KR100894168B1 - Phosphor filter, method of manufacturing phosphor filter, semiconductor package using phosphor filter, and method of manufacturing semiconductor package using phosphor filter - Google Patents

Abstract

A phosphor filter, a method for manufacturing the same, a semiconductor package using the same, and a method for manufacturing the semiconductor package are provided to remove a yellow band by installing the phosphor filter to reduce an area of a phosphor layer in a cavity. An LED package includes a substrate(40) with a cavity(46), an LED chip(42) mounted in a light emitting element mounting region inside the cavity, a wire(44) electrically connecting the LED chip to a pattern electrode, and a phosphor filter(110) horizontally installed in the upper part of the LED chip. The cavity of the substrate is divided to an upper cavity(46a) and a lower cavity(46b). The phosphor filter covers the opening of the lower cavity. A medium(48) is located in the space between the phosphor filter and the LED chip. A diffusion layer(56) is formed in the upper side of the phosphor filter.

Description

Phosphor filter, method of manufacturing phosphor filter, semiconductor package using phosphor filter, and method of manufacturing semiconductor package using phosphor filter

The present invention relates to a phosphor filter, a method for manufacturing the same, and a method for manufacturing a semiconductor package using the phosphor filter and a semiconductor package using the phosphor filter. It relates to a semiconductor package using and a method for manufacturing a semiconductor package using a phosphor filter.

In general, a method of implementing a white LED by being used in a luminaire or the like includes a method of combining a blue LED chip having a wavelength of approximately 430 nm to 470 nm in a visible light region with a YAG-based phosphor (eg, yellow phosphor), and a UV LED chip. And a method of combining red / green / blue phosphors, and a method of combining red / green / blue LED chips. The first method is often used due to the low cost and high efficiency of white LEDs.

When a white LED is implemented by combining a blue LED chip and a YAG-based phosphor (eg, yellow phosphor), the structure is illustrated in FIG. 1.

The LED package of Figure 1, the 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 the 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 chips 14 via wires 16; And a phosphor layer 18 charged to cover the LED chip 14 after phosphors (eg, yellow phosphor) and silicon (or epoxy) are blended according to a predetermined compounding 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, manufacturers adopt various methods.

Among them, a method that is frequently used is a method of doping phosphors in the vicinity of the LED chip 14 using a syringe (not shown). Devices that use this method are commonly referred to as dispensers.

The LED package manufactured by the dispenser is most preferably such that the upper surface of the phosphor layer 18 filled in the cavity formed in the substrate 30 is horizontal as shown in FIG. However, the horizontal mold of the phosphor layer 18 is difficult due to the amount of phosphor, liquid phase tension, and the like, which are doped with a syringe (not shown). As the amount of phosphor to be doped is large and small, the upper surface of the phosphor layer 18 is concave as shown in FIG. 2A or convex as shown in FIG. As a result, the color coordinate distribution of LED packages manufactured by the dispenser is wide. This means that a large amount of extraneous products continue to occur.

Even when looking at the graph (refer to FIG. 3B) based on the color coordinate data (chrom x, chrom y) on the data sheet of FIG. 3A, it can be seen that the ratio classified as the outlier (A) is high.

Since the thickness of the phosphor layer 18 surrounding the LED chip 14 is not constant, the irregular product causes a change in the path through which the light generated from the LED chip 14 passes through the phosphor layer 18. This means that when a light shines on a subject, a yellow ring is generated along an edge of the light shining. Not only does the yellow band not look good, but it is also a major cause of deterioration of the quality of the picture when taking pictures in ordinary camera flash.

In other words, if all the light emitting surfaces of the LED chip 14 are surrounded by a phosphor layer of uniform thickness, the length of the movement path until the light emitted from the LED chip 14 passes through the phosphor layer in any direction. Are all the same, and yellow bands will not be generated. However, in the case of an extraneous product, the yellow bands are generated along the edge where light is emitted because the thickness of the phosphor layer surrounding the LED chip 14 is uneven. Therefore, there exists a problem that light efficiency falls.

Thus, the applicant has proposed an LED package as shown in Figure 4 as a configuration for removing the yellow stripe.

The LED package of FIG. 4 includes a substrate 100 having a cavity formed therein; An LED chip 14 mounted in the light emitting element mounting region in the cavity; A wire 16 electrically connecting the LED chip 14 to a pattern electrode (not shown); And a phosphor filter 108 horizontally disposed to be spaced apart from the LED chip 14 at the top of the LED chip 14. The phosphor filter 108 includes a transparent glass 104 of a flat plate; And the phosphor layer 106 formed on the upper surface of the transparent glass 104. The size (width * length) of the transparent glass 104 and the size (width * length) of the phosphor layer 106 are the same.

According to the configuration as shown in FIG. 4, the transparent glass 104 is formed horizontally in a flat plate, and the phosphor layer 106 is formed on the upper surface of the transparent glass 104 with a uniform thickness. This configuration simply solves the problem of the conventional horizontal mold. As a result, since the light emitted from the LED chip 14 passes through the phosphor filter 108 having a uniform thickness, the color coordinate dispersion is stabilized, which greatly contributes to the yield improvement.

As a result of experiments without the lens attached to the configuration of FIG. 4, the generation of yellow bands can be confirmed by the measuring equipment and the like even though the generation of yellow bands is hardly recognized by humans. That is, the luminous flux emitted to the side of the LED chip 14 is less than about 10%, the light intensity is weak. Such light becomes yellow when passing through the phosphor layer 106. In addition, as a result of attaching the lens and experimenting, the occurrence of some blue bands was confirmed.

In this regard, the Applicant has conducted research and experiments for removing yellow bands at various angles. As one of them, the experiment was performed by applying black ink 109 to the edge of the phosphor filter as shown in FIG. As a result, as shown in Figure 5 (b) it was found that the yellow strip is completely removed.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-described conventional circumstances, and provides a phosphor filter and a method for manufacturing the semiconductor package using the phosphor filter and a method for manufacturing the semiconductor package using the phosphor filter to completely eliminate yellow band generation. The purpose is.

In order to achieve the above object, a method of manufacturing a semiconductor package using a phosphor filter according to a preferred embodiment of the present invention includes preparing a phosphor filter by forming a phosphor layer having a smaller area than that of the transparent substrate on a transparent substrate of a plate. The first process of doing; Preparing a substrate including a cavity having an area larger than that of the phosphor layer; A third step of mounting a light emitting element on the bottom of the cavity; And a fourth process of installing a phosphor filter on the cavity in which the light emitting device is mounted.

In the first process, a dam is formed on a transparent substrate and a phosphor layer is filled in the dam.

In the first step, the transparent base material is etched to form a filling portion, and the phosphor layer is filled in the filling portion.

In a semiconductor package using a phosphor filter according to an embodiment of the present invention, in a semiconductor package including a cavity having a light emitting element mounting region,

A light emitting device mounted on a light emitting device mounting region; And a phosphor filter having a transparent substrate on the plate and a phosphor layer formed on the transparent substrate, the phosphor filter being installed on an upper portion of the cavity,

The area of the phosphor layer is small compared to the area of the cavity.

A dam is formed around the phosphor layer, and the phosphor layer is filled inside the dam.

A charging unit is formed on one surface of the transparent substrate, and the phosphor layer is filled inside the charging unit.

A medium is filled between the light emitting element and the phosphor filter, and a part of the filled medium and the phosphor filter do not overlap each other.

A diffusion layer is further formed on top of the phosphor filter.

The area of the phosphor layer is determined according to the directivity angle of the light emitting element and the amount of light emitted toward the front of the light emitting element.

Phosphor filter according to an embodiment of the present invention, the transparent substrate of the flat plate; And a phosphor layer formed on one surface of the transparent substrate and having a smaller area than the transparent substrate.

The phosphor layer is surrounded by a dam.

The phosphor layer is filled in the charging unit formed concave on one surface of the transparent substrate.

A method of manufacturing a phosphor filter according to an embodiment of the present invention, the first process of preparing a transparent substrate of the plate; And a second process of forming a phosphor layer having a smaller area than that of the transparent substrate on one surface of the transparent substrate.

In the second process, a dam is formed on one surface of the transparent substrate and the phosphor layer is filled in the dam.

In the second process, a charging unit is formed on one surface of the transparent substrate and the phosphor layer is filled in the charging unit.

The second process is filled using any one of a squeeze method, a spin coating method, a dotting method, and a spray method.

According to the present invention having such a configuration, the yellow light band is eliminated when the light emitting device emits light by installing a phosphor filter in the cavity in which the area of the phosphor layer formed on the transparent substrate of the plate is smaller than the area of the opening of the cavity. .

Compared with the prior art, the dispersion of color coordinates is stabilized. This significantly reduces the incidence of isochronous products and improves the yield.

Compared with the conventional method, the light efficiency is improved.

Hereinafter, a phosphor filter, a manufacturing method thereof, and a semiconductor package using the phosphor filter of the present invention will be described with reference to the accompanying drawings. Hereinafter, the LED package will be described as an optimal embodiment. In addition, the LED package may be applied to all SMD type packages such as ceramic packages, plastic packages, lead frame type packages, and plastic + lead frame type packages.

The area of the phosphor layer according to the claims of the present invention means an application region of the phosphor layer applied to one surface of the transparent glass. If the phosphor layer is formed in a circular shape, it will have a predetermined diameter, and if the phosphor layer has a rectangular shape, it will have a predetermined size (horizontal * vertical). In other words, in the present invention, the phosphor layer does not cover all of one surface of the transparent glass but covers the remaining portions except the edge portion of one surface of the transparent glass. Thus, the area | region to which the fluorescent substance layer was apply | coated on one surface of transparent glass may be considered as the area of a fluorescent substance layer.

The area of the cavity described in the claims of the present invention means the area of the lower cavity of the following example, and means the diameter or the size (horizontal * vertical) of the opening of the lower cavity in which the phosphor filter is installed. Of course, when the cavity is not partitioned into the upper cavity and the lower cavity and is one cavity of the same diameter or size, it means the diameter or size (horizontal * vertical) of the opening of the one cavity. Therefore, the fact that the area of the phosphor layer described in the claims is smaller than the area of the cavity expresses that the phosphor layer covers the remaining area except for the edge portion of the cavity rather than covering all the openings of the cavity. In addition, the fact that the area of the phosphor layer according to the claims of the present invention is smaller than that of the transparent base material does not cover the entire surface of the transparent base material (transparent glass) but rather the edge of one side of the transparent base material (transparent glass). It is understood that the expression represents covering the remaining area except for the above.

The following embodiments start with removing the area occupied by the black ink part, paying attention to the phenomenon that the yellow band is completely removed when the black ink is painted on the edge of the phosphor filter as shown in FIG. 5.

(First embodiment)

6 and 7 are views for explaining the configuration of the phosphor filter and the semiconductor package using the same according to the first embodiment of the present invention.

The phosphor filter 110 of the first embodiment includes a transparent glass 105 of a flat plate; And a phosphor layer 107 formed on one surface (upper surface) of the transparent glass 105.

The transparent glass 105 has a light transmittance of a predetermined value or more (eg, 90% or more). The transparent glass 105 is AR coated to improve light transmittance. In addition, the transparent glass 105 is thermally strengthened.

The phosphor used for the phosphor layer 107 is a yellow phosphor. This is a case where the LED chip 42 outputs blue light, and is for making white light. If the color of the light output from the LED chip 42 is not blue, the color of the phosphor should also be changed to produce white light.

The phosphor layer 107 has a square shape and has a smaller area than that of the transparent glass 105. For example, in the first embodiment, the size of the transparent glass 105 is approximately 3.0 * 3.0 mm, and the size of the phosphor layer 107 is approximately 1.6 * 1.6 mm. These numbers were obtained by experiment.

The phosphor layer 107 is advantageously formed on the upper surface of the transparent glass 105 as compared to that formed on the bottom surface. This is also the case in other embodiments to be described later. This is because when the phosphor layer 107 is at the bottom of the transparent glass 105, diffuse reflection is performed inside the transparent glass 105 until light passing through the phosphor layer 107 passes through the transparent glass 105. . When the phosphor layer 107 is located on the upper surface of the transparent glass 105, the light passing through the phosphor layer 107 immediately goes to the outside so that no diffuse reflection occurs. When the phosphor layer 107 is on the bottom of the transparent glass 105, there is a possibility that deterioration may occur due to heat from the LED chip 42. In the phosphor layer 107, granular phosphor and silicon (or epoxy) are blended at a predetermined compounding ratio.

When the LED package is completed by using the phosphor filter 110 of the first embodiment, it becomes as shown in FIG. 7.

The LED package of the first embodiment includes a substrate 40 having a cavity 46 formed therein; An LED chip 42 mounted in a light emitting element mounting region in the cavity 46; A wire 44 for electrically connecting the LED chip 42 to a pattern electrode (not shown); And a phosphor filter 110 horizontally installed to be spaced apart from the LED chip 42 on the upper part of the LED chip 42.

The board | substrate 40 should just be a board | substrate which can mount the LED chip 42 in high density. For example, alumina, quartz, calcium zirconate, forsterite, SiC, graphite, fusedsilica, mullite, cordierite, zirconia Zirconia, beryllia, aluminum nitride, low temperature co-fired ceramic (LTCC), and the like may be the material of the substrate 40. In addition, the ESD protection function may be additionally implemented by configuring the substrate 40 using a varistor material.

The cavity 46 of the substrate 40 is divided into an upper cavity 46a and a lower cavity 46b. The size or diameter of the upper cavity 46a is larger than the size or diameter of the lower cavity 46b. The upper cavity 46a and the lower cavity 46b are formed in a rectangular cross-sectional structure.

The phosphor filter 110 covers the opening of the lower cavity 46b. The size (horizontal * vertical) of the phosphor layer 107 of the phosphor filter 110 is smaller than the area of the lower cavity 46b.

The LED chip 42 is mounted in the light emitting element mounting region in the lower cavity 46b. Most preferably, the distance between both sides of the LED chip 42 and the side surface of the lower cavity 46b facing it and the distance between the upper surface of the LED chip 42 and the lower surface of the phosphor filter facing the LED chip 42 are the same.

A medium (eg, air or silicon (or epoxy)) 48 is accommodated in the space between the LED chip 42 and the phosphor filter 110. The use of transparent silicon in the medium 48 is superior in light efficiency to air.

A diffusion layer 56 is further formed on the upper surface of the phosphor filter 110. In the diffusion layer 56, for example, a diffuser of Al ₂ O ₃ and silicon (or epoxy) are blended at a predetermined compounding ratio. Since there may be a change in optical characteristics according to the blending ratio of the diffuser, the range for the blending ratio of the diffuser may be determined in consideration of the optical characteristics. In practice the diffuser has a cross section, for example a star or a cogwheel. The reflection (scattering) of the light by the diffuser occurs in the diffusion layer 56 to obtain the effect of diffusion. The diffusion layer 56 is an incidental element to further increase the accuracy of the removal of the yellow band. If necessary, the diffusion layer 56 may be left without air.

8 is a photograph showing the results of testing the first embodiment of the present invention. FIG. 8A shows that the phosphor filter having the rectangular phosphor layer 107 is covered by the diffusion layer 56 and thus is invisible. The LED chip 42 was made to emit light after installing the LED package equipped with the phosphor filter as shown in FIG. 8A in the center of the support 112 of FIG. 8B. As a result, it was confirmed that the yellow stripe was removed as shown in FIG.

In the test for the first embodiment, for example, the size of the substrate 40 is 5.0 * 5.0 mm, the size of the upper cavity 46a is 4.0 * 4.0 mm, and the size of the lower cavity 46b is 2.6 * 2.6. mm. The distance between the LED chip 42 and the phosphor layer 107 was approximately 2.8 mm ± 0.3 mm. The directivity angle of the LED chip 42 was 120 degrees. It is assumed that about 90% of the amount of light emitted from the LED chip 42 is incident to the front (i.e., the phosphor filter side) and the remaining 10% of the amount of light is emitted to both sides. Of course, even when the amount of light emitted forward was set to 80% and the amount of light of 20% was emitted to both sides, yellow bands were removed as shown in FIG. In other words, since the area of the phosphor layer 107 on the upper surface of the transparent glass 105 is equal to the angle at which the light source is emitted, yellow and blue bands are not generated.

However, when the LED package employing the phosphor filter of the first embodiment is used for a lighting fixture and a lens is attached, a rectangular light source is generated when viewed from the front, which is not good in appearance. In order to make the thickness of the phosphor layer 107 a desired thickness, several printings should be performed. Even if the printing to the desired thickness, the printing area is generated outside the desired area in the printing process, there is a hassle that additional post-processing occurs. In addition, the drying time also becomes longer as several times of printing.

(Second embodiment)

9 and 10 are views for explaining the configuration of the phosphor filter according to a second embodiment of the present invention. The second embodiment is to eliminate the square light source and simplify the printing process for forming the phosphor layer when attaching the lens generated in the first embodiment.

Compared to the first embodiment, the second embodiment differs only in the shape of the phosphor filter, and all other parts are the same. That is, the phosphor layer 107 of the first embodiment has a square shape, but the phosphor layer 107 of the second embodiment has a circular shape.

The configuration of the semiconductor package (LED package) according to the second embodiment is not shown in the drawings. Those skilled in the art can readily see that the desired LED package can be obtained by applying the phosphor filter 110 having the circular phosphor layer 107 to the substrate of the first embodiment as it is.

In the second embodiment, the phosphor was doped to form a circular phosphor layer 107. It is easier to form the phosphor layer by adopting the dotting method instead of the printing method. In the second embodiment, as the phosphor is doped, the phosphor spreads widely on the upper surface of the transparent glass 105. When the phosphor is doped, the phosphor content is approximately 45% to 55%. If the size of the transparent glass 105 is assumed to be approximately 3.0 * 3.0 mm, the diameter of the phosphor layer 107 of the second embodiment is approximately 1.8 mm. The phosphor layer 107 of the second embodiment is slightly smaller in thickness than the center portion as illustrated in FIG.

When the amount of the yellow phosphor used for the phosphor layer 107 was approximately 45%, 50%, and 55%, it was confirmed that the yellow band was removed.

11 is a photograph showing the results of testing the second embodiment of the present invention. FIG. 11A illustrates a case where the content of the phosphor is 45%, FIG. 11B illustrates a case where the phosphor content is 50%, and FIG. 11C illustrates a phosphor content of 55%. One case. In the test for the second embodiment, the size of the substrate 40 and the area of the cavity 46 were the same as in the first embodiment. The distance between the LED chip 42 and the phosphor layer 107, the direction angle of the LED chip 42, and the amount of emitted light (90% in front and 10% in both sides) are the same as in the first embodiment. It was.

Referring to the photograph of FIG. 11, it can be seen that generation of the square light source and generation of the yellow band are removed according to the second embodiment. In other words, since the area of the phosphor layer 107 on the upper surface of the transparent glass 105 is equal to the angle at which the light source is emitted, no yellow band is generated.

However, in the second embodiment, as the phosphor is widely applied on the upper surface of the transparent glass 105, it is rather difficult to accurately match the desired color coordinates. The color coordinates according to the second embodiment are somewhat lower than the other embodiments. In addition, as the edge portion of the phosphor layer 107 is slightly sag compared to the center portion, a blue band may be generated at the edge portion of the light source.

(Third Embodiment)

12 and 13 are views for explaining the configuration of the phosphor filter according to the third embodiment of the present invention. FIG. 12 is a cross-sectional view of the phosphor filter, and FIG. 12 is a plan view of the phosphor filter. The configuration of the semiconductor package (LED package) according to the third embodiment is not shown in the drawings. Those skilled in the art can readily appreciate that if the phosphor filter 110 of the third embodiment to be described below is applied to the substrate of the first embodiment, a desired LED package can be obtained.

The phosphor filter of the third embodiment is implemented to remove sagging of the edge portion of the phosphor layer in the second embodiment and to remove the blue band generated from the edge portion of the light source.

In the phosphor filter 110 of the third embodiment, a circular dam 109 having a predetermined diameter is formed on an upper surface of the transparent glass 105, and a phosphor is filled in the dam 109 to form the phosphor layer 107. . The space formed by the dam 109 is called a charging part.

14 to 20 are views for explaining a process of manufacturing a semiconductor package according to a third embodiment of the present invention.

The jig (not shown) arranges the transparent glass 112 of the flat plate. At this time, the transparent glass 112 was AR-coated in advance to reduce the surface reflectance of the projected light and increase the transmittance, and was thermally strengthened to prevent deformation during later curing and step curing. A plurality of black circular marks 113 are printed on the upper surface of the transparent glass 112 (see FIG. 14).

The phosphor 114 is dispensed into the plurality of circular marks 113 (see FIG. 15), and then curing is performed. Thereafter, as shown in Figure 16 is cut along the cutting line k. The cut line k is not displayed on the transparent glass 112. When the cutter not shown cuts to the programmed size, it is as if the cutter is cutting along the cutting line k. In this way, the phosphor filter of the third embodiment having the cross section as shown in Fig. 17 is subdivided.

14 to 17 illustrate the process of manufacturing the phosphor filter of the third embodiment.

Hereinafter, a process of completing the LED package by installing the phosphor filter of the third embodiment on the substrate will be described.

The wire 44 is bonded by mounting the LED chip 42 in the light emitting element mounting region of the substrate 40 on which the lower cavity 46b and the upper cavity 46a are formed. Then, a medium 48 such as silicon or epoxy is first dispensed into the lower cavity 46b (see FIG. 18). The medium 48 is filled in the lower cavity 46b by primary dispensing.

The phosphor filter 110 united as shown in FIG. 19 is positioned flat on the opening of the lower cavity 46b. The diameter of the phosphor layer 107 of the phosphor filter 110 is smaller than the diameter or area of the opening of the lower cavity 46b. In order to facilitate accurate installation and fixing of the phosphor filter 110, a step (not shown) may be formed in advance at a contact portion between the lower cavity 46b and the upper cavity 46a. Thereafter, step curing is performed. Curing is carried out for approximately one hour at a temperature of approximately 60 ° C. and then for approximately three hours at a temperature of approximately 150 ° C. again. This step curing makes the bonding between the phosphor filter and the substrate firm. This completes the desired semiconductor package.

Of course, the process of forming the diffusion layer 56 may be additionally performed. That is, after the operation up to FIG. 19 is completed, step curing is performed, and as shown in FIG. 20, secondary dispensing for forming the diffusion layer 56 is performed on the upper part of the phosphor filter, and step curing is performed.

Also in the test for the third embodiment, the size of the substrate 40 and the area of the cavity 46 were the same as in the first embodiment. The distance between the LED chip 42 and the phosphor layer 107, the direction angle of the LED chip 42, and the amount of emitted light (90% in front and 10% in both sides) are the same as in the first embodiment. It was. In the third embodiment, the diameter of the phosphor layer 107 can be freely adjusted by the dam 109. In the test process, the diameters of the phosphor layer 107 were "1.4 mm", "1.6 mm", "1.8 mm", and "2.0 mm", respectively.

In the second embodiment, the blue band was found at the edge of the light source, but in the third embodiment, the yellow band and the blue band were completely removed. In other words, since the area of the phosphor layer 107 on the upper surface of the transparent glass 105 is equal to the angle at which the light source is emitted, yellow bands and blue bands are not generated.

However, since the dam 109 was treated with black ink, a slight light loss occurred as compared with the existing one.

(Example 4)

21 is a cross-sectional view illustrating a structure of a semiconductor package using a phosphor filter according to a fourth embodiment of the present invention.

The LED package of FIG. 21 includes a substrate 40 on which a cavity 46 is formed; An LED chip 42 mounted in a light emitting element mounting region in the cavity 46; A wire 44 for electrically connecting the LED chip 42 to a pattern electrode (not shown); And phosphor filters 50, 52, and 54 installed horizontally spaced apart from the LED chip 42 on the upper part of the LED chip 42.

In the fourth embodiment, the phosphor filter differs from the phosphor filter in the other embodiments.

The phosphor filter of the fourth embodiment is provided horizontally on the opening of the lower cavity 46b. The phosphor filter includes a transparent glass 50 of a flat plate having an accommodating groove 52 formed on an upper surface or a lower surface (upper surface in FIG. 21); And a phosphor layer 54 filled in the receiving groove 52. The length (or diameter) of the receiving groove 52 is smaller than the diameter of the lower cavity 46b. The storage groove 52 is called a charging part.

The transparent glass 50 has a light transmittance of a predetermined value or more (eg, 90% or more). The transparent glass 50 is AR coated to improve light transmittance. In addition, the transparent glass 50 is thermally strengthened.

In the phosphor layer 54, granular phosphor and silicon (or epoxy) are blended in a predetermined compounding ratio.

A predetermined medium (eg, air or silicon (or epoxy)) 48 is accommodated in the space between the LED chip 42 and the phosphor filter. The use of transparent silicon in the medium 48 is superior in light efficiency to air.

A diffusion layer 56 is further formed on the upper surface of the phosphor filter.

In the above description, the inner surface of the receiving groove 52 is preferably etched flat. When the size or diameter of the storage groove 52 (that is, the size or diameter of the phosphor layer 54) is less than the reference value, the blue band is more likely to occur when the phosphor layer 54 is formed and then used, When the size or diameter (that is, the size or diameter of the phosphor layer 54) becomes larger than the reference value, a yellow band is more likely to occur, so the diameter or size of the receiving groove 52 is preferably a numerical value obtained by experiment. Do. For example, assuming that the substrate size is 5.0 * 5.0mm, the size of the upper cavity is approximately 4.0 * 4.0mm, the size of the lower cavity is approximately 2.6 * 2.6mm, and the size of the transparent glass 50 is approximately 3.0 * 3.0mm. Assume At this time, when the directivity angle of the LED chip 42 is 120 degrees and the distance between the LED chip 42 and the phosphor layer 54 is approximately 2.8 mm ± 0.3 mm, the LED chip 42 is made of Cree. When the chip (about 80% of the light is emitted in the front and about 20% of the light is emitted in both sides), the diameter of the phosphor layer 54 is most preferably about 2.1 mm to remove the yellow band. In the above assumption, if the LED chip 42 is a semi-red chip (about 90% of the light is emitted from the front and about 10% of the light is emitted from both sides), the phosphor is removed to remove the yellow band. The diameter of layer 54 is most preferably about 2.2 mm.

The phosphor filter of the fourth embodiment has the advantage that the phosphor layer 54 is formed in the receiving groove 52 of the transparent glass 50, thereby reducing the thickness than the phosphor filter of the other embodiment.

When the semiconductor package is manufactured based on the numerical values exemplified above, the diameter of the receiving groove 52 is slightly smaller than the diameter of the opening of the lower cavity 46. About 10 to 20% of the light emitted from the LED chip 42 exits both sides of the accommodating groove 52 and exits through the transparent glass 50. In this case, the light passing through both sides of the accommodating groove 52 and passing through the transparent glass 50 is diffusely reflected until it passes through the transparent glass 50, and then mixed with the white light passing through the phosphor layer 54. Yellow band does not occur.

According to the configuration as shown in FIG. 21, the phosphor layer 54 is formed in a uniform thickness in the accommodating groove 52 of the transparent glass 50 of the flat plate installed horizontally on the top of the LED chip 42. This configuration simply solves the problem of the conventional horizontal mold. For this reason, since the light emitted from the LED chip 42 passes through the phosphor filter having a uniform thickness, color coordinate scattering is stabilized as compared with the conventional one, which makes a great contribution to the yield improvement. Since the length of the movement path of the light emitted from the LED chip 42 and passing through the phosphor filter, in particular the phosphor layer 54, is the same, yellow band generation is suppressed. Since the diffusion layer 56 is further formed on the phosphor filter, a fine yellow band may be completely removed by diffusion in the diffusion layer 56.

22 to 32 are views for explaining the configuration and manufacturing process of the phosphor filter and the semiconductor package using the phosphor filter according to the fourth embodiment of the present invention.

The jig (not shown) arranges the transparent glass 70 of the flat plate. At this time, the transparent glass 70 was AR-coated in advance to reduce the surface reflectance of the projected light and increase the transmittance thereof, and was thermally strengthened to prevent deformation during subsequent step curing.

The mask (not shown) of a predetermined pattern is printed on the upper surface of the transparent glass 70. Mask printing is to mark the part to be etched. For example, a mask is printed on the remaining portions except those to be etched. Thereafter, etching is performed at a predetermined depth on the remaining portions of the upper surface of the transparent glass 70 except for portions where the masks are arranged.

By etching, a plurality of receiving grooves 52 as shown in FIG. 22 are formed on the upper surface of the transparent glass 70. The receiving groove 52 has a plane such as a circle or the like. For example, if the thickness of the transparent glass 70 is approximately 300 µm, the depth of the receiving groove 52 by etching is approximately 100 µm ± 50 µm. Here, the numerical values of the thickness of the transparent glass 70 and the depth of the receiving groove 52 are adjusted by the thickness of the substrate 40 and the size and the orientation angle of the LED chip 42.

After dispensing the phosphor liquid 74 which is the primary degassed compound liquid phase (for example, silicon type or binder type), a top plate tool (not shown) equipped with a squeeze 72 is shown from left to right in FIG. 22. Move it. Then, as shown in FIG. 23, the phosphor layer 54 is formed flat in the accommodating groove 52 of the transparent glass 70. 24 is a plan view of the top of FIG. 23 viewed from above. Due to the mask, the height of the phosphor layer 54 may be larger than the depth of the accommodating groove 52. However, it is negligible because the thickness of the printed mask is very thin.

22 and 23 illustrate forming the phosphor layer 54 by a squeeze method, but a spin coating method may be employed. On the other hand, after a nozzle having a predetermined size of openings is vertically spaced apart from the top of the jig, a spray method of spraying the phosphor liquid 72 downward while moving the nozzle from left to right may be adopted. Of course, if the amount of phosphor to be doped can be adjusted, dotting method may be used.

Subsequently, step curing is performed after the secondary defoaming to remove the fine bubbles in the phosphor layer 54. Curing is carried out for approximately one hour at a temperature of approximately 60 ° C. and then for approximately three hours at a temperature of approximately 150 ° C. again. If step curing is performed instead of curing at a high temperature, desired physical properties of the phosphor layer 54 can be better expressed, and the phosphor layer 54 can be better adhered to the receiving groove 52.

For convenience, it may be advisable to remove the mask after step curing. The mask may be removed as soon as step cure finishes or may be removed after a subsequent sawing process.

After removing the mask after step curing, the transparent glass 70 as shown in FIG. 24 is mounted on the upper surface of a myler sheet (not shown) for the subsequent sawing process.

Subsequently, sawing is performed along the cutting line a indicated by the dotted line in FIG. 25. The cutting line a is not displayed on the transparent glass 70. The cutter (not shown) performs as if cutting along the cutting line a when sawing according to a programmed standard.

After finishing the sawing process, the mylar sheet (not shown) is expanded in all directions as shown in FIG. This is to make it easy to separate a plurality of phosphor filters on the mylar sheet from the mylar sheet. By this process, the phosphor filter of the fourth embodiment is manufactured.

Hereinafter, a process of manufacturing a semiconductor package using the phosphor filter of the fourth embodiment will be described.

After preparing the substrate 40 having the lower cavity 46b and the upper cavity 46a as shown in FIG. 27, the LED 44 is mounted on the light emitting device mounting area of the substrate 40 to bond the wires 44. . Here, the cavity of the substrate 40 has a plane as illustrated in the photograph of FIG. 28. The shape of the cavity shown in FIG. 28 is also applicable to the first to third embodiments described above. That is, the planar shape of the interface between the upper cavity 46a and the lower cavity 46b (that is, the surface in contact with the opening of the lower cavity) is a flower pattern. This is to form a vent through which bubbles can escape during subsequent secondary defoaming and step cure. Of course, the shape of the protrusion may be used instead of the shape of the plug. Then, primary dispensing is performed on the lower cavity 46b using silicon or epoxy. In FIG. 27, reference numeral 80 is a part of the device for dispensing medium 48. The medium 48 is filled in the lower cavity 46b by primary dispensing.

Then, the sawed and united phosphor filter as shown in FIG. 29 is placed flat on the opening of the lower cavity 46b. Steps (not shown) may be formed in advance in contact with the lower cavity 46b and the upper cavity 46a in order to facilitate installation and fixing of the phosphor filter. 29 is the same as the photograph of FIG. 30.

Thereafter, secondary defoaming and step curing are performed. This completes the desired semiconductor package.

Of course, the process of forming the diffusion layer 56 may be additionally performed. That is, after finishing the operation up to FIG. 29, secondary defoaming and step curing are performed, and secondary dispensing for forming the diffusion layer 56 is performed on the upper part of the phosphor filter as shown in FIG. 31, and step curing is performed. do. If necessary, transparent silicon may be molded or left in the air instead of the diffusion layer 56. 32 shows a planar state when the diffusion layer 56 is formed on the phosphor filter. In FIG. 32, the top portion becomes the diffusion layer 56 filled in the upper cavity 46a.

33 is a data sheet when the phosphor filter of the fourth embodiment is used, and FIG. 34 is a graph showing color coordinate data in the data sheet of FIG.

Looking at the graph based on the color coordinate data (chrom x, chrom y) on the data sheet of FIG. 33 (see FIG. 34), it can be seen that a product classified as an extraneous product is not generated due to the stability of the color coordinate distribution.

The deviation (0.033 (0.351-0.318) and 0.051 (0.382-0.331)) between the minimum value MIN and the maximum value MAX of each of the color coordinate data chrom x and chrom y on the data sheet of FIG. 33 is existing (FIG. 3A). It is extremely small compared to the deviation (0.053, 0.091) between the minimum value and the maximum value of each color coordinate data. This means that the color coordinate dispersion of the phosphor filter manufactured by the fourth embodiment is narrower (ie, the color coordinate dispersion is stable) than in the prior art, so that the incidence of the product to be treated as an external product is very low.

And when comparing the light efficiency on the data sheet of FIG. 33 and the light efficiency (conventional) on the data sheet of FIG. 3A, it can be seen that the light efficiency of the product of the present invention is significantly improved compared to the light efficiency of the existing product.

35 is a photograph illustrating whether yellow bands are generated after applying the phosphor filter of the fourth exemplary embodiment of the present invention. As can be seen from (a), (b), and (c) of FIG. 35, when a subject emits light emitted from a semiconductor package employing the phosphor filter of the fourth embodiment of the present invention, a yellow band is formed. It can be confirmed that it does not occur at all. In other words, since the area of the phosphor layer 54 on the upper surface of the transparent glass 50 is equal to the angle at which the light source is emitted, yellow and blue bands are not generated.

According to the first to fourth embodiments of the present invention described above, the yellow band can be removed even with a small amount of phosphor compared with the conventional method. Of course, there were some problems in the first to third embodiments, but the yellow band was basically removed. The fourth embodiment solves the conventional problems and solves all of the slight problems arising in the above embodiments (first to third embodiments).

FIG. 36 is a table showing differences in luminous flux between the configuration of FIG. 4, the configuration of the third embodiment of the present invention, and the configuration of the fourth embodiment. FIG. 36A compares the luminous flux (unit: lm) in the case of testing using the configuration of the existing (FIG. 4) and the luminous flux in the case of testing using the configuration of the third embodiment. Referring to (a) of FIG. 36, the configuration of the third embodiment is about 17% lower than that of the conventional configuration in the luminous flux, but the third embodiment is very large in that yellow bands (and blue bands) can be completely removed. It works. Of course, the first and second embodiments also have a great effect in that the yellow stripe can be completely removed. FIG. 36B compares the luminous flux (unit: lm) in the case of testing using the configuration of the third embodiment and the luminous flux in the case of testing using the configuration of the fourth embodiment. Referring to (b) of FIG. 36, it can be seen that the configuration of the fourth embodiment is about 20% superior to the configuration of the third embodiment in the luminous flux. FIG. 36C compares the luminous flux (unit: lm) in the case of testing using the configuration of the existing (FIG. 4) and the luminous flux in the case of testing using the configuration of the fourth embodiment. Referring to (c) of FIG. 36, it can be seen that the configuration of the fourth embodiment is about 0.07% superior to the conventional configuration in the luminous flux. This is very effective in that the fourth embodiment can completely remove the yellow band (and the blue band), and there is no loss in the light flux as compared with the conventional one, and is very stable in the color coordinate scattering.

On the other hand, the present invention is not limited only to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, the technical idea to which such modifications and variations are also applied to the claims Must see

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

2 is a view for explaining the problem of the 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.

Figure 4 is a cross-sectional view showing the configuration of another conventional LED package.

5 is a photograph for explaining a background of capturing a phenomenon in which a yellow band is removed.

6 and 7 are views for explaining the configuration of the phosphor filter and the semiconductor package using the same according to the first embodiment of the present invention.

8 is a photograph showing the results of testing the first embodiment of the present invention.

9 and 10 are views for explaining the configuration of the phosphor filter according to a second embodiment of the present invention.

11 is a photograph showing the results of testing the second embodiment of the present invention.

12 and 13 are views for explaining the configuration of the phosphor filter according to the third embodiment of the present invention.

14 to 20 are views for explaining a process of manufacturing a semiconductor package according to a third embodiment of the present invention.

21 is a cross-sectional view illustrating a semiconductor package using a phosphor filter according to a fourth exemplary embodiment of the present invention.

22 to 32 are views for explaining the configuration and manufacturing process of the phosphor filter and the semiconductor package using the phosphor filter according to the fourth embodiment of the present invention.

Fig. 33 is a data sheet when the phosphor filter of the fourth embodiment of the present invention is used.

FIG. 34 is a graph illustrating color coordinate data in the data sheet of FIG. 33.

35 is a photograph illustrating whether yellow bands are generated after applying the phosphor filter of the fourth exemplary embodiment of the present invention.

FIG. 36 is a table showing differences in luminous flux between the configuration of FIG. 4, the configuration of the third embodiment of the present invention, and the configuration of the fourth embodiment.

<Description of Symbols for Major Parts of Drawings>

40: substrate 42: LED chip

44: wire 46: cavity

48: medium 50: transparent glass

52: receiving groove 54: phosphor layer

Claims (16)

Preparing a phosphor filter by forming a phosphor layer having a smaller area than that of the transparent substrate on a transparent substrate of a flat plate; A second step of preparing a substrate including a cavity having an area larger than that of the phosphor layer; A third step of mounting a light emitting device on a bottom surface of the cavity; And And a fourth process of installing the phosphor filter on the cavity on which the light emitting element is mounted. The method according to claim 1, In the first step, a method of manufacturing a semiconductor package using a phosphor filter, characterized in that to form a dam on the transparent substrate and to fill the phosphor layer in the dam. The method according to claim 1, In the first step, a method of manufacturing a semiconductor package using a phosphor filter characterized in that the transparent substrate is etched to form a filling portion and the phosphor layer is filled in the filling portion. A semiconductor package comprising a cavity having a light emitting element mounting region, A light emitting device mounted on the light emitting device mounting area; And A phosphor filter having a transparent substrate on a plate and a phosphor layer formed on the transparent substrate and installed on the cavity; The area of the phosphor layer is smaller than the area of the cavity semiconductor package using a phosphor filter. The method according to claim 4 A dam is formed around the phosphor layer, and the phosphor layer is filled in the dam, the semiconductor package using a phosphor filter. The method according to claim 4, A charging unit is formed on one surface of the transparent substrate, and the phosphor layer is filled in the inside of the charging unit semiconductor package using a phosphor filter. The method according to claim 4, A medium is filled between the light emitting element and the phosphor filter, and a portion of the filled medium and the phosphor filter do not overlap each other. The method according to any one of claims 4 to 7, A semiconductor package using a phosphor filter, characterized in that the diffusion layer is further formed on the phosphor filter. delete A transparent substrate of a flat plate spaced apart from the top of the light emitting device; And And a phosphor layer formed on one surface of the transparent substrate and having a smaller area than the area of the transparent substrate. The method according to claim 10 The phosphor layer is surrounded by a dam. The method according to claim 10, The phosphor layer is filled with a charging portion formed concave on one surface of the transparent substrate. A first process of preparing a transparent substrate of the plate which is spaced apart from the upper portion of the light emitting device; And And a second process of forming a phosphor layer on one surface of the transparent substrate having a smaller area than the area of the transparent substrate. The method according to claim 13, In the second process, a method of manufacturing a phosphor filter, characterized in that a dam is formed on one surface of the transparent substrate and the phosphor layer is filled in the dam. The method according to claim 13, In the second process, the filling portion is formed on one surface of the transparent substrate and the method of manufacturing a phosphor filter, characterized in that to fill the phosphor layer inside the filling portion. The method according to claim 13, The second process is a method of manufacturing a phosphor filter, characterized in that the filling by using any one of the squeeze method, spin coating method, dotting method and spray method.

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