JP2024041498A - Wiring board, light emitting device and manufacturing method thereof - Google Patents

Abstract

[Problem] To provide a wiring board, a light emitting device, and a manufacturing method thereof that can improve heat dissipation and light reflectance. [Solution] A manufacturing method S10 for a wiring board includes the steps of preparing a metal plate having a first surface with a plurality of convex portions spaced apart from each other and a second surface opposite to the first surface, forming a metal oxide layer S12 on the first surface of the metal plate, arranging an uncured inorganic light reflective member on the first surface of the metal plate on which the metal oxide layer has been formed S13, curing the arranged light reflective member S14, removing a part of the cured light reflective member S15, exposing the base metal of the metal plate on the upper surface of the convex portions by removing a part of the light reflective member S16, removing a part of the second surface side of the metal plate S17, and removing a part of the second surface side of the metal plate S18 to expose the light reflective member between adjacent metal blocks. [Selected Figure] Figure 2

Description

The present disclosure relates to a wiring board, a light emitting device, and a manufacturing method thereof.

BACKGROUND ART Conventionally, a laminated ceramic electronic component is known that includes a laminate including a plurality of laminated ceramic layers and a conductive wiring layer formed on the ceramic layer (for example, see Patent Document 1). This conductive wiring layer is made of metal foil or metal wire, and at least a portion of its surface is covered with at least _one selected from Cr, Mo, Ti, _Al2O3 , and the like. Moreover, the metal foil or metal wire contains at least one selected from Cu, Ag, Au, and the like. Furthermore, this manufacturing method includes the step of covering at least a portion of the surface of the metal foil or metal wire with at least one member selected from Cu ₂ O, Cr, Mo, Ti, Al ₂ O ₃ and the like.

Japanese Patent Application Publication No. 2004-55728

The objective of the present disclosure is to provide a wiring board, a light-emitting device, and a method for manufacturing the same that can improve heat dissipation and light reflectance.

A method for manufacturing a wiring board disclosed in the embodiment includes preparing a metal plate having a first surface having a plurality of convex portions spaced apart from each other and a second surface opposite to the first surface; forming a metal oxide layer on the first surface of the metal plate; disposing an uncured inorganic light-reflecting member on the first surface of the metal plate on which the metal oxide layer is formed; By curing the disposed light-reflecting member, removing a portion of the cured light-reflecting member, and removing a portion of the light-reflective member, the upper surface of the convex portion is coated. By exposing the metal of the base material of the metal plate, by removing a part of the second surface side of the metal plate, and by removing a part of the second surface side of the metal plate, exposing the light reflective member between adjacent metal blocks.

A method for manufacturing a light emitting device disclosed in an embodiment includes preparing a wiring board manufactured by a method for manufacturing a wiring board disclosed in an embodiment, and including a light emitting element having a pair of element electrodes on the wiring board. arranging a plurality of light sources, and in arranging the light sources, each of the pair of element electrodes is connected to each of the adjacent metal blocks via a conductive member.

The wiring board disclosed in the embodiment has an upper surface, a lower surface opposite to the upper surface, and a side surface continuous with the upper surface and the lower surface, and is spaced apart in at least one of the row and column directions. a plurality of metal blocks, and an inorganic light-reflecting member disposed on the side surface of the metal block and forming a flat plate together with the metal blocks, the side surface of the metal block facing the light-reflective member. A metal oxide layer is disposed on the surface.

A light emitting device disclosed in an embodiment includes a wiring board disclosed in an embodiment, and a light source including a light emitting element disposed on an upper surface of the wiring board and having a pair of element electrodes. Each of the metal blocks is connected to each of the adjacent metal blocks via a conductive member.

According to embodiments of the present disclosure, it is possible to provide a wiring board, a light emitting device, and a manufacturing method thereof that can improve heat dissipation and light reflectance.

FIG. 1 is a plan view schematically illustrating a wiring board according to an embodiment. 1A is a sectional view taken along line IB-IB in FIG. 1A. FIG. FIG. 1 is a perspective view schematically illustrating a metal block according to an embodiment. 1 is a flowchart illustrating a method for manufacturing a wiring board according to an embodiment. FIG. 2 is a cross-sectional view illustrating a flat plate that is a material of a metal plate to be prepared in a method for manufacturing a wiring board according to an embodiment. FIG. 2 is a cross-sectional view illustrating a state in which a mask is formed on a flat plate in the method for manufacturing a wiring board according to an embodiment. FIG. 3 is a cross-sectional view illustrating a state in which a convex portion is formed by etching in the method for manufacturing a wiring board according to an embodiment. FIG. 3 is a cross-sectional view illustrating a prepared metal plate in the method for manufacturing a wiring board according to the embodiment. FIG. 2 is a cross-sectional view illustrating a state in which a metal oxide layer is formed on a metal plate in a method for manufacturing a wiring board according to an embodiment. FIG. 2 is a cross-sectional view illustrating a state in which a light reflective member is formed on a metal plate in a method for manufacturing a wiring board according to an embodiment. FIG. 3 is a cross-sectional view illustrating a state in which a part of the light reflective member is removed to expose the metal of the base material of the metal plate in the method for manufacturing a wiring board according to the embodiment. FIG. 3 is a cross-sectional view illustrating a state in which a part of the metal plate is removed to expose a light reflective member between adjacent metal blocks in the method for manufacturing a wiring board according to the embodiment. FIG. 7 is a cross-sectional view illustrating a flat plate that is a material of a metal plate to be prepared in a modification of the method for manufacturing a wiring board. FIG. 7 is a cross-sectional view illustrating a state in which a dry film is arranged on a flat plate in a modification of the method for manufacturing a wiring board. FIG. 7 is a cross-sectional view illustrating a state in which a mask is formed on a flat plate in a modification of the method for manufacturing a wiring board. FIG. 7 is a cross-sectional view illustrating a state in which a convex portion is formed by plating in a modification of the method for manufacturing a wiring board. FIG. 7 is a cross-sectional view illustrating a prepared metal plate in a modification of the method for manufacturing a wiring board. 1 is a plan view illustrating an outline of a light emitting device according to a first embodiment. 5A is a cross-sectional view taken along the line VB-VB in FIG. 5A. FIG. 1 is a plan view schematically illustrating a light source of a light emitting device according to an embodiment. FIG. 2 is a bottom view schematically illustrating a light source of a light emitting device according to an embodiment. 6A is a cross-sectional view taken along the line VIC-VIC in FIG. 6A. FIG. 4 is a flowchart illustrating a method for manufacturing the light emitting device according to the first embodiment. FIG. 2 is a cross-sectional view illustrating a prepared metal plate in the method for manufacturing a light emitting device according to the first embodiment. FIG. 2 is a cross-sectional view illustrating a state in which a plating layer is formed on the surface of a metal block in the method for manufacturing a light emitting device according to the first embodiment. FIG. 2 is a cross-sectional view illustrating a state in which a light source is arranged on a wiring board in the method for manufacturing a light emitting device according to the first embodiment. FIG. 7 is a plan view schematically illustrating a light emitting device according to a second embodiment. 9A is a cross-sectional view taken along line IXB-IXB in FIG. 9A. FIG. FIG. 7 is a cross-sectional view schematically illustrating a singulated light emitting device according to a second embodiment. 7 is a flowchart illustrating a method for manufacturing a light emitting device according to a second embodiment. FIG. 7 is a cross-sectional view illustrating a state in which light emitting elements are arranged in a method for manufacturing a light emitting device according to a second embodiment. FIG. 7 is a cross-sectional view illustrating a state in which a light-transmitting member is arranged in a method for manufacturing a light-emitting device according to a second embodiment. FIG. 7 is a cross-sectional view illustrating a state in which a covering member is arranged in a method for manufacturing a light emitting device according to a second embodiment. FIG. 7 is a cross-sectional view illustrating a state in which the light emitting device is separated into pieces in the method for manufacturing the light emitting device according to the second embodiment. FIG. 7 is a cross-sectional view schematically illustrating a light emitting device in which a wiring board including a metal block according to a modified example is used and a light source is disposed on the upper surface of the metal block. 13 is a cross-sectional view illustrating an outline of a light emitting device in which a light source is disposed on the lower surface of a metal block using a wiring board including a metal block according to a modified example. FIG. 7 is a perspective view schematically illustrating a metal block according to a modification.

Embodiments according to the present disclosure will be described below with reference to the drawings. However, the embodiments described below are for embodying the technical idea of the present disclosure, and unless there is a specific description, the invention is not limited to the following. What is described in one embodiment is applicable to other embodiments and modifications. In addition, the drawings schematically show the embodiments, and in order to clarify the explanation, the scale, spacing, positional relationship, etc. of each member may be exaggerated, or illustration of some members may be omitted. There is. The directions shown in each figure indicate relative positions between components and are not intended to indicate absolute positions. Note that the same names and symbols basically indicate the same or homogeneous members, and detailed explanations will be omitted as appropriate. Furthermore, in the embodiments, "covering" is not limited to the case of direct contact, but also includes the case of covering indirectly, for example, via another member.

[Wiring board]
A wiring board 1 according to an embodiment will be described with reference to FIGS. 1A and 1B. FIG. 1A is a plan view schematically illustrating the wiring board 1. FIG. FIG. 1B is a cross-sectional view taken along line IB-IB in FIG. 1A. FIG. 1C is a perspective view schematically illustrating a metal block according to an embodiment.

The wiring board 1 has an upper surface 15A, a lower surface 15B on the opposite side of the upper surface 15A, and a side surface 15C continuous with the upper surface 15A and the lower surface 15B. and a side surface 15C of the metal block 15 facing the light reflective member 40, and an inorganic light reflective member 40 arranged on the side surface 15C of the metal block 15 and forming a flat plate shape together with the metal block 15. A metal oxide layer 16 is disposed thereon. Each structure of the wiring board 1 will be explained below.

(metal block)
The metal block 15 is a member that becomes a wiring material in the wiring board 1. The metal block 15 has an upper surface 15A, a lower surface 15B opposite to the upper surface 15A, and a side surface 15C continuous to the upper surface 15A and the lower surface 15B. Here, the metal block 15 has a rectangular parallelepiped shape, as an example, and the upper surface 15A, the lower surface 15B, and the four side surfaces 15C are all rectangular.

It is preferable that the maximum diameter of the upper surface 15A and the lower surface 15B of the metal block 15 is 100 μm or more and 800 μm or less, and the thickness is 100 μm or more and 500 μm or less. Note that the maximum diameter of the upper surface 15A and the lower surface 15B of the rectangular parallelepiped metal block 15 is the length of the diagonal of each of the upper surface 15A and the lower surface 15B.

A plurality of metal blocks 15 are arranged in rows and columns in plan view and are spaced apart from each other. The upper surfaces 15A of the metal blocks 15 are parallel to each other and are arranged so as to be in contact with one plane. The lower surfaces 15B of the metal block 15 are parallel to each other and are arranged so as to be in contact with a plane different from the plane with which the upper surface 15A is in contact. The distance between adjacent metal blocks 15 is preferably 100 μm or more and 300 μm or less. The smaller the distance between adjacent metal blocks 15, the smaller the thermal resistance of wiring board 1 can be.

The base material of the metal block 15 is metal. A metal oxide layer 16 is arranged on the side surface 15C of the metal block 15. The thickness of the metal oxide layer 16 is preferably 0.1 μm or more and 10 μm or less. By disposing the metal oxide layer 16, the bonding with the light reflective member 40 disposed on the side surface 15C of the metal block 15 can be strengthened. If the metal oxide layer 16 is thinner than 0.1 μm, the bond will not be strong, and even if it is thicker than 10 μm, the effect of further improving the bond strength will be small.

As the base material of the metal block 15, at least one selected from copper, silver, gold, aluminum, or an alloy containing these may be used, and copper is preferable. For the metal oxide layer 16, at least one selected from copper oxide, silver oxide, gold oxide, aluminum oxide, or oxides containing these may be used, but a copper oxide layer is preferable. By using copper as the base material of the metal block 15, electrical and thermal conductivity can be improved.

(light reflective member)
The light reflective member 40 is a member that is disposed between the metal blocks 15 and insulates and supports the metal blocks 15 from each other. The light reflective member 40 is arranged to cover the side surface 15C of the metal block 15, and the upper surface 15A and the lower surface 15B are exposed from the light reflective member 40. The light reflective member 40 faces the side surface 15C with the metal oxide layer 16 in between.
The wiring board 1 is formed into a flat plate shape by a light reflective member 40 and a metal block 15. The upper surface of the light reflective member 40 forms the upper surface of the wiring board 1 together with the upper surface 15A of the metal block 15. The lower surface of the light reflective member 40 constitutes the lower surface of the wiring board 1 together with the lower surface 15B of the metal block 15.

The light reflective member 40 has light reflective properties. The light reflective member 40 can be made of white ceramics, for example. By making the light reflective member 40 white, the light reflectivity can be improved, and by using ceramics, the heat resistance can be improved.
The light reflective member 40 contains at least one of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or a mixture of one or more of these. It is preferable to include. In addition to the above-mentioned boron nitride, silicon nitride, aluminum nitride, etc., the light reflective member may further include silica and an alkali metal.

The wiring board 1 uses a metal block 15, which is a block-shaped metal having an upper surface 15A, a lower surface 15B, and a side surface 15C, as a wiring material, so that there is no need to route the wiring, the wiring resistance is reduced, and the structure is thermally conductive. It is possible to improve heat dissipation.
By providing the metal oxide layer 16 on the surface of the metal block 15, the wiring board 1 can improve its adhesion to ceramics. Furthermore, by supporting the side surface 15C of the metal block 15, heat dissipation is further improved, and by using the inorganic light reflective member 40 as the member supporting the side surface 15C, the substrate has excellent light reflectivity and high heat resistance. can do.

[Method for manufacturing wiring board]
Next, a wiring board manufacturing method S10 according to the embodiment will be described with reference to FIGS. 2 to 3H. FIG. 2 is a flowchart illustrating the wiring board manufacturing method S10. FIG. 3A is a cross-sectional view illustrating a flat plate 11 that is the material of the metal plate 10 to be prepared. FIG. 3B is a cross-sectional view illustrating a state in which a mask 81 is formed on the flat plate 11. FIG. 3C is a cross-sectional view illustrating a state in which the convex portion 14 is formed by etching. FIG. 3D is a cross-sectional view illustrating the prepared metal plate 10. FIG. 3E is a cross-sectional view illustrating a state in which the metal oxide layer 16 is formed on the metal plate 10. FIG. 3F is a cross-sectional view illustrating a state in which the light reflective member 40 is formed on the metal plate 10. FIG. 3G is a cross-sectional view illustrating a state in which a part of the light reflective member 40 is removed to expose the base metal of the metal plate 10. FIG. 3H is a cross-sectional view illustrating a state in which a part of the metal plate 10 is removed to expose the light reflective member 40 between adjacent metal blocks 15.

The wiring board manufacturing method S10 includes preparing a metal plate 10 having a first surface 10A having a plurality of convex portions 14 spaced apart from each other and a second surface 10B opposite to the first surface 10A; Forming a metal oxide layer 16 on the first surface 10A of the metal plate 10 S12, and disposing an uncured inorganic light reflective member 41 on the first surface 10A of the metal plate 10 on which the metal oxide layer 16 is formed. S13, curing the disposed light reflective member 41 S14, removing a portion of the cured light reflective member 40 S15, and removing a portion of the light reflective member 40 to form a convex surface. exposing the base metal of the metal plate 10 on the upper surface of the portion 14; removing a part of the second surface 10B of the metal plate 10; S17; and removing a portion of the second surface 10B of the metal plate 10. exposing the light reflective member 40 between adjacent metal blocks 15 by removing the portion S18. Hereinafter, a case where the base material of the metal block 15 is copper will be described as an example. Note that unless otherwise specified, the first surface 10A refers not only to the upper surface in a flat shape but also to the entire surface on one side. In other words, when the first surface 10A has a concave shape, it includes not only the inner surface of the concave shape but also the outer surface and the inner surface. Further, when the first surface 10A has a convex shape, it includes not only the convex upper plane but also the lower plane and side surfaces.

(Prepare a metal plate)
Preparing a metal plate In step S11, a metal plate 10 having a plurality of convex portions 14 spaced apart from each other is prepared. The metal plate 10 has a first surface 10A and a second surface 10B opposite to the first surface 10A, and the convex portion 14 is formed on the first surface 10A.
First, a copper flat plate 11 that is the material of the metal plate 10 is prepared. The thickness of the flat plate 11 is not particularly limited, but is preferably 300 μm or more and 1000 μm or less, particularly preferably 400 μm or more and 700 μm or less. The thickness of this flat plate 11 can be set to include the convex portion 14 of the metal plate 10. By forming the mask 81 in the region of the flat plate 11 where the convex portion 14 is to be formed and performing etching, the region where the mask 81 is formed remains, and the convex portion 14 can be formed. Then, the mask 81 is removed and the metal plate 10 is prepared.

Etching can be performed, for example, so that the height H1 of the convex portion 14 is greater than or equal to 105 μm and less than or equal to 600 μm. The height H1 of the convex portion 14 is preferably 150 μm or more and 300 μm or less. The height H1 of the convex portion 14 is the height from the top surface of the metal plate 10 on which the convex portion 14 is not formed to the top surface of the convex portion 14.

(forms a metal oxide layer)
Forming a metal oxide layer S12 forms a metal oxide layer 16 on the metal plate 10 . Here, the metal oxide layer 16 is a copper oxide layer. The metal oxide layer 16 only needs to be formed on the first surface 10A. Here, the metal oxide layer 16 is formed on the first surface 10A and the second surface 10B.

First, the surface on which the metal oxide layer 16 is to be formed, that is, at least the first surface 10A of the metal plate 10, is subjected to an alkali treatment. Here, the first surface 10A and the second surface 10B are subjected to alkali treatment.

In the alkali treatment, the metal plate 10 is immersed in a sodium hydroxide or potassium hydroxide aqueous solution having a weight percentage of 3% or more and 10% or less for 5 minutes or more and 10 minutes or less, and then at 100°C or more and 200°C or less for 5 or more minutes and 10 minutes or less. This can be done by heating. The concentration of the sodium hydroxide or potassium hydroxide aqueous solution is preferably 5% or more and 10% or less, and the immersion time is preferably 7 minutes or more and 10 minutes or less. Further, the heating temperature is preferably 125° C. or more and 200° C. or less, and the heating time is preferably 7 minutes or more and 10 minutes or less.

The metal oxide layer 16 is formed to have a thickness of 0.1 μm or more and 10 μm or less. The thickness of the metal oxide layer 16 is preferably 0.5 μm or more and 8 μm or less, more preferably 1 μm or more and 5 μm or less.
Note that when potassium hydroxide or sodium hydroxide is included in the components of the uncured light-reflecting member 41 to be described later, the alkali treatment and heat treatment can be omitted.

(Place uncured light reflective material)
Arranging an uncured light-reflective member In S13, an uncured light-reflective member 41 is arranged on the first surface 10A of the metal plate 10 on which the metal oxide layer 16 is formed. The uncured light reflective member 41 is arranged so as to cover at least the side surface of the convex portion 14 . Here, the light reflective member 41 is arranged so as to cover the side and top surfaces of the convex portion 14. The uncured light-reflecting member 41 has fluidity and can be placed, for example, by potting, spraying, inkjet, printing, or the like.

The uncured light reflective member 41 is an inorganic material having fluidity, and is made of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or one of these. It is preferable that at least one of the above mixtures is included.

The uncured light reflective member 41 can be made of a type of ceramic that hardens at low temperatures. The low temperature is, for example, 70°C or higher and 500°C or lower. Internal stress can be reduced by using ceramics that harden at low temperatures.
The uncured light reflective member 41 can contain either sodium metasilicate or aluminum phosphate as a curing agent. Note that the uncured light-reflecting member 41 may contain an organic solvent or the like, and the light-reflecting member 40 of an inorganic material may be formed after curing.

(Cure the light reflective member)
Curing the light reflective member In S14, the disposed uncured light reflective member 41 is cured. The light reflective member 41 can be cured by heating while applying pressure. As an example, a case where main curing is performed after temporary curing will be described. The temperature for temporary curing can be 50°C or more and 200°C or less, and the temperature for main curing can be 200°C or more and 500°C or less. The temperature for temporary curing is preferably 70°C or more and 150°C or less, and the temperature for main curing is preferably 250°C or more and 300°C or less.

The pressure for temporary curing and main curing can be 0.5 MPa or more and 3 MPa or less, preferably 1 MPa or more and 2 MPa or less. The pressure may be changed between temporary curing and main curing. The time for applying pressure and heating can be, for example, 30 minutes or more and 60 minutes or less for each of temporary curing and main curing.

(Remove part of the light reflective material)
Removing a Part of the Light Reflective Member In S15, the light reflective member 40 formed on the upper surface of the convex portion 14 is removed. Removing a portion of the light reflective member S15 includes exposing the metal of the base material of the metal plate S16. Exposure of the base metal of the metal plate In step S16, the metal oxide layer 16 on the top surface of the convex portion 14 is removed to expose the base metal of the metal plate 10 on the top surface of the convex portion 14.
Removal of a portion of the light reflective member 40 and removal of the metal oxide layer 16 can be performed, for example, by polishing or grinding using a processing device that uses abrasive grains. In addition to polishing or grinding, cutting or blasting may be used in combination.

(Remove part of the second side of the metal plate)
Removing a part of the second surface side of the metal plate S17 removes a part of the metal plate 10 from the second surface 10B side of the metal plate 10 to separate the protrusions 14, and the separated protrusions 14 becomes the metal block 15. That is, the metal plate 10 can be polished or ground from the second surface 10B side of the metal plate 10 to make it thinner, or the metal plate 10 can be cut in a direction parallel to the thickness direction. The metal plate 10 is thinned until the light reflecting member between adjacent convex portions 14 is exposed from the second surface side. It is preferable to remove the metal plate 10 so that the thickness of the metal plate 10 does not vary depending on the location. Note that if the metal oxide layer 16 is formed on the second surface 10B of the metal plate 10, the metal oxide layer 16 can also be removed.
The metal plate 10 and the metal oxide layer 16 can be removed by, for example, polishing or grinding using a processing device that uses abrasive grains, similar to removing a part of the light reflective member S15. Cutting and blasting may also be used together.

In step S17 of removing a portion of the second surface of the metal plate, the thickness of the metal block 15 can be adjusted by adjusting the amount of the metal plate 10 to be removed. The thickness of the metal block 15 can be 100 μm or more and 500 μm or less. The thickness of the metal block 15 is preferably 150 μm or more and 250 μm or less.

(Exposing the light reflective member)
Removing a part of the second surface side of the metal plate S17 includes exposing the light reflective member S18. In exposing the light reflective member S18, the light reflective member 40 is exposed between the metal blocks 15. By exposing the light reflective member 40, the wiring board 1 is provided with the metal blocks 15 that are spaced apart from each other.

In the wiring board manufacturing method S10, an uncured inorganic light-reflecting member 41 is placed on the first surface 10A of the metal plate 10 on which the convex portions 14 and the metal oxide layer 16 are formed, and is cured. By removing a part of the light reflective member 40 and a part of the second surface 10B side of the metal plate 10, the metal base material is exposed on the upper surface 15A and the lower surface 15B, and the metal base material is exposed on the side surface 15C with the metal oxide layer 16 interposed therebetween. It is possible to manufacture the wiring board 1 including the metal blocks 15 on which the light reflective member 40 is arranged and which are supported by the light reflective member 40 and spaced apart from each other.

(Modified example of wiring board manufacturing method)
Next, a modification of the wiring board manufacturing method will be described with reference to FIGS. 4A to 4E. FIG. 4A is a cross-sectional view illustrating a flat plate 12 that is the material of the metal plate 10 to be prepared. FIG. 4B is a cross-sectional view illustrating a state in which the dry film 85 is placed on the flat plate 12. FIG. 4C is a cross-sectional view illustrating a state in which the mask 82 is formed on the flat plate 12. FIG. 4D is a cross-sectional view illustrating a state in which the convex portion 14 is formed by plating. FIG. 4E is a cross-sectional view illustrating the prepared metal plate 10.

The modification of the wiring board manufacturing method differs from manufacturing method S10 in preparing a metal plate, and is common to manufacturing method S10 in other respects. In preparing the metal plate according to the modification, a metal plate 10P having a plurality of convex portions 14P spaced apart from each other is prepared by a method different from preparing the metal plate S11 in the manufacturing method S10.
First, a copper flat plate 12, which is the material of the metal plate 10P, is prepared. The thickness of this flat plate 12 can be set to a thickness that does not include the convex portions 14 of the metal plate 10 prepared in manufacturing method S10.

A dry film 85 is placed on the surface of the flat plate 12 on which the convex portion 14P is to be formed. The dry film 85 is then exposed and developed to form a mask 82 in the area where the convex portion 14P is not to be formed. Then, metal plating is performed on the surface of the flat plate 12 on which the mask 82 is formed to form the convex portion 14P. The metal plating can be copper plating. The metal plating can be performed so that the convex portion 14P has the same height as the height H1 in the manufacturing method S10. Then, the mask 82 is removed to prepare the metal plate 10P. After forming the metal oxide layer S12, the manufacturing method S10 can be carried out using the prepared metal plate 10P.

[Light-emitting device (first embodiment)]
Next, the light emitting device 100 according to the first embodiment will be described with reference to FIGS. 5A to 6C. FIG. 5A is a plan view schematically illustrating the light emitting device according to the first embodiment. FIG. 5B is a cross-sectional view taken along the line VB-VB in FIG. 5A. FIG. 6A is a plan view schematically illustrating a light source of a light emitting device according to an embodiment. FIG. 6B is a bottom view schematically illustrating the light source of the light emitting device according to the embodiment. FIG. 6C is a cross-sectional view taken along the line VIC-VIC in FIG. 6A.

The light emitting device 100 includes the wiring board 1 according to the embodiment, and a light source 20 including a light emitting element 22 disposed on the upper surface of the wiring board 1 and having a pair of element electrodes 21, each of the pair of element electrodes 21 having a , are connected to each of the adjacent metal blocks 15 via a conductive member 50. Here, a plurality of light sources 20 are arranged.
The light emitting device 100 is, for example, a module type light emitting device in which a plurality of light sources 20 are arranged on the wiring board 1. Each configuration of the light emitting device 100 will be described below. Note that the upper surface of the wiring board 1 is a surface where the upper surface 15A of the metal block 15 is exposed.

(wiring board)
The wiring board 1 has metal blocks 15 formed and arranged in accordance with the size and arrangement of the light sources 20 in the light emitting device 100, the spacing between the pair of element electrodes 21, and the like. Here, the wiring board 1 has a plating layer 17 on the upper surface 15A of the metal block 15. The plating layer 17 is formed on the entire upper surface 15A of the metal block 15. It is preferable that the plating layer 17 is, for example, nickel-gold plating in which a nickel plating layer and a gold plating layer are laminated in this order on the upper surface 15A of the metal block 15 made of copper. By having the plating layer 17, it is possible to improve the electrical and thermal connection between the element electrode 21 of the light emitting element 22 and the metal block 15.

(light source)
The light source 20 is a member that includes at least a light emitting element 22 having a pair of element electrodes 21. Here, the light source 20 includes a light emitting element 22, a translucent member 30 disposed on the light extraction surface side of the light emitting element 22, and a resin member 25 that covers the side surfaces of the light emitting element 22 and the translucent member 30. It is an integrally formed member. The resin member 25 may further cover the lower surface of the light emitting element 22 except for the element electrode 21.
Light source 20 may further include other members. Further, the light source 20 may be only the light emitting element 22. When the light source 20 is made up of only the light emitting element 22, it can be combined with a transparent member 30 that is separate from the light source 20, for example.

(Light emitting element)
The light-emitting element 22 includes a semiconductor stack, in which a transparent substrate made of sapphire, gallium nitride, or the like is disposed on the top surface of the semiconductor stack, and has a pair of device electrodes 21 on the bottom surface. Any composition can be used as the semiconductor stack depending on the desired emission wavelength, but for example, nitride semiconductors (In _x Al _y Ga _1-x-y N, which can emit blue or green light) are used. 0≦X, 0≦Y, X+Y≦1), GaP, or GaAlAs or AlInGaP, which can emit red light, can be used. Further, the size and shape of the light emitting element 22 can be appropriately selected depending on the purpose of use.

(Element electrode)
The pair of element electrodes 21 have a rectangular shape, for example, and are exposed on the lower surface of the light source 20. Each of the pair of element electrodes 21 is connected to each adjacent metal block 15 via a conductive member 50. Further, here, adjacent metal blocks 15 are connected to the element electrodes 21 of the same light source 20 or to the element electrodes 21 of adjacent light sources 20.
The element electrode 21 can be formed of a single layer or a laminated film of metals such as gold, platinum, palladium, rhodium, nickel, tungsten, molybdenum, chromium, and titanium, or alloys thereof. The conductive member 50 can be made of, for example, gold-tin solder, copper-tin solder, or the like. Note that here, a plating layer 17 is arranged on the upper surface 15A of the metal block 15, and the element electrode 21 is connected to the metal block 15 via the conductive member 50 and the plating layer 17. The plating layer 17 may be nickel-gold plating without providing the conductive member 50, and the element electrode 21 and the plating layer 17 may be ultrasonically bonded.

The light emitting device 100 can reduce wiring resistance and improve heat dissipation by mounting the light source 20 on the wiring board 1 having the metal block 15 which is a block-shaped wiring material. Furthermore, since each of the pair of element electrodes 21 is connected to each of the adjacent metal blocks 15, and a highly reflective member 40 with high light reflectivity can be placed directly under the light source 20, light extraction efficiency is improved. can be achieved.

(Translucent member)
The translucent member 30 is made of, for example, a translucent resin material, and can be made of epoxy resin, silicone resin, or a mixture of these resins. The translucent member 30 may contain a phosphor, for example, by including a phosphor that absorbs blue light from the light emitting element 22 and emits yellow light, it emits white light from the light source 20. It can be emitted. Further, the translucent member 30 may contain multiple types of phosphors, for example, a phosphor that absorbs blue light from the light emitting element 22 and emits green light, and a phosphor that emits red light. White light can also be emitted from the light source 20 by including a phosphor that emits light.

The translucent member 30 may further contain a luminescent material such as a phosphor or a quantum dot. Such phosphors include, for example, yttrium aluminum (gallium doped) garnet activated with cerium, nitrogen-containing calcium aluminosilicate (strontium) activated with europium, potassium fluorosilicate activated with manganese, β Examples include sialon-based phosphors. Specifically, the phosphors include yttrium-aluminum-garnet-based phosphors (e.g., (Y,Gd) ₃ (Al, Ga) ₅ O ₁₂ :Ce), lutetium-aluminum-garnet-based phosphors (e.g., Lu ₃ (Al, Ga) ₅ O ₁₂ :Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb ₃ (Al, Ga) ₅ O ₁₂ :Ce), CCA-based phosphor (e.g., Ca ₁₀ (PO ₄ )) ₆ Cl ₂ :Eu), SAE phosphor (e.g. Sr ₄ Al ₁₄ O ₂₅ :Eu), chlorosilicate phosphor (e.g. Ca ₈ MgSi ₄ O ₁₆ Cl ₂ :Eu), silicate phosphor (e.g. , (Ba, Sr, Ca, Mg) ₂ SiO ₄ :Eu), β-sialon-based phosphor (e.g., (Si, Al) ₃ (O,N) ₄ :Eu) or α-sialon-based phosphor (e.g., Ca Oxynitride-based phosphors such as (Si,Al) ₁₂ (O,N) ₁₆ :Eu), LSN-based phosphors (e.g. (La,Y) ₃ Si ₆ N ₁₁ :Ce), BSESN-based phosphors ( For example, (Ba,Sr) ₂ Si ₅ N ₈ :Eu), SLA-based phosphor (e.g., SrLiAl ₃ N ₄ :Eu), CASN-based phosphor (e.g., CaAlSiN ₃ :Eu), or SCASN-based phosphor (e.g. , (Sr,Ca)AlSiN ₃ :Eu), KSF-based phosphors (e.g., K ₂ SiF ₆ :Mn), KSAF-based phosphors (e.g., K ₂ (Si _1-x Al _x )F _6-x :Mn, where x satisfies 0<x<1) or fluoride-based phosphor such as MGF-based phosphor (for example, 3.5MgO・0.5MgF ₂・GeO ₂ :Mn) Examples include phosphors and the like. Quantum dots include quantum dots having a perovskite structure (for example, (Cs, FA, MA) (Pb, Sn) (F, Cl, Br, I) ₃ , where FA is formamidinium and MA is methyl. represents ammonium), II-VI group quantum dots (e.g. CdSe), III-V group quantum dots (e.g. InP), quantum dots with chalcopyrite structure (e.g. (Ag, Cu) (In, Ga) (S,Se) ₂ ) and the like.

(Resin member)
The resin member 25 is a member that covers the light emitting element 22 and protects the light emitting element 22. The resin member 25 may have a light reflective property, a light transmitting property, or a light absorbing property. It is preferable that the resin member 25 has light reflective properties. The light-reflecting resin member 25 can be formed, for example, by incorporating a light-reflecting substance into the same resin material as the light-transmitting member 30. Examples of the light-reflective substance include titanium oxide, silicon oxide, zirconium oxide, magnesium oxide, yttrium oxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, and the like. Moreover, when the resin member 25 has translucency, it may contain a wavelength conversion member such as a fluorescent substance.

[Method for manufacturing light emitting device according to first embodiment]
Next, a method S20 for manufacturing the light emitting device 100 will be described with reference to FIGS. 7 to 8C. FIG. 7 is a flowchart illustrating a method S20 for manufacturing a light emitting device. FIG. 8A is a cross-sectional view illustrating the prepared metal plate 10. FIG. 8B is a cross-sectional view illustrating a state in which the plating layer 17 is formed on the surface of the metal block 15. FIG. 8C is a cross-sectional view illustrating a state in which the light source 20 is placed on the wiring board 1.

The manufacturing method S20 of a light emitting device includes preparing the wiring board 1 according to the embodiment S21, arranging a plurality of light sources 20 including a light emitting element 22 having a pair of element electrodes 21 on the wiring board 1, S23. including. In arranging the light source S23, each of the pair of element electrodes 21 is connected to each of the adjacent metal blocks 15 via the conductive member 50. Here, a case will be described in which step S22 of forming the plating layer 17 on the surface of the metal block 15 is performed before step S23 of arranging the light source. Note that a case will be described in which the surface where the upper surface 15A of the metal block 15 is exposed is the upper surface of the wiring board 1, and the light source 20 is disposed on the upper surface of the wiring board 1.

(Prepare the wiring board)
Preparing a Wiring Board In step S21, a wiring board 1 on which metal blocks 15 are formed in accordance with the size and arrangement of the light sources 20 in the light emitting device 100, the spacing between the pair of element electrodes 21, etc. is prepared. It is preferable that no metal block 15 that is not connected to the light sources 20 is placed between adjacent light sources 20 .

(Forming a plating layer)
In preparing a plating layer S22, a plating layer 17 is formed on the upper surface 15A of the metal block 15. The plating layer 17 can be formed by forming a nickel plating base on the upper surface 15A of the metal block 15, which is made of copper, for example, and then plating the base with gold.

(Place the light source)
In arranging the light source S23, the light source 20 is arranged on the wiring board 1. Each of the pair of element electrodes 21 is connected to each of the adjacent metal blocks 15 via a conductive member 50. Here, a plating layer 17 is formed on the upper surface 15A of the metal block 15. Therefore, the element electrode 21 is connected to the metal block 15 via the conductive member 50 and the plating layer 17.

[Light-emitting device according to second embodiment]
Next, light emitting devices 200 and 300 according to a second embodiment will be described with reference to FIGS. 9A to 9C. FIG. 9A is a plan view schematically illustrating the light emitting device 200. FIG. 9B is a cross-sectional view taken along line IXB-IXB in FIG. 9A. FIG. 9C is a cross-sectional view schematically illustrating the light emitting device 300 that has been separated into pieces.

Like the light emitting device 100, the light emitting device 200 is a module type light emitting device in which a plurality of light sources are arranged on the wiring board 1. The light emitting device 300 is obtained by cutting the light emitting device 200 into pieces along cutting lines L1 and L2, and is a chip scale package (CSP) type light emitting device including one light source.
The light emitting device 200 includes a light emitting element 22 and a translucent member 30 in place of the light source 20 of the light emitting device 100, and further includes a covering member 60. In other respects, the light emitting device 200 is the same as the light emitting device 100. The light emitting device 300 is obtained by dividing the light emitting device 200 into individual pieces, and has the same configuration as the light emitting device 200. Each configuration of the light emitting device 200 will be described below. Note that, like the light emitting device 100, the upper surface of the wiring board 1 is a surface where the upper surface 15A of the metal block 15 is exposed.

(light source)
The light source of the light emitting device 200 is composed of only the light emitting element 22. A translucent member 30 is arranged on the upper surface of the light emitting element 22. The translucent member 30 can be similar to the light source 20 of the light emitting device 100.

(Coated member)
The covering member 60 is disposed on the upper surface of the wiring board 1, and is a member that covers and protects the upper and lower surfaces of the light emitting element 22 and the side surfaces of the translucent member 30. The upper surface of the transparent member 30 is exposed from the covering member 60. The covering member 60 also covers the side surfaces of the element electrode 21 and the conductive member 50 by entering between the light emitting element 22 and the wiring board 1 .
The covering member 60 can be formed of a resin having light-reflecting properties, light-transmitting properties, light-blocking properties, etc., a resin containing a light-reflecting substance in these resins, or the like. It is preferable that the covering member 60 has at least one of light reflecting properties and light blocking properties. Examples of the resin include resins or hybrid resins containing one or more of silicone resins, modified silicone resins, epoxy resins, modified epoxy resins, and acrylic resins. Examples of the light-reflective substance include titanium oxide, silicon oxide, zirconium oxide, potassium titanate, alumina, aluminum nitride, boron nitride, and mullite. The covering member 60 may contain a phosphor, a diffusing material, a coloring agent, and the like.

Like the light emitting device 100, the light emitting device 200 can reduce wiring resistance and improve heat dissipation and light extraction efficiency. In addition, by providing the covering member 60 on the upper surface of the wiring board 1, the light emitting device 200 can protect the upper surface of the wiring board 1 and the electrical connection members, thereby improving reliability.

Note that the light emitting device 300 is cut along cutting lines L1 and L2 passing through the middle of adjacent metal blocks 15 in the light emitting device 200 so as not to cut the metal blocks 15. The side surface of the light emitting device 300 is composed of a covering member 60 and a light reflective member 40 of the wiring board 1.

[Method for manufacturing light emitting device according to second embodiment]
Next, a method S30 for manufacturing the light emitting devices 200, 300 according to the second embodiment will be described with reference to FIGS. 10 to 11D. FIG. 10 is a flowchart illustrating a method for manufacturing the light emitting devices 200, 300. FIG. 11A is a cross-sectional view illustrating a state in which the light emitting element 22 is arranged. FIG. 11B is a cross-sectional view illustrating a state in which the translucent member 30 is arranged. FIG. 11C is a cross-sectional view illustrating a state in which the covering member 60 is arranged. FIG. 11D is a cross-sectional view illustrating a state in which it is separated into pieces.

The light emitting device manufacturing method S30 includes preparing the wiring board 1 according to the embodiment S31 and arranging a plurality of light sources including a light emitting element 22 having a pair of element electrodes 21 on the wiring board 1 S33. include. In arranging the light source S33, each of the pair of element electrodes 21 is connected to each of the adjacent metal blocks 15 via the conductive member 50. After arranging the light source S33, arranging the translucent member 30 S34 and arranging the covering member 60 S35 may be included, and may further include singulating S36.
Here, similarly to the light emitting device manufacturing method S20, forming the plating layer 17 on the surface of the metal block 15 is performed in S32 before arranging the light source in S33. Moreover, preparing a wiring board S31 and forming a plating layer S32 are common to the light emitting device manufacturing method S20. Note that a case will be described in which the surface where the upper surface 15A of the metal block 15 is exposed is the upper surface of the wiring board 1, and the light source is arranged on the upper surface of the wiring board 1.

(Place the light source)
Arranging the light source S33 can be performed in the same manner as arranging the light source S23 in the light emitting device manufacturing method S20. However, the light source used here is composed of only the light emitting element 22, and the light emitting element 22 is arranged on the wiring board 1 on which the plating layer 17 is formed.

(Placing the light-transmitting member)
In disposing the light-transmitting member S34, the light-transmitting member 30 is disposed on the upper surface of the light-emitting element 22. The light-transmitting member 30 can be disposed by applying the material of the uncured light-transmitting member 30 by, for example, potting, spraying, inkjet printing, printing, or the like, and then curing the material. The light-transmitting member 30 may be a member formed in a sheet or plate shape and disposed on the upper surface of the light-emitting element 22 via an adhesive.

(Place the covering member)
In step S<b>35 of disposing the covering member, the covering member 60 is arranged on the upper surface of the wiring board 1 so that the upper surface of the transparent member 30 is exposed. It is preferable that the covering member 60 is disposed so as to cover the side surfaces of the light emitting element 22 and the translucent member 30, and is also disposed so as to cover the lower surface of the light emitting element 22 and the conductive member 50. The coating member 60 is coated by, for example, disposing a nozzle of a resin discharging device above the wiring board 1, discharging an uncured resin material from the tip of the nozzle, moving the nozzle, and then curing the material. can be placed. It is preferable to apply the coating member 60 in multiple times. The upper surface of the covering member 60 is preferably flush with the upper surfaces of the adjacent light emitting elements 22. However, since the covering member 60 is arranged between adjacent light emitting elements 22, the covering member 60 may be arranged so that a part of the upper surface thereof is sunken or raised. Further, by polishing or grinding the raised covering member 60, the upper surface of the covering member 60 can be made flush with the upper surface of the adjacent light emitting element 22. Note that not only the covering member 60 but also the upper surface of the light emitting element 22 may be polished or ground.

(Individualize)
In the step of dividing into individual pieces (S36), the chip is divided into individual pieces each including one light emitting element 22. The division into individual pieces can be performed by cutting with a dicing blade, laser irradiation, breaking, or the like, for example.
In the light emitting device manufacturing method S30, the light emitting device 200 can be manufactured if singulation is not performed, and the light emitting device 300 can be manufactured if singulation is performed.

(Modified example of metal block)
Next, a metal block 18 according to a modification will be described with reference to FIGS. 12A to 12C. FIG. 12A is a cross-sectional view schematically illustrating a light emitting device in which a wiring board including a metal block 18 according to a modification is used and a light source 20 is disposed on an upper surface 18A of the metal block 18. FIG. 12B is a cross-sectional view schematically illustrating a light emitting device in which a wiring board including a metal block 18 according to a modification is used and a light source 20 is disposed on a lower surface 18B of the metal block 18. FIG. 12C is a perspective view schematically illustrating a metal block 18 according to a modification.

In the wiring board manufacturing method S10, it has been described that the protrusions 14 formed by etching are separated to form metal blocks. Depending on the etching conditions, an undercut may become large at the edge of the mask 81 as the etching progresses along the lower surface of the mask 81. Due to the undercut, the convex portion 14 is formed into a shape that becomes narrower on the tip side, and a metal block 18 can be formed in which the upper surface 18A is smaller than the lower surface 18B.
The outer shape of the metal block 18 is a truncated quadrangular pyramid, and the side surface 18C is curved convexly inward. The upper surface 18A and the lower surface 18B are rectangular, and the upper surface 18A is smaller than the lower surface 18B. When the light source 20 is disposed on the wiring board including the metal block 18, the light source 20 can be disposed on either the upper surface 18A side or the lower surface 18B side. However, it is preferable that the light source 20 is placed on the upper surface 18A side. By arranging the light source 20 on the upper surface 18A side, the area of the light reflective member 40 directly under the light source 20 becomes larger than when the light source 20 is arranged on the lower surface 18B side, which is advantageous from the viewpoint of light reflection. To become.

Note that the metal block is not limited to the shape of a rectangular parallelepiped or a truncated quadrangular pyramid, but may have various shapes such as a cylinder, an elliptical cylinder, a triangular or polygonal prism, a truncated cone, or a truncated pyramid. Furthermore, the metal blocks can be formed into various shapes depending on the shapes of the masks 81 and 82, etching conditions, and the like.

The present disclosure includes embodiments of the following sections.
(Section 1)
preparing a metal plate having a first surface having a plurality of convex portions spaced apart from each other and a second surface opposite to the first surface;
forming a metal oxide layer on the first surface of the metal plate;
disposing an uncured inorganic light-reflecting member on the first surface of the metal plate on which the metal oxide layer is formed;
Curing the disposed light reflective member;
removing a portion of the cured light reflective member;
exposing the base metal of the metal plate on the upper surface of the convex portion by removing a part of the light reflective member;
removing a part of the second surface side of the metal plate;
A method for manufacturing a wiring board, comprising: exposing the light reflective member between adjacent metal blocks by removing a portion of the second surface of the metal plate.
(Section 2)
2. The method of manufacturing a wiring board according to item 1, wherein in preparing the metal plate, the convex portion is formed by placing a mask on the metal plate and etching it.
(Section 3)
2. The method of manufacturing a wiring board according to item 1, wherein, in preparing the metal plate, the convex portion is formed by placing a dry film on the metal plate and performing metal plating.
(Section 4)
In preparing the metal plate, the wiring board according to any one of Items 1 to 3, wherein the protrusions are arranged in row and column directions, and the upper surface of the protrusions is rectangular in plan view. Production method.
(Section 5)
5. The method for manufacturing a wiring board according to any one of Items 1 to 4, wherein in preparing the metal plate, the distance between the adjacent convex portions is 100 μm or more and 300 μm or less.
(Section 6)
6. The method for manufacturing a wiring board according to any one of Items 1 to 5, wherein in preparing the metal plate, the base material of the metal plate is copper.
(Section 7)
7. The method for manufacturing a wiring board according to any one of Items 3 to 6, wherein in preparing the metal plate, the metal plating is copper plating.
(Section 8)
In arranging the light reflective member, the light reflective member is made of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or one of these. 8. The method for manufacturing a wiring board according to any one of Items 1 to 7, which includes at least one kind of a mixture of at least one species.
(Section 9)
9. The method for manufacturing a wiring board according to any one of Items 1 to 8, wherein in arranging the light reflective member, the light reflective member is placed so as to cover at least a side surface of the convex portion.
(Section 10)
Manufacturing the wiring board according to any one of Items 1 to 9, wherein in arranging the light reflective member, the light reflective member contains either sodium metasilicate or aluminum phosphate as a curing agent. Method.
(Section 11)
Manufacturing the wiring board according to any one of Items 1 to 10, wherein in curing the light reflective member, temporary curing is performed at 50°C or more and 200°C or less, and then main curing is performed at 200°C or more and 500°C or less. Method.
(Section 12)
Item 12. The method for manufacturing a wiring board according to item 11, wherein in curing the light reflective member, the temporary curing and the main curing are performed at a pressure of 0.5 MPa or more and 3 MPa or less.
(Section 13)
13. The method for manufacturing a wiring board according to any one of Items 1 to 12, wherein in forming the metal oxide layer, the first surface of the metal plate is subjected to alkali treatment.
(Section 14)
In forming the metal oxide layer, the alkali treatment is performed by immersing it in an aqueous solution of 3% to 10% sodium hydroxide or potassium hydroxide for 5 minutes to 10 minutes, and then at 100° C. to 200° C. for 5 minutes or more. Item 14. The method for manufacturing a wiring board according to Item 13, wherein heating is performed for 10 minutes or less.
(Section 15)
15. The method for manufacturing a wiring board according to any one of Items 1 to 14, wherein in forming the metal oxide layer, the metal oxide layer is formed to have a thickness of 0.1 μm or more and 10 μm or less.
(Section 16)
In preparing the metal plate, the height of the convex portion is 105 μm or more and 600 μm or less,
The wiring board according to any one of Items 1 to 15, wherein the part of the second surface of the metal plate is removed so that the thickness of the metal block is 100 μm or more and 500 μm or less. Production method.
(Section 17)
Preparing a wiring board manufactured by the method for manufacturing a wiring board according to any one of Items 1 to 16;
arranging a plurality of light sources including a light emitting element having a pair of element electrodes on the wiring board;
A method for manufacturing a light emitting device, wherein, in arranging the light source, each of the pair of element electrodes is connected to each of the adjacent metal blocks via a conductive member.
(Section 18)
18. The method for manufacturing a light emitting device according to item 17, further comprising dividing into pieces so as to include one light source.
(Section 19)
A plurality of metal blocks having an upper surface, a lower surface opposite to the upper surface, and a side surface continuous with the upper surface and the lower surface, and spaced apart in at least one of the row and column directions;
an inorganic light reflective member disposed on the side surface of the metal block and forming a flat plate shape together with the metal block,
A wiring board, wherein a metal oxide layer is formed on the side surface of the metal block facing the light reflective member.
(Section 20)
20. The wiring board according to item 19, wherein the upper surface, the lower surface, and the four side surfaces of the metal block are all rectangular.
(Section 21)
21. The wiring board according to item 19 or 20, wherein the base material of the metal block is copper, and the metal oxide layer is a copper oxide layer.
(Section 22)
The light reflective member contains at least one of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or a mixture of one or more of these. The wiring board according to any one of Items 19 to 22.
(Section 23)
23. The wiring board according to any one of Items 19 to 22, wherein the distance between the adjacent metal blocks is 100 μm or more and 300 μm or less.
(Section 24)
24. The wiring board according to any one of Items 19 to 23, wherein the metal block has a maximum diameter of 100 μm or more and 800 μm or less of the upper surface and the lower surface, and a thickness of 100 μm or more and 500 μm or less.
(Section 25)
The wiring board according to any one of Items 19 to 24,
a light source including a light emitting element disposed on the upper surface of the wiring board and having a pair of element electrodes;
In the light emitting device, each of the pair of element electrodes is connected to each of the adjacent metal blocks via a conductive member.
(Section 26)
26. The light emitting device according to item 25, wherein a plurality of the light sources are arranged.

1 Wiring board 10 Metal plate 11 Flat plate 12 Flat plate (modified example)
14 Convex portion 15 Metal block 15A Top surface 15B Bottom surface 15C Side surface 16 Metal oxide layer 17 Plating layer 18 Metal block (modified example)
20 Light source 21 Element electrode 22 Light emitting element 25 Resin member 30 Transparent member 40 Light reflective member 41 Light reflective member (uncured)
50 Conductive member 60 Covering member 81 Mask 82 Mask (modified example)
85 Dry film 100 Light emitting device (first embodiment)
200 Light emitting device (second embodiment)
300 Light emitting device (CSP)

Claims (26)

preparing a metal plate having a first surface having a plurality of convex portions spaced apart from each other and a second surface opposite to the first surface;
forming a metal oxide layer on the first surface of the metal plate;
disposing an uncured inorganic light-reflecting member on the first surface of the metal plate on which the metal oxide layer is formed;
Curing the disposed light reflective member;
removing a portion of the cured light reflective member;
exposing the base metal of the metal plate on the upper surface of the convex portion by removing a part of the light reflective member;
removing a part of the second surface side of the metal plate;
A method for manufacturing a wiring board, comprising: exposing the light reflective member between adjacent metal blocks by removing a portion of the second surface of the metal plate. 2. The method of manufacturing a wiring board according to claim 1, wherein in preparing the metal plate, the convex portion is formed by placing a mask on the metal plate and etching it. 2. The method of manufacturing a wiring board according to claim 1, wherein in preparing the metal plate, the convex portion is formed by placing a dry film on the metal plate and plating with metal. 2. The method of manufacturing a wiring board according to claim 1, wherein in preparing the metal plate, the protrusions are arranged in row and column directions, and the upper surfaces of the protrusions are rectangular in plan view. 5. The method for manufacturing a wiring board according to claim 4, wherein in preparing the metal plate, a distance between adjacent convex portions is 100 μm or more and 300 μm or less. 2. The method of manufacturing a wiring board according to claim 1, wherein in preparing the metal plate, a base material of the metal plate is copper. 4. The method of manufacturing a wiring board according to claim 3, wherein in preparing the metal plate, the metal plating is copper plating. In arranging the light reflective member, the light reflective member is made of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or one of these. The method for manufacturing a wiring board according to claim 1, comprising at least one kind of a mixture of at least one kind. 2. The method of manufacturing a wiring board according to claim 1, wherein in arranging the light reflective member, the light reflective member is arranged so as to cover at least a side surface of the convex portion. 2. The method for manufacturing a wiring board according to claim 1, wherein in arranging the light reflective member, the light reflective member contains either sodium metasilicate or aluminum phosphate as a curing agent. 2. The method for manufacturing a wiring board according to claim 1, wherein in curing the light reflective member, temporary curing is performed at 50°C or more and 200°C or less, and then main curing is performed at 200°C or more and 500°C or less. The method for manufacturing a wiring board according to claim 11, wherein in curing the light reflective member, the temporary curing and the main curing are performed at 0.5 MPa or more and 3 MPa or less. The method for manufacturing a wiring board according to claim 1, wherein in forming the metal oxide layer, the first surface of the metal plate is subjected to alkali treatment. The method for manufacturing a wiring board according to claim 13, wherein in forming the metal oxide layer, the alkali treatment is performed by immersing the substrate in an aqueous solution of sodium hydroxide or potassium hydroxide having a concentration of 3% to 10% for 5 to 10 minutes, and then heating the substrate at a temperature of 100°C to 200°C for 5 to 10 minutes. 2. The method for manufacturing a wiring board according to claim 1, wherein in forming the metal oxide layer, the metal oxide layer is formed to have a thickness of 0.1 μm or more and 10 μm or less. In preparing the metal plate, the height of the protrusion is 105 μm or more and 600 μm or less;
2 . The method for manufacturing a wiring board according to claim 1 , wherein the part of the second surface side of the metal plate is removed so that the thickness of the metal block is 100 μm or more and 500 μm or less. Preparing a wiring board manufactured by the method for manufacturing a wiring board according to any one of claims 1 to 16;
Arranging a plurality of light sources, including a light emitting element having a pair of element electrodes, on the wiring substrate;
In arranging the light source, each of the pair of element electrodes is connected to each of the adjacent metal blocks via a conductive member. 18. The method of manufacturing a light emitting device according to claim 17, further comprising dividing the light source into pieces so as to include one light source. A plurality of metal blocks having an upper surface, a lower surface opposite to the upper surface, and a side surface continuous with the upper surface and the lower surface, and arranged at intervals in at least one of the row and column directions;
an inorganic light-reflecting member disposed on the side surface of the metal block and having a flat plate shape together with the metal block;
A wiring board, wherein a metal oxide layer is formed on the side surface of the metal block facing the light reflective member. 20. The wiring board according to claim 19, wherein the upper surface, the lower surface, and the four side surfaces of the metal block are all rectangular. The wiring board according to claim 19, wherein the base material of the metal block is copper, and the metal oxide layer is a copper oxide layer. The light reflective member contains at least one of boron nitride, silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, or a mixture of one or more of these. The wiring board according to claim 19. The wiring board according to claim 19, wherein a distance between adjacent metal blocks is 100 μm or more and 300 μm or less. 20. The wiring board according to claim 19, wherein the metal block has a maximum diameter of 100 μm or more and 800 μm or less of the upper surface and the lower surface, and a thickness of 100 μm or more and 500 μm or less. The wiring board according to any one of claims 19 to 24,
a light source including a light emitting element disposed on the upper surface of the wiring board and having a pair of element electrodes;
In the light emitting device, each of the pair of element electrodes is connected to each of the adjacent metal blocks via a conductive member. The light emitting device according to claim 25, wherein a plurality of said light sources are arranged.

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