JP2002252376A - Surface mount type light emitting diode and method of manufacturing the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To ensure the reliability of a metal wire connection portion of an LED chip, to make uniform the emission wavelength of the LED, and to radiate light from the upper surface of the LED chip to the side surface. Provided are a surface-mounted LED capable of reducing unevenness in color tone with light emitted from the LED, and a method for manufacturing the same. SOLUTION: An LED chip 3 arranged on a substrate 1;
A chip sealing portion 5a for sealing the LED chip 3, and a chip sealing portion provided around the chip sealing portion 5a with a height higher than the height of the chip sealing portion 5a via a groove 5b. A first light-transmitting resin layer 5 having an enclosing portion 5c and a second light-transmitting resin layer 6 containing a fluorescent agent and formed inside the chip sealing portion enclosing portion 5c are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a surface mount type light emitting diode and a method of manufacturing the same.

[0002]

2. Description of the Related Art Light emitting diodes (hereinafter, referred to as light emitting devices).
LEDs) are small in size, can emit light of a bright color with good efficiency, have excellent driving characteristics, and are resistant to vibration and repeated ON / OFF lighting. Therefore, it is used as various indicators and various light sources.

In manufacturing a conventional surface mount type LED, first, an LED chip is mounted on a substrate such as a glass epoxy resin using a silver paste or the like, and an electrode provided on the LED chip and an electrode provided on the substrate are connected. Connect with a metal wire such as a gold wire. Next, an epoxy resin dispersion medium mixed with a fluorescent agent for converting the wavelength of light emitted from the LED chip is dipped or the like, and cured to seal the LED chip, thereby forming a chip sealing layer. After that, a mold having a plurality of recesses larger than the chip sealing layer provided at predetermined intervals is set with each chip sealing layer placed in each recess, and epoxy resin is set in a space between each recess and the substrate. Is injected and cured to form a sealing lens layer covering the chip sealing layer.

[0004]

However, in the above-mentioned conventional method of manufacturing a surface mount type LED, when forming a chip sealing layer, an epoxy resin dispersion medium in which a fluorescent agent is dispersed is pre-dip or the like. Since a step of dropping a predetermined amount for each LED chip is required, there is a problem that the manufacturing process is complicated. In addition, since the fluorescent agent directly covers the LED chip surface, there is a problem that the fluorescent agent comes into contact with a portion where reliability is required, such as a gold wire connection portion of the LED chip, and the reliability is impaired. Then, during mass production, the shape of the chip sealing layer of each LED could not be made uniform, and the content of the fluorescent agent in each chip sealing layer could not be controlled. Further, since the thickness of each chip sealing layer cannot be made uniform and the distribution of the fluorescent agent is not uniform, there is a problem that a difference occurs in the wavelength conversion efficiency and the color tone of the LED is uneven.

[0005] Further, after the LED chip is sealed with a translucent resin containing no fluorescent agent to form a chip sealing layer,
Some LEDs have the upper surface of the chip sealing layer covered with a sheet-like translucent resin mixed with a fluorescent agent. In this case, the light emitted from the LED chip from the upper surface of the chip sealing layer and the light emitted from the side surface In this case, there is a problem that the color tone becomes uneven.

The present invention has been made in view of the above circumstances, and has a chip sealing portion provided corresponding to an LED chip, and a height around the chip sealing portion. A first light-transmitting resin layer having a chip sealing portion surrounding portion provided at a height higher than the height of the first light-transmitting resin layer, and a second light-transmitting resin layer formed inside the chip sealing portion surrounding portion. By
It is possible to ensure the reliability of the metal wire connection portion of the LED chip and the like, and to make the thickness of the second translucent resin layer containing the fluorescent agent uniform, thereby making the emission wavelength of the LED uniform. It is an object of the present invention to provide a surface-mounted LED that can reduce color tone unevenness between light emitted from the upper surface of a chip and light emitted from a side surface.

Further, according to the present invention, a mold having a plurality of convex portions having a concave portion corresponding to a chip sealing portion at a central portion provided at predetermined intervals is arranged on a substrate, and a transparent resin is poured. By forming the first light-transmitting resin layer in the first light-transmitting resin layer and forming the second light-transmitting resin layer in the recess of the first light-transmitting resin layer formed by the convex portion, the manufacturing process is simplified, As the mass productivity increases, the thickness of the second light-transmitting resin layer containing the fluorescent agent can be easily made uniform, and the color tone of the light emitted from the upper surface of the LED chip and the color tone of the light emitted from the side surface can be reduced. It is an object of the present invention to provide a method for manufacturing a surface-mounted LED that can be made uniform.

[0008]

According to a first aspect of the present invention, there is provided a surface mount type light emitting diode, a light emitting diode chip disposed on a substrate, a chip sealing portion for sealing the light emitting diode chip, and the chip sealing portion. A first translucent resin layer having a chip sealing portion surrounding portion provided at a height higher than the height of the chip sealing portion, and a fluorescent agent, A second translucent resin layer formed inside the surrounding portion.

In the first invention, since the first light-transmitting resin layer does not contain a fluorescent agent, the reliability of the metal wire connection portion of the LED chip can be ensured. Then, since the second translucent resin mixed with the fluorescent agent is formed inside the surrounding portion of the chip sealing portion, the second translucent resin is formed depending on the shape of the first translucent resin layer.
The shape of the translucent resin layer is determined. Therefore, the thickness of the second translucent resin layer can be made uniform, and the distribution of the fluorescent agent becomes uniform, so that the wavelength conversion efficiency becomes uniform and the emission wavelength of the LED becomes uniform. Then, not only above the LED chip but also the sides are covered with the second translucent resin layer,
The color tone unevenness between the light emitted from the upper surface and the light emitted from the side surface of the LED chip is reduced.

According to a second aspect of the present invention, there is provided a method of manufacturing a surface mount type light emitting diode, comprising the steps of: mounting a light emitting diode chip on a substrate; and connecting an electrode provided on the substrate and an electrode provided on the light emitting diode chip to a metal wire. And a step of sealing the light emitting diode chip with a translucent resin to form a chip sealing portion, and a step of covering the chip sealing portion with a translucent resin containing a fluorescent agent. In the method for manufacturing a surface mount type light emitting diode, a mold in which a plurality of convex portions having a concave portion corresponding to the chip sealing portion in the center portion are provided at predetermined intervals, and each concave portion is opposed to each light emitting diode chip. In this state, a step of disposing a predetermined distance above the substrate, a step of pouring a translucent resin between the mold and the substrate, and curing the translucent resin, Open 1) a step of forming a light-transmitting resin layer, a step of injecting a light-transmitting resin containing a fluorescent agent into a recess of the first light-transmitting resin layer formed by the convex portion, And forming a second light-transmitting resin layer by curing the resin.

In the second invention, a first translucent resin layer is formed by pouring a translucent resin between the mold and the substrate, and the first translucent resin layer includes a fluorescent agent in a recess. Since the second translucent resin layer is formed by injecting the translucent resin, the manufacturing process is simplified and the mass productivity is improved. Further, since the second light-transmitting resin layer is formed in the depression of the first light-transmitting resin layer, the shape of the second light-transmitting resin layer of each LED becomes the same based on the depression, and each second light-transmitting resin layer becomes the same. The content of the fluorescent agent in the conductive resin layer is made uniform. Further, also in each of the second light-transmitting resin layers, the thickness is easily made uniform based on the recess, the distribution of the fluorescent agent is made uniform, and the emission wavelength of the LED is made uniform. The shape of the recess is such that the second translucent resin layer can sufficiently cover the side surface of the LED chip, so that the color tone of the light emitted from the upper surface of the LED chip and the color tone of the light emitted from the side surface of the LED chip. And can be made uniform. Therefore, by the method for manufacturing a surface-mounted light-emitting diode according to the second invention, a surface-mounted light-emitting diode having improved quality and performance can be obtained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments. FIG. 1 is a plan view showing the structure of a surface-mounted LED according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II. In the figure,
1 is a substrate. Substrate 1 made of glass epoxy resin, etc.
Are connected to external electrodes 2 and 2 for connection to an external circuit.
Is provided. A chip mounting portion 2a is provided at the center of one of the external electrodes 2 so as to protrude toward the center of the substrate 1, and an LED chip 3 having a GaN-based compound semiconductor as a light emitting layer is mounted at an end thereof. Have been. On the other external electrode 2, an internal electrode 2b is provided so as to face the chip mounting portion 2a. One electrode of the LED chip 3 is connected to the chip mounting portion 2 a by a gold wire 4, and the other electrode is connected to the internal electrode 2 b by a gold wire 4.

The LED chip 3 is sealed with a first light transmitting resin layer 5 made of a light transmitting resin such as an epoxy resin. The first translucent resin layer 5 has a height around the chip sealing portion 5a via the chip sealing portion 5a for directly sealing the LED chip 3 and the groove portion 5b, and the height of the chip sealing portion 5a. And a chip sealing portion surrounding portion 5c provided at a height higher than the height.

[0014] Inside the chip enclosing portion surrounding portion 5c,
In portions corresponding to the upper side and the side of the chip sealing portion 5a,
A second light-transmitting resin layer 6 made of a light-transmitting resin layer such as an epoxy resin containing a fluorescent agent is formed. The fluorescent agent is LED
A fluorescent substance such as a fluorescent paint, a fluorescent pigment, or a fluorescent substance, which can convert the emission wavelength of the chip 3 to another wavelength.

In the surface mount type LED of the present invention, since the first translucent resin layer 5 does not contain a fluorescent agent,
The reliability of the portion of the chip 3 where the gold wire 4 is connected can be ensured. Then, the second translucent resin 6 mixed with the fluorescent agent is formed inside the chip sealing portion surrounding portion 5c, so that the first
The shape of the second light-transmitting resin layer 6 is determined by the shape of the light-transmitting resin layer 5. Therefore, the thickness of the second translucent resin layer 6 can be made uniform, and the distribution of the fluorescent agent becomes uniform, so that the wavelength conversion efficiency becomes uniform and the emission wavelength of the LED becomes uniform. Further, since not only the upper side but also the side of the LED chip 3 is covered with the second translucent resin layer 6, the color tone unevenness of the radiated light from the upper surface and the radiated light from the side surface of the LED chip 3 is reduced. I do.

Hereinafter, a method of manufacturing a surface-mounted LED according to the present invention will be described. After a plurality of the surface mount LEDs of the present invention are manufactured on a substrate, they are individually separated by cutting. Electrodes 2 and 2 are provided at both ends of the substrate 1 so that the extending direction thereof coincides with the longitudinal direction of the substrate 1. One electrode 2 is provided at predetermined intervals with chip mounting portions 2 a and 2.
are provided on the other electrode 2 with internal electrodes 2b, 2b,... facing the chip mounting portions 2a, 2a,. Each of the chip mounting portions 2a, 2a,.
3 are mounted with silver paste or the like, one electrode of each LED chip 3 is a chip mounting portion 2a, and the other electrode is an internal electrode 2
b and gold wires 4 and 4, respectively.

FIG. 3 is a cross-sectional view of the substrate 1 in the direction in which the electrodes 2 extend, and is a cross-sectional view illustrating the following manufacturing process.
First, a metal or epoxy resin mold 7 in which a plurality of convex portions 7b having a concave portion 7a corresponding to the chip sealing portion 5a at a central portion are provided at predetermined intervals, and each concave portion 7a is
In a state of facing the D chip 3, it is arranged above the substrate 1 at a predetermined interval (FIG. 3A).

Next, a light-transmitting resin is poured between the mold 7 and the substrate 1, the light-transmitting resin is cured, and the mold 7 is opened to form the first light-transmitting resin layer 5 (FIG. 3). (B)). And
A translucent resin containing a fluorescent agent is injected into the recess of the first translucent resin layer 5 formed by the protruding portion 7b, and the translucent resin is cured to form the second translucent resin layer 6. Form. Thereafter, the wafer is cut into a predetermined width to obtain individually separated surface-mounted LEDs (FIG. 3C). When the light emitting layer of the LED chip 3 is a GaN-based compound semiconductor and emits blue light, the fluorescent agent may be cadmium zinc sulfide activated by copper or yttrium aluminum activated by cerium.
A phosphor that absorbs blue light and emits yellow light, such as a garnet-based phosphor, may be used. Due to this color mixture, the surface-mounted LED emits white light.

As described above, the surface mount type LED of the present invention
In the manufacturing method of (1), a first light-transmitting resin layer 5 is formed by pouring a light-transmitting resin between the mold 7 and the substrate 1.
Since the second light-transmitting resin layer 6 is formed by injecting a light-transmitting resin containing a fluorescent agent into the recess of the light-transmitting resin layer 5, the manufacturing process is simplified. Then, the shape of the second translucent resin layer 6 of each LED becomes the same due to the recess, the content of the fluorescent agent of each LED can be made uniform, and mass productivity is improved. Further, since the second light-transmitting resin layer 6 is formed in the depression of the first light-transmitting resin layer 5, the thickness of the second light-transmitting resin layer 6 can be easily made uniform based on the depression, By making the distribution of the fluorescent agent uniform, the emission wavelength of the LED can be made uniform. Furthermore, by making the shape of the recesses such that the second translucent resin layer 6 can sufficiently cover the side surface of the LED chip 3, the light emitted from the upper surface of the LED chip 3 and the light emitted from the side surface are reduced. Can be reduced.

In the above embodiment, GaN
The case where the LED chip 3 of the system is used has been described, but the present invention is not limited to this.
LED chips 3 that emit light of other colors, such as GaAs, GaAs, GaAlAs, and ZnO, may be used. In this case, a fluorescent agent is selected according to the emission color of the LED chips 3.

[0021]

As described above in detail, in the case of the first invention, since the first translucent resin layer does not contain a fluorescent agent, the reliability of the metal wire connection portion of the LED chip is ensured. be able to. Then, since the second translucent resin mixed with the fluorescent agent is formed inside the surrounding portion of the chip sealing portion, the first translucent resin is formed.
The shape of the second light-transmitting resin layer is determined by the shape of the light-transmitting resin layer. Therefore, the thickness of the second translucent resin layer can be made uniform, and the distribution of the fluorescent agent becomes uniform, so that the wavelength conversion efficiency becomes uniform and the emission wavelength of the LED becomes uniform. Since not only the upper side but also the side of the LED chip is covered with the second translucent resin layer, the color tone unevenness of the light emitted from the upper surface and the light emitted from the side surface of the LED chip is reduced.

In the case of the second invention, a light-transmitting resin is poured between the mold and the substrate to form a first light-transmitting resin layer, and a fluorescent agent is filled in the recess of the first light-transmitting resin layer. Since the second translucent resin layer is formed by injecting the translucent resin containing, the manufacturing process is simplified, the content of the fluorescent agent is easily controlled, and mass productivity is improved. Further, since the second light-transmitting resin layer is formed in the depression of the first light-transmitting resin layer, the shape of the second light-transmitting resin layer of each LED becomes the same based on the depression, and each second light-transmitting resin layer becomes the same. The content of the fluorescent agent in the conductive resin layer becomes uniform. Further, since the thickness of each of the second translucent resin layers is also easily made uniform, the distribution of the fluorescent agent is made uniform, and the emission wavelength of the LED is made uniform. Then, the shape of the recess is changed to the second shape.
By forming the transparent resin layer into a shape that can sufficiently cover the side surface of the LED chip, it is possible to reduce color tone unevenness between light emitted from the upper surface of the LED chip and light emitted from the side surface. Therefore, a surface-mounted LED with improved quality and performance can be obtained by the method of the second invention.

[Brief description of the drawings]

FIG. 1 is a plan view showing a structure of a surface mount LED according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a cross-sectional view illustrating a manufacturing process of the surface-mounted LED according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Electrode 3 LED chip 4 Gold wire 5 First translucent resin layer 5a Chip sealing part 5b Groove part 5c Chip sealing part surrounding part 6 Second translucent resin layer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4M109 AA02 BA04 CA21 DB15 GA01 5F041 AA11 AA14 AA42 AA43 CA35 DA07 DA12 DA17 DA43 DA56 DA58 DA62 DA92 5F061 AA02 BA04 CA21 FA01

Claims (2)

[Claims] 1. A light emitting diode chip disposed on a substrate, a chip sealing portion for sealing the light emitting diode chip, and a height around the chip sealing portion, the height of the chip sealing portion. A first light-transmitting resin layer having a chip sealing portion surrounding portion provided at a height higher than a height, and a second light-transmitting resin layer containing a fluorescent agent and formed inside the chip sealing portion surrounding portion. A surface-mounted light-emitting diode comprising: 2. A step of mounting a light-emitting diode chip on a substrate, a step of connecting an electrode provided on the substrate to an electrode provided on the light-emitting diode chip by a metal wire, and A step of forming a chip sealing portion by sealing with a light resin, and a step of covering the chip sealing portion with a light-transmitting resin containing a fluorescent agent; A mold provided with a plurality of convex portions having a concave portion corresponding to the sealing portion at the center at a predetermined interval is provided at a predetermined interval above the substrate with each concave portion facing each light emitting diode chip. Forming a first light-transmitting resin layer by curing the light-transmitting resin, opening the mold, and forming a first light-transmitting resin layer. A process and the convex portion A step of injecting a translucent resin containing a fluorescent agent into the recess of the first translucent resin layer thus formed; and a step of curing the translucent resin to form a second translucent resin layer. A method for manufacturing a surface-mounted light emitting diode, comprising: