JP3201791B2 - Optical output device mounting structure and mounting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of an optical output device and a mounting method thereof, and more particularly, to a mounting structure of an optical output device comprising a wiring board, a plurality of light emitting elements and a control circuit element, and a mounting method thereof. About.

[0002]

2. Description of the Related Art As a conventional mounting structure of this type of optical output device, there is, for example, a wire bonding structure as shown in FIG. In FIG. 4, reference numeral 1 denotes a wiring board, on which an electrode 1a made of a conductive material is provided. On the substrate 1, a light emitting element 2 composed of an LED having a display section 2a provided on the upper surface and a drive LSI chip 3 are mounted by an adhesive, respectively. These light emitting element 2 and the chip 3 are each made of a conductive material. Are connected by wires 4 made of a conductive material such as Au via electrodes 2b and 3a made of Au. The electrode 1a
And the electrode 3b provided on the chip 3 are connected by a wire 5 made of a conductive material such as Au.

The mounting structure of the optical output device having such a configuration is such that after an external input signal is transmitted to the chip 3 via the electrode 1a and the wire 5, the light emitting element 2 is transmitted from the chip 3 via the wire 4. , The light emitting element 2 emits and extinguishes light. However, in this light output device mounting structure, since the light emitting element 2 and the chip 3 are mounted on the wiring board 1 with the wiring 4 separated from each other, the light emitting dot density of the light emitting element 2 is large. That is, when a large number of light emitting elements 2 are mounted on the wiring board 1,
Since the connection pitch of the electrodes 2b and 3a becomes small, a problem occurs that the light emitting element 2 and the chip 3 cannot be connected by the wire 4.

As a mounting structure for solving such a problem, for example, there is a flip chip structure as shown in FIG. This is achieved by a known face-down method.
Light emitting element 11 composed of ED and drive LSI chip 12
The wirings 11a, 11b, 12a, and 12b are directly connected to the wirings 14a to 14c of the substrate 14 via the bumps 13a to 13d, so that the light emitting element 11 and the drive LSI chip 12 are connected to the substrate 14
Has been implemented.

The light emitting element 11 and the drive L
Since the SI chip 12 is directly connected to the substrate,
The connection pitch between the drive LSI chip 11 and the drive LSI chip 12 can be reduced, and the light emitting dot density can be increased by mounting a large number of light emitting elements 11 on the substrate 14.

[0006]

However, in such a conventional mounting structure of an optical output device, the light emitting element 11 and the drive LSI chip 12 are not connected to the bumps 13a to 13a.
Since it is mounted on the substrate 14 via the line d, there are the following problems. (1) Since the light emitting element 11 and the chip 12 are mounted on the substrate 14 by the bumps 13 to 13d, the connection process of the light output device is increased, so that not only the manufacturing is complicated, but also the manufacturing cost is increased. . In addition to this, the light emitting element 11
Since the components and the like are mounted on the substrate 14 by the face-down method, if the arrangement of the substrate 14 is fine and complicated, a high mounting technology is required, so that the yield is deteriorated and the productivity is deteriorated. (2) The light emitting element 11 and the like are substrated by a face-down method.
When the heating element 11 having a large power is used for mounting on the substrate 14, since the heat is radiated from the back side of the element 11 and not radiated from the substrate 11, the heat radiation direction of the heating element 11 is limited. As a result, it is impossible to use the light emitting element 11 having a large power while sufficiently coping with the heat radiation. (3) Since the light emitting element 11 and the chip 12 are mounted on the wiring board 14 so as to be separated from each other, the size of the board 14 is inevitably increased. (4) Since the light emitting element 11 and the chip 12 are mounted on the substrate 14 by the bumps 13 to 13d, the light emitting element 11 and the
The bumps 13a to 13d are distorted due to the difference in thermal expansion coefficient between the bumps 13a to 13d, and the height of the light emitting element 11 and the like in the direction of the arrow Z varies, thereby deteriorating the reliability of the device.

Therefore, the present invention can easily mount a light emitting element and a control circuit element on a substrate without increasing the size of the substrate, and can prevent the yield from deteriorating. It is an object of the present invention to provide a mounting structure and a mounting method of a light output device which can improve workability, productivity and reduce manufacturing cost, and have good heat dissipation.

[0008]

According to the first aspect of the present invention,
In order to achieve the above object, a wiring board and mounting on the board
And an edge light-emitting element having a light-emitting portion on its side.
A plurality of light emitting elements, and a plurality of control circuit elements mounted on the wiring board and provided for each light emitting element to control the light emitting element, the light output device comprising: And one of the light emitting element and the control circuit element is mounted such that the opposite side faces the other, and the other light emitting element and the control circuit element are mounted on one of the light emitting element and the control circuit element. Face-down bonding is performed on one of the light emitting element and the control circuit element via a bump so as to face the electrode surface side .
The light emitting element mounted on the wiring board is mounted, and one of the light emitting element and the control circuit element mounted on the wiring board is formed larger than the other of the light emitting element and the control circuit element. It is characterized by doing.

According to a second aspect of the present invention, in order to achieve the above object, when the other one of the light emitting element and the control circuit element is mounted on one of the light emitting element and the control circuit element In addition, the mounting is performed with reference to the alignment mark provided on one of the light emitting element and the control circuit element. According to a third aspect of the present invention, in order to achieve the above object, a plurality of light emitting elements and a plurality of control circuit elements, each of which is in contact with a back surface on the other side of the plurality of light emitting elements and the control circuit elements, are arranged in blocks. A light-emitting element and a control device are provided between the light-emitting element and the control circuit element by pressing one of the light-emitting element and the control circuit element through the other of the light-emitting element and the control circuit element. It is characterized in that the circuit element is held for each block, and that the light emitting element and the control circuit element are radiated by the pressing member.

[0010] invention 請 Motomeko 4 wherein, in order to achieve the above object, one of the light emitting element and the control circuit element is characterized in that it is mounted on the plane of the direct wiring board.

According to a fifth aspect of the present invention, in order to achieve the above object, one of the light emitting element and the control circuit element is mounted on a wiring board via an intervening object.

[0012]

According to the first aspect of the present invention, the light emitting element and the control circuit element are face down on the wiring board via the bump.
They are mounted in layers by bonding . Therefore, since both the light emitting element and the control circuit element are attached to the wiring board in a state where the light emitting element and the control circuit element are connected in advance, complicated wiring on the wiring board becomes unnecessary, and the number of steps for connecting the light emitting element and the like is reduced. For this reason, the yield of the device is improved, and both elements are easily mounted on the wiring board, so that the workability and productivity of the manufacturing operation are improved, and the manufacturing cost is reduced. In addition, since the two elements are not arranged separately on the wiring board, the size of the wiring board can be reduced. Further, since one of the light emitting element and the control circuit element mounted on the wiring board is formed larger than the other, a plurality of one of the light emitting element and the control circuit element are arranged close to the wiring board. And the other of the light emitting element and the control circuit element is necessarily mounted thereon. As a result, a large number of light emitting elements are mounted on the wiring board, the light emitting dot density is increased, and a highly accurate light output device can be obtained. Also,
The light emitting element is an edge light emitting element having a light emitting part on a side surface part.
Therefore, the light emitting element and the control circuit element
Can be laminated, light emitting element and control circuit element lamination
Becomes easier.

According to the second aspect of the present invention, one of the light emitting element and the control circuit element is mounted on the element on one side with reference to the alignment mark provided on one of the light emitting element and the control circuit element. You. Therefore, one of the light emitting element and the control circuit element can be easily attached to the other with high accuracy. In the invention according to claim 3, a plurality of pressure members are provided on the back surface on the other side of any of the plurality of light emitting elements and the control circuit element so as to abut on each block of the plurality of light emitting elements and the control circuit element, The light emitting element and the control circuit element are held for each block between the wiring board and the wiring board by the pressing member. Therefore, the heating element and the control circuit element are electrically stably joined, and the pressing force of the heating element and the control circuit element is adjusted for each block, and is stably held on the wiring board. Also,
Since the heat radiation of the light emitting element and the control circuit element is performed by the pressing member, the heat generated in the heating element and the control circuit element is radiated from the back surfaces of the two elements via the wiring board and the pressing member, respectively. Therefore, a light-emitting element having high heat dissipation and high power is used.

[0014] In the invention 請 Motomeko 4, wherein either one of the light emitting element and the control circuit element is mounted on the plane of the direct wiring board. Accordingly, the height of the light emitting element and the control circuit element does not vary, and the two elements are held at a uniform height by the pressing member.

According to the fifth aspect of the present invention, one of the light emitting element and the control circuit element is mounted on the wiring board via an intervening object. Therefore, the height of the light emitting element and the control circuit element does not vary, and the pressing force of the pressing member is stably applied to the two elements, and the two elements are stabilized at a uniform height by the pressing member. Is held.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.
1 to 3 are views showing one embodiment of a mounting structure of a light output device according to the present invention and a method of manufacturing the same. First, the configuration will be described. In FIG. 1, reference numeral 21 denotes a wiring board, on which an electrode 21a made of a conductive material is provided. A light emitting element is provided on the plane of the wiring board 21a.
The light-emitting element 22 is provided with electrodes 22a to 22c made of a conductive material.
That is, the surface (back surface) of the light emitting element 22 opposite to the surface on which the electrodes 22 a to 22 c are provided faces the substrate 21. Also,
The light emitting element 21 has a light emitting section 22d on the side surface.

A drive LSI chip 23 as a control circuit element is provided above the light emitting element 22, and electrodes 23a and 23b made of a conductive material are provided on a lower surface of the chip 23. Further, the light emitting element 22 is formed larger than the chip 23, and the element 22 and the chip 23 are connected with respective electrodes 22a, 22b and 23a, 23b via bumps 24a, 24b made of a conductive material. . For this reason, the chip 23 is mounted on the light emitting element 22 by a so-called face-down method via the bumps 24a and 24b.

An alignment mark (not shown) is provided on the upper surface of the light emitting element 22 so that the chip 23
When it is mounted on 22, it is mounted based on the alignment mark. The electrode 21a and the electrode 22c are connected by a wire 25 made of a conductive material such as Au. The wire 25 transmits an external signal transmitted via the electrode 21a to the light emitting element 22 and the chip 23. ing. Therefore, the light emission and extinguishing of the light emitting element 22 are controlled by the chip 23.

A plurality of the light emitting elements 22 and the chip 23 are mounted on the wiring board 21 as shown in FIG. 2 (the wires 26 are omitted in FIG. 2). A plurality of radiators 26 as a pressing member are in contact with. Although only one radiator 26 is shown in FIG. 2, each radiator 26 is provided for each block of the plurality of light emitting elements 22 and the chip 23, and by pressing the light emitting element 22 via the chip 23, The light emitting element 22 and the chip 23 are held between the wiring board 21 and each block. The radiator 26 radiates the heat generated in the chip 23 to the outside, while the heat generated from the heating element 22 is radiated to the outside from the wiring board 21.

In this embodiment having such a configuration, the light emitting element 22 and the chip 23 are mounted on the wiring board 21 in an overlapping manner.
The heating element 22 and the chip 23 can be attached to the wiring board 21 in a state where they are connected via the
The above complicated wiring can be eliminated. For this reason,
The number of steps for connecting the light emitting elements 22 can be reduced, the device yield can be improved, and both elements can be easily mounted on the wiring board. As a result,
The workability and productivity of the device manufacturing operation can be improved, and the manufacturing cost can be reduced.

Further, since the heating element 22 and the chip 23 are not arranged on the wiring board 21 at a distance, the size of the wiring board 21 can be reduced. Further, since the light emitting element 22 mounted on the wiring board 21 is formed larger than the chip 23,
A plurality of light emitting elements 22 can be arranged close to each other on the wiring board 21, and the chip 23 can be mounted on the light emitting elements 22 inevitably. For this reason, a large number of the light emitting elements 22 can be mounted on the wiring board 21, and the light emitting dot density can be increased to obtain a highly accurate light output device.

Further, since the chip 23 is mounted on the light emitting element 22 with reference to the alignment mark provided on the upper surface of the light emitting element 22, the light emitting element 23 can be easily mounted on the chip 22 with high accuracy. . Further, on the back surface of the plurality of chips 23, there are provided a plurality of radiators 26 which are in contact with each block of the plurality of light emitting elements 22 and the chip 23. Is held for each block, so that the heating element 22 and the chip 23 can be electrically stably joined together, and the heating element
The pressing force of the chip 22 and the chip 23 can be adjusted for each block and can be stably held on the wiring board 21.

Since the radiator 26 radiates heat to the light emitting element 22 and the chip 23, heat generated in the heating element 22 and the chip 23 is transferred from the back surface of the heating element 22 and the chip 23 to the wiring board 21 and the radiator, respectively. Heat can be dissipated through 26. For this reason, the efficiency of heat radiation can be improved, and the light-emitting element 22 with high power can be used.

Further, since the light emitting element 22 is an edge light emitting element having the light emitting portion 22d on the side surface, the lamination of the light emitting element 22 and the chip 23 can be facilitated. Further, since the light emitting element 22 is directly mounted on the plane of the wiring board 21, the height of the light emitting element 22 and the chip 23 can be prevented from being varied, and the light emitting element 22 and the chip 23 can be dissipated. With 26, it can be held at a uniform height.
Therefore, the display element 22 and the chip 23 can be mounted on the bumps 24a and 24b without any special measures for adjusting the height of the display element 22 and the like.
Can be used only for electrical bonding.

In this embodiment, the light emitting element is
22 is mounted, and a chip 23 is mounted on the element 22.
A chip 23 may be mounted on the wiring board 21, and the light emitting element 22 may be mounted on the chip 23. In addition, the light emitting element 22
Is directly attached to the wiring board 21, but is not limited to this. As shown in FIG. 3, the light emitting element 22 is attached to the wiring board 21 through an intervening body composed of a UV curing adhesive 31 and a conductive spacer 32. Is also good. By doing so, it is possible to prevent variations in the height of the light emitting element 22 and the chip 23, and to stably apply the pressing force of the radiator 26 to the light emitting element 22 and the chip 23. , Radiator 26
Accordingly, the light emitting element 22 and the chip 23 can be stably held at a uniform height.

[0026]

According to the first aspect of the present invention, a light emitting element and a control circuit element are mounted on a wiring board via bumps.
Since the light-emitting element and the control circuit element are connected in advance, these elements can be attached to the wiring board because they are mounted on each other by down-down bonding , eliminating the need for complicated wiring on the wiring board. it can. Therefore, the number of steps for connecting both elements can be reduced, the yield of devices can be improved, and both elements can be easily mounted on the wiring board. As a result,
The workability and productivity of the device manufacturing operation can be improved, and the manufacturing cost can be reduced.

Further, since the two elements are not arranged separately on the wiring board, the size of the wiring board can be reduced.
Further, since one of the light emitting element and the control circuit element mounted on the wiring board is formed larger than the other, a plurality of the light emitting element and the control circuit element are arranged close to each other on the wiring board. And the other of the light emitting element and the control circuit element can be necessarily mounted thereon. Therefore, a large number of optical elements can be mounted on the wiring board to increase the light emitting dot density, and a highly accurate optical output device can be obtained. Also, the light emitting element
It is composed of an end face light emitting element having a light emitting part on the surface.
Light-emitting element and control circuit element, avoiding the light-emitting part
The light emitting element and the control circuit element can be laminated.
It will be easier.

According to the second aspect of the present invention, one of the light emitting element and the control circuit element is mounted on the element on one side with reference to the alignment mark provided on one of the light emitting element and the control circuit element. Therefore, one of the light emitting element and the control circuit element can be easily attached to the other with high accuracy. According to the invention described in claim 3,
A plurality of pressure members are provided on the back surface on the other side of any of the plurality of light-emitting elements and the control circuit element so as to be in contact with each block of the plurality of light-emitting elements and the control circuit element. Since the light emitting element and the control circuit element are held for each block between the blocks, the heating element and the control circuit element can be electrically stably joined, and the pressing force of the heating element and the control circuit element can be reduced for each block. And can be stably held on the wiring board.

Also, since the light emitting element and the control circuit element are radiated by the pressing member, heat generated in the heating element and the control circuit element is transferred from the back surfaces of both elements via the wiring board and the pressing member, respectively. It can be radiated, to improve the efficiency of heat dissipation Ru can be used a large light-emitting elements of the power.

According to the fourth aspect of the present invention, since one of the light emitting element and the control circuit element is directly mounted on the plane of the wiring board, the height of the light emitting element and the control circuit element varies. The two elements can be held at a uniform height by the pressing member. According to the fifth aspect of the present invention, since one of the light emitting element and the control circuit element is mounted on the wiring board via the intervening object, the height of the light emitting element and the control circuit element does not vary. The pressing force of the pressing member can be stably applied to the two elements, and the two elements can be stably held at a uniform height by the pressing member.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a mounting structure of a light output device according to the present invention.

FIG. 2 is a diagram illustrating a state in which a plurality of light emitting elements and the like are mounted on a wiring board according to one embodiment;

FIG. 3 is a structural view of an inclusion showing another embodiment of the mounting structure of the light output device according to the present invention.

FIG. 4 is a diagram showing a mounting structure of a conventional light output device.

FIG. 5 is a diagram showing a mounting structure of a conventional light output device.

[Explanation of symbols]

 21 Wiring board 22 Light emitting element 22a, 22b Electrode 22d Light emitting part 23 Drive LSI chip (control circuit element) 23a, 23b Electrode 26 Heat radiator (pressing member) 31 Adhesive (intervening substance) 32 Spacer (intervening substance)

Claims (5)

(57) [Claims] 1. A wiring board and a side surface mounted on the board.
An optical output device comprising: a plurality of light emitting elements including an end face light emitting element having a light emitting part in a unit; and a plurality of control circuit elements mounted on a wiring board and provided for each light emitting element so as to control the light emitting element. And mounting one of the light emitting element and the control circuit element on the substrate such that the opposite side to the electrode surface side faces the other, and emits the other of the light emitting element and the control circuit element on the electrode surface side. A bump is formed on one of the light emitting element and the control circuit element so as to face the electrode surface side of one of the element and the control circuit element.
Light output device, characterized in that mounted by face-down bonding to either the light emitting element and the control circuit element mounted on a wiring board formed larger than the other one of the light emitting element and the control circuit element via Mounting structure. 2. A light emitting device and a control circuit device, wherein the light emitting device and the control circuit device are mounted on one of the light emitting device and the control circuit device. Mounting method based on the alignment mark provided. 3. A plurality of pressure members which are in contact with each block of the plurality of light-emitting elements and the control circuit element are provided on a back surface on the other side of any one of the plurality of light-emitting elements and the control circuit element. By pressing one of the light emitting element and the control circuit element through the other of the light emitting element and the control circuit element, the light emitting element and the control circuit element are held for each block between the wiring board and the light emitting element and the control circuit element. 2. The light output device mounting structure according to claim 1, wherein heat is released from the light emitting element and the control circuit element by a pressing member. 4. The light-emitting element and the control circuit element.
The mounting structure for an optical output device according to claim 3 , wherein one of the mounting surfaces is directly mounted on a plane of the wiring board . 5. The light-emitting element and the control circuit element.
One must be mounted on the wiring board via an intervening object
Mounting structure of the light output device according to claim 3, wherein.