JP7319551B2 - light emitting device - Google Patents

Description

The present disclosure relates to light emitting devices .

A light emitting device is known in which a plurality of light emitting element portions are connected in series. As an example of such a light emitting device, there is a structure having a series connection body in which at least part of a plurality of light emitting element portions are connected in series. In this light-emitting device, the light-emitting element sections forming the series connection are connected to each other by wires, and the light-emitting element sections forming the series connection are inspected one by one.

JP 2015-126077 A

However, when the chip size is reduced, if all the light emitting element portions are provided with measurement terminals used for inspection, a certain area or more is required to secure the size of the measurement terminals and the spacing between the measurement terminals. Therefore, the area and spacing between the pair of electrodes for external connection have to be reduced, which may lead to a decrease in connection reliability.

Accordingly, an object of the present disclosure is to improve connection reliability of electrodes for external connection in a light-emitting device in which a plurality of light-emitting element units are connected in series.

A light-emitting device according to an embodiment of the present disclosure includes a substrate, and a plurality of light-emitting elements each including a p-type semiconductor layer and an n-type semiconductor layer that are spaced apart from each other and stacked on a first surface of the substrate. a p-electrode disposed on the p-type semiconductor layer and electrically connected to the p-type semiconductor layer, and a p-electrode disposed on the n-type semiconductor layer and the n-type an n-electrode electrically connected to a semiconductor layer, a wiring layer electrically connecting the p-electrode and the n-electrode of the adjacent light-emitting element section, and the light-emitting element section on the most upstream side of the current path. a first electrode made of a metal material different from that of the p-electrode on the p-electrode; a second electrode formed thereon; and a covering member that embeds the p-electrode, the n-electrode, and the wiring layer and exposes the first electrode and the second electrode. , when viewed from the normal direction of the first surface, the area of the first electrode is larger than the area of the n-electrode connected to the wiring layer of the light emitting element section on the most upstream side; The area of the electrode is larger than the area of the p-electrode connected to the wiring layer of the light emitting element portion on the most downstream side, and is connected to the wiring layer when viewed from the normal direction of the first surface. The p-electrode and the n-electrode connected to the wiring layer are arranged obliquely with respect to the first direction in which the adjacent light-emitting element portions are arranged, and when viewed from the normal direction of the first surface, The n-electrode connected to the wiring layer and the first electrode are arranged parallel to a second direction perpendicular to the first direction, and the p-electrode connected to the wiring layer and the first electrode are arranged parallel to the first direction. The second electrode is arranged parallel to the second direction, and when viewed from the normal direction of the first surface, the shape of the first electrode is a rectangle obtained by cutting a rectangle at an angle of 45 degrees, The first electrode is arranged so that the oblique side faces the side of the n-electrode connected to the wiring layer, the shape of the second electrode is a rectangle obtained by cutting a rectangle at an angle of 45 degrees, and the second electrode are arranged such that the oblique side faces the side of the p-electrode connected to the wiring layer .

According to an embodiment of the present disclosure, it is possible to improve connection reliability of electrodes for external connection in a light-emitting device in which a plurality of light-emitting element units are connected in series.

1 is a schematic plan view illustrating a light emitting device according to a first embodiment; FIG. 1 is a schematic cross-sectional view (Part 1) illustrating a light emitting device according to a first embodiment; FIG. FIG. 2 is a schematic cross-sectional view (part 2) illustrating the light emitting device according to the first embodiment; 4A to 4C are diagrams illustrating a method for manufacturing the light emitting device according to the first embodiment; FIG. 4 is a diagram illustrating an equivalent circuit of the light emitting device according to the first embodiment; FIG. FIG. 4 is a schematic plan view illustrating a light emitting device according to modification 1 of the first embodiment; FIG. 4 is a schematic cross-sectional view (Part 1) illustrating a light-emitting device according to Modification 1 of the first embodiment; FIG. 2 is a schematic cross-sectional view (Part 2) illustrating a light-emitting device according to Modification 1 of the first embodiment; FIG. 11 is a schematic plan view (Part 1) illustrating a light-emitting device according to Modification 2 of the first embodiment; FIG. 10 is a schematic cross-sectional view (part 1) illustrating a light-emitting device according to Modification 2 of the first embodiment; FIG. 10 is a schematic cross-sectional view (part 2) illustrating a light-emitting device according to Modification 2 of the first embodiment; FIG. 10 is a diagram (part 1) illustrating an equivalent circuit of a light-emitting element according to modification 2 of the first embodiment; FIG. 10 is a schematic plan view (part 2) illustrating a light-emitting device according to Modification 2 of the first embodiment; FIG. 10 is a diagram (part 2) illustrating an equivalent circuit of a light-emitting element according to modification 2 of the first embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the following description, terms indicating specific directions and positions (e.g., "upper", "lower", and other terms including those terms) are used as necessary, but the use of these terms is These terms are used to facilitate understanding of the invention with reference to the drawings, and the technical scope of the invention is not limited by the meaning of these terms. Also, parts with the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members.

Furthermore, the embodiments shown below are examples of light-emitting devices for embodying the technical idea of the present invention, and the present invention is not limited to the following. In addition, unless there is a specific description, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention, but are intended to be illustrative. It is intended. Moreover, the content described in one embodiment can also be applied to other embodiments and modifications. Also, the sizes and positional relationships of members shown in the drawings may be exaggerated for clarity of explanation.

<First Embodiment>
(Light emitting device 1)
FIG. 1 is a schematic plan view illustrating the light emitting device according to the first embodiment. FIG. 2 is a schematic cross-sectional view illustrating the light-emitting device according to the first embodiment, showing a cross-section taken along line AA of FIG. FIG. 3 is a schematic cross-sectional view illustrating the light emitting device according to the first embodiment, showing a cross section along line BB in FIG.

As shown in FIGS. 1 to 3, the light emitting device 1 has a light emitting element 10 and a covering member 20. As shown in FIG. The light-emitting element 10 includes a substrate 11, a light-emitting element portion 12, a light-emitting element portion 13, a p-electrode 121, an n-electrode 122, a p-electrode 131, an n-electrode 132, a first electrode 123, and a second electrode. 133. The light emitting element portions 12 and 13 each include a semiconductor laminate 14 and an insulating layer 16 .

The substrate 11 has a first surface 11a (upper surface in FIGS. 2 and 3) and a second surface 11b (lower surface in FIGS. 2 and 3) opposite to the first surface 11a. . The first surface 11a and the second surface 11b of the substrate 11 have, for example, a substantially square shape when viewed from the normal direction of the first surface 11a, but the shape is not limited to this. When the first surface 11a and the second surface 11b of the substrate 11 are substantially square, the length of one side can be, for example, approximately 500 μm.

The substrate 11 is a member that supports the semiconductor laminate 14 and the like. Also, the substrate 11 may be a growth substrate for epitaxially growing the semiconductor laminate 14 . As the substrate 11, for example, when a nitride-based semiconductor is used for the semiconductor laminate 14, a sapphire ( _{Al2O3 )} substrate can be used. In the light emitting element 10 , light is mainly extracted from the second surface 11 b of the substrate 11 . As described above, the light emitting device 1 has a CSP (Chip Size Package) structure in which light is extracted from the second surface 11 b side of the substrate 11 .

Note that the normal direction of the first surface 11a of the substrate 11 is the Z direction, the direction in which the light emitting element portions 12 and 13 are arranged in the plane perpendicular to the Z direction is the X direction, and the X direction and the Z direction are the directions. Let the vertical direction be the Y direction. In the following description, the term "planar view" means viewing an object from the direction normal to the first surface 11a of the substrate 11, and the term "planar shape" means viewing the object from the direction normal to the first surface 11a of the substrate 11. It shall refer to the shape viewed from

The light emitting element portions 12 and 13 are formed by laminating a p-type semiconductor layer and an n-type semiconductor layer forming a part of the semiconductor laminate 14 on the substrate 11, separating them in the plane, and connecting them in series with each other through the wiring layer 17. It is connected. In the semiconductor laminate 14 , for example, an n-type semiconductor layer and a p-type semiconductor layer are laminated in order from the first surface 11 a side of the substrate 11 . For example, a light emitting layer is provided between the p-type semiconductor layer and the n-type semiconductor layer.

When the light-emitting element 10 emits blue or green light, the n-type semiconductor layer, the p-type semiconductor layer, and the light-emitting layer in the semiconductor laminate 14 may be, for example, a nitride-based semiconductor (In _X Al _Y Ga _{1- XYN} , 0≤X, 0≤Y, X+Y≤1) and GaP can be used. Further, when the light emitting element 10 emits red light, a semiconductor such as GaAlAs or AlInGaP can be used. By changing the material of the semiconductor laminate 14 and its mixed crystal ratio, the emission wavelength can be changed.

The insulating layer 16 is provided, for example, above the p-type semiconductor layer and the n-type semiconductor layer of the semiconductor laminate 14 (on the side away from the first surface 11a). As the insulating layer 16, for example, an oxide or nitride containing at least one selected from the group consisting of Si, Ti, Zr, Nb, Ta, Al, and Hf can be used.

Although the insulating layer 16 is illustrated in a simplified manner in FIGS. 2 and 3, the insulating layer 16 is formed in a predetermined pattern so that the p-type semiconductor layer and the n-type semiconductor layer of the semiconductor laminate 14 and light emission The element portions 12 and 13 are electrically insulated from necessary portions. In FIGS. 2 and 3, the substrate 11, the semiconductor laminate 14, and the insulating layer 16 on the semiconductor laminate side are drawn flat, but they may be uneven.

The p-electrode 121 is formed in the opening of the insulating layer 16 and electrically connected to the p-type semiconductor layer of the semiconductor laminate 14 forming the light emitting element section 12 . The n-electrode 122 is formed in the opening of the insulating layer 16 and electrically connected to the n-type semiconductor layer of the semiconductor laminate 14 forming the light-emitting element section 12 . For example, the light-emitting element section 12 is a light-emitting diode, the p-electrode 121 is an anode electrode, and the n-electrode 122 is a cathode electrode.

The p-electrode 131 is formed in the opening of the insulating layer 16 and electrically connected to the p-type semiconductor layer of the semiconductor laminate 14 forming the light-emitting element section 13 . The n-electrode 132 is formed in the opening of the insulating layer 16 and electrically connected to the n-type semiconductor layer of the semiconductor laminate 14 forming the light-emitting element portion 13 . For example, the light-emitting element section 13 is a light-emitting diode, the p-electrode 131 is an anode electrode, and the n-electrode 132 is a cathode electrode.

As the p-electrode 121, the n-electrode 122, the p-electrode 131, and the n-electrode 132, for example, a metal material such as Ag, Al, or an alloy thereof having good conductivity and light reflectivity can be used. For example, the p-electrode 121, the n-electrode 122, the p-electrode 131, and the n-electrode 132 are electrically connected to the measuring device in an electrical property inspection performed before the covering member 20 is formed in the manufacturing process of the light emitting device 1. Can be used as a measurement terminal connected to

A first electrode 123 is formed on the p-electrode 121 and a second electrode 133 is formed on the n-electrode 132 . At least the upper surfaces of the first electrode 123 and the second electrode 133 are exposed from the covering member 20 and can be used as electrodes for external connection, for example. The first electrode 123 and the second electrode 133 are used, for example, as electrodes for external connection, and are used in the electrical property inspection performed before forming the covering member 20 in the manufacturing process of the light emitting device 1. You may use it as a terminal for a measurement electrically connected with. For the first electrode 123 and the second electrode 133, for example, metal materials such as Cu, Cu alloys, Au, Ag, Ni, and Zn, which have good conductivity and solder wettability, can be used.

The n-electrode 122 connected to the light emitting element section 12 is electrically connected through the wiring layer 17 to the p-electrode 131 connected to the light emitting element section 13 . That is, the light emitting element section 12 and the light emitting element section 13 are connected in series with each other through the wiring layer 17 (see FIG. 5 described later). As the wiring layer 17, for example, a metal material such as Ag, Al, or an alloy thereof having good conductivity and light reflectivity can be used.

This wiring layer 17 can be integrated with the n-electrode 122 and the p-electrode 131 . The semiconductor laminate 14 forming the light emitting element section 12 and the semiconductor laminate 14 forming the light emitting element section 13 are connected via a wiring layer provided between the n-electrode 122 and the semiconductor laminate 14. Alternatively, they may be connected via a wiring layer provided between the p-electrode 131 and the semiconductor laminate 14 . Also, any wiring layer may be used as long as it electrically connects at least the light emitting element section 12 and the light emitting element section 13 .

The light emitting element portions 12 and 13 can be formed, for example, in an elongated shape with the Y direction as the longitudinal direction. In this case, the p-electrode 121 and the n-electrode 122 can be arranged parallel to the Y direction, for example. Similarly, the p-electrode 131 and the n-electrode 132 can be arranged parallel to the Y direction, for example. The distance between the p-electrode 121 and the p-electrode 131 and the distance between the n-electrode 122 and the n-electrode 132 can be, for example, about 200 μm.

Also, the p-electrode 121 and the n-electrode 132 can be arranged, for example, diagonally with respect to the X direction (for example, so that both are positioned in a direction that is 45 degrees counterclockwise with respect to the X direction). Also, the n-electrode 122 and the p-electrode 131 can be arranged, for example, diagonally with respect to the X direction (for example, so that both are positioned in a direction 45 degrees clockwise with respect to the X direction).

The covering member 20 covers part of the light emitting element 10 . Specifically, the covering member 20 has a surface on which the p-electrode 121 and the n-electrode 122 of the light-emitting element section 12 are formed, and a surface on which the p-electrode 131 and the n-electrode 132 of the light-emitting element section 13 are formed. is covered at least. Alternatively, the covering member 20 may cover the side surface of the substrate 11 and expose the second surface 11b.

The covering member 20 also embeds the p-electrode 121 and n-electrode 122 of the light-emitting element section 12 and the p-electrode 131 and n-electrode 132 of the light-emitting element section 13 . In addition, the covering member 20 covers the side surfaces of the first electrode 123 and the side surfaces of the second electrode 133 and exposes the upper surface of the first electrode 123 and the upper surface of the second electrode 133 . A portion of the side surface of the first electrode 123 and a portion of the side surface of the second electrode 133 may be exposed from the covering member 20 .

The covering member 20 is made of a material having excellent light reflectivity, and is preferably a white resin obtained by adding white powder or the like, which is an additive that reflects light, to a transparent resin. White resin having a reflectance of 60% or more, preferably 90% or more, with respect to the light emitted from the light emitting element 10 is suitable for the covering member 20 . The covering member 20 is preferably made of a resin containing a white pigment such as white powder as a light reflecting material. In particular, a silicone resin containing inorganic white powder such as titanium oxide is preferred. Since the coating member 20 contains the resin containing the light reflecting material, the light absorption loss can be reduced by suppressing the leakage of light.

The planar shape of the covering member 20 is, for example, a substantially square shape, but is not limited thereto. When the planar shape of the covering member 20 is substantially square, the length of one side can be set to, for example, about 1000 μm.

The area of the first electrode 123 that can be used as an electrode for external connection is larger than the area of the n-electrode 122 that is used as a terminal for measurement and finally embedded in the covering member 20 . Also, the area of the second electrode 133 that can be used as an electrode for external connection is larger than the area of the p-electrode 131 that is used as a terminal for measurement and finally embedded in the covering member 20 .

The planar shapes of the n-electrode 122 and the p-electrode 131 are, for example, quadrangular (for example, square). The area of the n-electrode 122 and the area of the p-electrode 131 are substantially the same.

The planar shape of the p-electrode 121 and the first electrode 123 is, for example, a rectangle obtained by cutting a rectangle obliquely at an angle of 45 degrees, and is arranged so that the oblique side faces the n-electrode 122 side. Similarly, the planar shape of the n-electrode 132 and the second electrode 133 is, for example, a rectangle obtained by cutting a rectangle at an angle of 45 degrees, and the oblique sides are arranged so as to face the p-electrode 131 side. The area of the first electrode 123 and the area of the second electrode 133 are substantially the same.

By making the shape and arrangement of the first electrode 123 and the second electrode 133 as shown in FIG. The area of the upper surface can be further increased.

In the light-emitting device 1, light is mainly extracted from the second surface 11b side of the substrate 11, but the second surface 11b of the substrate 11 also absorbs part of the light having the wavelength emitted by the light-emitting element portion. It may have a wavelength conversion layer containing wavelength conversion members that emit light of different wavelengths.

(Manufacturing method of light-emitting device 1)
A method for manufacturing the light emitting device 1 according to the first embodiment will be described with reference to FIG. 4A and 4B are diagrams illustrating the method for manufacturing the light emitting device according to the first embodiment, showing a cross section corresponding to FIG. 4A to 4C show the process of forming the light emitting element 10, and FIG. 4D shows the process of forming the covering member 20 that partially covers the light emitting element 10. FIG.

First, as shown in FIG. 4A, a semiconductor laminate 14 including a p-type semiconductor layer and an n-type semiconductor layer separated in the plane is formed on a substrate 11, and a plurality of light emitting element portions 12 and 13 are formed. to form Furthermore, an insulating layer 16 is formed.

That is, for example, a sapphire substrate is used as the substrate 11, and a nitride-based semiconductor semiconductor laminate 14 including a p-type semiconductor layer, an n-type semiconductor layer, and a light-emitting layer is crystal-grown on the first surface 11a of the substrate 11, In-plane separation. Then, the insulating layer 16 having a predetermined pattern is formed in a predetermined region on the semiconductor laminate 14 by, for example, combining the sputtering method and dry etching.

Next, as shown in FIG. 4B, in the light emitting element portions 12 and 13, a p-electrode electrically connected to the p-type semiconductor layer and an n-electrode electrically connected to the n-type semiconductor layer are formed. Form.

That is, a p-electrode 121 electrically connected to the p-type semiconductor layer of the light emitting element portion 12 and an n-electrode 122 electrically connected to the n-type semiconductor layer of the light emitting element portion 12 are formed in the openings of the insulating layer 16 by sputtering or the like. Form into a predetermined shape. Further, a p-electrode 131 electrically connected to the p-type semiconductor layer of the light emitting element portion 13 and an n-electrode 132 electrically connected to the n-type semiconductor layer of the light emitting element portion 13 are formed in the openings of the insulating layer 16 by sputtering or the like. Form into a predetermined shape. Thus, the p-electrodes and n-electrodes are electrically connected to the p-type semiconductor layer and n-type semiconductor layer of the semiconductor laminate 14 through the openings provided in the insulating layer 16 .

Further, a wiring layer 17 for electrically connecting the n-electrode 122 and the p-electrode 131 is formed in a predetermined pattern on the insulating layer 16 by sputtering or the like. As a result, the light emitting element section 12 and the light emitting element section 13 are connected in series with each other via the wiring layer 17 . However, even if the wiring layer 17 is not formed and the wiring layer provided between the p-electrode 131 and the light emitting element section 13 is electrically connected between the n electrode 122 and the light emitting element section 12 . good.

At this point, a light emitting device having an equivalent circuit as shown in FIG. 5(a) is obtained. Using the p-electrode 121, the n-electrode 122, the p-electrode 131, and the n-electrode 132 as terminals for measurement, and supplying power to each electrode, the electrical characteristics of the light-emitting element section 12 and the light-emitting element section 13 can be independently inspected (p between the electrode 121 and the n-electrode 122, and between the p-electrode 131 and the n-electrode 132, respectively). The inspection of electrical characteristics referred to here is, for example, measurement of leakage current. A light emission test or the like may be performed as necessary.

Next, as shown in FIG. 4C, a first electrode 123 is formed on the p-electrode 121 of the light-emitting element portion 12 on the most upstream side of the current path by sputtering or the like, and the first electrode 123 is formed on the most downstream side of the current path. A second electrode 133 is formed on the n-electrode 132 of the light emitting element section 13 . The light emitting device 10 is obtained through the above steps.

At this point, a light emitting device having an equivalent circuit as shown in FIG. 5B is obtained. By using the first electrode 123, the n-electrode 122, the p-electrode 131, and the second electrode 133 as terminals for measurement and supplying power to each electrode, the electrical characteristics of the light-emitting element section 12 and the light-emitting element section 13 can be independently inspected. (The test is performed between the p-electrode 121 and the n-electrode 122, and between the p-electrode 131 and the n-electrode 132, respectively). The step of inspecting the electrical characteristics may be performed before the step of forming the first electrode 123 and the second electrode 133, may be performed after the step of forming the first electrode 123 and the second electrode 133, or may be performed at both.

Next, as shown in FIG. 4(d), a covering member 20 is formed in which the p-electrode 121, the n-electrode 122, the p-electrode 131 and the n-electrode 132 are embedded and the first electrode 123 and the second electrode 133 are exposed. do. Specifically, for example, the covering member 20 is formed by compression molding using a mold so as to embed the p-electrode 121, the n-electrode 122, the p-electrode 131, the n-electrode 132, the first electrode 123, and the second electrode 133. After that, the covering member 20 may be polished by mechanical polishing or sandblasting until the upper surfaces of the first electrode 123 and the second electrode 133 are exposed. Alternatively, the covering member 20 may be formed by cast molding so that the covering member is not formed on the second surface 11 b of the substrate, the first electrode 123 and the second electrode 133 .

In addition, in the step of forming the covering member 20, it is preferable to cover the surface of each light emitting element portion on the side where the p-electrode and the n-electrode are formed. Also, the covering member 20 preferably contains a resin containing a light reflecting material. Through the steps described above, the light-emitting device 1 in which a predetermined portion of the light-emitting element 10 is covered with the covering member 20 is obtained.

As described above, in the light emitting device according to the present embodiment, each of the plurality of light emitting element units connected in series is provided with the p-electrode and the n-electrode that can be used as terminals for measurement. Electrical characteristics can be inspected for each light emitting element portion. As a result, it is possible to prevent a light-emitting device having a defect in a part of the light-emitting element portions from flowing out to the post-process, causing problems such as non-lighting and dark lighting.

By the way, the p-electrode and the n-electrode of the adjacent light-emitting element portions are connected in series, and this connection can be made by exposing the p-electrode and the n-electrode from the light-emitting device and by wiring provided outside the light-emitting device. Conceivable. However, in this case, it is necessary to increase the areas of the p-electrode and the n-electrode to some extent and to increase the gap between the p-electrode and the n-electrode, which leads to an increase in the size of the light emitting device.

On the other hand, in the light-emitting device according to the present embodiment, the p-electrode and the n-electrode of the adjacent light-emitting element portions are connected in series in the inner layer of the light-emitting device. becomes possible, and the light-emitting device can be miniaturized.

Further, in the light emitting device according to this embodiment, since a plurality of light emitting element portions are connected in series, a light emitting device having a high forward voltage can be realized. As a result, the current supplied from the power supply side connected to the light emitting device can be reduced. That is, a small power supply can be used.

In addition, since the p-electrode and the n-electrode are insulated by being embedded in the covering member when the light-emitting device is obtained, there is no fear of short-circuiting each other even if the gap between the p-electrode and the n-electrode is made small. There is no risk of short-circuiting between the n-electrode and the first or second electrode.

Moreover, since the surface of each light emitting element portion on which the p-electrode and the n-electrode are formed is covered with the covering member, a highly reliable light emitting device can be realized.

In addition, in the light emitting device according to the present embodiment, by devising the shapes of the first electrode and the second electrode, the area of the first electrode and the second electrode exposed from the covering member can be increased. It is possible to improve the joint strength and connection reliability of the joint (solder or the like) between the two electrodes and the object to be connected. In addition, by increasing the area of the first electrode and the second electrode, the electrical resistance of the first electrode and the second electrode can be reduced, and the heat dissipation from the first electrode and the second electrode can be improved.

<Modification 1 of the first embodiment>
Modification 1 of the first embodiment shows an example in which a metal film is formed on a covering member. In addition, in Modification 1 of the first embodiment, the description of the same components as those of the already described embodiment may be omitted.

FIG. 6 is a schematic plan view illustrating a light-emitting device according to modification 1 of the first embodiment. FIG. 7 is a schematic cross-sectional view illustrating a light-emitting device according to Modification 1 of Embodiment 1, showing a cross-section taken along line CC of FIG. FIG. 8 is a schematic cross-sectional view illustrating a light-emitting device according to Modification 1 of Embodiment 1, showing a cross-section taken along line DD of FIG.

As shown in FIGS. 6 to 8, the light emitting device 1A differs from the light emitting device 1 (see FIGS. 1 to 3) in that the first metal film 124 and the second metal film 134 are formed on the covering member 20. differ.

The first metal film 124 is electrically connected to the first electrode 123 . Also, the second metal film 134 is electrically connected to the second electrode 133 . The first metal film 124 and the second metal film 134 can be formed, for example, by sputtering copper. The first metal film 124 and the second metal film 134 may be formed of, for example, gold, silver, nickel, zinc, etc. other than copper, or may be formed by plating copper. In plan view, the area of the first metal film 124 is larger than the area of the first electrode 123 , and the area of the second metal film 134 is larger than the area of the second electrode 133 .

The step of forming the first metal film 124 electrically connected to the first electrode 123 and the second metal film 134 electrically connected to the second electrode 133 on the covering member 20 is shown in FIG. can be provided after the step of

In this way, by providing the first metal film 124 and the second metal film 134 on the covering member 20 and using them as electrodes for external connection, the first electrode 123 and the second electrode 133 are used as electrodes for external connection. A larger area that can be used for connection can be obtained than in the case of the case. Therefore, the bonding strength and connection reliability of the bonding portion between the first metal film 124 or the second metal film 134 and the object to be connected are increased compared to the case where the first electrode 123 and the second electrode 133 are used as terminals for external connection. It can be improved further. Moreover, compared to the case where the first electrode 123 and the second electrode 133 are used as terminals for external connection, the electrical resistance of the first metal film 124 and the second metal film 134 can be reduced. Heat dissipation from the metal film 134 can be improved.

In plan view, the first metal film 124 preferably covers at least a portion of the first electrode 123 and extends over the n-electrode 122 embedded in the covering member 20 . Also, the second metal film 134 preferably covers at least a portion of the second electrode 133 and extends over the p-electrode 131 embedded in the covering member 20 . Thereby, the areas of the first metal film 124 and the second metal film 134 can be made larger.

In plan view, the first metal film 124 preferably covers the entire first electrode 123 and extends over the n-electrode 122 embedded in the covering member 20 . Also, the second metal film 134 preferably covers the entire second electrode 133 and extends over the p-electrode 131 embedded in the covering member 20 . Thereby, the areas of the first metal film 124 and the second metal film 134 can be particularly increased.

<Modification 2 of the first embodiment>
Modification 2 of the first embodiment shows an example in which the shapes and arrangements of the p-electrode and the n-electrode are different from those of the first embodiment. In addition, in the modification 2 of the first embodiment, the description of the same components as those of the already described embodiment may be omitted.

FIG. 9 is a schematic plan view illustrating a light-emitting device according to modification 2 of the first embodiment. FIG. 10 is a schematic cross-sectional view illustrating a light-emitting device according to Modification 2 of Embodiment 1, showing a cross-section taken along line EE of FIG. FIG. 11 is a schematic cross-sectional view illustrating a light-emitting device according to Modification 2 of Embodiment 1, showing a cross-section taken along line FF of FIG.

As shown in FIGS. 9 to 11, the light emitting device 1B has a p-electrode 121B, an n-electrode 122B, a p-electrode 131B, an n-electrode 132B, a first electrode 123B, and a second electrode 133B. , is different from the light emitting device 1 (see FIGS. 1 to 3).

The p-electrode 121B and the n-electrode 122B can be arranged parallel to the Y direction, for example. Similarly, the p-electrode 131B and the n-electrode 132B can be arranged parallel to the Y direction, for example. The distance between the p-electrode 121B and the n-electrode 132B and the distance between the n-electrode 122B and the p-electrode 131B can be, for example, about 200 μm.

Also, the p-electrode 121B and the n-electrode 132B can be arranged parallel to the X direction, for example. Also, the n-electrode 122B and the p-electrode 131B can be arranged parallel to the X direction, for example. The n-electrode 122B is electrically connected through the wiring layer 17 to the p-electrode 131B. That is, as shown in FIG. 12, the light emitting element section 12 and the light emitting element section 13 are connected in series with each other via the wiring layer 17 .

The covering member 20 embeds the p-electrode 121B and n-electrode 122B of the light-emitting element section 12 and the p-electrode 131B and n-electrode 132B of the light-emitting element section 13 . The covering member 20 covers the side surfaces of the first electrode 123B and the side surface of the second electrode 133B, and exposes the upper surface of the first electrode 123B and the upper surface of the second electrode 133B. A portion of the side surface of the first electrode 123B and a portion of the side surface of the second electrode 133B may be exposed from the covering member 20 .

The areas of the first electrode 123B and the second electrode 133B that can be used as electrodes for external connection are larger than the areas of the n-electrode 122B and the p-electrode 131B that are used as terminals for measurement and finally embedded in the covering member 20. .

The planar shapes of the n-electrode 122B and the p-electrode 131B are, for example, squares. The planar shapes of the p-electrode 121B and first electrode 123B, and the n-electrode 132B and second electrode 133B are rectangular, for example.

Thus, the shape and arrangement of the first electrode and the second electrode are not limited to the form shown in FIG. 1, and may be the form shown in FIG. Also in this case, the same effects as in the first embodiment are obtained.

Further, as shown in FIG. 13, the number of light emitting element units connected in series is not limited to two, and may be any number of three or more. As an example, a light emitting device 1C shown in FIG. 13 includes a light emitting element portion 18 in which a p-electrode 181 and an n-electrode 182 are formed between the light emitting element portions 12 and 13 of the light emitting device 1B shown in FIG. Four of them are arranged in the X direction, and as a whole, six light emitting element portions are connected in series as shown in FIG. The first electrode 123B is formed on the p-electrode 121B of the light-emitting element section 12 on the most upstream side of the current path, and the second electrode 133B is formed on the n-electrode 132B of the light-emitting element section 13 on the most downstream side of the current path. ing.

Thus, by increasing the number of light emitting element units connected in series, a light emitting device with a higher forward voltage can be realized. As a result, the current supplied from the power supply side connected to the light emitting device can be further reduced. Thus, a smaller power supply can be used.

Even if the number of light-emitting element units connected in series is increased, each light-emitting element unit has a p-electrode and an n-electrode. Properties can be independently inspected.

Although the preferred embodiments and the like have been described in detail above, the present invention is not limited to the above-described embodiments and the like, and various modifications and substitutions can be made to the above-described embodiments and the like without departing from the scope of the claims. can be added.

1, 1A, 1B, 1C light-emitting device 10 light-emitting element 11 substrate 11a first surface 11b second surface 12, 13, 18 light-emitting element portion 14 semiconductor laminate 17 wiring layer 16 insulating layer 20 covering member 121, 121B, 131, 131B , 181 p-electrodes 122, 122B, 132, 132B, 182 n-electrodes 123, 123B first electrode 124 first metal films 133, 133B second electrode 134 second metal film

Claims (6)

a substrate;
a plurality of light emitting device units each including a stacked p-type semiconductor layer and an n-type semiconductor layer spaced apart from each other on the first surface of the substrate;
In each of the light emitting element portions, a p-electrode disposed on the p-type semiconductor layer and electrically connected to the p-type semiconductor layer, and a p-electrode disposed on the n-type semiconductor layer and the n-type semiconductor layer and an electrically connected n-electrode;
a wiring layer electrically connecting the p-electrode and the n-electrode of the adjacent light emitting element portions;
a first electrode formed of a metal material different from that of the p-electrode on the p-electrode of the light-emitting element section on the most upstream side of the current path;
a second electrode formed of a metal material different from that of the n-electrode on the n-electrode of the light-emitting element portion on the most downstream side of the current path;
a light-emitting element comprising
a covering member that embeds the p-electrode, the n-electrode, and the wiring layer and exposes the first electrode and the second electrode;
Viewed from the normal direction of the first surface,
The area of the first electrode is larger than the area of the n-electrode connected to the wiring layer of the light emitting element section on the most upstream side,
The area of the second electrode is larger than the area of the p-electrode connected to the wiring layer of the light-emitting element portion on the most downstream side,
When viewed from the normal direction of the first surface, the p-electrode connected to the wiring layer and the n-electrode connected to the wiring layer are arranged in the first direction in which the adjacent light emitting element portions are arranged. placed diagonally with respect to
Viewed from the normal direction of the first surface,
the n-electrode and the first electrode connected to the wiring layer are arranged parallel to a second direction orthogonal to the first direction,
the p-electrode and the second electrode connected to the wiring layer are arranged parallel to the second direction,
Viewed from the normal direction of the first surface,
The shape of the first electrode is a rectangle obtained by cutting a rectangle at an angle of 45 degrees, and the first electrode is arranged so that the oblique side of the first electrode faces the side of the n-electrode connected to the wiring layer,
The shape of the second electrode is a rectangle obtained by cutting a rectangle at an angle of 45 degrees, and the oblique side of the second electrode is arranged to face the p-electrode connected to the wiring layer. 2. The light-emitting device according to claim 1 , wherein the covering member covers the surface of each of the light-emitting element portions on which the p-electrode and the n-electrode are formed. 3. The light emitting device according to claim 2 , wherein the covering member contains a resin containing a light reflecting material. a first metal film electrically connected to the first electrode and a second metal film electrically connected to the second electrode are formed on the covering member;
Viewed from the normal direction of the first surface,
The area of the first metal film is larger than the area of the first electrode,
4. The light emitting device according to claim 1 , wherein the area of the second metal film is larger than the area of the second electrode. Viewed from the normal direction of the first surface,
the first metal film covers at least a portion of the first electrode and extends over the n-electrode embedded in the covering member of the light emitting element section on the most upstream side;
5. The light-emitting device according to claim 4 , wherein the second metal film covers at least part of the second electrode and extends over the p-electrode embedded in the covering member of the light-emitting element portion on the most downstream side. . Viewed from the normal direction of the first surface,
The first metal film covers the entire first electrode,
6. The light emitting device according to claim 5 , wherein the second metal film covers the entire second electrode.

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