Semiconductor laser device and manufacturing method for semiconductor laser device

Abstract

A semiconductor laser device (10) comprises: a sub-mount (80) having a mounting surface (80a); a spacer (40) disposed on the mounting surface (80a); a semiconductor laser element (20) disposed above the spacer (40); and a junction member (60) that is disposed between the spacer (40) and the semiconductor laser element (20) and joins the spacer (40) and the semiconductor laser element (20). The semiconductor laser element (20) has a counter surface (20a) that faces the sub-mount (80). In a plan view of the mounting surface (80a), the spacer (40) is not present on the outer side of one end of the semiconductor laser element (20) in a first direction perpendicular to the resonance direction of the laser beam (L0), and the junction member (60) is disposed between one end of the semiconductor laser element (20) and one end of the spacer (40) in the first direction, and the counter surface (20a) is exposed from the junction member (60) at one end of the semiconductor laser element (20).

Description

Semiconductor laser device and method for manufacturing semiconductor laser device

[0001] The present disclosure relates to a semiconductor laser device and a method for manufacturing a semiconductor laser device.

[0002] Semiconductor laser devices are known that include a submount and a semiconductor laser element mounted on the submount. Semiconductor laser devices are used as light sources for products in various fields, such as projectors, automotive headlamps, and laser processing equipment. In this type of semiconductor laser device, the use of a porous metal material as a joining member for joining the semiconductor laser element and the submount has been proposed (see, for example, Patent Documents 1 and 2). Such joining members are formed by sintering a metal paste containing minute metal particles.

[0003] By using such a joining member, the thermal conductivity between the semiconductor laser element and the submount can be increased, and therefore the heat dissipation characteristics of the semiconductor laser device can be improved.

[0004] JP 2015-188034 A JP 2006-202586 A

[0005] However, if such a joining member is attached to the side surface of the semiconductor laser element, there is a risk of current leakage between the p-type semiconductor layer and the n-type semiconductor layer of the semiconductor laser element.

[0006] The present disclosure has been made to solve such problems, and has an object to provide a semiconductor laser device and the like that can reduce current leakage in a semiconductor laser element.

[0007] In order to achieve the above object, one aspect of the semiconductor laser device according to the present disclosure is a semiconductor laser device that emits laser light, comprising: a submount having a mounting surface; a spacer disposed on the mounting surface; an edge-emitting semiconductor laser element disposed above the spacer; and a bonding member made of a porous metal material that is disposed between the spacer and the semiconductor laser element and bonds the spacer to the semiconductor laser element, the semiconductor laser element having front and rear end faces that form a resonator of the laser light, an opposing surface that faces the submount, a substrate, and a semiconductor laminate disposed between the substrate and the opposing surface, the spacer is not present outside one end of the semiconductor laser element in a first direction perpendicular to the resonance direction of the laser light in a plan view of the mounting surface, the bonding member is disposed between the one end of the semiconductor laser element and one end of the spacer in the first direction in a plan view of the mounting surface, and the opposing surface at the one end of the semiconductor laser element is exposed from the bonding member.

[0008] In order to achieve the above object, one aspect of a method for manufacturing a semiconductor laser device according to the present disclosure is a method for manufacturing a semiconductor laser device that emits laser light, the semiconductor laser device comprising: a submount having a mounting surface; a spacer; an edge-emitting semiconductor laser element; and a joining member made of a porous metal material that is arranged between the spacer and the semiconductor laser element and joins the spacer and the semiconductor laser element, the semiconductor laser element having front and rear end faces that form a resonator of the laser light, an opposing surface that faces the mounting surface, a substrate, and a semiconductor laminate that is arranged between the substrate and the opposing surface, and The spacer is not present outside one end in a first direction perpendicular to the oscillation direction, the joining member is arranged between the one end of the semiconductor laser element and the spacer in a planar view of the mounting surface, and the opposing surface at the one end of the semiconductor laser element is exposed from the joining member, and a method for manufacturing the semiconductor laser device includes a spacer arrangement step of arranging the spacer on the mounting surface, a paste arrangement step of arranging a metal paste containing metal particles on the spacer, a pressing step of pressing the opposing surface of the semiconductor laser element against the metal paste while the opposing surface is facing the metal paste, and a heating step of heating the metal paste to form the joining member.

[0009] According to the present disclosure, it is possible to provide a semiconductor laser device or the like that can reduce current leakage in a semiconductor laser element.

[0010] 1 is a schematic first plan view showing the overall configuration of a semiconductor laser device according to a first embodiment. FIG. 2 is a schematic first plan view showing the overall configuration of a semiconductor laser device according to a first embodiment. FIG. 3 is a schematic first cross-sectional view showing the overall configuration of a semiconductor laser device according to a first embodiment. FIG. 4 is a schematic cross-sectional view showing the overall configuration of a semiconductor laser element according to a first embodiment. FIG. 5 is a schematic cross-sectional view showing a submount preparation step in a method for manufacturing a semiconductor laser device according to a first embodiment. FIG. 6 is a schematic plan view showing a spacer arrangement step in a method for manufacturing a semiconductor laser device according to a first embodiment. FIG. 7 is a schematic cross-sectional view showing a spacer arrangement step in a method for manufacturing a semiconductor laser device according to a first embodiment. FIG. 8 is a schematic cross-sectional view showing a paste arrangement step in a method for manufacturing a semiconductor laser device according to a first embodiment. FIG. 9 is a schematic first cross-sectional view showing a pressing step in a method for manufacturing a semiconductor laser device according to a first embodiment. FIG. 10 is a schematic cross-sectional view showing a heating step in a method for manufacturing a semiconductor laser device according to a second embodiment. 10 is a schematic cross-sectional view showing a paste placement step in a manufacturing method for a semiconductor laser device according to a second embodiment. FIG. 11 is a schematic plan view showing a configuration of a semiconductor laser device according to a third embodiment. FIG. 12 is a schematic cross-sectional view showing a configuration of a semiconductor laser device according to a fourth embodiment. FIG. 13 is a schematic plan view showing a configuration of a semiconductor laser device according to a fifth embodiment. FIG. 14 is a schematic cross-sectional view showing a configuration of a semiconductor laser device according to the fifth embodiment. FIG. 15 is a schematic cross-sectional view showing a first example of a paste placement step in a manufacturing method for a semiconductor laser device according to the fifth embodiment. FIG. 16 is a schematic cross-sectional view showing a second example of a paste placement step in a manufacturing method for a semiconductor laser device according to a sixth embodiment. FIG. 17 is a schematic cross-sectional view showing a configuration of a semiconductor laser device according to a seventh embodiment.

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, arrangement and connection of the components, steps (processes), and order of steps shown in the following embodiments are merely examples and are not intended to limit the present disclosure.

[0012] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, the scales and the like do not necessarily match in each figure. In each figure, the same reference numerals are used to denote substantially the same components, and redundant explanations will be omitted or simplified.

[0013] In this specification, the terms "above" and "below" do not refer to vertically above and below in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in a stacked configuration. The terms "above" and "below" are used not only when two components are arranged with a gap between them and another component is present between them, but also when two components are arranged in contact with each other.

[0014] Furthermore, in this specification, terms indicating the relationship between elements, such as parallel and perpendicular, terms indicating the shape of elements, such as rectangular, rectangular, trapezoidal, plate-like, and flat, and numerical ranges are not expressions that only express a strict meaning, but are expressions that also include a substantially equivalent range, for example, a difference of about a few percent.

[0015] First Embodiment A semiconductor laser device according to a first embodiment and a method for manufacturing the same will be described.

[0016] [1-1. Overall Configuration of Semiconductor Laser Device] First, the overall configuration of a semiconductor laser device 10 according to this embodiment will be described with reference to FIGS. 1 to 4. FIGS. 1 and 2 are schematic plan views showing the overall configuration of the semiconductor laser device 10 according to this embodiment. FIGS. 1 and 2 show plan views of the semiconductor laser device 10 in a plan view of the mounting surface 80a of the submount 80. In FIG. 2, only the outline of the semiconductor laser element 20 is shown with a dashed line to illustrate the configuration of the bonding member 60. Also, in FIG. 2, the outline of the spacer 40 is shown with a dashed line. FIG. 3 is a schematic cross-sectional view showing the overall configuration of the semiconductor laser device 10 according to this embodiment. FIG. 3 shows a cross section of the semiconductor laser device 10 taken along line III-III in FIG. 1. FIG. 4 is a schematic cross-sectional view showing the overall configuration of the semiconductor laser device 10 according to this embodiment. FIG. 4 shows a cross section of the semiconductor laser device 10 taken along line IV-IV in FIG. 1. Each figure shows an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other. The X-axis, Y-axis, and Z-axis are in a right-handed Cartesian coordinate system. The Y-axis direction is parallel to the resonance direction (and emission direction) of the laser light L0 emitted by the semiconductor laser device 10. The Z-axis direction is perpendicular to the mounting surface 80a of the submount 80.

[0017] 1, 2, and 4, a semiconductor laser device 10 according to the present embodiment is a device that emits laser light L0. As shown in FIGS. 1 to 4, the semiconductor laser device 10 includes a submount 80, a spacer 40, a semiconductor laser element 20, and a bonding member 60.

[0018] The submount 80 is a base having a mounting surface 80a, on which the semiconductor laser element 20 is mounted. In this embodiment, the submount 80 has a substrate 81 and a pad electrode 82.

[0019] The substrate 81 is a main component of the submount 80. The shape of the substrate 81 is, for example, a rectangular parallelepiped. The substrate 81 and pad electrodes 82 of the submount 80 also function as a heat sink for dissipating heat generated by the semiconductor laser element 20. Therefore, the material of the substrate 81 may be either a conductive material or an insulating material, but it is preferable that the substrate 81 be made of a material with high thermal conductivity. The thermal conductivity of the submount 80 is preferably, for example, 150 W / (m·K) or higher. For example, the substrate 81 of the submount 80 may be made of a ceramic such as aluminum nitride (AlN) or polycrystalline silicon carbide (SiC), a metal material such as Cu, or a single-crystal diamond or polycrystalline diamond.

[0020] The pad electrode 82 is an electrode disposed on the main surface of the substrate 81. In the present embodiment, the pad electrode 82 is a conductive film. The pad electrode 82 may be a single-layer film or a multi-layer film made of, for example, Au, Ag, Cu, Pt, Pb, Ni, Cr, W, Mo, or Ti. In the present embodiment, the upper surface of the pad electrode 82 (the surface behind the surface of the pad electrode 82 that is bonded to the substrate 81) is the mounting surface 80a. The mounting surface 80a is, for example, a flat surface, but is not limited to this.

[0021] The semiconductor laser element 20 is an edge-emitting type laser element disposed above the spacer 40. The configuration of the semiconductor laser element 20 will be described using FIG. 5 in addition to FIGS. 1 to 4 . FIG. 5 is a schematic cross-sectional view showing the overall configuration of the semiconductor laser element 20 according to this embodiment. FIG. 5 shows a cross-section of the semiconductor laser element 20 at the same position as in FIG. 3 . As shown in FIGS. 1 and 2 , the semiconductor laser element 20 has a front end face 20F and a rear end face 20R that form a resonator for laser light L0. As shown in FIG. 5 , the semiconductor laser element 20 also has an opposing surface 20a that faces the submount 80, a substrate 22, and a semiconductor stack 20S. In this embodiment, the semiconductor laser element 20 further has an insulating film 26, a first electrode 21, and a second electrode 27. The semiconductor laser element 20 also has an optical waveguide formed between the front end face 20F and the rear end face 20R, through which the laser light L0 is guided.

[0022] The semiconductor laser element 20 has an elongated shape with the resonance direction (i.e., the optical axis direction of the laser light L0) as the longitudinal direction. As an example, the length of the semiconductor laser element 20 in the resonance direction is 1200 μm, but is not limited to this.

[0023] The semiconductor laser element 20 is mounted on the mounting surface 80a of the submount 80 via a spacer 40 and a bonding member 60. In this embodiment, the semiconductor laser element 20 is electrically connected to a pad electrode 82 on the submount 80 via the bonding member 60. The spacer 40 may also be electrically interposed between the semiconductor laser element 20 and the pad electrode 82. In this embodiment, the semiconductor laser element 20 is mounted on the submount 80 by junction-down mounting.

[0024] 1 and 2, the semiconductor laser element 20 is mounted so that the front end face 20F protrudes beyond the edge of the mounting surface 80a. That is, in a plan view of the mounting surface 80a, the semiconductor laser element 20 protrudes from the mounting surface 80a, and the front end face 20F is located closer to the light emission side of the semiconductor laser element 20 than the edge of the mounting surface 80a of the submount 80. The protrusion amount of the semiconductor laser element 20 (i.e., the distance from the edge of the mounting surface 80a of the submount 80 to the front end face 20F of the semiconductor laser element 20) is, for example, not limited to, 5 μm or more and 20 μm or less. In this embodiment, the protrusion amount of the semiconductor laser element 20 is 10 μm.

[0025] As shown in FIG. 5 , the semiconductor stack 20S is a stack disposed between the substrate 22 and the opposing surface 20a. The semiconductor stack 20S includes a first semiconductor layer 23, an active layer 24, and a second semiconductor layer 25 disposed above the substrate 22. The first semiconductor layer 23 is a semiconductor layer of a first conductivity type. In this embodiment, the first conductivity type is n-type. The first semiconductor layer 23 includes, for example, an n-type cladding layer. The active layer 24 is a light-emitting layer that generates light. The second semiconductor layer 25 is a semiconductor layer of a second conductivity type different from the first conductivity type. In this embodiment, the second conductivity type is p-type. The second semiconductor layer 25 includes, for example, a p-type cladding layer and a p-type contact layer. The second semiconductor layer 25 has a ridge 25R and two protrusions 25P formed therein. The ridge 25R and the two protrusions 25P protrude away from the substrate 22 and extend in the resonance direction. A ridge 25R is formed with the same width (width in the X-axis direction perpendicular to the resonance direction) over the entire length between the front end face 20F and the rear end face 20R. The ridge 25R is disposed between two protruding portions 25P. A groove-shaped recess is formed between the ridge 25R and the two protruding portions 25P. The protruding amounts of the ridge 25R and the two protruding portions 25P are equal. The ridge 25R corresponds to an optical waveguide that guides the laser light L0.

[0026] The insulating film 26 is a member disposed above the semiconductor stack 20S. In this embodiment, the insulating film 26 electrically insulates the semiconductor stack 20S from a portion of the second electrode 27 excluding a region facing the opening 26a. The insulating film 26 has an opening 26a formed in a position facing a region including the central portion of the ridge 25R. In FIG. 1 , the outline of the opening 26a is indicated by a dashed line. The opening 26a extends along the upper surface of the ridge 25R. The opening 26a may or may not be surrounded by the insulating film 26 in a top view of the semiconductor stack 20S. For example, the opening 26a may be a slit dividing the insulating film 26.

[0027] The insulating film 26 covers the region of the upper surface of the semiconductor laminate 20S other than the opening 26a. That is, the insulating film 26 covers the region of the upper surface of the semiconductor laminate 20S other than the ridge 25R (i.e., the protruding portion 25P and the recessed portion adjacent to the protruding portion 25P), the side surface of the ridge 25R, and the edge portion of the upper surface of the ridge 25R. The insulating film 26 is made of, for example, SiO ２ It is made up of insulating materials such as:

[0028] The first electrode 21 is an electrode disposed on the substrate 22. The first electrode 21 is disposed on the main surface of the substrate 22, which is on the back side of the main surface on which the semiconductor laminate 20S is laminated. In the present embodiment, the first electrode 21 has an adhesion layer 21a and a pad electrode 21b. The adhesion layer 21a is a conductive layer disposed on the substrate 22. In the present embodiment, the adhesion layer 21a is made of a conductive material such as Ti that has good adhesion to the substrate 22. The pad electrode 21b is a conductive layer disposed on the adhesion layer 21a. In the present embodiment, the pad electrode 21b is made of a metal material such as Au.

[0029] The second electrode 27 is an electrode disposed above the semiconductor laminate 20S. In the present embodiment, the second electrode 27 contacts the semiconductor laminate 20S at the opening 26a in the insulating film 26. A current is injected from the second electrode 27 into a region of the upper surface of the ridge 25R of the semiconductor laminate 20S that contacts the second electrode 27. The second electrode 27 has a contact electrode 27a, an adhesion layer 27b, and a pad electrode 27c.

[0030] The contact electrode 27a is a conductive layer in contact with the semiconductor laminate 20S. In this embodiment, the contact electrode 27a is disposed in the opening 26a of the insulating film 26. The contact electrode 27a is made of, for example, Ag or Pd.

[0031] The adhesion layer 27b is a conductive layer disposed above the contact electrode 27a. In the present embodiment, the adhesion layer 27b is disposed above the contact electrode 27a and the insulating film 26, and is in contact with the contact electrode 27a and the insulating film 26. The adhesion layer 27b may be made of a material that has good adhesion to the insulating film 26. The adhesion layer 27b is made of, for example, Ti.

[0032] The pad electrode 27c is a conductive layer disposed above the adhesive layer 27b. In this embodiment, the pad electrode 27c is in contact with the adhesive layer 27b. The pad electrode 27c is made of, for example, Au.

[0033] The facing surface 20a is the surface of the semiconductor laser element 20 that faces the submount. As shown in FIG. 5 , the facing surface 20a has an electrode surface 30. The electrode surface 30 is the surface of the second electrode 27 that faces the submount 80. The electrode surface 30 has an implantation region 30a and a non-implantation region (i.e., a region including a first non-implantation region 31 and a second non-implantation region 32). Here, the region obtained by orthogonally projecting the contact electrode 27a onto the electrode surface 30 is referred to as the implantation region 30a. The implantation region 30a corresponds to a region of the semiconductor stack 20S into which current is injected from the electrode surface 30 via the contact electrode 27a, and extends in the resonance direction of the laser light. In this embodiment, the implantation region 30a is a region of the electrode surface 30 that faces the opening 26a and has the same planar shape as the opening 26a (i.e., the shape in a planar view of the mounting surface 80a). In this embodiment, implanted region 30a protrudes from non-protruding portions 31b, 32b of the non-implanted regions by a height H1. In this embodiment, implanted region 30a is a region of electrode surface 30 that faces a part of the upper surface of ridge 25R.

[0034] A region of the electrode surface 30 that is arranged along the implanted region 30a will be referred to as a non-implanted region. In this embodiment, the non-implanted region is a region of the electrode surface 30 other than the implanted region 30a. In this embodiment, the non-implanted region is a region facing the portion of the second electrode 27 that contacts the insulating film 26. The non-implanted region includes a first non-implanted region 31 and a second non-implanted region 32. The implanted region 30a is arranged between the first non-implanted region 31 and the second non-implanted region 32. The first non-implanted region 31 includes a non-protruding portion 31b and a protruding portion 31p that protrudes from the non-protruding portion 31b toward the submount 80. The second non-implanted region 32 includes a non-protruding portion 32b and a protruding portion 32p that protrudes from the non-protruding portion 32b toward the submount 80. Thus, the non-implantation region has non-protruding portions 31b, 32b and protruding portions 31p, 32p that protrude from the non-protruding portions 31b, 32b toward the submount 80. A height H1 from the non-protruding portions 31b, 32b to the protruding portions 31p, 32p is equal to the height from the non-protruding portions 31b, 32b to the implantation region 30a.

[0035] 1 to 4, the spacer 40 is a member disposed on the mounting surface 80a of the submount 80. The semiconductor laser element 20 is disposed above the spacer 40. The spacer 40 according to this embodiment will be described with reference to FIGS.

[0036] As shown in FIG. 3 , the spacer 40 is disposed on the opposing surface 20 a of the semiconductor laser element 20 at a position facing the electrode surface 30. In this embodiment, the spacer 40 is disposed at a position facing the injection region 30 a and has a rectangular parallelepiped (rectangular plate) shape. As shown in FIG. 2 , in a plan view of the mounting surface 80 a, the spacer 40 is not present outside one end of the semiconductor laser element 20 in a direction perpendicular to the resonance direction of the laser light (hereinafter also referred to as the first direction). Here, in a plan view of the mounting surface 80 a, one end of the semiconductor laser element 20 in the first direction corresponds to the side surface 20 sa, one of the two side surfaces 20 sa and 20 sb located at the ends of the semiconductor laser element 20 in the first direction. In addition, in a plan view of the mounting surface 80 a, one end of the spacer 40 in the first direction is disposed between one end of the semiconductor laser element 20 in the first direction and the injection region 30 a. In a plan view of the mounting surface 80a, one end of the spacer 40 in the first direction is disposed between one end of the semiconductor laser element 20 in the first direction and the ridge 25R.

[0037] In this embodiment, in a plan view of the mounting surface 80a, the spacer 40 does not exist outside the other end in the first direction of the semiconductor laser element 20. Here, in a plan view of the mounting surface 80a, the other end in the first direction of the semiconductor laser element 20 corresponds to the side surface 20sb of the two side surfaces 20sa and 20sb. In addition, in a plan view of the mounting surface 80a, the other end in the first direction of the spacer 40 is disposed between the other end in the first direction of the semiconductor laser element 20 and the injection region 30a. In a plan view of the mounting surface 80a, the other end in the first direction of the spacer 40 is disposed between the other end in the first direction of the semiconductor laser element 20 and the ridge 25R.

[0038] The width of the spacer 40 in the first direction (i.e., the distance between two side surfaces 40sa, 40sb, which are two end surfaces of the spacer 40 in the first direction) is smaller than the width in the first direction of the semiconductor laser element 20. In this embodiment, the width of the spacer 40 in the first direction is equal to the width in the first direction of the top surface 40u, which is the surface of the spacer 40 facing the semiconductor laser element 20, but if these widths are different from each other, the width in the first direction of the top surface 40u may be smaller than the width in the first direction of the semiconductor laser element 20.

[0039] In addition, in a plan view of the mounting surface 80a, the spacers 40 do not protrude from the mounting surface 80a. In a plan view of the mounting surface 80a, the spacers 40 protrude outward (in the negative Y-axis direction) from the rear end face 20R.

[0040] 3, in a plan view of the mounting surface 80a, the end of the spacer 40 closest to the front end face 20F is located a distance d4 inward from the end of the mounting surface 80a. In this embodiment, the distance d4 is 5 μm.

[0041] The thickness H0 of the spacer 40 shown in FIG. 3 (that is, the height from the mounting surface 80a of the submount 80 to the upper surface 40u of the spacer 40) is, for example, 2 μm or more.

[0042] The thermal conductivity of the spacer 40 may be 50 W / (m·K) or more, and may be higher than the thermal conductivity of the joining member 60. This can improve the heat dissipation characteristics of the heat dissipation path that passes through the spacer 40.

[0043] The spacer 40 may be made of a metal material such as Au or Cu, or a non-metal material such as diamond-like carbon (DLC). The spacer 40 may be bonded to the mounting surface 80a or may be formed by vapor deposition on the mounting surface 80a.

[0044] The bonding member 60 is a conductive member made of a porous metal material and disposed between the spacer 40 and the semiconductor laser element 20 to bond the spacer 40 and the semiconductor laser element 20. The bonding member 60 is disposed between the injection region 30a and the mounting surface 80a. In other words, the bonding member 60 is disposed between the ridge 25R and the mounting surface 80a. The bonding member 60 is made of a porous metal material having voids (air gaps) with dimensions of approximately 1 μm or less. In this embodiment, the bonding member 60 is composed mainly of metal particles. In other words, the bonding member 60 is an aggregate of metal particles sintered while partially maintaining their particulate shape. Gaps between the sintered metal particles while partially maintaining their particulate shape form voids within the bonding member 60. These voids realize the porous bonding member 60. The bonding member 60 is formed, for example, by heating a metal paste containing metal particles with an average particle size of 1 μm or less (hereinafter simply referred to as particle size) and a solvent at a relatively low temperature of approximately 200° C. The particle diameter of the metal particles may be, for example, 10 nm or more and 500 nm or less. In this case, the size of the voids in the bonding member 60 is also 10 nm or more and 500 nm or less. This allows the metal particles to be sintered and bonded together. A detailed method for forming the bonding member 60 will be described later. The bonding member 60 is, for example, a sintered body of particles made of at least one material selected from Au, Ag, and Cu. Such a bonding member 60 can achieve a thermal conductivity of, for example, 50 W / (m·K) or more. This allows heat generated in the semiconductor laser element 20 to be efficiently conducted to the submount 80 via the bonding member 60. Furthermore, the thermal conductivity of the bonding member 60 may be equal to or greater than the thermal conductivity of the submount 80. This allows heat generated in the semiconductor laser element 20 to be more efficiently conducted to the submount 80 via the bonding member 60.

[0045] Furthermore, the bonding member 60 made of a porous metal material has high elasticity, and therefore can alleviate thermal distortion after the semiconductor laser element 20 is mounted on the submount 80 .

[0046] 3, in this embodiment, the bonding member 60 is bonded to the implantation region 30a. This allows current to be injected into the implantation region 30a via the bonding member 60. The bonding member 60 is bonded to the semiconductor laser element 20 at a bonding region 60r shown in FIG.

[0047] In a plan view of the mounting surface 80a, the area of ​​the bonding region 60r may be 50% or more of the area of ​​the semiconductor laser element 20 (i.e., the area of ​​the semiconductor laser element 20 in a plan view of the mounting surface 80a). In this way, by increasing the ratio of the area of ​​the bonding region 60r to the area of ​​the semiconductor laser element 20, the bonding strength between the semiconductor laser element 20 and the bonding member 60 can be increased.

[0048] The distance d1 shown in FIG. 1 represents the distance from the rear end face 20R to the bonding region 60r, the distance d2 represents the distance from the front end face 20F to the bonding region 60r, and the distance d3 represents the distance from one end of the semiconductor laser element 20 in the first direction to the bonding region 60r.

[0049] The distance d1 is equal to or greater than 0. In this embodiment, the distance d1 is 0.

[0050] The distance d2 is greater than 0. The distance d2 may also be greater than the distance d1. By making the distance d2 greater than 0 or the distance d1 in this manner, it is possible to reduce adhesion of the joining member 60 to the front end surface 20F. Therefore, it is possible to reduce blocking of the laser light L0 by the joining member 60. In this embodiment, the distance d2 is 15 μm.

[0051] The distance d3 is greater than 0. Alternatively, the distance d3 may be greater than the distance d1 or the distance d2. This reduces adhesion of the joining member 60 to the side surface 20sa. Therefore, current leakage in the semiconductor laser device 20 can be reduced.

[0052] As described above, the spacer 40 is not present outside one end of the semiconductor laser element 20 in the first direction. In this way, the distance between the one end of the semiconductor laser element 20 in the first direction and the spacer 40 can be made larger than the distance between the injection region 30a and the spacer 40. Therefore, even if the bonding member 60 is disposed between one end of the semiconductor laser element 20 in the first direction and one end of the spacer 40 in the first direction in the plan view of the mounting surface 80a as shown in FIG. 2 (i.e., between one end of the semiconductor laser element 20 in the first direction and the spacer 40), the facing surface 20a can be exposed from the bonding member 60 at one end of the semiconductor laser element 20 in the first direction as shown in FIG. 3. That is, as shown in FIG. 1, the distance d3 is greater than 0 in the plan view of the mounting surface 80a. In this way, the bonding member 60 is not disposed at one end of the facing surface 20a of the semiconductor laser element 20 in the first direction, which reduces adhesion of the bonding member 60 to the side surface 20sa. Therefore, current leakage in the semiconductor laser device 20 can be reduced.

[0053] In this embodiment, the spacer 40 is not present outside the other end of the semiconductor laser element 20 in the first direction. In this way, the distance between the other end of the semiconductor laser element 20 in the first direction and the spacer 40 can be made larger than the distance between the injection region 30a and the spacer 40. Therefore, even if a bonding member 60 is disposed between the other end of the semiconductor laser element 20 in the first direction and the other end of the spacer 40 in the first direction (i.e., between the other end of the semiconductor laser element 20 in the first direction and the spacer 40) in a plan view of the mounting surface 80a as shown in FIG. 2 , the opposing surface 20a can be exposed from the bonding member 60 at the other end of the semiconductor laser element 20 in the first direction, as shown in FIG. 3 . Since the bonding member 60 is not disposed at the other end of the opposing surface 20a of the semiconductor laser element 20 in the first direction, adhesion of the bonding member 60 to the side surface 20sb can be reduced. This reduces current leakage in the semiconductor laser element 20.

[0054] 2 , in the present embodiment, the bonding member 60 is disposed in a region of the mounting surface 80a that is located between one end of the semiconductor laser element 20 in the first direction and one end of the spacer 40 in the first direction in a plan view of the mounting surface 80a (i.e., the region that is located between one end of the semiconductor laser element 20 in the first direction and the spacer 40). This allows the semiconductor laser element 20 and the submount 80 to be bonded together by the bonding member 60, which has high thermal conductivity, and therefore allows efficient heat dissipation from the semiconductor laser element 20 to the submount 80. Furthermore, because the bonding member 60 is bonded not only to the spacer 40 but also to the submount 80, the bonding between the bonding member 60 and the spacer 40 and the submount 80 can be strengthened.

[0055] The bonding member 60 is continuously disposed in a region of the mounting surface 80a adjacent to one end of the spacer 40 in the first direction, on a side surface 40sa located at one end of the spacer 40 in the first direction, between the spacer 40 and the semiconductor laser element 20, on a side surface 40sb located at the other end of the spacer 40 in the first direction, and on a region of the mounting surface 80a adjacent to the other end of the spacer 40 in the first direction. This allows the semiconductor laser element 20 and the submount 80 to be bonded together with the bonding member 60 having high thermal conductivity, thereby enabling efficient heat dissipation from the semiconductor laser element 20 to the submount 80. Furthermore, because the bonding member 60 is bonded not only to the spacer 40 but also to the submount 80, the bonding between the bonding member 60 and the spacer 40 and the submount 80 can be strengthened.

[0056] The space between one end of the spacer 40 in the first direction and the semiconductor laser element 20 is filled with the bonding member 60. That is, the space between the semiconductor laser element 20 and the end of one side surface 40sa of the spacer 40 that is closer to the semiconductor laser element 20 is filled with the bonding member 60. The gap G0 between the one end of the spacer 40 in the first direction and the semiconductor laser element 20 is smaller than the thickness H0 of the spacer 40. This reduces the thermal resistance between the semiconductor laser element 20 and the spacer 40. Therefore, the heat dissipation characteristics from the semiconductor laser element 20 to the spacer 40 can be improved.

[0057] 1 and 2 , in a plan view of the mounting surface 80a, the bonding member 60 is not present outside one end of the semiconductor laser element 20 in the first direction. Furthermore, in a plan view of the mounting surface 80a, the bonding member 60 is not present outside the other end of the semiconductor laser element 20 in the first direction. This further reduces adhesion of the bonding member 60 to the side surfaces 20sa and 20sb. Therefore, current leakage in the semiconductor laser element 20 can be further reduced.

[0058] In this embodiment, the facing surface 20a of the semiconductor laser element 20 has an injection region 30a that corresponds to a region of the semiconductor laminate 20S into which current is injected from the facing surface 20a, and that extends in the resonance direction of the laser light, and a spacer 40 is arranged between the injection region 30a and the mounting surface 80a. In other words, the spacer 40 is arranged between the ridge 25R and the mounting surface 80a. This allows the bonding member 60, which is arranged between the semiconductor laser element 20 and the spacer 40, to be reliably bonded to the injection region 30a. Therefore, current can be reliably injected into the injection region 30a via the bonding member 60.

[0059] [1-2. Manufacturing Method of Semiconductor Laser Device] A manufacturing method of the semiconductor laser device 10 according to this embodiment will be described with reference to FIGS. 6 to 12. FIGS. 6, 8 to 12 are schematic cross-sectional views showing each step of the manufacturing method of the semiconductor laser device 10 according to this embodiment. FIGS. 6, 8 to 12 show cross sections of the submount 80 and other components at the same position as in FIG. 2. FIG. 7 is a schematic plan view showing the spacer placement step of the manufacturing method of the semiconductor laser device 10 according to this embodiment. FIG. 7 shows a plan view of the submount 80 and the spacer 40 in a plan view of the mounting surface 80a of the submount 80.

[0060] 6, first, a submount 80 having a mounting surface 80a is prepared (submount preparation step). In this embodiment, the submount 80 is formed by depositing a pad electrode 82 on the main surface of a substrate 81.

[0061] 7 and 8, the spacer 40 is placed on the mounting surface 80a of the submount 80 (spacer placement step). As the spacer 40, a plate-like member may be placed on the mounting surface 80a, or the spacer 40 may be formed on the mounting surface 80a by plating, vapor deposition, or the like.

[0062] Next, as shown in FIG. 9, a metal paste 60p containing metal particles is placed on the spacer 40 (i.e., on the upper surface 40u of the spacer 40) (paste placing step). The metal paste 60p is a paste containing metal particles, a solvent, and a surfactant. The particle size of the metal particles is 1 μm or less. The metal paste 60p contains particles made of at least one material selected from Au, Ag, and Cu, for example. In this embodiment, the metal particles are made of Au. The solvent contained in the metal paste 60p is, for example, an ester alcohol (2,2,4-trimethyl-3-hydroxypentaisobutyrate:C １２ H ２４ O ３ ), terpineol, pine oil, butyl carbitol acetate, butyl carbitol, carbitol, and other organic solvents. The surfactants are, for example, alkylamines (CH ３ (CH ２ ) ｎ NH ２ ), alkylamine carboxylate, carboxylic acid amide, ester amine, organic titanium compound, sodium sulfocarboxylate, etc. Such metal paste 60p can be applied onto the mounting surface 80a by, for example, a dispenser method.

[0063] In the present embodiment, in the paste disposing step, the metal paste 60p is disposed only on the spacer 40. The metal paste 60p extends in the Y-axis direction. The width of the metal paste 60p in the first direction may be equal to the width of the upper surface 40u of the spacer 40.

[0064] 10 , the facing surface 20a of the semiconductor laser element 20 is pressed against the metal paste 60p with the facing surface 20a facing the metal paste 60p (pressing step). In this embodiment, in the pressing step, the injection region 30a is pressed against the metal paste 60p with the injection region 30a facing the metal paste 60p. In the pressing step, the metal paste 60p is disposed between one end of the semiconductor laser element 20 and the spacer 40 in a plan view of the mounting surface 80a, as shown in FIG. 11 . That is, in the pressing step, the metal paste 60p is crushed and pushed out onto the side surfaces 40sa and 40sb of the spacer 40 and onto the mounting surface 80a, as shown in FIG.

[0065] Next, as shown in FIG. 12 , the metal paste 60p is heated to form the bonding member 60 (see FIG. 3 , etc.) (heating process). In this embodiment, heating at a relatively low temperature of about 200°C evaporates the solvent and sinters the metal particles, fusing adjacent metal particles together. This results in the formation of a porous metal paste 60p in which almost only the metal particles remain. Because the particle size of the metal particles is 1 μm or less, the melting point of the metal is lowered due to the size effect. This allows the metal particles to be sintered by heating them at a relatively low temperature of about 200°C. The bonding member 60 made of such a porous metal material has high elasticity, which can alleviate thermal strain after mounting the semiconductor laser element 20 on the submount 80. Furthermore, the load on the implantation region 30a bonded by the bonding member 60 can be reduced.

[0066] Through the steps described above, the semiconductor laser device 10 according to this embodiment can be manufactured.

[0067] As described above, in this embodiment, the semiconductor laser element 20 is bonded to the mounting surface 80a via the spacer 40 using the bonding member 60. Here, in a plan view of the mounting surface 80a, the spacer 40 is not present outside one end of the semiconductor laser element 20 in the first direction, so that the facing surface 20a can be exposed from the bonding member 60 at one end of the semiconductor laser element 20. This makes it possible to reduce adhesion of the bonding member 60 (or the metal paste 60p) to the side surface 20sa. Therefore, the manufacturing method for the semiconductor laser device 10 according to this embodiment makes it possible to reduce current leakage in the semiconductor laser element 20.

[0068] Furthermore, in this embodiment, as described above, in the paste placement step, the metal paste 60p is placed only on the spacer 40 above the mounting surface 80a. In the pressing step, the metal paste 60p is placed between one end of the semiconductor laser element 20 and the spacer 40 in a plan view of the mounting surface 80a. By placing the metal paste 60p only on the spacer 40 in this manner in the paste placement step, even if the metal paste 60p is crushed in the pressing step, the metal paste 60p is pushed out from the upper surface of the spacer 40 to the mounting surface 80a and does not immediately reach the vicinity of the side surfaces 20sa and 20sb. Therefore, leakage in the semiconductor laser element 20 caused by the metal paste 60p adhering to the side surfaces 20sa and 20sb can be further reduced.

[0069] Second Embodiment A semiconductor laser device according to a second embodiment and a manufacturing method thereof will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 10 according to the first embodiment in the configuration of the bonding member. The semiconductor laser device according to this embodiment will be described below with reference to FIGS. 13 and 14, focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIGS. 13 and 14 are a schematic plan view and a cross-sectional view, respectively, showing the configuration of a semiconductor laser device 110 according to this embodiment. FIG. 13 shows a plan view of the semiconductor laser device 110 in a plan view of the mounting surface 80a of the submount 80. FIG. 14 shows a cross section of the semiconductor laser device 110 taken along line XIV-XIV in FIG. 13.

[0070] As shown in FIGS. 13 and 14, a semiconductor laser device 110 according to this embodiment includes a submount 80, a spacer 40, a semiconductor laser element 20, and a bonding member 160.

[0071] 13 , the bonding member 160 is bonded to the semiconductor laser element 20 in a bonding region 160r. In a plan view of the mounting surface 80a, the bonding member 160 protrudes outward from one end of the semiconductor laser element 20 in the first direction. The bonding member 160 also protrudes outward from the other end of the semiconductor laser element 20 in the first direction.

[0072] In the semiconductor laser device 110 according to this embodiment, the facing surface 20a is also exposed from the bonding member 160 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, the bonding member 160 is not disposed at one and the other ends in the first direction of the facing surface 20a of the semiconductor laser element 20, so that adhesion of the bonding member 160 to the side surfaces 20sa, 20sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0073] Furthermore, in this embodiment, as described above, in a plan view of the mounting surface 80a, the bonding member 160 protrudes outward from one end in the first direction of the semiconductor laser element 20. Even when using a bonding member 160 having such a configuration, the spacer 40 ensures a space between the mounting surface 80a and the semiconductor laser element 20, thereby reducing adhesion of the bonding member 160 to the side surfaces 20sa and 20sb. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0074] Furthermore, in this embodiment, the contact area between the bonding member 160 and the mounting surface 80a can be increased compared to the first embodiment, thereby increasing the bonding strength between the bonding member 160 and the submount 80. Furthermore, in this embodiment, the heat dissipation characteristics from the bonding member 160 to the submount 80 can be improved.

[0075] 14 , in the present embodiment, the thickness T0 of the bonding member 160 located between one end of the semiconductor laser element 20 in the first direction and the mounting surface 80a is smaller than the thickness H0 of the spacer 40. This makes it possible to more reliably reduce adhesion of the bonding member 160 to the side surface 20sa.

[0076] Furthermore, in this embodiment, the thickness T0 of the bonding member 160 located between one end of the semiconductor laser element 20 in the first direction and the mounting surface 80a is larger than the gap G0 between one end of the spacer 40 in the first direction and the semiconductor laser element 20. In this way, by increasing the thickness T0 of the bonding member 160, heat can be reliably dissipated to an area outside the semiconductor laser element 20 in a plan view of the mounting surface 80a. Therefore, the heat dissipation characteristics of the bonding member 160 can be improved.

[0077] A method for manufacturing the semiconductor laser device 110 according to this embodiment will be described. The method for manufacturing the semiconductor laser device 110 according to this embodiment differs from the method for manufacturing the semiconductor laser device 10 according to the first embodiment in the paste placement step. The paste placement step according to this embodiment will be described below with reference to FIG. 15. FIG. 15 is a schematic cross-sectional view showing the paste placement step in the method for manufacturing the semiconductor laser device 110 according to this embodiment. FIG. 15 shows cross sections of the submount 80, the spacer 40, and the metal paste 160p at the same positions as in FIG. 14.

[0078] 15 , in the paste placement step of the manufacturing method for the semiconductor laser device 110 according to the present embodiment, a metal paste 160p similar to the metal paste 60p according to the first embodiment is continuously placed on the spacer 40 and the mounting surface 80a. In the present embodiment, the amount of the metal paste 160p is increased compared to the amount of the metal paste 60p placed in the paste placement step according to the first embodiment. Accordingly, in the example shown in FIG. 15 , a portion of the metal paste 160p is placed on the mounting surface 80a in the paste placement step. That is, a portion of the metal paste 160p comes into contact with the mounting surface 80a in the paste placement step.

[0079] By the method for manufacturing the semiconductor laser device 110 according to this embodiment, which includes the paste placement step, it is possible to manufacture the semiconductor laser device 110 as shown in Figures 13 and 14. The method for manufacturing the semiconductor laser device 110 as described above provides the same effects as those of the semiconductor laser device 110 described above.

[0080] It should be noted that the paste placement process according to this embodiment is not limited to the process described above. For example, even if the metal paste 160p is placed only on the upper surface of the spacer 40 above the mounting surface 80a, the semiconductor laser device 110 according to this embodiment may be manufactured. For example, if the viscosity of the metal paste 160p is high, a relatively large amount of the metal paste 160p can be placed only on the upper surface of the spacer 40. In this way, if the metal paste 160p can be sufficiently placed only on the upper surface of the spacer 40, the metal paste 160p may be placed only on the upper surface of the spacer 40 above the mounting surface 80a in the paste placement process.

[0081] Third Embodiment A semiconductor laser device according to a third embodiment and a manufacturing method thereof will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 10 according to the first embodiment in the configuration of the bonding member. The semiconductor laser device according to this embodiment will be described below with reference to FIGS. 16 and 17, focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIGS. 16 and 17 are a schematic plan view and a cross-sectional view, respectively, showing the configuration of a semiconductor laser device 210 according to this embodiment. FIG. 16 shows a plan view of the semiconductor laser device 210 in a plan view of the mounting surface 80a of the submount 80. FIG. 17 shows a cross section of the semiconductor laser device 210 taken along line XVII-XVII in FIG. 16.

[0082] As shown in FIGS. 16 and 17, a semiconductor laser device 210 according to this embodiment includes a submount 80, a spacer 40, a semiconductor laser element 20, and a bonding member 260.

[0083] 16 , the bonding member 260 is bonded to the semiconductor laser element 20 in a bonding region 260r. In a plan view of the mounting surface 80a, the bonding member 260 does not exist outside one end in the first direction of the semiconductor laser element 20. In addition, in a plan view of the mounting surface 80a, the bonding member 260 does not exist outside the other end in the first direction of the semiconductor laser element 20.

[0084] 17 , in the present embodiment, a bonding member 260 is disposed on a side surface 40sa located at one end of the spacer 40 in the first direction, and an end of the side surface 40sa close to the mounting surface 80a is exposed from the bonding member 260. In other words, the bonding member 260 is not disposed near the bottom end of the side surface 40sa or on the mounting surface 80a shown in FIG. 17 . Similarly, a bonding member 260 is disposed on a side surface 40sb located at the other end of the spacer 40 in the first direction, and an end of the side surface 40sb close to the mounting surface 80a is exposed from the bonding member 260.

[0085] In the semiconductor laser device 210 according to this embodiment, the facing surface 20a is also exposed from the bonding member 260 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, the bonding member 260 is not disposed at one and the other ends in the first direction of the facing surface 20a of the semiconductor laser element 20, so that adhesion of the bonding member 260 to the side surfaces 20sa, 20sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0086] Furthermore, in the present embodiment, in a plan view of the mounting surface 80a, the bonding member 260 is not present outside one end and the other end in the first direction of the semiconductor laser element 20. As a result, similar to the semiconductor laser device 10 according to the first embodiment, the semiconductor laser device 210 according to the present embodiment can also reduce adhesion of the bonding member 260 to the side surfaces 20sa, 20sb. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0087] Furthermore, a bonding member 260 is disposed on a side surface 40sa located at one end of the spacer 40 in the first direction, and an end of the side surface 40sa close to the mounting surface 80a is exposed from the bonding member 260. Furthermore, a bonding member 260 is disposed on a side surface 40sb located at the other end of the spacer 40 in the first direction, and an end of the side surface 40sb close to the mounting surface 80a is exposed from the bonding member 260.

[0088] Since the bonding member 260 is not disposed on the mounting surface 80a, the bonding member 260 is less likely to reach the side surfaces 20sa and 20sb. This reduces adhesion of the bonding member 260 to the side surfaces 20sa and 20sb. This reduces current leakage in the semiconductor laser element 20.

[0089] A method for manufacturing the semiconductor laser device 210 according to this embodiment will be described. The method for manufacturing the semiconductor laser device 210 according to this embodiment differs from the method for manufacturing the semiconductor laser device 10 according to the first embodiment in the paste placement step. In the paste placement step of the method for manufacturing the semiconductor laser device 210 according to this embodiment, a metal paste similar to the metal paste 60p according to the first embodiment is placed on the spacer 40. Here, for example, the amount of metal paste is reduced compared to the amount of metal paste 60p placed in the paste placement step according to the first embodiment.

[0090] By the method for manufacturing the semiconductor laser device 210 according to this embodiment, which includes the paste placement step, it is possible to manufacture the semiconductor laser device 210 as shown in Figures 16 and 17. The method for manufacturing the semiconductor laser device 210 as described above provides the same effects as those of the semiconductor laser device 210 described above.

[0091] Fourth Embodiment A semiconductor laser device according to a fourth embodiment and a manufacturing method thereof will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 10 according to the first embodiment in the configuration of the bonding member. The semiconductor laser device according to this embodiment will be described below with reference to FIG. 18 , focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIG. 18 is a schematic plan view showing the configuration of a semiconductor laser device 310 according to this embodiment. FIG. 18 shows a plan view of the semiconductor laser device 310 in a plan view of the mounting surface 80 a of the submount 80. In FIG. 18 , in order to explain the configuration of the bonding member 360, a plan view of the semiconductor laser device 310 from which the semiconductor laser element 20 has been removed is shown, and only the outline of the semiconductor laser element 20 is indicated by a dashed line.

[0092] As shown in FIG. 18, a semiconductor laser device 310 according to this embodiment includes a submount 80 , a spacer 40 , a semiconductor laser element 20 , and a bonding member 360 .

[0093] In a plan view of the mounting surface 80a, one end 360sa of the bonding member 360 in the first direction has a portion that protrudes outward from one end of the semiconductor laser element 20 and a portion that does not protrude. For example, at the position of line A3-A3 in FIG. 18, one end 360sa of the bonding member 360 in the first direction protrudes outward from one end of the semiconductor laser element 20. In other words, the cross-sectional configuration of the bonding member 360 at the position of line A3-A3 in FIG. 18 is similar to the cross-sectional configuration of the bonding member 160 according to the second embodiment shown in FIG. 14. In this embodiment, in a plan view of the mounting surface 80a, at the center in the resonance direction of the semiconductor laser element 20, one end 360sa of the bonding member 360 in the first direction protrudes outward from one end of the semiconductor laser element 20 in the first direction.

[0094] 18, one end 360sa of the bonding member 360 in the first direction does not protrude outward from one end of the semiconductor laser element 20. The cross-sectional configuration of the bonding member 360 at the positions of the A2-A2 line and the A4-A4 line in FIG. 18 is similar to the cross-sectional configuration of the bonding member 60 according to the first embodiment shown in FIG.

[0095] At the positions of line A1-A1 and line A5-A5 in Fig. 18, one end 360sa of bonding member 360 in the first direction does not protrude outward from one end of semiconductor laser element 20. The cross-sectional configuration of bonding member 360 at the positions of line A1-A1 and line A5-A5 in Fig. 18 is similar to the cross-sectional configuration of bonding member 260 according to embodiment 3 shown in Fig. 17. In other words, bonding member 360 is disposed on side surfaces 40sa and 40sb located at one end of spacer 40 in the first direction, and the ends of side surfaces 40sa and 40sb close to mounting surface 80a are exposed from bonding member 360.

[0096] Similar to the one end 360sa, the other end 360sb of the bonding member 360 in the first direction has a portion that protrudes outward from the other end of the semiconductor laser element 20 and a portion that does not protrude. That is, at the position of line A3-A3 in Fig. 18, the other end 360sb of the bonding member 360 in the first direction protrudes outward from the other end of the semiconductor laser element 20. At the positions of lines A1-A1, A2-A2, A4-A4, and A5-A5 in Fig. 18, the other end 360sb of the bonding member 360 in the first direction does not protrude outward from the other end of the semiconductor laser element 20.

[0097] In the semiconductor laser device 310 according to this embodiment, the facing surface 20a is also exposed from the bonding member 360 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, the bonding member 360 is not disposed at one and the other ends in the first direction of the facing surface 20a of the semiconductor laser element 20, so that adhesion of the bonding member 360 to the side surfaces 20sa, 20sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0098] A manufacturing method of the semiconductor laser device 310 according to this embodiment will be described. The manufacturing method of the semiconductor laser device 310 according to this embodiment differs from the manufacturing method of the semiconductor laser device 10 according to the first embodiment in the paste placement step. In the paste placement step of the manufacturing method of the semiconductor laser device 310 according to this embodiment, a metal paste similar to the metal paste 60p according to the first embodiment is placed on the spacer 40. Here, the amount of metal paste to be placed is appropriately adjusted depending on the position in the resonance direction. For example, a relatively large amount of metal paste is placed near the center of the resonance direction on the spacer 40, and a relatively small amount of metal paste is placed near both ends of the spacer 40 in the resonance direction. By the manufacturing method of the semiconductor laser device 310 according to this embodiment, which includes such a paste placement step, it is possible to manufacture the semiconductor laser device 310 as shown in FIG. 18 .

[0099] The method for manufacturing the semiconductor laser device 310 as described above provides the same effects as those of the semiconductor laser device 310 described above.

[0100] Fifth Embodiment A semiconductor laser device according to a fifth embodiment and a manufacturing method thereof will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 10 according to the first embodiment in the configurations of the spacer and the bonding member. The semiconductor laser device according to this embodiment will be described below with reference to FIGS. 19 and 20, focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIGS. 19 and 20 are a schematic plan view and a cross-sectional view, respectively, showing the configuration of a semiconductor laser device 410 according to this embodiment. FIG. 19 shows a plan view of the semiconductor laser device 410 in a plan view of the mounting surface 80a of the submount 80. FIG. 19 shows a plan view of the semiconductor laser device 410 with the semiconductor laser element 20 removed to explain the configurations of the spacer 440 and the bonding member 460, with only the outline of the semiconductor laser element 20 indicated by a dashed line. FIG. 20 shows a cross section of the semiconductor laser device 410 taken along line XX-XX in FIG. 19.

[0101] As shown in FIGS. 19 and 20, a semiconductor laser device 410 according to this embodiment includes a submount 80 , a spacer 440 , a semiconductor laser element 20 , and a bonding member 460 .

[0102] The spacer 440 according to this embodiment includes a first spacer 441 and a second spacer 442 spaced apart from the first spacer 441. The first spacer 441 and the second spacer 442 are arranged in a first direction. Each of the first spacer 441 and the second spacer 442 is a plate-like member having a constant thickness (dimension in the Z-axis direction) extending in the resonance direction of the laser light L0. As shown in FIG. 20 , the first spacer 441 is disposed in a position facing the first non-implantation region 31 of the semiconductor laser element 20, and the second spacer 442 is disposed in a position facing the second non-implantation region 32 of the semiconductor laser element 20. The implantation region 30a of the semiconductor laser element 20 is disposed in a position facing the region between the first spacer 441 and the second spacer 442. In other words, the spacer 440 is not disposed between the implantation region 30a and the mounting surface 80a. That is, the ridge 25R is disposed in a position facing the region between the first spacer 441 and the second spacer 442.

[0103] The first spacer 441 has an upper surface 441u facing the first non-implantation region 31 and a side surface 441s located at one end in the first direction farther from the second spacer 442. The second spacer 442 has an upper surface 442u facing the second non-implantation region 32 and a side surface 442s located at one end in the first direction farther from the first spacer 441.

[0104] The bonding member 460 according to this embodiment is disposed between the spacer 440 and the semiconductor laser element 20, and between the mounting surface 80a and the semiconductor laser element 20. The bonding member 460 is disposed between the first spacer 441 and the second spacer 442, and is bonded to the injection region 30a and the mounting surface 80a. The bonding member 460 is also disposed continuously in the region between the first spacer 441 and the second spacer 442, the upper surface 441u of the first spacer 441, the side surface 441s of the first spacer 441, and the mounting surface 80a adjacent to the side surface 441s. The bonding member 460 is also disposed continuously in the region between the first spacer 441 and the second spacer 442, the upper surface 442u of the second spacer 442, the side surface 442s of the second spacer 442, and the mounting surface 80a adjacent to the side surface 442s.

[0105] In the semiconductor laser device 410 according to this embodiment, the facing surface 20a is also exposed from the bonding member 460 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, since the bonding member 460 is not disposed at one and the other ends in the first direction of the facing surface 20a of the semiconductor laser element 20, adhesion of the bonding member 460 to the side surfaces 20sa, 20sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0106] Furthermore, in this embodiment, by using the first spacer 441 and the second spacer 442 facing the first non-implantation region 31 and the second non-implantation region 32, respectively, the inclination of the semiconductor laser element 20 with respect to the submount 80 can be reduced.

[0107] Furthermore, in this embodiment, the spacer 440 is not disposed between the implantation region 30a and the mounting surface 80a, so that the load on the implantation region 30a can be reduced.

[0108] A method for manufacturing a semiconductor laser device 410 according to this embodiment will be described. The method for manufacturing a semiconductor laser device 410 according to this embodiment differs from the method for manufacturing a semiconductor laser device 10 according to embodiment 1 mainly in the paste placement step. The paste placement step according to this embodiment will be described below with reference to FIGS. 21 and 22. FIGS. 21 and 22 are schematic cross-sectional views showing a first example and a second example of the paste placement step in the method for manufacturing a semiconductor laser device 410 according to this embodiment, respectively. FIGS. 21 and 22 show cross sections of a submount 80, a spacer 40, and a metal paste 60p at the same positions as in FIG. 20.

[0109] As shown in Figure 21, in the paste placement process of the manufacturing method of the semiconductor laser device 410 of this embodiment, a metal paste 460p similar to the metal paste 60p of embodiment 1 is continuously placed between the first spacer 441 and the second spacer 442, on the upper surface 441u of the first spacer 441, the side surface 441s of the first spacer 441, the mounting surface 80a adjacent to the side surface 441s, the upper surface 442u of the second spacer 442, the side surface 442s of the second spacer 442, and the mounting surface 80a adjacent to the side surface 442s.

[0110] 22 , the metal paste 460p may be continuously disposed between the first spacer 441 and the second spacer 442, on the upper surface 441u of the first spacer 441, and on the upper surface 442u of the second spacer 442, and may not be disposed on the side surface 441s of the first spacer, the mounting surface 80a adjacent to the side surface 441s, or the side surface 442s of the second spacer 442, or the mounting surface 80a adjacent to the side surface 442s. Even when such a paste disposing step is adopted, the metal paste 460p can be pushed out onto the side surface 441s of the first spacer 441, the mounting surface 80a adjacent to the side surface 441s, the side surface 442s of the second spacer 442, and the mounting surface 80a adjacent to the side surface 442s in the pressing step.

[0111] The method for manufacturing the semiconductor laser device 410 according to this embodiment, which includes the paste placement step, allows manufacturing the semiconductor laser device 410. The method for manufacturing the semiconductor laser device 410 as described above provides the same effects as those of the semiconductor laser device 410 described above.

[0112] Sixth Embodiment A semiconductor laser device according to the sixth embodiment will be described. The semiconductor laser device according to the sixth embodiment differs from the semiconductor laser device 10 according to the first embodiment mainly in the configuration of the spacer. The semiconductor laser device according to the sixth embodiment will be described below with reference to FIG. 23, focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIG. 23 is a schematic cross-sectional view showing the configuration of a semiconductor laser device 510 according to the sixth embodiment. FIG. 23 shows a cross-section of the semiconductor laser device 510 at the same position as the cross-section shown in FIG.

[0113] As shown in FIG. 23, a semiconductor laser device 510 according to this embodiment includes a submount 80, a spacer 540, a semiconductor laser element 20, and a bonding member 60.

[0114] The width of spacer 540 in the first direction increases toward mounting surface 80a. In other words, side surfaces 540sa and 540sb located at the ends of spacer 540 in the first direction are inclined with respect to the normal to mounting surface 80a. In the example shown in FIG. 23 , the cross section of spacer 540 perpendicular to the resonance direction has a trapezoidal shape.

[0115] In the semiconductor laser device 510 according to this embodiment, the facing surface 20 a is also exposed from the bonding member 60 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, since the bonding member 60 is not disposed at one and the other ends in the first direction of the facing surface 20 a of the semiconductor laser element 20, adhesion of the bonding member 60 to the side surfaces 20 sa, 20 sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0116] Furthermore, in the semiconductor laser device 510 according to this embodiment, the width of the spacer 540 in the first direction increases toward the mounting surface 80a, so that when heat generated in the semiconductor laser element 20 is conducted to the upper surface 540u of the spacer 540, the heat can be diffused in the first direction when conducted from the upper surface 540u to the mounting surface 80a. Therefore, according to the semiconductor laser device 510 according to this embodiment, the heat dissipation characteristics of the spacer 540 can be improved.

[0117] Seventh Embodiment A semiconductor laser device according to a seventh embodiment and a manufacturing method thereof will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 10 according to the first embodiment mainly in the configuration of the spacer and the submount. The semiconductor laser device according to this embodiment will be described below with reference to FIG. 24, focusing on the differences from the semiconductor laser device 10 according to the first embodiment. FIG. 24 is a schematic cross-sectional view showing the configuration of a semiconductor laser device 610 according to this embodiment. FIG. 24 shows a cross-section of the semiconductor laser device 610 at the same position as the cross-section shown in FIG.

[0118] As shown in FIG. 24, a semiconductor laser device 610 according to this embodiment includes a submount 680 , a spacer 640 , a semiconductor laser element 20 , and a bonding member 60 .

[0119] The semiconductor laser device 610 according to this embodiment has a structure 610S, which has a submount 680 and a spacer 640. In this embodiment, the submount 680 and the spacer 640 are integrally formed as the structure 610S.

[0120] Structure 610S has a substrate 681 and a pad electrode 682. Substrate 681 has a plate-shaped portion 681b and a protrusion 681p arranged on its main surface. Protrusion 681p has a rectangular parallelepiped shape similar to that of spacer 40 according to embodiment 1. Substrate 681 can be formed, for example, by cutting a plate-shaped base material having a thickness (i.e., dimension in the Z-axis direction) similar to that of structure 610S.

[0121] The pad electrode 682 is an electrode disposed on the surface of the substrate 681 facing the semiconductor laser element 20. In this embodiment, the pad electrode 682 is a conductive film similar to the pad electrode 82 according to the first embodiment.

[0122] The submount 680 has a mounting surface 680a facing the semiconductor laser element 20. In this embodiment, the mounting surface 680a is the upper surface of the portion of the pad electrode 682 that is placed on the plate-like portion 681b (i.e., the surface facing the semiconductor laser element 20). Of the structure 610S, the portion closer to the semiconductor laser element 20 than the plane including the mounting surface 680a is the spacer 640, and the remaining portion is the submount 680.

[0123] In the semiconductor laser device 610 according to this embodiment, the facing surface 20 a is also exposed from the bonding member 60 at one and the other ends in the first direction of the semiconductor laser element 20. In this way, the bonding member 60 is not disposed at one and the other ends in the first direction of the facing surface 20 a of the semiconductor laser element 20, so that adhesion of the bonding member 60 to the side surfaces 20 sa, 20 sb can be reduced. Therefore, current leakage in the semiconductor laser element 20 can be reduced.

[0124] In addition, in this embodiment, the submount 680 and the spacer 640 are integrally formed. This simplifies the configuration of the semiconductor laser device 610. It also reduces misalignment between the submount 680 and the spacer 640. Furthermore, it is possible to reduce the thermal resistance between the spacer 640 and the submount 680, thereby improving the heat dissipation characteristics.

[0125] A method for manufacturing the semiconductor laser device 610 according to this embodiment will be described. The method for manufacturing the semiconductor laser device 610 according to this embodiment differs from the method for manufacturing the semiconductor laser device 10 according to the first embodiment in the submount preparation step and the spacer arrangement step.

[0126] In this embodiment, the submount preparation step and the spacer placement step are performed simultaneously. In this embodiment, first, a substrate 681 is prepared. Specifically, for example, a plate-shaped base material is cut to form the substrate 681 having a plate-shaped portion 681b and a protruding portion 681p placed on its main surface. Next, a pad electrode 682 is formed on the substrate 681. Specifically, the pad electrode 682 is formed on the main surface of the substrate 681 having the protruding portion 681p. This allows the submount 680 to be prepared, and the spacer 640 to be placed on the mounting surface 680a of the submount 680.

[0127] The method for manufacturing the semiconductor laser device 610 according to this embodiment, which includes the submount preparation step and the spacer arrangement step, as described above, allows manufacturing the semiconductor laser device 610. The method for manufacturing the semiconductor laser device 610 as described above provides the same effects as those of the semiconductor laser device 610 described above.

[0128] (Other Modifications) Although the semiconductor laser device and the manufacturing method thereof according to the present disclosure have been described above based on the embodiments, the present disclosure is not limited to the above-described embodiments.

[0129] For example, in the above-described first to fifth and seventh embodiments, the spacer has a rectangular parallelepiped shape, but the shape of the spacer is not limited to this. For example, the spacer may have an oval shape or the like when viewed from above on the mounting surface 80a.

[0130] Furthermore, in each of the above-described embodiments, the semiconductor laser element 20 protrudes from the end of the submount 80 in a planar view of the mounting surface 80 a of the submount 80, but the semiconductor laser element 20 does not have to protrude from the end of the submount 80.

[0131] Furthermore, although the semiconductor laser element 20 according to each of the above embodiments has the protrusion 25P and the protrusions 31p and 32p, the semiconductor laser element 20 does not have to have the protrusion 25P and the protrusions 31p and 32p. The first non-implantation region and the second non-implantation region may be flat regions, and the implantation region 30a may protrude from the first non-implantation region and the second non-implantation region toward the submount 80.

[0132] Furthermore, in the method for manufacturing the semiconductor laser device 10 according to the first embodiment, in the paste disposing step, the metal paste 60p is disposed only on the spacer 40 above the mounting surface 80a, but the paste disposing step is not limited to this. For example, in the paste disposing step, the metal paste 60p may be disposed continuously on the spacer 40 and the mounting surface 80a, similar to the paste disposing step in the method for manufacturing the semiconductor laser device 10 according to the second embodiment.

[0133] In addition, this disclosure also includes forms obtained by applying various modifications that a person skilled in the art would conceive of to each embodiment and variant, and forms realized by arbitrarily combining the components and functions of each embodiment and variant within the scope that does not deviate from the intent of this disclosure.

[0134] For example, the spacers and submounts according to the fifth and sixth embodiments may be integrally formed, like the spacer 640 and submount 680 according to the seventh embodiment.

[0135] The semiconductor laser device and manufacturing method thereof according to the present disclosure are useful as light sources and manufacturing methods for products in various fields, such as image display devices such as projectors, automotive parts such as in-vehicle headlamps, lighting fixtures such as spotlights, thermally assisted hard disk drives, or industrial equipment such as laser processing devices.

[0136] 10, 110, 210, 310, 410, 510, 610 Semiconductor laser device 20 Semiconductor laser element 20a Opposing surface 20F Front end face 20R Rear end face 20S Semiconductor laminate 20sa, 20sb, 40sa, 40sb, 441s, 442s, 540sa, 540sb Side face 21 First electrode 21a, 27b Adhesion layer 21b, 27c, 82, 682 Pad electrode 22, 81, 681 Substrate 23 First semiconductor layer 24 Active layer 25 Second semiconductor layer 25P, 31p, 32p, 681p Protrusion 25R Ridge 26 Insulating film 26a Opening 27 Second electrode 27a Contact electrode 30 Electrode surface 30a Injection region 31 First non-injection region 31b, 32b Non-protruding portion 32 Second non-injection region 40, 440, 540, 640 Spacer 40u, 441u, 442u, 540u Upper surface 60, 160, 260, 360, 460 Bonding member 60p, 160p, 460p Metal paste 60r, 160r, 260r Bonding region 80, 680 Submount 80a, 680a Mounting surface 360sa, 360sb Edge 441 First spacer 442 Second spacer 610S Structure 681b Plate-shaped portion L0 Laser light

Claims

1. A semiconductor laser device that emits laser light, comprising: a submount having a mounting surface; a spacer arranged on the mounting surface; an edge-emitting semiconductor laser element arranged above the spacer; and a bonding member made of a porous metal material arranged between the spacer and the semiconductor laser element and bonding the spacer to the semiconductor laser element, wherein the semiconductor laser element has front and rear end faces that form a resonator for the laser light, an opposing surface that faces the submount, a substrate, and a semiconductor laminate arranged between the substrate and the opposing surface, wherein, in a plan view of the mounting surface, the spacer is not present outside one end of the semiconductor laser element in a first direction perpendicular to the resonance direction of the laser light, and, in a plan view of the mounting surface, the bonding member is arranged between the one end of the semiconductor laser element and one end of the spacer in the first direction, and at the one end of the semiconductor laser element, the opposing surface is exposed from the bonding member.

2. The semiconductor laser device according to claim 1, wherein the opposing surface has an injection region extending in the resonance direction of the laser light, the injection region faces a region of the semiconductor laminate into which current is injected from the opposing surface, the bonding member is disposed between the injection region and the mounting surface, and the one end of the spacer is disposed between the one end of the semiconductor laser element and the injection region in a plan view of the mounting surface.

3. The semiconductor laser device according to claim 1 or 2, wherein, in a plan view of the mounting surface, the spacer is not present outside the other end of the semiconductor laser element in the first direction.

4. The semiconductor laser device according to any one of claims 1 to 3, wherein the bonding member is disposed in a region of the mounting surface that is located between the one end of the semiconductor laser element and the one end of the spacer in a plan view of the mounting surface.

5. A semiconductor laser device according to any one of claims 1 to 4, wherein the joining member is continuously arranged in a region of the mounting surface adjacent to the one end of the spacer, a side surface located at the one end of the spacer, between the spacer and the semiconductor laser element, a side surface located at the other end of the spacer in the first direction, and a region of the mounting surface adjacent to the other end of the spacer.

6. The semiconductor laser device according to any one of claims 1 to 5, wherein the distance between said one end of said spacer and said semiconductor laser element is smaller than the thickness of said spacer.

7. The semiconductor laser device according to any one of claims 1 to 6, wherein the bonding member is not present outside the one end of the semiconductor laser element in a plan view of the mounting surface.

8. The semiconductor laser device according to any one of claims 1 to 6, wherein, in a plan view of the mounting surface, the joining member protrudes outward beyond the one end of the semiconductor laser element.

9. The semiconductor laser device according to claim 8, wherein the thickness of the joining member located between the one end of the semiconductor laser element and the mounting surface is smaller than the thickness of the spacer.

10. The semiconductor laser device according to claim 8, wherein the thickness of the joining member located between the one end of the semiconductor laser element and the mounting surface is greater than the distance between the one end of the spacer and the semiconductor laser element.

11. The semiconductor laser device according to claim 1, wherein the joining member is disposed on a side surface located at one end of the spacer, and an end of the side surface close to the mounting surface is exposed from the joining member.

12. A semiconductor laser device according to any one of claims 1 to 11, wherein the opposing surface has an injection region extending in the resonance direction of the laser light, the injection region faces a region of the semiconductor laminate into which a current is injected from the opposing surface, and the spacer is disposed between the injection region and the mounting surface.

13. A semiconductor laser device according to any one of claims 1 to 11, wherein the opposing surface has an injection region extending in the resonance direction of the laser light, the injection region faces a region of the semiconductor laminate into which a current is injected from the opposing surface, and the spacer is not disposed between the injection region and the mounting surface.

14. The semiconductor laser device according to claim 13, wherein the spacer comprises a first spacer and a second spacer spaced apart from the first spacer, and the implantation region is disposed at a position facing a region between the first spacer and the second spacer.

15. The semiconductor laser device according to any one of claims 1 to 14, wherein the joining member is a sintered body of particles made of at least one material selected from the group consisting of Au, Ag, and Cu.

16. The semiconductor laser device according to any one of claims 1 to 15, wherein the thermal conductivity of the spacer is 50 W / (m·K) or more.

17. The semiconductor laser device according to any one of claims 1 to 16, wherein the thermal conductivity of the spacer is greater than the thermal conductivity of the joining member.

18. A method for manufacturing a semiconductor laser device that emits laser light, the semiconductor laser device comprising: a submount having a mounting surface; a spacer; an edge-emitting semiconductor laser element; and a bonding member made of a porous metal material that is arranged between the spacer and the semiconductor laser element and bonds the spacer to the semiconductor laser element, the semiconductor laser element having front and rear end faces that form a resonator for the laser light, an opposing surface that faces the mounting surface, a substrate, and a semiconductor laminate arranged between the substrate and the opposing surface, the spacer is not present outside one end of the semiconductor laser element in a first direction perpendicular to the resonance direction of the laser light in a plan view of the mounting surface, the bonding member is arranged between the one end of the semiconductor laser element and the spacer in a plan view of the mounting surface, and the opposing surface at the one end of the semiconductor laser element is exposed from the bonding member, the method for manufacturing the semiconductor laser device comprising: a spacer arrangement step of arranging the spacer on the mounting surface; and a paste arrangement step of arranging a metal paste containing metal particles on the spacer. a pressing step of pressing the opposing surface of the semiconductor laser element against the metal paste while the opposing surface is facing the metal paste; and a heating step of heating the metal paste to form the joining member.

19. A method for manufacturing a semiconductor laser device as described in claim 18, wherein in the paste placement step, the metal paste is placed only on the spacer above the mounting surface, and in the pressing step, the metal paste is placed between the one end of the semiconductor laser element and the spacer in a planar view of the mounting surface.

20. The method for manufacturing a semiconductor laser device according to claim 18, wherein in the paste applying step, the metal paste is applied continuously on the spacer and on the mounting surface.

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