JP2001094157A - Chip component type light emitting diode and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting diode with stable shape of light emitting face and good light shielding and reflecting characteristics, by mounting a mounting substrate, in parallel with a light guiding plate without turning the substrate on its side. SOLUTION: A semi-circular through-hole is formed on a side face of a second substrate 43 mounted on a first substrate 42. An LED chip 44 is mounted in the through-hole on a pattern 46 of the first substrate 42 and connected to an electrode 45b with an Au wire 47 via a pattern 48. The through-hole is filled with a light-transmitting resin 49, and a third substrate 50 is stuck on an upper face of the second substrate 43. By forming a structure of side light-emitting type, the mounting substrate can be mounted in parallel with the light guiding plate without turning the substrate on its side. The shape of the light irradiating face can be determined by the shape of the through-hole, so that the shape of the light casting face can be made stable. In addition, the inner face of the through-groove is formed in a metallic through hole structure, light shielding and reflecting characteristics can be improved, and light directivity can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip component type LED (light emitting diode) mainly used for a backlight of a liquid crystal display device in a portable information terminal or the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art FIGS. 10 to 16 show the structure of a conventional chip component type LED for a backlight light source. In FIG. 10, a chip component type LED 8 includes an LED chip 3 on a pattern 6 connected to one electrode 2 a on the substrate 1.
And electrically connected to the pattern 7 connected to the other electrode 2b by the Au wire 4. And the structure which sealed the periphery with the transparent or milky resin 5 by transfer molding is provided.

The above-mentioned chip component type LED 8 is used as a light source for a backlight of a liquid crystal display device as follows. That is, as shown in FIG. 11, a plurality of chip component type LEDs 8 are mounted in a row on
The light guide plate 10 is vertically mounted on the substrate 9 so that the rows of the chip component type LEDs 8 face the end face 10a of the substrate 9. Then, the light emitted from the top of the chip component type LED 8 as shown by the arrow A is taken in from the end face 10a of the light guide plate 10 to be used as a liquid crystal backlight light source.

[0004] Further, it is also used as shown in FIG. That is, the plurality of chip component type LEDs 8 are mounted side by side on the substrate 11 in a horizontal position. And the light guide plate 12
Are disposed so as to take in the light emitted from the chip component type LED 8 from the end face 12a, and are used as a backlight source for liquid crystal.

FIG. 13 is an external view of a chip component type LED different from FIG. In this chip component type LED 15, the portion for mounting the LED chip 16 is concave, and the metal pattern portion connected to one electrode 17a is provided.
(Not shown) is formed on the bottom surface of the concave portion. The LED chip 16 is mounted on the metal pattern portion, and is electrically connected to the pattern (not shown) connected to the other electrode 17b by the Au wire 18. And it has a structure cast with a transparent resin 19 for sealing. As shown in FIG. 14, the chip component type LEDs 15 are mounted side by side on the substrate 21 in a horizontal position. Then, the light guide plate 22 is moved from its end face 22a to the chip component type L.
It is arranged to take in the light emitted from the ED 15 and used as a backlight source for liquid crystal.

FIG. 15 shows a chip component type LED having a structure different from those of FIGS. 10 and 13. In this chip component type LED 25, two LED chips 29 (only one of which is shown) are mounted on a pattern 28 connected to one electrode 27a on a substrate 26, and connected to the other electrode 27b by an Au wire 30. Is electrically connected to the pattern 31 formed. Then, a high-viscosity light-transmitting resin 32 is formed in a hemispherical shape by printing, and the surrounding area is further subjected to transfer molding to form a light-shielding white resin 33.
Seal with. Furthermore, it has a structure divided at the center of the two LED chips 29,29.

The chip component type LED 25 uses the divided surface at the time of the division as a light emitting surface. In that case,
As shown in FIG. 16, a plurality of chip component LEDs 25 are mounted in a row on a substrate 35, and the light guide plate 36 is mounted on the substrate 35 with the light emitting surface (divided surface) of the chip component type LED 25 facing the end surface 36 a of the light guide plate 36. Attach to Then, the light emitted from the chip component type LED 25 is transmitted to the end face 36 of the light guide plate 36.
By taking in from a, it is used as a backlight source for liquid crystal.

As described above, the chip component type LED 25 shown in FIG. 15 which is of the side emission type is mounted on the mounting substrate 35 without being turned over, and the mounting substrate 35 and the light guide plate 36 are parallel. Has the advantage that the assembly process is simplified.

[0009]

However, the above-mentioned conventional chip component type LED for a backlight light source has the following problems.

[0010] 1. In the case of the chip component type LED 8 having a structure as shown in FIG. 10, since the directivity angle is wide, the brightness is insufficient for a backlight light source. Therefore, it is necessary to increase the brightness, which is disadvantageous for a portable information terminal from the viewpoint of price, current value, and the like.

2. When the chip component type LED 8 is used as shown in FIG. 11, the light guide plate 10 needs to be perpendicular to the substrate 9, and the assembly process of the product becomes complicated.

3. When the above-mentioned chip component type LED 8 is used as shown in FIG. 12 or when the chip component type LED 15 having the structure shown in FIG. 13 is used as shown in FIG. Since the mounting is performed, the area of the electrodes 2, 17 of the chip components LED 8, 15 connected to the patterns on the mounting substrates 11, 21 is small, and the chip components LED 8, 15 are likely to be displaced during solder mounting. Accuracy deteriorates.

4. In the case of the chip component type LED 25 having the structure shown in FIG. 15, the shape stability when the light transmitting resin 32 serving as the light emitting surface is formed in a hemispherical shape, and the double sealing of the resin 32 and the white resin 33 are performed. There is a problem in the stop structure, etc., the manufacturing process is complicated, and mass productivity is not good.

5. Further, in the case of the chip component type LED 25, since light is shielded by the colored resin (white resin) 33, there is light leakage and the like, and light shielding characteristics and reflection characteristics are not good.

Accordingly, an object of the present invention is to provide a chip component type LED having a stable light emitting surface shape, good mounting accuracy, good light shielding characteristics and reflection characteristics, and a simple assembly process.
It is to provide a manufacturing method thereof.

[0016]

In order to achieve the above object, a chip component type LED according to a first aspect of the present invention comprises a first substrate on which an LED chip is mounted, a through-groove formed on a side surface, and the above-mentioned through-groove. A second substrate mounted on the first substrate so as to surround the LED chip, a third substrate mounted on the second substrate and covering the through groove, A light-transmitting resin for sealing the LED chip, and a surface of the light-transmitting resin on a side surface of the second substrate is a light emitting surface.

According to the above configuration, since the shape of the light emitting surface is determined by the shape of the through groove formed in the second substrate, the shape stability of the light emitting surface is improved. Further, since the so-called side emission type in which the side surface of the substrate is a light emission surface, when the light guide plate is mounted on the mounting substrate and the emitted light is taken in from the end surface of the light guide plate, the light guide plate is parallel to the mounting substrate without being turned over. It is attached. Therefore, the mounting accuracy is improved and the product assembling process is facilitated.

Further, the chip component type LE of the first invention is provided.
D preferably forms a metal film on the inner wall of the through groove and forms a metal film on the surface of the third substrate on the side of the through groove.

According to the above configuration, the periphery of the through groove is shielded from light by the metal film. Therefore, the light shielding characteristics and the reflection characteristics are improved as compared with the case where the light is shielded by the colored resin.
Furthermore, since directivity of light is generated in the direction of the light emitting surface,
Sufficient brightness can be obtained for a backlight light source.

Further, the method of manufacturing a chip component type LED according to the second invention comprises a step of bonding a substrate on which an LED chip is mounted and a holed substrate having a through hole to form a bonded substrate; The LE on the substrate in the through hole
A step of die-bonding the D chip, a step of wire bonding to the LED chip after the die bonding, and a step of filling the through hole after the wire bonding with a light transmitting resin and sealing the LED chip with a resin. And a step of bonding an upper substrate on the perforated substrate after the resin sealing, and a step of dividing at a position of the through hole after bonding the upper substrate.

According to the above configuration, since the shape of the light exit surface is determined by the shape of the through hole formed in the perforated substrate, the shape stability of the light exit surface is improved. Further, since the so-called side emission type in which the division surface is a light emission surface, when the light guide plate is mounted on the mounting substrate and takes in the emitted light from the end surface of the light guide plate, the light guide plate is parallel to the mounting substrate without being turned over. It is attached. Therefore, the mounting accuracy is improved and the product assembling process is facilitated.

Further, the chip component type LE according to the second aspect of the present invention.
The method of manufacturing D includes forming a metal film on the inner wall of the through hole,
It is desirable to form a metal film on the surface of the upper substrate on the side of the through hole.

According to the above configuration, the periphery of the through hole is shielded from light by the metal film. Therefore, the light shielding characteristics and the reflection characteristics are improved as compared with the case where the light is shielded by the colored resin.
Furthermore, since directivity of light is generated in the direction of the light emitting surface,
Sufficient brightness can be obtained for a backlight light source.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is an external view of a chip component type LED according to the present embodiment.

Chip-part type LED according to the present embodiment
In 41, a second substrate 43 is thermocompression-bonded on a first substrate 42 via a resin adhesive sheet. On the side surface of the second substrate 43, a through groove having a semicircular cross section is formed so that the LED chip 44 can be mounted on the first substrate. Then, one electrode 45 provided on the first substrate 42
On the pattern 46 connected to a, the LED chip 44
Is mounted, and a pattern 48 is formed by an Au wire 47.
And is electrically connected to the other electrode 45b via the.

The semicircular through-groove for mounting the LED chip 44 provided on the second substrate 43 is filled with a light-transmitting resin 49, and the third substrate 50 is provided on the upper surface of the second substrate 43. It is pasted. Thus, the first substrate 42
The LED chip 44 mounted thereon is sealed.
The metal pattern 51 is formed on the entire surface of the third substrate 50 on the side of the second substrate 43, and the inner surface of the through groove in the second substrate 43 has a metal through-hole structure.

The chip component type LED 41 having the above configuration is
This is a so-called side emission type in which light emitted from the ED chip 44 is extracted from the light transmitting resin 49 in parallel with the surface of the first substrate 42 and used. Therefore, similarly to FIG. 16, a plurality of chip component type LEDs 41 are mounted in a row on a mounting board, and the light guide plate is attached in parallel with the mounting board with the light emitting surface of the chip component type LED 41 facing the end surface of the light guide plate. Therefore, when the light emitted from the side of the chip component type LED 41 is taken in from the end face of the light guide plate, it is not necessary to mount the chip component type LED 41 sideways like the chip component type LED shown in FIG.

For this reason, the area of the electrode 45 of the chip component type LED 41 connected to the pattern on the mounting board is large, the displacement of the chip component type LED 41 hardly occurs at the time of solder mounting, and the mounting accuracy can be improved. Also,
Since the mounting substrate does not need to be perpendicular to the light guide plate, the product assembling process can be facilitated.

FIG. 2 shows a chip component type LED 4 having the above configuration.
3 is a process flowchart illustrating a manufacturing procedure of FIG. First,
According to the process flowchart of FIG.
The manufacturing procedure of D41 will be briefly described.

In step S1, a perforated substrate 43, which will later become the second substrate 43, is thermocompression bonded onto the substrate 42, which will later become the first substrate 42. Then, the LED chip 44 is mounted in a through-hole that becomes the above-mentioned through-groove in the perforated substrate 43 later. In step S2, the LED chip 44
It is connected to the pattern 48 by the Au wire 47. In step S3, a light transmissive resin 49 is cast into the holes of the perforated substrate 43 on which the LED chips 44 are mounted. In step S4, the upper substrate 50, which will be the third substrate later, is bonded to the upper surface of the perforated substrate 43 with resin. In step S5, the bonding resin is cured. Step S6
Then, the formed substrate is diced, and a chip component type LED 41 is obtained.

Hereinafter, each of the manufacturing steps of the chip component type LED 41 will be described in detail. (1) Die Bonding / Wire Bonding Step As shown in FIG. 3, a perforated substrate 43 is bonded onto a substrate 42 on which a pattern 46 for die bonding the LED chip 44 is formed. LE
The D chip 44 is die-bonded. In this case, the die bonding positions are on the patterns 46a and 46b on the substrate 42 as shown in FIG. 4 (a partially enlarged plan view of FIG. 3). Further, the wire bonding by the Au wire 47 is performed by using the patterns 48a and 48b from the LED chips 44a and 44b in FIG.
Done for However, in FIGS. 3 and 6 to 8, one hole 56 is represented by one LED chip 44.

FIG. 5 shows the substrate 42 and the perforated substrate 4.
3 shows a bonding structure with the substrate 3 (corresponding to a section taken along line BB ′ in FIG. 3). The substrate 42 is provided around the glass epoxy substrate 52,
A metal through hole 53, a pattern 46 to which the LED chip 44 is die-bonded, and a pattern 48 to be wire-bonded are formed. In addition, the perforated substrate 4
In No. 3, a metal through hole 54 is formed around the hole. Then, the substrate 42 having the above-described cross-sectional structure and the perforated substrate 43 are bonded by thermocompression bonding via the resin adhesive sheet 55.

(2) Resin Casting As shown in FIG. 6, the dispenser 5 is inserted into the hole 56 of the perforated substrate 43 in a state where the wire bonding is completed.
The light-transmissive resin 49 is cast by 7. Alternatively, as another method, the squeegee 58 is slid in the direction of arrow C as shown in FIG.
6 may be performed by a printing method in which the light transmitting resin 49 is poured.

After the casting of the resin or after the printing of the resin, if bubbles may be mixed into the light transmitting resin 49, it is necessary to perform vacuum defoaming.

(3) Lamination of Substrate FIG. 8 shows a state in which the upper substrate 50 is laminated on the perforated substrate 43 (a perspective view from above). An upper substrate 50 having a metal pattern 51 (see FIG. 1) formed on the entire surface on one side is adhered to the upper surface of the perforated substrate 43 on which the light transmitting resin 49 is cast, with the metal pattern 51 side inward. It is pressed to remove the light transmitting resin 49.

(4) Resin Curing The resin is cured by an oven with the bonded substrates 42, 43, and 50 pressed down.

(5) Dicing FIG. 9 is a perspective view of the upper surface of the substrate after the light transmitting resin 49 is cured. As shown in FIG.
The substrate after is cured is diced along the dotted line. By doing so, a chip component type LED 41 having a divided surface as a light emitting surface as shown in FIG. 1 is obtained.

As described above, the present chip component type LED 41
After casting the light-transmitting resin 49 into a cylindrical hole drilled through the perforated substrate 43, the hole of the perforated substrate 43 is
I try to split it. Therefore, the shape of the light emitting surface is determined by the shape of the hole formed in the perforated substrate 43.
Therefore, the problem of the shape stability of the light emitting surface when casting the light transmitting resin 49 can be solved.

The chip component type LED 41 is provided with a metal through-hole 5 around the hole on the perforated board 43.
4 are formed. Further, the perforated substrate 4 of the upper substrate 50
A metal pattern 51 is formed on the surface on the third side. Therefore, the light-shielding characteristics and the reflection characteristics can be improved as compared with the structure in which the colored resin (white resin) 33 shields the light as in the conventional chip component type LED 25 shown in FIG. Further, since the light directivity can be provided in the direction of the light emitting surface, sufficient brightness can be obtained for a backlight light source.

Further, by reducing the thickness of the perforated substrate 43, the thickness of the chip component type LED 41 itself can be reduced. Further, since a double sealing structure of the light transmitting resin and the white resin is not used, the degree of freedom of the characteristics of the light transmitting resin is increased.

[0041]

As is clear from the above, the chip component type LED of the first invention has a second structure in which a through groove is formed on the side surface.
A structure in which the substrate is sandwiched between the first substrate and the third substrate on which the LED chips are mounted, and the LED chips in the through-grooves are sealed with a light-transmitting resin. Since the surface of the light-transmitting resin is used as the light emitting surface, the shape of the light emitting surface can be determined by the shape of the through-groove, and the shape stability of the light emitting surface can be improved. In addition, since the side surface of the substrate is used as the light emitting surface, the light guide plate can be attached to the mounting substrate in parallel without being turned over when mounting on the mounting substrate and taking in the emitted light from the end surface of the light guide plate. Therefore, the mounting accuracy can be improved, and the assembly process of the product can be facilitated.

Further, the chip component type LE of the first invention is provided.
D forms a metal film on the inner wall of the through-groove and forms a metal film on the surface of the third substrate on the through-groove side, so that the periphery of the through-groove can be shielded by the metal film. Therefore, the light shielding characteristics and the reflection characteristics can be improved as compared with the case where the light is shielded by the colored resin. Furthermore, since it has directivity of light in the direction of the light emitting surface, it is possible to obtain sufficient brightness for a backlight light source.

Further, a method of manufacturing a chip component type LED according to a second aspect of the present invention includes a step of forming a bonded substrate of a substrate on which an LED chip is mounted and a perforated substrate having a through hole.
A step of die-bonding the LED chip on the substrate; a step of wire-bonding the LED chip to the LED chip;
Since the method includes a step of sealing the chip with a resin, a step of bonding an upper substrate on the holed substrate, and a step of dividing the chip at the position of the through hole, the shape of the light emitting surface is determined by the shape of the through hole. Thus, the shape stability of the light emitting surface can be improved. Also,
When the light guide plate is mounted on the mounting substrate and the emitted light is taken in from the end face of the light guide plate, the light guide plate can be attached in parallel to the mounting substrate without falling down. Therefore, the mounting accuracy can be improved, and the assembly process of the product can be facilitated.

The chip component type LE according to the second aspect of the present invention.
The method of manufacturing D includes forming a metal film on the inner wall of the through hole,
If a metal film is formed on the surface of the upper substrate on the side of the through hole, the periphery of the through hole can be shielded from light by the metal film. Therefore, the light shielding characteristics and the reflection characteristics can be improved as compared with the case where the light is shielded by the colored resin. Furthermore, since it has directivity of light in the direction of the light emitting surface, it is possible to obtain sufficient brightness for a backlight light source.

[Brief description of the drawings]

FIG. 1 is an external view of a chip component type LED of the present invention.

FIG. 2 is a process flowchart showing a manufacturing procedure of the chip component type LED shown in FIG.

FIG. 3 is an external view showing a state in which a perforated substrate is bonded to a substrate and an LED chip is die-bonded.

FIG. 4 is a partially enlarged plan view of FIG. 3;

FIG. 5 is a partial cross-sectional view showing a bonding structure of the substrate and the perforated substrate in FIG.

FIG. 6 is an explanatory view of casting a light-transmitting resin on a substrate having holes.

FIG. 7 is an explanatory view of a light transmitting resin casting different from FIG.

FIG. 8 is a diagram showing a state in which an upper substrate is stuck on a perforated substrate.

FIG. 9 is an explanatory diagram of a dicing position after the light transmitting resin is cured.

FIG. 10 is a view showing a structure of a conventional chip component type LED.

11 is a diagram showing a mounting example of the chip component type LED shown in FIG. 10;

FIG. 12 is a diagram illustrating a mounting example different from FIG. 11;

13 is a conventional chip component type LE different from FIG.
It is a figure which shows the structure of D.

14 is a diagram showing a mounting example of the chip component type LED shown in FIG.

FIG. 15 is a view showing a structure of a conventional chip component type LED different from FIGS. 10 and 13;

16 is a diagram showing a mounting example of the chip component type LED shown in FIG.

[Explanation of symbols]

41: chip component type LED, 42: substrate (first substrate),
43: perforated substrate (second substrate), 44: LED
Chip, 45a, 45b ... electrode, 46,4
8 ... pattern, 47 ... Au wire, 49
... light-transmitting resin, 50 ... upper substrate (third substrate), 51 ... metal pattern, 54
... metal through hole, 55 ... resin adhesive sheet.

Claims (4)

[Claims] A first substrate on which a light emitting diode chip is mounted; a first substrate having a through groove formed on a side surface; and a through groove mounted on the first substrate so that the through groove surrounds the light emitting diode chip. A second substrate mounted on the second substrate to cover the through-groove; and a light-transmitting resin sealing the light-emitting diode chip in the through-groove. A chip component type light emitting diode, wherein a surface of a light transmitting resin on a side surface of a substrate is a light emitting surface. 2. The chip component type light emitting diode according to claim 1, wherein a metal film is formed on an inner wall of the through groove, and a metal film is formed on a surface of the third substrate on the side of the through groove. A chip component type light emitting diode, characterized in that: 3. A step of bonding a substrate on which a light emitting diode chip is mounted and a perforated substrate having a through hole to form a bonded substrate; and mounting the light emitting diode chip on the substrate in the through hole. A step of die bonding, a step of wire bonding to the light emitting diode chip after the die bonding, and a step of filling the through hole after the wire bonding with a light transmitting resin and sealing the light emitting diode chip with a resin. A chip component mold comprising: a step of bonding an upper substrate on the holed substrate after the resin sealing; and a step of bonding the upper substrate and then dividing at a position of the through hole. A method for manufacturing a light emitting diode. 4. The method for manufacturing a chip component type light emitting diode according to claim 2, wherein a metal film is formed on an inner wall of the through hole, and a metal film is formed on a surface of the upper substrate on a side of the through hole. A method for manufacturing a chip component type light emitting diode, characterized in that: