Light-emitting modules and planar light sources

Abstract

To provide a thin light-emitting module.SOLUTION: A light-emitting module comprises: a substrate having a base material having a first surface and a second surface opposite the first surface, and having a hole penetrating from the first surface to the second surface and a wiring arranged on the first surface and including a first wiring, and in which the first wiring is positioned overlapping the hole in the top view; a semiconductor laminate with a top surface and a bottom surface opposite the top surface; and an electrode arranged on the bottom surface, and the light emitting element is positioned in the hole so that the bottom surface of the semiconductor laminate is positioned below the second surface.SELECTED DRAWING: Figure 1D

Description

[Technical Field]

[0001] This disclosure relates to a light-emitting module and a planar light source. [Background technology]

[0002] Light-emitting modules and planar light sources using multiple light sources are known. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Korean Patent Application No. 10-2009-0117419 [Patent Document 2] Japanese Patent Publication No. 2022-098041 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The objective is to provide a thin light-emitting module. [Means for solving the problem]

[0005] This disclosure includes the following components: A substrate having a first surface and a second surface opposite to the first surface, and having a hole that penetrates from the first surface to the second surface, and a wiring including a first wiring disposed on the first surface side, wherein the first wiring is positioned so as to overlap the hole when viewed from above, A semiconductor laminate having an upper surface and a lower surface opposite the upper surface, and an electrode disposed on the lower surface, is used as a light source including a light-emitting element. Equipped with, A light-emitting module in which the light-emitting element is arranged in the hole such that the lower surface of the semiconductor laminate is located below the second surface. [Effects of the Invention]

[0006] A thin light-emitting module can be realized.

Brief Description of the Drawings

[0007] [Figure 1A] It is a schematic top view showing an example of the light-emitting module according to the embodiment. [Figure 1B] It is a schematic top view enlarging the IB part of FIG. 1A. [Figure 1C] It is a schematic top view enlarging the IC part of FIG. 1B. [Figure 1D] It is a cross-sectional view showing a cross-section along the ID-ID line of FIG. 1C. [Figure 2A] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2B] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2C] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2D] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2E] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2F] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 2G] It is a schematic cross-sectional view showing an example of a light source used in the light-emitting module according to the embodiment. [Figure 3A] It is a schematic cross-sectional view showing an example of the light-emitting module according to the embodiment. [Figure 3B] It is a schematic cross-sectional view showing an example of the light-emitting module according to the embodiment. [Figure 3C] It is a schematic cross-sectional view showing an example of the light-emitting module according to the embodiment. [Figure 4] It is a schematic cross-sectional view showing an example of a planar light source according to the embodiment. [Figure 5]It is a schematic cross-sectional view showing an example of a planar light source according to an embodiment. [Figure 6] It is a schematic cross-sectional view showing an example of a planar light source according to an embodiment.

Mode for Carrying Out the Invention

[0008] While referring to the drawings, embodiments of the present invention will be described in detail. The following embodiments are illustrative, and the light-emitting module and the method for manufacturing the light-emitting module according to the embodiments of the present invention are not limited to the following embodiments. For example, the numerical values, shapes, materials, processes, the order of those processes, etc. shown in the following embodiments are merely examples, and various modifications are possible as long as there is no technical contradiction. Each of the embodiments described below can be combined in various ways as long as there is no technical contradiction.

[0009] The dimensions, shapes, etc. of the components shown in the drawings may be exaggerated for ease of understanding, and may not reflect the actual dimensions, shapes, and the size relationships between the components. Also, in order to avoid making the drawings overly complicated, a schematic diagram in which the illustration of some elements is omitted may be used, or an end view showing only the cut surface as a cross-sectional view may be used.

[0010] [Light-Emitting Module] The light-emitting module 100 includes a substrate 10 and a light source 20. (Embodiment 1) FIGS. 1A to 1D show the light-emitting module 100 (100A) according to the present embodiment. The light-emitting module 100A includes a substrate 10 and a light source 20.

[0011] The substrate 10 comprises an insulating base material 11 and wiring 12. The base material 11 comprises a first surface 111 and a second surface 112 opposite to the first surface 111. In the example shown in Figure 1D, the first surface 111 is the lower surface of the base material 11, and the second surface 112 is the upper surface of the base material 11. The first surface 111 may be referred to as the bottom surface, and the second surface 112 as the top surface. The second surface 112 is the light-emitting surface side of the light-emitting module 100A. Furthermore, the base material 11 has a hole 113 that penetrates from the first surface 111 to the second surface 112.

[0012] The first wiring 121 of the wiring 12 is positioned on the first surface 111 of the base material 11. The first wiring 121 is also positioned in a location that overlaps with the hole 113 when viewed from above. In other words, the first wiring 121 is positioned within the hole 113 and is exposed from the base material 11.

[0013] The light source 20 is electrically connected to the first wiring 121 in the hole 113. The light source 20 is positioned on the first wiring 121 located on the first surface 111 opposite to the second surface 112, which is the emission surface side. The light source 20 includes a light-emitting element 21. The light source 20 can be a light-emitting device including the light-emitting element 21 and a sealing member, as will be described later. The light-emitting element 21 comprises a semiconductor laminate 22 and a pair of positive and negative electrodes 23. The semiconductor laminate 22 comprises an upper surface 22U and a lower surface 22D opposite to the upper surface 22U. The electrodes 23 are positioned on the lower surface 22D of the semiconductor laminate 22.

[0014] By having a hole 113 in the substrate 11, which is the base material of the substrate 10, and arranging the light source 20 within the hole 113, the light-emitting module can be made thinner compared to when the light source is arranged on a substrate without a hole.

[0015] Furthermore, within the hole 113, the lower surface 22D of the semiconductor laminate 22 is located below the second surface 112 of the substrate 11. This allows for a thinner light-emitting module.

[0016] The height difference between the second surface 112 of the substrate 11 and the lower surface 22D of the semiconductor laminate 22 can be, for example, 5 μm to 40 μm. Such a height difference can be adjusted by the thickness of the electrodes 23 of the light source 20. Alternatively, as shown in Figure 1D, if a conductive bonding member 40 such as solder is used to join the light source 20 and the first wiring 121, the above-mentioned height difference can be achieved by adjusting the thickness of the conductive bonding member 40.

[0017] The upper surface 22U of the semiconductor laminate 22 is preferably located above the second surface 112 of the substrate 11. This makes it easier for the light emitted from the light source 20 to spread laterally.

[0018] The following provides a detailed explanation of each component that makes up the light-emitting module.

[0019] (substrate) The substrate 10 is a component that supports the light source 20. The substrate 10 comprises an insulating base material 11 and conductive wiring 12. The base material 11 comprises a first surface 111 and a second surface 112 opposite to the first surface 111. Furthermore, the base material 11 comprises a hole 113 that penetrates from the first surface 111 to the second surface 112. The substrate 10 comprises first wiring 121 as wiring 12, which is arranged at least on the side of the first surface 111. Since it is electrically connected to the positive or negative electrode of the light source 20, the hole 113 comprises at least two or more first wirings 121. The base material 11 is not present in the region where the light source 20 is placed.

[0020] The substrate 10 may also include a second wiring 122 arranged on the second surface 112 side as wiring 12. Furthermore, the substrate 10 may include conductive vias 13 that electrically connect the first wiring 121 and the second wiring 122. The substrate 10 may be a rigid substrate or a flexible substrate. The substrate 10 can be purchased and prepared. Alternatively, a substrate 10 can be prepared by preparing a base material, first wiring, second wiring, etc., and then partially processing it.

[0021] For example, ceramics or resin can be used as the base material 11. Specific materials include silicon nitride and aluminum oxide as ceramics. Examples of resins include phenol, epoxy, polyimide, BT resin, polyphthalamide (PPA), polyethylene terephthalate (PET), unsaturated polyester, and composite materials such as glass epoxy. These can be used as a single layer or in multiple layers. When multiple layers are used, they can be laminated with an adhesive in between.

[0022] The thickness of the substrate 11 can be, for example, 5 μm to 40 μm. The second surface 112 of the substrate 11 is located above the lower surface 22D of the semiconductor laminate 22. In this case, the entire second surface 112 of the substrate 11 can be located above the lower surface 22D of the semiconductor laminate 22. Alternatively, at least a portion of the second surface 112 of the substrate 11 can be located above the lower surface 22D of the semiconductor laminate 22. For example, the upper end of the substrate 11 closest to the light source 20, that is, the side surface defining the hole 113 in which the light source 20 is placed, can be located below the lower surface 22D of the semiconductor laminate 22.

[0023] The hole 113 in the substrate 11 is the portion where the light source 20 is placed. The hole 113 penetrates from the first surface 111 to the second surface 112 of the substrate 11. The side surface defining the hole 113 can be a surface perpendicular to the first surface 111 or the second surface 112, or an inclined surface. The shape of the opening of the hole 113 can be, for example, circular, square, etc. The size of the opening of the hole 113 is at least larger than the size of the light source 20. For example, in a top view, the maximum length of the opening of the hole 113 can be 5% to 30% of the maximum length of the light source 20.

[0024] Examples of wiring 12 include those made by laminating metal plates or metal foils, those made by electroplating or electroless plating the base material 11, or those made by placing and curing a conductive paste. Specific materials for wiring 12 include materials mainly composed of metals such as copper, silver, and aluminum.

[0025] In particular, the first wiring 121 supporting the light source 20 is preferably a metal plate (thickness 0.1 mm or more) or a metal foil (thickness less than 0.1 mm). Examples of metal plates include copper plates, gold plates, and aluminum plates. Examples of metal foils include copper foil, gold foil, and aluminum foil. The thickness of the metal plate can be, for example, 0.25 mm to 0.5 mm, and the thickness of the metal foil can be, for example, 12 μm to 35 μm.

[0026] The first wiring 121 is positioned within the hole 113 of the base material 11. Furthermore, a pair of first wirings 121 are arranged within the hole 113 so that they can be connected to at least one pair of electrodes provided by the light source 20. Nothing may be placed between the pair of first wirings 121, or an insulating first member 60, described later, may be placed between them. The base material 11 and the first wiring 121 may also be bonded together via an adhesive. Examples of adhesives include silicone, epoxy, acrylic, and polyimide. The adhesive may be provided as part of the base material 11 beforehand, or it may be prepared as a separate component from the base material 11.

[0027] Furthermore, it is preferable to use a second wiring 122 that has been cured after being placed on the second surface 112 side of the base material 11. The thickness of the second wiring 122 can be, for example, 10 μm to 30 μm.

[0028] The second wiring 122 can be formed, for example, by placing a conductive paste such as copper paste or silver paste and then curing it. The second wiring 122 only needs to be located on the second surface 112 side. That is, the second wiring 122 may be placed on the second surface 112 of the substrate 11, or it may be placed in a recess located on the second surface 112, as shown in Figure 1D. In particular, by placing the second wiring 122 in a recess located on the second surface 112, it is possible to suppress an increase in the thickness of the substrate 10. Alternatively, the second wiring 122 may be placed on a component located on the second surface 112 of the substrate 11.

[0029] The second wiring 122 may be placed on the second surface 112 side of the base material 11, or it may be placed in a through-hole that penetrates from the second surface 112 to the first surface 111 of the base material 11. This allows a portion of the second wiring 122 to be used as a conductive via 13. The through-hole is a through-hole located at a distance from the hole 113 where the light source 20 is placed.

[0030] Furthermore, the conductive via 13 that electrically connects the first wiring 121 and the second wiring 122 may be arranged separately from the first wiring 121 or the second wiring 122. Examples of such conductive vias 13 include copper and silver. The conductive via 13 can be formed, for example, by placing a conductive paste such as copper paste or silver paste inside a through-hole in a substrate 11 and allowing it to harden.

[0031] As shown in Figure 1C, the conductive via 13 is positioned away from the light source 20, where the first wiring 121 and the second wiring 122 overlap in a top view. The number of conductive vias 13 can be selected according to the width of the first wiring 121 and the second wiring 122. For example, in the example shown in Figure 1B, two conductive vias 13 are placed in the region close to the light source 20. In addition, six conductive vias 13 are placed in the region sandwiched between the regions connected by these two conductive vias 13. This is a region where one second wiring 122 overlaps the part where three first wirings 121 converge, and by placing multiple conductive vias 13, it is possible to make it easier for more current to flow. Furthermore, if a problem occurs such as a conductive via 13 being disconnected due to some factor, a conductive path can be secured by providing multiple conductive vias 13, and power supply can be maintained.

[0032] (light source) The light source 20 includes a light-emitting element 21. The light-emitting element 21 includes a semiconductor laminate 22 and a pair of positive and negative electrodes 23. As shown in Figure 2A, the semiconductor laminate 22 has an upper surface 22U and a lower surface 22D opposite to the upper surface 22U. The electrodes 23 are arranged on the lower surface 22D of the semiconductor laminate 22.

[0033] The light sources 20 are arranged in two dimensions when viewed from above. Preferably, the multiple through holes are arranged in two dimensions along two orthogonal directions, namely the x-direction (horizontal direction) and the y-direction (vertical direction). For example, as shown in Figure 1A, the arrangement pitch of the light sources 20 in the vertical and horizontal directions may be the same or different. Also, the two directions of arrangement do not have to be orthogonal.

[0034] The light source 20 can be a single light-emitting element 21, as shown in Figure 2A, as shown in light source 20A. Alternatively, the light source 20 can be a light-emitting device 20B to 20G comprising a light-emitting element 21 and a sealing member 24 that seals the light-emitting element 21, as shown in Figures 2B to 2G. Furthermore, the light source 20 can be a light-emitting device 20G comprising a light-emitting element 21, a sealing member 24, a package 25 on which these can be arranged, and a lens 26 placed on the package 25, as shown in Figure 2G.

[0035] The light-emitting element 21 can utilize known semiconductor light-emitting elements such as light-emitting diodes. The composition, emission peak wavelength, size, and number of elements of the semiconductor laminate 22 of the light-emitting element 21 can be appropriately selected according to the purpose. The light-emitting element 21 can be selected to emit light of any wavelength from ultraviolet to visible light. For example, as a light-emitting element that emits ultraviolet, blue, and green light, the semiconductor laminate 22 can be made of nitride semiconductor (In x Al y Ga 1-x-y A light-emitting element using N (0 ≤ X, 0 ≤ Y, X + Y ≤ 1) can be used. Examples of light-emitting elements that emit red light include GaAs, GaP, and InP. The emission wavelength can be selected in various ways depending on the material of the semiconductor laminate 22 and its mixed crystallinity. The shape of the semiconductor laminate 22 can be a quadrilateral such as a square or rectangle, or a polygon such as a triangle or hexagon when viewed from above. The size of the semiconductor laminate 22 when viewed from above can be, for example, a side length of 500 μm to 3000 μm. The thickness of the semiconductor laminate 22 can be, for example, 25 μm to 40 μm. For the electrodes 23 of the light-emitting element 21, for example, copper, gold, nickel, etc. can be used. The thickness of the electrodes 23 can be, for example, 10 μm to 50 μm.

[0036] The sealing member 24 seals the light-emitting element 21 such that at least the electrodes 23 of the light-emitting element 21 are exposed. The sealing member 24 may include resin or glass. Examples of resins include epoxy, silicone, polyethylene terephthalate, and the like.

[0037] The sealing member 24 can be a light-transmitting sealing member (first sealing member 241) only, as shown in Figure 2B. The first sealing member 241 only needs to cover at least one surface of the semiconductor laminate 22. In the example shown in Figure 2B, the first sealing member 241 covers the top surface 22U and the side surface of the semiconductor laminate 22, while the bottom surface 22D is exposed. The first sealing member 241 may cover the entire surface of the semiconductor laminate 22.

[0038] The sealing member 24 may include a light-transmitting sealing member (first sealing member) and a light-reflective sealing member (second sealing member). For example, in the light source 20C shown in Figure 2C, the top and side surfaces of the semiconductor laminate 22 are covered with the first sealing member 241, and the bottom surface of the semiconductor laminate 22 is covered with the second sealing member 242. In addition, the light source 20D shown in Figure 2D includes, in addition to the light source 20C, a second sealing member 242 on top of the first sealing member 241. In the light source 20E shown in Figure 2E, the side and bottom surfaces of the semiconductor laminate 22 are covered with the second sealing member 242, and the top surface is covered with the first sealing member 241. The first sealing member 241 is exposed from the second sealing member 242 on the side surface of the light source 20E. In the light source 20F shown in Figure 2F, the side surface of the first sealing member 241 is covered with the second sealing member 242.

[0039] The first sealing member 241 is translucent, allowing at least light from the light-emitting element 21 to pass through, transmitting 60% or more of the light emitted from the light-emitting element 21, preferably 90% or more. As the resin material, thermosetting resin materials such as epoxy and silicone can be used. The first sealing member 241 can be made solely from these translucent resin materials. Alternatively, a translucent resin material can be used as the base material, and a phosphor can be included as a wavelength conversion material.

[0040] Examples of phosphors include yttrium aluminum garnet phosphors (e.g., (Y,Gd)3(Al,Ga)5O 12 Ce), lutetium-aluminum-garnet phosphors (e.g., Lu3(Al,Ga)5O 12:(Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb3(Al,Ga)5O 12 :(Ce), CCA-based phosphor (e.g., Ca 10 (PO4)6Cl2:Eu), SAE-based phosphor (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate-based phosphor (e.g., Ca8MgSi4O 16 Cl2:Eu), silicate-based phosphor (e.g., (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon-based phosphor (e.g., (Si,Al)3(O,N)4:Eu) or α-sialon-based phosphor (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu) and other oxynitride-based phosphors, LSN-based phosphor (e.g., (La,Y)3Si6N 11 :Ce), BSESN-based phosphor (e.g., (Ba,Sr)2Si5N8:Eu), SLA-based phosphor (e.g., SrLiAl3N4:Eu), CASN-based phosphor (e.g., CaAlSiN3:Eu) or SCASN-based phosphor (e.g., (Sr,Ca)AlSiN3:Eu) and other nitride-based phosphors, KSF-based phosphor (e.g., K2SiF6:Mn), KSAF-based phosphor (e.g., K2(Si 1-x Al x )F 6-x :Mn Here, x satisfies 0 < x < 1.) or MGF-based phosphor (e.g., 3.5MgO·0.5MgF2·GeO2:Mn) and other fluoride-based phosphors, quantum dots having a perovskite structure (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3 Here, FA and MA represent formamidinium and methylammonium, respectively.), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or quantum dots having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se)2) can be used.

[0041] These phosphors can be of one or more types. The first sealing member 241 may contain a light-diffusing material. Examples of light-diffusing materials include fine particles of titanium dioxide, silicon dioxide, aluminum oxide, zinc oxide, etc.

[0042] The second sealing member 242 is light-reflective. For example, the second sealing member 242 has a reflectance of 60% or more, preferably 90% or more, to light emitted from the light-emitting element 21. The material of the second sealing member 242 can be, for example, metal, a white resin member, a white inorganic member, a DBR film, etc. A white resin member is particularly preferred for the material of the second sealing member 242. Examples of white resin members include epoxy, silicone, polyethylene terephthalate, etc., as the base material, and resin members containing titanium oxide, aluminum oxide, silicon oxide, zinc oxide, gas, etc., as light-reflective substances on these base materials.

[0043] If the sealing member 24 includes a first sealing member 241 and a second sealing member 242, a third sealing member may be provided between the first sealing member 241 and / or the second sealing member 242 and the light-emitting element 21. The third sealing member can function, for example, as a joining member that joins the light-emitting element 21 with the first sealing member 241 and / or the second sealing member 242. Such a third sealing member is preferably made of a translucent resin material such as epoxy or silicone.

[0044] The light source 20G shown in Figure 2G comprises a package 25 and a lens 26. The package 25 includes a base 251 and a conductive member 252. Examples of the base 251 include resin materials such as silicone, epoxy, and nylon, ceramic materials such as aluminum nitride and aluminum oxide, and glass. Examples of the conductive member 252 include metal plates such as copper and iron, and those with plating on their surfaces.

[0045] (Conductive bonding member) The conductive bonding member 40 is a member that electrically connects the light source 20 and the first wiring 121, as shown in Figure 1D, for example. Examples of conductive bonding members include eutectic materials such as AuSn, silver paste, and copper paste. The conductive bonding member 40 is positioned between each of the positive and negative electrodes 23 of the light source 20 and the upper surface of the first wiring 121. Alternatively, the conductive bonding member 40 may be positioned on the side surface and / or the lower surface of the first wiring 121.

[0046] The light-emitting module 100 (100A) may further include components such as a light-reflective member 30, an insulating member 50, and a first member 60.

[0047] (Light-reflective material) The light-reflective member 30 is placed on the second surface 112 of the substrate 11. If the substrate 10 has a second wiring 122 on the second surface 112 side of the substrate 11, it is preferable that the light-reflective member 30 covers the second wiring 122. Alternatively, the light-reflective member 30 may be placed inside the holes 113 of the substrate 11. The light-reflective member 30 has a reflectivity of 70% to 90% with respect to light emitted from the light source 20, preferably 80% to 85%. The material of the light-reflective member 30 can be, for example, a white resin material. Examples of white resin materials include those containing a light-reflective substance in the base material. Examples of light-reflective substances include resin materials containing titanium oxide, aluminum oxide, silicon oxide, zinc oxide, gas, etc. As the base material, translucent thermosetting resin materials such as epoxy, silicone, and polyethylene terephthalate can be used.

[0048] (Insulating material) The insulating member 50 is an insulating member that primarily covers the first wiring 121, which is arranged on the first surface 111 of the base material 11. The insulating member 50 can also cover the first surface 111 of the base material 11 where the first wiring 121 is not present. Examples of insulating members 50 include insulating sheets made of epoxy, silicone, polyimide, polyester, etc.

[0049] (First component) As shown in Figure 1D, the first member 60 is an insulating member positioned between two spaced-apart first wirings 121 within the hole 113 of the base material 11. The first member 60 can be made of the same material as the insulating member 50, or the same material as the light-reflective member 30. Alternatively, the first member 60 may be a part of the insulating member 50, or a part of the light-reflective member 30. The thickness of the first member 60 positioned between the first wirings 121 can be, for example, 100% to 110% of the thickness of the first wirings 121.

[0050] <Embodiment 2> Figure 3A shows an example of a light-emitting module 100B according to this embodiment. The light-emitting module 100B comprises a substrate 10, a light source 20, and a light-reflective member 30.

[0051] In this embodiment, the light-reflective member 30 covers the first wiring 121 which is placed in the hole 113 of the base material 11. In the example shown in Figure 3A, the lower surface 22D of the semiconductor laminate 22 is located below the second surface 112 of the base material 11. However, this is not limited to this, and for example, as shown in Figure 3B, the lower surface of the semiconductor laminate 22 may be located on the same plane as the second surface 112 of the base material 11. Alternatively, the lower surface 22D of the optical semiconductor laminate 22 may be located above the second surface 112 of the base material 11.

[0052] In this embodiment as well, the substrate 11, which is the base material of the substrate 10, has holes 113, and the light source 20 is placed in the holes 113. This makes it possible to make the light-emitting module 100 thinner compared to the case where the light source is placed on a substrate that does not have holes.

[0053] Furthermore, by covering the first wiring 121 in which the light-reflective member 30 is placed within the hole 113, a thinner light-emitting module 100 can be made while suppressing a decrease in light extraction efficiency.

[0054] The following details the main differences from Embodiment 1.

[0055] (Light-reflective material) The light-reflective member 30 covers at least a portion of the first wiring 121 that is positioned within the hole 113 of the base material 11. For example, the light-reflective member 30 shown in Figure 3A covers the entire upper surface of both of the pair of first wiring 121 positioned within the hole 113. The light-reflective member 30 can also be positioned to cover at least a portion of the side surface of the base material 11 that defines the hole 113. For example, in the example shown in Figure 3A, the light-reflective member 30 covers a portion of the side surface of the base material 11 that defines the hole 113. In other words, a portion of the side surface of the base material 11 that defines the hole 113 is exposed from the light-reflective member 30. The light-reflective member 30 can also cover the entire side surface of the base material 11 that defines the hole 113, for example, as shown in Figures 3B and 3C. In the example shown in Figure 3B, the lower surface 22D of the semiconductor laminate 22 of the light source 20 is at approximately the same height as the second surface 112 of the substrate 11, and the light-reflective member 30 is positioned to fill the space within the hole 113. Also, in the example shown in Figure 3B, the length of the electrode 23 is longer than that of the electrode 23 shown in Figure 3B. By increasing the length of the electrode 23 in this way, the distance between the lower surface 22D of the semiconductor laminate 22 and the first wiring 121 can be increased, making it easier to position the light-reflective member 30 below the semiconductor laminate 22. In such a case, it is easy to position the light-reflective member 30 between the first wiring 121 as shown in Figure 3B.

[0056] The light-reflecting member 30 can be positioned in contact with the lower surface of the light source 20, or at a distance from it. Furthermore, the light-reflecting member 30 can be positioned in contact with the side surface of the light source 20, or at a distance from the side surface of the light source 20.

[0057] The light-reflective member 30 can be positioned to cover the second surface 112 of the base material 11 and / or the second wiring 122 on the second surface 112. Preferably, the light-reflective member 30 is positioned to cover the second surface 112 and the second wiring 122 of the base material 11, and to continuously cover the inside of the hole 113, as shown in Figure 3C. Preferably, the height of the upper surface of the light-reflective member 30 positioned on the second surface 112 or the second wiring 122 of the base material 11 is lower than the height of the upper surface of the light source 20. This makes it easier to illuminate the second surface 112 with light emitted from the light source 20.

[0058] In the substrate 10 supporting the light source 20, the base material 11 has holes 113, and the light source 20 is placed within these holes 113. This allows the light-emitting module 100 to be made thinner compared to when the light source is placed on a substrate without holes. Furthermore, by placing the light-reflective member 30 within the holes 113, light from the light source 20 can be reflected efficiently. This improves the light extraction efficiency.

[0059] [Surface light source] The planar light source comprises a light-emitting module and an optical component. At least one of the following can be used as the optical component: a light guide member, a lens member, a reflector, etc.

[0060] <Embodiment 3> Figure 4 shows an example of a planar light source 200. Here, the light-emitting module 100D shown in Figure 3C is used as an example of the light-emitting module 100. The planar light source 200 includes a light guide member 210 as an optical element on the second surface 112 side of the light-emitting module 100. The light guide member 210 is plate-shaped or sheet-shaped, having a first main surface 211 and a second main surface 212 opposite to the first main surface 211, and includes a light source placement section 213 where the light source 20 of the light-emitting module 100 is placed. In the example shown in Figure 4, the light source placement section 213 is a through hole that penetrates from the first main surface 211 to the second main surface 212 of the light guide member 210. Alternatively, the light source placement section 213 may be a recess that opens only on the first main surface 211 of the light guide member 210.

[0061] The planar light source 200 may include a light-transmitting member 220 placed within the light source arrangement section 213. Furthermore, the planar light source 200 may include a light adjustment member 230 on top of the light source arrangement section 213.

[0062] By positioning the light source 20 in the holes 113 of the substrate 11 of the substrate 10, the height of the light-emitting module 100 can be reduced compared to when it is positioned in a substrate without holes. Therefore, by using such a light-emitting module 100, the planar light source can be made thinner. Furthermore, by positioning the lower surface of the semiconductor laminate 22 of the light source 20 below the second surface 112 of the substrate 11, the thickness of the light guide member can be reduced, further thinning the planar light source. In addition, by providing a light-reflective member 30 that covers the first wiring 121 in the holes 113, a thin planar light source with high light extraction efficiency can be achieved.

[0063] (Optical components / Light guide components) A light guide member is a translucent member that spreads light from a light source in a planar manner. When the top view shape of the light guide member is rectangular, the size when viewed from above can be, for example, about 1 cm to 200 cm on each side. The thickness of the light guide member can be about 0.1 mm to 5 mm, with 0.5 mm to 3 mm being preferable. Here, "thickness" refers to the thickness assuming that there are no recesses, protrusions, or grooves on the first or second main surface, for example. The top view shape of the light guide member can be a quadrilateral such as a square or rectangle. Alternatively, it can be a polygon such as a triangle, hexagon, or octagon, or a circle or ellipse. Furthermore, it can be a combination of these shapes, or a shape with some parts rounded or some parts missing.

[0064] As the material for the light guide member, thermoplastic resins such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, or polyester, or thermosetting resins such as epoxy or silicone, or optically transparent materials such as glass can be used. Thermoplastic resin materials are particularly preferred because they can be efficiently manufactured by injection molding. Among these, polycarbonate is preferred because it is highly transparent and inexpensive. Furthermore, the cost of the light-emitting module can be reduced by using inexpensive materials such as polyethylene terephthalate. In addition, heat resistance can be improved compared to polycarbonate.

[0065] The light guide member can have a single layer or a structure in which multiple translucent layers are laminated. When the light guide member has multiple translucent layers, the layers can be bonded together using an adhesive. Furthermore, when multiple translucent layers are laminated, some or all of the layers can have through holes or recesses to create an air layer inside the light guide member. This makes it easier to diffuse light, resulting in a light-emitting module with reduced brightness unevenness.

[0066] The opening of the light source arrangement section 213 can be circular or elliptical when viewed from above. Alternatively, it can be a quadrilateral such as a square, rhombus, or rectangle. Furthermore, it can be a polygon such as a triangle, hexagon, or octagon.

[0067] <Embodiment 4> Figure 5 shows an example of a planar light source 300. Here, a light-emitting module 100 equipped with the light source 20C shown in Figure 2C is illustrated. The planar light source 300 is equipped with a light-transmitting lens member 310 as an optical element on the second surface 112 side of the substrate 11 of the light-emitting module 100.

[0068] The planar light source 300 may further be equipped with a light adjustment member on the upper surface of the lens member 310. The light adjustment member can be the same as the light adjustment member 230 shown in Figure 4.

[0069] By positioning the light source 20 in the holes 113 of the substrate 11 of the substrate 10, the height of the light-emitting module 100 can be reduced compared to when it is positioned in a substrate without holes. Therefore, by using such a light-emitting module 100, the planar light source can be made thinner. Furthermore, by positioning the lower surface of the semiconductor laminate 22 of the light source 20 below the second surface 112 of the substrate 11, the height of the lens member can be reduced, further thinning the planar light source. In addition, by providing a light-reflective member 30 that covers the first wiring 121 in the holes 113, a thin planar light source with high light extraction efficiency can be achieved.

[0070] (Lens component) A lens component is a component that controls the light distribution of light emitted from a light source. The lens component is a translucent component that covers the light source, and covers each of multiple light sources individually. In the example shown in Figure 5, a lens component 310 with a recessed upper surface is shown above the light source 20. Light emitted directly upward from the light source 20 can be reflected to the side by the recess. Air or a light-reflective component may be placed inside the recess. Examples of light-reflective components include white resin and metal.

[0071] The lens member 310 may have a convex upper surface. The lens member 310 can be prepared in advance by being molded and then placed to cover the light source 20. Alternatively, the lens member 310 can be placed by placing an uncured resin material to cover the light source 20 and then curing it. The shape of the lens member when viewed from above can be circular or elliptical. The size of the lens member can be, for example, a diameter of about 0.6 cm to 4 cm. The height of the lens member 310 can be, for example, about 0.2 mm to 2 mm. Here, "height" refers to the height from the second surface 112 of the base material 11 to the highest point of the lens member 310.

[0072] Lens components can be made from resin materials such as epoxy or silicone thermosetting resins, or optically transparent materials such as glass. The reflector can be made from a resin containing at least one reflective material from titanium oxide, aluminum oxide, and silicon oxide. Furthermore, the reflector may be molded using a resin that does not contain reflective material, and then a reflective material may be applied to its surface. Alternatively, a resin containing multiple fine gas particles may be used. Examples of resins used for the reflector include thermoplastic resins such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, polyethylene naphthalate, or polyester, or thermosetting resins such as epoxy resin or silicone resin. It is preferable that the reflector be set to have a reflectance of 70% or more to light emitted from a light source.

[0073] <Embodiment 5> Figure 6 shows an example of a planar light source 400. Here, a light-emitting module using the light source 20G shown in Figure 2G is shown as the light source 20. The planar light source 400 is equipped with a light-reflective reflector 410 as an optical element on the second surface 112 side of the substrate 11 of the light-emitting module 100.

[0074] By positioning the light source 20 in the holes 113 of the substrate 11 of the substrate 10, the height of the light-emitting module 100 can be reduced compared to when it is positioned in a substrate without holes. Therefore, by using such a light-emitting module 100, the planar light source can be made thinner. In addition, by positioning the lower surface of the semiconductor laminate 22 of the light source 20 below the second surface 112 of the substrate 11, the height of the reflector can be reduced, further thinning the planar light source. Furthermore, by providing a light-reflective member 30 that covers the first wiring 121 in the holes 113, a thin planar light source with high light extraction efficiency can be achieved.

[0075] (Reflector) A reflector is a component that reflects light emitted from a light source in a desired direction. The reflector 410 shown in Figure 6 integrates a wall portion with an inclined surface on the side of the light source 20G and a flat portion placed on the second surface 112 of the base material 11. It is preferable that the wall portion is arranged to surround the light source 20G when viewed from above. It is also preferable that the top of the wall portion is located above the top surface of the light source 20G. This allows light from the light source 20 to be efficiently reflected upward. Alternatively, the reflector may consist only of a flat portion without a wall portion. By covering the base material 11 and the second wiring with the reflector, the light extraction efficiency can be improved. Furthermore, the light extraction efficiency can be improved by reflecting the reflected light from an optical sheet such as a prism sheet placed above the planar light source with the reflector.

[0076] The planar light source can include both a lens member 310 as shown in Figure 5 and a reflector 410 as shown in Figure 6. [Industrial applicability]

[0077] The light-emitting module described herein can be used, for example, as a backlight for a liquid crystal display device. [Explanation of symbols]

[0078] 100, 100A… Light-emitting module 10... Circuit board 11...Base material (111...first surface, 112...second surface, 113...hole) 12...Wiring (121...1st wiring, 122...2nd wiring) 13...Conductive via 20…Light source 21…Light-emitting element 22...Semiconductor laminate (22U...top surface, 22D...bottom surface) 23...Electrode 24... Sealing member (241... First sealing member, 242... Second sealing member) 25...Package (251...Base, 252...Conductive component) 26... Lens 30…Light-reflective material 40... Conductive bonding member 50…Insulating material 60...First component 200…Surface light source 210...Optical component (light guide component) (211...First main surface, 212...Second main surface, 213...Light source arrangement section) 220…Translucent member 230...Light adjustment component 300…Surface light source 310…Optical components (lens components) 400…Surface light source 410…Optical components (reflectors)

Claims

1. A substrate having a first surface and a second surface opposite to the first surface, and having a hole that penetrates from the first surface to the second surface, and a wiring including a first wiring disposed on the first surface side, wherein the first wiring is positioned so as to overlap with the hole when viewed from above, A semiconductor laminate having an upper surface and a lower surface opposite the upper surface, an electrode disposed on the lower surface, and a light source including a light-emitting element, Equipped with, A light-emitting module in which the light-emitting element is arranged in the hole such that the lower surface of the semiconductor laminate is located below the second surface, the upper surface of the semiconductor laminate is located above the second surface, and the upper surface of the light-reflective member covering the second surface is located below the upper surface of the light source.

2. The light-emitting module according to claim 1, wherein the height difference between the second surface and the lower surface of the semiconductor laminate is 5 μm to 40 μm.

3. A substrate having a first surface and a second surface opposite to the first surface, and having a hole that penetrates from the first surface to the second surface, and a wiring including a first wiring disposed on the first surface, wherein the first wiring is positioned so as to overlap the hole when viewed from above, A light source is placed on the first wiring within the hole and electrically connected to the first wiring, A light-reflective member covers the first wiring positioned in the hole and further covers the second surface, Equipped with, A light-emitting module in which the upper surface of the semiconductor laminate included in the light source is located above the second surface, and the upper surface of the light-reflective member is located below the upper surface of the light source.

4. The light-emitting module according to claim 3, wherein the light-reflective member covers at least a portion of the side surface of the substrate defining the hole.

5. The substrate has a second wiring on the second side, The light-emitting module according to claim 3, wherein the light-reflective member covers the second surface and the second wiring of the substrate and continuously covers the inside of the hole.

6. A planar light source comprising the light-emitting module according to any one of claims 1 to 5, and an optical member.

7. The planar light source according to claim 6, wherein the optical member is a light guide member.

8. The planar light source according to claim 6, wherein the optical member is a lens member.

9. The planar light source according to claim 6, wherein the optical member is a reflector.

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