KR101490862B1 - LED package and method of manufacturing the LED package - Google Patents

Abstract

A web filter capable of providing a uniform color coordinate and removing a yellow ring, an LED package using the same, and a manufacturing method of the LED package. The proposed web filter is produced by electrospinning a plurality of fibers in a sparse form, and a mixed solution containing a polymer, a fluorescent material and a solvent is used as a raw material. The proposed LED package includes a light emitting element, a substrate having a cavity in which a light emitting element is mounted, a mixed solution including a polymer, a fluorescent material, and a solvent, which are disposed on the upper portion of the light emitting element so as to be spaced apart from the light emitting element, And a transparent resin layer formed between the light emitting element and the web filter.

Description

[0001] The present invention relates to an LED package and a manufacturing method of the LED package,

The present invention relates to an LED package and a method of manufacturing the LED package, and more particularly, to an LED package manufactured by electrospinning a raw material including a phosphor and a method of manufacturing the LED package.

Generally, as a method for implementing a white LED employed in a lighting apparatus or the like, a method of combining a blue LED chip and a YAG phosphor (for example, yellow phosphor) having a wavelength of approximately 430 nm to 470 nm in a visible light region, A combination of a red / green / blue phosphor, and a combination of a red / green / blue LED chip. The first method is mainly used because the white LED can be implemented at a low cost and the light efficiency is high.

When a white LED is realized by combining a blue LED chip and a YAG-based phosphor (for example, yellow phosphor), a structure as illustrated in FIG. 1 is obtained.

The LED package of Fig. 1 includes an LED chip 14; A first substrate 10 on which the LED chip 14 is mounted; A second substrate 20 disposed on the first substrate 10 and having a cavity formed in a region corresponding to a region where the LED chip 14 is mounted; Pattern electrodes 12a and 12b formed on the first substrate 10 in a predetermined shape and connected to the LED chip 14 via a wire 16; And a phosphor layer 18 filled to cover the LED chip 14 after the phosphor (for example, yellow phosphor) and silicon (or epoxy) are blended according to a predetermined blending ratio. The first substrate 10 may be referred to as a lower substrate and the second substrate 20 may be referred to as an upper substrate.

In order to form the phosphor layer 18 in such an LED package, various methods are adopted for each manufacturer.

A method widely used is a method in which a predetermined amount of fluorescent material is applied to the periphery of the LED chip 14 by using a syringe (not shown). The LED package using this method is called a dispensing type LED package.

It is most preferable that the upper surface of the phosphor layer 18 to be filled in the cavity formed in the substrate 30 is kept horizontal as in the conventional dispensing type LED package as shown in FIG. However, it is difficult to mold the phosphor layer 18 horizontally due to the change in the amount of the phosphors doped with a syringe (not shown) and the liquid tension. As the amount of the phosphor to be dotted is increased or decreased, the upper surface of the phosphor layer 18 becomes concave or convex as shown in Fig. 2 (c), as shown in Fig. 2 (a). As a result, the distribution of color coordinates of dispensing type LED packages is wide. This means that a large number of unconventional products are continuously generated.

In other words, a conventional dispensing-type LED package inserts a phosphor and silicon (or epoxy) in a syringe (not shown) and discharges the light by a predetermined amount. However, the phosphor injected into a syringe (not shown) is precipitated downward over time (for example, about 3 hours to 4 hours). As a result, a change in the amount of silicon (or epoxy) to be mixed occurs even though silicon (or epoxy) has to be mixed evenly. That is, since the phosphor particles sink in the syringe (not shown) as time elapses, adversely affecting the product characteristic value. Even if the same syringe is used to discharge a predetermined amount, there is a deviation between the color coordinates of the LED packages using the same syringe. An LED package with a large deviation of color coordinates from other LED packages is classified as unconventional, and such a large number of unconventional products are continuously generated. (See FIG. 3B) based on the chromaticity coordinate data (chrom x, chrom y) on the data sheet of FIG. In accordance with the minute change amount of the phosphor discharged from a syringe (not shown), products such as those shown in Figs. 2 (a) and 2 (c) are inevitably produced and processed as irregular products.

Therefore, conventionally, in the case of manufacturing a dispensing type LED package, it is necessary to maintain the uniformity of the phosphor particles injected into a syringe (not shown) to reduce unconventional products (defective products), to control the amount of viscosity of the base material and the set material, Control of the volume with changes in head pressure, and volume control with changes in the working environment.

However, despite the careful attention to detail, it is difficult to reduce the incidence of products treated as uncoated because of the wide spread of color coordinates described above.

Particularly, when the thickness of the phosphor layer 18 surrounding the LED chip 14 becomes uneven, a change occurs in the path through which the light generated from the LED chip 14 passes through the phosphor layer 18. This typically results in a yellow ring along the edge of the illuminated light when illuminating the subject. The yellow ring not only does not give a good feel to the exterior, but it is also a major cause of poor picture quality when taking pictures in normal camera flash.

It is an object of the present invention to provide an LED package and a method of fabricating the LED package that can provide a uniform color coordinate and remove a yellow ring.

In order to accomplish the above object, a web filter according to a preferred embodiment of the present invention comprises a mixed solution including a polymer, a phosphor, and a solvent, wherein a plurality of fibers are formed into a spongy shape by electrospinning.

A phosphor is contained in each of the plurality of fibers.

The polymer is one of TPU (Thermal Polyurethane), PC (Polycarbonate), and PMMA (Polymethyl methacrylate).

The mixed solution is prepared by adjusting the polymer to 10 to 40 wt% and the phosphor to 50 to 300 wt% based on the polymer.

Each of the plurality of fibers has a diameter of 500 nm to 20 탆.

An LED package according to an embodiment of the present invention includes: a light emitting element; A substrate having a cavity in which a light emitting element is mounted; A web filter provided on an upper portion of the light emitting device so as to be spaced apart from the light emitting device in the cavity, wherein a plurality of fibers are formed into a spongy shape by electrospinning using a mixed solution containing a polymer, a fluorescent material and a solvent as a raw material; And a transparent resin layer formed between the light emitting element and the web filter.

A transparent resin layer using silicon and / or a diffuser is additionally formed on the top of the web filter.

The web filter contains a phosphor in each of a plurality of fibers.

The polymer is one of TPU (Thermal Polyurethane), PC (Polycarbonate), and PMMA (Polymethyl methacrylate).

The mixed solution is prepared by adjusting the polymer to 10 to 40 wt% and the phosphor to 50 to 300 wt% based on the polymer.

Each of the plurality of fibers has a diameter of 500 nm to 20 탆, and the web filter has a thickness of 10 to 200 탆.

And a white reflective layer formed on the cavity so as to cover the inner wall and the bottom surface of the cavity, the reflective layer being formed on a portion of the cavity excluding the region where the light emitting device is mounted.

The reflective layer is rounded inward.

The reflective layer includes at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene).

The reflective layer contains at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene) as a main material, and the main material is added in an amount of 5 to 60 wt%.

The reflective layer is made of a base material having a silicone resin content of 5 to 30 wt% and an epoxy resin content of 20 to 65 wt% together with the main material.

And may further include a white reflective layer formed on the cavity so as to cover the bottom surface of the cavity except a region where the light emitting device is mounted.

A method of fabricating an LED package according to an embodiment of the present invention includes: preparing a web filter having a plurality of fibers formed into a spongy shape by electrospinning using a mixed solution containing a polymer, a phosphor, and a solvent as raw materials; A light emitting element mounting step of mounting the light emitting element on the bottom surface of the cavity of the substrate; A transparent resin layer forming step of filling a cavity in which the light emitting element is mounted with a transparent resin to form a transparent resin layer; And a web filter attaching step of attaching the web filter to the upper surface of the transparent resin layer.

The transparent resin layer forming step includes a transparent resin primary filling step of filling the upper surface of the transparent resin filled in the cavity in which the light emitting element is mounted with the recessed surface and filling the light emitting element with embedding; A transparent resin heat treatment step of performing heat treatment so that the filled transparent resin is in a gel state; And a transparent resin secondary charging step for recharging a transparent resin on the upper surface of the recessed transparent resin.

And forming a transparent resin layer using silicon and / or a diffuser on top of the web filter.

The web filter contains a phosphor in each of a plurality of fibers.

The polymer is one of TPU (Thermal Polyurethane), PC (Polycarbonate), and PMMA (Polymethyl methacrylate).

The mixed solution is prepared by adjusting the polymer to 10 to 40 wt% and the phosphor to 50 to 300 wt% based on the polymer.

Each of the plurality of fibers has a diameter of 500 nm to 20 탆, and the web filter has a thickness of 10 to 200 탆.

Forming a white reflective layer on the cavity so as to cover the inner wall and the bottom of the cavity, and forming a reflective layer of white on the portion excluding the region where the light emitting device is mounted.

The reflective layer is rounded inward.

The reflective layer includes at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene).

The reflective layer contains at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene) as a main material, and the main material is added in an amount of 5 to 60 wt%.

The reflective layer is made of a base material having a silicone resin content of 5 to 30 wt% and an epoxy resin content of 20 to 65 wt% together with the main material.

And a reflective layer forming step of forming a white reflective layer on the cavity so as to cover the bottom surface of the cavity and forming a white reflective layer on a portion excluding the area where the light emitting device is mounted.

According to the present invention having such a configuration, the following effects can be obtained.

The web filter has a uniform thickness and the phosphor ratio is constant per unit area as compared with the conventional dispensing type, so that a desired color coordinate can be easily obtained. This improves the stability of the color coordinate, thereby eliminating the required color coordinate rank out. That is, by appropriately combining the phosphors, it is possible to provide any LED package having a color coordinate corresponding to the color coordinate required region of the purchaser. Therefore, an LED package employing such a web filter can reduce the defect rate as compared with the prior art, thereby improving the production yield.

The light emitting element and the web filter are spaced apart from each other, thereby suppressing deterioration of the phosphor. In terms of long-term reliability, it provides effects such as providing uniform color coordinates, eliminating the yellow ring and reducing the amount of light very little, or providing long-term white light.

The web filter, like a nonwoven fabric, has a plurality of fibers in a sparse form and the silicon penetrates into the voids between the fibers and the fibers, thereby increasing the refractive index and transmittance. Accordingly, the amount of light is amplified by the phosphor particles contained in each fiber of the LED package in which the web filter 52 is employed, so that the amount of light is not lowered as compared with the conventional dispensing type LED package.

In the LED package of the embodiment of the present invention, the phosphor ratio of the web filter is constant per unit area, so that not only the desired color coordinates but also the effect of removing the yellow ring is obtained incidentally.

The LED package according to the embodiment of the present invention is provided with a web filter made of a material having a high transmittance so as to be spaced apart from the light emitting device to suppress deterioration of the phosphor due to heat generated in the light emitting device, Thereby eliminating yellow ring generation. Therefore, the LED package according to the embodiment of the present invention is more reliable than the conventional LED package in terms of long-term reliability.

Hereinafter, a web filter according to an embodiment of the present invention, an LED package using the web filter, and a method of manufacturing the LED package will be described with reference to the accompanying drawings. The LED package of the present invention is applicable to all SMD type packages such as a ceramic package, a plastic package, a lead frame type package, and a plastic + lead frame type package.

(Embodiment 1)

FIGS. 4 to 10 are views for explaining the configuration and manufacturing process of the LED package according to the first embodiment of the present invention. 11 is a photograph of the web filter of the first embodiment of the present invention. 12 is an enlarged photograph of a part of the web filter of Fig.

4, a light emitting device 44 (LED chip) is mounted on the bottom surface of the cavity 42, and a wire 46 is bonded to the cavity 42, as shown in FIG. 4, after the substrate 40 on which the stepped cavity 42 is formed is prepared. do. The stepped stepping of the cavity 42 facilitates the subsequent installation of the web filter 52 and allows the diffusion layer 54 to be easily formed on the upper surface of the web filter 52 in the cavity 42 So that it can be formed. The substrate 40 can be any device capable of mounting the light emitting element 44 at a high density. The substrate 40 may be made of, for example, alumina, quartz, calcium zirconate, forsterite, SiC, graphite, fused silica, mullite, Cordierite, zirconia, beryllia, and aluminum nitride, low temperature co-fired ceramic (LTCC), high temperature co-fired ceramic (HTCC) Varistors and the like. In particular, ZnO-based varistors have high thermal conductivity. When the varistor material is made of ZnO as a main component, it functions not only as a varistor but also can quickly lower the temperature of the LED package due to the high thermal conductivity of the varistor itself. In the first embodiment, the substrate 40 is set to be an LTCC substrate. The cavity 42 may have a cylindrical shape or a rectangular shape. If necessary, the shape of the cavity 42 may be different from the shape described above. Although the light emitting device 44 is electrically connected to the anode (not shown) and the cathode (not shown) using two wires 46 in FIG. 4, for example, the light emitting device 44 may be eutectic bonding The number of wires may be one. On the other hand, if the light emitting element 44 is a light emitting element capable of flip bonding, the wire 46 may not be required.

Next, as shown in FIG. 5, a transparent resin such as silicon is filled in the cavity 42 so that the light emitting element 44 is embedded. For example, it is filled up to the height of the stepped portion of the cavity 42. The transparent resin layer 48 is formed in the cavity 42 by filling the transparent resin. At this time, the upper surface of the transparent resin layer 48 is filled so as to be concave. Concave the upper surface of the transparent resin layer 48 is for facilitating the subsequent installation of the web filter 52.

Thereafter, as shown in FIG. 6, oven cure is performed to cure the silicon of the transparent resin layer 48. The temperature of the oven curing is about 120 ° C, and it is carried out for 5 to 10 minutes. Silicon begins to cure from about 120 ° C, so it cures in a gel state rather than a full cure (ie, cure until the silicon is fully cured). For example, if the silicon filter is completely filled up to the lower portion of the position where the web filter 52 is to be disposed and hardened, and then the web filter 52 is disposed on the web filter 52 and then cured again, delamination And the web filter 52 may be deformed by the high temperature. Therefore, the transparent resin layer 48 is cured in a gel state in order to prevent later deformation or dilemination as much as possible.

Then, as shown in FIG. 7, a concave portion of the upper surface of the transparent resin layer 48 is filled with a transparent resin 50 such as liquid silicon. The portion filled with the transparent resin 50 is referred to as a transparent resin layer, and the reference numeral of the transparent resin layer formed by the transparent resin 50 is referred to as "50" for the sake of convenience.

Thereafter, the web filter 52 is disposed flat thereon. That is, as shown in FIG. 8, the rim portion of the web filter 52 of a predetermined size is placed on the step 43 in the cavity 42. Here, the web filter 52 has a plurality of fibers in a spongy form (for example, a nonwoven fabric form) as shown in Figs. 11 and 12. Thus, the liquid silicone (that is, the silicone of the transparent resin layer 50) under the web filter 52 seeps into the web filter 52 by the osmotic pressure phenomenon. Thus, the web filter 52 is completely adhered to the lower transparent resin layer 50. When a general thin film is placed on the transparent resin layer 50, air bubbles are not generated because they are not in close contact with each other. However, the web filter 52 in the present invention has a very large absorption capacity because a plurality of nanometer-diameter fibers are formed in a sparse form. This ensures that the voids between the fibers and the fibers are completely filled with the silicone so that no air bubbles are generated. The web filter 52 is made of a plurality of fibers in coarse form (see Figs. 11 and 12) by electrospinning. The web filter 52 is made of a mixed solution containing a polymer and a phosphor (capable of being in the form of a powder or a solution) and a solvent (for example, a solvent). The polymer in the first embodiment is transparent and has excellent light transmittance, and any one of TPU (Thermal Polyurethane), PC (Polycarbonate) and PMMA (Polymethyl methacrylate) is used. TPU, PC, and PMMA have a softening point of at least about 100 ° C to ensure heat resistance. For example, in the case of PMMA, it is preferable to use an optical grade or LCD grade PMMA having a softening point of about 100 ° C or higher. The reason for ensuring the heat resistance of the polymer is to minimize the deformation of the web filter 52 from the heat generated by the driving of the light emitting element 44. [ In the first embodiment, any one of TPU, PC, and PMMA is used. However, other materials may be used as long as they can take the form of the web filter 52 as in the present invention. The mixed solution is a mixture of about 10 to 40 wt% of a polymer and about 50 to 300 wt% of a phosphor and about 60 to 90 wt% of a solvent (e.g., DMAc (Dimethylacetamide), acetone, etc.) relative to the polymer. The mixed solution is stretched by an electric field, for example, from a spinneret or a spray nozzle to a grounded collector. A jet flow of the mixed solution from the spinneret or the injection nozzle to the collector is generated and the mixed solution is sprayed to the collector side by the taylor cone by the jet flow. The configuration from the spinneret or the spray nozzle to the sprayer to the collector side is not shown separately. However, the person skilled in the same kind of industry can understand it with the ordinary knowledge. Thus, a web filter 52 (see Figs. 11 and 12) having a number of nanometer-diameter fibers is produced. Because of its very small diameter, it provides a large specific surface area and has a very large absorption capacity. It is also possible that the desired web filter 52 can be manufactured by a method other than the electrospinning method described above. The web filter 52 of the first embodiment has a thickness of, for example, about 10 to 200 mu m, and each of the plurality of fibers has a diameter of, for example, about 500 nm to 20 mu m. The thickness of the web filter 52 and the diameter of each of the fibers exemplified above may vary depending on the electrospinning condition. As can be seen from Figs. 11 and 12, the phosphors are contained in each of the plurality of fibers. The thickness of the web filter 52 is constant and the ratio of the phosphor is constant per unit area as compared with the conventional dispensing type so that desired color coordinates can be easily obtained. This improves the stability of the color coordinate, thereby eliminating the required color coordinate rank out. That is, by appropriately combining the phosphors, it is possible to provide any LED package having a color coordinate corresponding to the color coordinate required region of the purchaser. In other words, the LED package of the conventional dispensing type has a wide distribution of color coordinates and many unusual products are generated. However, when the above-described web filter 52 is used, a stable color coordinate can be obtained and the generation of unconventional products can be suppressed. Particularly, in comparison with conventional packaging in which a phosphor is coated on a conventional light emitting device, the LED package itself is treated as a defective product when an unconventional product occurs, but the present invention can be applied to, for example, a test result of the web filter 52 Accordingly, only the web filter to be subjected to the outlier processing is processed as a defective product. Accordingly, the present invention can reduce the ratio of discarding the LED package compared to the prior art, thereby improving the production yield.

However, in the first embodiment, the light emitting element 44 and the web filter 52 are spaced apart from each other in the first embodiment. However, in the conventional LED package, the light emitting element and the phosphor are in direct contact with each other, Thereby suppressing deterioration of the phosphor. In terms of long-term reliability, it provides effects such as providing uniform color coordinates, eliminating the yellow ring and reducing the amount of light very little, or providing long-term white light. On the other hand, there is an LED package in which a phosphor layer is applied to the upper surface of a transparent substrate such as glass and is spaced apart from the upper portion of the light emitting device. However, in this case, too, the transparent substrate is deteriorated by heat of the light emitting device Deterioration phenomenon also occurs in the phosphor layer. However, in the first embodiment, since the web filter 52 is used without using the transparent substrate, the degradation phenomenon is remarkably reduced as compared with the LED package coated with the phosphor layer on the transparent substrate.

In addition, the web filter 52 has a plurality of fibers in a sparse form like a nonwoven fabric, and silicon penetrates into voids between the fibers and the fibers, thereby increasing the refractive index and the transmittance. This causes irregular reflection of light passing through the web filter 52, and diffusion of light is performed by irregular reflection. In addition, the amount of light is amplified by the phosphor particles contained in each fiber of the LED package in which the web filter 52 is employed, so that the amount of light is not lowered compared to the conventional dispensing type LED package.

After the web filter 52 is disposed, an oven cure is performed as shown in FIG. 9 to couple the transparent resin layer 50 and the web filter 52 together. Even in this case, the temperature of the oven curing is set at about 120 ° C for about 5 to 10 minutes. The silicon of the transparent resin layer 50 starts to cure at about 120 ° C., so that the cure is finished in a gel state, not a complete cure (ie, cure until the silicon is completely cured). This is to match the physical properties of the lower transparent resin layer 48. For example, if the silicon of the transparent resin layer 50 is hardened, interface separation and delamination may occur between the lower transparent resin layer 48 and the upper transparent resin layer 50, The filter 52 may be deformed by the high temperature. Therefore, the transparent resin layer 50 is cured in a gel state so as to match the physical properties of the underlying transparent resin layer 48 in order to prevent later deformation or delimination.

10, a transparent resin layer 54 is formed on the web filter 52 using silicon and / or a diffuser. Here, the transparent resin layer 54 serves to protect the web filter 52 from an external impact or the like. If the transparent resin layer 54 is made of silicon alone, even if the amount of silicon in the transparent resin layer 50 is insufficient to sufficiently penetrate into the web filter 52, the silicon of the transparent resin layer 54 Permeates into the web filter 52 to remove bubbles. When the transparent resin layer 54 is formed by mixing silicon and a diffuser, the effect obtained when the silicon resin is filled only with silicon is obtained, and the effect of yellow ring removal is doubled through light diffusion. After the transparent resin layer 54 is formed, normal curing is performed according to the curing condition of the general silicon. Thereby, the LED package is completed.

In the above-described first embodiment, an LED package in which one light emitting device 44 is packaged is taken as an example. However, when the LED package is applied to a plurality of LED packages in which a plurality of light emitting devices are arrayed, That is, in a conventional lighting apparatus employing an LED package having a plurality of light emitting elements arranged therein as a light source, each part in which a light emitting element is located is seen as a dot when viewed from the outside. Although a plurality of light emitting devices are required to serve as one light source, a portion where each light emitting device is located is displayed in a dot shape, which gives a visually very bad feeling. However, even when the LED package according to the first embodiment of the present invention is an LED package in which a plurality of light emitting devices are arrayed, the dot phenomenon is eliminated due to the diffuse reflection effect in the web filter 52. In addition, when the web filter 52 is installed in an LED package in which a plurality of light emitting devices are arrayed, the web filter can be cut in accordance with a size to be installed and installed in the cavity, which simplifies the manufacturing process. On the other hand, even when a plurality of LED packages according to the first embodiment of the present invention are arranged, the dot phenomenon is not generated due to the diffuse reflection effect of each of the LED packages in the web filter 52.

(Second Embodiment)

FIG. 13 is a view showing a configuration of an LED package according to a second embodiment of the present invention. Since most of the components of the LED package of the second embodiment are similar to those of the first embodiment described above, the same reference numerals are given to the constituent elements of the first embodiment and the explanation thereof Is omitted.

In the LED package of the second embodiment, a white reflective layer 56 is additionally formed on the inner wall and the bottom surface of the cavity 42. At this time, the reflective layer 56 is formed on the portion except the region where the light emitting element 44 is mounted. The reflective layer 56 may be formed only on the bottom surface of the cavity 42 (that is, the bottom surface excluding the region where the light emitting element 44 is mounted), if necessary.

The reflective layer 56 has a thermosetting property. When the substrate 40 is made of plastic, since the plastic is usually weak to heat, when the substrate 40 is used for a long time, the substrate 40 is deformed and the efficiency of the product (electronic component package) is lowered. However, if the reflection layer 56 is formed using a material having a thermosetting property and is formed in the cavity 42 so as to cover the inner wall and the bottom surface of the cavity 42, Since the portion directly contacting is minimized, the problem caused by the heat generated by the light of the light emitting device 44 is solved. That is, in the second embodiment, even if the substrate 40 is made of plastic, deformation due to heat generation due to use for a long time and deterioration of efficiency are eliminated.

It is preferable that the reflective layer 56 uses, for example, a material having a reflectance of 90% or more (see Table 1 below).

(Table 1)

material

content
Titanium dioxide,
Zinc Oxide,
Lithopone (BaSO ₂ + ZnS)
ZnS,
BaSO ₄ ,
SiO ₂ ,
PTFE (polytetrafluoroethylene)




5 to 60 wt%
Silicone resin (Resin)

5 to 30 wt%
Additives such as solvents,
Epoxy resin etc.

20 to 65 wt%

In Table 1, white TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , PTFE (polytetrafluoroethylene) and the like were used as materials with good reflectivity. Needless to say, other materials may be additionally used, if necessary. For example, other materials may be used instead of ZnS, BaSO ₄ , PTFE (polytetrafluoroethylene). Silicone resin and epoxy resin were used for viscosity and tackiness. In Table 1, TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , PTFE (polytetrafluoroethylene) and the like are used for white color and main material having excellent reflectance. Silicone resin and epoxy resin And so on. In Table 1, it is difficult to realize white when TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ and PTFE (polytetrafluoroethylene) are used in an amount of less than 5% by weight. If more than 60% by weight of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ and PTFE (polytetrafluoroethylene) is used, the addition amount of the silicone resin and epoxy resin becomes small, It is difficult to obtain adhesiveness. If the silicone resin is used in an amount of less than 5% by weight, the viscosity becomes too low. When the silicone resin is used in an amount exceeding 30% by weight, the viscosity becomes too high. When the epoxy resin or the like is used in an amount of less than 20% by weight, the adhesive strength is weakened. When an epoxy resin or the like is used in an amount exceeding 65% by weight, the content of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , PTFE (polytetrafluoroethylene) This makes it difficult or impossible to obtain the desired viscosity.

It is advantageous that the reflection layer 56 is white for the purpose of increasing the amount of light. The white light must be absorbed. A reflection layer 56 is formed by selecting TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , PTFE (polytetrafluoroethylene) having low light absorption and good reflectivity, Not only the light absorption is reduced but also almost all of the light from the light emitting element 44 is reflected, thereby improving the light efficiency (increasing the light amount).

When the reflection layer 56 is formed in such a manner that the reflection layer 56 is rounded inward, almost all of the light from the light emitting element 44 is reflected by the reflection layer 56 without loss and is output. As a result, the amount of white light emitted through the web filter 52 is further increased as compared with the case where the reflective layer 56 is not used.

Even if the manufacturing process for the LED package of the second embodiment is not separately described, a person who is engaged in the same kind of industry can fully grasp it based on the description of the manufacturing process in the first embodiment. The reflective layer 56 may be formed after mounting the light emitting element 44 on the cavity 42 and bonding the wires 46 thereto. That is, it may be performed before forming the transparent resin layer 48. In other words, the reflective layer 56 may be formed between the process based on Fig. 4 and the process based on Fig.

The LED package of the second embodiment not only achieves the same effect as that of the LED package of the first embodiment but also allows the reflective layer 56 to obtain a larger amount of light.

Although the web filter 52 is placed on the step 43 in the first and second embodiments described above, the upper opening of the cavity 42 may be covered if necessary.

14 to 16 are data sheets of a general dispensing type LED package and an LED package according to an embodiment of the present invention. FIG. 14 is a data sheet of a general dispensing type LED package, and FIGS. 15 and 16 Is a data sheet for an LED package according to an embodiment of the present invention.

14, 15 and 16, I _F is the forward rated current of the light emitting device (LED chip), and V _F is the forward rated voltage of the light emitting device (LED chip). Chrom x and Chrom y are the color coordinates x, y of the CIE 1941 standard. The distance between the bone and the bone is referred to as the wavelength in the wave when observing the periodically visible wave that repeats the shape with the flow of time stopped. The peak wave means the point where the light of the LED source measured by applying the current is highest (that is, the apex of the wavelength), and the end point of the extension line with the LED source measured by applying the current from the center of the CIE diagram It means the place to meet. Color Tem is the color temperature, and Gen CRI is the color rendering property. IV is the intensity of light and indicates how much light is emitted in a certain direction from the light source. TLF (Total Luninous Flux) is the total amount of light emitted by a light source and sensed by the eye. Efficacy is the total power output of the light emitted from the light source and sensed by the eye divided by the applied voltage and current. Efficieacy is a value obtained by dividing the amount of light output from the light source by the applied voltage and current. Expressing Efficieacy as: ((I _F * V _F / 1000)) / output as light ".

FIG. 17 is a graph comparing light quantities of a general dispensing type LED package and an LED package according to an embodiment of the present invention, based on the data sheets of FIGS. 14 to 16. FIG.

As can be seen from the graph of FIG. 17, the LED package according to the embodiment of the present invention is similar in light quantity or about 5% higher than the general dispensing type LED package. Therefore, the LED package according to the embodiment of the present invention can sufficiently replace the conventional LED package.

18 is a graph showing distribution of color coordinates of a general dispensing type LED package and an LED package according to an embodiment of the present invention, based on the data sheets of FIGS. 14 to 16. FIG.

As can be seen from the graph of FIG. 18, the LED package of the general dispensing type has a wide distribution of color coordinate ranks. In this case, an LED package having a color coordinate belonging to a color coordinate rank not desired by the customer is processed as an inventory. However, according to the LED package according to the embodiment of the present invention, the distribution of the color coordinate ranks can be adjusted to the specification of the customer by adopting the web filter. That is, when the amount of the fluorescent material of the web filter 52 of the present invention is adjusted, the LED package according to the embodiment of the present invention can minimize the out-of-order occurrence of the color coordinate rank desired by the customer. This can significantly reduce inventory. In other words, in the LED package according to the embodiment of the present invention, the ratio of the phosphor of the web filter 52 is constant per unit area, so that not only the desired color coordinates but also the effect of removing the yellow ring is obtained incidentally.

19 is a data sheet showing the reliability test results of the normal dispensing type LED package and the LED package according to the embodiment of the present invention. 20 is a graph comparing the reliability of a normal dispensing type LED package and an LED package according to an embodiment of the present invention, at room temperature, according to the data sheet of FIG.

In Fig. 19, A and B classes are separated from the phosphor portion. The A class is higher quality than the B class. Accordingly, the conventional A-class dispensing type LED package is an LED package using a class A phosphor, and the conventional B-class dispensing type LED package means an LED package using a class B phosphor. The chip uses a blue LED chip, and the phosphor uses a yellow phosphor.

As can be seen from the graph of FIG. 20, when the conventional LED package of the A-class and B-class dispensing type is continuously operated at room temperature for a long time, the amount of light decreases as time elapses. There is almost no reduction in the amount of light. That is, the LED packages of the A-class and B-class dispensing type in the related art cause a decrease in light quantity and yellowing due to the deterioration of the phosphor due to heat generated in the light emitting device. However, in the LED package according to the embodiment of the present invention, a web filter made of a material having a high transmittance is installed apart from the light emitting device, thereby suppressing deterioration of the phosphor due to heat generated in the light emitting device, Minimizing the occurrence of yellow rings.

Therefore, it can be seen that the LED package according to the embodiment of the present invention is more reliable than the conventional LED package in terms of long-term reliability.

Although the light emitting device 44 and the web filter 52 are spaced apart from each other in the above embodiments of the present invention, the web filter 52 may be directly attached to the upper surface of the light emitting device 44 if necessary. This has the advantage that the manufacturing process becomes much simpler compared to a method of coating a phosphor on a conventional LED chip (in this case, it is very difficult to uniformly coat the phosphor).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. You must see.

1 is a cross-sectional view showing a configuration of a general LED package.

2 is a view for explaining a problem of a conventional LED package.

3A is an example of a data sheet including color coordinate data of a conventional LED package.

3B is an example of a color coordinate graph for a conventional LED package.

FIGS. 4 to 10 are views for explaining the configuration and manufacturing process of the LED package according to the first embodiment of the present invention.

11 is a photograph of the web filter of the first embodiment of the present invention.

12 is an enlarged photograph of a part of the web filter of Fig.

FIG. 13 is a view showing a configuration of an LED package according to a second embodiment of the present invention.

14 to 16 are data sheets of a general dispensing type LED package and an LED package according to an embodiment of the present invention. FIG. 14 is a data sheet of a general dispensing type LED package, and FIGS. 15 and 16 Is a data sheet for an LED package according to an embodiment of the present invention.

FIG. 17 is a graph comparing light quantities of a general dispensing type LED package and an LED package according to an embodiment of the present invention, based on the data sheets of FIGS. 14 to 16. FIG.

18 is a graph showing distribution of color coordinates of a general dispensing type LED package and an LED package according to an embodiment of the present invention, based on the data sheets of FIGS. 14 to 16. FIG.

19 is a data sheet showing the reliability test results of the normal dispensing type LED package and the LED package according to the embodiment of the present invention.

20 is a graph comparing the reliability of a normal dispensing type LED package and an LED package according to an embodiment of the present invention, at room temperature, according to the data sheet of FIG.

Claims (32)

A light emitting element; A substrate having a cavity in which the light emitting device is mounted; A web filter provided on an upper portion of the light emitting device so as to be spaced apart from the light emitting device in the cavity and made of a mixed solution containing a polymer, a fluorescent material, and a solvent as a raw material, And And a transparent resin layer formed between the light emitting element and the web filter, Wherein the transparent resin layer comprises: A transparent resin in which the light emitting element is primarily filled in the cavity in which the light emitting element is mounted, and the upper surface is concave; And Wherein the transparent resin is thermally treated so that the transparent resin is in a gel state, and then the transparent resin is secondarily charged on the heat-treated transparent resin. The method according to claim 1, Wherein a transparent resin layer using silicon and / or a diffuser is further formed on the web filter. The method according to claim 1, Wherein the web filter includes the phosphor in each of the plurality of fibers. The method according to claim 1, Wherein the polymer is one of TPU (Thermal Polyurethane), PC (Polycarbonate), and PMMA (Polymethyl methacrylate). The method according to claim 1, Wherein the mixed solution comprises 10 to 40% by weight of the polymer and 50 to 300% by weight of the fluorescent material with respect to the polymer. The method according to claim 1, Wherein each of the plurality of fibers has a diameter of 500 nm to 20 占 퐉. The method according to claim 1, Wherein the web filter has a thickness of 10 to 200 占 퐉. The method according to any one of claims 1 to 7, Further comprising a white reflective layer formed on the cavity so as to cover only the inner wall, the bottom surface, or the bottom surface of the cavity except a region where the light emitting device is mounted. The method of claim 8, Wherein the reflective layer is rounded inwardly. The method of claim 8, Wherein the reflective layer comprises at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene). The method of claim 8, Wherein the reflective layer contains at least one of TiO ₂ , ZnO, Lithopone, ZnS, BaSO ₄ , SiO ₂ , and PTFE (polytetrafluoroethylene) as a main material, and the main material is added in an amount of 5 to 60 wt% The LED package. The method of claim 11, Wherein the reflective layer comprises a core material in which a silicone resin is 5 to 30 wt% and an epoxy resin is 20 to 65 wt% together with the main material. A web filter preparation step of preparing a web filter in which a plurality of fibers are formed into a coarse shape by electrospinning using a mixed solution containing a polymer, a phosphor and a solvent as a raw material; A light emitting element mounting step of mounting the light emitting element on the bottom surface of the cavity of the substrate; A transparent resin layer forming step of filling a cavity in which the light emitting device is mounted with a transparent resin to form a transparent resin layer; And And attaching the web filter to the upper surface of the transparent resin layer, The transparent resin layer forming step may include: A transparent resin primary charging step of filling the upper surface of the transparent resin to be filled in the cavity with the light emitting element being recessed and filling the light emitting element so as to be embedded; A transparent resin heat treatment step of performing heat treatment so that the filled transparent resin is in a gel state; And And a transparent resin secondary filling step of filling the upper surface of the recessed transparent resin with a transparent resin again. delete 14. The method of claim 13, And forming a transparent resin layer using silicon and / or a diffuser on the upper portion of the web filter. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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