JP2003188421A - Light emitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitter which efficiently utilizes lights emitted from a light-emitting element, and comprises a wall containing a light reflection part and a lead frame. <P>SOLUTION: Lead frames 5, 6 on a positive pole side and a negative pole side are fitted on a fitting body 2 having a bottom 2A and walls 2C, 2E so as to come into contact with the bottom individually and be away from each other. A light-emitting element 1 is fitted on the one lead frame which is electrically connected to one electrode of the light-emitting element, and the other electrode of the light-emitting element is electrically connected to the other lead frame. On the other hand, a surface on a side of the light-emitting element of the wall is an inclined surface 2F, and a light reflection part 2J for reflecting lights emitted from the light-emitting element 1 is formed on the inclined surface. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device having a light emitting element in a mounting body, and more particularly to a light emitting device in which light emitted from the light emitting element is efficiently reflected in a target direction to improve light utilization efficiency. Is.

[0002]

2. Description of the Related Art A light emitting diode (LED) is used as a light source for a front light or a backlight of a liquid crystal display device or as a light source of various display devices.
The light emitting device consisting of e) is widely used. In general, this type of LED light-emitting element is formed by providing a positive electrode and a negative electrode on a light emitting semiconductor substrate such as ZnSe. The semiconductor substrate is housed in a package made of resin or the like and external to the package. It is provided with a connecting electrode. FIG. 13 shows an example of the structure of this type of LED light emitting device. In the LED light emitting device A of this structure example,
A substrate 100 made of glass epoxy resin or the like is provided,
A U-shaped lead electrode plate 10 having a folded shape at both ends thereof.
2, 103 are attached, and the semiconductor chip 10 as a light emitting element is mounted on the electrode plate 102 on one end of the substrate 100.
5 is attached, the electrode plate 103 on the other side of the substrate 100 is wire-bonded to the electrode on the upper side of the semiconductor chip 105 by the wire line 106, and the upper surface of the substrate 100, the semiconductor chip 105, the wire line 106 and the like are connected. A protective cover layer 107 made of a transparent resin is formed so as to cover it. An electrode portion is formed on the bottom of the semiconductor chip 105, and this electrode portion is formed on the lead electrode plate 102.
The semiconductor chip 105 is fixed to the upper surface of the semiconductor chip 105 by die bonding. The light emitting device A having the structure shown in FIG. 13 has a structure in which light is emitted from the semiconductor chip 105 by energizing the semiconductor chip 105 via the lead electrode plates 102 and 103 which also serve as electrodes.

In the light emitting device A having the structure shown in FIG.
Since the semiconductor chip 105 emits light in almost all directions around the semiconductor chip 105, the light emitted on the upper surface side of the substrate 100 in the direction perpendicular to the upper surface of the substrate can be effectively used as the emitted light from the light emitting device A. For example, the light emitted in a direction parallel to the upper surface of the substrate 100, for example, in the left-right direction or the left-right oblique direction in FIG. 13 is directed in a direction different from the target direction, so that there is a problem that it cannot be effectively used. Therefore, conventionally, a side wall 108 is provided upright on the peripheral side of the substrate 100 as shown in FIG. 14, and the side wall 108 is used to make light emitted laterally from the semiconductor chip 105 in a direction perpendicular to the substrate 100 as much as possible. There has been proposed a light emitting device B configured to guide and effectively utilize the emitted light.

[0004]

However, even with the structure of the light emitting device B shown in FIG. 14, there is a problem in that the utilization efficiency of the light emitted by the light emitting element 105 in all directions of the periphery is not sufficient. In the structure of the light emitting device B shown in FIG.
It is necessary to separately mount 08 on the substrate 100 so as not to interfere with the lead electrode plates 102 and 103. Especially, when the light emitting device B itself is a minute component of several mm square, it takes time to mount the side wall portion. However, there is a problem that the manufacturing process becomes complicated. Further, in the light emitting devices A and B shown in FIGS. 13 and 14, although the U-shaped lead electrode plates 102 and 103 are attached to both ends of the substrate 100, the attachment to the lead electrode plates 102 and 103 is performed. The strength is not sufficient, and there is a problem that it is difficult to sufficiently increase the bonding strength between the respective members when the side wall 108 is attached with the lead electrode plates 102 and 103 attached to the substrate 100.

The present invention has been made to solve the above problems, and makes it possible to efficiently use the light emitted from a light emitting element, and to provide a wall portion having a light reflecting portion and a lead frame. An object of the present invention is to provide a light emitting device in which the structure of a mounting body provided is simplified.

[0006]

In order to achieve the above object, the present invention has the following constitutions. In the light emitting device of the present invention, a positive electrode side and a negative electrode side lead frame are separately attached to an attachment body having a bottom portion and a wall portion so as to be in contact with the bottom portion, and one of the lead frames is a light emitting element. Is attached and one electrode of the light emitting element is electrically connected, while the other electrode of the light emitting element is electrically connected to the other lead frame, while the other electrode of the wall portion on the light emitting element side is connected. The surface is an inclined surface, and a light reflecting portion that reflects the light emitted from the light emitting element is formed on the inclined surface.

The light emitting element installed on the lead frame on the bottom of the mounting body emits light not only in the upper direction of the bottom but also in various peripheral directions. The light emitted toward the upper side of the bottom is easy to be effectively used, but the light emitted in the direction along the bottom of the mounting body, that is, the lateral direction has not been effectively used in the conventional light emitting device. On the other hand, in the structure in which the inclined surface is formed on the wall portion, a part of the light emitted in the lateral direction from the light emitting element is reflected by the inclined surface of the wall portion and goes to the upper side of the bottom portion. Light emitted from the element in various directions can be collected and emitted in one direction as much as possible, for example, in a direction orthogonal to the bottom of the mounting body and away from the bottom. Therefore, the brightness of the light emitting device can be improved. Further, when the light reflecting portion is formed on the inclined surface, the light is strongly reflected by the light reflecting portion, so that the light emitted from the light emitting element in various directions can be strongly condensed in one direction. A light emitting device with further improved brightness can be provided. Further, since the light emitting element is mounted on the lead frame mounted on the mounting body, the mounting strength of the light emitting element can be increased.

In the light emitting device of the present invention, the wall portion is formed at least at two opposite positions on the peripheral portion of the bottom portion, and the inclined surfaces formed on the wall portion cause the gap between the front end sides of the opposite wall portions. Is wider than the space between the base end sides of the opposing wall portions. Since the opening on the upper side of the wall provided opposite to the bottom is made wider than the opening on the lower side, when mounting the light emitting element on the bottom, a jig of the mounting device, a robot hand, etc. should be installed between the walls. It becomes easy to enter and the mountability when the light emitting element is mounted on the bottom is improved. Especially when the light emitting device is a minute part such as a few mm square, the interval between the walls is also in the unit of a few mm, so that a larger gap between the walls is advantageous for the work of mounting the light emitting element. .

The light emitting device of the present invention is characterized in that, in the structure described above, a light reflecting portion is formed on the bottom portion of the mounting body. Since the light reflecting portion is formed on the bottom of the mounting body, even light emitted from the light emitting element toward the bottom of the mounting body can be reflected by the light reflecting portion of the bottom of the mounting body. Light can be emitted in a direction away from the bottom of the mounting body, and the brightness of the light emitting device can be further improved.

The light emitting device of the present invention is characterized in that, in the structure described above, the light reflecting portion is made of an aggregate of light reflecting metal powder such as silver powder, gold powder, aluminum powder or a fluorescent paint. Further, the light reflecting portion may be formed of a light reflecting layer such as an aluminum reflecting layer. With the light reflecting portion made of these metal powders or the light reflecting portion made of a light reflecting layer such as an aluminum reflecting layer, it is possible to reflect light with a high reflectance and further improve the brightness. Even if the light reflecting portion is made of fluorescent paint, the brightness as a light emitting device can be improved.

In the light emitting device of the present invention, a bottom electrode is formed on the light emitting element, the bottom electrode is fixed on the one lead frame, and another electrode formed on the light emitting element is a lead wire. A structure connected to the other lead frame via the above can be adopted.

The light emitting device of the present invention has a structure in which a light emitting element is installed on the bottom of the mounting body, the inclined surface of the wall portion is formed in a curved shape, and the wall portion extends from the central portion of the light emitting element. When the horizontal distance to the upper end of the inclined surface is X1, the wall height from the upper surface of the bottom to the upper end of the wall is H _wall, and the inclined state of the inclined surface is R _wall , It is characterized by satisfying the relation of the following formula. _{│R wall} -{(X1-X0) ² + H _wall ² } / 2 (X1-X
0) | <0.5

The light emitting device of the present invention has a structure in which a light emitting element is installed on the bottom of the mounting body, the inclined surface of the wall is formed in a curved shape, and the upper surface of the bottom to the upper end of the wall is formed. The light emitting device according to any one of claims 1 to 7, characterized in that, when the wall height up to is H _wall and the height of the light emitting element is H, the relationship of the following equation is satisfied. . | {(H _wall -H) / (X1-X)}-1/2 ^1/2 | <
0.4

[0014]

Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to the following embodiments. 1 to 3 show a first embodiment of a light emitting device according to the present invention. In a light emitting device C of this embodiment, a light emitting element 1 made of a semiconductor chip or the like is made of a resin integrated body made of a white epoxy resin or the like. It is configured to be provided inside the box-shaped mounting body 2. The mounting body 2 has a plate-shaped bottom portion 2A having a rectangular shape in plan view, and wall portions 2B and 2B provided on four peripheral portions of the bottom portion 2A at a substantially right angle to the bottom portion 2A.
It is formed in a box shape made of C, 2D, and 2E. Of the previous wall portions 2B, 2C, 2D, and 2E, the wall portions 2B and 2D are formed on the long side of the bottom portion 2A, and the wall portion 2 is formed on the short side of the bottom portion 2A.
C and 2E are formed, the upper surface side of the mounting body 2 is an opening, and the bottom surface 2A side of the wall portions 2C and 2E is a slanted upward inclined surface (for example, the bottom portion 2A of the wall portion 2C). The inclined surface 2F is formed so that the side is thick and the upper end side of the wall 2C is thin.

The inclination angle of the inclined surface 2F is in the range of 40 to 70 ° as the inclination angle (the rising angle of the inclined surface 2F with respect to the bottom portion 2A) when a flat reflecting surface is formed from the inclined surface 2F. , And more preferably 55 °. In addition, in consideration of the further improvement of the light reflectivity, the inclined surface 2
When F is a curved surface, it is preferable to use a curved surface represented by a relational expression described later. In FIG. 2, the left and right inclined surfaces 2F
Are shown as the same angle, the inclined surfaces 2F of the left and right wall portions 2C, 2E may have different inclination angles. The right and left inclined surfaces 2F have the same inclination angle because the light emitting element 1 has the bottom portion 2A.
In the case where the light emitting element 1 is installed in the central portion of the bottom portion 2A, as shown in FIG.
(Side closer to the side), the inclined surface 2 of the wall 2C
It is preferable that the inclination angle of F is equal to the inclination angle of the wall portion 2E. The reason why the light emitting element 1 is installed on the left side of the central portion in FIG. 2 will be described later.

Next, the lead frame 5 is attached through the base end of one wall 2E (the left wall 2E in FIGS. 1 and 2) of the walls 2C and 2E, and the lead frame 5 is attached to the other. Wall part 2C
The lead frame 6 is attached by penetrating the base end portion of the right wall portion 2C in FIGS.
6 is integrated with the mounting body 2. The lead frame 5 is preferably made of a metal plate having good conductivity such as copper,
As shown in FIG. 4, in the unfolded state, it is generally L-shaped in plan view, and a fixing portion 5A having a square shape in plan view occupying about a left half of the bottom portion 2A shown in FIG. 1, and this fixing portion. The connecting portion 5B having a width narrower than 5A, and the connecting portion 5
It is composed of a connecting portion 5C extending at a right angle to B and a connecting portion 5D extending at a right angle to this connecting portion 5C. Then, in the lead frame 5, a portion of the fixed portion 5A and a portion of the connecting portion 5B following the fixed portion 5A are inserted into the groove portion 2G formed on the upper surface of the bottom portion 2A of the mounting body 2, and the mounting portion 2 is connected at the connecting portion 5B. Part of the connecting portion 5B penetrating through the wall portion 2E of the wall portion 2C and protruding to the outside of the wall portion 2C is bent along a bending line indicated by reference numeral 5f in FIG. 4 to form an outer surface of the wall portion 2E as shown in FIG. In addition to being attached, a part of the connecting portion 5C is further bent along the bending line 5g shown in FIG. 4 to be attached to the outer surface of the wall portion 2D as shown in FIG.
The connection portion 5D serves as one external connection electrode of the light emitting device C.

The other lead frame 6 is preferably made of a metal plate having good conductivity such as copper, and has an L-shaped shape obtained by removing the fixing portion 5A from the lead frame 5 shown in the developed view of FIG. That is, as shown in the development view of FIG.
It has a substantially L-shaped configuration including B, 6C, and 6D. Further, in the lead frame 6, the portion of the connecting portion 6B is inserted into the groove portion 2H formed on the upper surface of the bottom portion 2A of the mounting body 2, the connecting portion 6B penetrates the wall portion 2C of the mounting body 2, and the wall portion 2C is formed. A part of the connecting portion 6B protruding outside is bent along the bending line 6f shown in FIG. 5 to be attached to the outer surface of the other wall portion 2C, and a part of the connecting portion 6C is shown in FIG. The mounting body 2 is bent along 6g so that the connecting portion 6D is added to the outer surface of the wall portion 2D of the mounting body 2 as shown in FIG.
And the connection portion 6D is used as the other external connection electrode of the light emitting device C. Therefore, the wall portion 2 of the mounting body 2
On the outer surface side of D, a connection electrode 5D and a connection electrode 6D as the light emitting device C are formed separately from each other in the left and right directions. Although the lead frames 5 and 6 are not bent in FIGS. 1 and 2, the lead frames 5 and 6 are used in a bent shape as shown in FIG. 3 in an actual structure. 2 shows a state before the lead frames 5 and 6 are bent.

The fixed portion 5A of the lead frame 5
Is sized to occupy most of the left side of the bottom portion 2A from the center portion of the bottom portion 2A as shown in FIGS. 1 and 2, and in the lead frame 6, the tip portion of the connecting portion 6B is narrower than the previous fixing portion 5A. It is arranged at a position slightly protruding from the wall 2C side,
The leading end of the lead frame 5 and the leading end of the lead frame 6 are arranged adjacent to each other on the bottom portion 2A in a state of being separated from each other. Further, the mounting body 2 is formed of a resin integrally molded product as described later. In this embodiment, the resin is integrally molded around the lead frames 5 and 6 so that It is formed integrally. Further, since the fixing portion side of the lead frame 5 is inserted into the groove portion 2G of the mounting body 2, the fixing portion 5A of the lead frame 5 is arranged so as to be flush with the upper surface of the mounting body bottom portion 2A. Since the connecting portion 6B of the lead frame 6 is inserted into the groove portion 2H of the
B is arranged so as to be flush with the upper surface of the mounting body bottom portion 2A, and the upper surface of the bottom portion 2A of the mounting body 2 is located between the lead frames 5 and 6.

Next, on the fixed portion 5A of the lead frame 5, a lower electrode (layer) 14 on the negative electrode side, which will be described later, having a chip-shaped light emitting element 1 made of a semiconductor substrate such as ZnSe formed at the bottom thereof is formed. Fixed by die bonding via
A lead wire 8 is connected by wire bonding to an after-mentioned upper electrode (layer) 13 on the positive electrode side formed on the light emitting element 1, and the lead wire 8 is connected to the lead frame 6.
Is connected to the connecting portion 6B. Here, the light emitting element 1 is fixed on the fixing portion 5A of the lead frame 5 by die bonding. The light emitting element 1 is slightly left from the center of the bottom portion 2A as shown in FIG. 1, that is, FIG. Is fixed to the left side wall portion 2E side of the lead frame 6, while the connecting portion of the lead wire 8 of the lead frame 6 is the bottom portion 2 shown in FIGS.
The central portion of the right half area of A, in other words, FIG. 1 and FIG.
Is formed at a position slightly apart from the right side wall portion 2C.

The lead wire 8 is fixed to the tip of the connecting portion 6B by wire bonding at a position slightly apart from the wall portion 2C as shown in FIG. 1 in the light emitting device C of this embodiment. This is because, in the case of a minute component having a width of about 2 mm and a length of about 1 mm, a margin for the movement width of the wire bonding device is required when the wire bonding device wire bonds the lead wire to the upper surface of the connecting portion 6B.
Further, the light emitting element 1 is attached to the wall portion 2E side (left side in FIG. 1) of the bottom portion 2A of the attachment body 2 with respect to the center portion thereof.
Generally, in order to connect by wire bonding, it is necessary to provide a suitable curve so as not to bend the lead wire 8 so that the lead wire 8 can be connected. Lead wire 8 to the tip
Considering that one end of the lead wire 8 is connected, the fixing portion 5A of the lead frame 5 needs to be arranged at a position where the other end of the lead wire 8 can be connected by wire bonding, and a little apart from the tip end of the lead frame 6. Is.
The light emitting element 1 and the wall portion 2E are spaced apart from each other because the light emitting element 1 is held by a robot hand for die bonding, a jig for holding, or the like, and is fixed to the fixing portion 5A.
This is because a space for moving the robot hand or the gripping jig is needed so that the robot hand or the gripping jig does not interfere with the wall portion 2E when die bonding is performed.

Due to the mutual restrictions on the wire bonding and the handling of the light emitting element 1, the position of the fixing portion 5A, the die bonding position of the light emitting element 1, and the lead wire 8 are provided.
Although the wire bonding positions of No. 1 are determined as shown in FIG. 1, the mounting positions of these are not limited in the present invention. Further, since the inclined surface 2F is formed on the wall portion 2C and the wall portion 2E, the width (opening width) on the upper end portion (tip portion) side of the wall portion 2C, 2E is the base end portion of the wall portion 2C, 2E. Since the width is larger than the width (opening width) on the (bottom) side, a space or margin when the light emitting element 1 is gripped and mounted on the bottom 2A by the tip of the previous robot hand or gripping jig. The cost can be widened, and the robot hand or the gripping jig can be easily moved.

Next, the bottom portion 2A and the wall portions 2B, 2 of the mounting body 2
A transparent resin material such as a transparent resin is filled in a region surrounded by C, 2D, and 2E so as to cover the inside of these wall portions, the light emitting element 1, the lead wire 8 and the like to form a transparent resin layer. The lens portion 9 is formed by processing the upper portion into a convex curved surface. When the lens portion 9 is formed, the bottom portion 2A of the mounting body 2 and the wall portions 2B, 2C, 2D, 2E.
After the resin is filled so as to cover the area surrounded by, a transparent lens member may be attached on the resin as a separate body, or the bottom 2A and the walls 2B, 2C of the mounting body 2 may be formed.
In addition to the region surrounded by 2D and 2E, a transparent resin material may be filled up to the upper side of the region, and the resin layer may be hardened by heat treatment such as curing and then polished to form the lens unit 9. Alternatively, a method may be used in which a lens body made of a resin material equivalent to the filled resin is attached as a separate body, and the filled resin and the lens body are integrated by heat treatment during curing. Further, a light reflecting layer (light reflecting portion) 2J is formed on each of the inclined surfaces 2F of the wall portions 2C and 2E of the mounting body 2.
These light reflecting layers 2J are coated with light reflecting paints, light reflecting particles on the inclined surfaces of the walls 2C and 2E, or are transferred by a manufacturing method described later. And the like.

The light emitting device 1 is II-VI of the periodic table.
ZnSe type semiconductors widely known as group compound semiconductors, for example, p ⁺ -GaA as shown in the sectional structure of FIG.
s substrate or p ⁺ -ZnSe substrate 10, p-ZnSe layer 11 and upper electrode (layer) 13 sequentially laminated thereon, and lower electrode (layer) laminated on the lower surface side of the previous substrate 10.
And the like are used. A typical structure of the light emitting device 1 used here is the semiconductor device having the above structure, but other generally known LEs are also available.
It is needless to say that a light emitting element having a different structure from the structure shown in FIG. 6 as the D light emitting element or other light emitting element may be appropriately used as the light emitting element of the present invention.

In the light emitting device C configured as described above, light can be emitted from the light emitting element 1 by applying a voltage to the light emitting element 1 via the external connection electrodes 5D and 6D. The light emitting element 1 of this form emits light from the light emitting element 1 in all directions around the light emitting element 1. That is, the light emitting element 1 emits light in a direction away from the bottom portion 2A of the mounting body 2 at a right angle, and also in a direction parallel to the bottom portion 2A, that is, sideways light, obliquely above the bottom portion 2A, or The light directed downward and further toward the bottom portion 2A is also emitted.

A part of these lights is a light reflection layer 2J having inclined walls 2C and 2E provided around the light emitting element 1.
Reflects and guides light in a direction perpendicular to the bottom 2A or in a direction close to the bottom 2A. Therefore, the light emitting device C according to this embodiment is closer to or perpendicular to the bottom 2A than the conventional light emitting device. , Can emit stronger light. Further, when the light reflection layer 2J is made of metal powder or the like, light can be strongly reflected by the metal powder having high reflectance, so that a brighter light emitting device C can be obtained. Further, since the lens portion 9 is provided outside the light emitting element 1 in the present embodiment, a stronger light is emitted in the direction orthogonal to the bottom portion 2A or in a direction closer to the bottom portion 2A due to the condensing action of the lens portion as compared with the conventional light emitting device. Can be emitted, and a brighter light emitting device C can be provided.

Next, a suitable light emitting direction in the present embodiment is shown by an arrow S in FIG. 3, and the connecting electrodes 5 as the light emitting device C are provided on the side and the side with respect to the emitting direction S.
Since D and 6D are provided, a side electrode structure having an electrode on the side of the light emission direction can be adopted. This side electrode structure contributes to improvement in workability of wiring work for connecting the power source to the light emitting device C when the mounting body 2 is a minute component such as a few mm square. Further, in the above description, the connection electrodes 5D and 6D are on the tip end side of the lead frames 5 and 6, but the connection portion 5B of the lead frame 5 located outside the wall portion 2E may be the electrode portion. Wall 2
The connection portion 6B of the lead frame 6 located outside C may be used as the electrode portion. That is, in the light emitting device C according to the present embodiment, the positioning of the connection electrodes is performed on the wall 2D side and the wall 2C, 2C.
It is configured to be easy to select in either direction on the E side.

Next, in the light emitting device C of the present embodiment,
A reflective layer may be formed on the upper surface of the bottom portion 2A of the mounting body 2. In that case, it is necessary to form a reflective layer on the upper surface of the bottom portion 2A of the mounting body 2 so that the tip portions of the lead frames 5 and 6 are electrically connected to each other and are not short-circuited. Therefore, when the reflective layer is composed of the electrically insulating fluorescent paint, the reflective layer of the fluorescent paint can be formed on the entire upper surface of the bottom portion 2A, and when the reflective layer is composed of the light-reflective metal powder, the lead layer is formed. The reflection layer is formed so as to be separated from the tip end sides of the lead frames 5 and 6 so that the frames 5 and 6 are not short-circuited. By forming the reflective layer on the bottom portion 2A, the light emitted from the light emitting element 1 to the bottom portion 2A side can be reflected and effectively used in the emission direction S, and the light emitted from the light emitting device C can be used. Can be made stronger.

Next, in the light emitting device C of the present embodiment,
A reflective layer may be formed on the tip surfaces 2K of the walls 2B, 2C, 2D, 2E. In the case of this configuration, the walls 2B, 2
The brightness of the light emitting device C can be further increased by effectively utilizing the reflective layers of the tip surfaces 2K of C, 2D, and 2E.

Next, an example of a method of manufacturing the light emitting device C having the structure described in the above embodiment will be described below. In order to manufacture the light emitting device C of the above-described form, first, the resin molding die 19 is prepared. The mold 19 is composed of, for example, a lower mold 20 and an upper mold 21, as shown in FIG.
A cavity 20A capable of molding the bottom portion 2A of the previous mounting body 2 is formed in the upper portion of the lower mold 20, and the wall portions 2B, 2C, 2D, 2E of the previous mounting body 2 can be molded in the lower portion of the upper mold 21. A cavity 21A is formed, and in the state shown in FIG. 7 in which the lower die 20 and the upper die 21 are combined, a gap (that allows the lead frames 5 and 6 to be sandwiched at the boundary between the lower die 20 and the upper die 21 ( It is preferable that the space D is formed. In the mold 19, a slope portion 23 is formed so as to correspond to a portion where the walls 2C and 2E can be molded.

In order to manufacture the light emitting device C by using the lower mold 20 and the upper mold 21, the lower mold 20 and the upper mold 21 are first sandwiched with the lead frames 5 and 6 as shown in FIG. The mold 21 is fitted and the molding cavity 2 is provided between the two.
0A and 20B are formed. Here, in order to facilitate the mold release work of the molded body after molding, it is preferable to attach the release sheet 22 to the lower surface side of the cavity 21A of the upper mold 21. After this, this molding cavity 20A,
A resin such as a white epoxy resin is injected into 21A from an injection hole (not shown in the drawing) of the mold 19, and the injected resin is molded into the molding cavities 20A, 21 around the lead frames 5, 6.
Harden at A and 21A.

Once the resin in the mold has hardened, the lower mold 20
The upper die 21 and the upper die 21 are separated, and the mounting body 2 with a lead frame shown in FIG. 8 is released from the die. In this releasing operation, the release sheet 22 is arranged between the mounting body 2 and the inner surface of the mold, so that the mounting body 2 can be easily removed from the mold 19. Then, after the mounting body 2 is released from the mold 19, on the inclined surfaces 2F, 2F of the wall portions 2C, 2E of the mounting body 2,
Light-reflecting metal powder such as silver powder, gold powder, aluminum powder or fluorescent paint is adhered by a method such as a spraying method or a coating method to form the reflecting layer 2J shown in FIG. Also here
In addition to forming the reflective layer 2J on the inclined surfaces 2F, 2F,
Applying light-reflecting metal powder such as silver powder, gold powder, aluminum powder or fluorescent paint to the upper surface of the bottom portion 2A of the mounting body 2 by a method such as a spraying method so that the lead frames 5 and 6 are not short-circuited. The reflective layer 2L may be formed as shown. Further, the tip surfaces 2K of the wall portions 2B, 2C, 2D, 2E of the mounting body 2 are coated with a light-reflecting metal powder such as silver powder, gold powder, aluminum powder or fluorescent paint by a spraying method or the like. The reflective layer 2M may be separately formed on 2K. Further, in order to improve the light reflectivity of the lead frames 5 and 6 themselves, the lead frames 5 and 6 are coated with a light-reflecting metal powder such as silver powder or gold powder or a fluorescent paint by a method such as a spraying method. A reflective layer may be formed on the upper surface, or the lead frames 5 and 6 themselves may be formed in advance with a metal having high light reflectivity.

If the reflective layer 2J is formed on the mounting body 2,
As shown in FIG. 10A, the light emitting element 1 is bonded to the fixed portion 5A of the lead frame 5 by die bonding, the lower electrode 14 of the light emitting element 1 is electrically connected to the mounting portion 5A of the lead frame 5, and then wire bonding is performed. Then, the lead wire 8 electrically connects the upper electrode 13 of the light emitting element 1 and the lead frame 6.

Next, the bottom portion 2A and the wall portions 2B, 2 of the mounting body 2
A transparent resin material such as potting resin is filled in a portion surrounded by C, 2D, and 2E, and the transparent resin material is heat-cured and then the upper portion thereof is polished to form a convex curved surface. The lens portion 9 shown in 10A is formed. It is preferable that the curved surface shape of the lens portion 9 has a relationship described in other embodiments described later. In addition, when forming the lens portion 9, as shown in FIG.
After filling the portion surrounded by the bottom portion 2A and the wall portions 2B, 2C, 2D, 2E with a transparent resin material such as potting resin so that the upper surface of the resin material becomes a flat surface, the transparent resin layer 9A is formed. Alternatively, the lens portion 9C may be formed by a method in which the processed transparent resin lens member 9B is placed in a lens mold and heat-treated to bond the two.

Incidentally, after the mounting portion 2 with the lead frames 5, 6 is released from the molds 20, 21, until the lens portion 9 is formed or after the lens portion 9 is formed. A connecting electrode as shown in FIG. 3 is formed by bending the lead frames 5 and 6 at any stage to bend part of the lead frames 5 and 6 protruding outside the molded body along with the molded body. The parts 5D and 6D can be formed.

In the present embodiment, the method of bending the lead frames 5 and 6 after integrally molding the mounting body 2 to the lead frames 5 and 6 is adopted. However, by devising the shape of the mold, it is partially bent in advance. It is also possible to configure the lead frames 5 and 6 in the open state to be attached to the mold, and to attach the lead frames 5 and 6 in a partially bent state to the die and then to integrate them by resin molding. By performing the work in each step described above, the light emitting device C having the structure shown in FIG.
Can be obtained.

If the light emitting device C is manufactured by the manufacturing method described above, the lead frames 5 and 6 can be easily integrated with the mounting body 2 to manufacture the light emitting device C. Further, since the mounting body 2 is molded by injecting a resin around the lead frames 5 and 6, the lead frames 5 and 6 are mounted on the mounting body 2.
It can be firmly fixed by being closely attached so as to be embedded in. Next, light is emitted from the light emitting element 1 in all directions around the light emitting element 1, but the light emitted from the light emitting element 1 in the left and right lateral directions is reflected upward by the reflection layer 2H of the inclined surfaces 2D of the side wall portions 2C and 2C. As a result, the light emitted from the light emitting element 1 can be guided in a desired direction with higher efficiency than the conventional light emitting device because the light is emitted from the light emitting element 1 in the direction perpendicular to the bottom 2A of the mounting body 2. Therefore, the light emitting device C of the present embodiment can improve the light emission efficiency and can provide a brighter light emitting device C.

Also, in the method of manufacturing by integrally molding the lead frames 5, 6 and the mounting body 2 by resin molding described above, unlike the conventional structure, the lead frames 5, 6 and the mounting body are integrally molded. Since the two can be easily integrated and a state in which the bonding strength between them is high can be obtained, the light emitting device C can be formed extremely easily compared with the case where the bonding is performed as in the conventional structure. can do.

In the light emitting device C of this embodiment, particularly when it is necessary to focus and irradiate light in a specific direction, the angle of the inclined surface 2F of the mounting body 2 is adjusted to direct the light in the desired direction. It is desirable to configure so that more light can be condensed and irradiated. Further, when the lens portion 9 is provided, it is desirable that the radius of curvature of the lens portion 9 be adjusted so that more light can be condensed and emitted in a target direction. Further, although the center of the radius of curvature of the lens portion 9 is arranged on the center side of the mounting body 2 in the previous embodiment, the center of the radius of curvature of the lens portion 9 is located on the wall portion 2E side, that is, the mounting of the light emitting element 1. Of course, it may be provided so as to be offset to one side.

FIG. 11 shows an embodiment in which the inclined surfaces of the walls 2C and 2E are processed into a curved surface in the light emitting device C described in the first embodiment. The mounting body 52 shown in FIG. 11 is almost the same as the structure of the first embodiment and has a bottom portion 52A and walls 52C and 52E, but the surface of the walls 52C and 52E on the light emitting element 1 side is curved. It is composed of inclined surfaces. FIG. 12 is a view for schematically explaining the mounting position and the shape of the inclined surface with respect to the mounting body 52 having the same structure as the mounting body 2 of the light emitting element 1 described in the first embodiment. As shown in FIG. 12, the bottom portion 52A and the wall portions 52C and 52E of the mounting body 52 are attached.
And the inclined surface 5 of the inner surface of the wall portion 52C.
When 2F has a curved surface and is formed in a quadratic curve in cross section, it is preferable to have a shape that meets the following formula in consideration of the case where the upper surface of the lens portion 59 is processed into a curved surface.

As shown in FIG. 12, the light emitting element 1 is provided with a bottom portion 5.
Assuming that the light emitting element 1 is installed on the upper surface of 2A, the skirt portion of the inclined surface 52F of the wall 52C (the inclined surface 52
X is the distance from the point where F connects to the upper surface of bottom 52A)
Assuming that the horizontal distance from the center of the light emitting element 1 to the upper end of the inclined surface 52F of the wall 52C is X1, the wall height from the upper surface of the bottom 52A to the upper end of the wall 52C is H.
_It is assumed that _wall , the thickness of the lens portion from the upper surface of the bottom portion 52A to the central portion of the upper end of the lens portion 59 is H1, the height of the light emitting element 1 is H, and the curvature of the lens portion is R _lens. In this case, it is preferable to set each value so as to satisfy the relationships of the following expressions (1), (2), and (3).

First, the inclined surface 52 on the inner surface of the wall 52C.
It is preferable that the following formula (1) is satisfied when R _wall is the inclined state when F has a quadratic curve in section. | R _wall − {(X1−X0) ² + H _wall ² } / 2 (X1−X0) | <0.5 (1) Expression Also, the height H _wall of the wall portion 52C and the height of the light emitting element 1 are: It is preferable that the thickness (thickness) H satisfies the following expression (2). | {(H _wall -H) / (X1-X)}-1/2 ^1/2 | <0.4 equation (2) When the curvature of the lens portion is R _lens , the following (3) It is preferable to satisfy the relationship of the formula. _{│R lens} -{(H1-H _wall ) ² + X12 ² } / 2 (H1-H _wall ) │ <0.5 ... (3)

Actually, as shown in FIG. 11, the light emitting element 1 is provided at a position slightly displaced from the center of the upper surface of the bottom portion 52A of the mounting body 52, and the wall portion 52C on the right side of the light emitting element 1 is provided.
Is different from the distance from the light emitting element 1 to the left side wall portion 52E, the height of the right side wall portion 52C and the shape of the inclined surface 2F, and the height of the left side wall portion 2E and the inclined surface 2F.
It is preferable to increase the light reflection efficiency by forming the shape and the shape so as to be different from each other by using the above formulas (1) to (3).

[0043]

EXAMPLE A box-shaped mounting body made of white epoxy resin having a shape shown in FIG. 12 was molded, and a ZnSe type semiconductor light emitting device having a sectional structure shown in FIG. A transparent resin lens portion was formed so as to cover the periphery of the light emitting element with such wiring and a light emitting device was manufactured. When a voltage of 2.6 V is applied to the light emitting element to cause it to emit light, the directivity angle (light beam spreading angle) of the light emitted from the light emitting element and emitted from the lens unit is measured under the following conditions. Shown in 1. Here, the light emitting element 1
From the center of the light emitting element 1 to the skirt portion of the inclined surface 52F of the wall 52C (the portion where the inclined surface 52F is connected to the upper surface of the bottom 52A) is X0.
The horizontal distance to the upper end of the inclined surface 52F of C is X1,
X is the distance from the center of the light emitting element 1 to the end of the light emitting element 1.
And the wall height from the upper surface of the bottom portion 52A to the upper end portion of the wall portion 52C is H _wall, and from the upper surface of the bottom portion 52A to the lens portion 5
The height of the wall to the center of the upper end of 9 is H1, the height of the light emitting element 1 is H, the curvature of the lens portion is R _lens , and the inclined surface 5
The radius of curvature of 2F is R _wall, and among these values, X is fixed to 0.2, H is set to 0.2, X0 is set to 0.65, X1 is set to 1.05, and other values are set. In the case of setting as shown in Table 1, the obtained directivity angle is measured.

[0044]

[Table 1]

As shown in Table 1, in this embodiment, a light beam orientation angle of less than 100 ° was judged to be acceptable. As is clear from the results shown in Table 1, only the radius of curvature R _wall is 0.40 to 1.6.
When it is increased / decreased in the range of 0 and is within the range of the formula (1), the directivity angle of the light flux is less than 100 °, specifically 50 to 8
It can be set in the range of 4 °, and it can be judged that it is more preferable in terms of condensing light. As is clear from the results shown in Table 1, when the H _wall , the radius of curvature R _wall, and the _wall height are increased or decreased within the range of the formula (2), the luminous flux directivity angle is less than 100 °, Specifically, 50 to 8
It can be set in the range of 9 °, and it can be judged that it is more preferable in terms of focusing. Table as 1 to indicate apparent from the results, the curvature R _lens-- lens portion H _wall and the curvature radius R _wall and wall height as constant H1 2.36
Up to 3.36 and within the range of the formula (3), the light beam directivity angle is less than 100 °, specifically 50 to
It can be set in the range of 85 °, and it can be judged that it is preferable in terms of collecting light.

[0046]

As described above, the present invention has a structure in which the inclined surface is provided on the wall portion of the mounting body provided with the light emitting element, so that a part of the light emitted laterally from the light emitting element is covered by the wall. Since the light can be reflected by the inclined surface of the portion and emitted, the light emitted from the light emitting element in various directions can be condensed and emitted in one direction as much as possible. Therefore, the brightness of the light emitting device can be improved. Further, if the light reflecting portion is formed on the inclined surface, the light can be strongly reflected by the light reflecting portion, so that the light emitted from the light emitting element in various directions is condensed in one direction, and The brightness can be further improved.

According to the light emitting device of the present invention, the distance between the front ends of the opposite wall portions is made wider than the distance between the base end sides of the opposite wall portions, and the distance between the wall portions provided on the bottom portion is opposite. Since the opening on the upper side is wider than the opening on the lower side,
When the light emitting element is mounted on the bottom part, a jig of the mounting device, a robot hand, etc. are easily inserted between the walls, and the mountability when mounting the light emitting element on the bottom part is improved. Especially when the light emitting device is a minute part such as a few mm square, the space between the walls is also in the unit of several mm. Therefore, the larger the space on the inlet side between the walls is the better for mounting the light emitting element. Becomes

In the light emitting device of the present invention, in the above-described structure, since the light reflecting portion is formed on the bottom portion of the mounting body, even if the light is emitted from the light emitting element toward the bottom portion of the mounting body, The light can be reflected by the light reflecting portion on the bottom of the mounting body, light can be emitted in a direction away from the bottom of the mounting body, and the brightness of the light emitting device can be further improved.

In the light emitting device of the present invention, the light reflecting portion is made of an aggregate of light reflecting metal powder such as silver powder, gold powder, aluminum powder or a fluorescent paint, or the light reflecting portion is an aluminum reflecting layer or the like. Of the light reflection layer. With the light reflecting portion made of these metal powders or the light reflecting portion made of a light reflecting layer such as an aluminum reflecting layer, it is possible to reflect light with a high reflectance and further improve the brightness. Even if the light reflecting portion is made of fluorescent paint, the brightness as a light emitting device can be improved.

The light emitting device of the present invention has a structure in which a light emitting element is installed on the bottom of the mounting body, the inclined surface of the wall portion is formed in a curved surface, and the wall portion extends from the central portion of the light emitting element. When the horizontal distance to the upper end of the inclined surface is X1, the wall height from the upper surface of the bottom to the upper end of the wall is H _wall, and the inclined state of the inclined surface is R _wall , The luminous efficiency can also be increased by satisfying the relationship of the following formula. _{│R wall} -{(X1-X0) ² + H _wall ² } / 2 (X1-X
0) | <0.5

The light emitting device of the present invention has a structure in which a light emitting element is installed on the bottom of the mounting body, the inclined surface of the wall is formed in a curved shape, and the upper surface of the bottom to the upper end of the wall is formed. Assuming that the wall height up to is H _wall and the height of the light emitting element is H, the light emission efficiency can be increased by satisfying the relationship of the following equation. | {(H _wall -H) / (X1-X)}-1/2 ^1/2 | <
0.4

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a state in which a lead frame is straightened in a first embodiment of a light emitting device according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a state in which the lead frame is stretched in the first embodiment of the light emitting device according to the present invention.

FIG. 3 is a perspective view showing a bent state of the lead frame in the first embodiment of the light emitting device according to the present invention.

FIG. 4 is a plan view showing an example of one lead frame applied to the light emitting device of the first embodiment.

FIG. 5 is a plan view showing an example of the other lead frame applied to the light emitting device of the first embodiment.

FIG. 6 is a cross-sectional view showing an example of a light emitting element included in the light emitting device of the first embodiment.

FIG. 7 is a cross-sectional view showing an example of a mold used for manufacturing the light emitting device of the first embodiment according to the present invention.

8 is a cross-sectional view showing a state where the lead frame and the mounting body are integrally molded by the mold shown in FIG.

9 is a cross-sectional view showing a state in which a reflective layer is formed on a part of the lead frame and the mounting body obtained as shown in FIG.

10 shows a state in which a lens portion made of a transparent material is formed on the lead frame and the mounting body shown in FIG. 9, and FIG. 10 (A) shows a structure in which the lens portion is integrally molded. A cross-sectional view, FIG. 10B is a cross-sectional view showing a structure in which the lens portion is composed of two members.

FIG. 11 is a cross-sectional view showing an embodiment in which the inclined surface of the wall portion of the light emitting device according to the present invention is a curved surface.

FIG. 12 is a diagram showing the height of the wall portion, the shape of the curved inclined surface, and the positional relationship of the light emitting device in the light emitting device of the same embodiment.

FIG. 13 is a sectional view showing an example of a conventional light emitting device.

FIG. 14 is a cross-sectional view showing another example of a conventional light emitting device.

[Explanation of symbols]

C light emitting device 1 Light emitting element 2 mounting 2A bottom 2B, 2C, 2D, 2E walls 2F slope 2J Light reflection layer (light reflection part) 2K tip surface 2L, 2M Light reflection layer (light reflection part) 5,6 lead frame 5D, 6D external connection electrode 8 lead wires 13 Top electrode (layer) 14 Bottom electrode (layer)

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5F041 AA03 AA06 CA42 DA12 DA16                       DA25 DA26 DA44 DA46 DA57                       DA58 DB03 DB09 DC10 EE17                       EE23

Claims (9)

[Claims] 1. A positive electrode side negative electrode side lead frame is attached to an attachment body having a bottom portion and a wall portion separately from each other so as to contact the bottom portion, and one light emitting element is attached to one lead frame. And one electrode of the light emitting element is electrically connected, and the other electrode of the light emitting element is electrically connected to the other lead frame, while the surface of the wall portion on the light emitting element side is A light-emitting device comprising an inclined surface, and a light-reflecting portion that reflects light emitted from the light-emitting element is formed on the inclined surface. 2. A wall portion is formed at least at two opposite locations on a peripheral edge portion of the bottom portion, and an inclined surface formed on the wall portion causes a distance between tip ends of the opposite wall portions to face each other at the opposite wall. The light emitting device according to claim 1, wherein the light emitting device is wider than a space between the base ends of the parts. 3. The light emitting device according to claim 1, wherein a light reflecting portion is formed on a bottom portion of the mounting body. 4. The light emitting device according to claim 1, wherein a light reflecting portion is formed on a front end surface of a wall portion of the mounting body. 5. The light emission according to claim 1, wherein the light reflecting portion is made of an aggregate of light reflecting metal powder such as silver powder, gold powder, aluminum powder or a fluorescent paint. apparatus. 6. The light reflecting portion is formed of a light reflecting layer such as an aluminum reflecting layer.
The light emitting device according to any one of 1. 7. A bottom electrode is formed on the light emitting device, the bottom electrode is fixed on the one lead frame, and another electrode formed on the top of the light emitting device is connected to the other of the other via a lead wire. The light emitting device according to claim 1, wherein the light emitting device is connected to a lead frame. 8. A structure in which a light emitting element is installed on a bottom portion of the mounting body, the inclined surface of the wall portion is formed in a curved surface, and an upper end of the inclined surface of the wall portion is formed from a central portion of the light emitting element. When the horizontal distance to the section is assumed to be X1, the wall height from the upper surface of the bottom to the upper end of the _wall is assumed to be H _wall, and the inclined state of the inclined surface is R _wall , the relation of the following equation 8. The light emitting device according to claim 1, wherein _{│R wall} -{(X1-X0) ² + H _wall ² } / 2 (X1-X
0) | <0.5 9. A structure in which a light emitting element is installed on a bottom portion of the mounting body, the inclined surface of the wall portion is formed into a curved surface, and a wall height from an upper surface of the bottom portion to an upper end portion of the wall portion. To H
_The light emitting device according to any one of claims 1 to 7, wherein when the _wall is assumed and the height of the light emitting element is assumed to be H, the relationship of the following formula is satisfied. | {(H _wall -H) / (X1-X)}-1/2 ^1/2 | <
0.4