Light source and substrate

Abstract

To provide a light source and a substrate capable of improving heat dissipation.SOLUTION: A light source includes a substrate, a light emitting device, and a first bonding member. The first bonding member is disposed between a first electrode of the light emitting device and a first upper surface of a first metal member of the substrate to bond the first electrode and the first metal member, and is disposed between a second electrode of the light emitting device and a second upper surface of a second metal member of the substrate to bond the second electrode and the second metal member. An upper portion of an insulating member of the substrate is located between the first electrode and the second electrode of the light emitting device. Each of a first lower surface of the first metal member, a second lower surface of the second metal member, and a lower portion of the insulating member are exposed.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a light source and a substrate. [Background technology]

[0002] Patent Document 1 discloses a configuration in which an insulating protrusion is provided between a first electrode and a second electrode of an LED chip. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-102279 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a light source and a substrate that can improve heat dissipation. [Means for solving the problem]

[0005] According to one aspect of the present invention, a light source includes a substrate, a light-emitting device disposed on the substrate, and a first bonding member disposed between the substrate and the light-emitting device. The substrate includes a first metal member having a first upper surface and a first lower surface opposite the first upper surface, a second metal member having a second upper surface and a second lower surface opposite the second upper surface and spaced apart from the first metal member in a first direction, and an insulating member having a lower portion located between the first metal member and the second metal member in the first direction and an upper portion extending from the lower portion above the first upper surface and the second upper surface. The light-emitting device includes a semiconductor stack having a first element surface facing the substrate and a second element surface opposite the first element surface, a first electrode disposed on the first element surface, and a second electrode disposed on the first element surface spaced apart from the first electrode in the first direction. The first bonding member is disposed between the first electrode and the first upper surface of the first metal member to bond the first electrode to the first metal member, and is disposed between the second electrode and the second upper surface of the second metal member to bond the second electrode to the second metal member. The upper portion of the insulating member is located between the first electrode and the second electrode of the light emitting device in the first direction. The first lower surface of the first metal member, the second lower surface of the second metal member, and the lower portion of the insulating member are each exposed.

[0006] According to one aspect of the present invention, a substrate includes a first metal member having a first upper surface and a first lower surface opposite the first upper surface; a second metal member having a second upper surface and a second lower surface opposite the second upper surface, the second metal member being spaced apart from the first metal member in a first direction; and an insulating member having a lower portion located between the first metal member and the second metal member in the first direction and an upper portion extending from the lower portion above the first upper surface and the second upper surface. The width of the lower portion of the insulating member in the first direction is greater than the width of the upper portion of the insulating member in the first direction. The lower portion of the insulating member has a first lower side surface facing an inner surface of the first metal member and a second lower side surface facing an inner surface of the second metal member. The substrate further includes a joining member that joins the inner surface of the first metal member to the first lower side surface and joins the inner surface of the second metal member to the second lower side surface, and is located on the upper surface of the lower portion of the insulating member. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to provide a light source and a substrate that can improve heat dissipation. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a schematic plan view of a light source according to the embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 10 is a schematic cross-sectional view of a light source according to a modified example of the embodiment. [Figure 4] FIG. 2 is a schematic plan view illustrating one step of a method for manufacturing a substrate according to an embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view taken along line VV in FIG. [Figure 6] 5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. [Figure 7] 5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. [Figure 8]5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. [Figure 9] 5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. [Figure 10] 5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. [Figure 11] 5A to 5C are schematic cross-sectional views illustrating a step of a method for manufacturing a substrate according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments shown below are examples for embodying the technical concept of the present invention and are not limited thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of components described in the embodiments are not intended to limit the scope of the present disclosure, but are merely illustrative examples. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and detailed description will be omitted as appropriate. Furthermore, as cross-sectional views, end views showing only the cut surface may be used.

[0010] In the following description, terms indicating specific directions or positions (e.g., "above," "below," and other terms including these terms) may be used. However, these terms are used merely to facilitate understanding of relative directions or positions in the referenced drawings. As long as the relative direction or position relationship indicated by terms such as "above" and "below" in the referenced drawings is the same, the arrangement in drawings other than those disclosed herein, actual products, etc., does not necessarily have to be the same as in the referenced drawings. In this specification, the positional relationship expressed as "above (or below)" includes, for example, when two components are assumed to exist, a case in which the two components are in contact with each other, and a case in which the two components are not in contact with each other and one component is located above (or below) the other component. Furthermore, in this specification, unless otherwise specified, a component covering an object to be covered includes a case in which the component is in contact with the object to be covered and directly covers it, and a case in which the component is not in contact with the object to be covered and indirectly covers it. Furthermore, in this specification, a width in a specific direction refers to the maximum width in that specific direction.

[0011] In the figures shown below, the direction along the X axis is referred to as the first direction X, which indicates a predetermined direction in a plane parallel to the light-emitting surface of the light source according to the embodiment. The direction along the Y axis is referred to as the second direction Y, which is perpendicular to the first direction X in the plane parallel to the light-emitting surface. The direction along the Z axis is referred to as the third direction Z, which is perpendicular to the light-emitting surface.

[0012] [light source] A light source 1 according to the first embodiment will be described with reference to Figures 1 and 2. The light source 1 includes a substrate 10, a light emitting device 30 disposed on the substrate 10, and a first bonding member 41 disposed between the substrate 10 and the light emitting device 30.

[0013] <Light-emitting device> The light emitting device 30 has a semiconductor stack 33, a first electrode 31, and a second electrode 32. The light emitting device 30 is, for example, an LED (Light Emitting Diode), or may be an LD (Laser Diode).

[0014] The semiconductor laminate 33 has a first element surface 33A facing the substrate 10 and a second element surface 33B located on the opposite side of the first element surface 33A in the third direction Z.

[0015] The semiconductor stack 33 includes a nitride semiconductor. In this specification, the nitride semiconductor is, for example, In x Al y Ga 1-x-y The term "nitride semiconductor" includes semiconductors of all compositions in which the composition ratios x and y in the chemical formula represented by N (0≦x≦1, 0≦y≦1, x+y≦1) are varied within their respective ranges. Furthermore, nitride semiconductors also include those in the above chemical formula that further contain a Group V element other than N (nitrogen), and those that further contain various elements added to control various physical properties such as the conductivity type of the semiconductor. The semiconductor stack 33 includes an n-side semiconductor layer, a p-side semiconductor layer, and an active layer located between the n-side semiconductor layer and the p-side semiconductor layer. The active layer is a light-emitting layer that emits light and has, for example, an MQW (Multiple Quantum Well) structure including multiple barrier layers and multiple well layers. The light emitted by the active layer is, for example, visible light or ultraviolet light.

[0016] The first electrode 31 is disposed on the first element surface 33A. The second electrode 32 is disposed on the first element surface 33A and spaced apart from the first electrode 31 in the first direction X. The first electrode 31 is a cathode electrode in the light emitting device 30, and is electrically connected to the n-side semiconductor layer in the semiconductor laminate 33. The second electrode 32 is an anode electrode in the light emitting device 30, and is electrically connected to the p-side semiconductor layer in the semiconductor laminate 33. Examples of materials that can be used for the first electrode 31 and the second electrode 32 include gold, platinum, silver, aluminum, nickel, and titanium.

[0017] The light emitting device 30 may have an element substrate such as a sapphire substrate, a gallium nitride substrate, or a silicon substrate on the second element surface 33B of the semiconductor laminate 33. For example, if the element substrate is a sapphire substrate, the element substrate may be removed by a laser lift-off method, and the light emitting device 30 may not have an element substrate.

[0018] <Substrate> The substrate 10 has a first metal member 11, a second metal member 12, and an insulating member 20. The substrate 10 supports the light emitting device 30. The substrate 10 also serves as a wiring member that electrically connects the light emitting device 30 to an external circuit.

[0019] The first metal member 11 has a first upper surface 11A and a first lower surface 11B. The first upper surface 11A faces the first electrode 31 of the light emitting device 30 in the third direction Z. The first lower surface 11B is located on the opposite side of the first upper surface 11A in the third direction Z. The first metal member 11 also has an inner surface 11C and an outer surface 11D located on the opposite side of the inner surface 11C in the first direction X.

[0020] The second metal member 12 has a second upper surface 12A and a second lower surface 12B. The second upper surface 12A faces the second electrode 32 of the light emitting device 30 in the third direction Z. The second lower surface 12B is located on the opposite side of the second upper surface 12A in the third direction Z. The second metal member 12 also has an inner surface 12C facing the inner surface 11C of the first metal member 11 in the first direction X, and an outer surface 12D located on the opposite side of the inner surface 12C in the first direction X.

[0021] The first metal member 11 may include a plating 13 facing the first electrode 31 in the third direction Z, and the surface of the plating 13 may be the first upper surface 11A. The first metal member 11 may include a plating 15 located on the opposite side of the plating 13 in the third direction Z, and the surface of the plating 15 may be the first lower surface 11B. The second metal member 12 may include a plating 14 facing the second electrode 32 in the third direction Z, and the surface of the plating 14 may be the second upper surface 12A. The second metal member 12 may include a plating 16 located on the opposite side of the plating 14 in the third direction Z, and the surface of the plating 16 may be the second lower surface 12B. By including plating in the first metal member 11 and the second metal member 12, the first bonding member 41 described below is less likely to diffuse into the first metal member 11 and the second metal member 12, and the generation of voids in the first bonding member 41 can be reduced. The platings 13, 14, 15, and 16 contain at least one metal selected from, for example, nickel (Ni), palladium (Pd), titanium (Ti), platinum (Pt), and gold (Au). Among these, nickel is effective in preventing the diffusion of the first bonding members 41. If the first bonding members 41 do not easily wet and spread over the nickel, palladium or gold can be further formed on the nickel to make it easier for the first bonding members 41 to wet and spread over the nickel.

[0022] 1, the first metal member 11 and the second metal member 12 are positioned apart from each other in a first direction X. The first metal member 11 and the second metal member 12 extend in a second direction Y. The first metal member 11 and the second metal member 12 contain, for example, at least one metal selected from copper (Cu) and aluminum (Al).

[0023] The insulating member 20 has a lower portion 22 and an upper portion 21. The upper portion 21 is located above the lower portion 22 in the third direction Z. The lower portion 22 and the upper portion 21 extend in the second direction Y. The insulating member 20 is made of, for example, ceramics. The insulating member 20 is, for example, a ceramic sintered body in which the lower portion 22 and the upper portion 21 are integrally formed. The insulating member 20 includes, for example, silicon nitride, aluminum oxide, aluminum nitride, silicon carbide, or silicon oxide. Alternatively, the insulating member 20 may be a metal coated with ceramics, glass, or resin.

[0024] The lower portion 22 of the insulating member 20 is located between the first metal member 11 and the second metal member 12 in the first direction X. The lower portion 22 has a first lower side surface 22A facing the inner side surface 11C of the first metal member 11 and a second lower side surface 22B facing the inner side surface 12C of the second metal member 12.

[0025] The upper part 21 extends from the lower part 22 upward in the third direction Z above the first upper surface 11A of the first metal member 11 and the second upper surface 12A of the second metal member 12. The upper part 21 has an upper surface 21C facing the first element surface 33A of the semiconductor laminate 33. The portion of the upper part 21 on the upper surface 21C side is located between the first electrode 31 and the second electrode 32 of the light emitting device 30 in the first direction X. The upper part 21 has a first upper side surface 21A facing the inner surface of the first electrode 31 and a second upper side surface 21B facing the inner surface of the second electrode 32.

[0026] The lower part 22 has a lower surface 22D located on the opposite side of the upper surface 21C of the upper part 21 in the third direction Z. The first lower surface 11B of the first metal member 11, the second lower surface 12B of the second metal member 12, and the lower surface 22D of the lower part 22 of the insulating member 20 are each exposed.

[0027] The light source 1 can be disposed on a mounting substrate. The first lower surface 11B of the first metal member 11, the second lower surface 12B of the second metal member 12, and the lower surface 22D of the lower part 22 of the insulating member 20 face the mounting surface of the mounting substrate. The first lower surface 11B of the first metal member 11 and the second lower surface 12B of the second metal member 12 are joined to the wiring portion of the mounting substrate by a joining member such as solder. This electrically connects the first metal member 11 and the second metal member 12 to the wiring portion of the mounting substrate.

[0028] The width in the first direction X of the upper part 21 of the insulating member 20 disposed between the first electrode 31 and the second electrode 32 of the light emitting device 30 is smaller than the width in the first direction X between the first electrode 31 and the second electrode 32. The width in the first direction X of the lower part 22 of the insulating member 20 is larger than the width in the first direction X of the upper part 21 of the insulating member 20. This makes it possible to make the separation distance in the first direction X between the first lower surface 11B of the first metal member 11 and the second lower surface 12B of the second metal member 12 larger than the distance between the electrodes of the light emitting device 30, and makes it less likely that a short circuit will occur between the first lower surface 11B and the second lower surface 12B by the bonding member on the mounting board.

[0029] <First joining member> The first bonding members 41 are conductive. For example, solder can be used as the first bonding members 41. The solder contains, for example, a gold-tin alloy. Alternatively, a mixture of resin and metal particles can be used as the first bonding members 41. For example, silver particles can be used as the metal particles.

[0030] The first bonding member 41 is disposed between the first electrode 31 of the light emitting device 30 and the first upper surface 11A of the first metal member 11, and bonds the first electrode 31 and the first metal member 11. When the first metal member 11 includes plating 13, the first bonding member 41 is bonded to the plating 13. The first electrode 31 is electrically connected to the first metal member 11 via the first bonding member 41.

[0031] The first bonding member 41 is disposed between the second electrode 32 of the light emitting device 30 and the second upper surface 12A of the second metal member 12, and bonds the second electrode 32 and the second metal member 12. When the second metal member 12 includes plating 14, the first bonding member 41 is bonded to the plating 14. The second electrode 32 is electrically connected to the second metal member 12 via the first bonding member 41.

[0032] The semiconductor stack 33 including the active layer in the light emitting device 30 generates heat as it emits light. The heat generated by the semiconductor stack 33 is dissipated to the first metal member 11 via the first electrode 31 and the first bonding member 41, and is dissipated to the second metal member 12 via the second electrode 32 and the first bonding member 41.

[0033] Furthermore, according to this embodiment, heat generated by the semiconductor stack 33 can be transferred to the insulating member 20. The heat transferred from the semiconductor stack 33 to the insulating member 20 can be transferred to the first electrode 31, the second electrode 32, the first metal member 11, and the second metal member 12, which are made of a metal material having a higher thermal conductivity than the insulating member 20. Furthermore, when the lower surface 22D of the lower part 22 contacts the mounting surface of the mounting board, heat can be transferred directly from the insulating member 20 to the mounting board.

[0034] The inter-electrode region between the first electrode 31 and the second electrode 32 on the first element surface 33A of the semiconductor laminate 33 cannot dissipate heat to the substrate 10 via the first electrode 31 and the second electrode 32, and is therefore more prone to heat concentration than the region where the first electrode 31 and the second electrode 32 are disposed. According to this embodiment, heat can be dissipated to the substrate 10 via the insulating member 20 in such an inter-electrode region. Heat generated by the semiconductor laminate 33 can be efficiently transferred to the substrate 10 by dispersing it via the first electrode 31, the second electrode 32, and the insulating member 20, making it less likely for heat to concentrate in the inter-electrode region of the semiconductor laminate 33. This reduces the temperature (junction temperature) of the active layer, improving light-emitting efficiency and reliability. Furthermore, improved reliability allows for increased input power and improved light output.

[0035] It is preferable that the first joint member 41 joins the inner surface of the first electrode 31 to an upper part of the first upper side surface 21A of the insulating member 20, and joins the inner surface of the second electrode 32 to an upper part of the second upper side surface 21B of the insulating member 20. This makes it easier to transfer heat from the insulating member 20 to the first electrode 31 and the second electrode 32 via the first joint member 41.

[0036] The upper surface 21C of the upper portion 21 of the insulating member 20 may be in contact with the first element surface 33A of the semiconductor laminate 33 directly or via a thermally conductive adhesive layer. This makes it easier to transfer heat generated by the semiconductor laminate 33 to the insulating member 20. As the thermally conductive adhesive layer, for example, a resin layer in which ceramics is dispersed, or a ceramic adhesive layer can be used.

[0037] The substrate 10 may further include a second bonding member 42. The second bonding member 42 bonds the inner surface 11C of the first metal member 11 to the first lower side surface 22A of the insulating member 20, and bonds the inner surface 12C of the second metal member 12 to the second lower side surface 22B of the insulating member 20. This makes it easier to transfer heat from the insulating member 20 to the first metal member 11 and the second metal member 12 via the second bonding member 42.

[0038] The second bonding members 42 contain at least one metal selected from the group consisting of copper (Cu), chromium (Cr), nickel (Ni), silver (Ag), aluminum (Al), zinc (Zn), tin (Sn), titanium (Ti), cerium (Ce), zirconium (Zr), and magnesium (Mg). The second bonding members 42 may contain a compound or alloy of the above metals.

[0039] The lower portion 22 of the insulating member 20 further has an upper surface 22C. The upper surface 22C connects the first upper side surface 21A to the first lower side surface 22A, and connects the second upper side surface 21B to the second lower side surface 22B. The upper surface 22C connecting the first upper side surface 21A to the first lower side surface 22A faces the first electrode 31 in the third direction Z. The upper surface 22C connecting the second upper side surface 21B to the second lower side surface 22B faces the second electrode 32 in the third direction Z.

[0040] The second joint member 42 can further be located on the upper surface 22C of the lower portion 22 of the insulating member 20, below the first upper side surface 21A, and below the second upper side surface 21B. The second joint member 42 is disposed continuously below the first upper side surface 21A, the upper surface 22C, and the first lower side surface 22A, and is disposed continuously below the second upper side surface 21B, the upper surface 22C, and the second lower side surface 22B. This makes it easier to transfer heat from the insulating member 20 to the first metal member 11 and the second metal member 12 via the second joint member 42.

[0041] The second bonding member 42 and the first bonding member 41 are disposed between the upper surface 22C of the lower portion 22 of the insulating member 20 and each of the first electrode 31 and the second electrode 32. Furthermore, when the first metal member 11 includes plating 13, the plating 13 is disposed between the second bonding member 42 and the first bonding member 41. Between the upper surface 22C of the lower portion 22 of the insulating member 20 and the first electrode 31, the first bonding member 41 contacts the first electrode 31 and the second electrode 32, the first bonding member 41 and the second bonding member 42 contact each other directly or via the plating 13, and the second bonding member 42 contacts the upper surface 22C of the lower portion 22 of the insulating member 20. This makes it easier for heat transferred from the semiconductor stack 33 to the first electrode 31 and the second electrode 32 to be dissipated to the insulating member 20 as well.

[0042] The upper surface 21C of the upper portion 21 of the insulating member 20 is exposed from the second bonding member 42. This makes it difficult for the first bonding member 41 to wet and spread over the upper surface 21C, making it difficult for a short circuit to occur between the first electrode 31 and the second electrode 32 via the first bonding member 41.

[0043] On the underside of the substrate 10, the underside 22D of the lower part 22 of the insulating member 20 is exposed from the second bonding member 42. This makes it difficult for the bonding member to wet and spread onto the underside 22D when bonding the light source 1 to the mounting board, making it less likely for a short circuit to occur between the first metal member 11 and the second metal member 12 via the bonding member. Furthermore, the width in the first direction X of the underside 22D of the lower part 22 is greater than the width in the first direction X of the upper surface 21C of the upper part 21. This makes it even less likely for a short circuit to occur between the first metal member 11 and the second metal member 12.

[0044] The insulating member 20 further has a metal compound layer 18 on the first lower side surface 22A, the second lower side surface 22B, the upper surface 22C of the lower portion 22, the first upper side surface 21A, and the second upper side surface 21B. The metal compound layer 18 can improve the adhesion between the insulating member 20 and the first bonding member 41 and between the insulating member 20 and the second bonding member 42, and can make it difficult for gaps to form between the insulating member 20 and the first bonding member 41 and between the insulating member 20 and the second bonding member 42. This can facilitate heat transfer between the insulating member 20 and the first electrode 31, between the insulating member 20 and the second electrode 32, between the insulating member 20 and the first metal member 11, and between the insulating member 20 and the second metal member 12.

[0045] When the insulating member 20 is a nitride, the metal compound layer 18 can be a metal nitride layer due to a thermal reaction between the insulating member 20 and the metal contained in the second bonding member 42, which will be described in the manufacturing method below. For example, the insulating member 20 contains silicon nitride, the second bonding member 42 contains titanium or a titanium compound, and the metal compound layer 18 is a titanium nitride layer.

[0046] Alternatively, if insulating member 20 is an oxide, metal compound layer 18 can be a metal oxide layer.

[0047] Alternatively, if the insulating member 20 is a carbide, the metal compound layer 18 can be a metal carbide layer.

[0048] The light source 1 may include a light-transmitting member 34 on the upper surface of the light-emitting device 30 (the second element surface 33B of the semiconductor laminate 33 or the upper surface of the element substrate). The light-transmitting member 34 and the upper surface of the light-emitting device 30 are bonded together via a light-transmitting resin layer. Alternatively, the light-transmitting member 34 and the light-emitting surface of the light-emitting device 30 may be bonded together directly.

[0049] The light-transmitting member 34 can be, for example, a wavelength conversion member, a glass member, a ceramic member, a resin member, or the like. The light-transmitting member 34 can be flat, lens-shaped, or have an uneven shape on at least one surface. The wavelength conversion member converts the wavelength of at least a portion of the light emitted by the active layer of the semiconductor laminate 33. The wavelength conversion member can be a sintered body formed by sintering phosphor powder and consisting essentially of phosphor alone. Alternatively, the wavelength conversion member can be a light-transmitting material containing phosphor. The light-transmitting material can be, for example, ceramic, resin, or glass. The phosphor can be, for example, a cerium-activated yttrium-aluminum-garnet phosphor (e.g., (Y,Gd)3(Al,Ga)5O 12 :Ce), cerium-activated lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce) and the like can be used.

[0050] The light source 1 may further include a covering member 50. The covering member 50 may be reflective to the light emitted by the active layer. For example, the covering member 50 includes a light-transmitting base material and light-reflective particles dispersed in the base material. The base material may be made of resin, glass, or ceramic. The light-reflective particles may be made of titanium oxide, silicon oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, or zirconium oxide. If the light-emitting device 30 is an LD, the covering member 50 may be omitted.

[0051] The outer surface 11D of the first metal member 11 and the outer surface 12D of the second metal member 12 are preferably exposed from the covering member 50. The bonding material used to bond the light source 1 to the mounting board can wet and rise onto the exposed outer surfaces 11D and 12D. This allows heat generated by the light emitting device 30 to be dissipated to the mounting board from the outer surface 11D of the first metal member 11 via the bonding material, and from the outer surface 12D of the second metal member 12 via the bonding material.

[0052] 3, a portion 11E of the first metal member 11 may be located between the first electrode 31 and an upper surface 22C of the lower portion 22 of the insulating member 20, and a portion 12E of the second metal member 12 may be located between the upper surface 22C of the lower portion 22 of the insulating member 20 and the second electrode 32. This increases the area where the first electrode 31 and the first metal member 11 face each other, and the area where the second electrode 32 and the second metal member 12 face each other, thereby improving heat dissipation from the first electrode 31 and the second electrode 32 to the first metal member 11 and the second metal member 12.

[0053] [Substrate manufacturing method] An example of a method for manufacturing the substrate 10 will be described with reference to FIGS.

[0054] 4 and 5, the method for manufacturing the substrate 10 includes a step of preparing a ceramic sintered body 100. Fig. 5 is a schematic cross-sectional view taken along line VV in Fig. 4.

[0055] The ceramic sintered body 100 has a plurality of insulating members 20 extending in the second direction Y and arranged at a distance from each other in the first direction X. A through-hole portion 60 extending in the second direction Y is located between adjacent insulating members 20 in the first direction X. As shown in FIG. 5 , the through-hole portion 60 has a first hole portion 61 adjacent to the upper portion 21 of the insulating member 20 and a second hole portion 62 adjacent to the lower portion 22 of the insulating member 20. The first hole portion 61 and the second hole portion 62 are connected in the third direction Z. The width of the first hole portion 61 in the first direction X is larger than the width of the second hole portion 62 in the first direction X. For example, the ends of the plurality of insulating members 20 in the second direction Y are integrally connected to a connecting member extending in the first direction X.

[0056] The step of preparing the ceramic sintered body 100 can include a step of forming through-holes 60 in a ceramic plate that is a sintered body that has been subjected to a firing treatment, for example, by a method such as laser processing or blade processing. By forming through-holes 60 in a ceramic plate that is a sintered body by the above processing method, it is possible to form a plurality of insulating members 20 with reduced variation in shape.

[0057] The method for manufacturing the substrate 10 includes a step of filling the through-holes 60 with a metal paste 110, as shown in FIG.

[0058] The metal paste 110 contains at least one metal selected from the group consisting of copper (Cu), chromium (Cr), nickel (Ni), silver (Ag), aluminum (Al), zinc (Zn), tin (Sn), titanium (Ti), cerium (Ce), zirconium (Zr), and magnesium (Mg). The metal paste 110 may also contain a compound or alloy of any of the above metals. The metal paste 110 may also contain an activated metal powder. The activated metal powder may be at least one selected from the group consisting of TiH2, CeH2, ZrH2, and MgH2. The metal paste 110 may also contain an organic solvent. The viscosity of the metal paste 110 can be adjusted by adjusting the type and amount of the organic solvent. Examples of the organic solvent that can be used include resins such as acrylic, epoxy, urethane, ethyl cellulose, silicone, phenol, polyimide, polyurethane, melamine, and urea. The metal paste 110 may also contain an inorganic filler. The inclusion of an inorganic filler in the metal paste 110 can reduce volume shrinkage during a firing process, which will be described later. Examples of inorganic fillers that can be used include aluminum nitride (AlN), silicon nitride (Si3N4), and aluminum oxide (Al2O3). For example, the metal paste 110 preferably contains 60% to 99% by weight of a silver-copper alloy with a silver (Ag) to copper (Cu) mixing ratio of 72:28, 0.5% to 10% by weight of titanium hydride (TiH2) as a metal active powder, 0.1% to 10% by weight of an organic binder, and 1% to 20% by weight of an inorganic filler.

[0059] As shown in FIG. 7 , the manufacturing method of the substrate 10 includes a step of arranging metal bodies 120 in a metal paste 110. The metal bodies 120 extend in the second direction Y. A plurality of metal bodies 120 can be prepared from a metal plate by, for example, punching, laser processing, etching, or other methods. The cross-sectional shape, top surface shape, and bottom surface shape of the metal bodies 120 are rectangular or square. This allows a plurality of metal bodies 120 with reduced shape variation to be prepared from the metal plate by the above method. In a step described below, the metal body 120 is diced along the first direction X and the second direction Y in a plan view, thereby separating the metal body 120 into the first metal member 11 and the second metal member 12 described above.

[0060] 8, after arranging the metal body 120 on the metal paste 110, the manufacturing method of the substrate 10 may further include a step of forming the metal paste 110 so as to cover the upper surface of the metal body 120, the lower surface of the metal body 120, the upper surface 21C of the upper portion 21 of the insulating member 20, and the lower surface 22D of the lower portion 22 of the insulating member 20. This makes it possible to reduce volumetric shrinkage of the metal body (second bonding member 42) described below obtained by firing the metal paste 110.

[0061] The method for manufacturing substrate 10 includes a step of arranging metal body 120 in metal paste 110 and then firing metal paste 110 at a temperature of, for example, 780° C. to 850° C. The firing process evaporates the organic solvent in metal paste 110, and further melts the metal or alloy powder to form second bonding member 42, which is a continuous metal body.

[0062] For example, when the metal paste 110 is primarily composed of silver-copper alloy powder, the melting point of the silver-copper alloy powder is 780°C, which is lower than the melting points of copper powder (1084°C) and silver powder (962°C), and the firing process can be carried out at a lower temperature than when the metal paste 110 is primarily composed of copper powder or silver powder.

[0063] Furthermore, the firing process causes a thermal reaction between the metal contained in the metal paste 110 and the insulating member 20, and a metal compound layer 18 is formed on the surfaces of the insulating member 20 that were in contact with the metal paste 110 (the first upper side surface 21A, the second upper side surface 21B, the first lower side surface 22A, the second lower side surface 22B, and the top surface 22C of the lower portion 22). The metal compound layer 18 increases the bonding strength between the insulating member 20 and the second bonding member 42. For example, if the insulating member 20 contains silicon nitride and the metal paste 110 contains titanium hydride as the active metal powder, a titanium nitride layer is formed as the metal compound layer 18.

[0064] After the firing process, the second bonding members 42 covering the upper surface of the metal body 120, the lower surface of the metal body 120, the upper surface 21C of the upper portion 21 of the insulating member 20, and the lower surface 22D of the lower portion 22 of the insulating member 20 are removed by a polishing process. As a result, as shown in Fig. 9, the upper surface of the metal body 120, the lower surface of the metal body 120, the upper surface 21C of the upper portion 21 of the insulating member 20, and the lower surface 22D of the lower portion 22 of the insulating member 20 are exposed from the second bonding members 42. The metal body 120 is bonded to the first upper side surface 21A, the second upper side surface 21B, the first lower side surface 22A, and the second lower side surface 22B of the insulating member 20 by the second bonding members 42.

[0065] 10, after the firing treatment, the manufacturing method of the substrate 10 includes a step of removing a part of the upper surface of the metal body 120 and a part of the upper surface of the second bonding member 42 to expose a part of the first upper side surface 21A and a part of the second upper side surface 21B of the insulating member 20 from the second bonding member 42. For example, the metal body 120 and the second bonding member 42 can be removed by a method such as etching or blasting.

[0066] The metal compound layer 18 remains without being removed on the first upper side surface 21A and the second upper side surface 21B exposed from the second bonding member 42. This makes it easier for the first bonding member 41 to wet and spread over the metal compound layer 18.

[0067] The manufacturing method of the substrate 10 may, if necessary, include a step of forming plating 131 and plating 132, as shown in FIG. 11 . Plating 131 and plating 132 can be formed by electrolytic plating or electroless plating. Plating 131 is formed on the upper surface of the metal body 120, and plating 132 is formed on the lower surface of the metal body 120. When dicing the metal body 120, plating 131 is separated into plating 13 and plating 14 described above, and plating 132 is separated into plating 15 and plating 16 described above.

[0068] [Method of joining light-emitting device to substrate] A first bonding member 41 is supplied to the upper surface of the metal body 120 of the substrate 10 obtained in the above process, and the light emitting device 30 is placed on the substrate 10 so that the upper portion 21 of the insulating member 20 is located between the first electrode 31 and the second electrode 32 of the light emitting device 30. The first electrode 31 and the second electrode 32 are each placed on the first bonding member 41. There is a gap between the first upper side surface 21A of the insulating member 20 and the inner surface of the first electrode 31, and between the second upper side surface 21B of the insulating member 20 and the inner surface of the second electrode 32. In this state, a reflow process is performed to heat and melt the first bonding member 41.

[0069] The molten first bonding member 41 wets and spreads between the first electrode 31 and the metal body 120 and between the second electrode 32 and the metal body 120, and further wets up between the first upper side surface 21A of the insulating member 20 and the inner surface of the first electrode 31, and between the second upper side surface 21B of the insulating member 20 and the inner surface of the second electrode 32. When the first bonding member 41 hardens after the reflow process, the first electrode 31 is bonded to the metal body 120, the second electrode 32 is bonded to the metal body 120, the first electrode 31 is bonded to the upper part 21 of the insulating member 20, and the second electrode 32 is bonded to the upper part 21 of the insulating member 20.

[0070] Since the upper portion 21 of the insulating member 20 is positioned between the first electrode 31 and the second electrode 32 of the light emitting device 30, when the first bonding member 41 melts and becomes fluid during bonding, it is possible to restrict rotation of the light emitting device 30 in the XY plane and large positional deviation in the first direction X.

[0071] After bonding the light emitting device 30 to the substrate 10, the outer surface of the light emitting device 30 is covered with a covering member 50 as needed. Thereafter, the metal body 120 is diced along the first direction X and the second direction Y, and the insulating member 20 is also cut at dicing positions of the metal body 120 along the first direction X, thereby dividing the metal body 120 into a plurality of light sources 1.

[0072] Embodiments of the present invention can include the following light sources and substrates.

[0073] [Section 1] A substrate; a light emitting device disposed on the substrate; a first bonding member disposed between the substrate and the light emitting device; Equipped with The substrate is a first metal member having a first upper surface and a first lower surface located opposite the first upper surface; a second metal member having a second upper surface and a second lower surface located opposite the second upper surface, the second metal member being located away from the first metal member in the first direction; an insulating member having a lower portion located between the first metal member and the second metal member in the first direction, and an upper portion extending from the lower portion above the first upper surface and the second upper surface; and The light emitting device comprises: a semiconductor laminate having a first element surface facing the substrate and a second element surface located on the opposite side of the first element surface; a first electrode disposed on the first element surface; and a second electrode disposed on the first element surface and spaced apart from the first electrode in the first direction; and The first joining member is a first upper surface of the first metal member and a second upper surface of the first metal member; a second upper surface of the second metal member, the second upper surface being disposed between the second electrode and the second metal member, and the second upper surface being bonded to the second electrode and the second metal member; the upper portion of the insulating member is located between the first electrode and the second electrode of the light emitting device in the first direction; a light source in which the first lower surface of the first metal member, the second lower surface of the second metal member, and the lower portion of the insulating member are each exposed. [Section 2] the upper portion of the insulating member has a first upper side surface facing an inner surface of the first electrode and a second upper side surface facing an inner surface of the second electrode, Item 1. The light source described in item 1, wherein the first bonding member bonds the inner surface of the first electrode to an upper portion of the first upper side surface of the insulating member, and bonds the inner surface of the second electrode to an upper portion of the second upper side surface of the insulating member. [Section 3] the lower portion of the insulating member has a first lower side surface facing an inner surface of the first metal member and a second lower side surface facing an inner surface of the second metal member, Item 3. The light source described in item 2, wherein the substrate further has a second bonding member that bonds the inner surface of the first metal member to the first lower side surface and that bonds the inner surface of the second metal member to the second lower side surface. [Section 4] Item 4. The light source according to item 3, wherein the second bonding member is further provided on the upper surface of the lower portion of the insulating member, below the first upper side surface, and below the second upper side surface. [Section 5] 5. The light source according to any one of items 1 to 4, wherein the width of the lower portion of the insulating member in the first direction is greater than the width of the upper portion of the insulating member in the first direction. [Section 6] Item 5, which cites Item 3, is a light source according to Item 5, wherein a width of the lower portion of the insulating member in the first direction, which is exposed from the second bonding member on the lower surface of the substrate, is larger than a width of the upper portion of the insulating member in the first direction, which is exposed from the second bonding member. [Section 7] 7. The light source according to any one of items 1 to 6, wherein an upper surface of the upper portion of the insulating member is in contact with the first element surface of the light emitting device. [Section 8] Item 8. The light source according to any one of items 1 to 7, wherein the insulating member is made of ceramics. [Section 9] Item 5. The light source according to item 4, wherein the insulating member further has a metal compound layer on the first lower side surface, the second lower side surface, the upper surface of the lower portion of the insulating member, the first upper side surface, and the second upper side surface. [Section 10] the insulating member includes silicon nitride; the second bonding member contains titanium or a titanium compound, Item 10. The light source according to item 9, wherein the metal compound layer is a titanium nitride layer. [Section 11] 8. The light source according to any one of items 1 to 7, wherein the insulating member is a metal coated with ceramic, glass, or resin. [Section 12] a first metal member having a first upper surface and a first lower surface located opposite the first upper surface; a second metal member having a second upper surface and a second lower surface located opposite the second upper surface, the second metal member being located away from the first metal member in the first direction; an insulating member having a lower portion located between the first metal member and the second metal member in the first direction, and an upper portion extending from the lower portion above the first upper surface and the second upper surface; Equipped with a width of the lower portion of the insulating member in the first direction is greater than a width of the upper portion of the insulating member in the first direction; the lower portion of the insulating member has a first lower side surface facing an inner surface of the first metal member and a second lower side surface facing an inner surface of the second metal member, The substrate further has a joining member that joins the inner surface of the first metal member to the first lower side surface, and that joins the inner surface of the second metal member to the second lower side surface, and is located on the upper surface of the lower part of the insulating member. [Section 13] the insulating member is made of ceramic, Item 13. The substrate according to item 12, further comprising a metal compound layer at the interface between the insulating member and the bonding member.

[0074] The above describes embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. All forms that can be implemented by a person skilled in the art through appropriate design modifications based on the above-described embodiments of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention. In addition, a person skilled in the art may conceive of various modifications and alterations within the scope of the concept of the present invention, and these modifications and alterations also fall within the scope of the present invention. [Explanation of symbols]

[0075] 1...light source, 10...substrate, 11...first metal member, 11A...first upper surface, 11B...first lower surface, 12...second metal member, 12A...second upper surface, 12B...second lower surface, 13, 14, 15, 16...plating, 18...metal compound layer, 20...insulating member, 21...upper portion, 21A...first upper side surface, 21B...second upper side surface, 21C...upper surface of upper portion, 22...lower portion, 22A...first Lower side surface, 22B...second lower side surface, 22C...upper surface of lower portion, 22D...lower surface of lower portion, 30...light emitting device, 31...first electrode, 32...second electrode, 33...semiconductor laminate, 33A...first element surface, 33B...second element surface, 34...light-transmitting member, 41...first bonding member, 42...second bonding member, 50...covering member, 100...ceramic sintered body, 110...metal paste

Claims

1. A substrate; a light emitting device disposed on the substrate; a first bonding member disposed between the substrate and the light emitting device; Equipped with The substrate is a first metal member having a first upper surface and a first lower surface located opposite the first upper surface; a second metal member having a second upper surface and a second lower surface located opposite the second upper surface, the second metal member being located away from the first metal member in the first direction; an insulating member having a lower portion located between the first metal member and the second metal member in the first direction, and an upper portion extending from the lower portion above the first upper surface and the second upper surface; and The light emitting device comprises: a semiconductor laminate having a first element surface facing the substrate and a second element surface located on the opposite side of the first element surface; a first electrode disposed on the first element surface; and a second electrode disposed on the first element surface and spaced apart from the first electrode in the first direction; and The first joining member is a first electrode and a first upper surface of the first metal member, the first electrode and the first upper surface being disposed between the first electrode and the first metal member; a second metal member that is disposed between the second electrode and the second upper surface of the second metal member and that joins the second electrode and the second metal member; the upper portion of the insulating member is located between the first electrode and the second electrode of the light emitting device in the first direction; a light source in which the first lower surface of the first metal member, the second lower surface of the second metal member, and the lower portion of the insulating member are each exposed.

2. the upper portion of the insulating member has a first upper side surface facing an inner surface of the first electrode and a second upper side surface facing an inner surface of the second electrode, 2. The light source according to claim 1, wherein the first joining member joins the inner surface of the first electrode to an upper portion of the first upper side surface of the insulating member, and joins the inner surface of the second electrode to an upper portion of the second upper side surface of the insulating member.

3. the lower portion of the insulating member has a first lower side surface facing an inner surface of the first metal member and a second lower side surface facing an inner surface of the second metal member, The light source according to claim 2 , wherein the substrate further has a second joining member that joins the inner surface of the first metal member to the first lower side surface and that joins the inner surface of the second metal member to the second lower side surface.

4. The light source of claim 3 , wherein the second joining member is further provided on an upper surface of the lower portion of the insulating member, below the first upper side surface, and below the second upper side surface.

5. The light source according to claim 1 , wherein a width of the lower portion of the insulating member in the first direction is greater than a width of the upper portion of the insulating member in the first direction.

6. The light source described in claim 5, which cites claim 3, wherein a width of the lower portion of the insulating member in the first direction, which is exposed from the second bonding member on the underside of the substrate, is greater than a width of the upper portion of the insulating member in the first direction, which is exposed from the second bonding member.

7. The light source according to claim 1 , wherein an upper surface of the upper portion of the insulating member is in contact with the first element surface of the light emitting device.

8. The light source according to claim 1 , wherein the insulating member is made of ceramics.

9. The light source of claim 4 , wherein the insulating member further comprises a metal compound layer on the first lower side surface, the second lower side surface, the top surface of the lower portion of the insulating member, the first upper side surface, and the second upper side surface.

10. the insulating member includes silicon nitride; the second bonding member contains titanium or a titanium compound, 10. The light source of claim 9, wherein the metal compound layer is a titanium nitride layer.

11. 5. The light source according to claim 1, wherein the insulating member is a metal coated with ceramic, glass, or resin.

12. a first metal member having a first upper surface and a first lower surface located opposite the first upper surface; a second metal member having a second upper surface and a second lower surface located opposite the second upper surface, the second metal member being located away from the first metal member in the first direction; an insulating member having a lower portion located between the first metal member and the second metal member in the first direction, and an upper portion extending from the lower portion above the first upper surface and the second upper surface; Equipped with a width of the lower portion of the insulating member in the first direction is greater than a width of the upper portion of the insulating member in the first direction; the lower portion of the insulating member has a first lower side surface facing an inner surface of the first metal member and a second lower side surface facing an inner surface of the second metal member, The substrate further has a joining member that joins the inner surface of the first metal member to the first lower side surface, and that joins the inner surface of the second metal member to the second lower side surface, and is located on the upper surface of the lower part of the insulating member.

13. the insulating member is made of ceramic, The substrate according to claim 12 , further comprising a metal compound layer at an interface between the insulating member and the joining member.

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