KR101090991B1

KR101090991B1 - LED package and method of manufacturing the LED package

Info

Publication number: KR101090991B1
Application number: KR1020100031688A
Authority: KR
Inventors: 박종원; 이명렬
Original assignee: (주) 아모엘이디
Priority date: 2010-04-07
Filing date: 2010-04-07
Publication date: 2011-12-08
Also published as: KR20110112539A

Abstract

An LED package and a method of manufacturing the same are provided to reduce the deviation of the orientation angle. The LED package is provided with a cavity having a light emitting device mounting area, and the cavity is formed of a substrate including a reflecting plate seating surface and an adhesive surface in contact with the reflecting plate seating surface, and is formed separately from the substrate and seated on the reflecting plate mounting surface, The opposite surface includes a reflecting plate formed to be spaced apart from the adhesive surface. The reflective plate seating surface and the stepped adhesive surface make the positioning of the reflective plate very easy. This not only improves the precision for reflector placement but also reduces manufacturing tolerances. Conventionally, the deviation of the orientation angle was about ± 15 degrees, but according to the above-described embodiment of the present invention, the angle may be reduced to about ± 5 degrees. In addition, the adhesive surface of the upper portion of the adhesive surface serves to prevent the adhesive from leaking out to help the bonding between the substrate and the reflector. It is possible not only to implement a narrow angle of view without using a lens, but also to reduce the angle of deviation.

Description

LED package and method of manufacturing the same {LED package and method of manufacturing the LED package}

The present invention relates to an LED package and a method for manufacturing the same, and more particularly, to an LED package and a method for manufacturing the same used for lighting.

Light emitting diodes (hereinafter, referred to as LEDs) are semiconductor devices capable of realizing various colors. The LED constitutes a light emitting source by changing compound semiconductor materials such as GaAs, AlGaAs, GaN, InGaN, and AlGaInP. At present, many such semiconductor devices have been adopted in the form of packages in electronic components.

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 FIGS. 1 and 2.

The LED package illustrated in FIGS. 1 and 2 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 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; A reflector 22 formed along the inner surface of the cavity of the second substrate 20 to surround the LED chip 14; 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 FIG. 2, the inclination angle θ of the cavity which becomes the inclination angle of the reflecting plate 22 is about 30 degrees based on the reference line (that is, the line perpendicular to the upper surface of the first substrate 10). In FIG. 1, the inclination angle θ of the reflecting plate 22 is 0 degrees. 1 and 2, the top surface of the phosphor layer 18 in contact with the outside becomes the light emitting area. The phosphor layer 18 typically consists of a mixture of phosphor and silicon. Since the phosphor scatters light, the inclination angle θ of the reflecting plate 22 does not affect the orientation angle.

1 and 2 differ in the inclination angle θ of the reflecting plate 22, but since the light emitting area is almost the same, the orientation angle is the same regardless of the inclination angle θ of the reflecting plate 22. That is, the directing angle by the LED package of FIGS. 1 and 2 is fixed at about 120 degrees to about 130 degrees.

Thus, a hemispherical lens usually made of silicone or epoxy is employed to escape the fixed orientation angle. 3 and 4 show a typical LED package employing a lens. 3 is further provided with a lens 25 in the configuration of FIG. 4 is further provided with a lens 25 in the configuration of FIG. When the lens 25 is used, the orientation angle can be adjusted to about 60 to 90 degrees.

In order to install the lens 25 on the front surface of the LED package (that is, the upper surface of the phosphor layer 18), an adhesive such as UV adhesive (ultraviolet curing adhesive), instant adhesive, or the like is used. An adhesive is not applied to a portion of the bottom surface of the lens 25 that contacts the top surface of the phosphor layer 18. This is because if the lens 25 is adhered to the front surface of the LED package after applying the adhesive to the contacting portion, light loss occurs later. Therefore, the adhesive is applied only to the portion of the bottom surface of the lens 25 that does not contact the top surface of the phosphor layer 18, and then adheres to the entire surface of the LED package.

In such an adhesive method, since the contact area is narrow, the adhesion is often inadequate, whereby the lens 25 is easily detached from the package main body after the adhesion. Even if the lens 25 is properly adhered, the thermal stress is generated when the LED chip 14 operates because the difference between the coefficient of thermal expansion between the lens 25 and the substrate is large. Thermal stress causes strain at the joints, resulting in interfacial separation.

In particular, when using a high-power LED chip, the interface separation phenomenon due to thermal stress is a big problem. In addition, the cost of manufacturing the lens 25 in the structure of Figures 3 and 4 is also expensive.

Accordingly, the LED package as shown in Fig. 5 was proposed, which narrowed the orientation angle without using a lens.

The LED package of FIG. 5 has an integrated substrate 30 made of, for example, a ceramic material. The cavity 32 is formed in the center portion of the substrate 30. The inner surface of the cavity 32 is plated to serve as a reflector (reflector) 34.

In the case of Figure 5, since the substrate 30 is made of a ceramic integrally, it takes a long time to process the ceramic. In the process of ceramic processing, the deviation of the orientation angle becomes wide due to the roughness of the ceramic working surface, the roughness of the Ag thru surface, the nonuniformity of plating, and the like.

In addition, the shape of the reflecting plate (reflector) is limited in the shape of the reflecting plate due to the reason that the circle is the easiest and the difficulty of the rectangle is high.

The present invention has been proposed to solve the above-mentioned conventional problems, and an object thereof is to provide an LED package and a method of manufacturing the same, which can reduce the deviation of the orientation angle.

In order to achieve the above object, the LED package according to a preferred embodiment of the present invention, a cavity having a light emitting device mounting area is formed, the cavity is a substrate including a reflective plate mounting surface and the adhesive surface in contact with the reflecting plate mounting surface; And a reflector formed separately from the substrate and seated on the reflecting plate seating surface, the reflecting plate being spaced apart from the bonding surface opposite to the bonding surface.

The substrate and the reflector are mutually joined by an adhesive filled in the space between the reflector and the adhesive surface.

The adhesive face is formed stepwise in the direction perpendicular to the reflecting plate seating face.

The adhesive face is formed obliquely with respect to the reflecting plate seating face.

The reflecting plate seating surface is formed above the light emitting element mounting region.

According to a preferred embodiment of the present invention, there is provided a method of manufacturing an LED package, comprising: preparing a substrate having a light emitting device mounting area and having a cavity including a reflective plate seating surface and an adhesive surface in contact with the reflective plate seating surface; Preparing a reflector; Mounting the reflector on the reflecting plate seating surface, the surface opposite to the bonding surface being spaced apart from the bonding surface; And bonding the substrate and the reflector to each other by filling an adhesive in the space between the reflector and the adhesive surface.

According to the present invention having such a configuration, the reflective plate mounting surface and the stepped adhesive surface make the positioning of the reflective plate very easy. This not only improves the precision for reflector placement but also reduces manufacturing tolerances. Conventionally, the deviation of the orientation angle was about ± 15 degrees, but according to the above-described embodiment of the present invention, the angle may be reduced to about ± 5 degrees.

In addition, the adhesive surface of the upper portion of the adhesive surface serves to prevent the adhesive from leaking out to help the bonding between the substrate and the reflecting plate.

It is possible not only to implement a narrow angle of view without using a lens, but also to reduce the angle of deviation.

It is easy to change the shape of the reflector to realize various light distribution patterns.

1 and 2 are cross-sectional views showing the configuration of a typical LED package.
3 and 4 are cross-sectional views showing the configuration of a general LED package employing a lens.
5 is a cross-sectional view showing the configuration of a general LED package narrowed the directivity angle.
Figure 6 is an exploded perspective view for explaining the configuration of the LED package and its manufacturing method according to an embodiment of the present invention.
7 is a state diagram of FIG.
8 is a perspective view of the LED package according to an embodiment of the present invention.
9 is a cross-sectional view showing a modification of the embodiment of the present invention.
10 is a perspective view of a modification of the embodiment of the present invention.

Hereinafter, an LED package and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the accompanying drawings. Prior to the detailed description of the present invention, the terms or words used in the specification and claims described below should not be construed as being limited to the ordinary or dictionary meanings. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

The LED package of the present invention to be described below may be applied to all SMD type packages such as ceramic packages, plastic packages, lead frame type packages, plastic + lead frame type packages.

Figure 6 is an exploded perspective view for explaining the configuration of the LED package and its manufacturing method according to an embodiment of the present invention. 7 is a state diagram of FIG. 8 is a perspective view of the LED package according to an embodiment of the present invention.

The LED package according to the embodiment of the present invention includes a substrate 40, a light emitting device 44, and a reflecting plate 46.

The substrate 40 may be any type as long as the light emitting element 44 can be mounted at a high density. As the material of the substrate 40, for example, alumina, quartz, calcium zirconate, forsterite, SiC, graphite, fusedsilica, mullite Cordierite, zirconia, beryllia, and aluminum nitride, low temperature co-fired ceramic (LTCC), high temperature co-fired ceramic (HTCC), plastics, metals, Varistors and the like. In the embodiment of the present invention, it is assumed that the substrate 40 is an LTCC substrate. The cavity 42 is formed in the substrate 40. The cavity 42 may be cylindrical or square shape. As needed, the shape of the cavity 42 may be a shape different from the shape mentioned above. The bottom surface of the cavity 42 becomes a light emitting element mounting region. The reflective plate mounting surface 40a and the adhesive surface 40b in contact with the reflective plate mounting surface 40a are formed at a position higher than the light emitting element mounting region. In FIG. 6, the adhesive surface 40b is formed stepped in a step shape. When the reflecting plate 46 is seated on the reflecting plate seating surface 40a, the reflecting plate 46 has a slight separation space between the reflecting plate 46 and the bonding surface 40b. In Fig. 6, the adhesive surface 40b is stepped stepwise so that two opposing surfaces with the reflecting plate 46 are provided. Of the two opposing faces, the lower opposing face may be in close contact with the opposing portion of the reflecting plate 46. The upper adhesive surface of the adhesive surface 40b serves to prevent the adhesive 48 from leaking out. The adhesive 48 is filled (coated) through the separation space. The adhesive agent 48 couples the substrate 40 and the reflector plate 46 to each other. Here, the adhesive 48 has heat resistance and high transmittance to light. In particular, the adhesive 48 may be made of silicone or epoxy used as a sealing material. On the other hand, the adhesive 48 may be a material that withstands temperature and other thermal shock when soldering the finished package. The adhesive agent 48 can also be called sealing material.

The light emitting element 44 is mounted in the light emitting element mounting region of the cavity 42. The light emitting element 44 is bonded through the wire 50.

The reflecting plate 46 is formed separately from the substrate 40. The reflecting plate 46 is made of ceramic or metal. The reflector 46 is seated on the reflector seating surface 40a. As for the reflecting plate 46, the surface opposing the adhesion surface 40b is spaced apart from the adhesion surface 40b by a predetermined distance. Here, the reflective plate 46 may be formed in various ways, such as a circle, a square, an ellipse. The shape of the reflecting plate 46 is preferably the same as the shape of the cavity 42.

Although not shown in FIGS. 6 to 8, a phosphor layer (eg, phosphor + silicon or epoxy) is filled around and on the light emitting device 44. In other words, referring to FIG. 7, it may be understood that the phosphor layer is filled from the bottom of the cavity 42 to the height of the reflector seating surface 40a.

Next, the manufacturing process of the LED package according to an embodiment of the present invention will be described.

First, the substrate 40 and the reflector plate 46 required in the embodiment of the present invention are prepared, respectively. The substrate 40 has a cavity 42. The cavity 42 has a light emitting element mounting area, and includes a reflecting plate seating surface 40a and an adhesive surface 40b in contact with the reflecting plate seating surface 40a. The reflector 46 is preferably made of the same material as the substrate 40. The reflecting plate 46 is formed with an inclined surface for reflection inward. The inclined surface is preferably silver plated to increase the reflectance.

When the substrate 40 and the reflecting plate 46 are prepared as described above, the light emitting device 44 is mounted on the bottom surface of the cavity 42 of the substrate 40 and the wire 50 is bonded.

A phosphor layer (not shown) is formed in the cavity of the substrate 40. In other words, the phosphor layer is filled from the bottom of the cavity 42 to the height from the reflecting plate seating surface 40a. Of course, the phosphor layer may be formed after the substrate 40 and the reflecting plate 46 are bonded to each other. Meanwhile, a heat treatment process for the substrate 40 on which the light emitting element 44 is mounted and the phosphor layer is formed, the reflector plate 46, and the like may be fully understood by those of ordinary skill in the art even if there is no separate explanation. .

Thereafter, the reflector 46 is seated on the reflector seating surface 40a of the cavity 42. Here, the outer width of the reflecting plate 46 is equal to or slightly less than the outer width of the reflecting plate seating surface 40a. It is preferable that the outer width of the reflecting plate 46 is slightly smaller than the outer width of the reflecting plate seating surface 40a. This is because the reflector 46 is more easily seated on the reflector seating surface 40a and the alignment is easily performed.

In this way, some space | interval space is formed between the reflecting plate 46 and the adhesive surface 40b of the cavity 42.

The adhesive 48 is filled (coated) in the separation space. Here, the adhesive 48 may be filled not only in the space between the opposing surface 40b and the reflecting plate 46, but also in the space between the opposing surface 40b and the reflecting plate 46. will be. Of course, depending on the situation, the adhesive 48 will penetrate to some extent between the reflecting plate seating surface 40a and the bottom of the reflecting plate 46. As a result, the substrate 40 and the reflector plate 46 are completely combined after drying.

The manufacturing process described above has described the process of manufacturing one LED package. Typically, a large number of LED package sets are manufactured in one production line, so that they may be cut later and singulated.

According to this embodiment of the present invention, the reflective plate mounting surface and the stepped adhesion surface is made easy to position the reflective plate very easily. This not only improves the precision for reflector placement but also reduces manufacturing tolerances.

It is possible not only to implement a narrow angle of view without using a lens, but also to reduce the angle of deviation. Conventionally, the deviation of the orientation angle was about ± 15 degrees, but according to the above-described embodiment of the present invention, the angle may be reduced to about ± 5 degrees.

Of course, it can be considered that there is only the reflecting plate seating surface 40a without forming the stepped adhesion surface 40b as in the above-described embodiment. However, in this case, only the bottom surface of the reflecting plate 46 is adhered to the reflecting plate seating surface 40a, so that the adhesive leaks out and the problem that the reflecting plate 46 is not easily placed in place occurs. Therefore, the embodiment of the present invention described above is a very useful invention that can solve these problems.

9 is a cross-sectional view showing a modification of the embodiment of the present invention. 10 is a perspective view of a modification of the embodiment of the present invention.

The modification differs in the shape of the adhesive surface compared with the embodiment of the present invention described above. In the above-described embodiment of the present invention, the adhesive surface is stepped stepwise, but in the modified example, the difference is that the adhesive surface 60b is formed obliquely with respect to the reflecting plate seating surface 60a.

9 and 10, reference numeral 60 denotes a substrate and 62 denotes a cavity.

Even with the modified example, the same effects as in the above-described embodiment of the present invention can be sufficiently obtained.

On the other hand, the present invention is not limited only to the above-described embodiments and can be carried out by modifications and variations within the scope not departing from the gist of the present invention, the technical idea that such modifications and variations are also within the scope of the claims Must see

40, 60: substrate 42, 62: cavity
44: light emitting element 46: reflecting plate
48: adhesive 50: wire

Claims

A cavity having a light emitting device mounting area is formed, the cavity including a substrate including a reflecting plate seating surface and an adhesive surface in contact with the reflecting plate seating surface; And
And a reflector formed separately from the substrate, the reflector being seated on the reflecting plate seating surface, the reflecting plate being spaced apart from the attaching surface opposite to the attaching surface.
The substrate and the reflecting plate are mutually coupled by an adhesive filled in the space between the reflecting plate and the adhesive surface,
The adhesive surface is formed stepped stepwise, and has an upper facing surface and a lower facing surface facing the reflecting plate,
The distance from the upper facing surface to the reflecting plate is formed farther than the distance from the lower facing surface to the reflecting plate, the LED package, characterized in that the reflecting plate extends higher than the upper facing surface.

delete

The method according to claim 1,
The reflector plate mounting surface LED package, characterized in that formed on the upper side than the light emitting device mounting area.

Preparing a substrate having a light emitting device mounting area and having a cavity including a reflective plate seating surface and an adhesive surface in contact with the reflective plate seating surface;
Preparing a reflector;
Mounting the reflective plate on the reflective plate seating surface, wherein the surface opposite to the adhesive surface is spaced apart from the adhesive surface; And
And bonding the substrate and the reflector to each other by filling an adhesive in the space between the reflector and the adhesive surface.
The adhesive surface is formed stepped stepwise, and has an upper facing surface and a lower facing surface facing the reflecting plate,
The distance from the upper facing surface to the reflecting plate is formed farther than the distance from the lower facing surface to the reflecting plate, the reflecting plate is characterized in that extending to the upper than the upper facing surface manufacturing method of the LED package.

delete

The method of claim 6,
The reflector seating surface is a manufacturing method of the LED package, characterized in that formed on the upper side than the light emitting device mounting area.