Semiconductor light-emitting device

Abstract

This semiconductor light-emitting device includes a semiconductor light-emitting element mounted on a first substrate surface of a substrate, and a drive circuit for driving the semiconductor light-emitting element. The substrate includes a second surface electrode and a first surface electrode. The semiconductor light-emitting element includes: a first element surface that includes a light-emitting region from which light is emitted; an anode electrode that is provided on the side opposite from the first element surface and is electrically connected to the second surface electrode; a cathode electrode that is provided on the side opposite from the first element surface and is electrically connected to the first surface electrode; a semiconductor substrate; and a semiconductor layer that is configured to generate light. The semiconductor light-emitting element is mounted on the substrate such that the semiconductor layer is disposed between the semiconductor substrate and the substrate in a Z-axis direction.

Description

Semiconductor light-emitting device

[0001] The present disclosure relates to semiconductor light emitting devices.

[0002] 2. Description of the Related Art As an example of a semiconductor light emitting device, a semiconductor laser device including a semiconductor laser element as a light source is known. Semiconductor laser devices are widely used as light source devices mounted in various electronic devices. Patent Document 1 discloses an example of a semiconductor laser device.

[0003] JP 2016-29718 A

[0004] [Summary] There is a demand for reducing inductance in semiconductor light emitting devices.

[0005] a back electrode layer provided on the second substrate surface; and a semiconductor substrate including a first element surface including a light-emitting region that emits light, an anode electrode provided on the opposite side of the first element surface and electrically connected to the front-side anode electrode, a cathode electrode provided on the opposite side of the first element surface and electrically connected to the front-side cathode electrode, a first surface, and a second surface opposite the first surface and constituting the first element surface; and a semiconductor layer provided on the first surface and configured to generate light, and the semiconductor layer is mounted on the substrate so that the semiconductor layer is disposed between the semiconductor substrate and the substrate in a thickness direction of the substrate.

[0006] FIG. 1 is a schematic plan view of an exemplary semiconductor light-emitting device according to a first embodiment. FIG. 2 is a schematic plan view showing an enlarged central region of the semiconductor light-emitting device of FIG. 1. FIG. 3 is a schematic plan view showing an enlarged first partitioned region when the substrate of the semiconductor light-emitting device of FIG. 1 is partitioned into four partitioned regions. FIG. 4 is a schematic plan view showing an enlarged second partitioned region when the substrate of the semiconductor light-emitting device of FIG. 1 is partitioned into four partitioned regions. FIG. 5 is a schematic plan view showing an enlarged third partitioned region when the substrate of the semiconductor light-emitting device of FIG. 1 is partitioned into four partitioned regions. FIG. 6 is a schematic plan view showing an enlarged fourth partitioned region when the substrate of the semiconductor light-emitting device of FIG. 1 is partitioned into four partitioned regions. FIG. 7 is a schematic cross-sectional view of the semiconductor light-emitting device taken along line F7-F7 in FIG. 3. FIG. 8 is a schematic perspective view showing the back surface structure of the semiconductor light-emitting device of FIG. 1. FIG. 9 is a schematic plan view of an intermediate electrode layer on the front surface side of the semiconductor light-emitting device of FIG. 1. FIG. 10 is a schematic plan view of an intermediate electrode layer on the back surface side of the semiconductor light-emitting device of FIG. 1. FIG. 11 is a circuit diagram showing a circuit configuration of a portion of an exemplary light-emitting system including the semiconductor light-emitting device of FIG. 1. FIG. 12 is a circuit diagram showing a circuit configuration of the remaining portion of the light-emitting system of FIG. 11. FIG. 13 is a schematic perspective view of a submount substrate and a semiconductor light-emitting element mounted on the submount substrate. FIG. 14 is a schematic cross-sectional view of the submount substrate and the semiconductor light-emitting element mounted on a substrate. FIG. 15 is a schematic plan view of the submount substrate. FIG. 16 is a schematic back view of the submount substrate. FIG. 17 is a schematic cross-sectional view of the semiconductor light-emitting element. FIG. 18 is a schematic back view of the semiconductor light-emitting element. FIG. 19 is a schematic cross-sectional view showing a current path in the semiconductor light-emitting device of FIG. 7. FIG. 20 is a schematic plan view of an exemplary semiconductor light-emitting device according to a second embodiment. FIG. 21 is a schematic plan view showing an enlarged first partition region when the substrate of the semiconductor light-emitting device of FIG. 20 is partitioned into four partition regions. FIG. 22 is a schematic perspective view of the semiconductor light-emitting device of FIG. 20. FIG. 23 is a schematic cross-sectional view of the semiconductor light-emitting device taken along line F23-F23 of FIG. 21. Fig. 24 is a schematic cross-sectional view of the semiconductor light emitting device taken along line F24-F24 in Fig. 21. Fig. 25 is a schematic plan view of the submount substrate. Fig. 26 is a schematic back view of the submount substrate. Fig. 27 is a schematic plan view of an exemplary semiconductor light emitting device according to a third embodiment.FIG. 28 is a schematic plan view showing an enlarged first partition region when the substrate of the semiconductor light emitting device of FIG. 27 is partitioned into four partition regions. FIG. 29 is a schematic perspective view of the semiconductor light emitting device of FIG. 27. FIG. 30 is a schematic cross-sectional view of the semiconductor light emitting device taken along line F30-F30 in FIG. 28. FIG. 31 is a schematic cross-sectional view of the semiconductor light emitting device taken along line F31-F31 in FIG. 28. FIG. 32 is a schematic plan view of a submount substrate. FIG. 33 is a schematic back view of the submount substrate. FIG. 34 is a schematic cross-sectional view showing an exemplary manufacturing step in a method for manufacturing the semiconductor light emitting device of FIG. 27. FIG. 35 is a schematic cross-sectional view showing an exemplary manufacturing step subsequent to FIG. 34. FIG. 36 is a schematic cross-sectional view showing an exemplary manufacturing step subsequent to FIG. 35. FIG. 37 is a schematic cross-sectional view showing an exemplary manufacturing step subsequent to FIG. 36. FIG. 38 is a schematic cross-sectional view showing an exemplary manufacturing step subsequent to FIG. 37. FIG. 39 is a schematic cross-sectional view showing an exemplary manufacturing step subsequent to FIG. 38. FIG. 40 is a schematic plan view of an exemplary semiconductor light emitting device according to a fourth embodiment. Fig. 41 is a schematic perspective view of the semiconductor light emitting device of Fig. 40. Fig. 42 is a schematic cross-sectional view of a semiconductor light emitting element of a modified example.

[0007] DETAILED DESCRIPTION Hereinafter, several embodiments of semiconductor light-emitting devices according to the present disclosure will be described with reference to the accompanying drawings. Note that for simplicity and clarity of description, 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 to limit 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] The phrase "at least one" as used in this disclosure means "one or more" of the desired options. As an example, the phrase "at least one" as used in this disclosure means "only one option" or "both of two options" when the number of options is two. As another example, the phrase "at least one" as used in this disclosure means "only one option" or "any combination of two or more options" when the number of options is three or more.

[0010] As used in the present disclosure, "the dimensions (depth, width, length) of A are equal to the dimensions (depth, width, length) of B" or "the dimensions (depth, width, length) of A and the dimensions (depth, width, length) of B are equal to each other" also includes a relationship in which the difference between the dimensions (depth, width, length) of A and the dimensions (depth, width, length) of B is, for example, within 10% of the dimensions (depth, width, length) of A.

[0011] First Embodiment [Overall Configuration of Semiconductor Light-Emitting Device] The overall configuration of a semiconductor light-emitting device 10 according to a first embodiment will be described with reference to FIGS. 1 to 10. FIG. 1 schematically illustrates the planar structure of the semiconductor light-emitting device 10. FIG. 2 schematically illustrates the planar structure of a central portion of the semiconductor light-emitting device 10 of FIG. 1. FIGS. 3 to 6 schematically illustrate the planar structures of four different regions of the semiconductor light-emitting device 10. FIG. 7 schematically illustrates a cross-sectional structure of the semiconductor light-emitting device 10 taken along line F7-F7 in FIG. 3. FIG. 8 schematically illustrates the rear surface structure of the semiconductor light-emitting device 10. FIG. 9 schematically illustrates the planar structure of a third electrode layer 28C (described later) of the semiconductor light-emitting device 10. FIG. 10 schematically illustrates the planar structure of a fourth electrode layer 28D (described later) of the semiconductor light-emitting device 10.

[0012] In this disclosure, components may be described based on mutually orthogonal X, Y, and Z axes shown in the drawings. The term "planar view" used in this disclosure refers to viewing the semiconductor light-emitting device 10 in the Z-axis direction.

[0013] 1, the semiconductor light emitting device 10 includes a substrate 20, a plurality of (e.g., eight in FIG. 1) semiconductor light emitting elements 30A-30H, and a plurality of (e.g., eight in FIG. 1) drive circuits 40A-40H. The semiconductor light emitting device 10 may include at least one semiconductor light emitting element and at least one drive circuit.

[0014] The plurality of semiconductor light-emitting elements 30A-30H and the plurality of drive circuits 40A-40H are provided on a substrate 20. The semiconductor light-emitting device 10 is embodied as a multi-channel (eight channels in the example of FIG. 1 ) drive-type light-emitting module in which the plurality of semiconductor light-emitting elements 30A-30H are driven by the plurality of drive circuits 40A-40H. Note that the number of semiconductor light-emitting elements 30A-30H and the number of drive circuits 40A-40H can be changed as appropriate depending on the number of channels.

[0015] The substrate 20 is rectangular in plan view. In the example of FIG. 1 , the substrate 20 is rectangular in plan view, with the longer side oriented in the X-axis direction and the shorter side oriented in the Y-axis direction. The shape of the substrate 20 in plan view can be arbitrarily changed. For example, the substrate 20 may be square in plan view. Here, "plan view" is synonymous with viewing the semiconductor light-emitting device 10 in the thickness direction of the substrate 20 (the direction perpendicular to the paper surface in FIG. 1 ). The substrate 20 includes a first substrate surface 21, a second substrate surface 22 (see FIG. 7 ) opposite the first substrate surface 21, and four side surfaces, first to fourth side surfaces 23 to 26, connecting the first substrate surface 21 and the second substrate surface 22. The first side surface 23 and the second side surface 24 constitute both end surfaces of the substrate 20 in the Y-axis direction. The third side surface 25 and the fourth side surface 26 constitute both end surfaces of the substrate 20 in the X-axis direction.

[0016] 7, for example, a multilayer substrate is used for the substrate 20. In the example shown in FIG. 7, the substrate 20 is a four-layer substrate including first to fourth electrode layers 28A to 28D and first to third base materials 27A to 27C located between the first to fourth electrode layers 28A to 28D. The first to fourth electrode layers 28A to 28D are made of one or more materials selected from the group including, for example, Ti (titanium), TiN (titanium nitride), Au (gold), Ag (silver), Cu (copper), Al (aluminum), and W (tungsten).

[0017] The first to third base materials 27A to 27C are made of, for example, an insulating material. One example of the insulating material is a material containing epoxy resin, and for example, glass epoxy resin may be used. Another example of the insulating material is a material containing ceramic. Examples of the material containing ceramic include AlN (aluminum nitride) or Al ２ O ３ (alumina) may be used. When a material containing ceramic is used, the heat dissipation performance of the first to third base materials 27A to 27C is improved, thereby suppressing excessive temperature rise in the semiconductor light emitting device 10. The first to third base materials 27A to 27C may be made of a material containing Si (silicon).

[0018] The first substrate 27A includes the first substrate surface 21 of the substrate 20. The second substrate 27B includes the second substrate surface 22 of the substrate 20. In other words, the main surface of the first substrate 27A corresponds to the first substrate surface 21 of the substrate 20, and the back surface of the second substrate 27B corresponds to the second substrate surface 22 of the substrate 20. The third substrate 27C is located midway between the first substrate 27A and the second substrate 27B. The four side surfaces of each of the first to third substrates 27A to 27C correspond to the first to fourth side surfaces 23 to 26 of the substrate 20 (see FIG. 1).

[0019] The first substrate surface 21 of the substrate 20 is covered with a main surface resist layer 29A. The second substrate surface 22 of the substrate 20 is covered with a back surface resist layer 29B. The main surface resist layer 29A and the back surface resist layer 29B are made of an insulating material such as an epoxy resin or a polyimide resin. The main surface resist layer 29A and the back surface resist layer 29B may contain a filler such as silica or alumina.

[0020] In the example shown in Figure 7, the ends of the first to fourth electrode layers 28A to 28D are not exposed on the first to fourth side surfaces 23 to 26 of the substrate 20. The end of the first electrode layer 28A located on the first substrate surface 21 of the substrate 20 is covered by a main surface resist layer 29A. The end of the second electrode layer 28B located on the second substrate surface 22 of the substrate 20 is covered by a back surface resist layer 29B. The third electrode layer 28C and the fourth electrode layer 28D located between the first to third substrates 27A to 27C are covered by the first to third substrates 27A to 27C. In Figure 7, for the purpose of explanation, the interfaces between the first to third substrates 27A to 27C are shown with solid lines, but in reality, these interfaces may not be clearly defined.

[0021] [Schematic Configuration of Semiconductor Light-Emitting Device] As shown in FIG. 1 , each of the semiconductor light-emitting elements 30A-30H is disposed on the first substrate surface 21 of the substrate 20. Each of the semiconductor light-emitting elements 30A-30H is configured as a light-emitting element that emits light in a direction intersecting the first substrate surface 21 (the Z-axis direction in FIG. 1 ), and functions as a light source for the semiconductor light-emitting device 10. In one example, each of the semiconductor light-emitting elements 30A-30H is disposed on the first substrate surface 21 of the substrate 20 via a first electrode layer 28A. The semiconductor light-emitting elements 30A-30H are surface-emitting laser elements. In one example, each of the semiconductor light-emitting elements 30A-30H is configured as a photonic-crystal surface-emitting laser (PCSEL) element that outputs laser light in a predetermined wavelength band. PCSEL elements are capable of high-power operation (high-brightness operation) by emitting a beam with high beam quality and a narrow divergence angle, and are characterized by low temperature dependence of the operating wavelength. In one example, the semiconductor light-emitting elements 30A-30H have the same configuration. For example, the PCSEL element employed in each of the semiconductor light-emitting elements 30A-30H has a beam divergence angle, expressed by the full width at half maximum (FWHM), of 1° or less, more preferably 0.10° to 0.15°, and a spectral width of 0.2 nm or less. The PCSEL element has, for example, a device size of approximately 1.0 mm × 1.0 mm in plan view and a thickness of 0.2 mm or less. The laser light may be visible light or laser light with a wavelength longer than visible light, such as infrared light.

[0022] As shown in FIGS. 1 and 2 , each of the semiconductor light-emitting elements 30A-30H has a rectangular shape, e.g., a square shape, in a plan view. The semiconductor light-emitting elements 30A-30H are collectively arranged in a central region AC of the substrate 20. The central region AC refers to a region including the center of the substrate 20 in a plan view. In one example, the semiconductor light-emitting elements 30A-30D are arranged in a row in the X-axis direction within the central region AC, and the semiconductor light-emitting elements 30E-30H are arranged in a row in the X-axis direction within the central region AC, adjacent to the semiconductor light-emitting elements 30A-30D in the Y-axis direction. Therefore, the semiconductor light-emitting elements 30A-30H are arranged in a matrix adjacent to one another in the central region AC of the substrate 20. The arrangement of the semiconductor light-emitting elements 30A-30H is not limited to the two rows and four columns shown in FIG. 1 .

[0023] As shown in FIG. 7 , the semiconductor light emitting element 30A includes a first element surface 31 and a second element surface 32 opposite the first element surface 31. As shown in FIG. 3 , the semiconductor light emitting element 30A includes a light emitting region 33 that emits light. The light emitting region 33 is provided in the center of the first element surface 31. The light emitting region 33 is configured to emit light in a direction perpendicular to the first element surface 31. An anode electrode 34 and a cathode electrode 35 are provided on the side opposite the first element surface 31. Parts of the surfaces of the anode electrode 34 and the cathode electrode 35 form the second element surface 32. Note that, like the semiconductor light emitting element 30A, the semiconductor light emitting elements 30B to 30H also have a first element surface 31, a second element surface 32, and a light emitting region 33. The detailed configurations of the semiconductor light emitting elements 30A to 30H will be described later.

[0024] [Overview of the Drive Circuit] As shown in FIG. 1, multiple drive circuits 40A-40H are provided to drive corresponding semiconductor light-emitting elements among the multiple semiconductor light-emitting elements 30A-30H. Each of these drive circuits 40A-40H is configured to drive one or more of the multiple semiconductor light-emitting elements 30A-30H. In the example of FIG. 1, one semiconductor light-emitting element is provided per channel (drive circuit), and therefore each of the drive circuits 40A-40H drives a corresponding one of the semiconductor light-emitting elements 30A-30H. Note that the drive circuits 40A-40H have the same configuration, so the following description will focus on the configuration of the drive circuit 40A, and detailed descriptions of the drive circuits 40B-40H will be omitted.

[0025] The drive circuit 40A includes a switching element 411 and one or more capacitors 421. The switching element 411 is configured to control one or more of the semiconductor light emitting elements 30A to 30H. In the example of FIG. 1, the switching element 411 drives one of the eight semiconductor light emitting elements 30A to 30H (semiconductor light emitting element 30A in the case of the drive circuit 40A). The switching element 411 is provided near the semiconductor light emitting element 30A that is to be driven. In the example of FIG. 1, the switching element 411 is provided in a position close to the semiconductor light emitting element 30A in the Y-axis direction.

[0026] The switching element 411 has a rectangular shape in a plan view. In the example of FIG. 1 , the switching element 411 has a square shape in a plan view. The shape of the switching element 411 in a plan view can be changed as desired. For example, a horizontal transistor is used as the switching element 411. An example of such a horizontal transistor is a high electron mobility transistor (HEMT) made of a nitride semiconductor such as gallium nitride (GaN). Note that a metal-oxide-semiconductor field-effect transistor (MOSFET) may also be used as the switching element 411 as long as it is a horizontal transistor.

[0027] As shown in FIG. 3 , the switching element 411 includes a first element surface 41A and a second element surface 41B (see FIG. 7 ) opposite the first element surface 41A. The second element surface 41B is provided with a drain electrode 41D, a plurality of source electrodes 41S (two in the example of FIG. 3 ), and a gate electrode 41G. The drain electrode 41D and the plurality of source electrodes 41S are alternately arranged in the X-axis direction on the second element surface 41B. Therefore, the drain electrode 41D is disposed between the source electrodes 41S arranged in the X-axis direction. The gate electrode 41G is disposed, for example, near one corner of the second element surface 41B. The gate electrode 41G and the source electrode 41S are arranged in the Y-axis direction.

[0028] Although not shown, a plurality of drain electrodes 41D (e.g., three) may be arranged side by side in the Y-axis direction. Each source electrode 41S may have a plurality of source electrodes 41S (e.g., two or three) arranged side by side in the Y-axis direction. In one example, the source electrode 41S arranged side by side with the gate electrode 41G in the Y-axis direction may have a configuration in which two source electrodes 41S are arranged side by side in the Y-axis direction. Three source electrodes 41S arranged on the opposite side of the drain electrode 41D from the gate electrode 41G may be arranged side by side in the Y-axis direction.

[0029] As shown in Fig. 1, the capacitor 421 is configured to supply current to one or more of the multiple semiconductor light-emitting elements 30A to 30H. In the example shown in Fig. 3, the drive circuit 40A includes four capacitors 421 connected in parallel. These four capacitors 421 are configured to supply current to the semiconductor light-emitting element 30A that is to be driven by the switching element 411. The four capacitors 421 are provided in positions adjacent to or close to the switching element 411 in the Y-axis direction. The four capacitors 421 are arranged closer to the first side surface 23 of the substrate 20 than the switching element 411 in the Y-axis direction.

[0030] The capacitors 421 are, for example, ceramic capacitors. Each capacitor 421 is rectangular in plan view. In one example, each capacitor 421 has two long sides along the Y-axis direction and two short sides along the X-axis direction. The four capacitors 421 are spaced apart from each other and lined up in a row in the X-axis direction with their long sides adjacent to each other. Each capacitor 421 includes a first electrode 42A and a second electrode 42B. The first electrode 42A is provided at one end of the capacitor 421 in the Y-axis direction, and the second electrode 42B is provided at the other end of the capacitor 421 in the Y-axis direction.

[0031] 1, like drive circuit 40A, drive circuits 40B to 40H also include switching elements 412 to 418 configured similarly to switching element 411, and capacitors 422 to 428 configured similarly to capacitor 421. Like drive circuit 40A, drive circuit 40B also includes four capacitors 422. The same applies to capacitors 423 to 428 of the other drive circuits 40C to 40H.

[0032] [General Configuration of Protection Diodes] As shown in FIG. 1 , the semiconductor light-emitting device 10 includes, in addition to the plurality of semiconductor light-emitting elements 30A-30H and the plurality of drive circuits 40A-40H described above, a plurality of (e.g., eight in FIG. 1 ) protection diodes 70A-70H that protect the plurality of semiconductor light-emitting elements 30A-30H mounted on the semiconductor light-emitting device 10. The protection diodes 70A-70H are provided corresponding to the semiconductor light-emitting elements 30A-30H. The protection diodes 70A-70H are provided, for example, for each channel (one of the drive circuits 40A-40H). Note that the configurations of the protection diodes 70A-70H are the same, so the following description will focus on the configuration of the protection diode 70A, and a detailed description of the configurations of the protection diodes 70B-70H will be omitted.

[0033] 3, the protection diode 70A is connected in anti-parallel to the semiconductor light emitting element 30A to be driven by the switching element 411 (drive circuit 40A). However, the number of semiconductor light emitting elements 30A connected to the protection diode 70A is not limited to one. The protection diode 70A may be connected in anti-parallel to one or more semiconductor light emitting elements provided per channel (drive circuit 40A).

[0034] The protection diode 70A has a rectangular shape having long and short sides in a plan view. The protection diode 70A is disposed so that the long sides are aligned along the X-axis direction and the short sides are aligned along the Y-axis direction. The protection diode 70A includes an anode electrode 71 and a cathode electrode 72 provided at both ends of the long sides.

[0035] [Electrode Layers of the Substrate] Next, the configuration of the multiple electrode layers of the substrate 20, i.e., the first to fourth electrode layers 28A to 28D, will be described. As shown in FIG. 7 , the first electrode layer 28A is provided as a front electrode layer on the first substrate surface 21 of the substrate 20. The second electrode layer 28B is provided as a back electrode layer on the second substrate surface 22 of the substrate 20. The third electrode layer 28C and the fourth electrode layer 28D are each provided as intermediate electrode layers located between the first electrode layer 28A and the second electrode layer 28B in the thickness direction (Z-axis direction) of the substrate 20. The third electrode layer 28C is provided as a front-side intermediate electrode layer located closer to the first electrode layer 28A (front electrode layer). The fourth electrode layer 28D is provided as a back-side intermediate electrode layer located closer to the second electrode layer 28B (back electrode layer).

[0036] 3 to 6 , the first electrode layer 28A (surface electrode layer) provided on the first substrate surface 21 of the substrate 20 includes a plurality of surface electrodes (pattern electrodes) spaced apart from one another. In the first embodiment, the first electrode layer 28A includes first surface electrodes 61A to 61H, second surface electrodes 62A to 62H, third surface electrodes 63A to 63H, a fourth surface electrode 64, fifth surface electrodes 65A to 65H, and sixth surface electrodes 66A to 66H. Here, in the first embodiment, the first surface electrodes 61A to 61H are an example of "surface-side cathode electrodes," and the second surface electrodes 62A to 62H are an example of "surface-side anode electrodes."

[0037] The first surface electrodes 61A-61H and the second surface electrodes 62A-62H are used to mount multiple semiconductor light emitting elements 30A-30H. In the first embodiment, each of the first surface electrodes 61A-61H and the second surface electrodes 62A-62H is mounted with a corresponding one of the semiconductor light emitting elements 30A-30H. The second surface electrodes 62A-62H, the third surface electrodes 63A-63H, the fourth surface electrode 64, the fifth surface electrodes 65A-65H, and the sixth surface electrodes 66A-66H are used to mount multiple drive circuits 40A-40H. In this way, the second surface electrodes 62A-62H are shared by the semiconductor light emitting elements 30A-30H and the drive circuits 40A-40H.

[0038] As shown in FIG. 2, the first surface electrodes 61A-61H and the second surface electrodes 62A-62H are located in a central region AC of the substrate 20. As shown in FIGS. 3 to 6, the surface electrodes other than the first surface electrodes 61A-61H and the second surface electrodes 62A-62H, i.e., the third surface electrodes 63A-63H, the fourth surface electrode 64, the fifth surface electrodes 65A-65H, and the sixth surface electrodes 66A-66H, are provided in a peripheral region AP of the substrate 20, which is located outside the first surface electrodes 61A-61H in a planar view. Furthermore, portions of the second surface electrodes 62A-62H are also provided in the peripheral region AP of the substrate 20. As shown in FIG. 1, the fourth surface electrode 64 is annular in a planar view, surrounding the first surface electrodes 61A-61H, the second surface electrodes 62A-62H, and the third surface electrodes 63A-63H (see FIGS. 3 to 6 for all of these). As used herein, the term "annular" can refer to any configuration that forms a loop, or to continuous shapes with no ends, as well as generally looped configurations with gaps, such as C-shapes. "Annular" shapes include, but are not limited to, circles, ellipses, and polygons with sharp or rounded corners.

[0039] As shown in FIG. 2, the first surface electrodes 61A to 61H and the second surface electrodes 62A to 62H are collectively arranged in a central region AC of the substrate 20. In the first embodiment, the first surface electrodes 61A to 61D are arranged in a row in the X-axis direction, and the remaining first surface electrodes 61E to 61H are arranged in a row in the X-axis direction and adjacent to the first surface electrodes 61A to 61D in the Y-axis direction. Therefore, the first surface electrodes 61A to 61H are arranged in a matrix adjacent to each other in the central region AC of the substrate 20. In one example, each of the first surface electrodes 61A to 61H has a circular opening in a plan view. The second surface electrodes 62A to 62H are provided in the openings of the corresponding first surface electrodes 61A to 61H. The second surface electrodes 62A to 62H are circular in a plan view. As shown in Figures 3 to 6, each of the first surface electrodes 61A to 61H includes a central electrode pattern PA provided in a central region AC and a peripheral electrode pattern PB provided in a peripheral region AP. The central electrode pattern PA of each of the first surface electrodes 61A to 61H is a portion that surrounds the corresponding second surface electrode 62A to 62H in a plan view. The peripheral electrode pattern PB of each of the first surface electrodes 61A to 61H is a portion that extends toward the corresponding drive circuit 40A to 40H. The peripheral electrode pattern PB is generally T-shaped in a plan view. The shape of the peripheral electrode pattern PB in a plan view can be changed as desired.

[0040] As shown in FIG. 2, the semiconductor light emitting elements 30A-30H are mounted on the central electrode patterns PA (see FIGS. 3-6) and second surface electrodes 62A-62H of the corresponding first surface electrodes 61A-61H. Therefore, the semiconductor light emitting elements 30A-30H can be said to be mounted in a central region AC. As shown in FIG. 3, the semiconductor light emitting element 30A is mounted on the central electrode pattern PA and second surface electrode 62A of the first surface electrode 61A using a submount substrate 50 (described later). The cathode electrode 35 of the semiconductor light emitting element 30A is electrically connected to the first surface electrode 61A. The anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the second surface electrode 62A. Similarly, the corresponding semiconductor light emitting elements 30B-30H are mounted on the central electrode patterns PA and second surface electrodes 62B-62H of the other first surface electrodes 61B-61H.

[0041] As shown in Figures 3 to 6, the first surface electrodes 61A to 61H, the second surface electrodes 62A to 62H, the third surface electrodes 63A to 63H, the fourth surface electrode 64, the fifth surface electrodes 65A to 65H, and the sixth surface electrodes 66A to 66H are arranged in a rotationally symmetric relationship within the substrate 20.

[0042] As shown in FIG. 1 , the first substrate surface 21 of the substrate 20 includes four wiring (electrode) arrangement regions divided based on an imaginary center line VC extending in the Y-axis direction at the center of the substrate 20 in the X-axis direction and an imaginary center line HC extending in the X-axis direction at the center of the substrate 20 in the Y-axis direction. These regions include a first partitioned region SP1, a second partitioned region SP2, a third partitioned region SP3, and a fourth partitioned region SP4, which correspond to the lower right region, lower left region, upper right region, and upper left region of the substrate 20, respectively, in FIG. Each of the first to fourth partitioned regions SP1 to SP4 includes a portion of the central region AC and a portion of the peripheral region AP. The surface electrode layouts within the first to fourth partitioned regions SP1 to SP4 will be described below.

[0043] 3 , central electrode patterns PA of the first surface electrodes 61A and 61B and second surface electrodes 62A and 62B are arranged in a central region AC corresponding to the first partition region SP1. The central electrode pattern PA of the first surface electrode 61A and the second surface electrode 62A are used to mount the semiconductor light emitting element 30A using the submount substrate 50. The central electrode pattern PA of the first surface electrode 61B and the second surface electrode 62B are used to mount the semiconductor light emitting element 30B using the submount substrate 50.

[0044] In the first partition region SP1, the peripheral electrode patterns PB of the first surface electrodes 61A, 61B, the third surface electrodes 63A, 63B, part of the fourth surface electrode 64, the fifth surface electrodes 65A, 65B, and the sixth surface electrodes 66A, 66B are arranged.

[0045] The first surface electrode 61A and the third to fifth surface electrodes 63A, 64, and 65A are used to mount the drive circuit 40A. The first surface electrode 61B and the third to fifth surface electrodes 63B, 64, and 65B are used to mount the drive circuit 40B. The fifth surface electrode 65A and the sixth surface electrode 66A are used to mount the protection diode 70A. The fifth surface electrode 65B and the sixth surface electrode 66B are used to mount the protection diode 70B.

[0046] Therefore, the fourth surface electrode 64 in the first divided region SP1 is shared by the mounting of the drive circuits 40A and 40B. In this manner, the first divided region SP1 is allocated for mounting the two semiconductor light emitting elements 30A and 30B, the two drive circuits 40A and 40B, and the two protection diodes 70A and 70B.

[0047] The peripheral electrode pattern PB of the first surface electrode 61A extends in the Y-axis direction from the central electrode pattern PA of the first surface electrode 61A. The fourth surface electrode 64 includes a notched recess for arranging the peripheral electrode pattern PB of the first surface electrode 61A and the third surface electrode 63A. The third surface electrode 63A is arranged in a position adjacent in the X-axis direction to the tip end in the Y-axis direction of the peripheral electrode pattern PB of the first surface electrode 61A.

[0048] The fifth surface electrode 65A is disposed at a distance in the Y-axis direction from the first surface electrode 61A via the fourth surface electrode 64. The sixth surface electrode 66A is disposed adjacent to the fifth surface electrode 65A in the X-axis direction. Both the fifth surface electrode 65A and the sixth surface electrode 66A are disposed adjacent to the first side surface 23 in the Y-axis direction in a plan view.

[0049] The switching element 411 of the drive circuit 40A is mounted on the peripheral electrode pattern PB of the first surface electrode 61A. The drain electrode 41D (see FIG. 7) of the switching element 411 is joined to the peripheral electrode pattern PB of the first surface electrode 61A with a conductive bonding material SD (see FIG. 7). As a result, the drain electrode 41D of the switching element 411 is electrically connected to the cathode electrode 35 (see FIG. 14) of the semiconductor light emitting element 30A through the first surface electrode 61A and the submount substrate 50.

[0050] Each of the multiple source electrodes 41S of the switching element 411 is joined to the fourth surface electrode 64 by a conductive bonding material (not shown). The gate electrode 41G of the switching element 411 is joined to the third surface electrode 63A by a conductive bonding material (not shown). In this manner, the switching element 411 is disposed apart from the semiconductor light emitting element 30A in the Y-axis direction. The switching element 411 is disposed at a position overlapping with the semiconductor light emitting element 30A when viewed from the Y-axis direction.

[0051] The four capacitors 421 of the drive circuit 40A are mounted across both the fourth surface electrode 64 and the fifth surface electrode 65A. The first electrode 42A of each capacitor 421 is joined to the fourth surface electrode 64 by a conductive bonding material SD (see FIG. 7 ). The second electrode 42B of each capacitor 421 is joined to the fifth surface electrode 65A by a conductive bonding material SD (see FIG. 7 ). The first electrode 42A and the second electrode 42B of each capacitor 421 are arranged in the same position in the X-axis direction and spaced apart from each other in the Y-axis direction. The four capacitors 421 are arranged side by side in the X-axis direction and in the same position in the Y-axis direction.

[0052] The four capacitors 421 are arranged on the opposite side of the switching element 411 from the semiconductor light emitting element 30A in the Y-axis direction. In other words, the switching element 411 is arranged between the semiconductor light emitting element 30A and the four capacitors 421 in the Y-axis direction. In one example, the switching element 411 is arranged closer to the four capacitors 421 in the Y-axis direction than the semiconductor light emitting element 30A. In other words, the distance between the switching element 411 and the semiconductor light emitting element 30A in the Y-axis direction is greater than the distance between the switching element 411 and the capacitors 421 in the Y-axis direction. When viewed from the Y-axis direction, at least one of the four capacitors 421 is arranged in a position overlapping both the switching element 411 and the semiconductor light emitting element 30A.

[0053] The protection diode 70A is mounted across both the fifth surface electrode 65A and the sixth surface electrode 66A. The anode electrode 71 is bonded to the sixth surface electrode 66A with a conductive bonding material (not shown). The cathode electrode 72 is bonded to the fifth surface electrode 65A with a conductive bonding material (not shown).

[0054] The protection diode 70A is disposed on the opposite side of the capacitors 421 from the switching element 411 in the Y-axis direction. The protection diode 70A is disposed at a position overlapping with the capacitor 421 that is closest to the sixth surface electrode 66A in the X-axis direction among the four capacitors 421 when viewed from the Y-axis direction. The protection diode 70A also includes portions that extend beyond the four capacitors 421 in the X-axis direction when viewed from the Y-axis direction. The anode electrode 71 is disposed at a position that does not overlap with the four capacitors 421 when viewed from the Y-axis direction.

[0055] The peripheral electrode pattern PB of the first surface electrode 61B extends in the X-axis direction from the central electrode pattern PA of the first surface electrode 61B. The fourth surface electrode 64 includes a notched recess for arranging the peripheral electrode pattern PB of the first surface electrode 61B and the third surface electrode 63B. The third surface electrode 63B is arranged adjacent to the peripheral electrode pattern PB of the first surface electrode 61B in the X-axis direction and the Y-axis direction.

[0056] The fifth surface electrode 65B is disposed at a distance in the X-axis direction from the first surface electrode 61B via the fourth surface electrode 64. The sixth surface electrode 66B is disposed adjacent to the fifth surface electrode 65B in the Y-axis direction. Both the fifth surface electrode 65B and the sixth surface electrode 66B are disposed adjacent to the fourth side surface 26 in the X-axis direction in a plan view.

[0057] The switching element 412 of the drive circuit 40B is mounted on the peripheral electrode pattern PB of the first surface electrode 61B. The drain electrode 41D of the switching element 412 is joined to the peripheral electrode pattern PB of the first surface electrode 61B with a conductive bonding material (not shown). The cathode electrode 35 of the semiconductor light emitting element 30B is electrically connected to the central electrode pattern PA of the first surface electrode 61B using the submount substrate 50. Therefore, the drain electrode 41D of the switching element 412 is electrically connected to the cathode electrode 35 of the semiconductor light emitting element 30B through the first surface electrode 61B and the submount substrate 50.

[0058] Each of the multiple source electrodes 41S of the switching element 412 is joined to the fourth surface electrode 64 by a conductive bonding material (not shown). The gate electrode 41G of the switching element 412 is joined to the third surface electrode 63B by a conductive bonding material (not shown). In this manner, the switching element 412 is disposed apart from the semiconductor light emitting element 30B in the X-axis direction. The switching element 412 is disposed at a position overlapping with the semiconductor light emitting element 30B when viewed from the X-axis direction.

[0059] The four capacitors 422 of the drive circuit 40B are mounted across both the fourth surface electrode 64 and the fifth surface electrode 65B. The first electrode 42A of each capacitor 422 is joined to the fourth surface electrode 64 by a conductive bonding material (not shown), and the second electrode 42B of each capacitor 422 is joined to the fifth surface electrode 65B by a conductive bonding material (not shown). The first electrode 42A and the second electrode 42B of each capacitor 422 are arranged in the same position in the Y-axis direction and spaced apart from each other in the X-axis direction. The four capacitors 422 are arranged in the same position in the X-axis direction and side by side in the Y-axis direction.

[0060] The four capacitors 422 are arranged on the opposite side of the switching element 412 from the semiconductor light emitting element 30B in the X-axis direction. In other words, the switching element 412 is arranged between the semiconductor light emitting element 30B and the four capacitors 422 in the X-axis direction. In one example, the switching element 412 is arranged closer to the four capacitors 422 in the X-axis direction than the semiconductor light emitting element 30B. In other words, the distance between the switching element 412 and the semiconductor light emitting element 30B in the X-axis direction is greater than the distance between the switching element 412 and the capacitors 422 in the X-axis direction. At least one of the four capacitors 422 is arranged in a position overlapping both the semiconductor light emitting element 30B and the switching element 412 when viewed from the X-axis direction.

[0061] The protection diode 70B is mounted across both the fifth surface electrode 65B and the sixth surface electrode 66B. The anode electrode 71 of the protection diode 70B is joined to the sixth surface electrode 66B by a conductive bonding material (not shown). The cathode electrode 72 is joined to the fifth surface electrode 65B by a conductive bonding material (not shown).

[0062] The protection diode 70B is disposed on the opposite side of the capacitors 422 from the switching element 412 in the X-axis direction. The protection diode 70B is disposed in a position overlapping with the capacitor 422 that is closest to the sixth surface electrode 66B in the Y-axis direction among the four capacitors 422 when viewed from the X-axis direction. The protection diode 70B also includes a portion that protrudes in the Y-axis direction from the four capacitors 422 when viewed from the X-axis direction. The anode electrode 71 is disposed in a position that does not overlap with the four capacitors 422 when viewed from the X-axis direction. The anode electrode 71 is disposed in a position that overlaps with the switching element 411 of the drive circuit 40A when viewed from the X-axis direction.

[0063] 4, in a central region AC corresponding to the second partition region SP2 (the lower left region in FIG. 1), central electrode patterns PA of the first surface electrodes 61C and 61D and second surface electrodes 62C and 62D are arranged. The central electrode pattern PA of the first surface electrode 61C and the second surface electrode 62C are used to mount the semiconductor light emitting element 30C. The central electrode pattern PA of the first surface electrode 61D and the second surface electrode 62D are used to mount the semiconductor light emitting element 30D.

[0064] In the second partition region SP2, the peripheral electrode patterns PB of the first surface electrodes 61C, 61D, the third surface electrodes 63C, 63D, part of the fourth surface electrode 64, the fifth surface electrodes 65C, 65D, and the sixth surface electrodes 66C, 66D are arranged.

[0065] The first surface electrode 61C and the third to fifth surface electrodes 63C, 64, and 65C are used to mount the drive circuit 40C. The first surface electrode 61D and the third to fifth surface electrodes 63D, 64, and 65D are used to mount the drive circuit 40D. The fifth surface electrode 65C and the sixth surface electrode 66C are used to mount the protection diode 70C. The fifth surface electrode 65D and the sixth surface electrode 66D are used to mount the protection diode 70D.

[0066] Therefore, the fourth surface electrode 64 in the second divided region SP2 is shared for mounting the drive circuits 40C and 40D. In this manner, the second divided region SP2 is allocated for mounting the two semiconductor light emitting elements 30C and 30D, the two drive circuits 40C and 40D, and the two protection diodes 70C and 70D.

[0067] The surface electrodes and the elements mounted thereon arranged in the second partition region SP2 and the surface electrodes and the elements mounted thereon arranged in the first partition region SP1 are arranged in a rotationally symmetric relationship.

[0068] The first to third surface electrodes 61C, 62C, 63C, the fifth surface electrode 65C, and the sixth surface electrode 66C arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third surface electrodes 61B, 62B, 63B, the fifth surface electrode 65B, and the sixth surface electrode 66B (all of which are shown in FIG. 3 ) arranged in the first partition region SP1. Accordingly, the semiconductor light emitting element 30C, the switching element 413 and capacitor 423 of the drive circuit 40C, and the protection diode 70C are rotated 90° clockwise with respect to the semiconductor light emitting element 30B, the switching element 412 and capacitor 422 of the drive circuit 40B, and the protection diode 70B.

[0069] The first to third surface electrodes 61D, 62D, 63D, the fifth surface electrode 65D, and the sixth surface electrode 66D arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third surface electrodes 61A, 62A, 63A, the fifth surface electrode 65A, and the sixth surface electrode 66A (all of which are shown in FIG. 3 ) arranged in the first partition region SP1. Accordingly, the semiconductor light emitting element 30D, the switching element 414 and the capacitor 424 of the drive circuit 40D, and the protection diode 70D are rotated 90° clockwise with respect to the semiconductor light emitting element 30A, the switching element 411 and the capacitor 421 of the drive circuit 40A, and the protection diode 70A.

[0070] The fourth surface electrode 64 in the second partition region SP2 and the fourth surface electrode 64 in the first partition region SP1 are generally symmetrical with respect to the imaginary center line VC. On the other hand, a part of the fourth surface electrode 64 in the second partition region SP2 has a different shape from a part of the fourth surface electrode 64 in the first partition region SP1 because the positions of the third surface electrodes 63C and 63D are not symmetrical with respect to the imaginary center line VC with respect to the third surface electrodes 63A and 63B.

[0071] Due to the arrangement of the surface electrodes and elements described above, detailed explanations will be omitted regarding the arrangement of the first surface electrodes 61C, 61D, the second surface electrodes 62C, 62D, the third surface electrodes 63C, 63D, part of the fourth surface electrode 64, the fifth surface electrodes 65C, 65D, and the sixth surface electrodes 66C, 66D, as well as the semiconductor light-emitting elements 30C, 30D, the switching elements 413, 414 and capacitors 423, 424 of the drive circuits 40C, 40D mounted on these surface electrodes, and the protection diodes 70C, 70D.

[0072] 5, in a central region AC corresponding to the third partition region SP3 (the upper right region in FIG. 1), the central electrode patterns PA of the first surface electrodes 61E and 61F and the second surface electrodes 62E and 62F are arranged. The central electrode pattern PA of the first surface electrode 61E and the second surface electrode 62E are used to mount the semiconductor light emitting element 30E. The central electrode pattern PA of the first surface electrode 61F and the second surface electrode 62F are used to mount the semiconductor light emitting element 30F.

[0073] In the third partition region SP3, the peripheral electrode patterns PB of the first surface electrodes 61E, 61F, the third surface electrodes 63E, 63F, part of the fourth surface electrode 64, the fifth surface electrodes 65E, 65F, and the sixth surface electrodes 66E, 66F are arranged.

[0074] The first surface electrode 61E and the third to fifth surface electrodes 63E, 64, and 65E are used to mount the drive circuit 40E. The first surface electrode 61F and the third to fifth surface electrodes 63F, 64, and 65F are used to mount the drive circuit 40F. The fifth surface electrode 65E and the sixth surface electrode 66E are used to mount the protection diode 70E. The fifth surface electrode 65F and the sixth surface electrode 66F are used to mount the protection diode 70F.

[0075] Therefore, the fourth surface electrode 64 in the third partition region SP3 is shared for mounting the drive circuits 40E and 40F. In this manner, the third partition region SP3 is allocated for mounting the two drive circuits 40E and 40F and the two protection diodes 70E and 70F.

[0076] The surface electrodes and the elements mounted thereon arranged in the third partition region SP3 and the surface electrodes and the elements mounted thereon arranged in the first partition region SP1 are arranged in a rotationally symmetric relationship.

[0077] The first to third surface electrodes 61E, 62E, 63E, the fifth surface electrode 65E, and the sixth surface electrode 66E arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third surface electrodes 61B, 62B, 63B, the fifth surface electrode 65B, and the sixth surface electrode 66B (all of which are shown in FIG. 3 ) arranged in the first partition region SP1. Accordingly, the semiconductor light emitting element 30E, the switching element 415 and capacitor 425 of the drive circuit 40E, and the protection diode 70E are rotated 90° counterclockwise with respect to the semiconductor light emitting element 30B, the switching element 412 and capacitor 422 of the drive circuit 40B, and the protection diode 70B.

[0078] The first to third surface electrodes 61F, 62F, 63F, the fifth surface electrode 65F, and the sixth surface electrode 66F arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third surface electrodes 61A, 62A, 63A, the fifth surface electrode 65A, and the sixth surface electrode 66A (all of which are shown in FIG. 3 ) arranged in the first partition region SP1. Accordingly, the semiconductor light emitting element 30F, the switching element 416 and capacitor 426 of the drive circuit 40F, and the protection diode 70F are rotated 90° counterclockwise with respect to the semiconductor light emitting element 30A, the switching element 411 and capacitor 421 of the drive circuit 40A, and the protection diode 70A.

[0079] For this reason, detailed explanations will be omitted regarding the arrangement of the first surface electrodes 61E, 61F, the second surface electrodes 62E, 62F, the third surface electrodes 63E, 63F, part of the fourth surface electrode 64, the fifth surface electrodes 65E, 65F, and the sixth surface electrodes 66E, 66F, as well as the semiconductor light-emitting elements 30E, 30F mounted on these surface electrodes, the switching elements 415, 416 and capacitors 425, 426 of the drive circuits 40E, 40F, and the protection diodes 70E, 70F.

[0080] 6, in a central region AC corresponding to the fourth partition region SP4 (the upper left region in FIG. 1), central electrode patterns PA of the first surface electrodes 61G, 61H and second surface electrodes 62G, 62H are arranged. The central electrode pattern PA of the first surface electrode 61G and the second surface electrode 62G are used to mount the semiconductor light emitting element 30G. The central electrode pattern PA of the first surface electrode 61H and the second surface electrode 62H are used to mount the semiconductor light emitting element 30H.

[0081] In the fourth partition region SP4, the peripheral electrode patterns PB of the first surface electrodes 61G, 61H, the third surface electrodes 63G, 63H, a part of the fourth surface electrode 64, the fifth surface electrodes 65G, 65H, and the sixth surface electrodes 66G, 66H are arranged.

[0082] The first surface electrode 61G and the third to fifth surface electrodes 63G, 64, and 65G are used to mount the drive circuit 40G. The first surface electrode 61H and the third to fifth surface electrodes 63H, 64, and 65H are used to mount the drive circuit 40H. The fifth surface electrode 65G and the sixth surface electrode 66G are used to mount the protection diode 70G. The fifth surface electrode 65H and the sixth surface electrode 66H are used to mount the protection diode 70H.

[0083] Therefore, the fourth surface electrode 64 in the fourth partition region SP4 is shared for mounting the drive circuits 40G and 40H. It can also be said that the fourth surface electrode 64 is shared for mounting the drive circuits 40A to 40H. In this way, the fourth partition region SP4 is allocated for mounting the two drive circuits 40G and 40H and the two protection diodes 70G and 70H.

[0084] The surface electrodes and the elements mounted thereon arranged in the fourth partition region SP4 and the surface electrodes and the elements mounted thereon arranged in the first partition region SP1 are arranged in a rotationally symmetric relationship.

[0085] The first to third surface electrodes 61G, 62G, 63G, the fifth surface electrode 65G, and the sixth surface electrode 66G arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third surface electrodes 61D, 62D, 63D, the fifth surface electrode 65D, and the sixth surface electrode 66D (all of which are shown in FIG. 4 ) arranged in the second partition region SP2. Accordingly, the semiconductor light emitting element 30G, the switching element 417 and capacitor 427 of the drive circuit 40G, and the protection diode 70G are rotated 90° clockwise with respect to the semiconductor light emitting element 30D, the switching element 414 and capacitor 424 of the drive circuit 40D, and the protection diode 70D.

[0086] The first to third surface electrodes 61H, 62H, 63H, the fifth surface electrode 65H, and the sixth surface electrode 66H arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third surface electrodes 61C, 62C, 63C, the fifth surface electrode 65C, and the sixth surface electrode 66C (all of which are shown in FIG. 4 ) arranged in the second partition region SP2. Accordingly, the semiconductor light emitting element 30H, the switching element 418 and capacitor 428 of the drive circuit 40H, and the protection diode 70H are rotated 90° clockwise with respect to the semiconductor light emitting element 30C, the switching element 413 and capacitor 423 of the drive circuit 40C, and the protection diode 70C.

[0087] For this reason, detailed explanations will be omitted regarding the arrangement of the first surface electrodes 61G, 61H, the second surface electrodes 62G, 62H, the third surface electrodes 63G, 63H, part of the fourth surface electrode 64, the fifth surface electrodes 65G, 65H, and the sixth surface electrodes 66G, 66H, as well as the semiconductor light-emitting elements 30G, 30H mounted on these surface electrodes, the switching elements 417, 418 and capacitors 427, 428 of the drive circuits 40G, 40H, and the protection diodes 70G, 70H.

[0088] 7, the main surface resist layer 29A includes a plurality of openings that expose portions of the first electrode layer 28A. The semiconductor light emitting elements 30A-30H, the components of the drive circuits 40A-40H, and the protection diodes 70A-70H are mounted on the portions of the first electrode layer 28A that are exposed by the openings in the main surface resist layer 29A. In FIGS. 1 to 6, the openings in the main surface resist layer 29A are indicated by two-dot chain lines.

[0089] [Second Electrode Layer (Back Electrode Layer)] As shown in FIG. 8 , the second electrode layer 28B (back electrode layer) located on the second substrate surface 22 (see FIG. 7 ) of the substrate 20 includes a plurality of spaced-apart back electrodes (patterned electrodes). These back electrodes function as external electrode terminals electrically connected to a circuit board (not shown) when the semiconductor light-emitting device 10 is mounted on the circuit board. In the first embodiment, the second electrode layer 28B includes first back electrodes 81A-81H, second back electrodes 82A-82H, third back electrodes 83A-83H, fourth back electrodes 84A-84D, fifth back electrodes 85A-85H, and sixth back electrodes 86A-86H. Note that FIG. 8 is a perspective view to facilitate understanding of the correspondence between the first electrode layer 28A, the third electrode layer 28C, and the fourth electrode layer 28D.

[0090] The first rear-surface electrodes 81A-81H, the second rear-surface electrodes 82A-82H, the third rear-surface electrodes 83A-83H, the fourth rear-surface electrodes 84A-84D, the fifth rear-surface electrodes 85A-85H, and the sixth rear-surface electrodes 86A-86H are arranged in a rotationally symmetric relationship. The second substrate surface 22 of the substrate 20 includes first to fourth partitioned regions SP1-SP4 as four wiring arrangement regions divided based on imaginary center lines VC and HC. When the substrate 20 is viewed from the second substrate surface 22, the first partitioned region SP1, the second partitioned region SP2, the third partitioned region SP3, and the fourth partitioned region SP4 correspond to the lower right region, lower left region, upper right region, and upper left region of the substrate 20, respectively, in FIG. 8. The rear-surface electrode layouts within the first to fourth partitioned regions SP1-SP4 will be described below.

[0091] In the first partition region SP1 (the lower right region in Figure 8), first back surface electrodes 81A, 81B, second back surface electrodes 82A, 82B, third back surface electrodes 83A, 83B, fourth back surface electrode 84A, fifth back surface electrodes 85A, 85B, and sixth back surface electrodes 86A, 86B are arranged.

[0092] The first to sixth rear surface electrodes 81A to 86A are provided for electrical connection between the switching element 411 and capacitor 421 of the drive circuit 40A shown in FIG. 3, the semiconductor light emitting element 30A to be driven by the drive circuit 40A, and the protection diode 70A.

[0093] The first back surface electrode 81A is arranged in a position overlapping the second surface electrode 62A and the fifth surface electrode 65A (see FIG. 3 ) in a plan view. The first back surface electrode 81A has, for example, a strip shape extending in the Y-axis direction. The second back surface electrode 82A is arranged in a position overlapping the peripheral electrode pattern PB (see FIG. 3 ) of the first surface electrode 61A in a plan view. The second back surface electrode 82A has, for example, an oval shape in a plan view. The second back surface electrode 82A is arranged adjacent to or close to the first back surface electrode 81A in the X-axis direction. The second back surface electrode 82A is arranged adjacent to or close to the first back surface electrode 81B in the Y-axis direction.

[0094] The third back surface electrode 83A is disposed at a position overlapping the third front surface electrode 63A (see FIG. 3 ) in a plan view. The third back surface electrode 83A is provided, for example, in a curved strip shape with a dimension shorter in the Y-axis direction than the first back surface electrode 81A. The third back surface electrode 83A extends to a position adjacent to the first side surface 23 in the Y-axis direction in a plan view. The third back surface electrode 83A includes a portion provided adjacent to or close to the first back surface electrode 81A in the X-axis direction and a portion provided adjacent to or close to the fourth back surface electrode 84A in the X-axis direction.

[0095] The fourth back surface electrode 84A is disposed in a position that overlaps with a part of the fourth front surface electrode 64 in the first divided region SP1 in a plan view. The fourth back surface electrode 84A is disposed in a corner portion of the second substrate surface 22 of the substrate 20 in the first divided region SP1.

[0096] The fifth back surface electrode 85A is disposed in a position overlapping with a portion of the fourth front surface electrode 64 (see FIG. 3 ) in the first partition region SP1 in a plan view. The fifth back surface electrode 85A has, for example, a circular shape in a plan view. The fifth back surface electrode 85A is disposed adjacent to or close to the first back surface electrode 81A in the X-axis direction and adjacent to or close to the second back surface electrode 82A in the Y-axis direction.

[0097] The sixth back surface electrode 86A is disposed at a position overlapping the sixth front surface electrode 66A (see FIG. 3) in a plan view. The sixth back surface electrode 86A has, for example, a rectangular shape with its long sides extending in the Y-axis direction and its short sides extending in the X-axis direction in a plan view. The sixth back surface electrode 86A is disposed between the end of the first back surface electrode 81A in the Y-axis direction and the end of the third back surface electrode 83A in the Y-axis direction in the X-axis direction. The sixth back surface electrode 86A is disposed at a position adjacent to the first side surface 23 in the Y-axis direction in a plan view.

[0098] The first to sixth back electrodes 81B, 82B, 83B, 84A, 85B, and 86B are provided for electrical connection between the switching element 412 and capacitor 422 of the drive circuit 40B shown in FIG. 3, the semiconductor light-emitting element 30B to be driven by the drive circuit 40B, and the protection diode 70B.

[0099] The first back surface electrode 81B is arranged in a position overlapping the second surface electrode 62B and the fifth surface electrode 65B (see FIG. 3) in a plan view. The first back surface electrode 81B has, for example, a strip shape extending in the X-axis direction. The second back surface electrode 82B is arranged in a position overlapping the peripheral electrode pattern PB of the first surface electrode 61B in a plan view. The second back surface electrode 82B has, for example, an oval shape in a plan view. The second back surface electrode 82B is provided adjacent to or close to the first back surface electrode 81B in the Y-axis direction.

[0100] The third back surface electrode 83B is disposed at a position overlapping the third front surface electrode 63B (see FIG. 3 ) in a plan view. The third back surface electrode 83B is provided, for example, in a curved strip shape with a dimension shorter in the X-axis direction than the first back surface electrode 81B. The third back surface electrode 83B extends to a position adjacent to the fourth side surface 26 in the X-axis direction in a plan view. The third back surface electrode 83B includes a portion provided adjacent to or close to the first back surface electrode 81B in the Y-axis direction and a portion provided adjacent to or close to the fourth back surface electrode 84A in the Y-axis direction.

[0101] The fifth back surface electrode 85B is disposed in a position overlapping with a portion of the fourth surface electrode 64 (see FIG. 3 ) in the first partition region SP1 in a plan view. The fifth back surface electrode 85B has, for example, a circular shape in a plan view. The fifth back surface electrode 85B is disposed adjacent to or close to the first back surface electrode 81B in the Y-axis direction and spaced apart from the second back surface electrode 82B in the X-axis direction. Of both end portions of the third back surface electrode 83B in the X-axis direction, the end portion farther from the fourth side surface 26 is disposed between the second back surface electrode 82B and the fifth back surface electrode 85B in the X-axis direction.

[0102] The sixth back surface electrode 86B is disposed at a position overlapping with the sixth front surface electrode 66B (see FIG. 3) in a plan view. The sixth back surface electrode 86B has, for example, a rectangular shape with its long sides in the X-axis direction and its short sides in the Y-axis direction in a plan view. The sixth back surface electrode 86B is provided between the end of the first back surface electrode 81B in the X-axis direction and the end of the third back surface electrode 83B in the X-axis direction in the Y-axis direction. The sixth back surface electrode 86B is disposed at a position adjacent to the fourth side surface 26 in the X-axis direction in a plan view.

[0103] In the second partition region SP2 (the lower left region in Figure 8), first back surface electrodes 81C, 81D, second back surface electrodes 82C, 82D, third back surface electrodes 83C, 83D, fourth back surface electrode 84B, fifth back surface electrodes 85C, 85D, and sixth back surface electrodes 86C, 86D are arranged.

[0104] 4, the semiconductor light emitting element 30C to be driven by the drive circuit 40C, and the protection diode 70C. The first to sixth back surface electrodes 81C, 82C, 83C, 84B, 85C, and 86C are provided for electrically connecting the switching element 413 and capacitor 423 of the drive circuit 40C, the semiconductor light emitting element 30C to be driven by the drive circuit 40C, and the protection diode 70C. The first to sixth back surface electrodes 81D, 82D, 83D, 84B, 85D, and 86D are provided for electrically connecting the switching element 414 and capacitor 424 of the drive circuit 40D, the semiconductor light emitting element 30D to be driven by the drive circuit 40D, and the protection diode 70D.

[0105] 8 , the first to third back-surface electrodes 81C, 82C, 83C and the fifth and sixth back-surface electrodes 85C, 86C arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third back-surface electrodes 81B, 82B, 83B, the fifth back-surface electrode 85B, and the sixth back-surface electrode 86B arranged in the first partition region SP1. The first to third back-surface electrodes 81D, 82D, 83D and the fifth and sixth back-surface electrodes 85D, 86D arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third back-surface electrodes 81A, 82A, 83A and the fifth and sixth back-surface electrodes 85A, 86A arranged in the first partition region SP1. The fourth back-surface electrode 84B and the fourth back-surface electrode 84A are axisymmetric with respect to the virtual center line VC. Therefore, detailed explanations of the arrangement of the first back surface electrodes 81C, 81D, second back surface electrodes 82C, 82D, third back surface electrodes 83C, 83D, fourth back surface electrode 84B, fifth back surface electrodes 85C, 85D, and sixth back surface electrodes 86C, 86D will be omitted.

[0106] In the third partition region SP3 (the upper right region in Figure 8), first back surface electrodes 81E, 81F, second back surface electrodes 82E, 82F, third back surface electrodes 83E, 83F, fourth back surface electrode 84C, fifth back surface electrodes 85E, 85F, and sixth back surface electrodes 86E, 86F are arranged.

[0107] 5, the semiconductor light emitting element 30E to be driven by the drive circuit 40E, and the protection diode 70E. The first to sixth back surface electrodes 81E, 82E, 83E, 84C, 85E, and 86E are provided for electrically connecting the switching element 415 and capacitor 425 of the drive circuit 40E, the semiconductor light emitting element 30E to be driven by the drive circuit 40E, and the protection diode 70E. The first to sixth back surface electrodes 81F, 82F, 83F, 84C, 85F, and 86F are provided for electrically connecting the switching element 416 and capacitor 426 of the drive circuit 40F, the semiconductor light emitting element 30F to be driven by the drive circuit 40F, and the protection diode 70F.

[0108] 8 , the first to third back-surface electrodes 81E, 82E, 83E, the fifth back-surface electrode 85E, and the sixth back-surface electrode 86E arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third back-surface electrodes 81B, 82B, 83B, the fifth back-surface electrode 85B, and the sixth back-surface electrode 86B arranged in the first partition region SP1. The first to third back-surface electrodes 81F, 82F, 83F, the fifth back-surface electrode 85F, and the sixth back-surface electrode 86F arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third back-surface electrodes 81A, 82A, 83A, the fifth back-surface electrode 85A, and the sixth back-surface electrode 86A arranged in the first partition region SP1. The fourth back-surface electrode 84C and the fourth back-surface electrode 84A are symmetrical with respect to the imaginary center line HC. Therefore, detailed explanations of the arrangement of the first back surface electrodes 81E, 81F, second back surface electrodes 82E, 82F, third back surface electrodes 83E, 83F, fourth back surface electrode 84C, fifth back surface electrodes 85E, 85F, and sixth back surface electrodes 86E, 86F will be omitted.

[0109] In the fourth partition region SP4 (upper left region in Figure 8), first back surface electrodes 81G, 81H, second back surface electrodes 82G, 82H, third back surface electrodes 83G, 83H, fourth back surface electrode 84D, fifth back surface electrodes 85G, 85H, and sixth back surface electrodes 86G, 86H are arranged.

[0110] 6, the semiconductor light emitting element 30G to be driven by the drive circuit 40G, and the protection diode 70G. The first to sixth back surface electrodes 81G, 82G, 83G, 84D, 85G, and 86G are provided for electrically connecting the switching element 417 and capacitor 427 of the drive circuit 40G, the semiconductor light emitting element 30G to be driven by the drive circuit 40G, and the protection diode 70G. The first to sixth back surface electrodes 81H, 82H, 83H, 84D, 85H, and 86H are provided for electrically connecting the switching element 418 and capacitor 428 of the drive circuit 40H, the semiconductor light emitting element 30H to be driven by the drive circuit 40H, and the protection diode 70H.

[0111] 8 , the first to third back-surface electrodes 81G, 82G, 83G, the fifth back-surface electrode 85G, and the sixth back-surface electrode 86G arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third back-surface electrodes 81D, 82D, 83D, the fifth back-surface electrode 85D, and the sixth back-surface electrode 86D arranged in the second partition region SP2. The first to third back-surface electrodes 81H, 82H, 83H, the fifth back-surface electrode 85H, and the sixth back-surface electrode 86H arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third back-surface electrodes 81C, 82C, 83C, the fifth back-surface electrode 85C, and the sixth back-surface electrode 86C arranged in the second partition region SP2. The fourth back-surface electrode 84D and the fourth back-surface electrode 84B are axisymmetric with respect to the imaginary center line HC. Therefore, detailed explanations of the arrangement of the first back surface electrodes 81G, 81H, the second back surface electrodes 82G, 82H, the third back surface electrodes 83G, 83H, the fourth back surface electrode 84D, the fifth back surface electrodes 85G, 85H, and the sixth back surface electrodes 86G, 86H will be omitted.

[0112] As shown in Fig. 7, the back surface resist layer 29B includes a plurality of openings that expose portions of the second electrode layer 28B. The semiconductor light emitting device 10 is mounted on a circuit board (not shown) using the portions of the second electrode layer 28B exposed by the openings in the back surface resist layer 29B. Therefore, the semiconductor light emitting device 10 can be said to be a surface-mounted device mounted on a circuit board. In Fig. 8, the openings in the back surface resist layer 29B are indicated by two-dot chain lines.

[0113] 7 , the third electrode layer 28C and the fourth electrode layer 28D, which are intermediate electrode layers, are embedded in the substrate 20. The third electrode layer 28C provided as the front-side intermediate electrode layer is located between the first substrate 27A including the first substrate surface 21 of the substrate 20 and the third substrate 27C located midway in the thickness direction (Z-axis direction) of the substrate 20. On the other hand, the fourth electrode layer 28D provided as the back-side intermediate electrode layer is located between the second substrate 27B including the second substrate surface 22 of the substrate 20 and the third substrate 27C.

[0114] 9, the third electrode layer 28C includes a plurality of intermediate electrodes (pattern electrodes) spaced apart from one another. In the first embodiment, the third electrode layer 28C includes first intermediate electrodes 91A to 91H, second intermediate electrodes 92A to 92H, third intermediate electrodes 93A to 93H, fourth intermediate electrodes 94A to 94D, and fifth intermediate electrodes 95A to 95H.

[0115] The first intermediate electrodes 91A-91H, second intermediate electrodes 92A-92H, third intermediate electrodes 93A-93H, fourth intermediate electrodes 94A-94D, and fifth intermediate electrodes 95A-95H are arranged in a rotationally symmetric relationship. The third base material 27C includes first to fourth partitioned regions SP1-SP4 as four wiring arrangement regions divided based on imaginary center lines VC and HC. The first partitioned region SP1, second partitioned region SP2, third partitioned region SP3, and fourth partitioned region SP4 correspond to the lower right region, lower left region, upper right region, and upper left region of the substrate 20, respectively, in FIG. 9. The layout of the intermediate electrodes within the first to fourth partitioned regions SP1-SP4 will be described below.

[0116] In the first partition region SP1 (the lower right region in Figure 9), first intermediate electrodes 91A, 91B, second intermediate electrodes 92A, 92B, third intermediate electrodes 93A, 93B, fourth intermediate electrode 94A, and fifth intermediate electrodes 95A, 95B are arranged.

[0117] The first to fifth intermediate electrodes 91A, 92A, 93A, 94A, and 95A are provided for electrically connecting the switching element 411 and capacitor 421 of the drive circuit 40A shown in Figure 3, the semiconductor light-emitting element 30A to be driven by the drive circuit 40A, and the protection diode 70A.

[0118] 9, the first intermediate electrode 91A is elongated in the Y-axis direction in plan view and is disposed at a position overlapping the second surface electrode 62A and the fifth surface electrode 65A (both see FIG. 3) and the first back surface electrode 81A (see FIG. 8) in plan view.

[0119] The second intermediate electrode 92A is disposed at a position overlapping the first surface electrode 61A and the sixth surface electrode 66A (see FIG. 3 ) and the second back surface electrode 82A and the sixth back surface electrode 86A (see FIG. 8 ) in a plan view. The second intermediate electrode 92A is, for example, a curved strip-shaped electrode that is shorter in the Y-axis direction than the first intermediate electrode 91A. The second intermediate electrode 92A extends to a position adjacent to the first side surface 23 in the Y-axis direction in a plan view. The second intermediate electrode 92A is disposed adjacent to or close to the first intermediate electrode 91A in the X-axis direction.

[0120] The third intermediate electrode 93A is disposed at a position overlapping the third front surface electrode 63A (see FIG. 3 ) and the third back surface electrode 83A (see FIG. 8 ) in a plan view. The third intermediate electrode 93A has, for example, a circular shape in a plan view. The third intermediate electrode 93A is disposed between the first intermediate electrode 91A and the second intermediate electrode 92A in the X-axis direction in a plan view.

[0121] The fourth intermediate electrode 94A is disposed in a position that overlaps with a portion of the fourth front surface electrode 64 (see FIG. 3) in the first partition region SP1 and also overlaps with the fourth back surface electrode 84A (see FIG. 8) in a plan view. The fourth intermediate electrode 94A can also be said to be disposed in a corner portion of the third base material 27C in a plan view. The fourth intermediate electrode 94A has, for example, a rectangular shape in a plan view.

[0122] The fifth intermediate electrode 95A is disposed at a position overlapping the fourth surface electrode 64 (see FIG. 3) and the fifth back surface electrode 85A (see FIG. 8) in a plan view. The fifth intermediate electrode 95A is, for example, circular in a plan view. The fifth intermediate electrode 95A is disposed, for example, between the first intermediate electrode 91A and the second intermediate electrode 92A in the X-axis direction in a plan view. The fifth intermediate electrode 95A is disposed, for example, between the second intermediate electrode 92A and the third intermediate electrode 93A in the Y-axis direction in a plan view.

[0123] The first to fifth intermediate electrodes 91B, 92B, 93B, 94A, and 95B are provided for electrically connecting the switching element 412 and capacitor 422 of the drive circuit 40B shown in Figure 3, the semiconductor light-emitting element 30B to be driven by the drive circuit 40B, and the protection diode 70B.

[0124] 9, the first intermediate electrode 91B is elongated in the X-axis direction in plan view and is disposed at a position overlapping the second surface electrode 62B and the fifth surface electrode 65B (see FIG. 3) and the first back surface electrode 81B (see FIG. 8) in plan view.

[0125] The second intermediate electrode 92B is disposed in a position overlapping the first surface electrode 61B and the sixth surface electrode 66B (see FIG. 3 ) and the second back surface electrode 82B and the sixth back surface electrode 86B (see FIG. 8 ) in a plan view. The second intermediate electrode 92B is, for example, a curved strip-shaped electrode that is shorter in the X-axis direction than the first intermediate electrode 91A. The second intermediate electrode 92B extends to a position adjacent to the fourth side surface 26 in the X-axis direction in a plan view. The second intermediate electrode 92B is disposed adjacent to or close to the first intermediate electrode 91B in the Y-axis direction.

[0126] The third intermediate electrode 93B is disposed at a position overlapping the third front surface electrode 63B (see FIG. 3) and the third back surface electrode 83B (see FIG. 8) in a plan view. The third intermediate electrode 93B has, for example, a circular shape in a plan view. The third intermediate electrode 93B is disposed between the first intermediate electrode 91B and the second intermediate electrode 92B in the Y-axis direction in a plan view.

[0127] The fifth intermediate electrode 95B is disposed at a position overlapping the fourth surface electrode 64 (see FIG. 3) and the fifth back surface electrode 85B (see FIG. 8) in a plan view. The fifth intermediate electrode 95B has, for example, a circular shape in a plan view. The fifth intermediate electrode 95B is disposed, for example, between the first intermediate electrode 91B and the second intermediate electrode 92B in the Y-axis direction in a plan view. The fifth intermediate electrode 95B is disposed adjacent to or close to the third intermediate electrode 93B in the X-axis direction in a plan view.

[0128] In the second partition region SP2 (the lower left region in FIG. 9), first intermediate electrodes 91C and 91D, second intermediate electrodes 92C and 92D, third intermediate electrodes 93C and 93D, a fourth intermediate electrode 94B, and fifth intermediate electrodes 95C and 95D are arranged.

[0129] The first to fifth intermediate electrodes 91C, 92C, 93C, 94B, and 95C are provided for electrically connecting the switching element 413 and capacitor 423 of the drive circuit 40C shown in Fig. 4, the semiconductor light emitting element 30C to be driven by the drive circuit 40C, and the protection diode 70C. The first to fifth intermediate electrodes 91D, 92D, 93D, 94B, and 95D are provided for electrically connecting the switching element 414 and capacitor 424 of the drive circuit 40D, the semiconductor light emitting element 30D to be driven by the drive circuit 40D, and the protection diode 70D.

[0130] 9 , the first to third intermediate electrodes 91C, 92C, 93C and the fifth intermediate electrode 95C arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third intermediate electrodes 91B, 92B, 93B and the fifth intermediate electrode 95B arranged in the first partition region SP1. The first to third intermediate electrodes 91D, 92D, 93D and the fifth intermediate electrode 95D arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third intermediate electrodes 91A, 92A, 93A and the fifth intermediate electrode 95A arranged in the first partition region SP1. The fourth intermediate electrode 94B and the fourth intermediate electrode 94A are symmetrical with respect to the virtual center line VC. Therefore, detailed description of the arrangement of the first intermediate electrodes 91C, 91D, second intermediate electrodes 92C, 92D, third intermediate electrodes 93C, 93D, fourth intermediate electrode 94B, and fifth intermediate electrodes 95C, 95D will be omitted.

[0131] In the third partition region SP3 (the upper right region in FIG. 9), first intermediate electrodes 91E and 91F, second intermediate electrodes 92E and 92F, third intermediate electrodes 93E and 93F, a fourth intermediate electrode 94C, and fifth intermediate electrodes 95E and 95F are arranged.

[0132] 5, the semiconductor light emitting element 30E to be driven by the drive circuit 40E, and the protection diode 70E. The first to fifth intermediate electrodes 91F, 92F, 93F, 94C, and 95F are provided for electrically connecting the switching element 416 and capacitor 426 of the drive circuit 40F, the semiconductor light emitting element 30F to be driven by the drive circuit 40F, and the protection diode 70F.

[0133] 9 , the first to third intermediate electrodes 91E, 92E, 93E and the fifth intermediate electrode 95E arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third intermediate electrodes 91B, 92B, 93B and the fifth intermediate electrode 95B arranged in the first partition region SP1. The first to third intermediate electrodes 91F, 92F, 93F and the fifth intermediate electrode 95F arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third intermediate electrodes 91A, 92A, 93A and the fifth intermediate electrode 95A arranged in the first partition region SP1. The fourth intermediate electrode 94C and the fourth intermediate electrode 94A are symmetrical with respect to the imaginary center line HC. Therefore, detailed description of the arrangement of the first intermediate electrodes 91E, 91F, second intermediate electrodes 92E, 92F, third intermediate electrodes 93E, 93F, fourth intermediate electrode 94C, and fifth intermediate electrodes 95E, 95F will be omitted.

[0134] In the fourth partition region SP4 (upper left region in FIG. 9), first intermediate electrodes 91G, 91H, second intermediate electrodes 92G, 92H, third intermediate electrodes 93G, 93H, fourth intermediate electrode 94D, and fifth intermediate electrodes 95G, 95H are arranged.

[0135] 6, the semiconductor light emitting element 30G to be driven by the drive circuit 40G, and the protection diode 70G. The first to fifth intermediate electrodes 91H, 92H, 93H, 94D, and 95H are provided for electrically connecting the switching element 418 and capacitor 428 of the drive circuit 40H, the semiconductor light emitting element 30H to be driven by the drive circuit 40H, and the protection diode 70H.

[0136] 9 , the first to third intermediate electrodes 91G, 92G, 93G and the fifth intermediate electrode 95G arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third intermediate electrodes 91D, 92D, 93D and the fifth intermediate electrode 95D arranged in the second partition region SP2. The first to third intermediate electrodes 91H, 92H, 93H and the fifth intermediate electrode 95H arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third intermediate electrodes 91C, 92C, 93C and the fifth intermediate electrode 95C arranged in the second partition region SP2. The fourth intermediate electrode 94D and the fourth intermediate electrode 94B are symmetrical with respect to the imaginary center line HC. Therefore, detailed description of the arrangement of the first intermediate electrodes 91G, 91H, second intermediate electrodes 92G, 92H, third intermediate electrodes 93G, 93H, fourth intermediate electrode 94D, and fifth intermediate electrodes 95G, 95H will be omitted.

[0137] 10, the fourth electrode layer 28D includes a plurality of intermediate electrodes (pattern electrodes) spaced apart from one another. In the first embodiment, the fourth electrode layer 28D includes first intermediate electrodes 101A to 101H, second intermediate electrodes 102A to 102H, third intermediate electrodes 103A to 103H, fourth intermediate electrodes 104A to 104D, and fifth intermediate electrodes 105A to 105H.

[0138] The first intermediate electrodes 101A-101H, the second intermediate electrodes 102A-102H, the third intermediate electrodes 103A-103H, the fourth intermediate electrodes 104A-104D, and the fifth intermediate electrodes 105A-105H are arranged in a rotationally symmetric relationship. The second base material 27B includes first to fourth partitioned regions SP1-SP4 as four wiring arrangement regions divided based on imaginary center lines VC and HC. The first partitioned region SP1, the second partitioned region SP2, the third partitioned region SP3, and the fourth partitioned region SP4 correspond to the lower right region, lower left region, upper right region, and upper left region of the substrate 20 in FIG. 10, respectively. The layout of the intermediate electrodes within the first to fourth partitioned regions SP1-SP4 will be described below.

[0139] In the first partition region SP1 (the lower right region in FIG. 10), first intermediate electrodes 101A and 101B, second intermediate electrodes 102A and 102B, third intermediate electrodes 103A and 103B, fourth intermediate electrode 104A, and fifth intermediate electrodes 105A and 105B are arranged.

[0140] The first to fifth intermediate electrodes 101A, 102A, 103A, 104A, and 105A are provided for electrical connection between the switching element 411 and capacitor 421 of the drive circuit 40A shown in Figure 3, the semiconductor light-emitting element 30A to be driven by the drive circuit 40A, and the protection diode 70A.

[0141] 10 , the first intermediate electrode 101A is elongated in the Y-axis direction in plan view and is disposed at a position overlapping the second surface electrode 62A and the fifth surface electrode 65A (both see FIG. 3 ), the first back surface electrode 81A (see FIG. 8 ), and the first intermediate electrode 91A (see FIG. 9 ).

[0142] The second intermediate electrode 102A is disposed at a position overlapping the first surface electrode 61A (see FIG. 3), the second back surface electrode 82A (see FIG. 8), and the second intermediate electrode 92A (see FIG. 9) in a plan view. The second intermediate electrode 102A has, for example, an elliptical shape in a plan view. The second intermediate electrode 102A is disposed adjacent to or close to the first intermediate electrode 101A in the X-axis direction.

[0143] The third intermediate electrode 103A is disposed at a position overlapping the third front surface electrode 63A (see FIG. 3), the third back surface electrode 83A (see FIG. 8), and the third intermediate electrode 93A (see FIG. 9) in a plan view. The third intermediate electrode 103A has, for example, a circular shape in a plan view. The third intermediate electrode 103A is disposed, for example, in a circular opening provided in the fourth intermediate electrode 104A.

[0144] The fourth intermediate electrode 104A is disposed in a position overlapping a portion of the fourth surface electrode 64 (see FIG. 3 ) in the first partition region SP1, the fourth back surface electrode 84A and the fifth back surface electrode 85A (both see FIG. 8 ), and the fourth intermediate electrode 94A and the fifth intermediate electrode 95A (both see FIG. 9 ) in a plan view. The fourth intermediate electrode 104A can also be said to be disposed in a corner portion of the second substrate 27B in a plan view. The fourth intermediate electrode 104A includes a portion extending to a position adjacent to the first intermediate electrodes 101A and 101B in a plan view.

[0145] The fifth intermediate electrode 105A is arranged at a position overlapping the sixth front surface electrode 66A (see FIG. 3), the sixth back surface electrode 86A (see FIG. 8), and the second intermediate electrode 92A (see FIG. 9) in a plan view. The fifth intermediate electrode 105A has, for example, a rectangular shape in a plan view. The fifth intermediate electrode 105A is arranged, for example, between the first intermediate electrode 101A and the fourth intermediate electrode 104A in the X-axis direction in a plan view. The fifth intermediate electrode 105A is arranged at a position adjacent to the first side surface 23 in the Y-axis direction in a plan view.

[0146] The first to fifth intermediate electrodes 101B, 102B, 103B, 104A, and 105B are provided for electrical connection between the switching element 412 and capacitor 422 of the drive circuit 40B shown in Figure 4, the semiconductor light-emitting element 30B to be driven by the drive circuit 40B, and the protection diode 70B.

[0147] 10 , the first intermediate electrode 101B is elongated in the X-axis direction in plan view and is disposed at a position overlapping the second surface electrode 62B and the fifth surface electrode 65B (both see FIG. 3 ), the first back surface electrode 81B (see FIG. 8 ), and the first intermediate electrode 91B (see FIG. 9 ).

[0148] The second intermediate electrode 102B is disposed at a position overlapping the first surface electrode 61B (see FIG. 3), the second back surface electrode 82B (see FIG. 8), and the second intermediate electrode 92B (see FIG. 9) in a plan view. The second intermediate electrode 102B has, for example, an elliptical shape in a plan view. The second intermediate electrode 102B is disposed between the first intermediate electrode 101B and the fourth intermediate electrode 104A in the Y-axis direction. The second intermediate electrode 102B is disposed spaced apart from the second intermediate electrode 102A in the X-axis direction.

[0149] The third intermediate electrode 103B is arranged at a position overlapping the third front surface electrode 63B (see FIG. 3), the third back surface electrode 83B (see FIG. 8), and the third intermediate electrode 93B (see FIG. 9) in a plan view. The third intermediate electrode 103B has, for example, a circular shape in a plan view. The third intermediate electrode 103B is arranged adjacent to or close to the fourth intermediate electrode 104A in the X-axis direction and the Y-axis direction. The third intermediate electrode 103B is arranged on the opposite side of the second intermediate electrode 102B from the second intermediate electrode 102A in the X-axis direction.

[0150] The fifth intermediate electrode 105B is arranged in a position overlapping the sixth front surface electrode 66B (see FIG. 3), the sixth back surface electrode 86B (see FIG. 8), and the second intermediate electrode 92B (see FIG. 9) in a plan view. The fifth intermediate electrode 105B has, for example, a rectangular shape in a plan view. The fifth intermediate electrode 105B is arranged, for example, between the first intermediate electrode 101B and the fourth intermediate electrode 104A in the Y-axis direction in a plan view. The fifth intermediate electrode 105B is arranged in a position adjacent to the fourth side surface 26 in the X-axis direction in a plan view.

[0151] In the second partition region SP2 (the lower left region in FIG. 10), first intermediate electrodes 101C and 101D, second intermediate electrodes 102C and 102D, third intermediate electrodes 103C and 103D, a fourth intermediate electrode 104B, and fifth intermediate electrodes 105C and 105D are arranged.

[0152] 4, the semiconductor light emitting element 30C to be driven by the drive circuit 40C, and the protection diode 70C. The first to fifth intermediate electrodes 101D, 102D, 103D, 104B, and 105D are provided for electrically connecting the switching element 414 and capacitor 424 of the drive circuit 40D, the semiconductor light emitting element 30D to be driven by the drive circuit 40D, and the protection diode 70D.

[0153] 10 , the first to third intermediate electrodes 101C, 102C, 103C, and the fifth intermediate electrode 105C arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third intermediate electrodes 101B, 102B, 103B, and the fifth intermediate electrode 105B arranged in the first partition region SP1. The first to third intermediate electrodes 101D, 102D, 103D, and the fifth intermediate electrode 105D arranged in the second partition region SP2 are rotated 90° clockwise with respect to the first to third intermediate electrodes 101A, 102A, 103A, and the fifth intermediate electrode 105A arranged in the first partition region SP1. The fourth intermediate electrode 104B and the fourth intermediate electrode 104A are symmetrical with respect to the virtual center line VC. Therefore, detailed description of the arrangement of the first intermediate electrodes 101C and 101D, the second intermediate electrodes 102C and 102D, the third intermediate electrodes 103C and 103D, the fourth intermediate electrode 104B, and the fifth intermediate electrodes 105C and 105D will be omitted.

[0154] In the third partition region SP3 (the upper right region in FIG. 10), first intermediate electrodes 101E and 101F, second intermediate electrodes 102E and 102F, third intermediate electrodes 103E and 103F, a fourth intermediate electrode 104C, and fifth intermediate electrodes 105E and 105F are arranged.

[0155] 5, the semiconductor light emitting element 30E to be driven by the drive circuit 40E, and the protection diode 70E. The first to fifth intermediate electrodes 101F, 102F, 103F, 104C, and 105F are provided for electrically connecting the switching element 416 and capacitor 426 of the drive circuit 40F, the semiconductor light emitting element 30F to be driven by the drive circuit 40F, and the protection diode 70F.

[0156] 10 , the first to third intermediate electrodes 101E, 102E, 103E and the fifth intermediate electrode 105E arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third intermediate electrodes 101B, 102B, 103B and the fifth intermediate electrode 105B arranged in the first partition region SP1. The first to third intermediate electrodes 101F, 102F, 103F and the fifth intermediate electrode 105F arranged in the third partition region SP3 are rotated 90° counterclockwise with respect to the first to third intermediate electrodes 101A, 102A, 103A and the fifth intermediate electrode 105A arranged in the first partition region SP1. The fourth intermediate electrode 104C and the fourth intermediate electrode 104A are symmetrical with respect to the virtual center line HC. Therefore, detailed description of the arrangement of the first intermediate electrodes 101E and 101F, the second intermediate electrodes 102E and 102F, the third intermediate electrodes 103E and 103F, the fourth intermediate electrode 104C, and the fifth intermediate electrodes 105E and 105F will be omitted.

[0157] In the fourth partition region SP4 (upper left region in FIG. 10), first intermediate electrodes 101G and 101H, second intermediate electrodes 102G and 102H, third intermediate electrodes 103G and 103H, fourth intermediate electrode 104D, and fifth intermediate electrodes 105G and 105H are arranged.

[0158] 6, the first to fifth intermediate electrodes 101G, 102G, 103G, 104D, and 105G are provided for electrically connecting the switching element 417 and capacitor 427 of the drive circuit 40G, the semiconductor light emitting element 30G to be driven by the drive circuit 40G, and the protection diode 70G. The first to fifth intermediate electrodes 101H, 102H, 103H, 104D, and 105H are provided for electrically connecting the switching element 418 and capacitor 428 of the drive circuit 40H, the semiconductor light emitting element 30H to be driven by the drive circuit 40H, and the protection diode 70H.

[0159] 10 , the first to third intermediate electrodes 101G, 102G, 103G, and the fifth intermediate electrode 105G arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third intermediate electrodes 101D, 102D, 103D, and the fifth intermediate electrode 105D arranged in the second partition region SP2. The first to third intermediate electrodes 101H, 102H, 103H, and the fifth intermediate electrode 105H arranged in the fourth partition region SP4 are rotated 90° clockwise with respect to the first to third intermediate electrodes 101C, 102C, 103C, and the fifth intermediate electrode 105C arranged in the second partition region SP2. The fourth intermediate electrode 104D and the fourth intermediate electrode 104B are symmetrical with respect to the imaginary center line HC. Therefore, detailed description of the arrangement of the first intermediate electrodes 101G, 101H, second intermediate electrodes 102G, 102H, third intermediate electrodes 103G, 103H, fourth intermediate electrode 104D, and fifth intermediate electrodes 105G, 105H will be omitted.

[0160] [Connection Structure Between Electrode Layers] The substrate 20 includes a plurality of vias (connection conductors) that electrically connect the first electrode layer 28A (front electrode layer), the second electrode layer 28B (rear electrode layer), the third electrode layer 28C (front-side intermediate electrode layer), and the fourth electrode layer 28D (rear-side intermediate electrode layer). For example, as shown in Figures 3 to 10 , the substrate 20 includes first vias 111A to 111H, second vias 112A to 112H, third vias 113A to 113H, fourth vias 114A to 114D, fifth vias 115A to 115H, sixth vias 116A to 116H, and seventh vias 117A to 117H that penetrate the first to third base materials 27A to 27C, the third electrode layer 28C, and the fourth electrode layer 28D, respectively, in the thickness direction of the substrate 20. The vias may penetrate at least one of the first electrode layer 28 A and the second electrode layer 28 B. The vias may be made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0161] 3 and 7 to 10, the first vias 111A to 111H are arranged in a central region AC of the substrate 20. The second vias 112A to 112H, the third vias 113A to 113H, the fourth vias 114A to 114D, the fifth vias 115A to 115H, and the sixth vias 116A to 116H are arranged in a peripheral region AP of the substrate 20 and are arranged in a rotationally symmetric relationship. As described above, the layout of the multiple vias in the first to fourth partitioned regions SP1 to SP4, which are partitioned based on the imaginary center lines VC and HC, will be described.

[0162] The first partitioned region SP1 includes first vias 111A and 111B, second vias 112A and 112B, third vias 113A and 113B, fourth via 114A, fifth vias 115A and 115B, sixth vias 116A and 116B, and seventh vias 117A and 117B.

[0163] The first via 111A electrically connects the first surface electrode 61A of the first electrode layer 28A, the second back surface electrode 82A of the second electrode layer 28B, the second intermediate electrode 92A of the third electrode layer 28C, and the second intermediate electrode 102A of the fourth electrode layer 28D. The number of first vias 111A is not particularly limited, and may be one or more at positions where the first surface electrode 61A, the second back surface electrode 82A, and the second intermediate electrodes 92A and 102A overlap in a plan view, for example.

[0164] The second via 112A electrically connects the second front surface electrode 62A of the first electrode layer 28A, the first rear surface electrode 81A of the second electrode layer 28B, the first intermediate electrode 91A of the third electrode layer 28C, and the first intermediate electrode 101A of the fourth electrode layer 28D. In the first embodiment, there is one second via 112A, but there may be multiple second vias 112A.

[0165] The third via 113A electrically connects the third surface electrode 63A of the first electrode layer 28A, the third back surface electrode 83A of the second electrode layer 28B, the third intermediate electrode 93A of the third electrode layer 28C, and the third intermediate electrode 103A of the fourth electrode layer 28D. The number of third vias 113A is not particularly limited, and may be one or more at positions where the third surface electrode 63A, the third back surface electrode 83A, the third intermediate electrode 93A, and the third intermediate electrode 103A overlap in a plan view, for example.

[0166] The fourth via 114A electrically connects the fourth surface electrode 64 of the first electrode layer 28A, the fourth back surface electrode 84A of the second electrode layer 28B, the fourth intermediate electrode 94A of the third electrode layer 28C, and the fourth intermediate electrode 104A of the fourth electrode layer 28D. The number of fourth vias 114A is not particularly limited, and may be one or more at positions where the fourth surface electrode 64, the fourth back surface electrode 84A, the fourth intermediate electrode 94A, and the fourth intermediate electrode 104A overlap in a plan view. In the first embodiment, a large number of fourth vias 114A are arranged in a matrix (e.g., 4 × 8) at corner portions of the substrate 20.

[0167] The fifth via 115A electrically connects the fifth surface electrode 65A of the first electrode layer 28A, the first back surface electrode 81A of the second electrode layer 28B, the first intermediate electrode 91A of the third electrode layer 28C, and the first intermediate electrode 101A of the fourth electrode layer 28D. The number of fifth vias 115A is not particularly limited, and may be one or more at positions where the fifth surface electrode 65A, the first back surface electrode 81A, the first intermediate electrode 91A, and the first intermediate electrode 101A overlap in a plan view. In the first embodiment, for example, a large number of fifth vias 115A are arranged in a matrix (e.g., 2 × 5).

[0168] The sixth via 116A electrically connects the sixth surface electrode 66A of the first electrode layer 28A, the sixth back surface electrode 86A of the second electrode layer 28B, the second intermediate electrode 92A of the third electrode layer 28C, and the fifth intermediate electrode 105A of the fourth electrode layer 28D. The number of sixth vias 116A is not particularly limited, and may be one or more at positions where the sixth surface electrode 66A, the sixth back surface electrode 86A, the second intermediate electrode 92A, and the fifth intermediate electrode 105A overlap in a plan view, for example.

[0169] The seventh via 117A electrically connects the fourth surface electrode 64 of the first electrode layer 28A, the fifth back surface electrode 85A of the second electrode layer 28B, the fifth intermediate electrode 95A of the third electrode layer 28C, and the fourth intermediate electrode 104A of the fourth electrode layer 28D. The number of seventh vias 117A is not particularly limited, and may be one or more at positions where the fourth surface electrode 64, the fifth back surface electrode 85A, the fifth intermediate electrode 95A, and the fourth intermediate electrode 104A overlap in a plan view, for example.

[0170] In the first partition region SP1, the first, second, third, fifth, sixth, and seventh vias 111B, 112B, 113B, 115B, 116B, and 117B are arranged in the same manner as the above-described first, second, third, fifth, sixth, and seventh vias 111A, 112A, 113A, 115A, 116A, and 117A. Therefore, detailed description of the first, second, third, fifth, sixth, and seventh vias 111B, 112B, 113B, 115B, 116B, and 117B will be omitted.

[0171] The second divided region SP2 includes the first vias 111C and 111D, the second vias 112C and 112D, the third vias 113C and 113D, the fourth via 114B, the fifth vias 115C and 115D, the sixth vias 116C and 116D, and the seventh vias 117C and 117D. The third divided region SP3 includes the first vias 111E and 111F, the second vias 112E and 112F, the third vias 113E and 113F, the fourth via 114C, the fifth vias 115E and 115F, the sixth vias 116E and 116F, and the seventh vias 117E and 117F. The fourth divided region SP4 includes first vias 111G, 111H, second vias 112G, 112H, third vias 113G, 113H, fourth via 114D, fifth vias 115G, 115H, sixth vias 116G, 116H, and seventh vias 117G, 117H. The arrangement of these vias in the second to fourth divided regions SP2 to SP4 is similar to the arrangement of the vias in the first divided region SP1 described above, and therefore detailed description thereof will be omitted.

[0172] [Circuit Configuration of Semiconductor Light-Emitting Device] The circuit configuration of the semiconductor light-emitting device 10 will be described with reference to Fig. 11 and Fig. 12. Fig. 11 and Fig. 12 schematically show the circuit configuration of the semiconductor light-emitting device 10 of the first embodiment.

[0173] 11 and 12, a light-emitting system 300 including the semiconductor light-emitting device 10 includes a DC power supply 301, a capacitor 302 connected in parallel with the DC power supply 301, a current-limiting resistor 303, backflow prevention diodes 304A to 304H, gate drivers 305A to 305H, pulse generators 306A to 306H, and control power supplies 307A to 307H. The backflow prevention diodes 304A to 304H, the gate drivers 305A to 305H, the pulse generators 306A to 306H, and the control power supplies 307A to 307H are provided corresponding to the drive circuits 40A to 40H, respectively.

[0174] The light emitting system 300 having such a configuration may be applied to LiDAR (Light Detection and Ranging), which is an example of a remote sensing method that measures distance by irradiating a target with light using, for example, near-infrared light, visible light, or ultraviolet light and receiving the reflected light with an optical sensor (not shown). The light emitting system 300 is applied as a light source for LiDAR.

[0175] The DC power supply 301, the capacitor 302, and the current limiting resistor 303 are configured to supply current to the semiconductor light emitting elements 30A to 30H and the drive circuits 40A to 40H. The DC power supply 301, the capacitor 302, and the current limiting resistor 303 are an example of a "power supply input unit." A first terminal of the current limiting resistor 303 is electrically connected to the positive electrode of the DC power supply 301.

[0176] The anodes of the reverse current prevention diodes 304A to 304H are electrically connected to the second terminal of the current limiting resistor 303. The cathodes of the reverse current prevention diodes 304A to 304H are electrically connected to the anode electrodes 34 of the semiconductor light emitting elements 30A to 30H and the second electrodes 42B of the capacitors 421 to 428 via the first rear surface electrodes 81A to 81H (see FIG. 8).

[0177] The gate drivers 305A to 305H are electrically connected to the gate electrodes 41G of the switching elements 411 to 418 of the drive circuits 40A to 40H, respectively. In the first embodiment, the gate drivers 305A to 305H are electrically connected to the third rear surface electrodes 83A to 83H (see FIG. 8 ), which are electrically connected to the gate electrodes 41G of the switching elements 411 to 418. The gate drivers 305A to 305H are configured to individually drive the switching elements 411 to 418 by applying gate voltage signals to the gate electrodes 41G of the switching elements 411 to 418, respectively.

[0178] The pulse generators 306A to 306H and the control power supplies 307A to 307H are electrically connected to the gate drivers 305A to 305H, respectively. The pulse generators 306A to 306H are configured to output pulse signals to the gate drivers 305A to 305H, respectively, for controlling the switching elements 411 to 418. The control power supplies 307A to 307H are configured to apply operating voltages to the gate drivers 305A to 305H, respectively.

[0179] The negative electrode of the DC power supply 301, the capacitor 302, the pulse generators 306A to 306H, the first electrodes 42A of the capacitors 421 to 428, the negative electrodes of the control power supplies 307A to 307H, and the source electrodes 41S of the switching elements 411 to 418 are electrically connected to a ground terminal (fourth back surface electrodes 84A to 84D of the second electrode layer 28B (see FIG. 8)) via ground wiring (fourth surface electrode 64 of the first electrode layer 28A, fourth intermediate electrodes 94A to 94D of the third electrode layer 28C, and fourth intermediate electrodes 104A to 104D of the fourth electrode layer 28D (see FIGS. 3, 9, and 10)).

[0180] The drain electrodes 41D of the switching elements 411 to 418 are electrically connected to the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H and the anode electrodes 71 of the protection diodes 70A to 70H, respectively. The cathode electrodes 72 of the protection diodes 70A to 70H are electrically connected to the anode electrodes 34 of the semiconductor light emitting elements 30A to 30H, respectively.

[0181] In the semiconductor light-emitting device 10 configured as described above, when the switching elements 411 to 418 of the drive circuits 40A to 40H are in the OFF state, the capacitors 421 to 428 are charged by the DC power supply 301. When the switching elements 411 to 418 are switched from the OFF state to the ON state, current flows from the capacitors 421 to 428 to the semiconductor light-emitting elements 30A to 30H. This causes pulsed laser light to be emitted from the semiconductor light-emitting elements 30A to 30H. In this way, the drive circuits 40A to 40H are configured to individually drive the semiconductor light-emitting elements 30A to 30H.

[0182] As an example, the drive circuits 40A-40H sequentially drive the semiconductor light-emitting elements 30A-30H. In this case, the pulsed light emission of the semiconductor light-emitting elements 30A-30H can be adjusted so that the pulse intervals of the laser light emitted from the semiconductor light-emitting device 10 are shorter than in a semiconductor light-emitting device having, for example, a single semiconductor light-emitting element. This allows for an increase in the number of pulses per unit time. Furthermore, by having the semiconductor light-emitting elements 30A-30H emit light in sequence, heat generation from each of the semiconductor light-emitting elements 30A-30H can be suppressed compared to a semiconductor light-emitting device having a single semiconductor light-emitting element.

[0183] 13 to 18, the detailed configuration of the semiconductor light emitting elements 30A to 30H will be described. Note that the semiconductor light emitting elements 30B to 30H have the same configuration as the semiconductor light emitting element 30A, and therefore detailed description thereof will be omitted.

[0184] Fig. 13 schematically shows a perspective structure of the semiconductor light emitting element 30A mounted on the submount substrate 50. Fig. 14 schematically shows a cross-sectional structure of the semiconductor light emitting element 30A and the submount substrate 50 mounted on the substrate 20. Fig. 15 schematically shows the planar structure of the submount substrate 50. Fig. 16 schematically shows the back surface structure of the submount substrate 50. Fig. 17 schematically shows the cross-sectional structure of the semiconductor light emitting element 30A. Fig. 18 schematically shows the back surface structure of the semiconductor light emitting element 30A.

[0185] As shown in Figure 13, the semiconductor light emitting device 10 includes a submount substrate 50 on which the semiconductor light emitting element 30A is mounted. The submount substrate 50 has a rectangular flat plate shape with its thickness direction in the Z-axis direction. In one example, the submount substrate 50 has a square shape in a plan view. The submount substrate 50 is slightly larger than the semiconductor light emitting element 30A in a plan view. In one example, the submount substrate 50 is 1.2 mm square.

[0186] 14, the submount substrate 50 includes an insulating base material 51. The base material 51 is made of, for example, AlN or Al ２ O ３may be used. In the first embodiment, AlN is used for the base material 51. The base material 51 includes a first base material surface 51A and a second base material surface 51B opposite to the first base material surface 51A. The first base material surface 51A is the surface on which the semiconductor light emitting element 30A is mounted. The second base material surface 51B is the surface on which the semiconductor light emitting element 30A is mounted to the substrate 20. More specifically, the second base material surface 51B is the mounting surface on which the first surface electrode 61A and the second surface electrode 62A of the first electrode layer 28A are mounted.

[0187] 14 to 16, the submount substrate 50 includes a substrate-side anode electrode 52 and a substrate-side cathode electrode 53. Both the substrate-side anode electrode 52 and the substrate-side cathode electrode 53 penetrate the base material 51 in the Z direction. Each of the substrate-side anode electrode 52 and the substrate-side cathode electrode 53 is made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0188] The substrate-side anode electrode 52 includes a first anode electrode 52A provided on the first substrate surface 51A, a second anode electrode 52B provided on the second substrate surface 51B, and a first via 52C provided within the substrate 51.

[0189] The first anode electrode 52A is provided at the center of the first substrate surface 51A in the X-axis direction and the Y-axis direction. The first anode electrode 52A has a circular shape in a plan view. The shape of the first anode electrode 52A in a plan view can be changed as desired.

[0190] The second anode electrode 52B is provided at a position overlapping the first anode electrode 52A in a plan view. The second anode electrode 52B is provided at the center of the second substrate surface 51B in the X-axis direction and the Y-axis direction. The second anode electrode 52B has a circular shape in a plan view. In one example, the second anode electrode 52B may have the same shape and size as the first anode electrode 52A in a plan view.

[0191] The first via 52C connects the first anode electrode 52A and the second anode electrode 52B. At least one first via 52C may be provided at a position where the first anode electrode 52A and the second anode electrode 52B overlap in a plan view. In one example, one first via 52C is provided in the center of the first anode electrode 52A (second anode electrode 52B) in a plan view.

[0192] The substrate-side cathode electrode 53 includes a first cathode electrode 53A provided on the first substrate surface 51A, a second cathode electrode 53B provided on the second substrate surface 51B, and a second via 53C provided within the substrate 51.

[0193] The first cathode electrode 53A is disposed at a distance from the first anode electrode 52A in a plan view. The first cathode electrode 53A is disposed in a ring shape surrounding the first anode electrode 52A in a plan view. The first cathode electrode 53A includes a rectangular outer edge in a plan view. The first cathode electrode 53A is disposed on the outer periphery of the first substrate surface 51A. In one example, the first cathode electrode 53A includes a circular opening in a plan view. Therefore, the first cathode electrode 53A is disposed so that its width increases toward the four corner portions. It can also be said that the first anode electrode 52A is disposed within the opening of the first cathode electrode 53A in a plan view.

[0194] The second cathode electrode 53B is disposed at a distance from the second anode electrode 52B in a plan view. The second cathode electrode 53B is disposed at a position overlapping the first cathode electrode 53A in a plan view. The second cathode electrode 53B is disposed in a ring shape surrounding the second anode electrode 52B in a plan view. The second cathode electrode 53B is disposed on the outer periphery of the second substrate surface 51B. In one example, the second cathode electrode 53B includes a circular opening in a plan view. It can also be said that the second anode electrode 52B is disposed within the opening of the second cathode electrode 53B in a plan view. In one example, the second cathode electrode 53B may have the same shape and size as the first cathode electrode 53A in a plan view.

[0195] The second via 53C connects the first cathode electrode 53A and the second cathode electrode 53B. At least one second via 53C is provided at a position where the first cathode electrode 53A and the second cathode electrode 53B overlap in a plan view. In one example, as shown in Fig. 15 , the second via 53C is provided at each of the four corners of the first cathode electrode 53A in a plan view.

[0196] 13 and 14 , semiconductor light emitting element 30A is mounted on submount substrate 50 so that second element surface 32 faces first base surface 51A of submount substrate 50. As shown in Fig. 14 , anode electrode 34 provided on second element surface 32 is bonded to first anode electrode 52A of submount substrate 50 with conductive bonding material SD. Cathode electrode 35 provided on second element surface 32 is bonded to first cathode electrode 53A of submount substrate 50 with conductive bonding material SD.

[0197] The thickness of the submount substrate 50 may be equal to, for example, the thickness of the semiconductor light emitting element 30A. Alternatively, the thickness of the submount substrate 50 may be thicker than, for example, the thickness of the semiconductor light emitting element 30A. The thickness of the submount substrate 50 can be defined by the distance between the first substrate surface 51A and the second substrate surface 51B in the Z-axis direction. The thickness of the semiconductor light emitting element 30A can be defined by the distance between the first element surface 31 and the second element surface 32 in the Z-axis direction. In one example, the thickness of the submount substrate 50 is approximately 100 μm. In another example, the thickness of the semiconductor light emitting element 30A is approximately 100 μm. Note that in FIGS. 13 and 14 , the thickness of the semiconductor light emitting element 30A is shown thicker than it actually is in order to illustrate the internal structure of the semiconductor light emitting element 30A.

[0198] 17 , the semiconductor light emitting element 30A includes a semiconductor substrate 36 and a semiconductor layer 37 provided on the semiconductor substrate 36. The semiconductor light emitting element 30A is mounted on the substrate 20 such that the semiconductor layer 37 is disposed between the substrate 20 and the semiconductor substrate 36 in the Z-axis direction (thickness direction of the substrate 20).

[0199] The semiconductor substrate 36 has a rectangular flat plate shape with its thickness direction in the Z-axis direction. The semiconductor substrate 36 includes a first element surface 31. The semiconductor substrate 36 includes a first surface 36A and a second surface 36B opposite to the first surface 36A. The semiconductor light emitting element 30A is configured so that light is emitted from the second surface 36B of the semiconductor substrate 36. In other words, the second surface 36B of the semiconductor substrate 36 constitutes the first element surface 31 of the semiconductor light emitting element 30A.

[0200] The semiconductor substrate 36 is made of a material containing, for example, any one of n-type gallium arsenide (GaAs), indium phosphide (InP), and gallium nitride (GaN). The semiconductor substrate 36 is used to epitaxially grow the semiconductor layer 37. In the first embodiment, an n-type GaAs substrate is used as the semiconductor substrate 36.

[0201] The semiconductor layer 37 is provided on the first surface 36A of the semiconductor substrate 36. The semiconductor layer 37 is configured to generate light. As an example of this configuration, the semiconductor layer 37 includes an active layer 37A, a photonic crystal layer 37B, a first cladding layer 37C, a second cladding layer 37D, and a contact layer 37E. These layers are stacked in the Z-axis direction (the thickness direction of the semiconductor light emitting device 30A).

[0202] The active layer 37A and the photonic crystal layer 37B are interposed between the first cladding layer 37C and the second cladding layer 37D. The contact layer 37E constitutes the uppermost layer of the semiconductor layer 37.

[0203] The second cladding layer 37D is formed by epitaxial growth on the first surface 36A of the semiconductor substrate 36. The second cladding layer 37D is in contact with the first surface 36A of the semiconductor substrate 36. The second cladding layer 37D may be epitaxially grown on the first surface 36A of the semiconductor substrate 36 via a buffer layer (not shown). In this case, the buffer layer is interposed between the first surface 36A of the semiconductor substrate 36 and the second cladding layer 37D.

[0204] The active layer 37A is formed by epitaxial growth on the second cladding layer 37D. In one example, the active layer 37A is in contact with the second cladding layer 37D. The active layer 37A is a layer that generates light when a current is supplied to it. The refractive index of the active layer 37A is greater than the refractive indexes of the second cladding layer 37D and the first cladding layer 37C. The band gap of the active layer 37A is smaller than the band gaps of the second cladding layer 37D and the first cladding layer 37C. In one example, the active layer 37A includes a multiple quantum well structure in which well layers and barrier layers are alternately stacked.

[0205] The photonic crystal layer 37B is provided between the second cladding layer 37D and the active layer 37A, or between the active layer 37A and the first cladding layer 37C. In the example shown in Fig. 17, the photonic crystal layer 37B is provided between the active layer 37A and the first cladding layer 37C. The photonic crystal layer 37B is in contact with both the active layer 37A and the first cladding layer 37C.

[0206] First cladding layer 37C is formed by epitaxial growth on photonic crystal layer 37B and is in contact with photonic crystal layer 37B.

[0207] The contact layer 37E is formed by epitaxial growth on the first cladding layer 37C. In one example, the contact layer 37E is in contact with the first cladding layer 37C. The contact layer 37E has a bandgap different from that of the first cladding layer 37C. In one example, the bandgap of the contact layer 37E is smaller than the bandgap of the first cladding layer 37C.

[0208] 17 and 18 , the semiconductor layer 37 includes a groove 38 that is annular in plan view. In one example, the groove 38 has a circular ring shape in plan view. In one example, the groove 38 penetrates the semiconductor layer 37 in the Z-axis direction. Therefore, the groove 38 exposes the first surface 36A of the semiconductor substrate 36. The groove 38 is provided in a tapered shape such that the opening width increases from the first surface 36A of the semiconductor substrate 36 toward the contact layer 37E. The groove 38 is provided so as to surround the anode electrode 34 in plan view.

[0209] The semiconductor layer 37 is separated into a mesa portion 37P and a peripheral portion 37Q by the groove 38. The mesa portion 37P and the peripheral portion 37Q are spaced apart from each other in a plan view. The mesa portion 37P constitutes a portion of the semiconductor layer 37 that is surrounded by the groove 38. The peripheral portion 37Q constitutes a portion of the semiconductor layer 37 that is located outward from the groove 38. In the first embodiment, the mesa portion 37P has a truncated cone shape.

[0210] The mesa portion 37P includes a main surface 37PA formed by the contact layer 37E, and a side surface 37PB. The side surface 37PB is formed by, for example, the active layer 37A, the photonic crystal layer 37B, the first cladding layer 37C, the second cladding layer 37D, and the contact layer 37E.

[0211] The outer peripheral portion 37Q includes a main surface 37QA formed by the contact layer 37E, and an inner surface 37QB. The inner surface 37QB is formed by, for example, the active layer 37A, the photonic crystal layer 37B, the first cladding layer 37C, the second cladding layer 37D, and the contact layer 37E.

[0212] The semiconductor light emitting element 30A includes an insulating layer 39 provided on the contact layer 37E. The insulating layer 39 covers the contact layer 37E. In other words, the insulating layer 39 can be said to be a protective layer that protects the semiconductor layer 37. The insulating layer 39 is made of silicon oxide (SiO ２ The insulating layer 39 may be made of a material containing at least one of silicon nitride (SiN) and silicon dioxide (SiO 2 ). The insulating layer 39 may be made of a material containing a polyimide resin. The surface of the insulating layer 39 forms the second element surface 32 of the semiconductor light emitting element 30A.

[0213] The insulating layer 39 includes a first insulating layer 39A that covers the mesa portion 37P and a second insulating layer 39B that covers the outer peripheral portion 37Q. The first insulating layer 39A covers the main surface 37PA of the mesa portion 37P but does not cover the side surface 37PB of the mesa portion 37P. Therefore, the side surface 37PB is exposed from the first insulating layer 39A. The first insulating layer 39A includes an opening that exposes a portion of the main surface 37PA of the mesa portion 37P.

[0214] The anode electrode 34 is provided on the first insulating layer 39A. The anode electrode 34 includes a contact portion 34A that contacts the contact layer 37E through an opening in the first insulating layer 39A. The contact portion 34A can be said to penetrate the first insulating layer 39A and contact the mesa portion 37P. Thus, the first insulating layer 39A includes a portion that is interposed between the mesa portion 37P and the anode electrode 34 in the Z-axis direction. In other words, the first insulating layer 39A can be said to be provided between the mesa portion 37P and the anode electrode 34. The anode electrode 34 is bonded to the first anode electrode 52A of the substrate-side anode electrode 52 on the submount substrate 50, for example, by a conductive adhesive material. This electrically connects the anode electrode 34 to the first anode electrode 52A. The first anode electrode 52A is electrically connected to the second surface electrode 62A of the first electrode layer 28A through the first via 52C and the second anode electrode 52B. Therefore, the anode electrode 34 is electrically connected to the second surface electrode 62A.

[0215] The second insulating layer 39B covers the major surface 37QA and the inner surface 37QB of the outer peripheral portion 37Q. The cathode electrode 35 is provided on the second insulating layer 39B. Therefore, it can be said that the second insulating layer 39B is provided between the outer peripheral portion 37Q and the cathode electrode 35. The cathode electrode 35 includes a first portion 35A covering the major surface 37QA of the outer peripheral portion 37Q and a second portion 35B provided in the groove 38. The second portion 35B includes a contact portion 35C in contact with at least one of the side surface 37PB of the mesa portion 37P and the first surface 36A of the semiconductor substrate 36. In the first embodiment, the contact portion 35C is in contact with both the side surface 37PB of the mesa portion 37P and the first surface 36A of the semiconductor substrate 36.

[0216] 18 , the cathode electrode 35 is provided so as to surround the anode electrode 34 in a plan view. The outer edge of the cathode electrode 35 is rectangular in a plan view. On the other hand, the inner edge of the contact portion 35C is circular. Therefore, the first portion 35A of the cathode electrode 35 is provided so as to become wider toward the four corner portions.

[0217] The first portion 35A of the cathode electrode 35 is joined to the first cathode electrode 53A (see FIG. 15 ) of the substrate-side cathode electrode 53 on the submount substrate 50, for example, by a conductive bonding material SD. This electrically connects the cathode electrode 35 to the first cathode electrode 53A. The first cathode electrode 53A is electrically connected to the first surface electrode 61A of the first electrode layer 28A through the second via 53C and the second cathode electrode 53B (both see FIG. 16 ). Therefore, the cathode electrode 35 is electrically connected to the first surface electrode 61A.

[0218] In the semiconductor light emitting device 30A configured as described above, a current supplied to the anode electrode 34 flows through the mesa portion 37P to the cathode electrode 35. In this case, the current flows through the active layer 37A of the mesa portion 37P, causing light to be emitted in the Z-axis direction.

[0219] [Current Path of Semiconductor Light-Emitting Device] The semiconductor light-emitting device 10 is embodied as a multi-channel drive type light-emitting module in which each of the drive circuits 40A-40H drives one or more (one in the first embodiment) semiconductor light-emitting elements 30A-30H. As described above, in the semiconductor light-emitting device 10, the drive circuits 40A-40H are mounted on the substrate 20 together with the semiconductor light-emitting elements 30A-30H. Therefore, the current path between the drive circuits 40A-40H and the semiconductor light-emitting elements 30A-30H that they drive is formed within the substrate 20.

[0220] 19 shows a current path CP of a current flowing through the switching element 411 and capacitor 421 of the drive circuit 40A and the semiconductor light emitting element 30A. The current path CP is indicated by a bold arrow.

[0221] The current path CP is configured in the shape of a loop in which current flows in the following order: the second electrode 42B of the capacitor 421, the fifth surface electrode 65A of the first electrode layer 28A, the fifth via 115A, the first intermediate electrode 91A of the third electrode layer 28C, the second via 112A, the second surface electrode 62A of the first electrode layer 28A, the anode electrode 34 of the semiconductor light emitting element 30A, the cathode electrode 35 of the semiconductor light emitting element 30A, the first surface electrode 61A of the first electrode layer 28A, the drain electrode 41D of the switching element 411, the source electrode 41S of the switching element 411 (see FIG. 3 ), the fourth surface electrode 64 of the first electrode layer 28A, and the first electrode 42A of the capacitor 421. As described above, a protection diode 70A (see FIG. 3 ) is connected in anti-parallel to the semiconductor light emitting element 30A. 19 does not show the drain electrode 41D, the source electrode 41S, and the fourth surface electrode 64 in the current path CP because the source electrode 41S is not shown. However, in reality, the current path CP is formed so that a current flows from the drain electrode 41D to the fourth surface electrode 64 via the source electrode 41S.

[0222] Although detailed description is omitted, each of the other drive circuits 40B to 40H has the same electrical connection as drive circuit 40A, and each of the other drive circuits 40B to 40H has a loop-shaped current path similar to the above-described current path CP. Each of the other protection diodes 70B to 70H has the same electrical connection as protection diode 70A.

[0223] [Operation of First Embodiment] The operation of the semiconductor light emitting device 10 of the first embodiment will be described. The semiconductor light emitting element 30A has an anode electrode 34 and a cathode electrode 35 provided on the second element surface 32. The semiconductor light emitting element 30A is mounted on a submount substrate 50. As a result, the anode electrode 34 is electrically connected to the substrate-side anode electrode 52 of the submount substrate 50, and the cathode electrode 35 is electrically connected to the substrate-side cathode electrode 53 of the submount substrate 50. The submount substrate 50 is then mounted on the first electrode layer 28A of the substrate 20. More specifically, the submount substrate 50 is mounted on the first electrode layer 28A so that the substrate-side anode electrode 52 is electrically connected to the second surface electrode 62A of the first electrode layer 28A, and the substrate-side cathode electrode 53 is electrically connected to the first surface electrode 61A of the first electrode layer 28A. As a result, the anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the second surface electrode 62A, and the cathode electrode 35 of the semiconductor light emitting element 30A is electrically connected to the first surface electrode 61A. Note that, like the semiconductor light emitting element 30A, the semiconductor light emitting elements 30B to 30H are also mounted on the first electrode layer 28A.

[0224] In this way, in the semiconductor light emitting elements 30A to 30H, the anode electrode 34 and the second surface electrode 62A are electrically connected, and the cathode electrode 35 and the first surface electrode 61A are electrically connected, without using wires, so that an increase in inductance due to wires can be suppressed.

[0225] [Effects of First Embodiment] The semiconductor light emitting device 10 of the first embodiment has the following effects. (1-1) The semiconductor light emitting device 10 includes a substrate 20 including a first substrate surface 21 and a second substrate surface 22 opposite to the first substrate surface 21, semiconductor light emitting elements 30A-30H mounted on the first substrate surface 21, and drive circuits 40A-40H provided on the substrate 20 and configured to drive the semiconductor light emitting elements 30A-30H. The substrate 20 includes second surface electrodes 62A-62H serving as front-side anode electrodes and first surface electrodes 61A-61H serving as front-side cathode electrodes, which are provided on the first substrate surface 21, and a second electrode layer 28B provided on the second substrate surface 22. Each of the semiconductor light emitting elements 30A to 30H includes a first element surface 31 including a light emitting region 33 that emits light, an anode electrode 34 provided on the side opposite the first element surface 31 and electrically connected to the second surface electrodes 62A to 62H, a cathode electrode 35 provided on the side opposite the first element surface 31 and electrically connected to the first surface electrodes 61A to 61H, a semiconductor substrate 36 including a first surface 36A and a second surface 36B opposite the first surface 36A and constituting the first element surface 31, and a semiconductor layer 37 provided on the first surface 36A and configured to generate light. The semiconductor light emitting elements 30A to 30H are mounted on the substrate 20 such that the semiconductor layer 37 is disposed between the semiconductor substrate 36 and the substrate 20 in the Z-axis direction, which is the thickness direction of the substrate 20.

[0226] According to this configuration, both the anode electrodes 34 and the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H can be disposed facing the first substrate surface 21 of the substrate 20. Therefore, both the anode electrodes 34 and the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H can be electrically connected to the second surface electrodes 62A to 62H and the first surface electrodes 61A to 61H of the substrate 20, respectively, without using wires. Therefore, the inductance of the semiconductor light emitting device 10 can be reduced compared to a configuration in which the anode electrodes 34 and the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H are connected to the second surface electrodes 62A to 62H and the first surface electrodes 61A to 61H, respectively, using wires.

[0227] (1-2) The cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H are provided so as to surround the anode electrodes 34 of the corresponding semiconductor light emitting elements 30A to 30H in a planar view. With this configuration, the current path flowing from the anode electrodes 34 to the cathode electrodes 35 is less likely to be biased in a planar view. Therefore, the intensity of the light emitted from the semiconductor light emitting elements 30A to 30H is less likely to be biased in a planar view.

[0228] (1-3) The semiconductor layer 37 includes a groove 38 that surrounds the anode electrode 34 in a plan view and exposes the semiconductor substrate 36. A portion of the cathode electrode 35 extends into the groove 38.

[0229] This configuration shortens the current path between the anode electrode 34 and the cathode electrode 35 that passes through the semiconductor layer 37. This reduces the electrical resistance in the current path between the anode electrode 34 and the cathode electrode 35.

[0230] (1-4) The semiconductor layer 37 includes a mesa portion 37P surrounded by a groove 38 and a peripheral portion 37Q provided outward from the groove 38. The semiconductor light emitting elements 30A to 30H include a first insulating layer 39A provided between the mesa portion 37P and the anode electrode 34, and a second insulating layer 39B provided between the peripheral portion 37Q and the cathode electrode 35. The second insulating layer 39B covers an inner surface 37QB of the peripheral portion 37Q that constitutes the groove 38. The anode electrode 34 includes a portion that penetrates the first insulating layer 39A and contacts the mesa portion 37P. The cathode electrode 35 includes a portion that extends into the groove 38 and contacts at least one of a side surface 37PB of the mesa portion 37P and the semiconductor substrate 36.

[0231] According to this configuration, the current path between the anode electrode 34 and the cathode electrode 35 that passes through the semiconductor substrate 36 can be shortened, or the current path that passes through the semiconductor substrate 36 can be omitted. This reduces the electrical resistance in the current path between the anode electrode 34 and the cathode electrode 35.

[0232] (1-5) The semiconductor light emitting device 10 includes a plurality of submount substrates 50 provided on the first substrate surface 21, and on which semiconductor light emitting elements 30A to 30H are respectively mounted. The submount substrate 50 includes an insulating base material 51, a substrate-side anode electrode 52 electrically connected to the anode electrode 34, and a substrate-side cathode electrode 53 electrically connected to the cathode electrode 35. Both the substrate-side anode electrode 52 and the substrate-side cathode electrode 53 penetrate the base material 51.

[0233] According to this configuration, by mounting a plurality of submount substrates 50, each having semiconductor light emitting elements 30A-30H mounted thereon, on first surface electrodes 61A-61H and second surface electrodes 62A-62H, respectively, it is possible to realize electrical connection between the anode electrodes 34 of semiconductor light emitting elements 30A-30H and second surface electrodes 62A-62H, and electrical connection between the cathode electrodes 35 of semiconductor light emitting elements 30A-30H and first surface electrodes 61A-61H. Therefore, the inductance of semiconductor light emitting device 10 can be reduced compared to a configuration in which the anode electrodes 34 and cathode electrodes 35 of semiconductor light emitting elements 30A-30H are connected to the second surface electrodes 62A-62H and first surface electrodes 61A-61H, respectively, using wires.

[0234] (1-6) The semiconductor light-emitting elements 30A to 30H are configured to emit light in a direction intersecting the first substrate surface 21. With this configuration, the semiconductor light-emitting elements 30A to 30H can be arranged in a central region AC that includes the center of the substrate 20. This reduces design constraints such as wiring layout compared to, for example, when semiconductor light-emitting elements configured as edge-emitting elements are arranged at the edge (peripheral region AP) of the substrate 20, and allows more semiconductor light-emitting elements to be arranged on the substrate 20 with a high degree of layout freedom. Therefore, the number of semiconductor light-emitting elements that can be mounted on the semiconductor light-emitting device 10 can be increased while preventing the semiconductor light-emitting device 10 from becoming larger.

[0235] (1-7) PCSEL elements are used for the semiconductor light-emitting elements 30A-30H. PCSEL elements are capable of high-output operation (high-brightness operation) by emitting beams with high beam quality and a narrow divergence angle. In particular, the beam divergence angle can be made extremely small (e.g., 1° or less) compared to edge-emitting elements, making it possible to omit collimating lenses, which are required when using edge-emitting elements. This reduces the number of components, thereby enabling the size of the semiconductor light-emitting elements 30A-30H and the miniaturization and cost reduction of the semiconductor light-emitting device 10.

[0236] (1-8) PCSEL elements have the characteristics of a narrow wavelength spectrum width and little temperature dependency of the operating wavelength, which can reduce, for example, optical noise and improve the optical characteristics of the semiconductor light-emitting device 10. This is advantageous when applying the semiconductor light-emitting device 10 to a laser system such as LiDAR.

[0237] (1-9) The semiconductor light emitting elements 30A to 30H are concentrated in a central region AC of the substrate 20. This allows for greater flexibility in the wiring design of the drive circuits 40A to 40H that drive the semiconductor light emitting elements 30A to 30H and the associated circuit elements. As a result, the number of channels (the number of semiconductor light emitting elements) can be further increased.

[0238] (1-10) The semiconductor light emitting elements 30A to 30H are arranged adjacent to one another in a matrix in the central region AC of the substrate 20. This makes it possible to mount more semiconductor light emitting elements on the semiconductor light emitting device 10 while preventing the semiconductor light emitting device 10 from becoming larger.

[0239] (1-11) The drive circuits 40A to 40H are arranged in a peripheral area AP surrounding the central area AC of the substrate 20. This allows, for example, the semiconductor light emitting elements 30A to 30H to be collectively arranged in the central area AC of the substrate 20, while the drive circuits 40A to 40H can be mounted in the peripheral area AP of the substrate 20 with a high degree of design freedom. This therefore facilitates multi-channelization.

[0240] (1-12) The substrate 20 includes first to fourth partitioned regions SP1 to SP4, which are divided by two imaginary center lines VC and HC. The semiconductor light emitting elements 30A to 30H and the drive circuits 40A to 40H are each disposed in one of the first to fourth partitioned regions SP1 to SP4. In this configuration, the semiconductor light emitting elements 30A to 30H and the drive circuits 40A to 40H can be disposed symmetrically (for example, rotationally symmetrically in the first embodiment) within the first to fourth partitioned regions SP1 to SP4. This facilitates the layout of the wiring design while achieving multi-channelization.

[0241] (1-13) Two or more of the semiconductor light emitting elements 30A to 30H are arranged in each of the first to fourth partitioned regions SP1 to PS4, and two or more of the drive circuits 40A to 40H are arranged in each of the first to fourth partitioned regions SP1 to PS4. With this configuration, when eight or more semiconductor light emitting elements are mounted in the semiconductor light emitting device 10, the drive circuits 40A to 40H can be arranged efficiently.

[0242] (1-14) The semiconductor light-emitting device 10 includes semiconductor light-emitting elements 30A-30H and drive circuits 40A-40H that drive the semiconductor light-emitting elements 30A-30H. With this configuration, a current path CP for current flowing through the drive circuits 40A-40H and the semiconductor light-emitting elements 30A-30H that they drive is formed on the substrate 20. This allows the current path CP to be shorter than when the drive circuits 40A-40H are provided external to the semiconductor light-emitting device 10. This reduces the inductance due to the length of the current path CP and the inductance variation of each current path CP. As a result, the pulse width of the laser light emitted by the semiconductor light-emitting elements 30A-30H can be shortened and the variation in pulse width can be reduced. In one example, the pulse width of the laser light emitted by the semiconductor light-emitting elements 30A-30H is 4 ns or less. Furthermore, in one example, the absolute value of the variation in the pulse width of the laser light emitted by the semiconductor light-emitting elements 30A-30H is 10% or less.

[0243] (1-15) The current path CP includes the third electrode layer 28C, which serves as a front-side intermediate electrode layer. This configuration makes it possible to reduce the length and area of ​​the loop-shaped current path between the semiconductor light-emitting elements 30A-30H and the drive circuits 40A-40H. This reduces the inductance caused by the current path.

[0244] (1-16) Each of the drive circuits 40A to 40H includes a plurality of capacitors 421 to 428 connected in parallel to one another. For example, the drive circuit 40A includes four capacitors 421 connected in parallel to one another, and the other drive circuits 40B to 40H also include the same number of capacitors 422 to 428. This configuration can reduce inductance compared to when each of the drive circuits 40A to 40H includes a single capacitor.

[0245] (1-17) The semiconductor light emitting device 10 includes protection diodes 70A to 70H connected in anti-parallel to the semiconductor light emitting elements 30A to 30H, respectively. This configuration prevents excessive reverse bias from being applied to the semiconductor light emitting elements 30A to 30H, thereby increasing the peak optical output of the semiconductor light emitting elements 30A to 30H.

[0246] (1-18) Horizontal transistors are used for the switching elements 411 to 418 of the drive circuits 40A to 40H. With this configuration, the drain electrodes 41D, source electrodes 41S, and gate electrodes 41G of the switching elements 411 to 418 can be arranged to face the first surface electrodes 61A to 61H, the fourth surface electrode 64, and the third surface electrodes 63A to 63H, respectively. This allows the drain electrodes 41D, source electrodes 41S, and gate electrodes 41G of the switching elements 411 to 418 to be electrically connected to the first surface electrodes 61A to 61H, the fourth surface electrode 64, and the third surface electrodes 63A to 63H without using wires. This prevents an increase in inductance due to wires.

[0247] (1-19) GaN HEMTs are used for the switching elements 411 to 418 of the drive circuits 40A to 40H. GaN HEMTs are transistors that are more suitable for high-speed operation than Si MOSFETs. Therefore, the pulse width of the laser light emitted by the semiconductor light emitting elements 30A to 30H can be shortened.

[0248] (1-20) Ceramic capacitors are used for the capacitors 421 to 428. This allows for a reduction in the cost of the semiconductor light emitting device 10 compared to when silicon capacitors are used for the capacitors 421 to 428.

[0249] 20 to 26, a semiconductor light emitting device 10 according to a second embodiment will be described. The semiconductor light emitting device 10 according to the second embodiment differs from the semiconductor light emitting device 10 according to the first embodiment mainly in the number of semiconductor light emitting elements, drive circuits, and protection diodes, and the configuration of the substrate 20. In the following, components common to the semiconductor light emitting device 10 according to the first embodiment are denoted by the same reference numerals, and their description will be omitted. In the second embodiment, the Y-axis direction is an example of the "first direction."

[0250] [Overall Configuration of Semiconductor Light-Emitting Device] The overall configuration of the semiconductor light-emitting device 10 of the second embodiment will be described with reference to FIGS. 20 to 24 . FIG. 20 schematically illustrates the planar structure of the semiconductor light-emitting device 10 of the second embodiment. FIG. 21 schematically illustrates an enlarged planar structure of the first partition region SP1 of FIG. 20 . FIG. 22 schematically illustrates the rear surface structure of the semiconductor light-emitting device 10 of FIG. 20 . FIG. 23 schematically illustrates a cross-sectional structure of the semiconductor light-emitting device 10 taken along line F23-F23 of FIG. 21 . FIG. 24 schematically illustrates a cross-sectional structure of the semiconductor light-emitting device 10 taken along line F24-F24 of FIG. 21 . Note that FIG. 22 is a perspective view to facilitate understanding of the correspondence between a first electrode layer 130A (described later) in FIG. 20 and a second electrode layer 130B (described later) in FIG. 22 . Furthermore, FIGS. 23 and 24 illustrate the semiconductor light-emitting element 30A in a simplified form to facilitate understanding of the drawings.

[0251] 20 , the semiconductor light emitting device 10 includes a substrate 120, one or more (four in the second embodiment) semiconductor light emitting elements 30A-30D, one or more (four in the second embodiment) drive circuits 40A-40D, and one or more (four in the second embodiment) protection diodes 70A-70D. The semiconductor light emitting device 10 is embodied as a multi-channel drive type light emitting module in which the plurality of semiconductor light emitting elements 30A-30D are driven by the plurality of drive circuits 40A-40D.

[0252] The semiconductor light emitting elements 30A-30D and a portion of each of the drive circuits 40A-40D are mounted on a substrate 120. The substrate 120 is a rectangular flat plate with its thickness direction in the Z-axis direction. The substrate 120 includes a first substrate surface 121, a second substrate surface 122 (see FIG. 23 ) opposite the first substrate surface 121, and first to fourth side surfaces 123-126 as four side surfaces connecting the first substrate surface 121 and the second substrate surface 122. The first side surface 123 and the second side surface 124 correspond to both end surfaces of the substrate 20 in the X-axis direction, and the third side surface 125 and the fourth side surface 126 correspond to both end surfaces of the substrate 20 in the Y-axis direction.

[0253] The substrate 120 includes a sealing resin 127 and a conductive portion 128 provided in the sealing resin 127. In the second embodiment, the substrate 120 includes a large number of wiring portions (i.e., circuit patterns) as the conductive portion 128, which are provided in the sealing resin 127 using, for example, a laser direct structuring (LDS) method. Therefore, the substrate 120 differs from one that uses a printed circuit board. At least a portion of the drive circuits 40A to 40D is embedded in the sealing resin 127. The conductive portion 128 forms a conductive path between the drive circuits 40A to 40D and the semiconductor light emitting elements 30A to 30D.

[0254] The sealing resin 127 contains a thermosetting insulating resin material and an additive. Examples of the insulating resin material are epoxy resin or polyimide resin. The additive contains a metal element that constitutes a part of the conductive portion 128. In the second embodiment, the material that constitutes the conductive portion 128 is Cu, and the additive contains Cu. However, the material that constitutes the conductive portion 128 is not limited to Cu.

[0255] The substrate 120 is configured as, for example, a multi-layer substrate. In the second embodiment, the substrate 120 is a two-layer substrate. Therefore, the conductive portion 128 includes a first electrode layer 130A provided on a first substrate surface 121 of the substrate 120 and a second electrode layer 130B (see FIG. 22 ) provided on a second substrate surface 122 of the substrate 120. The first substrate surface 121 of the substrate 120 corresponds to the main surface of the sealing resin 127, and the second substrate surface 122 of the substrate 120 corresponds to the back surface of the sealing resin 127. The detailed configuration of the conductive portion 128 will be described later.

[0256] As shown in Figure 23, the first substrate surface 121 of the substrate 120 is covered with a main surface resist layer 129A. The second substrate surface 122 of the substrate 120 is covered with a back surface resist layer 129B. The main surface resist layer 129A and the back surface resist layer 129B are made of an insulating material such as epoxy resin or polyimide resin. The main surface resist layer 129A and the back surface resist layer 129B may contain a filler such as silica or alumina. Note that in Figures 20 and 21, openings in the main surface resist layer 129A are indicated by two-dot chain lines. In Figure 22, openings in the back surface resist layer 129B are indicated by two-dot chain lines.

[0257] As shown in FIG. 20 , the semiconductor light emitting elements 30A to 30D are collectively arranged in a central region AC of the substrate 120. Here, the central region AC is a region including the center of the substrate 120 in a plan view. In one example, of the semiconductor light emitting elements 30A to 30D, the semiconductor light emitting elements 30A and 30B are arranged in a row in the X-axis direction within the central region AC. The remaining semiconductor light emitting elements 30C and 30D are arranged in a row in the X-axis direction, adjacent to the semiconductor light emitting elements 30A and 30B in the Y-axis direction. Therefore, the semiconductor light emitting elements 30A to 30D are arranged in a matrix adjacent to one another within the central region AC of the substrate 120. Note that the arrangement of the semiconductor light emitting elements 30A to 30D is arbitrary. In the semiconductor light emitting device 10 of the second embodiment, the semiconductor light emitting elements 30A to 30D are mounted on corresponding submount substrates 50, as in the first embodiment.

[0258] The drive circuits 40A to 40D drive the semiconductor light emitting elements 30A to 30D, respectively. Since the drive circuits 40A to 40D have the same configuration, the following description will focus on the drive circuit 40A, and detailed descriptions of the drive circuits 40B to 40D will be omitted.

[0259] 21 , the drive circuit 40A includes a switching element 411 and one or more capacitors 421. In the second embodiment, the drive circuit 40A includes one capacitor 421. The switching element 411 is mounted on the first substrate surface 121 of the substrate 120. The capacitor 421 is embedded in the sealing resin 127. The configuration of the switching element 411 is the same as in the first embodiment.

[0260] The capacitor 421 is provided near the switching element 411 in plan view. For example, the capacitor 421 is provided at a position adjacent to or near the switching element 411 in the Y-axis direction in plan view. The capacitor 421 is also provided at a position overlapping the semiconductor light emitting element 30A in plan view, for example, directly below the semiconductor light emitting element 30A.

[0261] For example, a silicon capacitor is used as the capacitor 421. Silicon capacitors are smaller than, for example, ceramic capacitors, and therefore it is easy to increase the capacitance per unit area of ​​the substrate. This allows the mounting area of ​​the capacitors 421 to 424 relative to the area of ​​the substrate 120 to be reduced, thereby enabling the miniaturization of the substrate 120 and, ultimately, the reduction in the module size of the semiconductor light-emitting device 10.

[0262] The capacitor 421 has a rectangular plate shape with its thickness oriented in the Z-axis direction. The capacitor 421 has a vertical structure. That is, the capacitor 421 includes a first electrode 42A and a second electrode 42B that face each other in the Z-axis direction. The first electrode 42A is located on a first surface (top surface in FIG. 23 ) of the capacitor 421, and the second electrode 42B is located on a second surface (bottom surface in FIG. 23 ) opposite the first surface of the capacitor 421.

[0263] Like drive circuit 40A, drive circuits 40B to 40D also include switching elements 412 to 414 configured similarly to switching element 411, and capacitors 422 to 424 configured similarly to capacitor 421. Like drive circuit 40A, drive circuit 40B also has, for example, one capacitor 422. This also applies to capacitors 423 and 424 of the other drive circuits 40C and 40D. Like drive circuit 40A, capacitors 422 to 424 of drive circuits 40B to 40D are also embedded in sealing resin 127.

[0264] 20, the drive circuits 40A-40D are arranged in a peripheral region AP of the substrate 120, which surrounds a central region AC of the substrate 120 in a plan view. That is, the drive circuits 40A-40D are arranged in the peripheral region AP, which is located outside the semiconductor light emitting elements 30A-30D in a plan view. The substrate 120 also includes first to fourth partition regions SP1-SP4, which are four wiring arrangement regions separated by two imaginary center lines VC and HC.

[0265] The drive circuits 40A to 40D are arranged in the peripheral regions AP of the first to fourth divided regions SP1 to SP4, respectively. In the second embodiment, the drive circuits 40A to 40D are arranged in the peripheral regions AP of the first to fourth divided regions SP1 to SP4, respectively, in a rotationally symmetric relationship. Therefore, the layout of the drive circuits 40B to 40D (switching elements 412 to 414 and capacitors 422 to 424) in the peripheral regions AP of the second to fourth divided regions SP1 to SP4 corresponds to the layout of the drive circuit 40A (switching element 411 and capacitor 421) in the peripheral region AP of the first divided region SP1 rotated clockwise by 90 degrees in a plan view. In the second embodiment, the protection diodes 70A to 70D also have a rotationally symmetric relationship. The protection diodes 70A to 70D are arranged in the peripheral regions AP of the first to fourth divided regions SP1 to SP4, respectively.

[0266] [Semiconductor Light-Emitting Device and Submount Substrate] Next, the configurations of the semiconductor light-emitting devices 30A to 30D and the submount substrate 50 will be described with reference to Figures 25 and 26. Figure 25 schematically shows the planar structure of the submount substrate 50. Figure 26 schematically shows the back surface structure of the submount substrate 50. The configurations of the semiconductor light-emitting devices 30A to 30D are similar to the configuration of the semiconductor light-emitting device 30A of the first embodiment.

[0267] 25 and 26 , the submount substrate 50 has a rectangular flat plate shape with its thickness direction in the Z-axis direction. The submount substrate 50 has a rectangular shape with long and short sides in a plan view. As in the first embodiment, the submount substrate 50 includes a base material 51, a substrate-side anode electrode 52, and a substrate-side cathode electrode 53. The submount substrate 50 of the second embodiment differs from the first embodiment in the configurations of the substrate-side anode electrode 52 and the substrate-side cathode electrode 53.

[0268] The first cathode electrode 53A of the substrate-side cathode electrode 53 is provided over substantially the entire base material 51 in a plan view. The first cathode electrode 53A has a rectangular shape that is slightly smaller than the base material 51 in a plan view. The first cathode electrode 53A includes an opening 53AA. The opening 53AA is provided at a position offset from the center of the submount substrate 50 in the long-side direction of the submount substrate 50 (the Y-axis direction in Figures 25 and 26). In one example, the opening 53AA has a circular shape in a plan view. Note that the shape of the opening 53AA in a plan view can be changed as desired. In one example, the area of ​​the first cathode electrode 53A is larger than the area of ​​the first anode electrode 52A in a plan view.

[0269] The first anode electrode 52A of the substrate-side anode electrode 52 is disposed within an opening 53AA of the first cathode electrode 53A. The first anode electrode 52A is disposed apart from the first cathode electrode 53A in a plan view. Therefore, the first anode electrode 52A is provided at a position offset from the center of the submount substrate 50 in the direction of the long side of the submount substrate 50. In one example, the first anode electrode 52A has a circular shape in a plan view.

[0270] As shown in FIG. 26 , the second anode electrode 52B and the second cathode electrode 53B are arranged side by side in the long-side direction of the submount substrate 50 (the Y-axis direction in FIG. 26 ). Both the second anode electrode 52B and the second cathode electrode 53B are rectangular in plan view. In the example shown in FIG. 26 , the second anode electrode 52B is rectangular in shape, with its long sides aligned with the long sides of the submount substrate 50 and its short sides aligned with the short sides of the submount substrate 50. The second cathode electrode 53B is rectangular in shape, with its long sides aligned with the short sides of the submount substrate 50 and its short sides aligned with the long sides of the submount substrate 50. In plan view, the area of ​​the second anode electrode 52B is larger than the area of ​​the second cathode electrode 53B.

[0271] The first via 52C of the substrate-side anode electrode 52 is provided at a position overlapping both the first anode electrode 52A and the second anode electrode 52B in a plan view. The number of the first via 52C is, for example, one, but there is no particular limitation on the number of the first via 52C.

[0272] The second vias 53C of the substrate-side cathode electrode 53 are provided at positions overlapping both the first cathode electrode 53A and the second cathode electrode 53B in a plan view. The second vias 53C are arranged in a matrix (e.g., 2 × 4).

[0273] 23 , the anode electrode 34 of the semiconductor light emitting element 30A is joined to the first anode electrode 52A by a conductive bonding material SD, and the cathode electrode 35 is joined to the first cathode electrode 53A by a conductive bonding material SD. Therefore, the semiconductor light emitting element 30A is positioned offset in the long side direction of the submount substrate 50 with respect to the submount substrate 50.

[0274] [Electrode Layer of Conductive Portion] Next, the first electrode layer 130A and the second electrode layer 130B of the conductive portion 128 will be described. As shown in Figures 20 and 22, the first electrode layer 130A is provided as a front electrode layer located on the first substrate surface 121 of the substrate 120, and the second electrode layer 130B is provided as a back electrode layer located on the second substrate surface 122 (see Figure 23) of the substrate 120. Both the first electrode layer 130A and the second electrode layer 130B are made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0275] 20 , the first electrode layer 130A includes a plurality of surface electrodes spaced apart from one another. In the second embodiment, the first electrode layer 130A includes first surface electrodes 131A to 131D, second surface electrodes 132A to 132D, third surface electrodes 133A to 133D, and fourth surface electrodes 134A to 134D. Here, the first surface electrodes 131A to 131D are an example of "surface-side anode electrodes," and the second surface electrodes 132A to 132D are an example of "surface-side cathode electrodes."

[0276] The first surface electrodes 131A to 131D, the second surface electrodes 132A to 132D, the third surface electrodes 133A to 133D, and the fourth surface electrodes 134A to 134D are used to mount the semiconductor light emitting elements 30A to 30D, the switching elements 411 to 414 of the drive circuits 40A to 40D, and the protection diodes 70A to 70D.

[0277] Each of the first surface electrodes 131A-131D is disposed across both the central region AC and the peripheral region AP. The first surface electrodes 131A-131D include adjacent portions within the central region AC that serve as mounting surfaces for the semiconductor light emitting elements 30A-30D using the submount substrate 50. Furthermore, the first surface electrodes 131A-131D also include portions that are rotationally symmetrically disposed in the peripheral regions AP of the first to fourth divided regions SP1-SP4, respectively. The portions of the first surface electrodes 131A-131D that are disposed in the peripheral regions AP of the first to fourth divided regions SP1-SP4 are used to mount the protection diodes 70A-70D.

[0278] The second surface electrodes 132A-132D are respectively arranged in the peripheral areas AP of the first to fourth divided areas SP1-SP4, adjacent to the first surface electrodes 131A-131D, the third surface electrodes 133A-133D, and the fourth surface electrodes 134A-134D. The second surface electrodes 132A-132D are respectively arranged in the peripheral areas AP of the first to fourth divided areas SP1-SP4 in a rotationally symmetric relationship. The second surface electrodes 132A-132D are used to mount the semiconductor light emitting elements 30A-30D using the submount substrate 50, and to mount the switching elements 411-414 and the protection diodes 70A-70D.

[0279] Semiconductor light emitting element 30A is mounted on first surface electrode 131A and second surface electrode 132A using a submount substrate 50. As a result, the anode electrode 34 of semiconductor light emitting element 30A is electrically connected to first surface electrode 131A through submount substrate 50, and the cathode electrode 35 is electrically connected to second surface electrode 132A through submount substrate 50. Similar to semiconductor light emitting element 30A, semiconductor light emitting elements 30B to 30D are also mounted on first surface electrodes 131B to 131D and second surface electrodes 132B to 132D, respectively, using submount substrate 50.

[0280] The protection diode 70A is mounted across both the first surface electrode 131A and the second surface electrode 132A. In the second embodiment, as shown in Fig. 24, the anode electrode 71 of the protection diode 70A is joined to the second surface electrode 132A with a conductive bonding material (not shown), and the cathode electrode 72 is joined to the first surface electrode 131A with a conductive bonding material (not shown). Like the protection diode 70A, the protection diodes 70B to 70D are also mounted on the first surface electrodes 131B to 131D and the second surface electrodes 132B to 132D, respectively.

[0281] Therefore, the cathode electrodes 72 of the protection diodes 70A to 70D are electrically connected to the anode electrodes 34 of the semiconductor light emitting elements 30A to 30D, and the anode electrodes 71 of the protection diodes 70A to 70D are electrically connected to the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30D. In other words, the protection diodes 70A to 70D are connected in anti-parallel to the semiconductor light emitting elements 30A to 30D, respectively.

[0282] Each of the first surface electrodes 131A to 131D is rectangular with long and short sides. A semiconductor light emitting element 30A mounted on a submount substrate 50 and a protection diode 70A are aligned on the first surface electrode 131A and the second surface electrode 132A in the direction of the long side of the first surface electrode 131A. The semiconductor light emitting elements 30B to 30D and the protection diodes 70B to 70D on the first surface electrodes 131B to 131D are arranged in the same manner as the semiconductor light emitting element 30A and the protection diode 70A.

[0283] The third surface electrodes 133A to 133D are arranged in the peripheral areas AP of the first to fourth divided areas SP1 to SP4, respectively, adjacent to the second surface electrodes 132A to 132D and the fourth surface electrodes 134A to 134D. The third surface electrodes 133A to 133D are arranged in the peripheral areas AP of the first to fourth divided areas SP1 to SP4, respectively, in a rotationally symmetric relationship. The third surface electrodes 133A to 133D are used to mount the switching elements 411 to 414.

[0284] The fourth surface electrodes 134A to 134D are arranged in the peripheral areas AP of the first to fourth divided areas SP1 to SP4, respectively, adjacent to the second surface electrodes 132A to 132D and the third surface electrodes 133A to 133D. The fourth surface electrodes 134A to 134D are arranged in the peripheral areas AP of the first to fourth divided areas SP1 to SP4, respectively, in a rotationally symmetric relationship. The fourth surface electrodes 134A to 134D are used to mount the switching elements 411 to 414.

[0285] 21 , the switching element 411 is disposed at a distance from the semiconductor light emitting element 30A (submount substrate 50) in the short side direction (the Y-axis direction in FIG. 21 ) of the first surface electrode 131A. When viewed from the short side direction, the switching element 411 is disposed at a position overlapping with the semiconductor light emitting element 30A (submount substrate 50).

[0286] The drain electrode 41D of the switching element 411 is mounted on the second surface electrode 132A, the gate electrode 41G is mounted on the third surface electrode 133A, and the source electrode 41S is mounted on the fourth surface electrode 134A. As shown in FIG. 23 , the drain electrode 41D is bonded to the second surface electrode 132A with a conductive bonding material SD. Although not shown, the gate electrode 41G and the source electrode 41S are also bonded to the third surface electrode 133A and the fourth surface electrode 134A, respectively, with a conductive bonding material SD. Like the switching element 411, the switching elements 412 to 414 are also mounted on the second surface electrodes 132B to 132D, the third surface electrodes 133B to 133D, and the fourth surface electrodes 134B to 134D, respectively.

[0287] 22 , the second electrode layer 130B, which is the back electrode layer, includes a plurality of back electrodes (pattern electrodes) spaced apart from one another. These back electrodes function as external electrode terminals that are electrically connected to a circuit board (not shown) when the semiconductor light emitting device 10 is mounted on the circuit board. In the second embodiment, the second electrode layer 130B includes a first back electrode 141, second back electrodes 142A to 142D, and third back electrodes 143A to 143D.

[0288] The first back surface electrode 141 is disposed across both the central region AC and the peripheral region AP of the substrate 120. The first back surface electrode 141 is provided at a position overlapping the capacitors 421 to 424, the first surface electrodes 131A to 131D, and the fourth surface electrodes 134A to 134D (see FIG. 20 for all of these) in a plan view. The first back surface electrode 141 is provided for electrical connection with the second electrodes 42B (see FIG. 23) of the capacitors 421 to 424 embedded in the sealing resin 127 and the fourth surface electrodes 134A to 134D. The first back surface electrode 141 functions as a ground terminal that supplies a ground voltage.

[0289] The second back surface electrodes 142A to 142D are disposed in the peripheral regions AP of the first to fourth divided regions SP1 to SP4, respectively. The second back surface electrodes 142A to 142D are provided at positions overlapping the third surface electrodes 133A to 133D, respectively, in a plan view. The second back surface electrodes 142A to 142D are provided for electrical connection with the third surface electrodes 133A to 133D. The second back surface electrodes 142A to 142D function as signal terminals that supply gate voltage signals.

[0290] The third back surface electrodes 143A to 143D are arranged in the peripheral regions AP of the first to fourth divided regions SP1 to SP4, respectively. The third back surface electrodes 143A to 143D are provided at positions overlapping the first surface electrodes 131A to 131D, respectively, in a plan view. The third back surface electrodes 143A to 143D are provided for electrical connection with the first surface electrodes 131A to 131D. The third back surface electrodes 143A to 143D function as power supply terminals that supply a power supply voltage.

[0291] [Connection Structure Between Semiconductor Light Emitting Elements and Drive Circuits] The conductive portion 128 includes a plurality of vias (connection conductors) that electrically connect the semiconductor light emitting elements 30A-30D, the switching elements 411-414 and capacitors 421-424 of the drive circuits 40A-40D, and the first electrode layer 130A and the second electrode layer 130B. In the second embodiment, the conductive portion 128 includes first to fifth vias 151-155. Each of the first to fifth vias 151-155 is made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0292] As shown in FIGS. 21 to 24 , the first vias 151 are disposed in the sealing resin 127 at positions overlapping the semiconductor light emitting element 30A, the first surface electrode 131A, and the first electrode 42A of the capacitor 421 in a plan view. The first vias 151 penetrate the sealing resin 127 from the first surface electrode 131A to the first electrode 42A of the capacitor 421, thereby connecting the first surface electrode 131A and the first electrode 42A of the capacitor 421. The first surface electrode 131A is electrically connected to the anode electrode 34 of the semiconductor light emitting element 30A. Therefore, the anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the first electrode 42A of the capacitor 421. The number of first vias 151 is not particularly limited and may be one or more. In the second embodiment, the first vias 151 are arranged in a matrix (e.g., 2×2). The other first vias 151 connecting the first surface electrodes 131B to 131D and the first electrodes 42A of the capacitors 422 to 424 are similarly configured and arranged.

[0293] The second via 152 is disposed within the sealing resin 127 at a position overlapping both the fourth surface electrode 134A and the first back surface electrode 141 in a plan view. The second via 152 penetrates the sealing resin 127 from the fourth surface electrode 134A to the first back surface electrode 141, thereby connecting the fourth surface electrode 134A and the first back surface electrode 141. The fourth surface electrode 134A is connected to the source electrode 41S of the switching element 411, and the first back surface electrode 141 is provided as a ground terminal. Therefore, the source electrode 41S of the switching element 411 is connected to ground. The number of second vias 152 is not particularly limited and may be one or more. In the second embodiment, the second vias 152 are disposed in a matrix (e.g., 2 × 4). The other second vias 152 connecting the fourth surface electrodes 134B to 134D and the first back surface electrode 141 are similarly configured and disposed.

[0294] The third via 153 is disposed within the sealing resin 127 at a position overlapping both the third surface electrode 133A and the second back surface electrode 142A in a plan view. The third via 153 penetrates the sealing resin 127 from the third surface electrode 133A to the second back surface electrode 142A, connecting the third surface electrode 133A and the second back surface electrode 142A. The third surface electrode 133A is connected to the gate electrode 41G of the switching element 411, and the second back surface electrode 142A serves as a signal terminal for supplying a gate voltage signal. Therefore, during operation of the semiconductor light-emitting device 10, a gate voltage signal is supplied to the gate electrode 41G of the switching element 411. The other third vias 153 connecting the third surface electrodes 133B-133D and the second back surface electrodes 142B-142D are similarly configured and disposed. Therefore, during operation of the semiconductor light-emitting device 10, a gate voltage signal is supplied to the gate electrodes 41G of the switching elements 412-414.

[0295] The fourth via 154 is disposed within the sealing resin 127 at a position overlapping both the first surface electrode 131A and the third back surface electrode 143A in a plan view. The fourth via 154 penetrates the sealing resin 127 from the first surface electrode 131A to the third back surface electrode 143A, connecting the first surface electrode 131A and the third back surface electrode 143A. The first surface electrode 131A is electrically connected to the first electrode 42A of the capacitor 421, and the third back surface electrode 143A serves as a power supply terminal. Thus, when the switching element 411 is in the off state during operation of the semiconductor light-emitting device 10, charge based on the power supply voltage is accumulated in the capacitor 421. The number of fourth vias 154 is not particularly limited and may be one or more. In the second embodiment, the fourth vias 154 are arranged in a matrix (e.g., 2 × 3). The other fourth vias 154 connecting the first front electrodes 131B to 131D and the third back electrodes 143B to 143D are configured and arranged in a similar manner. Therefore, when the switching elements 412 to 414 are in the off state during operation of the semiconductor light emitting device 10, electric charges based on the power supply voltage are accumulated in the capacitors 422 to 424, respectively.

[0296] As shown in FIGS. 22 to 24 , the fifth via 155 is disposed within the sealing resin 127 at a position overlapping both the second electrode 42B and the first back surface electrode 141 of the capacitor 421 in a plan view. The fifth via 155 penetrates the sealing resin 127 from the second electrode 42B of the capacitor 421 to the first back surface electrode 141, thereby connecting the second electrode 42B of the capacitor 421 to the first back surface electrode 141. Therefore, the second electrode 42B of the capacitor 421 is connected to ground. The number of fifth vias 155 is not particularly limited and may be one or more. The other fifth vias 155 connecting the second electrodes 42B of the capacitors 422 to 424 to the first back surface electrode 141 are similarly configured and disposed. As a result, the second electrodes 42B of the capacitors 422 to 424 are each connected to ground.

[0297] [Current Path of Semiconductor Light-Emitting Device] The current path between the drive circuit 40A and the semiconductor light-emitting element 30A is configured in the shape of a loop, with current flowing in the following order: first electrode 42A of capacitor 421, first via 151, first surface electrode 131A of the first electrode layer 130A, substrate-side anode electrode 52 of the submount substrate 50, anode electrode 34 of the semiconductor light-emitting element 30A, cathode electrode 35 of the semiconductor light-emitting element 30A, substrate-side cathode electrode 53 of the submount substrate 50, second surface electrode 132A of the first electrode layer 130A, drain electrode 41D of the switching element 411, source electrode 41S of the switching element 411, fourth surface electrode 134A of the first electrode layer 130A, second via 152, first back surface electrode 141 of the second electrode layer 130B, fifth via 155, and second electrode 42B of capacitor 421.

[0298] In addition, since the same electrical connections as between the drive circuit 40A and the semiconductor light-emitting element 30A are realized for the other drive circuits 40B to 40D and the other semiconductor light-emitting elements 30B to 30D, loop-shaped current paths similar to the current path between the drive circuit 40A and the semiconductor light-emitting element 30A are individually configured.

[0299] [Circuit Configuration of Semiconductor Light-Emitting Device] A light-emitting system 300 including the semiconductor light-emitting device 10 has a configuration in which the number of backflow prevention diodes, gate drivers, pulse generators, control power supplies, semiconductor light-emitting elements, drive circuits, and protection diodes is reduced compared to, for example, the light-emitting system 300 of the first embodiment. That is, the light-emitting system 300 includes backflow prevention diodes 304A-304D, gate drivers 305A-305D, pulse generators 306A-306D, control power supplies 307A-307D, semiconductor light-emitting elements 30A-30D, drive circuits 40A-40D, and protection diodes 70A-70D. The circuit configuration of the light-emitting system 300 of the second embodiment is similar to that of the first embodiment.

[0300] Effects of the Second Embodiment The semiconductor light emitting device 10 of the second embodiment has the following effects: (2-1) The capacitors 421 to 424 of the drive circuits 40A to 40D are embedded in the sealing resin 127 at positions that overlap the semiconductor light emitting elements 30A to 30D, respectively, in a plan view.

[0301] This configuration allows for a reduction in the size of the semiconductor light-emitting device 10. In addition, the distance between the capacitors 421-424 and the semiconductor light-emitting elements 30A-30D can be shortened, thereby shortening the current paths between the semiconductor light-emitting elements 30A-30D and the drive circuits 40A-40D. This reduces the inductance caused by the length of the current paths.

[0302] (2-2) Silicon capacitors are used for the capacitors 421 to 424. Silicon capacitors are smaller than ceramic capacitors, making it easier to increase the capacitance per unit area of ​​the substrate. This allows the mounting area of ​​the capacitors 421 to 424 relative to the area of ​​the substrate 20 to be reduced, thereby enabling the miniaturization of the substrate 20 and, in turn, the semiconductor light-emitting device 10.

[0303] 27 to 39, a semiconductor light emitting device 10 according to a third embodiment will be described. The semiconductor light emitting device 10 according to the third embodiment differs from the semiconductor light emitting device 10 according to the second embodiment mainly in the configuration and arrangement of the switching elements 411 to 414 of the drive circuits 40A to 40D. In the following, components common to the semiconductor light emitting device 10 according to the second embodiment are designated by the same reference numerals, and their description will be omitted.

[0304] [Overall Configuration of Semiconductor Light-Emitting Device] The overall configuration of the semiconductor light-emitting device 10 will be described with reference to FIGS. 27 to 33. FIG. 27 schematically illustrates the planar structure of the semiconductor light-emitting device 10 of the third embodiment. FIG. 28 schematically illustrates an enlarged planar structure of the first partitioned region SP1 in FIG. 27. FIG. 29 schematically illustrates the rear surface structure of the semiconductor light-emitting device 10. FIG. 30 schematically illustrates the cross-sectional structure of the semiconductor light-emitting device 10 taken along line F30-F30 in FIG. 28. FIG. 31 schematically illustrates the cross-sectional structure of the semiconductor light-emitting device 10 taken along line F31-F31 in FIG. 28. FIG. 32 schematically illustrates the planar structure of the submount substrate 50. FIG. 33 schematically illustrates the rear surface structure of the submount substrate 50. Note that FIG. 29 illustrates a perspective view to facilitate understanding of the correspondence between the first electrode layer 130A in FIG. 27 and the second electrode layer 130B in FIG. 29. 30 and 31, the semiconductor light emitting element 30A is shown in a simplified form to facilitate understanding of the drawings.

[0305] As shown in FIG. 27, the semiconductor light emitting device 10 includes a substrate 120, semiconductor light emitting elements 30A to 30D, drive circuits 40A to 40D, and protection diodes 70A to 70D, similar to the second embodiment.

[0306] The semiconductor light emitting elements 30A to 30D are mounted on first surface electrodes 161A to 161D and second surface electrodes 162A to 162D (described later) of the first electrode layer 130A using a submount substrate 50. The semiconductor light emitting elements 30A to 30D are collectively arranged in a central region AC. The arrangement of the semiconductor light emitting elements 30A to 30D is the same as in the second embodiment.

[0307] 32 and 33 , the submount substrate 50 differs from the submount substrate 50 of the second embodiment in the shapes of the second anode electrode 52B and the second cathode electrode 53B. More specifically, as shown in FIG. 33 , the second anode electrode 52B is rectangular, with its short sides aligned with the long side of the submount substrate 50 and its long sides aligned with the short side of the submount substrate 50. The dimension of the second cathode electrode 53B in the long side direction of the submount substrate 50 is larger than in the second embodiment. In the third embodiment, the area of ​​the second anode electrode 52B is smaller than the area of ​​the second cathode electrode 53B in a plan view.

[0308] 27, each of the drive circuits 40A to 40D is arranged in the peripheral area AP. The switching elements 411 to 414 and capacitors 421 to 424 of the drive circuits 40A to 40D are respectively arranged in the sealing resin 127. The protection diodes 70A to 70D are respectively mounted on the first surface electrodes 161A to 161D and the second surface electrodes 162A to 162D, as in the second embodiment.

[0309] As shown in FIG. 28 , the switching element 411 is provided near the semiconductor light emitting element 30A in a plan view. The switching element 411 is provided, for example, at a position adjacent to or close to the semiconductor light emitting element 30A in the Y-axis direction. The switching element 411 has a rectangular shape in a plan view. In the third embodiment, the switching element 411 has a square shape, for example. Note that the shape of the switching element 411 in a plan view can be changed as desired. For example, a vertical transistor is used as the switching element 411. Examples of such vertical transistors include a metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), and a bipolar transistor. In the third embodiment, for example, an n-type MOSFET is used as the switching element 411.

[0310] As shown in FIG. 30 , the switching element 411 includes a first element surface 41A (top surface in FIG. 30 ) and a second element surface 41B (bottom surface in FIG. 30 ) opposite the first element surface 41A. The switching element 411 also includes a drain electrode 41D provided on the first element surface 41A, and a source electrode 41S and a gate electrode 41G provided on the second element surface 41B. The drain electrode 41D is provided, for example, over the entire surface of the first element surface 41A. The source electrode 41S is provided, for example, over most of the second element surface 41B. The gate electrode 41G is located, for example, near one corner of the second element surface 41B (see FIG. 29 ).

[0311] [Electrode Layers of Conductive Portion of Substrate] Next, the first electrode layer 130A and the second electrode layer 130B of the conductive portion 128 of the substrate 120 will be described. As shown in Figures 27 and 29, the first electrode layer 130A is provided as a front electrode layer located on the first substrate surface 121 of the substrate 120. The second electrode layer 130B is provided as a back electrode layer located on the second substrate surface 122 of the substrate 120.

[0312] [First Electrode Layer (Surface Electrode Layer)] As shown in FIG. 27 , the first electrode layer 130A includes a plurality of surface electrodes (pattern electrodes) spaced apart from one another. In the third embodiment, the first electrode layer 130A includes first surface electrodes 161A to 161D and second surface electrodes 162A to 162D. Each of the first surface electrodes 161A to 161D and the second surface electrodes 162A to 162D is made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W. Here, the first surface electrodes 161A to 161D are an example of a "surface-side anode electrode," and the second surface electrodes 162A to 162D are an example of a "surface-side cathode electrode."

[0313] The first surface electrodes 161A-161D and the second surface electrodes 162A-162D are used to mount the semiconductor light emitting elements 30A-30D and the protection diodes 70A-70D. That is, the first electrode layer 130A includes the mounting surfaces for the semiconductor light emitting elements 30A-30D and the protection diodes 70A-70D. On the other hand, the first electrode layer 130A does not include the mounting surfaces for the drive circuits 40A-40D.

[0314] Each of the first surface electrodes 161A-161D has an elongated rectangular shape in a plan view. The first surface electrodes 161A-161D are provided across both the central region AC and the peripheral region AP. The first surface electrodes 161A-161D include adjacent portions within the central region AC that serve as mounting surfaces for the semiconductor light emitting elements 30A-30D. The first surface electrodes 161A-161D also include portions that are rotationally symmetrically arranged in the peripheral regions AP of the first to fourth divided regions SP1-SP4, respectively. The portions of the first surface electrodes 161A-161D that are arranged in the peripheral regions AP of the first to fourth divided regions SP1-SP4, respectively, are used to mount the protection diodes 70A-70D.

[0315] As shown in FIGS. 30 and 31 , the semiconductor light emitting element 30A is mounted on a first surface electrode 161A and a second surface electrode 162A using a submount substrate 50. In the third embodiment, the second anode electrode 52B of the submount substrate 50 is bonded to the first surface electrode 161A with a conductive bonding material SD. The second cathode electrode 53B of the submount substrate 50 is bonded to the second surface electrode 162A with a conductive bonding material SD. As a result, the anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the first surface electrode 161A. The cathode electrode 35 of the semiconductor light emitting element 30A is electrically connected to the second surface electrode 162A. Note that, like the semiconductor light emitting element 30A, the semiconductor light emitting elements 30B to 30D are also mounted on the first surface electrodes 161B to 161D and the second surface electrodes 162B to 162D using the submount substrate 50.

[0316] The protection diode 70A is mounted across both the first surface electrode 161A and the second surface electrode 162A. The anode electrode 71 of the protection diode 70A is joined to the second surface electrode 162A by a conductive bonding material (not shown). The cathode electrode 72 of the protection diode 70A is joined to the first surface electrode 161A by a conductive bonding material (not shown). Like the protection diode 70A, the protection diodes 70B to 70D are also mounted on the first surface electrodes 161B to 161D and the second surface electrodes 162B to 162D, respectively. Therefore, the protection diodes 70A to 70D are connected in anti-parallel to the semiconductor light emitting elements 30A to 30D, respectively.

[0317] 29 , the second electrode layer 130B includes a plurality of rear surface electrodes (pattern electrodes) spaced apart from one another. In the third embodiment, the second electrode layer 130B includes a first rear surface electrode 171, second rear surface electrodes 172A to 172D, and third rear surface electrodes 173A to 173D. Each of the first rear surface electrode 171, second rear surface electrodes 172A to 172D, and third rear surface electrodes 173A to 173D is made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0318] The first back surface electrode 171 is provided across both the central region AC and the peripheral region AP of the substrate 120. The first back surface electrode 171 is provided so as to overlap the capacitors 421-424, the first surface electrodes 161A-161D, the switching elements 411-414, and the second surface electrodes 162A-162D in a plan view. The first back surface electrode 171 is provided for electrical connection with the source electrodes 41S (see FIG. 30) of the switching elements 411-414 and the second electrodes 42B (see FIG. 30) of the capacitors 421-424, which are embedded in the sealing resin 127. The first back surface electrode 171 includes four openings provided at positions overlapping the gate electrodes 41G (see FIG. 30) of the switching elements 411-414 in a plan view. The first back surface electrode 171 functions as a ground terminal for supplying a ground voltage.

[0319] The second back-surface electrodes 172A to 172D are arranged in the peripheral region AP of the first to fourth divided regions SP1 to SP4, respectively. The second back-surface electrodes 172A to 172D are arranged at positions overlapping the gate electrodes 41G of the switching elements 411 to 414 in a plan view. The second back-surface electrodes 172A to 172D are provided for electrical connection to the gate electrodes 41G of the switching elements 411 to 414 embedded in the sealing resin 127. The second back-surface electrodes 172A to 172D are arranged in four openings in the first back-surface electrode 171. The second back-surface electrodes 172A to 172D function as signal terminals that supply gate voltage signals.

[0320] The third back surface electrodes 173A to 173D are disposed in the peripheral regions AP of the first partition regions SP1 to SP4, respectively. The third back surface electrodes 173A to 173D are provided at positions overlapping the first surface electrodes 161A to 161D, respectively, in a plan view. In the third embodiment, the third back surface electrodes 173A to 173D are provided at positions overlapping the second surface electrodes 162A to 162D, respectively, in a plan view. Note that the third back surface electrodes 173A to 173D do not necessarily overlap the second surface electrodes 162A to 162D, respectively, in a plan view. The third back surface electrodes 173A to 173D are provided for electrical connection with the first surface electrodes 161A to 161D. The third back surface electrodes 173A to 173D function as power supply terminals that supply power supply voltage.

[0321] [Connection Structure Between Semiconductor Light Emitting Elements and Drive Circuits] The conductive portion 128 includes a plurality of vias (connection conductors) that electrically connect the semiconductor light emitting elements 30A-30D, the switching elements 411-414 and capacitors 421-424 of the drive circuits 40A-40D, the first electrode layer 130A, and the second electrode layer 130B. In the third embodiment, the conductive portion 128 includes first to sixth vias 181-186. The first to sixth vias 181-186 are made of one or more materials selected from the group including, for example, Ti, TiN, Au, Ag, Cu, Al, and W.

[0322] 30 and 31 , the first via 181 is disposed in the sealing resin 127 at a position overlapping the semiconductor light emitting element 30A, the first surface electrode 161A, and the first electrode 42A of the capacitor 421 in a plan view. The first via 181 penetrates the sealing resin 127 from the first surface electrode 161A to the first electrode 42A of the capacitor 421, thereby connecting the first surface electrode 161A and the first electrode 42A of the capacitor 421. Therefore, the anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the first electrode 42A of the capacitor 421.

[0323] The number of first vias 181 is not particularly limited and may be one or more. In the third embodiment, for example, a plurality of first vias 181 are arranged in a matrix (e.g., 2 x 2) in a region where the semiconductor light emitting element 30A, the first surface electrode 161A, and the first electrode 42A of the capacitor 421 overlap. Note that the other first vias 181 connecting the first electrodes 42A of the capacitors 422 to 424 to the first surface electrodes 161B to 161D are similarly configured and arranged.

[0324] 28 and 30 , the second via 182 is disposed in the sealing resin 127 at a position overlapping both the second surface electrode 162A and the drain electrode 41D of the switching element 411 in a plan view. The second via 182 penetrates the sealing resin 127 from the second surface electrode 162A to the drain electrode 41D of the switching element 411, thereby connecting the second surface electrode 162A to the drain electrode 41D of the switching element 411. The second surface electrode 162A is electrically connected to the cathode electrode 35 of the semiconductor light emitting element 30A. Therefore, the cathode electrode 35 of the semiconductor light emitting element 30A is electrically connected to the drain electrode 41D of the switching element 411.

[0325] The number of second vias 182 is not particularly limited and may be one or more. In the third embodiment, for example, a plurality of second vias 182 are arranged in a matrix (e.g., 3 x 3) in the region where the second surface electrode 162A and the drain electrode 41D of the switching element 411 overlap. Note that the other second vias 182 connecting the second surface electrodes 162B to 162D and the drain electrodes 41D of the switching elements 412 to 414 are similarly configured and arranged.

[0326] 28 and 31 , the third via 183 is disposed in the sealing resin 127 at a position overlapping both the first surface electrode 161A and the third back surface electrode 173A in a plan view. The third via 183 penetrates the sealing resin 127 from the first surface electrode 161A to the third back surface electrode 173A, thereby connecting the first surface electrode 161A and the third back surface electrode 173A. The third back surface electrode 173A is provided as a power supply terminal. The first surface electrode 161A is electrically connected to the first electrode 42A of the capacitor 421. As a result, when the switching element 411 is in the off state during operation of the semiconductor light-emitting device 10, charge based on the power supply voltage is accumulated in the capacitor 421.

[0327] The number of third vias 183 is not particularly limited and may be one or more. In the third embodiment, for example, a plurality of third vias 183 are arranged in a matrix (e.g., 2 x 3) in the region where the first surface electrode 161A and the third back surface electrode 173A overlap. Note that the other third vias 183 connecting the first surface electrodes 161B to 161D and the third back surface electrodes 173B to 173D are configured and arranged in a similar manner.

[0328] 28 and 30 , the fourth via 184 is disposed in the sealing resin 127 at a position overlapping the second electrode 42B and the first back surface electrode 171 of the capacitor 421 in a plan view. The fourth via 184 penetrates the sealing resin 127 from the second electrode 42B of the capacitor 421 to the first back surface electrode 171, thereby connecting the second electrode 42B of the capacitor 421 to the first back surface electrode 171. The first back surface electrode 171 is provided as a ground terminal. Therefore, the second electrode 42B of the capacitor 421 is connected to ground.

[0329] The number of fourth vias 184 is not particularly limited and may be one or more. In the third embodiment, for example, a plurality of fourth vias 184 are arranged in a matrix (for example, 2×2) in the region where the capacitor 421 and the first back surface electrode 171 overlap. Note that the other fourth vias 184 connecting the second electrodes 42B of the capacitors 422 to 424 and the first back surface electrode 171 are configured and arranged in a similar manner.

[0330] The fifth via 185 is disposed in the sealing resin 127 at a position overlapping the source electrode 41S of the switching element 411 and the first back surface electrode 171 in a plan view. The fifth via 185 penetrates the sealing resin 127 from the source electrode 41S of the switching element 411 to the first back surface electrode 171, thereby connecting the source electrode 41S of the switching element 411 to the first back surface electrode 171. Therefore, the source electrode 41S of the switching element 411 is connected to ground.

[0331] The number of fifth vias 185 is not particularly limited and may be one or more. In the third embodiment, for example, a plurality of (for example, six) fifth vias 185 are arranged in a region where the source electrode 41S of the switching element 411 overlaps with the first back surface electrode 171. Note that the other fifth vias 185 connecting the source electrodes 41S of the switching elements 412 to 414 with the first back surface electrode 171 are similarly configured and arranged.

[0332] The sixth via 186 is disposed in the sealing resin 127 at a position overlapping the second back surface electrode 172A and the gate electrode 41G of the switching element 411 in a plan view. The sixth via 186 penetrates the sealing resin 127 from the gate electrode 41G of the switching element 411 to the second back surface electrode 172A, thereby connecting the gate electrode 41G of the switching element 411 to the second back surface electrode 172A. This allows a gate voltage signal to be supplied to the gate electrode 41G of the switching element 411. The other sixth vias 186 connecting the gate electrodes 41G of the switching elements 412 to 414 to the second back surface electrodes 172B to 172D are similarly configured and disposed. This allows a gate voltage signal to be supplied to each of the gate electrodes 41G of the switching elements 412 to 414.

[0333] [Current Path of Semiconductor Light-Emitting Device] The current path between the drive circuits 40A-40D and the semiconductor light-emitting elements 30A-30D is formed by the conductive portion 128 of the substrate 120. In the third embodiment, the current path is configured in a loop shape in which current flows in the following order: the first electrode 42A of the capacitor 421, the first via 181, the first surface electrode 161A of the first electrode layer 130A, the substrate-side anode electrode 52 of the submount substrate 50, the anode electrode 34 of the semiconductor light-emitting element 30A, the cathode electrode 35 of the semiconductor light-emitting element 30A, the substrate-side cathode electrode 53 of the submount substrate 50, the second surface electrode 162A of the first electrode layer 130A, the second via 182, the drain electrode 41D of the switching element 411, the source electrode 41S of the switching element 411, the fifth via 185, the first back surface electrode 171 of the second electrode layer 130B, the fourth via 184, and the second electrode 42B of the capacitor 421.

[0334] Note that the drive circuits 40B to 40D and the semiconductor light emitting elements 30B to 30D are electrically connected in the same manner as the drive circuit 40A and the semiconductor light emitting element 30A. Therefore, the drive circuits 40B to 40D and the semiconductor light emitting elements 30B to 30D are individually configured with loop-shaped current paths similar to the current path between the drive circuit 40A and the semiconductor light emitting element 30A.

[0335] [Method of Manufacturing Semiconductor Light-Emitting Device] Next, an exemplary method of manufacturing semiconductor light-emitting device 10 will be described with reference to Figures 34 to 39. In order to facilitate understanding of the correspondence between the method of manufacturing semiconductor light-emitting device 10 and the configuration of semiconductor light-emitting device 10, a method of manufacturing semiconductor light-emitting device 10 corresponding to the structure of Figure 30 taken along line F30-F30 in Figure 28 will be described below, and in Figures 34 to 39, components that are the same as those shown in Figure 30 are given the same reference numerals.

[0336] 34, the method for manufacturing the semiconductor light-emitting device 10 includes holding the switching element 411 and the capacitor 421 on the support member 200. At this time, the switching element 411 and the capacitor 421 are in a position that is upside down from that shown in FIG.

[0337] As shown in Figure 35, the manufacturing method for the semiconductor light-emitting device 10 includes forming a resin layer 127A on a support member 200 to cover the switching element 411 and the capacitor 421. The resin layer 127A is a layer that forms part of the sealing resin 127 in Figure 30 and contains a thermosetting insulating resin material and an additive containing a metal element that constitutes part of the conductive portion 128. The insulating resin material is, for example, an epoxy resin or a polyimide resin. The resin layer 127A is formed by, for example, compression molding. After molding the resin layer 127A, the support member 200 is removed.

[0338] 36 , the semiconductor light emitting device 10 includes forming vias and a back surface electrode in the resin layer 127A. More specifically, this process forms a fourth via 184 connected to the capacitor 421, a fifth via 185 and a sixth via 186 connected to the switching element 411, a first back surface electrode 171 connected to the fourth via 184 and the fifth via 185, and a second back surface electrode 172A connected to the sixth via 186.

[0339] In the process shown in FIG. 36 , a laser is irradiated onto the resin layer 127A to deposit foundation layers for the first back surface electrode 171 and the second back surface electrode 172A and for the fourth to sixth vias 184 to 186. The foundation layers for the fourth to sixth vias 184 to 186 are deposited on the wall surfaces of the through holes (via holes) formed by the laser irradiation. These foundation layers are composed of metal elements contained in an additive contained in the resin layer 127A. The metal elements are excited by the laser irradiation, causing a metal layer containing the metal elements to deposit as the foundation layer. Next, a plating layer is formed to cover these foundation layers. This plating layer is formed from the material of the conductive portion 128 (e.g., a material containing Cu). The plating layer is formed, for example, by electroless plating. As a result, as shown in FIG. 36 , the first back surface electrode 171, the second back surface electrode 172A, and the fourth to sixth vias 184 to 186 are formed by the foundation layer and the plating layer covering it. In the step shown in FIG. 36, other second rear surface electrodes 172B to 172D and other fourth to sixth vias 184 to 186 are formed through laser irradiation and electroless plating using the same techniques as those described above.

[0340] As shown in FIG. 37 , the manufacturing method for the semiconductor light-emitting device 10 includes inverting the structure of FIG. 36 and holding it on a support member 210. Next, as shown in FIG. 38 , the manufacturing method for the semiconductor light-emitting device 10 includes forming a resin layer 127B that covers the resin layer 127A, the switching element 411, and the capacitor 421. Like the resin layer 127A, the resin layer 127B is a layer that forms part of the sealing resin 127 of FIG. 30 . The resin layer 127B is a layer that contains a thermosetting insulating resin material and an additive containing a metal element that constitutes part of the conductive portion 128. The resin layer 127B is formed, for example, by compression molding. These resin layers 127A and 127B form the sealing resin 127 that seals the switching element 411 and the capacitor 421. The support member 210 is then removed. The resin layer 127B may be made of the same material as the resin layer 127A.

[0341] As shown in FIG. 39 , the manufacturing method for the semiconductor light-emitting device 10 includes forming vias and surface electrodes in the resin layer 127B. More specifically, by irradiating the resin layer 127B with a laser, base layers for the first surface electrode 161A and the second surface electrode 162A and base layers for the first via 181 and the second via 182 are deposited. The base layers for the first via 181 and the second via 182 are deposited on the wall surfaces of the through-holes (via holes) formed by the laser irradiation. These base layers are composed of metal elements contained in an additive in the resin layer 127B. The metal elements are excited by the laser irradiation, and a metal layer containing the metal elements is deposited as the base layer. Next, a plating layer is formed to cover these base layers. This plating layer is formed from the material of the conductive portion 128 (e.g., a material containing Cu). The plating layer is formed, for example, by electroless plating. As a result, as shown in Fig. 39, first surface electrode 161A, second surface electrode 162A, first via 181, and second via 182 are formed by the base layer and the plating layer covering it. In the step shown in Fig. 39, other first surface electrodes 161B to 161D and other second surface electrodes 162B to 162D are formed through laser irradiation and electroless plating using techniques similar to those described above. Some or all of third via 183 may be formed in the step shown in Fig. 39.

[0342] Although not shown, in the method for manufacturing semiconductor light emitting device 10, semiconductor light emitting element 30A is mounted on first surface electrode 61A and second surface electrode 62A in the structure shown in Fig. 39 using a submount substrate 50. At this time, semiconductor light emitting elements 30B to 30D are also mounted on first surface electrodes 161B to 161D using submount substrate 50.

[0343] Furthermore, in the method for manufacturing semiconductor light emitting device 10, protection diode 70A is mounted on first surface electrode 61A and second surface electrode 62A. At this time, protection diodes 70B to 70D are also mounted on first surface electrodes 161B to 161D. Through the above steps, semiconductor light emitting device 10 is manufactured.

[0344] Effects of the Third Embodiment The semiconductor light emitting device 10 of the third embodiment has the following effects: (3-1) The switching elements 411 to 414 of the drive circuits 40A to 40D are each embedded in the sealing resin 127. Vertical transistors are used for the switching elements 411 to 414.

[0345] According to this configuration, electrical connection between the first electrode layer 130A and the second electrode layer 130B and the drain electrodes 41D and source electrodes 41S of the switching elements 411 to 414 can be achieved by vias (connection conductors) arranged in the sealing resin 127. Therefore, the electrical connection structure between the first electrode layer 130A and the second electrode layer 130B and the drain electrodes 41D and source electrodes 41S of the switching elements 411 to 414 can be simplified.

[0346] 40 and 41, a semiconductor light emitting device 10 according to a fourth embodiment will be described. The semiconductor light emitting device 10 according to the fourth embodiment differs from the semiconductor light emitting device 10 according to the third embodiment in that a single-channel driving type is adopted instead of a multi-channel driving type. In the following, components common to the third embodiment are designated by the same reference numerals, and their description will be omitted.

[0347] Fig. 40 schematically shows the planar structure of the semiconductor light-emitting device 10 of the fourth embodiment. Fig. 41 schematically shows the back surface structure of the semiconductor light-emitting device 10 of the fourth embodiment. In Fig. 40, openings in the main surface resist layer 129A are indicated by two-dot chain lines, and in Fig. 41, openings in the back surface resist layer 129B are indicated by two-dot chain lines. Note that Fig. 41 is shown as a perspective view to easily understand the correspondence between the first electrode layer 130A in Fig. 40 and the second electrode layer 130B in Fig. 41.

[0348] [Overall Configuration of Semiconductor Light-Emitting Device] As shown in Figure 40, the semiconductor light-emitting device 10 of the fourth embodiment includes a substrate 120, a semiconductor light-emitting element 30A, a drive circuit 40A, and a protection diode 70A. As in the third embodiment, the drive circuit 40A includes a switching element 411 and a capacitor 421, each embedded in a sealing resin 127. A vertical MOSFET is used for the switching element 411, and a silicon capacitor is used for the capacitor 421. The substrate 120 has a rectangular shape that is elongated in one direction (the X-axis direction in Figure 40) in a plan view.

[0349] [Electrode Layer of Conductive Portion] The substrate 120 of the fourth embodiment is a two-layer substrate, similar to that of the third embodiment. As shown in Figures 40 and 41 , the conductive portion 128 includes a first electrode layer 130A provided as a front electrode layer and a second electrode layer 130B provided as a back electrode layer.

[0350] 40 , the first electrode layer 130A includes a first surface electrode 161 and a second surface electrode 162 that are spaced apart from each other. Here, the first surface electrode 161 is an example of a "surface-side anode electrode," and the second surface electrode 162 is an example of a "surface-side cathode electrode."

[0351] 40 , the first surface electrode 161 and the second surface electrode 162 have the same shape. Each of the first surface electrode 161 and the second surface electrode 162 is elongated with its long side in the X-axis direction. The first surface electrode 161 and the second surface electrode 162 are arranged adjacent to each other in the direction of their short sides (the Y-axis direction in FIG. 40 ). The first surface electrode 161 and the second surface electrode 162 are used to mount the semiconductor light emitting element 30A and the protection diode 70A.

[0352] The semiconductor light emitting element 30A is mounted on a first surface electrode 161 and a second surface electrode 162 using a submount substrate 50. The submount substrate 50 is disposed so as to straddle the first surface electrode 161 and the second surface electrode 162. Although not shown, a second anode electrode 52B (see FIG. 30 ) of the submount substrate 50 is bonded to the first surface electrode 161 with a conductive bonding material SD, and a second cathode electrode 53B (see FIG. 30 ) of the submount substrate 50 is bonded to the second surface electrode 162 with a conductive bonding material SD. As a result, the anode electrode 34 of the semiconductor light emitting element 30A is electrically connected to the first surface electrode 161, and the cathode electrode 35 of the semiconductor light emitting element 30A is electrically connected to the second surface electrode 162.

[0353] The protection diode 70A is mounted across both the first surface electrode 161 and the second surface electrode 162. The anode electrode 71 of the protection diode 70A is joined to the second surface electrode 162 with a conductive bonding material, and the cathode electrode 72 of the protection diode 70A is joined to the first surface electrode 161 with a conductive bonding material. Therefore, the protection diode 70A is connected in anti-parallel to the semiconductor light emitting element 30A.

[0354] 41 , the second electrode layer 130B includes a first back surface electrode 171, a second back surface electrode 172, and third back surface electrodes 173A and 173B that are spaced apart from each other. These back surface electrodes 171, 172, 173A, and 173B function as external electrode terminals that are electrically connected to a circuit board (not shown) when the semiconductor light emitting device 10 is mounted on the circuit board.

[0355] The first back surface electrode 171 is provided so as to overlap the first surface electrode 161 and the second surface electrode 162 in a plan view. The first back surface electrode 171 has, for example, a rectangular shape that is elongated in the Y-axis direction. The first back surface electrode 171 is provided for electrical connection with the source electrode 41S of the switching element 411 and the second electrode 42B of the capacitor 421 embedded in the sealing resin 127. The first back surface electrode 171 includes an opening at a position that overlaps with the gate electrode 41G of the switching element 411 in a plan view. The first back surface electrode 171 functions as a ground terminal that supplies a ground voltage.

[0356] The second back surface electrode 172 is provided so as to overlap with the gate electrode 41G of the switching element 411 in a plan view. The second back surface electrode 172 is provided for electrical connection with the gate electrode 41G of the switching element 411. The second back surface electrode 172 is disposed within the opening of the first back surface electrode 171. The second back surface electrode 172 functions as a signal terminal that supplies a gate voltage signal.

[0357] The third back surface electrodes 173A and 173B are provided so as to overlap both the first surface electrode 161 and the second surface electrode 162 in a plan view. However, the third back surface electrodes 173A and 173B do not necessarily have to overlap the second surface electrode 162 in a plan view. The third back surface electrodes 173A and 173B are distributed and disposed on both sides of the first back surface electrode 171 in the X-axis direction. The third back surface electrodes 173A and 173B are provided for electrical connection with the first surface electrode 161. The third back surface electrodes 173A and 173B function as power supply terminals that supply a power supply voltage.

[0358] [Connection Structure Between Semiconductor Light Emitting Element and Drive Circuit] The conductive portion 128 includes a plurality of vias (connection conductors) that electrically connect the semiconductor light emitting element 30A, the switching element 411 and the capacitor 421 of the drive circuit 40A, the first electrode layer 130A, and the second electrode layer 130B. In the fourth embodiment, the conductive portion 128 includes first to sixth vias 181 to 186.

[0359] As shown in FIG. 40 , the first via 181 is disposed in the sealing resin 127 at a position overlapping the semiconductor light emitting element 30A, the first surface electrode 161, and the first electrode 42A of the capacitor 421 (see FIG. 31 ) in a plan view. The first via 181 penetrates the sealing resin 127 from the first surface electrode 161 to the first electrode 42A of the capacitor 421, thereby connecting the first surface electrode 161 and the first electrode 42A of the capacitor 421. Therefore, the anode electrode 34 of the semiconductor light emitting element 30A (see FIG. 31 ) is electrically connected to the first electrode 42A of the capacitor 421. The number of first vias 181 is not particularly limited and may be one or more. In the example of FIG. 40 , the first vias 181 are disposed in a matrix (2 × 2).

[0360] The second via 182 is disposed in the sealing resin 127 at a position overlapping the second surface electrode 162 and the drain electrode 41D (see FIG. 30 ) of the switching element 411 in a plan view. The second via 182 penetrates the sealing resin 127 from the second surface electrode 162 to the drain electrode 41D of the switching element 411, thereby connecting the second surface electrode 162 and the drain electrode 41D of the switching element 411.

[0361] The third via 183 is disposed in the sealing resin 127 at a position overlapping the first surface electrode 161 and the third back surface electrodes 173A and 173B in a plan view. The third via 183 penetrates the sealing resin 127 from the first surface electrode 161 to the third back surface electrodes 173A and 173B, thereby connecting the first surface electrode 161 to the third back surface electrodes 173A and 173B. The third back surface electrodes 173A and 173B are provided as power supply terminals, and the first surface electrode 161 is electrically connected to the first electrode 42A of the capacitor 421. As a result, when the switching element 411 is in the off state during operation of the semiconductor light emitting device 10, charge based on the power supply voltage is accumulated in the capacitor 421. The number of third vias 183 is not particularly limited and may be one or more. In the example shown in Figure 40, the third vias 183 are arranged in a matrix (e.g., 4 x 4) on the third back surface electrode 173A, and are also arranged in a matrix (e.g., 4 x 4) on the third back surface electrode 173B.

[0362] As shown in FIG. 41 , the fourth via 184 is disposed within the sealing resin 127 at a position overlapping the second electrode 42B (see FIG. 31 ) and the first back surface electrode 171 of the capacitor 421 in a plan view. The fourth via 184 penetrates the sealing resin 127 from the second electrode 42B of the capacitor 421 to the first back surface electrode 171, thereby connecting the second electrode 42B of the capacitor 421 to the first back surface electrode 171. The first back surface electrode 171 is provided as a ground terminal. Therefore, the second electrode 42B of the capacitor 421 is connected to ground. The number of fourth vias 184 is particularly limited to z, and may be one or more. In the example of FIG. 41 , the fourth vias 184 are disposed in a matrix (e.g., 2 × 2).

[0363] The fifth via 185 is disposed in the sealing resin 127 at a position overlapping both the source electrode 41S of the switching element 411 and the first back surface electrode 171 in a plan view. The fifth via 185 penetrates the sealing resin 127 from the source electrode 41S of the switching element 411 to the first back surface electrode 171, thereby connecting the source electrode 41S of the switching element 411 to the first back surface electrode 171. Therefore, the source electrode 41S of the switching element 411 is connected to ground.

[0364] The number of the fifth vias 185 is not particularly limited and may be 1 or more. In the fourth embodiment, for example, a plurality of (e.g., six) fifth vias 185 are arranged in a region where the source electrode 41S of the switching element 411 and the first back surface electrode 171 overlap.

[0365] The sixth via 186 is disposed in the sealing resin 127 at a position overlapping the second back surface electrode 172 and the gate electrode 41G of the switching element 411 in a plan view. The sixth via 186 penetrates the sealing resin 127 from the gate electrode 41G of the switching element 411 to the second back surface electrode 172, thereby connecting the gate electrode 41G of the switching element 411 to the second back surface electrode 172. When the semiconductor light emitting device 10 is in operation, a gate voltage signal is applied to the second back surface electrode 172, thereby supplying the gate electrode 41G of the switching element 411. The number of sixth vias 186 is not particularly limited and may be one or more.

[0366] [Current Path of Semiconductor Light-Emitting Device] In the fourth embodiment, the current path between the drive circuit 40A and the semiconductor light-emitting element 30A is configured in a loop shape, with current flowing sequentially through the first electrode 42A of the capacitor 421, the first via 181, the first surface electrode 161 of the first electrode layer 130A, the substrate-side anode electrode 52 of the submount substrate 50, the anode electrode 34 of the semiconductor light-emitting element 30A, the cathode electrode 35 of the semiconductor light-emitting element 30A, the substrate-side cathode electrode 53 of the submount substrate 50, the second surface electrode 162 of the first electrode layer 130A, the second via 182, the drain electrode 41D of the switching element 411, the source electrode 41S of the switching element 411, the fifth via 185, the first back surface electrode 171 of the second electrode layer 130B, the fourth via 184, and the second electrode 42B of the capacitor 421.

[0367] Effects of the Fourth Embodiment The semiconductor light-emitting device 10 of the fourth embodiment has the following effects. (4-1) The second electrode layer 130B includes a first back surface electrode 171, a second back surface electrode 172, and third back surface electrodes 173A and 173B. Each of the third back surface electrodes 173A and 173B has a larger area than the first back surface electrode 171 and the second back surface electrode 172 in a plan view. With this configuration, the heat dissipation area provided by the third back surface electrodes 173A and 173B can be increased, and therefore heat generated in the semiconductor light-emitting device 10 can be efficiently dissipated.

[0368] <Modifications> The above-described embodiments can be modified as follows: Furthermore, the above-described embodiments and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0369] In the first embodiment, the shapes of the first cathode electrode 53A and the second cathode electrode 53B of the submount substrate 50 in a planar view can be arbitrarily changed. For example, the first cathode electrode 53A may be annular with a gap in a planar view. That is, the first cathode electrode 53A may be provided so as to partially surround the first anode electrode 52A in a planar view. For example, the second cathode electrode 53B may be annular with a gap in a planar view. That is, the second cathode electrode 53B may be provided so as to partially surround the second anode electrode 52B in a planar view. Furthermore, the thickness of the submount substrate 50 can be arbitrarily changed. For example, the thickness of the submount substrate 50 may be thinner than the thickness of the semiconductor light emitting elements 30A-30H.

[0370] In the first embodiment, the submount substrate 50 may be omitted. In this case, the anode electrodes 34 of the semiconductor light emitting elements 30A to 30H are mounted on the second surface electrodes 62A to 62H, respectively, and the cathode electrodes 35 of the semiconductor light emitting elements 30A to 30H are mounted on the central electrode patterns PA of the first surface electrodes 61A to 61H.

[0371] The first and second embodiments may be changed to a single-channel drive configuration in which one semiconductor light emitting element, one drive circuit, and one protection diode are provided, as in the fourth embodiment.

[0372] In the first embodiment, it is possible to arbitrarily change the material constituting the substrate 20. In one example, the first to third base materials 27A to 27C of the substrate 20 may be made of a sealing resin containing a thermosetting insulating resin material and an additive, as in the second embodiment.

[0373] In the second and third embodiments, it is possible to arbitrarily change the material constituting the substrate 120. In one example, the substrate 120 may include at least one of glass epoxy resin, ceramic, and silicon.

[0374] In the second and third embodiments, as in the first embodiment, the semiconductor light emitting device 10 may include eight semiconductor light emitting elements 30A to 30H, eight drive circuits 40A to 40H, and eight protection diodes 70A to 70H.

[0375] In the first embodiment, vertical MOSFETs may be used for the switching elements 411 to 418 of the drive circuits 40A to 40H. In the first embodiment, the number of capacitors 421 to 428 of the drive circuits 40A to 40H may be changed as desired. In one example, the number of capacitors 421 to 428 of the drive circuits 40A to 40H may be one.

[0376] In each embodiment, the configuration of the semiconductor light emitting elements 30A to 30H (30A to 30D) can be modified as desired. In one example, the semiconductor light emitting elements 30A to 30H may be modified as shown in Fig. 42. Fig. 42 schematically shows the cross-sectional structure of a modified semiconductor light emitting element 30A.

[0377] 42 , the cathode electrode 35 of the semiconductor light emitting element 30A may be provided on a first surface 36A of a semiconductor substrate 36. The cathode electrode 35 is in contact with the first surface 36A, for example. The cathode electrode 35 may be provided so as to surround the semiconductor layer 37 in a plan view. In one example, the cathode electrode 35 is disposed at a distance from the semiconductor layer 37.

[0378] The semiconductor layer 37 surrounded by the cathode electrode 35 has a rectangular flat plate shape with its thickness oriented in the Z-axis direction. As in the previous embodiments, the semiconductor layer 37 includes an active layer 37A, a photonic crystal layer 37B, a first cladding layer 37C, a second cladding layer 37D, and a contact layer 37E. This semiconductor light emitting element 30A can also be mounted on the submount substrate 50 or the first electrode layer 28A (130A) without using wires.

[0379] In each embodiment, the configuration of the cathode electrode 35 of the semiconductor light emitting element 30A can be changed as desired. In one example, the contact portion 35C may be omitted from the cathode electrode 35. In this case, the cathode electrode 35 is in contact with the semiconductor substrate 36. Note that the same changes can be made to the semiconductor light emitting elements 30B to 30H (30B to 30D).

[0380] In each embodiment, a second insulating layer 39B may be interposed between the cathode electrode 35 and the semiconductor substrate 36. In this case, the cathode electrode 35 is in contact with the side surface 37PB of the mesa portion 37P via the contact portion 35C.

[0381] In each embodiment, PCSEL elements are used as the semiconductor light emitting elements 30A to 30H (30A to 30D), but they are not limited to PCSEL elements. For example, vertical cavity surface emitting laser (VCSEL) elements may be used as light emitting elements that emit light in a direction intersecting the mounting surface.

[0382] In each embodiment, the drive circuits 40A to 40H (40A to 40D) are arranged in a rotationally symmetric relationship in the peripheral area AP of the first to fourth partition areas SP1 to SP4, but they may be arranged in any layout in the peripheral area AP.

[0383] In each embodiment, the gate drivers 305A to 305H (305A to 305D) may be mounted on the substrate 20 (120). That is, the semiconductor light emitting device 10 may include the gate drivers 305A to 305H (305A to 305D).

[0384] In each embodiment, backflow prevention diodes 304A to 304H (304A to 304D) may be mounted on the substrate 20 (120). That is, the semiconductor light emitting device 10 may include the backflow prevention diodes 304A to 304H (304A to 304H) provided between the power supply input section formed by the DC power supply 301, the capacitor 302, and the current limiting resistor 303 and the drive circuits 40A to 40H (40A to 40D).

[0385] In the first embodiment, the protection diodes 70A to 70H may not be mounted on the substrate 20 (120). That is, the semiconductor light emitting device 10 may not include the protection diodes 70A to 70H. In addition, as an example, in the second and third embodiments, the protection diodes 70A to 70D may be embedded in the sealing resin 127. In addition, as an example, in the second and third embodiments, the semiconductor light emitting device 10 may not include the protection diodes 70A to 70D. In addition, as an example, in the fourth embodiment, the protection diode 70A may be embedded in the sealing resin 127. In addition, as an example, in the fourth embodiment, the semiconductor light emitting device 10 may not include the protection diode 70A.

[0386] In the first embodiment, among the switching elements 411 to 418 and capacitors 421 to 428 of the drive circuits 40A to 40H, the capacitors 421 to 428 may be provided external to the semiconductor light-emitting device 10. That is, the drive circuits 40A to 40H of the semiconductor light-emitting device 10 may include the switching elements 411 to 418 but not the capacitors 421 to 428. Also, among the switching elements 411 to 418 and capacitors 421 to 428 of the drive circuits 40A to 40H, the switching elements 411 to 418 may be provided external to the semiconductor light-emitting device 10. That is, the drive circuits 40A to 40H of the semiconductor light-emitting device 10 may include the capacitors 421 to 428 but not the switching elements 411 to 418. Note that similar modifications may be made to the second to fourth embodiments.

[0387] In each embodiment, the material constituting the substrate 20 (120) can be changed as desired. One or more of the various examples described in this disclosure can be combined to the extent that they are not technically inconsistent.

[0388] The term "on" as used in this disclosure includes the meanings of "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.

[0389] The Z-axis direction used in this disclosure does not necessarily have to be the vertical direction, nor does it have to completely coincide with the vertical direction. Therefore, the various structures according to this disclosure are not limited to the "up" and "down" in the Z-axis direction described in this disclosure being "up" and "down" in the vertical direction. For example, the X-axis direction may be the vertical direction, or the Y-axis direction may be the vertical direction.

[0390] <Supplementary Notes> The technical ideas that can be understood from this disclosure are described below. Note that, for the purpose of aiding understanding and not intending to be limiting, the components described in the supplementary notes are given the reference numerals of the corresponding components in the above embodiment. The reference numerals are shown as examples to aid understanding, and the components described in each supplementary note should not be limited to the components indicated by the reference numerals.

[0391] [Supplementary Note 1] A substrate (20) including a first substrate surface (21) and a second substrate surface (22) opposite to the first substrate surface (21), at least one semiconductor light-emitting element (30A-30H) mounted on the first substrate surface (21), and at least one drive circuit (40A-40H) provided on the substrate (20) for driving the at least one semiconductor light-emitting element (30A-30H), wherein the substrate (20) includes: a front-side anode electrode (62A-62H) and a front-side cathode electrode (61A-61H) provided on the first substrate surface (21), and a back electrode layer (28B) provided on the second substrate surface (22), wherein the at least one semiconductor light-emitting element (30A-30H) includes: a first element surface (31) including a light-emitting region (33) that emits light, a semiconductor substrate (36) including: an anode electrode (34) provided on the opposite side of the first element surface (31) and electrically connected to the front-side anode electrodes (62A to 62H); a cathode electrode (35) provided on the opposite side of the first element surface (31) and electrically connected to the front-side cathode electrodes (61A to 61H); a semiconductor substrate (36) including a first surface (36A) and a second surface (36B) opposite the first surface (36A) and constituting the first element surface (31); and a semiconductor layer (37) provided on the first surface (36A) and configured to generate light, the semiconductor light-emitting device (10) being mounted on the substrate (20) such that the semiconductor layer (37) is disposed between the semiconductor substrate (36) and the substrate (20) in a thickness direction (Z) of the substrate (20).

[0392] [Supplementary Note 2] The semiconductor light-emitting device according to Supplementary Note 1, wherein the cathode electrode (35) is provided so as to surround the anode electrode (34) when viewed in the thickness direction (Z) of the substrate (20).

[0393] [Supplementary Note 3] The semiconductor light-emitting device according to Supplementary Note 2, wherein the semiconductor layer (37) includes a groove (38) surrounding the anode electrode (34) when viewed from the thickness direction (Z) of the substrate (20) and providing a groove (38) that exposes the semiconductor substrate (36), and a portion of the cathode electrode (35) extends into the groove (38).

[0394] [Supplementary Note 4] The semiconductor layer (37) includes a mesa portion (37P) surrounded by the groove (38), and an outer peripheral portion (37Q) provided outward from the groove (38), and the at least one semiconductor light emitting element (30A to 30H) includes a first insulating layer (39A) provided between the mesa portion (37P) and the anode electrode (34), and a second insulating layer (39B) provided between the outer peripheral portion (37Q) and the cathode electrode (35), the second insulating layer (39B) covering an inner surface (37QB) of the outer peripheral portion (37Q) that constitutes the groove (38), and the anode electrode (34) includes a portion (34A) that penetrates the first insulating layer (39A) and contacts the mesa portion (37P), The semiconductor light-emitting device according to claim 3, wherein the cathode electrode (35) extends into the groove (38) and includes a portion (35B, 35C) that contacts at least one of a side surface (37PB) of the mesa portion (37P) and the semiconductor substrate (36).

[0395] [Appendix 5] The semiconductor light-emitting device according to appendix 1 or 2, wherein the cathode electrode (35) is provided on the first surface (36A) and includes a portion that is provided so as to surround the semiconductor layer (37) when viewed from the thickness direction (Z) of the substrate (20).

[0396] [Supplementary Note 6] The semiconductor light-emitting device according to any one of Supplementary Notes 1 to 5, comprising a submount substrate (50) provided on the first substrate surface (21) and having the semiconductor light-emitting element (30A-30H) mounted thereon, wherein the submount substrate (50) comprises an insulating base material (51), a substrate-side anode electrode (52) electrically connected to the anode electrode (34), and a substrate-side cathode electrode (53) electrically connected to the cathode electrode (35), and both the substrate-side anode electrode (52) and the substrate-side cathode electrode (53) penetrate the base material (51).

[0397] [Supplementary Note 7] The substrate (51) includes a first substrate surface (51A) on the semiconductor light emitting element (30A-30H) side and a second substrate surface (51B) opposite to the first substrate surface (51A), the substrate-side anode electrode (52) includes: a first anode electrode (52A) provided on the first substrate surface (51A); and a second anode electrode (52B) provided on the second substrate surface (51B), and a first via (52C) ​​provided in the substrate (51) and connecting the first anode electrode (52A) and the second anode electrode (52B), the substrate-side cathode electrode (53) includes: a first cathode electrode (53A) provided on the first substrate surface (51A); and a second cathode electrode (53B) provided on the second substrate surface (51B), and a second via (53C) provided within the base material (51) and connecting the first cathode electrode (53A) and the second cathode electrode (53B), wherein the first cathode electrode (53A) is provided so as to surround the first anode electrode (52A) when viewed from the thickness direction (Z) of the substrate (20), and the second cathode electrode (53B) is arranged side by side with the second anode electrode (52B) in a first direction (Y) when viewed from the thickness direction (Z) of the substrate (20).

[0398] [Appendix 8] The semiconductor light-emitting device according to appendix 6 or 7, wherein the submount substrate (50) is arranged so as to straddle the front-side anode electrodes (131A to 131D) and the front-side cathode electrodes (132A to 132D), the substrate-side anode electrode (52) and the front-side anode electrodes (131A to 131D) are arranged opposite to each other, and the substrate-side anode electrode (52) is electrically connected to the front-side anode electrodes (131A to 131D), and the substrate-side cathode electrode (53) and the front-side cathode electrodes (132A to 132D) are arranged opposite to each other, and the substrate-side cathode electrode (53) is electrically connected to the front-side cathode electrodes (132A to 132D).

[0399] [Supplementary Note 9] The semiconductor light emitting device according to any one of Supplementary Notes 1 to 8, wherein at least a part of the drive circuit (40A to 40D) is embedded in the substrate (120).

[0400] [Supplementary Note 10] The semiconductor light emitting device according to any one of Supplementary Notes 1 to 9, wherein a plurality of the semiconductor light emitting elements (30A to 30H) are provided, a plurality of the drive circuits (40A to 40H) are provided according to the number of the plurality of semiconductor light emitting elements (30A to 30H), and each of the plurality of drive circuits (40A to 40H) includes a switching element (411 to 418) and a capacitor (421 to 428).

[0401] [Appendix 11] The semiconductor light emitting device according to any one of appendices 1 to 10, wherein the substrate (20 / 120) contains at least one of glass epoxy resin, ceramic, and silicon.

[0402] [Supplementary Note 12] The substrate (20) comprises: a surface electrode layer (28A) provided on the first substrate surface (21) and including the surface-side anode electrodes (62A-62H) and the surface-side cathode electrodes (61A-61H); intermediate electrode layers (28C, 28D) provided within the substrate (20) in a thickness direction (Z) of the substrate (20); and a plurality of vias (111A-111H, 112A-112H, 113A-113H, 114A-114D, 115A-115H) provided within the substrate (20) and electrically connecting the surface electrode layer (28A), the back electrode layer (28B), and the intermediate electrode layer (28C, 28D), A current path (CP) of a current flowing through the drive circuit (40A to 40H) and the semiconductor light-emitting element (30A to 30H) is formed by the surface electrode layer (28A), the intermediate electrode layer (28C), and some of the plurality of vias (111A to 111H, 112A to 112H, 113A to 113H, 114A to 114D, 115A to 115H).

[0403] [Supplementary Note 13] The semiconductor light emitting device according to any one of Supplementary Notes 1 to 12, further comprising: a diode (304A to 304H) provided between a power supply input unit (301, 302, 303) that supplies current to the semiconductor light emitting element (30A to 30H) and the drive circuit (40A to 40D) and the drive circuit (40A to 40D).

[0404] [Supplementary Note 14] The semiconductor light emitting device according to Supplementary Note 10, further comprising gate drivers (305A to 305H) that drive the switching elements (411 to 418).

[0405] [Supplementary Note 15] The semiconductor light emitting device according to Supplementary Note 10, wherein the driving circuit (40A to 40H) includes a plurality of the capacitors (421 to 428).

[0406] [Appendix 16] The semiconductor light-emitting device according to appendix 10, wherein the switching elements (411 to 418) are MOSFETs or nitride semiconductor transistors.

[0407] [Supplementary Note 17] The semiconductor light-emitting device according to Supplementary Note 10, wherein the capacitors (421 to 428) are ceramic capacitors or silicon capacitors.

[0408] [Appendix 18] The semiconductor light-emitting device according to appendix 10, wherein the switching elements (411 to 414) are vertical MOSFETs, and the capacitors (421 to 424) are silicon capacitors.

[0409] [Supplementary Note 19] The semiconductor light emitting device according to any one of Supplementary Notes 1 to 18, wherein the semiconductor light emitting element (30A to 30H) is a surface emitting laser element.

[0410] [Supplementary Note 20] The semiconductor light emitting device according to any one of Supplementary Notes 1 to 19, wherein the semiconductor light emitting element (30A to 30H) is a photonic crystal surface emitting laser element or a vertical cavity surface emitting laser element.

[0411] [Appendix 21] The semiconductor light-emitting device according to Appendix 7, wherein the substrate-side cathode electrode (53) is arranged to surround the substrate-side anode electrode (52) when viewed from the thickness direction (Z) of the submount substrate (50).

[0412] [Appendix 22] The semiconductor light-emitting device according to Appendix 21, wherein the front-side cathode electrodes (61A to 61H) are arranged to surround the front-side anode electrodes (62A to 62H) when viewed from the thickness direction (Z) of the substrate (20).

[0413] [Appendix 23] The semiconductor light-emitting device according to appendix 6 or 7, wherein the anode electrode (34) and the substrate-side anode electrode (52) are bonded to the cathode electrode (35) and the substrate-side cathode electrode (53), respectively, by a conductive bonding material (SD).

[0414] [Appendix 24] The semiconductor light-emitting device according to Appendix 8, wherein the substrate-side anode electrode (52) and the surface-side anode electrode (62A to 62H) are bonded to the substrate-side cathode electrode (53) and the surface-side cathode electrode (61A to 61H) by a conductive bonding material (SD).

[0415] [Supplementary Note 25] A substrate (20) including a first substrate surface (21) and a second substrate surface (22) opposite to the first substrate surface (21), at least one semiconductor light-emitting element (30A-30H) mounted on the first substrate surface (21), and at least one drive circuit (40A-40H) provided on the substrate (20) for driving the at least one semiconductor light-emitting element (30A-30H), wherein the substrate (20) includes: a front-side anode electrode (62A-62H) and a front-side cathode electrode (61A-61H) provided on the first substrate surface (21), and a back electrode layer (28B) provided on the second substrate surface (22), wherein the at least one semiconductor light-emitting element (30A-30H) includes: a first element surface (31) including a light-emitting region (33) that emits light, The semiconductor light-emitting device (10) includes: an anode electrode (34) provided on the opposite side of the first element surface (31) and electrically connected to the front-side anode electrodes (62A to 62H); and a cathode electrode (35) provided on the opposite side of the first element surface (31) and electrically connected to the front-side cathode electrodes (61A to 61H), wherein the cathode electrode (35) is provided so as to surround the anode electrode (34) when viewed from the thickness direction (Z) of the substrate (20).

[0416] [Supplementary Note 26] A substrate (20) including a first substrate surface (21) and a second substrate surface (22) opposite to the first substrate surface (21), at least one semiconductor light-emitting element (30A-30H) mounted on the first substrate surface (21), at least one drive circuit (40A-40H) provided on the substrate (20) for driving the at least one semiconductor light-emitting element (30A-30H), and a submount substrate (50) provided on the first substrate surface (21) and on which the semiconductor light-emitting element (30A-30H) is mounted, wherein the substrate (20) includes: front-side anode electrodes (62A-62H) and front-side cathode electrodes (61A-61H) provided on the first substrate surface (21), and a back electrode layer (28B) provided on the second substrate surface (22), The at least one semiconductor light emitting element (30A to 30H) includes: a first element surface (31) including a light emitting region (33) that emits light; an anode electrode (34) provided on the opposite side of the first element surface (31) and electrically connected to the front-side anode electrode (62A to 62H); and a cathode electrode (35) provided on the opposite side of the first element surface (31) and electrically connected to the front-side cathode electrode (61A to 61H).

[0417] [Appendix 27] The semiconductor light-emitting device according to Appendix 26, wherein the submount substrate (50) includes an insulating base material (51), a substrate-side anode electrode (52) electrically connected to the anode electrode (34), and a substrate-side cathode electrode (53) electrically connected to the cathode electrode (35), and both the substrate-side anode electrode (52) and the substrate-side cathode electrode (53) penetrate the base material (51).

[0418] [Appendix 28] The semiconductor light-emitting device according to Appendix 27, wherein the substrate-side cathode electrode (53) is arranged to surround the substrate-side anode electrode (52) when viewed from the thickness direction (Z) of the submount substrate (50).

[0419] [Appendix 29] The semiconductor light-emitting device according to appendix 28, wherein the front-side cathode electrodes (61A to 61H) are arranged to surround the front-side anode electrodes (62A to 62H) when viewed from the thickness direction (Z) of the substrate (20).

[0420] [Appendix 30] The semiconductor light-emitting device according to any one of Appendices 27 to 29, wherein the anode electrode (34) and the substrate-side anode electrode (52) are bonded to the cathode electrode (35) and the substrate-side cathode electrode (53) by a conductive bonding material (SD).

[0421] [Appendix 31] The semiconductor light-emitting device according to appendix 30, wherein the substrate-side anode electrode (52) and the surface-side anode electrode (62A to 62H) are bonded to the substrate-side cathode electrode (53) and the surface-side cathode electrode (61A to 61H) by a conductive bonding material (SD).

[0422] [Supplementary Note 32] The substrate (51) includes a first substrate surface (51A) on the semiconductor light emitting element (30A-30H) side and a second substrate surface (51B) opposite to the first substrate surface (51A), the substrate-side anode electrode (52) includes: a first anode electrode (52A) provided on the first substrate surface (51A), and a second anode electrode (52B) provided on the second substrate surface (51B), and a first via (52C) ​​provided in the substrate (51) and connecting the first anode electrode (52A) and the second anode electrode (52B), the substrate-side cathode electrode (53) includes: a first cathode electrode (53A) provided on the first substrate surface (51A), and a second cathode electrode (53B) provided on the second substrate surface (51B), a second via (53C) provided within the base material (51) and connecting the first cathode electrode (53A) and the second cathode electrode (53B), wherein the first cathode electrode (53A) is provided so as to surround the first anode electrode (52A) when viewed from the thickness direction (Z) of the substrate (20), and the second cathode electrode (53B) is arranged alongside the second anode electrode (52B) in a first direction (Y) when viewed from the thickness direction (Z) of the substrate (20).

[0423] [Appendix 33] The semiconductor light-emitting device according to Appendix 32, wherein the cathode electrode (35) is arranged to surround the anode electrode (34) when viewed from the thickness direction (Z) of the substrate (20), and the anode electrode (34) and the first anode electrode (52A) are bonded to the cathode electrode (35) and the first cathode electrode (53A), respectively, by a conductive bonding material (SD).

[0424] [Appendix 34] The semiconductor light-emitting device according to appendix 32 or 33, wherein the front-side anode electrode (131A) and the front-side cathode electrode (132A) are arranged to be spaced apart in the first direction (Y), the submount substrate (50) is arranged to straddle the front-side anode electrode (131A) and the front-side cathode electrode (132A) in the first direction (Y), the substrate-side anode electrode (52) and the front-side anode electrode (131A) are arranged opposite each other, and the substrate-side anode electrode (52) is electrically connected to the front-side anode electrode (131A), and the substrate-side cathode electrode (53) and the front-side cathode electrode (132A) are arranged opposite each other, and the substrate-side cathode electrode (53) is electrically connected to the front-side cathode electrode (132A).

[0425] [Appendix 35] The semiconductor light-emitting device according to Appendix 34, wherein the substrate-side anode electrode (52) and the surface-side anode electrode (131A) are bonded to the substrate-side cathode electrode (53) and the surface-side cathode electrode (132A), respectively, by a conductive bonding material (SD).

[0426] [Appendix 36] The semiconductor light-emitting device according to any one of Appendices 1 to 9, wherein a plurality of the semiconductor light-emitting elements (30A to 30H) are provided, the substrate (20) includes, when viewed from the thickness direction (Z) of the substrate (20), a central region (AC) including the center of the substrate (20) and a peripheral region (AP) surrounding the central region (AC), and the plurality of semiconductor light-emitting elements (30A to 30H) are collectively arranged in the central region (AC).

[0427] [Supplementary Note 37] The semiconductor light emitting device according to Supplementary Note 36, wherein the plurality of semiconductor light emitting elements (30A to 30H) are arranged adjacent to one another in a matrix in the central region (AC).

[0428] [Appendix 38] The semiconductor light-emitting device according to appendix 36 or 37, wherein a plurality of the driving circuits (40A to 40H) are provided in accordance with the number of the plurality of semiconductor light-emitting elements (30A to 30H), and the plurality of driving circuits (40A to 40H) are arranged in the peripheral region (AP).

[0429] The above description is merely illustrative. Those skilled in the art will recognize that many more possible combinations and permutations are possible other than the components and methods (manufacturing processes) listed for the purpose of illustrating the technology of the present disclosure. The present disclosure is intended to embrace all alternatives, modifications, and variations that fall within the scope of the present disclosure, including the claims.

[0430] DESCRIPTION OF SYMBOLS 10...Semiconductor light emitting device 20...Substrate 21...First substrate surface 22...Second substrate surface 23-26...First to fourth side surfaces 28A...First electrode layer (surface electrode layer) 28B...Second electrode layer (rear electrode layer) 29A...Main surface resist layer 29B...Rear surface resist layer 30A-30H...Semiconductor light emitting element 31...First element surface 32...Second element surface 33...Light emitting region 34...Anode electrode 34A...Contact portion 35...Cathode electrode 35A...First portion 35B...Second portion 35C...Contact portion 36...Semiconductor substrate 36A...First surface 36B...Second surface 37...Semiconductor layer 37A...Active layer 37B...Photonic crystal layer 37C...First cladding layer 37D...Second cladding layer 37E...Contact layer 37P...Mesa portion 37PA...Main surface 37PB...Side surface 37Q...Outer periphery 37QA...Main surface 37QB...Inner surface 38...Groove 39...Insulating layer 39A...First insulating layer 39B...Second insulating layer 40A to 40H...Drive circuits 411 to 418...Switching elements 41A...First element surface 41B...Second element surface 41S...Source electrode 41G...Gate electrode 41D...Drain electrode 421 to 428...Capacitors 42A...First electrode 42B...Second electrode 50...Submount substrate 51...Base material 51A...First base material surface 51B...Second base material surface 52...Substrate-side anode electrode 52A...First anode electrode 52B...Second anode electrode 52C...First via 53...Substrate-side cathode electrode 53A...First cathode electrode 53AA...Opening 53B...Second cathode electrode 53C...Second via 61A to 61H...First surface electrode 62A to 62H...Second surface electrode 63A to 63H...Third surface electrode 64...Fourth surface electrode 65A to 65H...Fifth surface electrode 66A to 66H...Sixth surface electrode 70A to 70D...Protection diode 71...Anode electrode 72...Cathode electrode 81A to 81H...First rear surface electrode 82A to 82H...Second rear surface electrode 83A to 83H...Third rear surface electrode 84A to 84D...Fourth rear surface electrode 85A to 85H...Fifth rear surface electrode 86A to 86H...Sixth rear surface electrode 91A to 91H...First intermediate electrode 92A to 92H...Second intermediate electrode 93A to 93H...Third intermediate electrode 94A to 94D...Fourth intermediate electrode95A to 95H...fifth intermediate electrode 101A to 101H...first intermediate electrode 102A to 102H...second intermediate electrode 103A to 103H...third intermediate electrode 104A to 104D...fourth intermediate electrode 105A to 105H...fifth intermediate electrode 111A to 111H...first via 112A to 112H...second via 113A to 113H...third via 114A to 114D...fourth via 115A to 115H...fifth via 120...substrate 121...first substrate surface 122...second substrate surface 123 to 126...first to fourth side surfaces 127...sealing resin 127A, 127B...resin layer 128...conductive portion 129A...main surface resist layer 129B...rear surface resist layer 130A...First electrode layer 130B...Second electrode layer 131A to 131D...First surface electrode 132A to 132D...Second surface electrode 133A to 133D...Third surface electrode 134A to 134D...Fourth surface electrode 141...First rear surface electrode 142A to 142D...Second rear surface electrode 143A to 143D...Third rear surface electrode 151 to 155...First to fifth vias 161, 161A to 161D...First surface electrode 162, 162A to 162D...Second surface electrode 171...First rear surface electrode 172A to 172D...Second rear surface electrode 173A to 173D...Third rear surface electrode 181 to 186...First to sixth vias 200, 210...Support member 300...Light-emitting system 301... DC power supply 302... Capacitor 303... Current limiting resistor 304A to 304H... Reverse current prevention diode 305A to 305H... Gate driver 306A to 306H... Pulse generator 307A to 307H... Control power supply CP... Current path PA... Central electrode pattern PB... Peripheral electrode pattern AC... Central region AP... Peripheral region SP1 to SP4... First to fourth divided regions VC, HC... Virtual center line

Claims

1. A semiconductor light-emitting device comprising: a substrate including a first substrate surface and a second substrate surface opposite to the first substrate surface; at least one semiconductor light-emitting element mounted on the first substrate surface; and at least one drive circuit provided on the substrate for driving the at least one semiconductor light-emitting element, wherein the substrate includes: a front-side anode electrode and a front-side cathode electrode provided on the first substrate surface; and a back electrode layer provided on the second substrate surface, wherein the at least one semiconductor light-emitting element comprises: a first element surface including a light-emitting region that emits light, an anode electrode provided on the opposite side to the first element surface and electrically connected to the front-side anode electrode, a cathode electrode provided on the opposite side to the first element surface and electrically connected to the front-side cathode electrode, a semiconductor substrate including a first surface and a second surface opposite to the first surface and constituting the first element surface, and a semiconductor layer provided on the first surface and configured to generate light, wherein the semiconductor layer is mounted on the substrate such that the semiconductor layer is disposed between the semiconductor substrate and the substrate in a thickness direction of the substrate. Semiconductor light-emitting device.

2. The semiconductor light emitting device according to claim 1, wherein the cathode electrode is provided so as to surround the anode electrode when viewed in the thickness direction of the substrate.

3. The semiconductor light-emitting device according to claim 2, wherein the semiconductor layer includes a groove surrounding the anode electrode when viewed in the thickness direction of the substrate and exposing the semiconductor substrate, and a portion of the cathode electrode extends into the groove.

4. The semiconductor light-emitting device according to claim 3, wherein the semiconductor layer includes a mesa portion surrounded by the groove and a peripheral portion provided outward from the groove, and the at least one semiconductor light-emitting element includes a first insulating layer provided between the mesa portion and the anode electrode and a second insulating layer provided between the peripheral portion and the cathode electrode, the second insulating layer covering the inner surface of the peripheral portion that constitutes the groove, the anode electrode including a portion that penetrates the first insulating layer and contacts the mesa portion, and the cathode electrode including a portion that extends into the groove and contacts a side surface of the mesa portion and at least one of the semiconductor substrate.

5. The semiconductor light emitting device according to claim 1 or 2, wherein the cathode electrode is provided on the first surface and includes a portion that surrounds the semiconductor layer when viewed in the thickness direction of the substrate.

6. A semiconductor light emitting device according to any one of claims 1 to 5, comprising a submount substrate provided on the surface of said first substrate and on which said semiconductor light emitting element is mounted, said submount substrate comprising: an insulating base material; a substrate-side anode electrode electrically connected to said anode electrode; and a substrate-side cathode electrode electrically connected to said cathode electrode, and both said substrate-side anode electrode and said substrate-side cathode electrode penetrate said base material.

7. The semiconductor light emitting device according to claim 6, wherein the substrate includes a first substrate surface on the semiconductor light emitting element side and a second substrate surface opposite to the first substrate surface, the substrate-side anode electrode includes: a first anode electrode provided on the first substrate surface; a second anode electrode provided on the second substrate surface; and a first via provided within the substrate and connecting the first anode electrode and the second anode electrode, the substrate-side cathode electrode includes: a first cathode electrode provided on the first substrate surface; a second cathode electrode provided on the second substrate surface; and a second via provided within the substrate and connecting the first cathode electrode and the second cathode electrode, the first cathode electrode is provided so as to surround the first anode electrode when viewed from the thickness direction of the substrate, and the second cathode electrode is arranged side by side with the second anode electrode in the first direction when viewed from the thickness direction of the substrate.

8. The semiconductor light-emitting device according to claim 6 or 7, wherein the submount substrate is arranged to straddle the front-side anode electrode and the front-side cathode electrode, the substrate-side anode electrode and the front-side anode electrode are arranged opposite each other and the substrate-side anode electrode is electrically connected to the front-side anode electrode, and the substrate-side cathode electrode and the front-side cathode electrode are arranged opposite each other and the substrate-side cathode electrode is electrically connected to the front-side cathode electrode.

9. The semiconductor light emitting device according to any one of claims 1 to 8, wherein at least a part of the drive circuit is embedded in the substrate.

10. A semiconductor light emitting device according to any one of claims 1 to 9, wherein a plurality of the semiconductor light emitting elements are provided, a plurality of the drive circuits are provided in accordance with the number of the semiconductor light emitting elements, and each of the plurality of drive circuits includes a switching element and a capacitor.

11. The semiconductor light emitting device according to any one of claims 1 to 10, wherein the substrate contains at least one of glass epoxy resin, ceramic, and silicon.

12. A semiconductor light-emitting device according to any one of claims 1 to 11, wherein the substrate comprises: a surface electrode layer provided on the first substrate surface and including the surface-side anode electrode and the surface-side cathode electrode; an intermediate electrode layer provided within the substrate in the thickness direction of the substrate; and a plurality of vias provided within the substrate and electrically connecting the surface electrode layer, the back electrode layer, and the intermediate electrode layer; and a current path for a current flowing between the drive circuit and the semiconductor light-emitting element is formed by the surface electrode layer, the intermediate electrode layer, and some of the plurality of vias.

13. The semiconductor light emitting device according to any one of claims 1 to 12, further comprising a diode provided between said drive circuit and a power supply input section that supplies current to said semiconductor light emitting element and said drive circuit.

14. The semiconductor light emitting device according to claim 10, further comprising a gate driver that drives the switching element.

15. The semiconductor light emitting device according to claim 10, wherein the drive circuit includes a plurality of capacitors.

16. The semiconductor light emitting device according to claim 10, wherein the switching element is a MOSFET or a nitride semiconductor transistor.

17. The semiconductor light emitting device according to claim 10, wherein the capacitor is a ceramic capacitor or a silicon capacitor.

18. The semiconductor light emitting device according to claim 10, wherein the switching element is a vertical MOSFET, and the capacitor is a silicon capacitor.

19. The semiconductor light emitting device according to any one of claims 1 to 18, wherein the semiconductor light emitting element is a surface emitting laser element.

20. The semiconductor light emitting device according to any one of claims 1 to 19, wherein the semiconductor light emitting element is a photonic crystal surface emitting laser element or a vertical cavity surface emitting laser element.

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