TWM612206U - A chip scale packaging light-emitting chip structure capable of decreasing temperature at light-out surface - Google Patents

Abstract

A chip scale packaging light-emitting chip structure capable of decreasing temperature at light-out surfaces is disclosed. The the chip scale packaging light-emitting chip structure capable of decreasing temperature at light-out surfaces is to form a light-emitting layer on surfaces of chips and substrate by powder coating. The light-emitting layer is composed of fluorescent powder or powders capable of emitting light; coat a transparent layer with thickness less than 0.01 mm on the light-emitting layer surfaces. The transparent layer is composed of transparent glues or resins, and cover a layer not generating heat on the transparent layer surface to form the chip scale packaging light-emitting chip structure capable of decreasing temperature at light-out surfaces.

Description

Light-emitting chip structure of chip-level package capable of reducing light-emitting surface temperature

The present invention provides a light-emitting chip structure of a wafer-level package that can reduce the temperature of the light-emitting surface, thereby improving its safety and reliability of luminous efficacy, and achieving the purpose of prolonging the life of the light-emitting chip.

The current LED manufacturing and packaging process is a one-time packaging process. Although a settling agent is used in the manufacturing process, the phosphor suspended in the phosphor used for one-time packaging cannot be completely settled on the substrate and chip. When the excitation light is bright, the phosphor that is still suspended in the phosphor without sedimentation during a packaging process will regenerate heat energy due to the excitation light, and the heat energy will accumulate in the phosphor layer on the light-emitting surface and cannot be used by the thermal conductive plate. Or the substrate effectively dissipates heat, so the light-emitting diode made by the conventional process generally has the shortcomings of light-emitting structure defects and excessively high light-emitting surface temperature. The above-mentioned shortcomings seriously affect the safety, luminous efficacy and lifespan of LEDs currently on the market, and cannot meet the needs of the lighting industry and the market in the future.

In summary, the development of a light-emitting chip structure that can reduce the temperature of the light-emitting surface, thereby improving its use safety and light-emitting efficiency, is an important issue to be solved and developed urgently.

In view of the above technical background, in order to meet the requirements of the industry, the first object of the present invention is to provide a light emitting chip structure of a wafer level package that can reduce the temperature of the light emitting surface. Innovatively, the light-emitting chip structure of the new type of wafer-level package that can reduce the temperature of the light-emitting surface is to coat a light-emitting powder layer on the surface of the wafer and the substrate by a powder coating technology, and the light-emitting powder layer is made of phosphor or arbitrary A light-excitable powder is formed; a transparent glue layer with a thickness of less than 0.01mm is cured on the surface of the luminescent powder layer, so that the luminescent powder layer is completely attached to the surface of the wafer and the substrate, thereby completing the first One-time encapsulation, the transparent glue layer is composed of transparent glue or resin that does not contain luminescent powder, and a coating that does not generate heat is encapsulated on the surface of the transparent glue layer with a thickness of less than 0.01mm. The packaging process constitutes the light-emitting chip structure of the wafer-level packaging that can reduce the temperature of the light-emitting surface.

Specifically, the phosphor or any light-excitable powder converts the heat generated by light to conduct heat through the phosphor or any light-excitable powder only on the surface of the chip and the substrate, by this way Quickly conduct heat to the substrate to dissipate heat, and achieve the heat dissipation effect of the light-emitting chip structure of the wafer-level package that can reduce the temperature of the light-emitting surface.

In a specific embodiment, the light-emitting chip structure of the wafer-level package that can reduce the temperature of the light-emitting surface uses powder coating related technology to make the light-emitting powder or phosphor first uniformly adsorb or deposit on the chip and the substrate or the circuit board. After the luminescent powder or phosphor forms the luminescent powder layer on the wafer and the substrate or circuit board, then use transparent glue or resin without luminescent powder to cure on the surface of the luminescent powder layer to a thickness of less than 0.01mm The transparent glue layer makes the phosphor in the luminescent powder layer completely adhere to the crystal On the surface of the sheet and the substrate, the first encapsulation is thereby completed, and then a coating that does not generate heat is encapsulated on the surface of the transparent adhesive layer with a thickness of less than 0.01mm, whereby the secondary encapsulation process constitutes the above-mentioned reduction The light-emitting chip structure of the chip-level package with the temperature of the light-emitting surface.

In a preferred embodiment, the light-emitting surface of the light-emitting chip structure of the above-mentioned wafer-level package capable of reducing the temperature of the light-emitting surface is five sides.

In one embodiment, the material of the above-mentioned transparent glue without luminescent powder is silicon glue, epoxy resin, polyurethane, acrylic resin or any combination thereof.

In a specific embodiment, the thickness of the above-mentioned luminescent powder layer is less than 1 mm.

In a specific embodiment, the thickness of the above-mentioned transparent adhesive layer is less than 0.01 mm.

In one embodiment, the electron microscope image of the internal structure in which the above-mentioned luminescent powder layer is completely attached to the surface of the wafer and the substrate is shown in FIG. 2 or FIG. 3.

Accordingly, it is proved that the phosphor of the present invention is closely and uniformly attached to the substrate and the chip completely.

The inventor emphasizes that the structure of the non-heat-generating coating of the present invention does not contain any luminescent powder, so the function of the non-heat-generating coating is only to guide light and atomize and mix light. Coating structure that generates heat energy from light. Preferably, the non-heat-generating coating is an optical diffusion coating.

In contrast, the current light-emitting diodes use a fluorescent glue or light-emitting film mixed with phosphor powder to perform a packaging process, and the fluorescent glue layer or light-emitting film layer is combined The structure will also contain suspended phosphors. When the suspended phosphors are excited to emit light, they also generate heat. However, the phosphor layer or the light-emitting film layer has poor heat dissipation effect and the phosphors are suspended in the gel. As a result, the uniformity of the internal structure of the adhesive layer is not good, so the heat generated in the adhesive layer cannot be conducted and effectively dissipated; in other words, after the current LED phosphor and glue are mixed for one package, the phosphor has not completely settled, causing some It is still suspended in the glue, so that the heat generated by the phosphor that has not settled in the colloid can not be dissipated in the colloid, making the light-emitting surface temperature of the traditional one-time packaged light-emitting diode too high, greatly reducing its safety and lifespan.

Accordingly, the light-emitting chip structure of the wafer-level package provided by the present invention that can reduce the temperature of the light-emitting surface is to first make the light-emitting powder or phosphor completely adhere to the chip and the substrate through the secondary packaging process, and the light-emitting powder layer is The heat generated by the conversion of the phosphor into the light is transferred by the phosphor only on the surface of the chip and the substrate, and this way is quickly transferred to the substrate to dissipate heat, so it can effectively reduce the light output of the light-emitting diode provided by the present invention. The surface temperature can achieve the purpose of improving the safety of the luminous products and prolonging the service life.

The second object of the present invention is to provide a method for preparing a light emitting chip structure of a wafer level package that can reduce the temperature of the light emitting surface. It includes the following steps.

Step 1: Coat any powder that can excite light on the surface of the wafer and the substrate by powder coating technology to form a luminescent powder layer.

Step 2: curing a transparent adhesive layer with a thickness of less than 0.01mm on the surface of the above-mentioned luminescent powder layer, so that the luminescent powder layer is completely attached to the surface of the chip and the substrate, thereby completing the first packaging. The transparent glue layer less than 0.01mm is It is made of transparent glue or resin without luminous powder.

Step 3: On the surface of the transparent glue layer, a coating that does not generate heat is encapsulated, and the light-emitting chip structure of the wafer-level package that can reduce the temperature of the light-emitting surface is fabricated by a secondary packaging process.

Specifically, the heat generated by the light-excitable powder converted to light is conducted through only the light-excitable powder on the surface of the wafer and the substrate, and the heat is quickly transferred to the substrate to dissipate heat through this way, so as to achieve the above-mentioned heat dissipation. The heat dissipation effect of the light emitting chip structure of the wafer level package that reduces the temperature of the light emitting surface.

In a preferred embodiment, the light-emitting surface of the light-emitting chip structure of the above-mentioned wafer-level package is five-sided.

In one embodiment, any of the above-mentioned light-excitable powder includes phosphor powder or surface-treated phosphor composite powder. Preferably, the particle size of any light-excitable powder is 0.1-100 microns.

In a specific embodiment, the thickness of the above-mentioned luminescent powder layer is less than 1 mm.

In one embodiment, the material of the above-mentioned transparent glue without luminescent powder is silicon glue, epoxy resin, polyurethane, acrylic resin or any combination thereof.

In one embodiment, the method of curing the transparent adhesive layer with a thickness of less than 0.01 mm in the above step 2 includes heat curing, ultraviolet curing, or a combination thereof.

In one embodiment, the non-heat-generating coating described in step 3 above is an optical diffusion coating.

The key to the above-mentioned preparation method is on the chip or circuit board Use powder coating technology to first coat the luminescent powder layer, and then use transparent glue without luminescent powder to cure on the surface of the luminescent powder layer to form a transparent glue layer with a thickness of less than 0.01mm, complete the first encapsulation, and then The surface of the transparent adhesive layer with a thickness of less than 0.01 mm is further encapsulated with a coating that does not generate heat, so that the secondary encapsulation process constitutes the above-mentioned light emitting chip structure of the wafer level package that can reduce the temperature of the light emitting surface. This preparation method is a secondary packaging process to sequentially manufacture the functional structure layers of the light-emitting chip, so the uniformity of the functional structure layers is good, especially the transparent adhesive layer does not contain luminescent powder, so there will be no heat generated by light excitation The shortcomings or the uneven dispersion of the internal structure of the defect. The inventor emphasizes that the phosphor in the light-emitting chip structure of the wafer-level package provided by the present invention can reduce the light-emitting surface temperature to convert the heat generated by the light, and the heat is transferred by the phosphor only on the surface of the chip and the substrate. Heat conduction to the substrate to dissipate heat, so it can effectively reduce the temperature of the light-emitting surface, and achieve the purpose of improving the safety of the light-emitting product and extending the service life. Compared with the conventional light-emitting diodes made by using one-dose fluorescent glue mixed with phosphors and one-time packaging process, the light-emitting chip of the chip-level package provided by the present invention effectively reduces the temperature of the light-emitting surface, so the present invention The wafer-level packaged light-emitting chip manufactured by the preparation method of the invention has good safety in use, high light-emitting efficiency and long service life, which is significantly better than conventional light-emitting products.

The third object of the present invention is to provide a method for reducing the temperature of the light-emitting surface of a light-emitting chip, which includes curing the light-emitting surface with transparent glue without luminescent powder during the manufacturing process of the light-emitting chip to form a transparent layer with a thickness of less than 0.01 mm. Adhesive layer, so that the phosphor in the phosphor layer of the light-emitting chip is completely attached to the substrate of the light-emitting chip and the surface of the chip, thereby enabling the phosphor to conduct heat to the substrate to achieve The purpose of reducing the temperature of the light-emitting surface of the light-emitting chip.

In a preferred embodiment, the light-emitting surface of the above-mentioned light-emitting chip is five-sided.

In one embodiment, the material of the above-mentioned transparent glue without luminescent powder is silicon glue, epoxy resin, polyurethane, acrylic resin or any combination thereof.

In one embodiment, the thickness of the above-mentioned transparent adhesive layer is less than 0.01 mm.

In summary, the light-emitting chip structure of the wafer-level package of the present invention that can reduce the temperature of the light-emitting surface has at least the following unpredictable effects and advantages: (1) The present invention is to use a secondary packaging process to manufacture light-emitting chips, which provides one The transparent glue layer with a thickness of less than 0.01mm that makes the phosphor completely adhere to the surface of the substrate and the chip and does not generate heat. At the same time, the new type provides the phosphor in the light-emitting chip structure of the chip-level package that can reduce the temperature of the light-emitting surface The heat generated by the powder converted to light, through only the heat conduction of the phosphor on the surface of the wafer and the substrate, and the heat conduction to the substrate quickly through this way, so it can effectively reduce the temperature of the light emitting surface, and improve the safety and extension of the use of light-emitting products. The purpose of service life; (2) The luminescent powder layer of the present invention is completely coated on the surface of the chip and the substrate, so it can effectively improve the luminous efficiency of the luminescent powder layer. Therefore, the new type has high economic benefits and is compared with conventional ones. The known light-emitting chip or light-emitting diode reduces the amount of light-emitting powder by at least 15%; and (3) provides a method for reducing the temperature of the light-emitting surface and prolonging the service life of the light-emitting device; The phosphor in the luminescent powder layer is completely attached to the substrate and the surface of the chip with a transparent adhesive layer with a thickness of less than 0.01mm. The secondary packaging technology of the luminescent chip reduces the temperature of the light-emitting surface, reduces the thermal damage of the luminescent product, and extends the service life. the goal of.

1: The light-emitting chip structure of the chip-level package that can reduce the temperature of the light-emitting surface

11: substrate

12: chip

13: Luminous powder layer

14: Transparent glue layer with thickness less than 0.01mm

15: Coating that does not generate heat

[Fig. 1] is a schematic diagram of the structure of the light-emitting chip of the wafer-level package that can reduce the temperature of the light-emitting surface of the present invention.

[Figure 2] is one of the electron microscope images of the light-emitting powder layer of the light-emitting chip of the wafer-level package and the internal structure of the substrate and the chip that can reduce the temperature of the light-emitting surface of the present invention.

[Figure 3] is the second electron microscope image of the luminescent powder layer of the luminescent chip of the wafer-level package and the internal structure of the substrate and the chip that can reduce the temperature of the light-emitting surface of the present invention.

The foregoing and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of a preferred embodiment with reference to the drawings. In order to thoroughly understand the present invention, detailed steps and their composition will be presented in the following description. Obviously, the implementation of the present invention is not limited to the special details familiar to those skilled in the field. On the other hand, well-known components or steps are not described in details to avoid unnecessary limitation of the present invention. The preferred embodiments of the present invention will be described in detail as follows. However, in addition to these detailed descriptions, the present invention can also be widely implemented in other embodiments, and the scope of the present invention is not limited, which shall be subject to the following patent scope .

One embodiment of the present invention provides a light-emitting chip structure of a wafer-level package capable of reducing the temperature of the light-emitting surface and a preparation method thereof. It includes the following steps.

Step 1: Apply any powder that can excite light with powder coating technology A luminous powder layer is formed on the surface of the chip and the substrate.

Step 2: curing a transparent adhesive layer with a thickness of less than 0.01mm on the surface of the above-mentioned luminescent powder layer, so that the luminescent powder layer is completely attached to the surface of the chip and the substrate, thereby completing the first packaging. The glue layer is composed of transparent glue or resin without luminescent powder.

Step 3: On the front or five sides of the transparent adhesive layer with a thickness of less than 0.01mm, a coating that does not generate heat is encapsulated, and the light emission of the chip-level package that can reduce the temperature of the light-emitting surface is formed by the secondary packaging process Wafer structure.

Specifically, the heat generated by the light-excitable powder converted to light is conducted through only the light-excitable powder on the surface of the wafer and the substrate, and the heat is quickly transferred to the substrate to dissipate heat through this way, so as to achieve the above-mentioned heat dissipation. The heat dissipation effect of the light emitting chip structure of the wafer level package that reduces the temperature of the light emitting surface.

In a preferred embodiment, the light-emitting surface of the light-emitting chip structure of the above-mentioned wafer-level package capable of reducing the temperature of the light-emitting surface is five sides.

In one embodiment, any of the above-mentioned light-excitable powder includes phosphor powder or surface-treated phosphor composite powder. Preferably, the particle size of any light-excitable powder is 0.1-100 microns.

In a specific embodiment, the thickness of the above-mentioned luminescent powder layer is less than 1 mm.

In one embodiment, the electron microscope image of the internal structure in which the above-mentioned luminescent powder layer is completely attached to the surface of the wafer and the substrate is shown in FIG. 2 or FIG. 3. According to this, it is proved that the phosphor of the present invention is closely consistent and completely attached to the substrate and the chip. on.

In one embodiment, the material of the above-mentioned transparent glue or resin without luminescent powder is silicon glue, epoxy resin, polyurethane, acrylic resin or any combination thereof.

In one embodiment, the method of curing a transparent adhesive layer with a thickness of less than 0.01 mm in the above step 2 includes heat curing, ultraviolet curing, or a combination thereof.

In one embodiment, the non-heat-generating coating described in step 3 above is an optical diffusion coating.

The key to the above-mentioned light-emitting chip structure and preparation method of the wafer-level package that can reduce the temperature of the light-emitting surface is to first coat the light-emitting powder layer on the chip or substrate, and then use transparent glue without light-emitting powder on the light-emitting powder The surface of the layer is cured to form a transparent adhesive layer with a thickness of less than 0.01mm, and the first encapsulation is completed, and then a coating that does not generate heat is encapsulated on the front or five sides of the transparent adhesive layer with a thickness of less than 0.01mm. The sub-package process constitutes the above-mentioned light emitting chip structure of the wafer level package which can reduce the temperature of the light emitting surface.

The second embodiment of the present invention provides a method for lowering the temperature of the light-emitting surface of a light-emitting chip, which includes curing the surface of the light-emitting powder layer with transparent glue without light-emitting powder during the manufacturing process of the light-emitting chip to form a thickness less than The transparent glue layer of 0.01mm is used to make the phosphor in the luminescent powder layer completely adhere to the substrate and the surface of the light-emitting chip, thereby allowing the phosphor to conduct heat to the substrate, so as to reduce the light-emitting chip The purpose of the temperature of the light emitting surface.

In a preferred embodiment, the light-emitting surface of the above-mentioned light-emitting chip is five-sided.

In one embodiment, the above-mentioned transparent glue material without luminescent powder It is silicone, epoxy, polyurethane, acrylic resin or any combination thereof.

In one embodiment, the thickness of the above-mentioned transparent adhesive layer is less than 0.01 mm.

In summary, the light-emitting chip structure of the wafer-level package of the new type that can reduce the temperature of the light-emitting surface has at least the following unpredictable effects and advantages: (1) The new type is to manufacture the light-emitting chip using a secondary packaging process, which provides one The transparent glue layer with a thickness of less than 0.01mm that makes the phosphor completely adhere to the surface of the substrate and the chip and does not generate heat. At the same time, the new type provides the phosphor in the light-emitting chip structure of the chip-level package that can reduce the temperature of the light-emitting surface The heat generated by the powder converted to light, through only the heat conduction of the phosphor on the surface of the wafer and the substrate, and the heat conduction to the substrate quickly through this way, so it can effectively reduce the temperature of the light emitting surface, and improve the safety and extension of the use of light-emitting products. The purpose of service life; (2) The luminescent powder layer of the present invention is completely coated on the surface of the chip and the substrate, so it can effectively improve the luminous efficiency of the luminescent powder layer. Therefore, the new type has high economic benefits and is compared with conventional ones. The known light-emitting chip or light-emitting diode reduces the amount of light-emitting powder by at least 15%; and (3) provides a method for reducing the temperature of the light-emitting surface and prolonging the service life of the light-emitting device; The phosphor in the luminescent powder layer is completely attached to the substrate and the surface of the chip with a transparent adhesive layer with a thickness of less than 0.01mm. The secondary packaging technology of the luminescent chip reduces the temperature of the light-emitting surface, reduces the thermal damage of the luminescent product, and extends the service life. the goal of

According to a representative embodiment of the present invention, the present invention provides a light emitting chip structure 1 of a wafer level package capable of reducing the temperature of the light emitting surface as shown in Figure 1. The process steps are: placing a chip 12 on a substrate 11 , and placing a chip 12 on the substrate 11 and the chip The surface of 12 is coated with luminescent powder by powder coating technology to form a luminescent powder layer 13 , and then a transparent glue without luminescent powder is coated or glued on the surface of the luminescent powder layer 13. The transparent glue without luminescent powder is passed through firmware 14 is formed of transparent plastic layer thickness of less than 0.01mm on a surface of the luminescent powder layer 13, whereby the light emitting layer emits light pink powder in 13 smoothly placed on the surface of the wafer 12 and the substrate 11, the first complete Package, and then package a non-heat-generating coating 15 on the front surface of the transparent adhesive layer 14 with a thickness of less than 0.01mm, and the light-emitting chip of the wafer-level package that can reduce the temperature of the light-emitting surface is produced by the secondary packaging process Structure 1 .

The luminescent powder layer 13 of the above representative embodiment is completely attached to the surface of the wafer 12 and the substrate 11 , and the electron microscope cross-sectional image diagram of the internal structure is shown in FIG. 2 or FIG. 3. According to this, it is proved that the phosphor of the present invention is closely and uniformly attached to the substrate and the chip.

In an experimental example, according to the steps described in the above representative embodiment, 0.5 g of luminescent powder is used to make the light-emitting chip (NCC-COB13.5) of the present invention that can reduce the temperature of the light-emitting surface. The light-emitting chip (No. TOYONIA) sold once in the packaging process was used as the experimental control group. The experiment was performed with 22 watts and 50 watts respectively, and the temperature of the substrate and the light-emitting surface was measured at the same time. The results are shown in Table 1. Compared with the light-emitting chip of the one-time packaging process, the light-emitting chip of the wafer-level package that can reduce the temperature of the light-emitting surface of the present invention can greatly reduce the temperature of the light-emitting surface to at least 50°C. Accordingly, compared with the conventional one-time packaging process technology, the present invention does have unpredictable technical effects.

In summary, the light-emitting chip structure of the wafer-level package of the new type that can reduce the temperature of the light-emitting surface has at least the following unpredictable effects and advantages: (1) The present invention provides a thickness that has good structural uniformity and does not generate heat. The transparent adhesive layer is smaller than 0.01mm. At the same time, the phosphor in the light-emitting chip structure of the wafer-level package provided by the present invention can reduce the light-emitting surface temperature to convert the heat generated by the light, through only the phosphor on the surface of the chip and the substrate By this way, heat conduction to the substrate quickly to dissipate heat, so it can effectively reduce the temperature of the light-emitting surface, and achieve the purpose of improving the safety of light-emitting products and prolonging the service life; (2) The new type of light-emitting powder layer is completely covered Covered on a chip or substrate, it can effectively improve the luminous efficiency of the luminescent powder layer, so the present invention has high economic benefits and reduces the amount of luminescent powder by at least 15% compared with conventional light-emitting chips or light-emitting diodes; and ( 3) Provide a method to reduce the temperature of the light-emitting surface and prolong the service life of the light-emitting device; reduce the temperature of the light-emitting surface by sequentially introducing a light-emitting powder layer and a transparent adhesive layer with a thickness of less than 0.01mm to reduce the temperature of the light-emitting surface and reduce the cost of the light-emitting product. Heat damage to achieve the purpose of extending the service life.

Although specific experimental examples are used to illustrate the present invention, the scope of the present invention is not limited. As long as the spirit of the present invention is not deviated, those skilled in the art understand that various modifications or changes can be made without departing from the intention and scope of the present invention. In addition, the abstract part and title are only used to assist in searching for patent documents, not to limit the text. The scope of new rights.

1: The light-emitting chip structure of the chip-level package that can reduce the temperature of the light-emitting surface

11: substrate

12: chip

13: Luminous powder layer

14: Transparent glue layer with thickness less than 0.01mm

15: Coating that does not generate heat

Claims (5)

A wafer-level packaged light-emitting chip structure that can reduce the temperature of the light-emitting surface. Its constituent elements include a wafer, a substrate, a luminescent powder layer, a transparent adhesive layer and a coating that does not generate heat; the surface of the wafer and the substrate is coated with powder The luminescent powder layer is covered by cloth technology, and the luminescent powder layer is composed of phosphor or any powder that can excite light; on the surface of the luminescent powder layer, a transparent adhesive layer with a thickness of less than 0.01mm is cured to make The luminescent powder layer is completely attached to the surface of the wafer and the substrate, the transparent glue layer is composed of transparent glue or resin that does not contain luminescent powder, and the transparent glue layer with a thickness of less than 0.01mm is encapsulated on the surface of the transparent glue layer. The heat-generating coating constitutes the light-emitting chip structure of the wafer-level package that can reduce the temperature of the light-emitting surface. The light-emitting chip structure of the wafer-level package capable of lowering the temperature of the light-emitting surface of claim 1, wherein the light-emitting chip structure of the above-mentioned wafer-level package capable of lowering the temperature of the light-emitting surface has five light-emitting surfaces. For example, the light-emitting chip structure of a wafer-level package capable of reducing the temperature of the light-emitting surface of claim 1, wherein any of the above-mentioned light-excitable powders includes phosphors or surface-treated phosphor composite powders, which can be excited The particle size of the light powder is 0.1-100 microns. For example, the light-emitting chip structure of the chip-level package that can reduce the temperature of the light-emitting surface in claim 1, wherein the material of the transparent glue or resin that does not contain light-emitting powder is silicon, epoxy, polyurethane, acrylic resin or any of them combination. The light-emitting chip structure of a wafer-level package capable of reducing the temperature of the light-emitting surface as in claim 1, wherein the thickness of the above-mentioned light-emitting powder layer is less than 1 mm.

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