixing phosphor particles and transparent silica gel at a mass ratio of 1:6, and the particle size of the phosphor particles ranges from 7 to 13 μm. The outer fluorescent glue 4 is formed by mixing fluorescent powder particles and transparent silica gel at a mass ratio of 3:10, and the particle size range of the fluorescent powder particles is 20-23 μm. The refractive index of the transparent silica gel 10 is 1.5. The thickness of the inner fluorescent glue 3 is greater than 1/2 of the thickness of the blue LED chip 2 and smaller than the thickness of the blue LED chip 2, and the height of the upper surface of the convex outer fluorescent glue 4 is Lower than or equal to the upper edge 9 of the reflective bowl.

The lens 11 is a polycarbonate lens (PC lens).

Embodiment 2,

As shown in Figure 2-3. As described in Example 1, a method for preparing the above-mentioned high-power white LED packaging structure, the method steps are as follows:

1) Die bonding and wire bonding: Use conductive silver glue or high thermal conductivity insulating glue to fix the blue LED chip 2 in the reflective bowl 1, and cure and bake at 150°C-180°C for 60-90min, and then use gold wire to The blue LED chip 2 is welded on the LED high-power bracket 1-1;

2) Prepare the fluorescent glue 3 for the inner layer: mix and stir the fluorescent powder particles with a particle size of 7-13 μm and the transparent silica gel at a mass ratio of 1:6, and heat and defoam in a vacuum box to form the fluorescent glue 3 for the inner layer;

3) Coat the inner layer fluorescent glue 3 prepared in step 2) on the blue LED chip 2 by spin coating, and cure and bake at 150°C for 10-15 minutes; the appearance structure of the inner layer fluorescent glue 3 distribution after baking As shown in Figure 2; after step 3) curing and baking, the thickness of the inner fluorescent glue is greater than 1/2 of the thickness of the blue LED chip, and less than the thickness of the blue LED chip;

4) Prepare the outer layer fluorescent glue 4: mix and stir the phosphor particles with a particle size of 20-23 μm and the transparent silica gel at a mass ratio of 3:10, and heat and defoam in a vacuum box to form the outer layer fluorescent glue 4;

5) Spray the outer layer of fluorescent glue 4 prepared in step 4) on the upper surface of the inner layer of fluorescent glue 3 after curing and baking in step 3) by automatic dispensing, facing the blue LED chip 2, and immediately heat it at 150°C Bake for 5 minutes, then transfer to 120°C and bake for 30 minutes to form a convex hull shape enveloping the blue LED chip 2, that is, to make a semi-finished white LED; after baking in step 3), the outer fluorescent glue 4 and the cured inner The characteristics of infiltration between the fluorescent glue 3 are not easy to occur, and finally the distribution structure of the fluorescent glue is obtained, as shown in Figure 3; the upper surface height of the convex hull-shaped outer fluorescent glue described in step 5) is lower than or equal to the reflective bowl the upper edge of the cup;

6) For the semi-finished white LED produced in step 5), cover the lens 11, fill the transparent silica gel 10 in the lens 11, and bake it at 100°C for 1 hour to cure to obtain a high-power white LED.

Embodiment 3,

A high-power white LED package structure as described in Embodiment 1, the difference lies in that the size of the blue LED chip 2 is 50mil. The inner fluorescent glue 3 is formed by mixing fluorescent powder particles and transparent silica gel at a mass ratio of 1:5.

Embodiment 4,

As described in Example 3, a method for preparing the above-mentioned high-power white LED packaging structure, the method steps are as follows:

1) Die bonding and wire bonding: Use conductive silver glue or high thermal conductivity insulating glue to fix the blue LED chip 2 in the reflective bowl 1, and cure and bake at 150°C-180°C for 60-90min, and then use gold wire to The blue LED chip 2 is welded on the LED high-power bracket 1-1;

2) Preparation of fluorescent glue 3 for the inner layer: the fluorescent powder particles with a particle size of 7-13 μm and the transparent silica gel are mixed and stirred evenly at a mass ratio of 1:5, and heated and defoamed in a vacuum box to form the fluorescent glue for the inner layer;

3) Coat the inner layer fluorescent glue 3 prepared in step 2) on the blue LED chip 2 by spin coating, and cure and bake at 150°C for 10-15 minutes; the appearance structure of the inner layer fluorescent glue 3 distribution after baking As shown in Figure 2; after step 3) curing and baking, the thickness of the inner fluorescent glue is greater than 1/2 of the thickness of the blue LED chip, and less than the thickness of the blue LED chip;

4) Prepare the outer layer fluorescent glue 4: mix and stir the phosphor particles with a particle size of 20-23 μm and the transparent silica gel at a mass ratio of 3:10, and heat and defoam in a vacuum box to form the outer layer fluorescent glue 4;

5) Spray the outer layer of fluorescent glue 4 prepared in step 4) on the upper surface of the inner layer of fluorescent glue 3 after curing and baking in step 3) by automatic dispensing, facing the blue LED chip 2, and immediately heat it at 160°C. Bake for 6 minutes, then transfer to 120°C and bake for 35 minutes to form a convex hull shape enveloping the blue LED chip 2, that is, to make a semi-finished white LED; after baking in step 3), the outer fluorescent glue 4 and the cured inner layer The characteristics of infiltration between the fluorescent glue 3 are not easy to occur, and finally the distribution structure of the fluorescent glue is obtained, as shown in Figure 3; the upper surface height of the convex hull-shaped outer fluorescent glue described in step 5) is lower than or equal to the reflective bowl the upper edge of the cup;

6) For the semi-finished white light LED prepared in step 5), cover the lens 11, fill the transparent silica gel 10 in the lens 11, bake at 100° C. for 1.5 h to cure, and obtain a high-power white light LED.

Comparative example,

A high-power white LED package made by a conventional preparation process is shown in Figure 1: its structure is to prepare a single-layer fluorescent glue 5 on a blue LED chip, the size of the blue LED chip is 24mil, and the single-layer fluorescent The composition of the glue 5 is exactly the same as that of the inner layer fluorescent glue 3 described in Example 1. Fig. 5a is a front top view of the light-emitting LED package as shown in Fig. 1 .

As shown in FIG. 4 , the high-power white LED package structure is prepared by the method of the present invention, and the size of the blue LED chip is also 24mil. Fig. 5b is a front top view of the light-emitting LED package according to the present invention.

As shown in Figures 5a and 5b, compared with the LED packages prepared by the conventional manufacturing process, the spectral uniformity of the high-power white LED package of the present invention is greatly improved, the aperture is reduced, and the optical power of the blue LED chip is consistent with the final white light. The conversion efficiency of the outgoing luminous flux is increased by more than 5%.

Claims (9)

1. A packaging structure for high-power white light LEDs, comprising LED high-power brackets, reflective bowls, blue LED chips, fluorescent glue, transparent silica gel and lenses from bottom to top; it is characterized in that the reflective bowls are set On the LED high-power bracket, the blue LED chip is set in the reflective bowl through conductive silver glue or high thermal conductivity insulating glue; the blue LED chip is electrically connected to the LED high-power bracket through gold wire; The inner layer of fluorescent glue and the outer layer of fluorescent glue are coated from the inside to the outside, and the size of the phosphor particles contained in the inner layer of fluorescent glue is smaller than that of the phosphor particles contained in the outer layer of fluorescent glue; the coating of the inner layer of fluorescent glue The coverage area is the entire blue LED chip and the bottom surface of the exposed reflective bowl, the thickness of the inner layer of fluorescent glue on the bottom surface of the reflective bowl is smaller than the thickness of the blue LED chip; the outer layer of fluorescent glue completely covers the upper surface of the blue LED chip And the side wall is in the shape of a convex hull, the radius of the bottom surface of the convex hull-shaped outer layer of fluorescent glue is smaller than the radius of the bottom surface of the inner layer of fluorescent glue; a lens is arranged above the LED high-power bracket, and the lens is filled with transparent silica gel; The fluorescent glue in the inner layer is: fluorescent powder particles and transparent silica gel are mixed at a mass ratio of 1:7 to 1:5, and the particle size range of the phosphor powder particles is 7 to 13 μm; the fluorescent glue in the outer layer is: Phosphor powder particles and transparent silica gel are mixed at a mass ratio of 3:10, and the particle size range of phosphor powder particles is 20-23 μm. 2. A high-power white LED packaging structure as claimed in claim 1, characterized in that, the inner layer of fluorescent glue has a mass ratio of phosphor particles to transparent silica gel of 1:6. 3 . The high-power white LED packaging structure according to claim 1 , wherein the refractive index of the transparent silica gel is 1.5. 4 . 4. A packaging structure for high-power white LEDs according to claim 1, wherein the thickness of the inner fluorescent adhesive is greater than 1/2 of the thickness of the blue LED chip and less than that of the blue LED chip The height of the upper surface of the convex outer fluorescent glue is lower than or equal to the upper edge of the reflective bowl. 5. A high-power white LED packaging structure as claimed in claim 1, characterized in that, the size range of the blue LED chip is 24-50 mil; the lens is a PC lens. 6. the preparation method of a kind of high-power white light LED encapsulation structure as claimed in claim 1, is characterized in that, method step is as follows: 1) Solid crystal, wire bonding: Use conductive silver glue or high thermal conductivity insulating glue to fix the blue LED chip in the reflective bowl, and cure and bake at 150℃～180℃ for 60～90min, and then use gold wire to fix the blue LED chip. The chip is welded on the LED high-power bracket; 2) Prepare the fluorescent glue for the inner layer: mix and stir the fluorescent powder particles with a particle size of 7-13 μm and the transparent silica gel at a mass ratio of 1:5-1:7, and heat and defoam in a vacuum box to form the fluorescent glue for the inner layer ; 3) Coat the inner fluorescent glue prepared in step 2) on the blue LED chip by spin coating, and cure and bake at 150°C for 10-15 minutes; 4) Prepare the outer layer of fluorescent glue: mix and stir the phosphor particles with a particle size of 20-23 μm and transparent silica gel at a mass ratio of 3:10, and heat and defoam in a vacuum box to form the outer layer of fluorescent glue; 5) Spray the outer layer of fluorescent glue prepared in step 4) on the upper surface of the inner layer of fluorescent glue after curing and baking in step 3) by automatic dispensing, facing the blue LED chip, and immediately bake it at 140-160°C Bake for 3-7 minutes, then transfer to 110-130°C and bake for 20-40 minutes to form a convex hull shape enveloping the blue LED chip, that is, to produce a semi-finished white LED; 6) For the semi-finished white light LED prepared in step 5), cover the lens, fill the lens with transparent silica gel, bake at 90-110° C. for 1-1.5 h to cure, and obtain a high-power white light LED. 7 . The method according to claim 6 , wherein, in the step 2) when preparing the inner fluorescent glue: the phosphor particles and the transparent silica gel are mixed and stirred evenly at a mass ratio of 1:6. 8. The method according to claim 6, wherein the size range of the blue LED chip is 24-50 mil, and the refractive index of the transparent silica gel is 1.5; the lens is a PC lens. 9. The method according to claim 6, characterized in that, after step 3) curing and baking, the thickness of the inner fluorescent glue is greater than 1/2 of the thickness of the blue LED chip, and less than that of the blue LED chip. The thickness of the chip; Step 5) The height of the upper surface of the convex outer fluorescent glue is lower than or equal to the upper edge of the reflective bowl.