Semiconductor light-emitting device and method for manufacturing semiconductor light-emitting device

Abstract

To improve radiation pattern characteristics of a laser beam.SOLUTION: A semiconductor light-emitting device 10 includes: a surface light-emitting laser element 30 including an element surface 31 formed with a plurality of light-emitting parts 33; a peripheral wall 41 which is provided on the element surface 31, and surrounds the plurality of light-emitting parts 33 when being viewed from a direction vertical to the element surface 31; and a diffusion layer 50 which is provided so as to cover the plurality of light-emitting parts 33 in a region surrounded by the peripheral wall 41, and includes a diffusion material 51.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to semiconductor light emitting devices and methods for manufacturing semiconductor light emitting devices. [Background technology]

[0002] A configuration is known in which a surface-emitting laser element such as a vertical cavity surface-emitting laser (VCSEL) is used as a light source for a semiconductor light-emitting device (see, for example, Patent Document 1). A semiconductor light-emitting device using a surface-emitting laser element is sometimes used as a light source for, for example, LiDAR (Light Detection and Ranging) or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-109724

[0004] [overview] In recent years, LiDAR has been required to have a high output power in order to realize long-distance measurement. Generally, a surface-emitting laser device is known to have a configuration including a plurality of light-emitting units for the purpose of achieving a high output power. In a surface-emitting laser device having a plurality of light-emitting units, there is a risk that the emitted laser light may have uneven brightness. Therefore, there is room for improvement in the radiation pattern characteristics of the laser light emitted from a semiconductor light-emitting device having a surface-emitting laser element including a plurality of light-emitting units.

[0005] A semiconductor light-emitting device according to one embodiment of the present disclosure includes a surface-emitting laser element including an element surface on which a plurality of light-emitting portions are formed, a peripheral wall provided on the element surface and surrounding the plurality of light-emitting portions when viewed from a direction perpendicular to the element surface, and a diffusion layer including a diffusing material and provided within an area surrounded by the peripheral wall so as to cover the plurality of light-emitting portions. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic perspective view of a semiconductor light emitting device according to one embodiment. [Diagram 2] FIG. 2 is a schematic plan view showing the internal structure of the semiconductor light emitting device of FIG. [Diagram 3] FIG. 3 is a schematic plan view of the semiconductor light emitting device of FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view of the semiconductor light emitting device taken along line F4-F4 in FIG. [Diagram 5] 5A to 5C are schematic cross-sectional views illustrating exemplary manufacturing steps for the semiconductor light emitting device of FIG. [Figure 6] FIG. 6 is a schematic cross-sectional view showing a manufacturing process subsequent to FIG. [Figure 7] FIG. 7 is a schematic cross-sectional view showing a manufacturing process subsequent to FIG. [Figure 8] FIG. 8 is a schematic cross-sectional view of a semiconductor light emitting device according to a modified example.

[0007] [Detailed Description] Hereinafter, an embodiment of a semiconductor light emitting device according to the present disclosure will be described with reference to the accompanying drawings. Note that, for simplicity and clarity of description, the components shown in the drawings are not necessarily drawn to scale. Also, hatching lines may be omitted in cross-sectional views to facilitate understanding. The accompanying drawings are merely illustrative of embodiments of the present disclosure and should not be considered as limiting the present disclosure.

[0008] The following detailed description includes devices, systems, and methods embodying exemplary embodiments of the present disclosure. This detailed description is merely illustrative in nature and is not intended to limit the embodiments of the present disclosure or the application and uses of such embodiments.

[0009] <Embodiment> A semiconductor light emitting device 10 according to one embodiment will be described with reference to FIGS. FIG. 1 shows a schematic perspective structure of the semiconductor light emitting device 10. In FIG. 1, a cover member 40 and a diffusion layer 50, which will be described later, are indicated by two-dot chain lines. FIG. 2 shows a schematic planar structure showing the inside of the semiconductor light emitting device 10. In FIG. 2, the cover member 40 and the diffusion layer 50, which will be described later, are omitted in order to illustrate the internal structure of the semiconductor light emitting device 10. FIG. 3 shows a schematic planar structure of the semiconductor light emitting device 10 in FIG. 1. FIG. 4 shows a schematic cross-sectional structure of the semiconductor light emitting device 10 cut along line F4-F4 in FIG. 3. In addition, the term "planar view" used in the present disclosure refers to viewing the semiconductor light emitting device 10 in the Z direction of the mutually orthogonal XYZ axes shown in FIG. 1.

[0010] As shown in FIG. 1, the semiconductor light emitting device 10 includes a substrate 20 and a surface emitting laser element 30 disposed on the substrate 20. The substrate 20 is formed in a rectangular shape with the X direction being the longitudinal direction and the Y direction being the lateral direction in a plan view. The substrate 20 has a substrate front surface 21 and a substrate back surface 22 opposite the substrate front surface 21 in the Z direction. The substrate 20 has first to fourth substrate side surfaces 23 to 26 connecting the substrate front surface 21 and the substrate back surface 22. The first substrate side surface 23 and the second substrate side surface 24 constitute both end surfaces of the substrate 20 in the X direction, and the third substrate side surface 25 and the fourth substrate side surface 26 constitute both end surfaces of the substrate 20 in the Y direction. The shape of the substrate 20 in a plan view can be changed arbitrarily.

[0011] The substrate 20 is formed of, for example, an insulating material. The insulating material may be formed of, for example, a material containing epoxy resin. As an example, the substrate 20 may be formed of glass epoxy resin. The insulating material may also be formed of, for example, a material containing ceramic. Examples of materials containing ceramic include aluminum nitride (AlN) and alumina (Al2O3). When the substrate 20 is formed of a material containing ceramic, the heat dissipation performance of the substrate 20 is improved, and therefore the temperature of the semiconductor light emitting device 10 can be prevented from becoming excessively high.

[0012] The surface-emitting laser element 30 is a laser diode that emits laser light in a predetermined wavelength band, and functions as a light source for the semiconductor light-emitting device 10. For example, a vertical-cavity surface-emitting laser (VCSEL) is used as the surface-emitting laser element 30. This laser light may be visible light, or may be laser light having a longer wavelength than visible light, such as ultraviolet light. The surface-emitting laser element 30 is supported by the substrate 20.

[0013] 1 and 2, the surface-emitting laser element 30 is formed in a rectangular plate shape with the thickness direction being in the Z direction. The shape of the surface-emitting laser element 30 in plan view is a rectangle with the longitudinal direction being in the X direction and the lateral direction being in the Y direction. Note that the shape of the surface-emitting laser element 30 in plan view can be changed arbitrarily.

[0014] 4, the surface-emitting laser element 30 includes an element front surface 31 and an element back surface 32 that face opposite to each other in the Z direction. Furthermore, as shown in Fig. 1, the surface-emitting laser element 30 includes four element side surfaces 37 that connect the element front surface 31 and the element back surface 32. The element front surface 31 includes, for example, a flat surface perpendicular to the Z direction.

[0015] As shown in FIG. 2, the surface-emitting laser element 30 has a plurality of light-emitting sections 33 formed on an element surface 31. Each of the plurality of light-emitting sections 33 is configured to emit laser light in the Z direction. The plurality of light-emitting sections 33 are formed in an intermediate region between both ends of the surface-emitting laser element 30 in the X direction. The plurality of light-emitting sections 33 are arranged apart from each other in both the X direction and the Y direction. The plurality of light-emitting sections 33 are arranged in a substantially circular shape. Therefore, the surface-emitting laser element 30 includes a light-emitting region 38 in which the plurality of light-emitting sections 33 are arranged. In one example, the light-emitting region 38 has a substantially circular shape in a plan view. For convenience, in FIGS. 1 to 3, the light-emitting region 38 in which the plurality of light-emitting sections 33 are arranged is indicated by a dashed line.

[0016] As shown in Fig. 4, the surface-emitting laser element 30 has an element front surface electrode 34 formed on the element front surface 31, and an element back surface electrode 35 formed on the element back surface 32. As shown in Fig. 2, in a plan view, the element front surface electrode 34 is formed on a portion of the element front surface 31 where the light-emitting section 33 is not arranged. In one example, the element front surface electrode 34 is formed on the element front surface 31 closer to the second substrate side surface 24 in the X direction and substantially in the center of the element front surface 31 in the Y direction. The shape of the element front surface electrode 34 in a plan view is rectangular with the Y direction as the longitudinal direction and the X direction as the lateral direction.

[0017] The element surface electrode 34 may be shown as a member for externally connecting (wire WR) the surface-emitting laser element 30. In one example, the surface-emitting laser element 30 may include an electrode provided on the element surface 31 and electrically connected to a plurality of light-emitting sections 33. The electrode electrically connected to the light-emitting sections 33 may include the element surface electrode 34, or may be electrically connected to the element surface electrode 34.

[0018] 4, the element rear surface electrode 35 is formed to have, for example, the same size as the element rear surface 32. In one example, the element front surface electrode 34 constitutes an anode electrode, and the element rear surface electrode 35 constitutes a cathode electrode.

[0019] 2, the semiconductor light emitting device 10 has a first front surface electrode 61S and a second front surface electrode 62S provided on the substrate front surface 21. Furthermore, as shown in FIG 4, the semiconductor light emitting device 10 includes a first back surface electrode 63R and a second back surface electrode (not shown) provided on the substrate back surface 22, and a plurality of first vias 65 and second vias (not shown) provided in the substrate 20.

[0020] The first front surface electrode 61S, the second front surface electrode 62S, the first back surface electrode 63R, the second back surface electrode, the first via 65, and the second via are formed of a material including one or more appropriately selected from Ti (titanium), TiN (titanium nitride), Au (gold), Ag (silver), Cu (copper), Al (aluminum), and W (tungsten). The number of the first vias 65 can be changed arbitrarily. In one example, the number of the first vias 65 may be one. The number of the second vias may be one or more.

[0021] 2, the first surface electrode 61S is disposed at a position substantially in the center of the substrate surface 21 in the X direction and adjacent to the third substrate side surface 25 in the Y direction in a plan view. In one example, the first surface electrode 61S is formed in a rectangular shape with the X direction as the long side direction and the Y direction as the short side direction in a plan view. Note that the position and shape of the first surface electrode 61S with respect to the substrate surface 21 can be changed arbitrarily.

[0022] The second surface electrode 62S is disposed apart from the first surface electrode 61S in the Y direction. The second surface electrode 62S is disposed closer to the second substrate side surface 24 than the center of the substrate surface 21 in the X direction and closer to the fourth substrate side surface 26 than the center of the substrate surface 21 in the Y direction in a plan view. In one example, the second surface electrode 62S has a portion disposed at the same position as the element surface electrode 34 in the X direction. The second surface electrode 62S is formed in a rectangular shape with the X direction as the long side direction and the Y direction as the short side direction in a plan view. The shape and size of the second surface electrode 62S in a plan view can be changed arbitrarily.

[0023] As shown in Fig. 4, the surface-emitting laser element 30 is disposed on the first surface electrode 61S such that the element back surface electrode 35 faces the first surface electrode 61S. More specifically, the surface-emitting laser element 30 is bonded to the first surface electrode 61S by a conductive bonding material SD. This electrically connects the element back surface electrode 35 to the first surface electrode 61S. It can also be said that the surface-emitting laser element 30 is electrically connected to the first surface electrode 61S. As the conductive bonding material SD, for example, solder paste, silver paste, gold paste, copper paste, etc. may be used.

[0024] As shown in FIG. 2, a wire WR is connected to the element surface electrode 34 of the surface-emitting laser element 30. The wire WR is connected to the second surface electrode 62S. As a result, the element surface electrode 34 of the surface-emitting laser element 30 and the second surface electrode 62S are electrically connected via the wire WR. In the example shown in FIG. 2, the wire WR is formed so as to extend in the Y direction in a plan view. As shown in FIGS. 3 and 4, in this embodiment, the wire WR is sealed by a cover member 40. The wire WR is, for example, a bonding wire formed by a wire bonding device, and is made of a conductive material such as Au, Al, or Cu.

[0025] 4, the first back surface electrode 63R is formed approximately at the center in the X direction of the substrate back surface 22. In plan view, the first back surface electrode 63R includes a portion overlapping with the first front surface electrode 61S.

[0026] Although not shown, the second back surface electrode is disposed on the substrate back surface 22 and spaced apart from the first back surface electrode 63R in the Y direction. In a plan view, the second back surface electrode includes a portion overlapping with the second front surface electrode 62S.

[0027] As shown in Fig. 4, the first via 65 electrically connects the first front surface electrode 61S and the first back surface electrode 63R. The second via (not shown) electrically connects the second front surface electrode 62S and the second back surface electrode. Each of the first via 65 and the second via penetrates the substrate 20 in the Z direction. In the example shown in Fig. 4, three first vias 65 are provided.

[0028] The first back surface electrode 63R is electrically connected to the element back surface electrode 35 of the surface-emitting laser element 30 via the first front surface electrode 61S and the first via 65. The second back surface electrode is electrically connected to the element front surface electrode 34 of the surface-emitting laser element 30 via the second front surface electrode 62S, the second via, and the wire WR. In this manner, the semiconductor light-emitting device 10 is configured as a surface-mounted package structure.

[0029] 1, the semiconductor light emitting device 10 includes a cover member 40 that seals the first surface electrode 61S, the second surface electrode 62S, and the wire WR. As shown in FIG. 4, the cover member 40 contacts both the substrate surface 21 and the element surface 31.

[0030] 3, the dimension of the cover member 40 in the Y direction is equal to the dimension of the substrate surface 21 in the Y direction. The dimension of the cover member 40 in the X direction is smaller than the dimension of the substrate surface 21 in the X direction. Therefore, the substrate surface 21 includes the ends 27 exposed from both ends of the cover member 40 in the X direction. The dimensional relationship between the cover member 40 and the substrate surface 21 can be changed arbitrarily. In one example, the cover member 40 may cover the entire surface of the substrate surface 21 in a plan view.

[0031] The cover member 40 includes a peripheral wall 41 that surrounds the multiple light-emitting portions 33 in a circular shape in a plan view. The peripheral wall 41 is provided on the element surface 31 of the surface-emitting laser element 30. As shown in Fig. 3 and Fig. 4, the cover member 40 can be divided into the peripheral wall 41 that covers a portion of the element surface 31 of the surface-emitting laser element 30 that is closer to the element side surface 37 than the light-emitting region 38 in which the multiple light-emitting portions 33 are arranged, and a peripheral edge portion 44 that covers the element side surface 37.

[0032] The peripheral wall 41 of the cover member 40 surrounds the exposed portion 36 including the plurality of light-emitting portions 33 on the element surface 31. In other words, the peripheral wall 41 exposes the entirety of the plurality of light-emitting portions 33 in the Z direction.

[0033] 3, the inner surface 43 constituting the peripheral wall 41 surrounds the plurality of light-emitting units 33 in a circular shape in a plan view. In one example, the inner surface 43 is formed in a circular shape that is one size larger than the light-emitting region 38 in which the plurality of light-emitting units 33 are arranged in a plan view. The inner surface 43 may be formed in a circular shape that is the same size as the light-emitting region 38 in which the plurality of light-emitting units 33 are arranged in a plan view. The inner surface 43 may also be formed in a circular shape that is one size smaller than the light-emitting region 38 in which the plurality of light-emitting units 33 are arranged in a plan view.

[0034] The inner side surface 43 constituting the peripheral wall 41 is made of a mirror surface. That is, the inner side surface 43 is a smooth surface formed by mirror processing. In other words, the inner side surface 43 is made of a smooth surface that has been mirror processed. The mirror surface constituting the inner side surface 43 is configured to reflect the laser light of the surface-emitting laser element 30. In one example, at least the peripheral wall 41 is made of a light-transmitting material. In this embodiment, the entire cover member 40 is made of a light-transmitting material. In one example, the cover member 40 is made of a transparent resin. As the transparent resin, an acrylic resin, an epoxy resin, or the like can be used.

[0035] 4, the inner side surface 43 constituting the peripheral wall 41 extends along a direction perpendicular to the element surface 31. In other words, the inner side surface 43 extends along the direction in which the laser light of the surface-emitting laser element 30 is emitted.

[0036] The semiconductor light-emitting device 10 includes a diffusion layer 50 provided within the inner surface 43 of the peripheral wall 41. The diffusion layer 50 covers the entirety of the multiple light-emitting portions 33 of the surface-emitting laser element 30 in a plan view. In this embodiment, the diffusion layer 50 is in contact with the element surface 31 including the multiple light-emitting portions 33 of the surface-emitting laser element 30.

[0037] The diffusion layer 50 includes a light-transmitting resin layer 52 and a plurality of diffusion materials 51 provided in the resin layer 52. The diffusion materials 51 included in the diffusion layer 50 diffuse the laser light inside the diffusion layer 50 by reflecting light at the interface between the resin layer 52 and the diffusion materials 51.

[0038] The peripheral wall 41 includes a peripheral wall surface 42 facing the same side as the element surface 31. The diffusion layer 50 includes a surface 53 facing the same side as the element surface 31. The surface 53 of the diffusion layer 50 is located closer to the element surface 31 of the surface-emitting laser element 30 than the peripheral wall surface 42 of the peripheral wall 41. In this embodiment, the thickness DZ1 of the diffusion layer 50 is thinner than the thickness DZ2 of the surface-emitting laser element 30. The surface 53 of the diffusion layer 50 includes a flat surface along a direction parallel to the element surface 31.

[0039] The material of the diffusion material 51 is not particularly limited, but may be, for example, silica or other glass materials. In one example, a material having a smaller thermal expansion coefficient than the resin of the diffusion layer 50 is selected as the diffusion material 51.

[0040] In one example, spherical silica filler is used as the diffusion material 51. The particle size of the diffusion material 51 is not particularly limited, but for example, a particle size that is sufficiently small with respect to the wavelength of the laser light emitted from the surface-emitting laser element 30 is selected so that scattering occurs predominantly.

[0041] The diffusion material 51 is dispersed as fine particles in the diffusion layer 50. The diffusion material 51 is mixed with the diffusion layer 50 at a predetermined compounding ratio. In one example, the diffusion material 51 is uniformly dispersed in the diffusion layer 50. The compounding ratio of the diffusion material 51 to the resin of the diffusion layer 50 is not particularly limited, and may be greater than 0% and less than 100%. The larger the compounding ratio of the diffusion material 51 is, the more the laser light of the surface-emitting laser element 30 is diffused, so that the laser light of the multiple light-emitting parts 33 can be mixed together. In addition, by limiting the upper limit of the compounding ratio of the diffusion material 51 to a predetermined value, a large decrease in the output and radiation intensity of the laser light of the semiconductor light-emitting device 10 can be suppressed.

[0042] [Method of manufacturing a semiconductor light emitting device according to an embodiment] An example of a method for manufacturing the semiconductor light emitting device 10 will be described with reference to FIGS. 5 to 7 show schematic cross-sectional structures illustrating a method for manufacturing the semiconductor light emitting device 10 of the embodiment. The cross-sectional positions of Figures 5 to 7 are the same as the cross-sectional position of Figure 4 in plan view.

[0043] FIG. 5 shows a schematic cross-sectional structure of the semiconductor light emitting device 10 before the cover member 40 and the diffusion layer 50 are provided. 5, the manufacturing method of the semiconductor light emitting device 10 includes mounting the surface emitting laser element 30 on the substrate 20. More specifically, the surface emitting laser element 30 is mounted on a first surface electrode 61S of the substrate 20 having the first surface electrode 61S. The surface emitting laser element 30 includes an element front surface 31 on which a plurality of light emitting portions 33 are formed, and an element back surface 32 facing the opposite side to the element front surface 31. The surface emitting laser element 30 is mounted such that the element back surface 32 faces the first surface electrode 61S.

[0044] 6, the method for manufacturing the semiconductor light emitting device 10 includes forming the cover member 40. In this embodiment, the cover member 40 is formed by transfer molding.

[0045] The cover member 40 is formed to cover a portion of the element surface 31 of the surface-emitting laser element 30 closer to the element side surface 37 of the surface-emitting laser element 30 than a light-emitting region 38 in which multiple light-emitting portions 33 are arranged, and the element side surface 37.

[0046] In the cover member 40, the inner side surface 43 constituting the peripheral wall 41 is mirror-finished. Here, mirror-finishing refers to processing so that unevenness is extremely small. Therefore, the surface formed by mirror-finishing is a surface with extremely small unevenness. Mirror-finishing refers to indirect formation by a mirror-finished surface in a molding die or the like. In this embodiment, the surface forming the inner side surface 43 in the die for forming the cover member 40 is mirror-finished. Then, the inner side surface 43 is formed by the mirror-finished surface of the die. In this embodiment, the inner side surface 43 is flatter than other surfaces of the cover member 40 (for example, the peripheral wall surface 42 of the peripheral wall 41). The method of mirror-finishing the inner side surface 43 can be changed arbitrarily. For example, the mirror-finishing process may include polishing the inner side surface 43 and removing residues. The mirror-finishing process may also include a process of providing a protective layer for maintaining the mirror surface. The inner side surface 43 may also be provided with a reflective layer that reflects the laser light of the surface-emitting laser element 30.

[0047] As shown in FIG. 7, the method of manufacturing the semiconductor light emitting device 10 includes forming a diffusion layer 50 including a diffusion material 51 within a region surrounded by a peripheral wall 41. The diffusion layer 50 is formed so as to cover the entirety of the multiple light emitting sections 33 of the surface emitting laser element 30 within the region surrounded by the inner surface 43 of the peripheral wall 41. In this embodiment, the diffusion layer 50 is formed so as to be in contact with the multiple light emitting sections 33. In other words, the diffusion layer 50 is in contact with the element surface 31 including the multiple light emitting sections 33. The diffusion layer 50 is also formed so as to be in contact with the inner surface 43. Through the above steps, the semiconductor light emitting device 10 is manufactured.

[0048] It should be noted that other members may be interposed between the element surface 31 and the diffusion layer 50. For example, a light-transmitting layer may be interposed between the diffusion layer 50 and the element surface 31. In addition, other members may be interposed between the inner surface 43 and the diffusion layer 50. For example, a reflective layer or a protective layer may be provided on the inner surface 43, and these may be interposed between the inner surface 43 and the diffusion layer 50.

[0049] [Operation of the embodiment] The operation of the semiconductor light emitting device 10 of this embodiment will now be described. For example, some systems that use laser light, such as LiDAR, focus the laser light emitted from the multiple light-emitting units 33 of the surface-emitting laser element 30 using a lens and irradiate the laser light on an object. The laser light from the surface-emitting laser element 30, which is a VCSEL, has high directivity. Therefore, in the radiation pattern characteristics of the surface-emitting laser element 30 including multiple light-emitting units, for example, in the near-field pattern (NFP), the difference between the light intensity of each light-emitting unit 33 and the light intensity between the light-emitting units 33 is large. In other words, the surface-emitting laser element 30 including multiple light-emitting units 33 may have uneven brightness in the emitted laser light. When the surface-emitting laser element 30 including multiple light-emitting units 33 irradiates the laser light on an object through a lens, the laser light is irradiated in a spot-like manner on the irradiation surface of the object at positions corresponding to the multiple light-emitting units 33. Therefore, a difference occurs between the illuminance of the spot-irradiated area with the laser light and the illuminance of the surroundings of the spot-irradiated area. Therefore, there is a risk of shading occurring on the irradiation surface of the object.

[0050] Therefore, the semiconductor light emitting device 10 of this embodiment includes a diffusion layer 50 provided to cover the multiple light emitting sections 33. As a result, the laser light emitted from the multiple light emitting sections 33 is diffused by the diffusion layer 50, and the light intensity around each light emitting section 33 can be increased. This allows the semiconductor light emitting device 10 to reduce the intensity difference in the laser light in the vicinity. In other words, the semiconductor light emitting device 10 can reduce unevenness in the intensity distribution of the laser light in the vicinity. Therefore, the semiconductor light emitting device 10 can bring the laser light emitted from the multiple light emitting sections 33 closer to a state in which it is uniformly irradiated as if it were a single laser light. In this way, the semiconductor light emitting device 10 can improve the radiation pattern characteristic (NFP) of the emitted laser light.

[0051] [Effects of the embodiment] The semiconductor light emitting device 10 of this embodiment provides the following advantages. (1) The semiconductor light-emitting device 10 includes a surface-emitting laser element 30 including an element surface 31 on which a plurality of light-emitting portions 33 are formed, a peripheral wall 41 provided on the element surface 31 and surrounding the plurality of light-emitting portions 33 when viewed from a direction perpendicular to the element surface 31, and a diffusion layer 50 including a diffusion material 51 and provided within the area surrounded by the peripheral wall 41 so as to cover the plurality of light-emitting portions 33.

[0052] According to this configuration, the light emitted from the multiple light emitting portions 33 is diffused by the diffusion layer 50, so that the light can be made to approach a state in which it is emitted as a single laser beam, and the radiation pattern characteristics of the laser beam can be improved.

[0053] Furthermore, compared to a configuration in which the diffusion layer 50 is provided over the entire element surface 31 without providing the peripheral wall 41, the volume of the diffusion layer 50 can be made smaller, and therefore the material cost can be reduced. Furthermore, by providing diffusion layer 50 in a space narrower than in a configuration in which diffusion layer 50 is provided over the entire element surface 31 without providing peripheral wall 41, it is possible to reduce variation in the shape of surface 53 of diffusion layer 50 and thickness DZ1 of diffusion layer 50 between manufactured semiconductor light emitting devices 10. As a result, it is possible to reduce variation in the degree of light diffusion by diffusion layer 50 between manufactured semiconductor light emitting devices 10.

[0054] Furthermore, compared to a configuration in which the diffusion layer 50 is provided so as to cover the entire element surface 31 in a plan view, the formation area of ​​the diffusion layer 50 is narrowed by the peripheral wall 41. This makes it possible to suppress a decrease in the output of the laser light caused by the laser light being diffused over the entire element surface 31 in a plan view.

[0055] (2) Peripheral wall 41 includes a peripheral wall surface 42 facing the same side as element surface 31. Diffusion layer 50 includes a surface 53 facing the same side as element surface 31. Surface 53 of diffusion layer 50 is located closer to element surface 31 than peripheral wall surface 42 of peripheral wall 41.

[0056] According to this configuration, the surface 53 of the diffusion layer 50 is formed at a position closer to the element surface 31 than the peripheral wall surface 42 in the Z direction. Therefore, compared with a configuration in which the surface 53 of the diffusion layer 50 is provided on the opposite side of the element surface 31 with respect to the peripheral wall surface 42 in the Z direction, it is easier to make the thickness DZ1 of the diffusion layer 50 and the shape of the surface 53 uniform. Therefore, it is possible to suppress the occurrence of uneven brightness due to differences in the degree to which the laser light emitted from the multiple light-emitting parts 33 is diffused by the diffusion layer 50. In addition, it is possible to reduce the variation in the thickness DZ1 of the diffusion layer 50 and the shape of the surface 53 between products of the semiconductor light-emitting device 10. Therefore, it is possible to reduce the variation in the degree to which the laser light is diffused by the diffusion layer 50 between products of the semiconductor light-emitting device 10.

[0057] When the surface 53 of the diffusion layer 50 is close to the peripheral wall surface 42 of the peripheral wall 41, the laser light diffused by the diffusion layer 50 is likely to be emitted outward from the diffusion layer 50 in a planar view. In other words, the beam angle is likely to be wide. In contrast, by positioning the surface 53 of the diffusion layer 50 closer to the element surface 31, the spread of the beam angle can be suppressed. Furthermore, the light intensity in the Z direction perpendicular to the element surface 31 can be improved.

[0058] (3) The inner surface 43 constituting the peripheral wall 41 is formed of a mirror surface. According to this configuration, the light diffused by the diffusion layer 50 is reflected by the inner surface 43 formed of a mirror surface. The reflected light is then emitted to the outside of the semiconductor light emitting device 10. Therefore, by preventing the diffused light from entering the peripheral wall 41 of the semiconductor light emitting device 10, a decrease in the light output can be suppressed.

[0059] (4) The inner surface 43 constituting the peripheral wall 41 is circular when viewed in a direction perpendicular to the element surface 31 . According to this configuration, the multiple light-emitting sections 33 are surrounded by a circular mirror surface when viewed from a direction perpendicular to the element surface 31. Therefore, compared to a configuration in which the multiple light-emitting sections 33 are surrounded by a non-circular mirror surface when viewed from a direction perpendicular to the element surface 31, it is possible to approach a state in which the light emitted from the multiple light-emitting sections 33 is emitted like a single circular light, and it is possible to improve the radiation pattern characteristics.

[0060] (5) The inner surface 43 constituting the peripheral wall 41 extends in a direction perpendicular to the element surface 31 . According to this configuration, it is possible to suppress the light from being emitted in a spreading manner, compared to a configuration in which the inner surface 43 constituting the peripheral wall 41 spreads out as it moves away from the element surface 31 in a cross section viewed from a direction perpendicular to the element surface 31.

[0061] (6) The diffusion layer 50 includes a surface 53 facing the same side as the element surface 31. The surface 53 of the diffusion layer 50 includes a flat surface along a direction parallel to the element surface 31. This configuration can reduce variations in the shape of surface 53 of diffusion layer 50 and thickness DZ1 of diffusion layer 50, compared to when surface 53 of diffusion layer 50 has an uneven structure. This can reduce variations in the degree of diffusion by diffusion layer 50 between products.

[0062] <Example of change> The above embodiment can be modified, for example, as follows. The above embodiment and the following modified examples can be combined with each other as long as no technical contradiction occurs. In the following modified examples, the same reference numerals as in the above embodiment are used for the parts common to the above embodiment, and the description thereof will be omitted.

[0063] 8, the diffusion layer 50 does not have to be in contact with the light-emitting sections 33 of the surface-emitting laser element 30. In one example, the diffusion layer 50 may include a transparent member 70 that is in contact with a plurality of light-emitting sections 33 within the region surrounded by the peripheral wall 41. In this case, the diffusion layer 50 is provided on the transparent member 70. Note that the cross-sectional position in FIG. 8 is the same as the cross-sectional position in FIG. 4 in plan view.

[0064] The peripheral wall 41 does not have to extend along a direction perpendicular to the element surface 31. In one example, the peripheral wall 41 may be configured such that an inner surface 43 constituting the peripheral wall 41 widens as it moves away from the element surface 31.

[0065] Peripheral wall 41 may be made of a light-shielding material. In one example, peripheral wall 41 may be made of a white resin that reflects the laser light of semiconductor light emitting device 10.

[0066] The step of mirror-finishing the inner surface 43 of the peripheral wall 41 may include attaching a film or applying a coating material to maintain the mirror reflection. A reflective layer that reflects laser light may be formed on the inner surface 43 of the peripheral wall 41. The reflective layer is formed of, for example, a thin metal film or a film with high reflectivity.

[0067] The position in the Z direction where the surface 53 of the diffusion layer 50 is formed can be changed arbitrarily. The surface 53 of the diffusion layer 50 may be formed so as not to protrude in the opposite direction of the element surface 31 from the peripheral wall surface 42 of the peripheral wall 41. In one example, the surface 53 of the diffusion layer 50 may be flush with the peripheral wall surface 42 of the peripheral wall 41.

[0068] The shape of the cover member 40 can be changed as desired. The cover member 40 only needs to expose the multiple light-emitting sections 33 in the Z direction. For example, the cover member 40 does not need to seal the element side surface 37 of the surface-emitting laser element 30. Furthermore, the cover member 40 may expose the first surface electrode 61S, the second surface electrode 62S, and parts of the element surface electrode 34.

[0069] The thickness DZ1 of the diffusion layer 50 does not have to be thinner than the thickness DZ2 of the surface-emitting laser element 30. The thickness DZ1 of the diffusion layer 50 may be thicker than the thickness DZ2 of the surface-emitting laser element 30, or may be equal to the thickness DZ2 of the surface-emitting laser element 30.

[0070] The method of forming the cover member 40 can be changed as desired. In one example, the cover member 40 may be formed by compression molding. One or more of the various examples described in this specification may be combined to the extent that they are not technically inconsistent.

[0071] The terms "first", "second", "third", etc. in this disclosure are used merely to distinguish objects and do not rank the objects. In this specification, "at least one of A and B" should be understood to mean "A only, or B only, or both A and B."

[0072] The term "on" as used in this disclosure includes the meanings "on" and "above" unless the context clearly indicates otherwise. Thus, for example, the expression "a first element is disposed on a second element" is intended to mean that in some embodiments, the first element may be disposed directly on the second element in contact with the second element, while in other embodiments, the first element may be disposed above the second element without contacting the second element. In other words, the term "on" does not exclude a structure in which another element is formed between the first element and the second element.

[0073] The Z direction used in this disclosure does not necessarily have to be a vertical direction, nor does it have to completely coincide with the vertical direction. Therefore, various structures according to this disclosure are not limited to the "up" and "down" of the Z direction described in this specification being "up" and "down" of the vertical direction. For example, the X direction may be a vertical direction, or the Y direction may be a vertical direction.

[0074] <Additional Notes> The technical ideas that can be understood from this disclosure are described below. Note that, for the purpose of aiding understanding, not for the purpose of limitation, the components described in the appendices are given the reference numbers of the corresponding components in the above embodiment. The reference numbers are shown as examples to aid understanding, and the components described in each appendix should not be limited to the components indicated by the reference numbers.

[0075] [Appendix 1] a surface-emitting laser element (30) including an element surface (31) on which a plurality of light-emitting portions (33) are formed; a peripheral wall (41) provided on the element surface (31) and surrounding the plurality of light-emitting sections (33) when viewed from a direction perpendicular to the element surface (31); a diffusion layer (50) that is provided within the region surrounded by the peripheral wall (41) so as to cover the plurality of light emitting sections (33) and that includes a diffusion material (51); A semiconductor light emitting device (10).

[0076] [Appendix 2] The diffusion layer (50) is in contact with the plurality of light emitting portions (33). 2. The semiconductor light emitting device of claim 1.

[0077] [Appendix 3] The peripheral wall (41) includes a peripheral wall surface (42) facing the same side as the element surface (31), The diffusion layer (50) includes a surface (53) facing the same side as the element surface (31); The surface (53) of the diffusion layer (50) is located closer to the element surface (31) than the peripheral wall surface (42) of the peripheral wall (41). 3. The semiconductor light emitting device according to claim 1 or 2.

[0078] [Appendix 4] The inner surface (43) constituting the peripheral wall (41) is formed of a mirror surface. 4. The semiconductor light emitting device according to claim 1.

[0079] [Appendix 5] The peripheral wall (41) is made of a light-transmitting material. 5. The semiconductor light emitting device according to claim 1.

[0080] [Appendix 6] The peripheral wall (41) is made of a light-shielding material. 5. The semiconductor light emitting device according to claim 1.

[0081] [Appendix 7] The inner surface (43) constituting the peripheral wall (41) is circular when viewed in a direction perpendicular to the element surface (31). 7. The semiconductor light emitting device according to claim 1.

[0082] [Appendix 8] The inner surface (43) constituting the peripheral wall (41) extends along a direction perpendicular to the element surface (31). 8. The semiconductor light emitting device according to claim 1.

[0083] [Appendix 9] The diffusion layer (50) includes a surface (53) facing the same side as the element surface (31); The surface (53) of the diffusion layer (50) includes a flat surface along a direction parallel to the element surface (31). 9. The semiconductor light emitting device according to claim 1.

[0084] [Appendix 10] a transparent member (70) in contact with an inner surface (43) of the peripheral wall (41) and the plurality of light emitting portions (33), The diffusion layer (50) is provided on the transparent member (70). 10. The semiconductor light emitting device according to any one of claims 1 to 9.

[0085] [Appendix 11] The surface emitting laser element (30) is A back surface (32) of the element facing the opposite side to the front surface (31) of the element; an element side surface (37) connecting the element front surface (31) and the element back surface (32); Including, A substrate (20) supporting the surface-emitting laser element (30); a cover member (40) including the peripheral wall (41), covering a portion of the element surface (31) of the surface-emitting laser element (30) closer to the element side surface (37) than a light-emitting region (38) in which the plurality of light-emitting portions (33) are arranged, and the element side surface (37); Includes 11. The semiconductor light emitting device according to any one of claims 1 to 10.

[0086] [Appendix 12] The thickness (DZ1) of the diffusion layer (50) is smaller than the thickness (DZ2) of the surface-emitting laser element. 12. The semiconductor light emitting device according to claim 1.

[0087] [Appendix 13] Mounting a surface-emitting laser element (30) including an element surface (31) on which a plurality of light-emitting portions (33) are formed on a substrate (20); forming a cover member (40) including a peripheral wall (41) surrounding the plurality of light-emitting portions (33) on the element surface (31) when viewed from a direction perpendicular to the element surface (31), and covering a portion of the element surface (31) of the surface-emitting laser element (30) closer to an element side surface (37) of the surface-emitting laser element (30) than a light-emitting region (38) in which the plurality of light-emitting portions (33) are arranged, and the element side surface (37); forming a diffusion layer (50) including a diffusion material (51) within a region surrounded by the peripheral wall (41); A method for manufacturing a semiconductor light emitting device, comprising:

[0088] [Appendix 14] The cover member (40) is formed by transfer molding. A method for manufacturing the semiconductor light emitting device according to claim 13.

[0089] [Appendix 15] The inner surface (43) constituting the peripheral wall (41) is mirror-finished. 15. A method for manufacturing a semiconductor light-emitting device according to claim 13 or 14.

[0090] The above description is merely illustrative. Those skilled in the art may recognize that many more possible combinations and permutations are possible other than the components and methods (manufacturing processes) listed for the purpose of describing the technology of the present disclosure. The present disclosure is intended to embrace all alternatives, modifications, and alterations that fall within the scope of the present disclosure, including the scope of the claims. [Explanation of symbols]

[0091] 10...Semiconductor light-emitting device 20...Substrate 21...Substrate surface 22…Back side of board 23~26...1st~4th board side 27...End 30... Surface emitting laser element 31...Element surface 32…Back side of element 33…Light emitting part 34: Element surface electrode 35…Back electrode of element 36...Exposed part 37…Side of element 38…Light emitting area 40…Cover member 41...peripheral wall 42...Surrounding wall surface 43…Inner surface 44…periphery 50...Diffusion layer 51...Diffusion material 52...Resin layer 53…Surface 61S…1st surface electrode 62S…Second surface electrode 63R…First rear electrode 65…First via 70...Transparent material DZ1: Thickness of the diffusion layer DZ2: Thickness of surface-emitting laser element SD: Conductive adhesive WR…Wire

Claims

1. a surface-emitting laser element including an element surface on which a plurality of light-emitting portions are formed; a peripheral wall provided on a surface of the element and surrounding the plurality of light-emitting portions when viewed in a direction perpendicular to the surface of the element; a diffusion layer including a diffusion material, the diffusion layer being provided within the region surrounded by the peripheral wall so as to cover the plurality of light emitting portions; A semiconductor light emitting device comprising:

2. The diffusion layer is in contact with the plurality of light emitting portions. The semiconductor light emitting device according to claim 1 .

3. the peripheral wall includes a peripheral wall surface facing the same side as the element surface; the diffusion layer includes a surface facing the same side as the device surface; The surface of the diffusion layer is located closer to the element surface than the peripheral wall surface of the peripheral wall. The semiconductor light emitting device according to claim 1 .

4. The inner surface constituting the peripheral wall is formed of a mirror surface. The semiconductor light emitting device according to claim 1 .

5. The peripheral wall is made of a light-transmitting material. The semiconductor light emitting device according to claim 4 .

6. The inner surface constituting the peripheral wall is circular when viewed from a direction perpendicular to the element surface. The semiconductor light emitting device according to claim 1 .

7. The inner surface constituting the peripheral wall extends in a direction perpendicular to the surface of the element. The semiconductor light emitting device according to claim 1 .

8. the diffusion layer includes a surface facing the same side as the device surface; The surface of the diffusion layer includes a flat surface along a direction parallel to the surface of the element. The semiconductor light emitting device according to claim 1 .

9. a transparent member in contact with an inner surface of the peripheral wall and the plurality of light emitting units; The diffusion layer is provided on the transparent member. The semiconductor light emitting device according to claim 1 .

10. The surface emitting laser element is a back surface of the element facing away from the front surface of the element; an element side surface connecting the element front surface and the element back surface; Including, a substrate supporting the surface-emitting laser element; a cover member including the peripheral wall, the cover member covering a portion of the surface of the surface-emitting laser element closer to the element side surface than a light-emitting region in which the plurality of light-emitting portions are arranged, and the element side surface; Includes The semiconductor light emitting device according to claim 1 .

11. The thickness of the diffusion layer is smaller than the thickness of the surface-emitting laser element. The semiconductor light emitting device according to claim 1 .

12. Mounting a surface-emitting laser element including an element surface on which a plurality of light-emitting portions are formed on a substrate; forming a cover member including a peripheral wall surrounding the plurality of light-emitting portions on the element surface when viewed from a direction perpendicular to the element surface, the cover member covering a portion of the element surface of the surface-emitting laser element closer to an element side surface of the surface-emitting laser element than a light-emitting region in which the plurality of light-emitting portions are arranged, and the element side surface; forming a diffusion layer including a diffusion material within the region surrounded by the peripheral wall; A method for manufacturing a semiconductor light emitting device, comprising:

13. The cover member is formed by transfer molding. The method for manufacturing the semiconductor light emitting device according to claim 12 .

14. The inner surface constituting the peripheral wall is mirror-finished. The method for manufacturing the semiconductor light emitting device according to claim 12 .

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