JP2021128950A - Manufacturing method of light-emitting device, and light-emitting device - Google Patents

Abstract

To realize a manufacturing method of a light emitting device having a plurality of light emitting units on a substrate at low cost.SOLUTION: A manufacturing method of a light emitting device includes the steps of: preparing a substrate in which a plurality of light emitting portions are arranged with their emission surfaces facing the front surface, and a plurality of electrodes respectively connected to the plurality of light emitting portions are exposed from the back surface; and forming wiring using a conductive paste on the back surface of the substrate, which is connected to at least some of the electrodes.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a light emitting device and a light emitting device.

A light emitting device in which a plurality of light emitting bodies are arranged on a resin and two adjacent light emitting bodies among the plurality of light emitting bodies are electrically connected by wiring has been proposed (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-0566650

In the light emitting device described in Patent Document 1, a wiring for electrically connecting two adjacent light emitting bodies is shown, but a specific method for forming the wiring is not shown.
There is a demand for cost reduction of the light emitting device, and accordingly, a method of manufacturing the wiring of the light emitting device at a lower cost is required.

According to the first aspect of the present invention, in the method of manufacturing a light emitting device, a plurality of light emitting portions are arranged with their emission surfaces facing the front surface, and a plurality of electrodes connected to the plurality of light emitting portions are back surfaces. It is provided that a substrate exposed from the above is prepared, and wiring using a conductive paste connected to at least a part of the electrodes is formed on the back surface of the substrate.
According to the second aspect of the present invention, in the light emitting device, a plurality of light emitting portions are arranged with their emission surfaces facing the front surface, and a plurality of electrodes connected to the plurality of light emitting portions are exposed from the back surface. The substrate is formed as described above, and the wiring formed by the conductive paste, which is connected to at least a part of the electrodes.

According to the manufacturing method of the present invention, a light emitting device including a plurality of light emitting units can be manufactured at low cost.

1 (a) to 1 (c) are views showing the light emitting device of the first embodiment. FIG. 1A is a perspective view of the light emitting device. FIG. 1B is a view of the light emitting device from the back side. FIG. 1 (c) is a cross-sectional view taken along the line segment A of FIG. 1 (b). 2 (a) to 2 (d) are cross-sectional views illustrating a first embodiment of a method for manufacturing a light emitting device. 3 (a) to 3 (c) are views for explaining a modified example 2 of a method for manufacturing a light emitting device. 4 (a) to 4 (c) are views for explaining a modified example 3 of a method for manufacturing a light emitting device. 5 (a) to 5 (d) are views for explaining a modified example 4 of a method for manufacturing a light emitting device. 6 (a) to 6 (d) are cross-sectional views illustrating a second embodiment of a method for manufacturing a light emitting device. 7 (a) to 7 (c) are cross-sectional views illustrating a second embodiment of a method for manufacturing a light emitting device following FIG. 8 (a) to 8 (d) are views for explaining a modified example 5 of a method for manufacturing a light emitting device. 9 (a) to 9 (b) are cross-sectional views illustrating a modified example 5 of a method for manufacturing a light emitting device following FIG. 10 (a) to 10 (c) are views for explaining a modified example 6 of a method for manufacturing a light emitting device. 11 (a) and 11 (b) are views for explaining modified examples 7 and 8 of a method for manufacturing a light emitting device.

(One Embodiment of a light emitting device)
Hereinafter, the light emitting device 1 of one embodiment will be described with reference to FIGS. 1 (a) to 1 (c). FIG. 1A is a perspective view of the light emitting device 1. As shown in FIG. 1A, the light emitting device 1 has a plurality of light emitting units 3 arranged in the substrate 2. As an example, the substrate 2 is a rectangular flat plate, and the directions parallel to each side of the rectangle are the X direction and the Y direction. Further, the X direction and the direction orthogonal to the Y direction are defined as the Z direction. In the X direction, the Y direction, and the Z direction indicated by the arrows in FIG. 1A and the subsequent drawings, the direction indicated by the arrow is the + direction. Further, in each of the following figures, the + X direction, the + Y direction, and the + Z direction indicate the same directions as the directions in FIG. 1A.

Hereinafter, the end surface of the substrate 2 in the + Z direction is referred to as a “front surface” 2f. Further, the end surface of the substrate 2 in the −Z direction is referred to as a back surface 2b (see FIG. 1B and the like).
The plurality of light emitting units 3 are arranged so that the injection surface 4, which is the surface on which light is emitted from the light emitting unit 3, is exposed from the front surface 2f of the substrate 2. The shape of the injection surface 4 is rectangular as an example, and the light emitting portions 3 are arranged two-dimensionally along the X direction and the Y direction as an example.

FIG. 1B is a plan view of the light emitting device 1 as viewed from the back surface 2b side. An electrode 5 electrically connected to each light emitting unit 3 is exposed on the back surface 2b of the light emitting device 1. Although the light emitting unit 3 is not visible from the back surface 2b side, the light emitting unit 3 is shown by a broken line in FIG. 1B for easy understanding.

Wiring 7a and 7b are formed on the back surface 2b, which are electrically connected to the electrode 5 and for supplying electric power to the light emitting unit 3 via the electrode 5. Here, the wiring 7a is a wiring for supplying electric power to the light emitting unit 3 from a power source provided outside the light emitting device 1, and the wiring 7b locally connects two or three or more light emitting units 3. It is a wiring for connecting to. In the present specification, the wiring 7a and the wiring 7b are collectively referred to as wiring 7, or each of them is also referred to as wiring 7.

FIG. 1 (c) is a partial cross-sectional view (XZ cross-sectional view) of the light emitting device 1 in the line segment A shown in FIG. 1 (b). The cross section is shown.
As an example, the substrate 2 is mainly composed of a resin such as a silicon resin or an epoxy resin, and a plurality of light emitting units 3 are included inside the substrate 2.

As an example, the light emitting unit 3 includes a light emitting element 10 including a light emitting diode (LED), a transparent substrate 11 such as sapphire laminated on the light emitting element 10, a fluorescent layer 12 containing a fluorescent substance, and a protective layer 13. .. In the light source device 1 of one embodiment, the surface of the protective layer 13 on the + Z side is the emission surface 4 of the light emitting unit 3.

The electrode 5 is made of a conductive substance such as copper, and its end surface on the −Z side is flush with the back surface 2b of the substrate 2.
As described above, the wiring 7 electrically connected to the electrode 5 is formed on the back surface 2b. Although not shown in FIG. 1B, an insulating protective film 8 is formed on the back surface 2b so as to cover at least a part of the wiring 7. The protective film 8 secures the insulating property of the wiring 7 and prevents a short circuit due to migration of the wiring 7. However, if the migration resistance of the wiring 7 is sufficient, the protective film 8 may be omitted.

Although only one layer of the wiring 7 is shown in FIGS. 1B and 1C, the wiring 7 is formed over two or more layers as described in the manufacturing method described later. You may. In that case, a protective film 8 as an insulating layer is arranged at least a part of each layer of each of the multilayer wirings 7.

In the light emitting device 1 of one embodiment, the wiring 7 is a wiring formed by using the conductive paste. The conductive paste is obtained by dispersing a powder (filler) made of a conductor such as metal or carbon black in a polymer binder. As the conductive paste used to form the wiring 7, for example, a silver paste containing a silver filler, a copper paste containing a copper filler, a gold paste containing a gold filler, or an aluminum paste containing an aluminum filler can be used. ..

In the light emitting device 1 of one embodiment, as an example, the wiring 7 may be formed by forming a conductive paste at a predetermined position on the substrate 2 and sintering the filler which is a conductor by heating. Various modifications of the light emitting device 1 are configured by various methods for forming the wiring 7 described later.

On the other hand, conventionally, fine wiring has been formed by a lithography method. That is, after forming a film of a conductor such as metal on the entire surface of the substrate on which the wiring should be formed, the unnecessary portion is removed from the film of the conductor and the necessary portion remains to form the wiring. Therefore, in the past, a much larger amount of conductor was required than was ultimately used as wiring. Further, since the resin constituting the substrate 2 is easily affected by the chemical treatment, a treatment for protecting the resin is required in the etching treatment in the lithography method, the number of steps is further increased, and the cost is increased.

In the light emitting device 1 of one embodiment, since the wiring 7 is formed of the conductive paste, the amount of conductors such as metal required to form the wiring 7 and the number of steps required are compared with those of the conventional ones. Can be reduced. Therefore, the production cost in forming the wiring 7 can be reduced.

Further, since the wiring 7 is formed of the conductive paste, the thickness of the wiring 7 (size in the Z direction) can be reduced. Thereby, the overall thickness of the light source device 1 can be reduced.
On the other hand, the thickness of the entire wiring layer formed by conventional lithography in the Z direction is about 50 to 60 μm if the wiring layer has a two-layer structure, and conventionally, the light source device cannot be made sufficiently thin. was difficult.

In the light emitting device 1 of one embodiment, since the wiring 7 is formed of the conductive paste, the thickness of each layer of the wiring 7 can be reduced to 10 μm or less. Even if the thickness of the protective film 8 is included, it is 20 μm or less, and if the wiring layer has a two-layer structure, it is 30 μm or less. Therefore, even if the wiring 7 is formed over four layers, the total thickness of the four layers of the wiring 7 and the protective film 8 can be 100 μm or less, and the light source device can be made sufficiently thin. can.

(Effect of the light emitting device of one embodiment)
(1) In the light emitting device of one embodiment, the emission surfaces 4 of the plurality of light emitting units 3 are arranged so as to be exposed from the front surface 2f, and the plurality of electrodes 5 connected to the plurality of light emitting units 3 are arranged on the back surface 2b. It includes a substrate 2 exposed from the surface and a wiring 7 formed of a conductive paste, which is connected to at least a part of the electrodes 5.
With this configuration, the amount of conductors such as metal required to form the wiring 7 can be reduced as compared with the conventional case, and a low-cost light source device 1 can be realized.

(First Embodiment of Manufacturing Method of Light Emitting Device)
Hereinafter, the manufacturing method of the first embodiment will be described with reference to FIGS. 2 (a) to 2 (c).

(Step 1)
A substrate 2 in which the injection surfaces 4 of the plurality of light emitting units 3 are arranged so as to be exposed from the front surface 2f, and the plurality of electrodes 5 connected to the plurality of light emitting units 3 are exposed from the back surface 2b. Prepare. That is, the substrate 2 to be prepared is a substrate on which the wiring 7 and the protective film 8 are not formed with respect to the light emitting device 1 of the embodiment shown in FIGS. 1 (a) to 1 (c).

FIG. 2A is a diagram showing an XZ cross section of the substrate 2 to be prepared in the line segment A of FIG. 1B. Note that FIG. 2A shows the vertical direction (Z direction) inverted from that of FIG. 1C described above.
Unlike the light emitting device 1 of the embodiment shown in FIG. 1 (c), the wiring 7 and the protective film 8 are not yet formed on the substrate 2 shown in FIG. 2 (a).
In the substrate 2, for example, a plurality of light emitting portions 3 on which the electrodes 5 are formed are arranged in the same plane (in the XY plane) with the injection surface 4 facing the + Z direction, and they are collectively molded with resin. Can be formed by

(Step 2)
As shown in FIG. 2B, the conductive pastes 6a and 6b are formed on the back surface 2b of the substrate 2 at positions where the wiring 7 should be formed. The conductive paste 6a is a portion that becomes the wiring 7a due to sintering described later, and the conductive paste 6b is a portion that becomes the wiring 7b. The conductive paste 6a and the conductive paste 6b are combined, or each of them is also referred to as a conductive paste 6.
As the conductive paste, as described above, a gold paste, a silver paste, a copper paste, or the like can be used.

As an example, the conductive paste 6 is formed on the back surface 2b of the substrate 2 by printing the conductive paste 6 over the entire surface of the back surface 2b by screen printing. By printing over the entire surface of the back surface 2b at once, the conductive paste 6 can be formed at a high processing speed.

The conductive paste 6 needs to be formed in a position-aligned manner with at least a part of a plurality of electrodes 5 formed on the back surface 2b of the substrate 2. Therefore, prior to the formation of the conductive paste 6 by screen printing or the like, the positions of the plurality of electrodes 5 in the X direction and the Y direction are detected by, for example, an optical position detecting device by using a technique such as pattern matching. Then, based on the detected position information, the conductive paste 6 is formed according to the position of the electrode 5. As for the optical position detection device and the method such as pattern matching, a known technique may be used, and the description thereof will be omitted.

(Step 3)
The conductive paste 6 formed on the back surface 2b of the substrate 2 is sintered to form the wiring 7. FIG. 2C shows a state in which the wiring 7 is formed on the back surface 2b by sintering the conductive paste 6. Sintering is performed by heating the substrate 2 and the conductive paste 6 to about 200 ° C. to 300 ° C. When a silver paste is used as the conductive paste, the sintering temperature may be 200 ° C. or lower.

(Step 4)
A protective film 8 covering at least a part of the wiring 7 is formed on the back surface 2b of the substrate 2 on which the wiring 7 is formed. FIG. 2D shows the substrate 2 on which the protective film 8 is formed. The protective film 8 is formed, for example, by pasting or printing an insulating resin.
By the above steps, the light emitting device 1 of one embodiment is completed.

(Effect of the first embodiment of the method for manufacturing a light emitting device)
(2) In the manufacturing method of the first embodiment, a plurality of light emitting units 3 are arranged with their injection surfaces 4 facing the front surface 2f, and a plurality of electrodes 5 connected to the plurality of light emitting units 3 are arranged on the back surface 2b. A substrate 2 formed so as to be exposed from the substrate 2 is prepared, and a wiring 7 using a conductive paste 6 connected to at least a part of the electrodes 5 is formed on the back surface 2b of the substrate 2. ing.
With this configuration, the amount of conductive material such as metal required for forming the wiring 7 can be reduced, the wiring 7 can be formed at low cost, and the light emitting device 1 can be manufactured at low cost. ..
(3) Further, the conductive paste 6 is formed on the back surface 2b of the substrate 2, the formed conductive paste 6 is sintered, and the wiring 7 is formed on the back surface 2b of the substrate 2, thereby simplifying the manufacturing process. At the same time, the light emitting device 1 can be manufactured at low cost.

(Modification 1 of the manufacturing method of the light emitting device)
Hereinafter, the first modification will be described. Most of the first modification is common to the first embodiment described above. Therefore, the configurations different from those of the first embodiment will be described below, and the common configurations will be omitted as appropriate.

In the first embodiment, in step 2, a method of forming the conductive paste 6 over the entire surface of the back surface 2b at a time, such as screen printing, was used.
On the other hand, in the first modification of the manufacturing method, the conductive paste 6 is formed on the back surface 2b of the substrate 2 by using a dispenser that discharges the conductive paste 6 toward the substrate 2. In this case, the conductive paste 6 may be discharged while scanning one dispenser two-dimensionally relative to the substrate 2. Alternatively, the conductive paste 6 may be discharged while scanning a plurality of dispensers two-dimensionally relative to the substrate 2. Further, the conductive paste 6 may be ejected while scanning the so-called inkjet printer head including a large number of dispensers one-dimensionally or two-dimensionally with respect to the substrate 2.

When forming the conductive paste 6 using a dispenser or an inkjet printer head, the position of the conductive paste 6 on the substrate 2, that is, the position of the wiring 7 can be freely changed by changing the ejection timing in the relative scanning and the like. Can be changed. In other words, the plurality of conductive pastes 6 on the substrate 2, that is, the plurality of wirings 7 are formed by changing the positional relationship between them with respect to the design positional relationship. The change to the design value of the positional relationship between the two may be such that each position of the plurality of conductive pastes 6 expands and contracts uniformly as a whole (scaling), and each position of the plurality of conductive pastes 6 is randomly assigned. It may be changed to.
Therefore, even if the substrate 2 is deformed as a whole or locally due to heat shrinkage or the like and the electrode 5 deviates from the design position, it is adjusted to the detected position of the electrode 5. By correcting the discharge position of the conductive paste 6, the wiring 7 can be formed by accurately aligning the position with the electrode 5.

The change in the positional relationship between the conductive pastes 6 corresponding to the wiring 7 may be such that the positions (arrangement intervals) of the plurality of conductive pastes 6 on the substrate 2 are uniformly expanded and contracted as a whole. , A plurality of conductive pastes 6 may be individually and locally displaced.

For the locally deformed substrate 2, the conductive paste 6 is formed by locally displacing each of the plurality of conductive pastes 6, so that the conductive paste 6 can be accurately attached to each of the electrodes 5 on the substrate 2. It can be formed by aligning the positions.
In this case, the positions of a large number of electrodes 5, for example, about 20% or more of all the electrodes 5, are detected, information on the displacement of the electrodes 5 is calculated based on the detection result, and each of them is calculated based on the calculated information. The conductive paste 6 may be locally displaced and formed so as to be aligned with each electrode 5.

On the other hand, when the conductive paste 6 is collectively formed by screen printing or the like as in the first embodiment described above, each position of the conductive paste 6 to be formed is fixed by the screen mask used. The positional relationship cannot be changed. Therefore, when the conductive paste 6 is collectively formed by screen printing or the like, if the substrate 2 is irregularly deformed, the wiring 7 is connected to all the electrodes 5 arranged on the substrate 2. It becomes difficult to form by accurately aligning the positions.

(Effect of Modification 1 of the method for manufacturing a light emitting device)
(4) In the first embodiment described above, the first modification further detects the position information of the electrodes 5 formed on the first substrate 2, and based on the position information, at least a part of the wiring 7 is connected to each other. It is formed by changing the positional relationship of.
With this configuration, the wiring 7 can be formed by accurately aligning the wiring 7 with the electrode 5 at each portion on the substrate 2.

(Modification 2 of the manufacturing method of the light emitting device)
Hereinafter, the second modification will be described. Most of the modified example 2 is common to the above-mentioned modified example 1. Therefore, a configuration different from that of the first modification will be described below, and a common configuration will be omitted as appropriate.

In the second modification, the conductive paste 6 is formed by using a dispenser or an inkjet printer head for the portion of the wiring 7 that requires high position accuracy. On the other hand, the conductive paste 6 is collectively formed by screen printing or the like for the portion of the wiring 7 whose required position accuracy is not so high.

3 (a) to 3 (c) are views showing a process of forming the conductive paste 6 in the second modification of the manufacturing method of the light emitting device, and are views of the substrate 2 viewed from the back surface 2b side.
In the second modification of the manufacturing method, in the step corresponding to the step 2 in the first embodiment described above, the film is formed on the back surface 2b of the substrate 2 as shown in FIG. 3A, similarly to the first embodiment. The positions of the electrode 5 in the X direction and the Y direction are detected.

Based on the detection result of the position of the electrode 5, as shown in FIG. 3B, a dispenser or an inkjet printer head is used in a part where high position accuracy is required, such as a part connected to the electrode 5. The conductive pastes 6b and 6c are formed by aligning the positions with the electrodes 5.
Subsequently, the conductive paste 6d is collectively formed on the portion where the required position accuracy is not so high by screen printing or the like. A part of the conductive paste 6d overlaps with the previously formed conductive paste 6c, and the conductive paste 6c and the conductive paste 6d are integrated to form the conductive paste 6a.

After forming the conductive paste 6d, the conductive pastes 6 (6a to 6d) are sintered to form a wiring 7 similar to that shown in FIG. 1 (b).
The conductive paste 6d formed by batch formation may be formed first, and the conductive pastes 6b and 6c formed by the dispenser or the inkjet printer head may be formed later.
Further, after sintering the conductive pastes 6b and 6c or the conductive paste 6d formed earlier, the conductive pastes 6d or the conductive pastes 6b and 6c may be formed later and sintered.

(Effect of Modification 2 of the Manufacturing Method of Light Emitting Device)
(5) In the modified example 2, the positional relationship between a part of the wiring 7 (the portion corresponding to the conductive pastes 6b and 6c) is further changed based on the position information of the electrode 5 in the above-described modified example 1. And the wiring 7 (the part corresponding to the conductive paste 6d) other than a part is formed by fixing the positional relationship between them.
With this configuration, it is possible to realize a manufacturing method having both high processing capacity and high position matching accuracy.

(Modification 3 of the manufacturing method of the light emitting device)
Hereinafter, the third modification will be described. Most of the modified examples 3 are common to the above-described first embodiment. Therefore, the configurations different from those of the first embodiment will be described below, and the common configurations will be omitted as appropriate.

4 (a) to 4 (c) are views showing the process of forming the conductive paste 6 in the modified example 3, and show a cross-sectional view of the substrate 2.
In the third modification, in the step corresponding to the step 2 in the first embodiment, as shown in FIG. 4A, the resist 9 is first formed on the back surface 2b of the substrate 2. The resist 9 may be a dry film resist attached by laminating or the like, or may be applied by spin coating or spray coating.

Subsequently, the position of the electrode 5 on the back surface 2b is detected through the resist 9, and a part of the resist 9 is exposed based on the detected position information of the electrode 5, and a part of the resist 9 is removed.
FIG. 4B is a diagram showing the resist 9 from which the resist 9 has been partially removed, and the groove portion 9o is a portion from which the resist 9 has been removed. The groove portion 9o may be a portion where the resist 9 is removed by development after exposure, or may be a portion where the resist 9 is sublimated and removed by exposure.

As shown in FIG. 4C, the groove portion 9o, which is the portion from which the resist 9 has been removed, is filled with the conductive paste 6. In this case, the conductive paste 6 can be filled in the groove portion 9o by applying the conductive paste 6 to the entire surface of the back surface 2b of the substrate 2 covered with the resist 9. The conductive paste 6 applied to the back surface 2b and not filled in the groove 9o is recovered and reused for filling the groove 9o of the other substrate 2.

Subsequently, in the same manner as in step 3 of the first embodiment described above, the substrate 2 is heated to sinter the conductive paste 6 to form the wiring 7 (not shown in FIG. 4C). After that, by removing the resist 9, the wiring 7 is formed on the back surface 2b in the same manner as in FIG. 2 (c) described above.

In the exposure to the resist 9 for forming the groove portion 9o, at least a part of the groove portion 9o is mutually exposed according to the displacement of the position of the electrode 5 due to the deformation of the substrate 2, as in the above-described modification 1. The exposure may be performed by changing the positional relationship between them. For this purpose, the resist 9 may be exposed using a laser beam scan type exposure apparatus or an exposure apparatus using a variable shaping mask such as a multi-mirror device. As a result, even when the substrate 2 is deformed, the wiring 7 can be accurately formed by accurately aligning the groove portion 9o with the electrode 5 at each portion on the substrate 2.

Further, as in the above-described modification 2, a laser beam scan type exposure device is used for the groove portion 9o corresponding to the wiring 7 that requires high position accuracy, and the groove portion 9o corresponding to the wiring 7 that does not require high position accuracy is used. May be exposed using an exposure apparatus that uses a fixed mask.
Before removing the resist 9, the conductive paste 6 that may remain on the resist 9 may be removed by polishing.
When a so-called permanent resist such as an ABF film is used as the resist 9, it is not necessary to remove the resist 9.

(Effect of Modification 3 of Method for Manufacturing Light Emitting Device)
(6) In the first embodiment described above, in the modified example 3, the conductive paste 6 is further formed on the back surface 2b of the substrate 2, the resist 9 is formed on the back surface 2b of the substrate 2, and a part of the resist 9 is formed. The groove portion 9o is formed by removing the resist 9, and the groove portion 9o from which the resist 9 has been removed is filled with the conductive paste 6.
With this configuration, the conductive paste 6 and the wiring 7 are formed on the substrate 2 with high processing capacity without directly ejecting the conductive paste 6 onto the back surface 2b of the substrate 2 by using the light exposure technology capable of high-speed processing. can do.

(Modification example 4 of the manufacturing method of the light emitting device)
Hereinafter, the modified example 4 will be described with reference to FIGS. 5 (a) to 5 (d). Most of the modified examples 4 are common to the above-described first embodiment. Therefore, the configurations different from those of the first embodiment will be described below, and the common configurations will be omitted as appropriate.

5 (a) to 5 (d) are views showing a process of forming the wiring 7 in the modified example 4, and show a cross-sectional view of the substrate 2.
The modified example 4 is different from the above-described first embodiment in that the wiring 7 is a so-called multi-layer wiring.

Unlike the protective film 8 of FIG. 2D, the protective film 8a of FIG. 5A has an opening 15o formed at a position corresponding to a part of the wiring 7a. The substrate 2 shown in FIG. 5 (a) can be formed by partially printing the protective film 8a, which is an insulating resin, on the substrate 2 shown in FIG. 2 (c).

As shown in FIG. 5 (b), the wiring 7e is formed on the protective film 8a of the substrate 2 shown in FIG. 5 (a). A part of the wiring 7e is filled in the opening 15o and formed so as to be electrically connected to the wiring 7a. The wiring 7e can be formed by forming a conductive paste 6 (not shown in FIG. 5B) using the various forming methods described above and sintering the conductive paste 6 (not shown in FIG. 5B).

Subsequently, as shown in FIG. 5C, the protective film 8b, which is an insulating resin, is partially printed on the wiring 7e and the protective film 8a. In this printing, an opening 16o is formed at a corresponding position of the wiring 7e.
After that, as shown in FIG. 5D, the wiring 7f is formed in the opening 16o. The wiring 7f can also be formed by forming a conductive paste 6 (not shown in FIG. 5D) using the various forming methods described above and sintering the conductive paste 6.

The opening 15o may be formed at a corresponding position of the wiring 7b instead of the wiring 7a, or may be formed at a corresponding position of the wiring 7a and the wiring 7b.
As the protective film 8a formed between the two layers of wirings 7a and 7b and the wiring 7e, an epoxy resin having low hygroscopicity may be used in order to prevent deformation due to moisture absorption.
Note that FIGS. 5A to 5D show a two-layer wiring composed of wirings 7a and 7b and wiring 7e, but the wiring and the protective film are further laminated on the protective film 8b. By forming the wiring, it is possible to form the wiring laminated in three or more layers.

(Effect of Modification 4 of Method for Manufacturing Light Emitting Device)
(7) In the fourth modification, in the first embodiment of the above-mentioned light emitting device, the wiring 7 (7a to 7f) is further formed in a multi-layered manner via an insulating layer (protective film 8a) at least in a part.
With this configuration, it is possible to manufacture a multilayer wiring having a high degree of freedom of wiring to the light emitting unit 3 at low cost.

(Second Embodiment of Manufacturing Method of Light Emitting Device)
Hereinafter, the second embodiment will be described with reference to FIGS. 6 and 7. Most of the second embodiment is common to the first embodiment described above. Therefore, the configurations different from those of the first embodiment will be described below, and the common configurations will be omitted as appropriate.

In the first embodiment, the conductive paste 6 is directly formed on the back surface 2b of the substrate 2, and the formed conductive paste 6 is sintered to form the wiring 7.
On the other hand, in the second embodiment, after the wiring 7 and the protective film 8 are formed on the temporary substrate, the wiring 7 and the protective film 8 formed on the temporary substrate are attached to the back surface 2b of the substrate 2. , The wiring 7 of the substrate 2 is formed.

Also in the second embodiment, the preparation of the substrate 2 in the above-mentioned step 1 is the same as that in the first embodiment, and thus the description thereof will be omitted.
In the second embodiment, the following steps 2A to 8A are executed instead of the steps 2 to 4 in the first embodiment.

(Step 2A)
FIG. 6A is a diagram showing an XZ cross section of a part of the temporary substrate 20 that is bonded to the portion of the line segment A of FIG. 1B in the substrate 2 when it is bonded to the substrate 2 in the step 8A.
As an example, a temporary substrate 20 made of stainless steel is prepared. Like the substrate 2, the temporary substrate 20 is a substrate having a plane extending along the XY plane, and its size in the X direction and the Y direction is substantially the same as that of the substrate 2.

(Step 3A)
As shown in FIG. 6A, the conductive paste 6h is formed on the temporary substrate 20 by using the various forming methods described above. Then, the temporary substrate 20 is heated to sinter the conductive paste 6h to form the wiring 7h. Similarly, the subsequent wirings 7a, 7b, 7g, and 7f are formed by forming a conductive paste on the temporary substrate 20 and sintering the conductive paste.

(Step 4A)
As shown in FIG. 6B, the protective film 8c is formed on the temporary substrate 20. The thickness of the protective film 8c is such that the upper end (end in the + Z direction) of the wiring 7h is exposed from the protective film 8c. The protective film 8c may also be formed by printing a resin in the same manner as the protective film 8a described above.

(Step 5A)
As shown in FIG. 6C, wiring 7g and wiring 7f are formed on the protective film 8c and the wiring 7h using a conductive paste (not shown).

(Step 6A)
As shown in FIG. 6D, the protective film 8b is formed on the wiring 7g and the protective film 8c. The thickness of the protective film 8b is such that the upper end (end in the + Z direction) of the wiring 7f is exposed from the protective film 8b. Further, as shown in FIG. 6D, the wiring 7a and the wiring 7b are formed on the protective film 8b and the wiring 7f using a conductive paste (not shown).

(Step 7A)
As shown in FIG. 7A, the protective film 8a is formed on the protective film 8b. The thickness of the protective film 8a is such that the upper ends (ends in the + Z direction) of the wirings 7a and 7b are exposed from the protective film 8a.

(Step 8A)
As shown in FIG. 7B, the temporary substrate 20 for which the steps 7A have been completed is attached to the back surface 2b of the substrate 2. When attaching to the substrate 2, the wirings 7a and 7b of the temporary substrate 20 and the corresponding electrodes 5 on the substrate 2 are aligned and attached using a conductive film or a conductive adhesive paste. match.

(Step 9A)
The temporary substrate 20 is peeled off from the substrate 2 to which the temporary substrate 20 shown in FIG. 7B is attached, leaving the wirings 7a to 7f and the protective films 8a to 8c on the substrate 2. FIG. 7 (c) shows the substrate 2 in a state where the temporary substrate 20 is peeled off.

By the above steps 1 and steps 2A to 9A, the light emitting device 1 of the embodiment shown in FIG. 1 can be manufactured.
In the second embodiment, the wirings 7a to 7h of the two-layer wiring are formed, but by omitting the formation of the wirings 7g and 7h and the protective film 8c, the same as in the first embodiment of the above manufacturing method. , The light emitting device 1 having one layer of wiring may be manufactured.
Alternatively, the light emitting device 1 having three or more layers of wiring may be manufactured by further laminating and forming the wiring and the protective film on the temporary substrate 20.

In the second embodiment, since the conductive paste 6h and the like are not sintered on the substrate 2, it is not necessary to heat the substrate 2 to about 200 ° C. Therefore, it is possible to prevent adverse effects such as thermal deformation on the substrate 2 in the manufacturing process.

The temporary substrate 20 is peeled off, for example, by mechanically peeling the temporary substrate 20 from the wiring 7h and the protective film 8f. For this purpose, the temporary substrate 20 uses a substrate made of a material having a weak bonding force with the sintered body of the conductor paste constituting the wiring 7h and the resin constituting the protective film 8c and having strong mechanical strength. Is preferable. As the temporary substrate 20 satisfying this condition, for example, a stainless steel substrate such as SUS304 (ISO 4301-304-00-I) or SUS430 (ISO 4016-430-00-I) can be used.

The stainless steel temporary substrate 20 may be peeled off from the substrate 2 and washed, and then used again as the temporary substrate 20 in the manufacture of the light emitting device 1.
A copper substrate or a glass substrate may be used as the temporary substrate 20.

(Modification 5 of the manufacturing method of the light emitting device)
Hereinafter, the manufacturing method of the modified example 5 will be described with reference to FIGS. 8 and 9. In the modified example 5, a glass temporary substrate 21 is used instead of the stainless steel temporary substrate 20 in the second embodiment described above. Further, as the substrate 2 and the temporary substrate 21, those whose X-direction and Y-direction sizes are larger than the X-direction and Y-direction sizes of the final product, the light emitting device 1, are used. However, the other manufacturing processes are generally the same as those in the second embodiment described above. Therefore, the configurations different from those of the second embodiment will be described below, and the common configurations will be omitted as appropriate.

(Step 2B)
FIG. 8A is a diagram showing an XZ cross section of a part of the temporary substrate 21 that is bonded to the portion of the line segment A of FIG. 1B on the substrate 2 when it is bonded to the substrate 2 in step 6B. However, as described above, since the sizes of the substrate 2 and the temporary substrate 21 in the X and Y directions are larger than the size of the final product, the light emitting device 1, in FIG. 8 (a), FIG. 1 (b) is shown. It represents the XZ cross section of the portion extending in the −X direction from the portion of the line segment A.

As shown in FIG. 8A, a glass temporary substrate 21 on which the first temporary layer 22 and the second temporary layer 23 are formed in this order from the temporary substrate 21 side is prepared on the + Z side surface. .. Here, the second temporary layer 23 is mainly composed of a metal such as copper, which has high conductivity and is relatively easy to chemically etch, and the first temporary layer 22 has adhesion to glass such as nickel and titanium. It is mainly composed of high-grade metal. The thickness of the temporary substrate 21 is, for example, about 1 to 1.5 mm. The thickness of the second temporary layer 23 is, for example, about 1 μm or less.

(Step 3B)
As shown in FIG. 8B, a conductive paste is formed on the second temporary layer 23 on the temporary substrate 21 by using the various forming methods described above, and the temporary substrate 21 is heated to be conductive. The paste is sintered to form 7 g of wiring.
When the second temporary layer 23 contains copper as a main component, a copper paste may be used as the conductive paste. Thereby, the adhesion of the wiring 7g to the second temporary layer 23 can be improved.

(Step 4B)
After that, as shown in FIG. 8C, a conductive paste is formed on a part of the wiring 7g, and this is sintered to form the wiring 7f. Further, a protective film 8b is formed on the wiring 7g and on the temporary substrate 21. The thickness of the protective film 8b is such that the upper end (end in the + Z direction) of the wiring 7f is exposed from the protective film 8b. The protective film 8b may also be formed by printing a resin.

(Step 5B)
As shown in FIG. 8D, the wiring 7a and the wiring 7b are formed on the protective film 8b and the wiring 7f using the conductive paste.
A metal such as copper may be selectively formed on the formed wirings 7a and 7b by electroplating to increase the thickness of the wirings 7a and 7b and reduce the electric resistance.
After that, the protective film 8a is formed on the protective film 8b. The thickness of the protective film 8a is such that the upper ends (ends in the + Z direction) of the wirings 7a and 7b are exposed from the protective film 8a.

(Step 6B)
As shown in FIG. 9A, the temporary substrate 21 for which the steps up to 5B have been completed is attached to the back surface 2b of the substrate 2. When attaching to the substrate 2, the wirings 7a and 7b of the temporary substrate 21 and the corresponding electrodes 5 on the substrate 2 are aligned and attached using a conductive film or a conductive adhesive paste. match.

(Step 7B)
Both ends in the X direction and both ends in the Y direction of the peripheral portions of the bonded temporary substrate 21 and the substrate 2 shown in FIG. 9A are cut by the cut surface DC shown by the broken line. Note that FIG. 9A shows only the cut surface DC in the vicinity of the temporary substrate 21 and the end portion of the substrate 2 in the −X direction.
The cutting surface DC is cut by, for example, a dicing saw or a cutting by an impact such as mechanically hitting the peripheral portion of the substrate 2.
By cutting on the cut surface DC, the first temporary layer 22 and the second temporary layer 23 formed on the surface of the temporary substrate 21 are exposed on the cut surface DC.

(Step 8B)
With the first temporary layer 22 and the second temporary layer 23 as boundaries, the temporary substrate 21 is peeled off from the substrate 2 to which the temporary substrate 21 is attached, leaving the wirings 7, 7f, 7g and the protective films 8a, 8b on the substrate 2. do. Since the first temporary layer 22 and the second temporary layer 23 are exposed to the cut surface DC by the above-mentioned cutting, the temporary substrate 21 is efficiently peeled off by using the first temporary layer 22 and the second temporary layer 23 as a peeling layer. can do.

(Step 9B)
After that, the first temporary layer 22 and the second temporary layer 23 remaining on the back surface 2b side of the substrate 2 are removed by an etching process or the like.
FIG. 9B shows a substrate 2 in a state in which the temporary substrate 21 is peeled off and the first temporary layer 22 and the second temporary layer 23 are removed.
By the above steps 1 and steps 2B to 9B, the light emitting device 1 of the embodiment shown in FIG. 1 can be manufactured.
In the modified example 5, the method of attaching the substrate 2 after the step 5B was used, but the light emitting portion 3 may be individually mounted instead of the substrate 2 including the plurality of light emitting portions 3.

(Variation example 6 of the manufacturing method of the light emitting device)
Hereinafter, the manufacturing method of the modified example 6 will be described with reference to FIG. Since the manufacturing process of the modified example 6 is generally the same as that of the above-mentioned modified example 5, the configuration different from the modified example 5 will be described below, and the common configuration will be omitted as appropriate.

In the modified example 6, after the completion of the step 3B of the modified example 5, as shown in FIG. 10 (a), the wiring 7 g and the second temporary layer 23 (+ Z side) are highly conductive and chemically. A conductive layer 24 containing a metal such as copper, which is relatively easy to perform, is formed by plating or the like. The conductive layer 24 is made of a material having a higher etching rate than the wiring 7 g. Conversely, in the modification 6, the wiring 7g is made of a material having a lower etching rate than the conductive layer 24. As an example, the wiring 7 g may be formed of sintered silver paste, and the conductive layer 24 may be formed by copper plating.

In the modified example 6, the above-mentioned steps 4B to 8B are then performed in the same manner as in the modified example 5. FIG. 10B shows the state of the substrate 2 in which the temporary substrate 21 in step 8B has been peeled off in the modified example 6. A part of the second temporary layer 23 remains on the lower side (−Z side) of the wiring 7g formed on the substrate 2 and the lower side of a part of the conductive layer 24.

After that, in the modified example 6, the process of the above-mentioned step 9B is performed in the same manner as in the modified example 5. The remaining second temporary layer 23 is removed by the etching process in step 9B. Further, a part of the conductive layer 24 made of a material having a higher etching rate than the wiring 7g is removed by using the wiring 7g as an etching mask. That is, in the conductive layer 24, a portion formed between the plurality of wirings 7g and conducting the plurality of wirings 7g with each other is removed by this etching process.

FIG. 10C shows the state of the substrate 2 in which the process of step 9B has been completed in the modified example 6. By the etching process in step 9B, the conductive layer 24 covers the periphery of the wiring 7g except for the exposed surface of the wiring 7g. As a result, even if the wiring 7g formed by the conductive paste is thin, by patterning the conductive layer 24 using the wiring 7g as an etching mask, the wiring 7g and the conductive layer 24 as a whole are thick as a whole, that is, the electric resistance is small. Wiring can be formed.

From another point of view, the wiring 7g formed by the conductive paste can be thinned, whereby the thinner or narrower pitch wiring 7g can be formed using the less viscous conductive paste. It will be possible.
The film formation of the conductive layer 24 and the etching using the wiring 7g as an etching mask in the modification 6 may also be used in the manufacturing method of the second embodiment using the stainless steel temporary substrate 20 described above. ..

Also in the second embodiment, the modified example 5, and the modified example 6 described above, the formation of the wiring 7a, 7b, 7f, 7g, 7h (hereinafter, also collectively referred to as the wiring 7A) on the temporary substrate 20 is conductive. The sex paste 6h or the like may be collectively formed on the temporary substrate 20 by screen printing or the like, or may be individually formed by a dispenser or the like.
When the conductive paste 6h or the like is individually formed by a dispenser or the like, the position of the electrode 5 formed on the substrate 2 to be bonded is measured, and the conductive paste 6h or the like and the wiring 7A are measured based on the measured position information. The relative positional relationship of may be corrected. As a result, even when the substrate 2 is deformed, the wiring 7A can be formed with high accuracy in position alignment with respect to the electrode 5.

Also in the second embodiment, the modified example 5 and the modified example 6 described above, the resist 9 is formed on the temporary substrate 20, the resist 9 is exposed to form the groove portion 9o, and the conductive paste 6h or the like is applied to the groove portion 9o. It may be filled to form the wiring 7A. In this case, a laser beam scan type exposure device is used for the groove 9o corresponding to the portion of the wiring 7A that requires high position accuracy, and a fixed mask is used for the groove 9o corresponding to the portion that does not require high position accuracy. The exposure may be performed using an exposure apparatus to be used.

(Effects of the second embodiment of the method for manufacturing a light emitting device, modifications 5 and 6)
(8) In the second embodiment, the modified example 5 and the modified example 6, a plurality of light emitting units 3 are arranged with their emission surfaces 4 facing the front surface 2f, and a plurality of light emitting units 3 are connected to the plurality of light emitting units 3. A substrate 2 in which the electrode 5 is formed so as to be exposed from the back surface 2b is prepared, and a wiring 7 using the conductive paste 6 connected to at least a part of the electrode 5 is formed on the back surface 2b of the substrate 2. It has to do.
Further, the conductive paste 6h and the like are formed on the temporary substrates 20 and 21, the formed conductive paste 6h and the like are sintered to form wiring, and the wiring 7 formed on the temporary substrates 20 and 21 is attached to the substrate 2. The temporary substrate 20 is attached to the back surface 2b of the substrate 2 and peeled from the wiring 7 attached to the back surface 2b of the substrate 2 to form the wiring 7 on the back surface 2b of the substrate 2.
With this configuration, in addition to the effects obtained in the first embodiment described above, it is possible to prevent thermal deformation of the substrate 2 in the manufacturing process, and it is possible to realize a higher-definition light source device 1.

(9) In the modified example 6, the conductive layer 24 is further formed on the temporary substrate 21 including the wiring 7g with a conductive material having an etching rate lower than that of the wiring 7g, and after the temporary substrate 21 is peeled from the wiring 7g, the wiring 7g Is used as a mask to etch the conductive layer 24. With this configuration, even if the wiring 7g formed by the conductive paste is thin, it is possible to form a wiring having a small electric resistance as a whole between the wiring 7g and the conductive layer 24. Further, the wiring 7g formed by the conductive paste can be made thinner, which makes it possible to form the wiring 7g having a thinner or narrower pitch.

(Modification 7 of the manufacturing method of the light emitting device)
The manufacturing method of the modified example 7 will be described with reference to FIG. 11 (a). Since the manufacturing process of the modified example 7 is generally the same as that of the above-mentioned modified example 6, the configuration different from the modified example 6 will be described below, and the common configuration will be omitted as appropriate.

In the modified example 7, the conductive layer 24 in the modified example 6 is formed not immediately after the wiring 7g is formed, but after the wiring 7f is formed on the wiring 7g. As a result, as shown in FIG. 11A, the conductive layer 24a covers the periphery of the wiring 7f in addition to the periphery of the wiring 7g excluding the exposed surface of the wiring 7g. With this configuration, the adhesion between the wiring 7f and the wiring 7g can be further enhanced, and the strength can be improved.

(Modification 8 of the manufacturing method of the light emitting device)
The manufacturing method of the modified example 8 will be described with reference to FIG. 11 (b). Since the manufacturing process of the modified example 8 is generally the same as that of the above-mentioned modified example 7, the configuration different from the modified example 7 will be described below, and the common configuration will be omitted as appropriate.

In the modified example 8, after the wirings 7a and 7b are formed in the modified example 7, a metal layer 71 such as copper having a predetermined thickness is formed on the wirings 7a and 7b by electrolytic plating. The thickness of the metal layer 71 is such that the wirings 7a and 7b do not conduct in the XY directions. With this configuration, the electrical resistance of the wiring including the metal layer 71 and the wiring 7a or 7b can be further reduced.

In the modified example 8, the conductive layer 24 of the modified example 6 may be formed instead of the conductive layer 24a. That is, the conductive layer 24 may be formed after the wiring 7g is formed and before the wiring 7f is formed on the wiring 7g.
Further, the formation of the conductive layer 24a and the formation of the metal layer 71 in the modified examples 7 and 8 may also be used in the manufacturing method of the second embodiment using the stainless steel temporary substrate 20 described above. ..

In the various manufacturing methods of the light emitting device 1 and the light emitting device 1 described above, the light emitting unit 3 is not limited to the above configuration. For example, the light emitting unit 3 does not have to have any one or more of the transparent substrate 11, the fluorescent layer 12, and the protective layer 13. For example, when the light emitting unit 3 does not have the protective layer 13, the emission surface of the light emitting unit 3 is the surface on the + Z side of the fluorescent layer 12. Similarly, the injection surface of the light emitting unit 3 can be the surface on the + Z side of the member arranged on the most + Z side among the members constituting the light emitting unit 3.

The substrate 2 is not limited to the rectangular flat plate described above, but may be a flat plate having another shape or a plate-shaped member having a curved surface.
The shape of the injection surface 4 of the light emitting unit 3 is limited to the above-mentioned rectangle, and may be any shape such as a hexagon. Further, the arrangement of the light emitting unit 3 in the substrate 2 is not limited to the arrangement along the X direction and the Y direction described above, and may be any arrangement along other directions.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other aspects conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

1 ... Light emitting device, 2 ... Substrate, 2f ... Front surface, 2b ... Back surface, 3 ... Light emitting part, 4 ... Ejection surface, 5 ... Electrode, 6, 6a to 6d, 6h ... Conductive paste, 7, 7a, 7b, 7e-7h ... Wiring, 8, 8a-8c ... Protective film, 9 ... Resist, 10 ... Light emitting element, 11 ... Transparent substrate, 12 ... Fluorescent layer, 13 ... Protective layer, 20, 21 ... Temporary substrate, 22 ... 1st temporary layer, 23 ... 2nd temporary layer

Claims (18)

To prepare a substrate in which a plurality of light emitting parts are arranged with their emission surfaces facing the front surface, and a plurality of electrodes connected to the plurality of light emitting parts are exposed from the back surface.
Forming wiring using a conductive paste on the back surface of the substrate, which is connected to at least a part of the electrodes.
A method of manufacturing a light emitting device. In the method for manufacturing a light emitting device according to claim 1,
The position information of the electrode formed on the substrate is detected, and the position information is detected.
A method for manufacturing a light emitting device, in which at least a part of the wiring is formed by changing the positional relationship between the wirings based on the position information. In the method for manufacturing a light emitting device according to claim 2,
Based on the position information of the electrode
A part of the wiring is formed by changing the positional relationship between them, and at the same time.
The wiring other than a part of the wiring is formed by fixing the positional relationship between the wirings.
Manufacturing method of light emitting device. In the method for manufacturing a light emitting device according to any one of claims 1 to 3.
The conductive paste is formed on the back surface of the substrate, and the formed conductive paste is sintered to form the wiring on the back surface of the substrate.
Manufacturing method of light emitting device. In the method for manufacturing a light emitting device according to any one of claims 1 to 3.
The conductive paste is formed on the temporary substrate, and the formed conductive paste is sintered to form wiring.
The wiring formed on the temporary substrate is attached to the back surface of the substrate.
A method for manufacturing a light emitting device, in which the temporary substrate is peeled off from the wiring attached to the back surface of the substrate. In the method for manufacturing a light emitting device according to claim 5,
A method for manufacturing a light emitting device, which uses a stainless steel substrate as the temporary substrate. In the method for manufacturing a light emitting device according to claim 5,
A method for manufacturing a light emitting device, which uses a glass substrate as the temporary substrate. In the method for manufacturing a light emitting device according to any one of claims 5 to 7.
A conductive layer is formed on the temporary substrate including the wiring with a conductive material having an etching rate lower than that of the wiring.
A method for manufacturing a light emitting device, in which the conductive layer is etched using the wiring as a mask after peeling the temporary substrate from the wiring. In the method for manufacturing a light emitting device according to any one of claims 4 to 8.
A method for manufacturing a light emitting device, wherein at least a part of the formation of the conductive paste is performed by discharging the conductive paste with a dispenser or an inkjet head. In the method for manufacturing a light emitting device according to claim 4,
The formation of the conductive paste on the back surface of the substrate is
A resist is formed on the back surface of the substrate to form a resist.
A part of the resist is removed to form a groove,
The groove is filled with the conductive paste from which the resist has been removed.
Manufacturing method of light emitting device. In the method for manufacturing a light emitting device according to any one of claims 5 to 8.
The formation of the conductive paste on the temporary substrate is
A resist is formed on the temporary substrate to form a resist.
A part of the resist is removed to form a groove,
The groove is filled with the conductive paste from which the resist has been removed.
Manufacturing method of light emitting device. In the method for manufacturing a light emitting device according to any one of claims 1 to 11.
A method for manufacturing a light emitting device, which uses a substrate containing a resin material as the substrate. The method for manufacturing a light emitting device according to any one of claims 1 to 12.
A method for manufacturing a light emitting device, which forms an insulating layer that covers at least a part of the wiring. The method for manufacturing a light emitting device according to any one of claims 1 to 13.
A method for manufacturing a light emitting device, in which at least a part of the wiring is formed over multiple layers via an insulating layer. The method for manufacturing a light emitting device according to any one of claims 1 to 14.
A method for manufacturing a light emitting device, wherein the thickness of the wiring is 20 μm or less. A substrate in which a plurality of light emitting portions are arranged with their emission surfaces facing the front surface, and a plurality of electrodes connected to the plurality of light emitting portions are exposed from the back surface.
The wiring formed by the conductive paste, which is connected to at least a part of the electrodes,
A light emitting device. In the light emitting device according to claim 16,
A light emitting device having a thickness of 20 μm or less. In the light emitting device according to claim 16,
Including the wiring laminated in four or more layers,
A light emitting device having a thickness of 100 μm or less as a whole of the plurality of laminated wirings.

Images