JP3227295B2 - Light emitting diode manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a surface mount-type light-emitting <br/> diodes thin.

[0002]

2. Description of the Related Art Conventionally, as a surface-mount type light emitting diode, a light emitting diode having a laminated board such as a glass epoxy resin laminated board as a substrate has been provided, and a concave portion is formed on this substrate by counterboring using a drill or the like. The light emitting diode is mounted in the concave portion and manufactured.
However, the bottom surface serving as the die bonding surface of the recess formed by the counterbore processing is not flat, and the light emitting diode cannot be mounted by die bonding.

Therefore, as shown in FIG. 12, a circuit pattern 3 is provided on a substrate 1 made of a laminate such as a glass epoxy resin laminate, and a frame-like reflection case 14 is adhered to the surface of the substrate 1. The concave portion 2 is formed inside the reflective case 14 without the need for counterboring, and the light emitting diode chip 4 is mounted on the surface of the substrate 1 in the concave portion 2. Then, after bonding a wire 5 such as a gold wire, a liquid transparent resin 15 is poured into the concave portion 2 to seal the light emitting diode chip 4 and the wire 5 to manufacture a surface mount light emitting diode. (In FIG. 12, the circuit pattern 3 is indicated by oblique lines). However, in this case, there is a problem that the thickness of the reflection case 14 is added to the thickness of the substrate 1, so that the overall thickness becomes large and the thickness cannot be reduced.

For this reason, a light emitting diode as disclosed in Japanese Patent Application Laid-Open No. 1-283883 has been provided. As shown in FIGS. 13 (a) and 13 (b), a substrate 1 provided with a concave portion 2 by injection molding of a thermoplastic resin is formed and subjected to three-dimensional patterning to form a circuit pattern on the bottom surface of the concave portion 2 as shown in FIGS. After the formation of the light emitting diode chip 3, the light emitting diode chip 4 is mounted in the recess 2 and the wire 5 is bonded between the light emitting diode chip 4 and the circuit pattern 3 in the recess 2; And the light emitting diode chip 4 and the wire 5 are sealed to manufacture a surface mounted light emitting diode (the circuit pattern 3 is shown by oblique lines in FIG. 13).

[0005]

However, Japanese Patent Application Laid-Open No.
In FIGS. 13 (a) and 13 (b) of JP-A-283883, the depth of the concave portion 2 is set above the light emitting diode chip 4 in order to seal the light emitting diode chip 4 and the wire 5 in the concave portion 2. Therefore, it is necessary to form the substrate 5 deeply so that the wire 5 protruding from the substrate 1 can be accommodated. As a result, the thickness of the substrate 1 is increased. Further, in order to form a circuit pattern 3 for connecting the light emitting diode chip 4 and the wire 5 on the bottom surface of the concave portion 2, it is necessary to increase the area of the concave portion 2, and the substrate 1 also needs to be enlarged accordingly. Was. Moreover, in the case of FIGS. 13A and 13B, the concave portion 2
Are inclined to form the reflection inclined surface 16, and the reflection inclined surface 16 further increases the area of the concave portion 2 and further increases the size of the substrate 1.

As described above, even in Japanese Patent Application Laid-Open No. 1-283883, there is a problem that it is difficult to reduce the size and thickness. The present invention has been made in view of the above points, and it has been proposed that a small-sized and thin light-emitting diode can be efficiently used.
It is an object of the present invention to provide a method for manufacturing a light emitting diode which can be manufactured with high efficiency.

[0007]

According to the present invention, there is provided a method for manufacturing a light emitting diode , comprising the steps of:
The chip 4 is mounted on the light emitting diode chip 4 and the substrate 1.
Wire bonding with circuit pattern 3 on the surface
A transparent tree covering the photodiode chip 4 and the wire 5
A resin is molded to form a mold portion 6 on the surface of the substrate 1.
In manufacturing the light emitting diode formed by
A number of recesses 2 are arranged in a plurality of rows on the surface by resin molding
And a separation slit 18 for separating each row of the recess 2.
A beam forming plate 17 is prepared, and the surface of the forming plate 17 is plated.
After forming the circuit pattern 3 between the concave portions 2 adjacent to each other
In the forming plate 1, a line passing through each separation slit 18 is used.
7 is cut to form the recess 2 and the circuit pattern 3.
, And a large number of substrates 1 having the same are separated .

[0008]

[0009]

[0010]

The concave portion 2 is formed on the surface of the substrate 1 and the substrate 1
A circuit pattern 3 is provided on the surface of the light emitting diode chip 4 and the light emitting diode chip 4 is
The wire 5 is bonded to the circuit pattern 3 on the surface of the substrate 1 by wire bonding.
There is no need to provide a space for connecting
The substrate 1 may be formed to a depth and size that can accommodate only the light emitting diode chip 4, and the substrate 1 can be made thin and small.

[0011]

The present invention will be described below in detail with reference to examples. FIG.
2A and 2B show an embodiment of the present invention, and the manufacturing process will be described with reference to FIG. First, a substrate 1 is prepared by injection molding of a thermoplastic resin. As the thermoplastic resin used for this molding, a resin having heat resistance to heat treatment at the time of soldering and a plating property is preferable. For example, a liquid crystal polymer ("Vectra C" manufactured by Polyplastics Co., Ltd.)
-820 "), polyetherimide (PEI:" Ultem "manufactured by General Electric Co., Ltd.), polyphthalamide (Amoco" Amodel ", etc.), and polyphenylene oxide (PPS: manufactured by Dainippon Ink and the like) Can be used. As a molding machine for molding the resin, it is preferable to use an ultra-high-speed injection molding machine having an injection speed of 700 mm / sec or more so that the thin portion at the bottom of the concave portion 2 is sufficiently filled with the resin. A “PS80E5H molding machine” manufactured by Nissei Plastic Industry Co., Ltd. can be used.

As described above, the substrate 1 having the concave portion 2 formed on the surface as shown in FIG. 3A can be formed by molding the resin. Here, a large number of substrates 1 are made continuous and formed into a multi-piece molding plate 17 as shown in FIG. In FIG. 4, reference numeral 18 denotes a separation slit separating each row of the substrate 1.

[0013] Next, formed by a process such as soft etching
After roughening the entire surface of each substrate 1 constituting the shaped plate 17 , electroless plating such as electroless copper plating is performed, and FIG.
As shown in (b), an electroless plating layer 19 having a thickness of about 1 μm is formed on the entire surface of each substrate 1 constituting the molded plate 17 . Next, both sides of each substrate 1 forming the forming plate 17 are shown in FIG.
The dry film resist 20 is laminated as described above. As the dry film resist 20, a resist having plating resistance such as copper plating, nickel plating, or gold plating is used.
A μm negative type can be used. Then, as shown in FIG. 3D, the mask 21 is overlaid on the surface of the dry film resist 20 and exposed, and the mask 21 is removed and developed, so that the circuit pattern 3 is not formed as shown in FIG. The dry film resist 20 is removed leaving a portion to perform patterning. FIG. 5 shows a patterning state of the entire molding plate 17 (in FIG. 5, the dry film resist 20 is indicated by oblique lines).

Next, each substrate 1 constituting the molded plate 17 is subjected to electroplating such as electrocopper plating, and the surface of the electroless plating layer 19 which is not covered with the dry film resist 20 is formed as shown in FIG. The electroplating layer 22 is formed as described above, and further, electroplating nickel and gold are performed to form the surface plating layer 23 as shown in FIG.
In this way, the electroless plating layer 19 and the electroplating layer 2
2 and a surface plating layer 23. The thickness of the circuit pattern 3 is, for example, 20 μm for copper, 5 μm for nickel, and 0.3 μm for gold.
It is. After this, the dry film resist 20 is
After peeling as in (h), dry film resist 2
The electroless plating layer 19 exposed by the separation of 0 is soft-etched and removed as shown in FIG.

As described above, as shown in FIG.
7, a circuit pattern 3 can be formed on each substrate 1 (the circuit pattern 3 is shown by oblique lines in FIG. 6),
By cutting the molded plate 17 at the position indicated by the chain line in FIG.
It can be separated into In the embodiment of FIG. 1, the circuit pattern 3 is formed by a pair of circuit patterns 3a on one side of the substrate 1 and a circuit pattern 3b on the other side, which are separated from each other. 1, the circuit pattern 3 is indicated by oblique lines), and each circuit pattern 3
The end portions of a and 3b are formed as extraction electrode terminal portions 9 from the side end surface of the substrate 1 to the lower surface. A die bonding portion 24 is formed by plating on the bottom surface of the concave portion 2 so as to form a part of the circuit pattern 3b, and a reflection layer is formed on the entire inner surface of the concave portion 2 so as to form a part of the circuit pattern 3b. Reference numeral 25 is formed by plating so as to reflect light from the light emitting diode chip 4 to increase luminous efficiency.

The light emitting diode chip 4 is fixed in the recess 2 by die bonding or the like, so that the light emitting diode chip 4 is mounted in a state of being electrically connected to the circuit pattern 3b. The light emitting diode chip 4 is electrically connected to the circuit pattern 3a by bonding a wire 5 such as a gold wire between the light emitting diode chip 3a and the transparent resin 3a. By providing the portion 6 on the surface of the substrate 1, a surface-mounted light emitting diode as shown in FIGS. 1 and 2 can be produced. As the transparent resin for molding the mold portion 6, it is preferable to use an epoxy resin or the like containing a filler for scattering light. By setting the substrate 1 in a mold and performing injection molding or the like, FIG. The molding part 6 is formed by molding without the necessity of using the reflection case 14 as in the conventional example.

In the surface-mounted light emitting diode produced as described above, the light emitting diode chip 4 and the substrate 1
Since the wire 5 is connected to the circuit pattern 3a on the surface of the recess 2, it is not necessary to house the wire 5 in the recess 2 and it is necessary to provide a space for connecting the wire 5 on the bottom surface of the recess 2. The recess 2 may be formed to have a depth and a size that can accommodate only the light emitting diode chip 4. Therefore, the thickness of the substrate 1 can be made thinner and smaller than that of the conventional device shown in FIG. 13, and the light emitting diode can be made thinner and smaller. Further, when a transparent resin containing a filler for scattering light is used as the transparent resin for molding the mold portion 6 as described above, the reflection efficiency is increased, and the reflection inclined surface 16 as shown in FIG. Need not be provided on the inner surface of the recess 2, and the inner surface of the recess 2 can be formed in a plane perpendicular to the surface of the substrate 1. In this regard, the size of the substrate 1 can be reduced. You can do it.

In the embodiment shown in FIG. 1, for example, the size of the substrate 1 is 2.1 mm × 1.25 mm × thickness 0.40 mm, the size of the concave portion 2 is 0.7 mm in diameter × 0.15 mm in depth, Is formed to have a thickness of 0.3 mm, and the insulation distance between the circuit patterns 3a and 3b is set to 0.1 mm.
FIG. 7 shows another embodiment of the present invention (the circuit pattern 3 is shown by oblique lines in FIG. 7), in which a plurality of light emitting diode chips 4 are mounted in the recess 2. For example, by mounting light emitting diode chips 4 of two colors such as red and green, a surface mounted light emitting diode of three colors can be produced. Of course, the number of mounted light emitting diode chips 4 is not limited to two (two types), and if three light emitting diode chips 4, for example, three types of red, green and blue light emitting diode chips 4 are mounted, A full-color surface-mounted light-emitting diode can be manufactured. In this embodiment, a plurality of light emitting diode chips 4
Bonding portion 2 on the bottom surface of concave portion 2 serving as common electrode
Reference numeral 4 denotes a conductive connection through a through hole 26 to a circuit pattern 3b formed on the back surface of the substrate 1. Of course, the die bonding portion 24 may be formed separately for each light emitting diode chip 4 and the circuit pattern 3b may be formed separately.

FIG. 8 shows still another embodiment of the present invention, in which a heat radiation land 7 is provided at a position corresponding to the concave portion 2 on the back surface of the substrate 1 (in FIG. The radiating lands 7 are indicated by oblique lines). The heat radiating land 7 is a metal film formed by metal plating such as copper plating and is formed in a circular shape having a diameter larger than the diameter of the concave portion 2.
By providing the radiating land 7 in this manner, the heat generated by the light emitting diode chip 4 mounted in the concave portion 2 can be efficiently radiated, and the thin portion at the bottom of the concave portion 2 is reinforced by the radiating land 7. Is what you can do.

In the embodiment shown in FIG. 9, a heat radiating plate 8 is provided by insert molding at a position corresponding to the concave portion 2 on the back surface side of the substrate 1 (in FIG. 9, the circuit pattern 3 is formed).
And the radiator plate 8 is indicated by oblique lines). The heat radiating plate 8 is made of a material having high thermal conductivity and electrical conductivity, such as a metal plate such as a copper plate, and is formed in a circular shape having a diameter larger than the diameter of the concave portion 2. The bottom surface of the concave portion 2 is formed by the heat sink 8 so as to be exposed to the outside. The heat radiating plate 8 is electrically connected to the circuit pattern 3b via the reflection layer 25, and the light emitting diode chip 4 is mounted on the heat radiating plate 8 forming the bottom surface of the concave portion 2 so that the light emitting diode chip 4 is formed. Can be electrically connected to the circuit pattern 3b. By providing the heat radiating plate 8 in this manner, the heat generated by the light emitting diode chip 4 mounted in the concave portion 2 can be efficiently radiated, and the thin portion at the bottom of the concave portion 2 is reinforced by the heat radiating plate 8. Is what you can do.

In the embodiment shown in FIG. 10, when the mold 6 is provided on the surface of the substrate 1 by molding with a transparent resin, the surface of the mold 6 is formed to have the surface shape of a lens such as a convex lens. By forming the mold portion 6 in the shape of a lens as described above, light from the light emitting diode chip 4 can be condensed to increase luminous efficiency.

In the embodiment shown in FIG. 11, a concave step portion 10 is formed at the lower end of the side end of the substrate 1 provided with the electrode terminal portion 9 so as to open on the side surface and the back surface. In mounting the light emitting diode on the electrode 28 and the like, the solder 29 is attached to each of the electrode terminal portions 9, so that the solder 29 can be prevented from being filled in the concave step portion 10 and reaching the other electrode terminal portion 9. However, even if the distance between the electrode terminals 9 is reduced due to the miniaturization of the light emitting diode, the electrode terminals 9
Is designed to prevent short-circuiting with the solder 29 to enhance insulation reliability, and to further improve solderability.

[0023]

As described above, according to the present invention , the recessed portion of the substrate
Light emitting diode chip mounted with light emitting diode chip
Wire bonding with the circuit pattern on the surface of the board
And transparent to cover the light emitting diode chip and wire
Molding resin to provide a mold part on the surface of the substrate
Since the light emitting diode is formed by the above, it is not necessary to put the wire in the concave portion, and it is not necessary to provide a space for connecting the wire on the bottom surface of the concave portion,
The recess may be formed to a depth and size that can accommodate only the light-emitting diode chip, and the thickness of the substrate can be made thinner and smaller, and the light-emitting diode can be made thinner and smaller. Things .

[0024]

[0025]

Further, to produce a molded plate having a separation slit which separates each column of recesses provided with a number of recesses in the surface and the resin molded multiple column array, the circuit pattern by plating on the surface of the molded plate after forming the, by cutting the molded plate by a line passing across each separation slit between the recess adjacent, since the so that to separate the multiple substrates having a recess and a circuit pattern, a single molding A large number of substrates can be manufactured from a plate, and the production efficiency of light-emitting diodes can be increased.Moreover, when the substrate is separated from the formed plate, by cutting the formed plate in one direction passing through each separation slit. The substrate can be separated by the cutting line and the separation slit, and the work of separating the substrate from the molded plate can be easily performed.
Things .

[Brief description of the drawings]

1 shows an embodiment of the present invention, wherein (a) is a plan view, (b) is a front sectional view, and (c) is a bottom view.

FIG. 2 is a perspective view of the embodiment.

FIG. 3 is a cross-sectional view of each of the steps, showing a manufacturing method of the above.

FIG. 4 is a plan view of a formed plate in the step of FIG.

FIG. 5 is a plan view of a formed plate in the step of FIG.

FIG. 6 is a plan view of the formed plate in the step of FIG. 3 (i).

FIG. 7 shows another embodiment of the present invention, in which (a)
Is a plan view, (b) is a front sectional view, (c) is a bottom view,
(D) is a front view.

FIG. 8 shows still another embodiment of the present invention;
(A) is a plan view, (b) is a front sectional view, and (c) is a bottom view.

FIG. 9 shows still another embodiment of the present invention;
(A) is a plan view, (b) is a front sectional view, and (c) is a bottom view.

FIG. 10 is a front sectional view showing still another embodiment of the present invention.

11A and 11B show still another embodiment of the present invention, wherein FIG. 11A is a front sectional view, FIG. 11B is a bottom view, and FIG. 11C is a bottom perspective view.

FIG. 12 shows a conventional example, in which (a) is a plan view,
(B) is a front sectional view.

FIG. 13 shows another conventional example, in which (a),
(B) is a front sectional view, respectively.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Concave part 3 Circuit pattern 4 Light emitting diode chip 5 Wire 6 Mold part 7 Heat radiating land 8 Heat radiating plate 9 Electrode terminal part 10 Concave step part17 Molded plate 18 Separation slit 24 Die bonding part 26 Through Hole

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-354073 (JP, A) JP-A-5-11718 (JP, A) JP-A-5-46100 (JP, A) 29659 (JP, A) Japanese Utility Model Hei 5-8959 (JP, U) Japanese Utility Model Sho 64-13167 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 33/00

Claims (1)

(57) [Claims] A light emitting diode chip is provided in a recess of a substrate.
Mounted light emitting diode chip and circuit pattern on substrate surface
Wire bonding to the light emitting diode chip.
Mold the transparent resin to cover the loop and wire
Light emitting diode formed by providing a mold part on the surface of the substrate
When manufacturing a resin, a large number of
Provide multiple rows of recesses and separate each row of recesses
A molded plate with a separation slit
After forming a circuit pattern by plating
Between the forming plates with a line passing across each separation slit
Has a concave portion and a circuit pattern by cutting
A large number of substrates separated from each other.
A method for manufacturing a photodiode.