Light source module and manufacturing method of light source module

Abstract

To provide a light source module and a manufacturing method of the light source module, in which an exhaust property of heat generated in a light emitting element can be enhanced, and the generation of a migration in the light emitting element is suppressed.SOLUTION: A light source module comprises: a substrate; a sub-mount arranged onto a main surface of the substrate; a plurality of light emitting elements arranged in a first direction onto a mounting surface of the sub-mount; and a metal sinter body that bonds the sub-mount and the plurality of light emitting elements. The metal sinter body is expanded to an outside of each light emitting element in view of a normal direction of the mounting surface of the sub-mount, and a height when using the mounting surface of the sub-mount as a reference is lower than that of a light emitting layer of a first light emitting element and a light emitting layer of a second light emitting element in a part positioned between the first light emitting element and the second light emitting element that are adjacent to each other in a first direction from the plurality of light emitting elements.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a light source module and a method for manufacturing the light source module. [Background technology]

[0002] Conventionally, light source modules equipped with light emitting elements such as LED elements and LD elements are required to have higher brightness depending on the application. For example, the following Patent Document 1 discloses a light source module in which multiple LED elements are arranged on a substrate to achieve high brightness. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-081832 A Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that LED and LD elements lose their luminous efficiency and shift their peak wavelength when the temperature of the element itself becomes high when lit. In addition, one of the challenges for high-brightness light source modules is to arrange them more densely and to realize materials and structures with better heat dissipation performance.

[0005] A typical light source module is fabricated by mounting a light emitting element on a substrate using a bonding material containing a metal material. In addition, as the bonding material used when mounting the light emitting element, a bonding material containing silver as a main material, more specifically, for example, a silver paste, is often adopted in consideration of heat dissipation properties and cost aspects.

[0006] However, in a light source device in which a light emitting element is mounted using silver paste, repeated application of a voltage to the light emitting element causes a phenomenon called migration near the electrode (anode) of the light emitting element (sometimes called "ion migration"). Specifically, migration here refers to the phenomenon in which silver contained in the silver paste comes into contact with moisture present around the LED element near the electrode, and when a voltage is applied there, silver or silver oxide precipitates.

[0007] In consideration of the above problems, the light source device of the present invention aims to provide a light source module that improves the ability to dissipate heat generated in light-emitting elements and suppresses the occurrence of migration in the light-emitting elements, and a method for manufacturing the light source module. [Means for solving the problem]

[0008] The light source module of the present invention comprises: A substrate; a submount disposed on a major surface of the substrate; A plurality of light emitting elements arranged in a first direction on a mounting surface of the submount; a gold sintered body that bonds the submount and the plurality of light emitting elements; The gold sintered body extends outside the light-emitting element when viewed from the normal direction of the mounting surface of the submount, and in a portion of the plurality of light-emitting elements located between a first light-emitting element and a second light-emitting element that are adjacent to each other in the first direction, the height, based on the mounting surface of the submount, is lower than both the light-emitting layer of the first light-emitting element and the light-emitting layer of the second light-emitting element.

[0009] The terms "first light-emitting element" and "second light-emitting element" herein are not used to refer to two specific light-emitting elements, but are intended to refer to any combination of light-emitting elements adjacent to each other in the first direction.

[0010] In addition, "spreading outside the light-emitting element" here refers not only to the case where it spreads over the entire periphery surrounding the light-emitting element, but also to the case where it spreads outside the light-emitting element in a portion of the periphery of the light-emitting element.

[0011] The submount is a structure that combines, for example, an aluminum nitride (AlN) substrate with a thick copper (Cu) film that has a relatively low thermal resistance. When mounting a semiconductor chip on the submount, the semiconductor chip is placed on a predetermined portion of the submount that has been coated with a paste agent containing gold particles, which is the material for the gold sintered body. The paste agent is then dried and heat-treated to sinter, and the gold sintered body that is formed bonds the submount and the light-emitting element.

[0012] The gold sintered body forms an electrical path between the substrate and the light-emitting element. Specifically, the gold sintered body electrically connects a conductive portion formed on the submount to at least one electrode of the light-emitting element when the submount and the light-emitting element are joined.

[0013] Gold (Au) exhibits a thermal resistivity almost equal to that of silver (Ag). In addition, gold (Au) has a smaller tendency to ionize than silver (Ag), and migration, which occurs when a silver sintered body is used, hardly occurs at all. For this reason, light source modules using gold sintered bodies have less migration than conventional ones, realizing a longer life and higher reliability.

[0014] In addition, the side of the light-emitting element often shows the side of the light-emitting layer that generates light when electricity is applied. Therefore, when the mounting surface of the submount is used as a reference, if the height of the gold sintered body, especially the part located between the elements, becomes higher than the light-emitting layer, the gold sintered body in that part may electrically short out the light-emitting layer of the light-emitting element. In addition, if the gold sintered body is formed to a height that exceeds the light-emitting layer and reaches the light-emitting surface, it may hinder the progress of light emitted from the light-emitting element, reducing the light-emitting efficiency.

[0015] Therefore, between the first and second light emitting elements, the height of the gold sintered body must be lower than the height of the light emitting layer of the first light emitting element and the height of the light emitting layer of the second light emitting element. Also, it is preferable that the height of the gold sintered body is lower than the height of each of the light emitting layers of the light emitting elements.

[0016] As a result, the light source module having the above configuration achieves high heat dissipation performance and suppresses migration. In addition, electrical shorts between the light emitting layers of the light emitting elements through the gold sintered body are avoided.

[0017] The light source module is The distance between the first light emitting element and the second light emitting element may be 10 μm to 100 μm.

[0018] If the first light emitting element and the second light emitting element are too close to each other, they may be electrically shorted to each other. Also, if the first light emitting element and the second light emitting element are too close to each other, it becomes difficult to control the height of the gold sintered body located between the first light emitting element and the second light emitting element.

[0019] Conversely, if the first light emitting element and the second light emitting element are too far apart, they will not be disposed closely together, and high brightness will not be achieved.

[0020] In view of the above, it is preferable that the distance between the first light emitting element and the second light emitting element is within the above range.

[0021] In the above light source module, The plurality of light emitting elements may have a side length of 50 μm to 2,000 μm when viewed in a direction perpendicular to the light emitting surface.

[0022] If the light emitting element is too small, the bonding strength will be low, making it difficult to achieve high reliability.

[0023] Conversely, if the light emitting element is too large, a large amount of the gold sintered body is pushed aside, causing a large protrusion on the side surface of the light emitting element, making the light emitting element more susceptible to short circuits.

[0024] In view of the above, it is preferable that the length of one side of the light emitting element when viewed in a direction perpendicular to the light emitting surface is within the above range.

[0025] The method for manufacturing a light source module of the present invention includes the steps of: A step (A) of preparing a substrate and a submount; (B) applying a paste containing gold particles onto a major surface of the submount by screen printing; (C) placing the submount, the main surface of which is coated with the paste, on the main surface of the substrate; (D) placing a light emitting element on the portion of the main surface of the submount on which the paste is applied; After carrying out step (D), the method further comprises step (E) of heating the paste to form a gold sintered body.

[0026] Screen printing can form a film with a relatively uniform thickness by adjusting the mesh opening size and thickness according to the diameter of the particles contained in the paste. Therefore, compared with pin transfer, screen printing makes it easier to form a relatively thin film of the paste on the mounting surface of the submount with a uniform thickness.

[0027] Therefore, according to the above manufacturing method, if the paste film thickness is uniform, the minimum amount of paste is applied, and the amount of paste pushed out when placing the light emitting elements is reduced, resulting in an effect that the light emitting elements can be arranged at a higher density. Furthermore, the light source module manufactured by the above method can precisely adjust the shape and thickness of the gold sintered body, thereby realizing a long life and high reliability of the light source module. Effect of the Invention

[0028] In view of the above problems, the present invention provides a light source module and a method for manufacturing the light source module that improves the ability to dissipate heat generated in a light-emitting element and suppresses the occurrence of migration in the light-emitting element. [Brief description of the drawings]

[0029] [Figure 1] 2 is a schematic diagram showing an embodiment of a light source module as a whole viewed in the X direction. [Diagram 2] 1 is a diagram showing the light source module with the cover member removed, viewed from the +Z side. [Diagram 3] 2 is an enlarged view of the periphery of the light-emitting element in FIG. 1. [Figure 4A] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. [Figure 4B] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. [Figure 4C] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. [Figure 4D] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. [Figure 4E] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. [Figure 4F] 1 is a schematic diagram showing a state of a light source module in the process of being manufactured. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The light source module and the manufacturing method of the light source module of the present invention will be described below with reference to the drawings. Note that the following drawings are all schematic illustrations, and the dimensional ratios and numbers in the drawings do not necessarily match the actual dimensional ratios and numbers.

[0031] [composition] First, the configuration of the light source module 1 of this embodiment will be described. Fig. 1 is a schematic diagram of an embodiment of the light source module 1 as a whole viewed in the X direction. Fig. 2 is a diagram of the light source module 1 with the cover member 2 removed viewed from the +Z side. Fig. 3 is an enlarged diagram of the periphery of the light emitting element in Fig. 1.

[0032] As shown in Figures 1 to 3, the light source module 1 in this embodiment comprises a cover member 2, a substrate 10, a submount 11, a gold sintered body 12, multiple insulating substrates (13, 13, 13), multiple light-emitting elements (20a, 20b, 20c, 20d), multiple first wire wirings (21, 21, 21, 21) extending from each of the light-emitting elements (20a, 20b, 20c, 20d), and multiple second wire wirings (22, 22) extending from the submount.

[0033] 1 and 2, a plane parallel to the mounting surface 11a of the submount 11 is defined as an XY plane, and a direction perpendicular to the XY plane is defined as a Z direction. Then, as shown in FIG. 2, the direction in which the second wire wiring 22 extends is defined as an X direction, and the direction in which the first wire wiring 21 extends is defined as a Y direction.

[0034] In the embodiment described below, as can be seen from Fig. 2, there is no particular distinction between the X direction and the Y direction with regard to the arrangement of the light-emitting elements (20a, 20b, 20c, 20d). Therefore, there is no essential difference between the case where the X direction corresponds to the first direction and the case where the Y direction corresponds to the first direction, but for convenience of explanation, the following description will be given assuming that the Y direction corresponds to the first direction.

[0035] In addition, when expressing a direction, if a distinction is made between positive and negative directions, a positive or negative sign is added, such as "+Z direction" and "-Z direction." When expressing a direction without distinguishing between positive and negative directions, it is simply written as "Z direction."

[0036] The cover member 2 includes a light exit window 2a for extracting the light emitted from the light emitting elements 20 to the outside of the light source module 1, and a support 2b placed on the insulating substrate 13 and supporting the light exit window 2a. The material for forming the light exit window 2a is appropriately selected according to the wavelength band of the light emitted from each of the light emitting elements (20a, 20b, 20c, 20d), and may be, for example, glass, resin, or the like.

[0037] The substrate 10 has high heat dissipation properties via one electrode of the light emitting elements (20a, 20b, 20c, 20d) and the submount 11. Examples of materials for the substrate 10 include copper (Cu), aluminum (Al), and alumina (Al2O3). The substrate 10 may be a substrate made of a single material, or a substrate in which layers made of multiple materials are laminated.

[0038] A heat sink for dissipating heat may be connected to the substrate 10, and a fin shape may be formed to enhance heat dissipation.

[0039] 3, the submount 11 is a substrate including a ceramic layer 11p made of aluminum nitride (AlN) and a thermally conductive layer 11q made of copper (Cu). The ceramic layer 11p is a layer for ensuring insulation between the substrate 10 and the light-emitting elements (20a, 20b, 20c, 20d). The thermally conductive layer 11q is a layer formed of a material having a lower thermal resistance than the ceramic layer 11p, for more efficiently dissipating heat generated by the light-emitting elements 20.

[0040] Furthermore, a conductive pattern (not shown) is formed on the surface of the submount 11, and the conductive pattern ensures electrical connection between the light emitting elements (20a, 20b, 20c, 20d) and the substrate 10.

[0041] The ceramic layer 11p may be made of a material other than aluminum nitride (AlN), such as silicon carbide (SiC).

[0042] The material constituting the thermal conduction layer 11q may be, for example, carbon (C) or the like in addition to copper (Cu).

[0043] The gold sintered body 12 is a sintered body formed by applying a paste agent containing gold particles onto the submount 11, placing the light emitting element 20 to be fixed thereon, and then drying and sintering the resulting product.

[0044] 2 and 3, the gold sintered body 12 fixes the light-emitting elements (20a, 20b, 20c, 20d) on the submount 11. Furthermore, the gold sintered body 12 electrically connects the electrode 20e formed on the -Z side of the light-emitting elements (20a, 20b, 20c, 20d) to a conductive pattern (not shown) on the submount 11. Note that, as shown in FIG. 2, the gold sintered body 12 does not need to extend over the entire periphery of the light-emitting elements (20a, 20b, 20c, 20d) when viewed from the +Z side, and may extend outside the light-emitting elements (20a, 20b, 20c, 20d) only in part.

[0045] The insulating substrate 13 is a substrate for ensuring insulation from the substrate 10. On the insulating substrate 13, a conductive pattern 13a is formed, which has a different potential from that of the thermally conductive layer 11q when power is supplied to the light-emitting elements (20a, 20b, 20c, 20d).

[0046] 2, the light-emitting elements (20a, 20b, 20c, 20d) are LED elements fixed so as to be arranged in the X direction and the Y direction on a gold sintered body 12 formed on a submount 11. In the description of this embodiment, since the Y direction corresponds to the first direction, the light-emitting elements 20a and 20c correspond to the first light-emitting element, and the light-emitting elements 20b and 20d correspond to the second light-emitting element.

[0047] The light emitting elements 20a and 20c, and the light emitting elements 20b and 20d, which are arranged in the X direction, are spaced apart by 50 μm in the X direction. The light emitting elements 20a and 20b, and the light emitting elements 20c and 20d, which are arranged in the Y direction, are spaced apart by 50 μm in the Y direction.

[0048] As described above, the distance between adjacent light-emitting elements is preferably within a range of 10 μm to 100 μm in order to realize a high-density arrangement of the light-emitting elements (20a, 20b, 20c, 20d) and to control the height of the gold sintered body 12. However, if the desired brightness is obtained or if there is little effect on controlling the height of the gold sintered body 12, the distance between adjacent light-emitting elements may be outside this range.

[0049] As shown in Fig. 3, the light-emitting elements (20a, 20b, 20c, 20d) have a part of a light-emitting layer 20p that emits light when power is supplied and is exposed on the outer surface. In order to prevent an electrical short circuit of the light-emitting layers 20p of the light-emitting elements (20a, 20b, 20c, 20d), the height h1 of the gold sintered body 12 from the mounting surface 11a of the submount 11 is configured to be lower than the height h2 of the light-emitting layers 20p of the light-emitting elements (20a, 20b, 20c, 20d).

[0050] 3, the height of the gold sintered body 12 located between the adjacent light-emitting elements (20a, 20b, 20c, 20d) in the X or Y direction is shown as being constant, but the height of the gold sintered body 12 may vary at that position. When the height of the gold sintered body 12 varies, the height h1 is the height of the highest point of the gold sintered body 12 located between the adjacent light-emitting elements (20a, 20b, 20c, 20d).

[0051] Furthermore, the light emitting elements (20a, 20b, 20c, 20d) in this embodiment are square elements with a side length of 350 μm when viewed in a direction perpendicular to the light emitting surface 20f, that is, in the Z direction.

[0052] The length of one side of the light-emitting elements (20a, 20b, 20c, 20d) when viewed from the Z direction is arbitrary. However, as described above, from the viewpoint of stably disposing the light-emitting elements (20a, 20b, 20c, 20d) on the mounting surface 11a of the submount 11 in a desired orientation, the length is preferably within a range of 50 μm to 2,000 μm.

[0053] In addition, in the X direction or Y direction, except for the regions between adjacently arranged light-emitting elements (20a, 20b, 20c, 20d), the height h1 of the gold sintered body 12 is arbitrary as long as the light-emitting layers 20p of the multiple light-emitting elements (20a, 20b, 20c, 20d) are not electrically shorted.

[0054] As shown in Figures 1 and 2, the first wire wiring 21 is a wire that connects an electrode (not shown) formed on the +Z side surface of each light-emitting element (20a, 20b, 20c, 20d) to a conductive pattern 13a formed on the insulating substrate 13.

[0055] 2, the second wire wiring 22 is a wire that connects the submount 11 and the conductive pattern 13a formed on the insulating substrate 13 arranged on the -X side of the submount 11. Although the first wire wiring 21 and the second wire wiring 22 are described separately, there is no need for them to be made of different materials, and they may be formed by wire bonding in the same manner.

[0056] As a result, the light source module 1 configured as described above achieves high heat dissipation performance and suppression of migration. In addition, electrical shorts through the gold sintered body 12 of the light emitting layer 20p of each light emitting element (20a, 20b, 20c, 20d) are avoided. In other words, a light source module 1 with improved reliability compared to conventional ones is realized.

[0057] [Manufacturing method] Next, a description will be given of a manufacturing method of the light source module 1. Figures 4A to 4F are schematic diagrams each showing a state of the light source module 1 during manufacturing.

[0058] First, as shown in FIG. 4A, a substrate 10 is prepared (step S1).

[0059] Furthermore, a submount 11 is prepared (step S2). Steps S1 and S2 correspond to the process (A).

[0060] As shown in Fig. 4B, a paste 40 containing gold particles is screen-printed on the main surface (mounting surface 11a) of the submount 11 using a mesh 30 and a squeegee 31 so as to form a desired pattern (step S3). Step S3 corresponds to process (B). Note that the screen printing method shown in Fig. 4B is merely an example.

[0061] As described above, in screen printing, the thickness of the film to be formed can be controlled according to the particle diameter of the paste 40 by adjusting the opening size and thickness of the mesh 30. In addition, the area to which the paste 40 is applied can be precisely controlled by adjusting the shape of the mesh 30. For this reason, screen printing makes it easier to spread the gold paste uniformly over the mounting surface of the submount than pin transfer.

[0062] In this embodiment, the particle size of the gold particles contained in the paste 40 is adjusted to 0.2 μm to 0.4 μm. In the screen printing in step S3, a mesh 30 is used in which the opening has a side length of 25 μm and a thickness of 50 μm.

[0063] The length of one side of the opening of mesh 30 and the thickness are arbitrary, but from the viewpoint of making it easier to control the thickness of paste 40 on the main surface (mounting surface 11a) of submount 11, it is preferable that the length of one side of the opening of mesh 30 is 100 to 200 times the particle diameter of the gold particles contained in paste 40, and the thickness of mesh 30 is 200 to 300 times the particle diameter of the gold particles contained in paste 40.

[0064] After step S3 is performed, the submount 11 on which the paste 40 is screen-printed is placed on the main surface 10a of the substrate 10 via a bonding material (step S4), as shown in Fig. 4C. Step S4 corresponds to process (C).

[0065] Before, after, or at the same time as step S4, as shown in FIG. 4D, insulating substrate 13 having conductive pattern 13a formed thereon is placed on main surface 10a of substrate 10 (step S5).

[0066] After steps S4 and S5 are performed, the light emitting elements (20a, 20b) are placed on the paste 40 (step S6), as shown in Fig. 4E. Step S6 corresponds to the process (D).

[0067] In step S6, the height of the light emitting surface 20f of each light emitting element (20a, 20b, 20c, 20d) from the mounting surface 11a of the submount 11 is adjusted to be uniform, and the inclination angle of the light emitting surface 20f with respect to the XY plane is adjusted to be within a predetermined range.

[0068] 3, the degree to which the light emitting elements (20a, 20b, 20c, 20d) are pressed into the paste 40 is adjusted so that the height h1 of the paste 40 (gold sintered body 12) is lower than the height h2 of the light emitting layer 20p. If the height h2 is too high, heat dissipation is poor, and if it is too low, short circuits are likely to occur, so the height h2 is preferably within the range of 50 μm to 100 μm.

[0069] In step S6, the light-emitting elements (20c, 20d) are also placed, but for convenience of illustration in FIG. 4E, the light-emitting elements (20c, 20d) are hidden by the light-emitting elements (20a, 20b) and are not shown.

[0070] After step S6, a drying process and a heating process at 200° C. for 1 hour are performed to volatilize the solvent contained in the paste 40 and sinter the gold particles, thereby forming a gold sintered body 12 (step S7). Step S7 corresponds to process (E).

[0071] After the gold sintered body 12 is formed in step S7, the light-emitting elements (20a, 20b, 20c, 20d) are connected to the conductive pattern 13a on the insulating substrate 13 by the first wire wiring 21 (step S8), as shown in FIG. 4F.

[0072] After step S8 is performed or simultaneously with step S8, as shown in FIG. 2, the submount 11 and the conductive pattern 13a of the insulating substrate 13 arranged on the -X side of the submount 11 are connected by a second wire wiring 22 (step S9).

[0073] After the steps up to step S9 are completed, a cover member 2 is placed as shown in FIG. 1, and the light source module 1 is completed.

[0074] [Another embodiment] Another embodiment will be described below.

[0075] <1> In the above-described embodiment, the configuration of the light source module 1 in which two light-emitting elements are arranged in each of the X direction and the Y direction has been described, but the number of light-emitting elements arranged in each direction may be three or more. In other words, for example, the number of light-emitting elements arranged in the X direction may be different from the number of light-emitting elements arranged in the Y direction, and the configuration may include only one light-emitting element in either the X direction or the Y direction.

[0076] For example, when three light-emitting elements are arranged in each of the X and Y directions, the gold sintered body 12 located on the -Z side of the central light-emitting element may be slightly thicker than the gold sintered body 12 located on the -Z side of the surrounding light-emitting elements. In other words, the light-emitting surface of the central light-emitting element may be slightly closer to the +Z side than the light-emitting surfaces of the surrounding light-emitting elements.

[0077] According to this configuration, the illuminance distribution of the light emitted from the light source module 1 and hitting a screen placed at a predetermined distance away becomes closer to a normal distribution. Such a characteristic has the effect of facilitating the design of a light source device in which the light source module 1 is mounted.

[0078] Furthermore, the above-mentioned gold sintered body 12 is formed across all of the light-emitting elements (20a, 20b, 20c, 20d), but it may also be formed across a group of light-emitting elements arranged in one direction, either the X direction or the Y direction, or it may be formed individually for each of the light-emitting elements (20a, 20b, 20c, 20d).

[0079] Even if the gold sintered body 12 is formed individually for each of the light emitting elements (20a, 20b, 20c, 20d), the paste 40 may swell around the light emitting elements when the light emitting elements are placed. In this case, it is preferable to adjust the height h1 of the gold sintered body 12 located between adjacent light emitting elements to be lower than the height h2 of the light emitting layer 20p of the light emitting element (20a, 20b, 20c, 20d).

[0080] <2> In the above-mentioned embodiment, the light emitting element is described on the assumption that a pair of electrodes of the light emitting element are provided on the +Z side and the -Z side. However, the light emitting element mounted on the light source module 1 may be a light emitting element also called a flip chip type in which a pair of electrodes are formed on the same side. That is, the light source module 1 may adopt either a junction-up type or a junction-down type light emitting element (20a, 20b, 20c, 20d). Although any of the light emitting elements (20a, 20b, 20c, 20d) may be any type, it is preferable that the thickness is within a range of 100 μm to 130 μm and the height from the bottom surface of the light emitting element (20a, 20b, 20c, 20d) to the light emitting layer 20p is within a range of 70 μm to 95 μm.

[0081] In addition, in the case of a light-emitting element in which a pair of electrodes are formed on the same surface side, conductive patterns which become different potentials when lit are formed on the submount 11, and wire wiring (21, 22) is connected from each conductive pattern to the corresponding conductive pattern 13a on the insulating substrate 13.

[0082] <3> In the above embodiment, the light-emitting element is described as an LED element, but the light-emitting element may be an LD element. When the light-emitting element is a surface-emitting LD element, the height h1 of the gold sintered body 12 from the mounting surface 11a of the submount 11 is configured to be lower than the height of the upper surface of the light-emitting element.

[0083] <4> The configuration of the light source module 1 and the manufacturing method of the light source module 1 described above are merely examples, and the present invention is not limited to the respective configurations shown in the drawings. [Explanation of symbols]

[0084] 1: Light source module 2: Cover material 2a: Light exit window 2b: Support 10: Substrate 10a: Main surface 11: Submount 11a: Placement surface 11p: Ceramic layer 11q: Thermally conductive layer 12: Gold sintered body 13: Insulating substrate 13a: Conductive pattern 20a, 20b, 20c, 20d: Light emitting element 20e : Electrode 20f: Light exit surface 20p: Light-emitting layer 21: First wire wiring 22: Second wire wiring 30: Mesh 31: Squeegee 40: Paste h1,h2 : height

Claims

1. A substrate; a submount disposed on a major surface of the substrate; A plurality of light emitting elements arranged in a first direction on a mounting surface of the submount; a gold sintered body that bonds the submount and the plurality of light emitting elements; The gold sintered body extends outside the light-emitting element when viewed from the normal direction of the mounting surface of the submount, and in a portion of the plurality of light-emitting elements located between a first light-emitting element and a second light-emitting element that are adjacent to each other in the first direction, the height, based on the mounting surface of the submount, is lower than both the light-emitting layer of the first light-emitting element and the light-emitting layer of the second light-emitting element.

2. 2. The light source module according to claim 1, wherein the distance between the first light emitting element and the second light emitting element is 10 μm to 100 μm.

3. 3. The light source module according to claim 1, wherein each of the plurality of light-emitting elements has a side length of 50 μm to 2,000 μm when viewed in a direction perpendicular to the light-emitting surface.

4. A step (A) of preparing a substrate and a submount; (B) applying a paste containing gold particles onto a main surface of the submount by screen printing; (C) placing the submount, the main surface of which is coated with the paste, on the main surface of the substrate; a step (D) of mounting a light emitting element on the portion of the main surface of the submount on which the paste is applied; A method for manufacturing a light source module, comprising the steps of: (E) heating the paste and forming a gold sintered body after carrying out the step (D).

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