Semiconductor laser element

Abstract

To provide a semiconductor laser element having high power conversion efficiency.SOLUTION: A semiconductor laser element according to an embodiment of the present disclosure includes a semiconductor layered portion including an active layer and having a waveguide structure. The semiconductor layered portion includes (i) a first region including a diffraction grating, and (ii) a second region including a core region and cladding regions located on both sides of the core region, the second region allowing laser light to propagate in a plurality of transverse modes. A width of the first region is greater than a width of the core region in a direction in which the core region and the cladding regions are arranged. A current shielding structure is located at a position overlapping the first region in a top view, and the current shielding structure includes one or more opening regions for injecting a current into the semiconductor layered portion in the first region. A total area of the one or more opening regions is smaller than an area of the first region in the top view.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a semiconductor laser device.

Background Art

[0002] In recent years, higher output of laser light from semiconductor laser devices has been demanded. High-output semiconductor laser devices have come to be used, for example, as light sources for processing. For example, Patent Document 1 discloses a multi-transverse-mode laser that can prevent optical damage on the stripe side.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the semiconductor laser device disclosed in Patent Document 1 has insufficient power conversion efficiency and room for improvement.

[0005] Therefore, an object of the present disclosure is to provide a semiconductor laser device with high power conversion efficiency.

Means for Solving the Problems

[0006] A semiconductor laser device according to an embodiment of the present disclosure is a semiconductor laser device including an active layer and having a semiconductor stacked portion having a waveguide structure, wherein the semiconductor stacked portion (i) includes a first region containing a diffraction grating, and (ii) includes a second region having a core region and clad regions provided on both sides of the core region and propagating laser light in a plurality of transverse modes, and In the direction in which the core region and the cladding region are arranged, the width of the first region is wider than the width of the core region. In a top view, a current shielding structure is provided at a position overlapping the first region. The current shielding structure has one or more opening regions for injecting current into the semiconductor stack in the first region. In a top view, the total area of the one or more opening regions is smaller than the area of the first region.

Advantages of the Invention

[0007] According to one embodiment of the present disclosure, a semiconductor laser device with high power conversion efficiency can be provided.

Brief Description of the Drawings

[0008]

Figure 1

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Figure 10

Embodiments for Carrying Out the Invention

[0009] Hereinafter, with reference to the drawings, a semiconductor laser element of the present disclosure, embodiments for implementing the semiconductor laser element of the present disclosure, and modified examples will be described. Note that the semiconductor laser element according to the present disclosure described below is for embodying the technical idea of the present disclosure, and unless otherwise specified, the present disclosure is not limited to the following. In each drawing, members having the same function may be denoted by the same reference numerals. For the sake of explanation or ease of understanding of the gist, it may be shown separately as embodiments, modified examples, or examples for convenience, but partial substitution or combination of the configurations shown in different embodiments, modified examples, and examples is possible. In the embodiments, modified examples, and examples described below, descriptions of matters common to the foregoing will be omitted, and only different points will be described. In particular, the same operational effects due to the same configuration will not be sequentially mentioned for each of the embodiments, modified examples, and examples. The sizes and positional relationships of the members shown in each drawing may be exaggerated for clarity of explanation.

[0010] Semiconductor Laser Element of the Present Disclosure The semiconductor laser element of the present disclosure is a semiconductor laser element including an active layer 120 and including a semiconductor laminate portion 101 having a waveguide structure shown in FIG. 2. Specifically, as shown in FIGS. 3 to 4 and the like, the semiconductor laminate portion 101 in the semiconductor laser element of the present disclosure (i) a first region 1 including a diffraction grating 105, and (ii) a second region 2 having a core region 21 and clad regions 22 provided on both sides of the core region 21 and propagating laser light in a plurality of transverse modes. Also, in the direction in which the core region 21 and the clad region 22 are arranged, the width of the first region 1 is wider than the width of the core region 21. Further, in a top view, a current shielding structure 10 is provided at a position overlapping the first region 1, and the current shielding structure 10 has one or more opening regions 140a for injecting current into the semiconductor layer portion in the first region 1. Further, the refractive index of the first region 1 is n1, the refractive index of the core region 21 is n 21 and the refractive index of the clad region 22 is n 22 . In the semiconductor laser element L1 including the first region 1 and the second region 2 configured as described above, the laser light emitted from the second region 2 has a refractive index n1 and a refractive index n 21 and a refractive index n 22 and is propagated through the first region 1 at a maximum divergence angle Θ max1 determined thereby. The laser light emitted from the second region 2 is propagated through the first region 1 at a maximum divergence angle Θ 21 determined by the refractive index n1, the refractive index n 22 and the refractive index n max1 . By doing so, the laser light can be efficiently reflected by the diffraction grating 105 provided in the first region 1. And, in the semiconductor laser element of the present disclosure, in a top view, the total area of the one or more opening regions 140a is smaller than the area of the first region 1. By making the total area of the one or more opening regions 140a smaller than the area of the first region 1, the semiconductor laser element of the present disclosure can reduce the current density injected into the first region 1 and suppress the amount of heat generation in the first region 1 compared to the case where the total area of the one or more opening regions 140a is not made smaller than the area of the first region 1. Here, in this specification, the refractive index n 21 and the refractive index n 22 refer to the effective refractive index considering the optical confinement in the stacking direction of the semiconductor layer portion. The refractive index n1 refers to the effective refractive index considering the optical confinement in the stacking direction of the semiconductor layer portion and further averaging the modulation of the refractive index of the diffraction grating. Also, the maximum divergence angle Θ max1 is equal to the maximum light receiving angle of the optical waveguide of the second region 2. Further, for example, the semiconductor laser element is a transverse multimode type semiconductor laser element. By being a transverse multimode type semiconductor laser element, compared with a transverse single mode type semiconductor laser element, it is possible to further obtain the effect of improving the luminous efficiency by reducing the heat generation due to the idle current in the portion that does not contribute to oscillation (light propagation).

[0011] Since the semiconductor laser element of the present disclosure configured as described above can reduce the amount of heat generation in the first region 1, it is possible to increase the luminous output with respect to the power consumption and efficiently obtain high-power light. Hereinafter, the reason will be described more specifically. First, a semiconductor laser element including a diffraction grating 105 in the first region 1 and having a waveguide structure in the second region 2 oscillates laser according to, for example, the following principle. For example, light emitted by injecting current into the core region 21 of the second region 2 propagates through a waveguide including the core region 21 and enters the first region 1, and is reflected by the diffraction grating 105 provided in the first region 1 and returns to the second region 2. By repeating the amplification of the light that has returned to the second region 2, the semiconductor laser element oscillates laser. In addition, in order to more effectively oscillate laser, the semiconductor laser element L1 of the present disclosure may be coated on either one or both of the end face of the first region 1 opposite to the second region 2 and the end face of the second region 2 opposite to the first region 1. The semiconductor laser element may include an antireflection coating (AR coating) provided on the end face of the first region 1 opposite to the second region 2 and a high reflection coating (HR coating) provided on the end face of the second region 2 opposite to the first region 1. Here, the inventors have obtained the finding that when current injection is performed throughout the first region 1, the overall power conversion efficiency decreases due to the entire first region 1 generating heat. Since the second region 2 is a region that amplifies the light returned from the first region 1 and causes laser oscillation, it is necessary to inject a current equal to or greater than a certain level. In contrast, the main function of the first region 1 is to reflect the light incident from the second region 2 with the diffraction grating 105 and return it to the second region 2. Therefore, the current injected into the first region 1 can be made less than the current injected into the second region 2. For this reason, by making the total area of the one or more opening regions 140a for injecting current in the first region 1 smaller than the area of the first region 1, the amount of heat generation in the first region 1 can be suppressed and the power conversion efficiency can be increased.

[0012] Embodiment 1 Hereinafter, the semiconductor laser element L1 according to Embodiment 1 will be described with reference to FIGS. 1 to 4. The semiconductor laser element L1 according to Embodiment 1 is a semiconductor laser element of the present disclosure, The current blocking structure 10 is constituted by an insulating film 140 provided on the semiconductor stack portion 101. By forming the current blocking structure 10 with the insulating film 140, it becomes easy to provide the current blocking structure 10 at a predetermined position on the semiconductor stack portion 101. Specifically, as will be described later, in the insulating film 140 provided on the semiconductor stack portion 101 in the first region 1, one or more opening regions 140a are provided, and the amount of current injected into the semiconductor stack portion 101 in the first region 1 is suppressed by the opening regions 140a. Here, the opening region 140a is, for example, circular. By making the opening region 140a circular, the amount of current flowing through the opening region 140a can be made uniform. Hereinafter, the semiconductor laser element L1 of Embodiment 1 will be described in detail with reference to the drawings.

[0013] Here, FIG. 1 is a top view of the semiconductor laser element L1 according to Embodiment 1. FIG. 2 is a top view schematically showing the region structure of the semiconductor laser element L1 according to Embodiment 1. FIG. 3 is a schematic cross-sectional view taken along line III-III of the semiconductor laser element shown in FIG. 1. FIG. 4 is a schematic cross-sectional view taken along line IV-IV of the semiconductor laser element L1 shown in FIG. 1.

[0014] The semiconductor laser element L1 according to Embodiment 1 includes a semiconductor laminate portion 101 provided on a substrate 100. As shown in FIGS. 3 to 4, for example, the semiconductor laminate portion 101 (a) an n-side semiconductor layer 110 including an n-side clad layer 111 and an n-side optical guide layer 112, (b) an active layer 120 provided on the n-side semiconductor layer 110, (c) a p-side semiconductor layer 130 provided on the active layer 120 and including a p-side optical guide layer 131, a p-side clad layer 132, and a p-side contact layer 133, and includes. Further, the semiconductor laminate portion 101 includes, for example, a ridge 135 provided on the p-side contact layer 133 and the p-side clad layer 132. The ridge 135 includes a first ridge 135a provided in the first region 1 and a second ridge 135b provided in the second region 2. In a top view, the first ridge 135a and the second ridge 135b are provided so that their center lines coincide with each other, for example, in the traveling direction of the laser light. In FIG. 1, the outer surfaces of the first ridge 135a and the second ridge 135b are drawn to coincide with the outer surface of the second electrode 152 described later. Therefore, in FIG. 1, the first ridge 135a and the second ridge 135b are shown by broken lines drawn from the outer surfaces of the first ridge 135a and the second ridge 135b. Also, as described above, since the light emitted from the second region 2 and incident on the first region 1 spreads and propagates in the first region 1, the width of the first ridge 135a is set wider than the width of the second ridge 135b. Furthermore, the outer surface of the first region 1 and the outer surface of the first ridge 135a are close to each other, and the refractive index n1 of the first region 1 is constant without change in the light propagation direction and the width direction. Here, in this specification, the width direction refers to a direction orthogonal to both the light propagation direction and the lamination direction of the semiconductor laminate portion 101.

[0015] On the semiconductor layer portion 101, a p - electrode 150 is provided in contact with the upper surface of the ridge 135. The p - electrode 150 includes a first electrode 151 and a second electrode 152, and the first electrode 151 is provided in contact with the p - side contact layer 133. As will be described later, in the first region 1, by connecting the first electrode 151 and the second electrode 152 through the opening region 140a of the insulating film 140, current injection into the first region 1 is suppressed. That is, in Embodiment 1, the insulating film 140 provided in the first region 1 constitutes the current shielding structure 10. Specifically, first, the first electrode 151 is provided, for example, in contact with the entire upper surface of the p - side contact layer 133 on the ridge 135 of the semiconductor layer portion 101. Then, an insulating film 140 is provided on the p - side contact layer 133 via the first electrode 151. The insulating film 140 has one or a plurality of opening regions 140a located on the first ridge 135a and an opening 140b located on the second ridge 135b. The opening region 140a and the opening 140b are, for example, provided separately. In this specification, the terms "opening region" and "opening" do not only refer to a region surrounded by four sides. For example, a region sandwiched between two insulating films can be expressed as an opening region of the insulating film.

[0016] And in Embodiment 1, the second electrode 152 is provided to cover the opening region 140a and the opening 140b, and the second electrode 152 is connected to the first electrode 151 through the opening region 140a and the opening 140b. Here, in Embodiment 1, in the second region 2, since a waveguide structure is formed by narrowing the width of the ridge, it is not necessary to have a current shielding function. As shown in FIG. 4, in the second region 2, the width of the opening 140b is set to be approximately equal to the width of the second ridge 135b. On the other hand, in the first region 1, in order to suppress the amount of injected current, the total area of the one or a plurality of opening regions 140a in top view is made smaller than the area of the first region 1 to constitute the current shielding structure 10. Here, the first electrode 151 is, for example, ITO. As described above, the current injection into the p-side contact layer 133 in the first region 1 of the first embodiment is determined by parameters including the total area of the opening region 140a provided in the insulating film 140, the contact resistance between the first electrode 151 and the second electrode 152, and the like. In other words, in order to effectively reduce heat generation due to ineffective current or the like in the first region 1, the sum of the areas of the opening regions 140a provided in the insulating film 140 and other parameters such as the contact resistance between the first electrode 151 and the second electrode 152 can be appropriately adjusted. For example, the sum of the areas of the opening regions 140a provided in the insulating film 140 is preferably 0.04% or more and 0.22% or less of the area of the first region 1 in a top view. By setting it to 0.04% or more, current can be effectively supplied to the diffraction grating 105, and the diffraction grating 105 can have sufficient light transmittance. Also, by setting it to 0.22% or less, heat generation due to ineffective current or the like in the first region 1 can be effectively reduced. The sum of the areas of the opening regions 140a provided in the insulating film 140 is 13.8μm 2 or more and 207μm 2 or less. Further, for example, the thickness of the first electrode 151 can be 0.5μm or more and 2μm or less. By setting this value, current can be effectively supplied to the diffraction grating 105. Also, the opening regions 140a may be arranged along a straight line. By arranging the opening regions 140a along a straight line, current can be supplied to the diffraction grating 105 evenly.

[0017] In the semiconductor laser element L1 of the first embodiment, the width of the ridge 135 is set as follows so that laser light propagates in a plurality of desired transverse modes. First, the width of the second ridge 135b in the second region 2 is such that the second region 2 has a core region 21 with a refractive index n 21 and cladding regions 22 with a refractive index n 22 provided on both sides of the core region 21. Also, the second ridge 135b is provided at a predetermined interval from both side surfaces of the second region 2 at the center of the p-side semiconductor layer 130 of the second region 2 so that laser light propagates in a desired transverse mode of the folded mode. Thereby, in the second region 2, below the second ridge 135b, the refractive index n21 core region 21 and, on both sides of the core region 21, cladding regions 22 having a refractive index of n 22 are formed, and the waveguide structure of the second region 2 is formed. In the semiconductor laser element L1 of Embodiment 1, the width of the core region 21, that is, the width of the second ridge 135b, is set so that laser light including a plurality of desired lateral modes is propagated. Note that the first electrode 151 is preferably provided so as to be in contact with the upper surface of the second ridge 135b without contacting the upper surfaces of the p-side cladding layers 132 on both sides of the second ridge 135b. With such a configuration, the flow of current through the cladding region 22 can be reduced. Also, in the semiconductor laser element L1 of Embodiment 1, the first electrode 151 provided in contact with the semiconductor stack 101 is provided at a position overlapping with the insulating film 140 constituting the current blocking structure 10 in a top view. With such a configuration, the shape of the first electrode 151 is simplified, and it becomes easy to provide the first electrode 151. Note that in Embodiment 1, by providing the second ridge 135b, a core region was formed in a top view, and cladding regions were formed on both sides of the core region. However, for example, without forming the second ridge 135b, for example, the core region and the cladding region may be formed by making the width of the portion where current is injected in the second region 2 narrower than the overall width of the second region 2.

[0018] On the other hand, the first region 1 is not a region that confines and propagates light that is incident from the second region 2 and spreads and propagates at the maximum divergence angle Θ max1 into a specific waveguide (core region 21). Therefore, the light incident from the second region 2 has the maximum divergence angle Θ max1As long as it can spread and propagate in the first region 1, the first ridge 135a is not an essential configuration in the first region 1. For example, in the semiconductor layer 101, the portion excluding the second region 2 may be used as the first region 1 without forming the first ridge 135a. Further, when the first ridge 135a is included, as shown in FIG. 3, for example, both side surfaces of the first ridge 135a can be provided close to both side surfaces of the first region 1. The width of the semiconductor layer 101 constituting the first region 1 and the width of the first ridge 135a when the first ridge 135a is included are such that the equivalent refractive indices for a plurality of transverse modes of the laser light incident from the second region 2 to the first region 1 are substantially the same, and the maximum divergence angle Θ of the laser light emitted from the second region 2 and incident on the first region 1 max1 is considered so that the propagated light does not leak from the side surface of the semiconductor layer 101. Specifically, for example, in a cross section perpendicular to the optical axis of the laser light, both ends of the first region 1 in the direction perpendicular to the stacking direction of the semiconductor layer 101 are respectively from both ends of the emission end surface of the core region 21 on the first region 1 side by the maximum divergence angle Θ max1 so that they are located outside the virtual lines spreading at. The width of the first region 1 is set accordingly. And a diffraction grating 105 is provided in the first region 1. The diffraction grating 105 is provided such that, for example, both ends of the diffraction grating 105 extend to both ends of the first region 1. Here, as shown in FIGS. 3 and 4, the cross-sectional shape of the ridge 135 may be a rectangle with a constant width, or may be a trapezoidal shape in which the width becomes narrower as it moves away from the substrate 100, or an inverted trapezoidal shape in which the width becomes wider as it moves away from the substrate 100.

[0019] The semiconductor laser element L1 of Embodiment 1 according to the present disclosure configured as described above sets the width of the waveguide in the second region 2 so that laser oscillation including a plurality of desired transverse modes is possible, and in the first region 1, a current blocking structure 10 is provided. Accordingly, according to the semiconductor laser element of Embodiment 1, since laser light can be oscillated and propagated in a plurality of transverse modes, a high output can be achieved, and a semiconductor laser element L1 with high power conversion efficiency can be provided.

[0020] Hereinafter, each component of the semiconductor laser element L1 of Embodiment 1 will be described in detail with specific examples. Note that the semiconductor laser element L1 of Embodiment 1 is not limited to the following specific examples as long as it has a basic configuration capable of obtaining the above effects.

[0021] (Substrate 100) The substrate 100 of the semiconductor laser element L1 of Embodiment 1 is, for example, a semiconductor substrate. The substrate 100 is, for example, a nitride semiconductor substrate such as a GaN substrate. The nitride semiconductor substrate may contain an n-type impurity. The element serving as the n-type impurity may be, for example, O, Si, or Ge. Using the nitride semiconductor substrate, the upper surface thereof can be made the +c plane (i.e., the (0001) plane). In Embodiment 1, the c plane is not limited to the plane that exactly coincides with the (0001) plane, and also includes a plane having an off-angle of ±1 degree or less, preferably ±0.03 degree or less. The semiconductor laser element L1 may not have the substrate 100. As the upper surface of the substrate 100, an m plane, an a plane, an r plane, or the like may be used.

[0022] (Semiconductor stack 101) As described above, the semiconductor stack 101 may include, for example, an n-side semiconductor layer 110 including an n-side cladding layer 111 and an n-side optical guide layer 112, an active layer 120 provided on the n-side semiconductor layer 110, and a p-side semiconductor layer 130 provided on the active layer 120 and including a p-side optical guide layer 131, a p-side cladding layer 132, and a p-side contact layer 133. The semiconductor layers of the semiconductor stack 101 are, for example, III-V semiconductor layers. Examples of the III-V semiconductor layers include nitride semiconductor layers formed with a composition of In α Al β Ga 1-α-β N, (0≤α, 0≤β, α + β≤1). Examples of the element serving as the n-type impurity used in the nitride semiconductor layer include Si or Ge. Examples of the element serving as the p-type impurity include Mg. Thereby, nitride semiconductor layers of each conductivity type can be formed.

[0023] (n-side semiconductor layer 110) The n-side semiconductor layer 110 has one or more semiconductor layers containing n-type impurities. The n-side semiconductor layer 110 has, for example, a refractive index of n 111 of the n-side cladding layer 111 and a refractive index of n 112 of the n-side optical guide layer 112. The n-side semiconductor layer 110 may further have an undoped layer that is not intentionally doped with impurities. Refractive index n 111 and refractive index n 112 are smaller than the refractive index n 120 of the active layer 120. The refractive index n 111 and refractive index n 112 are different from each other. For example, the refractive index n 111 is smaller than the refractive index n 112 .

[0024] The n-side cladding layer 111 is disposed between the active layer 120 and the substrate 100. The n-side cladding layer 111 may be, for example, a nitride semiconductor layer. The nitride semiconductor includes, for example, AlGaN or GaN. The film thickness of the n-side cladding layer 111 may be, for example, 0.45 μm or more and 3.0 μm or less. The content of the n-type impurity may be, for example, 1×10 17 cm -3 or more and 5×10 18 cm -3 or less.

[0025] The n-side optical guide layer 112 is disposed between the active layer 120 and the n-side cladding layer 111. The n-side optical guide layer 112 may be, for example, a nitride semiconductor layer. The nitride semiconductor includes, for example, AlGaN, GaN, or InGaN. The film thickness of the n-side optical guide layer 112 may be, for example, 0.05 μm or more and 0.5 μm or less. The content of the n-type impurity may be, for example, 1×10 17 cm -3 or more and 5×10 18 cm -3 or less.

[0026] (Active layer 120) An active layer 120 is formed on the n-side light guide layer 112. The active layer 120 emits light, for example, with a wavelength of 360 nm or more and 800 nm or less. The active layer 120 may have a quantum well structure composed of one or more well layers and a plurality of barrier layers. The well layer and the barrier layer are, for example, GaN, InGaN, AlGaN, or AlInGaN. The well layer is, for example, AlGaN, GaN, or InGaN, and is a nitride semiconductor having a smaller bandgap energy than the barrier layer. The active layer 120 may be a multiple quantum well structure or a single quantum well structure. Note that either one or both of the well layer and the barrier layer may contain impurities.

[0027] (p-side semiconductor layer 130) The p-side semiconductor layer 130 has one or more semiconductor layers containing p-type impurities. The p-side semiconductor layer 130 is formed on the active layer 120. The p-side semiconductor layer 130 includes, for example, in order from the substrate 100 side (that is, from the active layer 120 side), a p-side light guide layer 131 having a refractive index of refractive index n 131 , a p-side cladding layer 132 having a refractive index of refractive index n 132 , and a p-side contact layer 133 having a refractive index of refractive index n 133 . The p-side semiconductor layer 130 may include other layers. The p-side semiconductor layer 130 may have an undoped layer that is not intentionally doped with impurities. Refractive index n 131 , refractive index n 132 , and refractive index n 133 are smaller than the refractive index n 120 of the active layer 120. The refractive index n 131 , refractive index n 132 , and refractive index n 133 may be different from each other. For example, the refractive index n 131 is larger than the refractive index n 132 .

[0028] The p-side optical guide layer 131 may be, for example, a nitride semiconductor layer. Examples of the nitride semiconductor include AlGaN or GaN. The film thickness of the p-side optical guide layer 131 may be, for example, 0.05 μm or more and 0.25 μm or less. Further, the p-side optical guide layer 131 may be an undoped layer, and for example, 1×10 16 cm -3 or more and 1×10 18 cm -3 or less may contain a p-type impurity.

[0029] The p-side cladding layer 132 may be, for example, a nitride semiconductor layer. Examples of the nitride semiconductor include AlGaN or GaN. It may have a single-layer structure or a multilayer structure in which nitride semiconductor layers having different compositions are stacked on each other. The content of the p-type impurity may be, for example, 1×10 17 cm -3 or more and 1×10 20 cm -3 or less. Note that the p-side cladding layer 132 may not be provided. When the p-side cladding layer 132 is not provided, the amount of the p-type impurity in the semiconductor stacked portion 101 is reduced, and the light loss in the semiconductor stacked portion 101 can be reduced.

[0030] The p-side contact layer 133 may be, for example, a nitride semiconductor. Examples of the nitride semiconductor include AlGaN and GaN. It may have a single-layer structure or a multilayer structure in which nitride semiconductor layers having different compositions are stacked on each other. The content of the p-type impurity may be 1×10 19 cm -3 or more and 1×10 22 cm -3 or less.

[0031] (Waveguide structure) Hereinafter, the waveguide structure of the semiconductor laser element L1 of Embodiment 1 will be described in detail. Here, first, the waveguide structure of the second region 2 will be described, and then the waveguide structure of the first region 1 will be described. The waveguide structure of the second region 2 is a core region 21 having a refractive index n 21 and a refractive index n located on both sides of the core region 2122 It has a cladding region 22 and is a waveguide that propagates light in the longitudinal direction of the core region 21 in a plurality of transverse modes (i.e., transverse multimodes). The number of transverse modes depends on the width of the core region 21, the refractive index n of the core region 21 21 and the refractive index n of the cladding regions 22 located on both sides of the core region 21 22 . Here, the width of the core region 21 is the width in a direction perpendicular to the stacking direction of the semiconductor stacked portion 101 in a plane perpendicular to the optical axis of the waveguide. Also, the thickness of the core region 21 is the thickness in the stacking direction of the semiconductor stacked portion 101 in a plane perpendicular to the optical axis of the waveguide. Note that the cladding regions 22 are provided on both sides of the core region 21, and the refractive indices of the two cladding regions 22 may be the same as each other or different. When the refractive indices are different, let the respective refractive indices be n 22A and n 22B , and these values can be used as the refractive indices of the cladding regions 22.

[0032] Hereinafter, the number of transverse modes will be described. In the following description, for simplicity, a symmetric three-layer slab waveguide will be described. The number of transverse modes N of the light propagating in the core region 21 can be set based on the following formula 1 by obtaining the normalized frequency V defined by the refractive index n of the core region 21 21 , the refractive index n of the cladding region 22 22 , and the width of the core region 21.

[0033] V≧Nπ / 2 ··· (Formula 1) (N is an integer of 1 or more)

[0034] Here, the normalized frequency V is V = k0n 21 a(2Δ) 1 / 2 . k0 is the wave number in vacuum, a is the half-width of the core region 21, and Δ(=(n 21 2 -n 22 2 ) / (2n 21 2 )) is the relative refractive index difference.

[0035] In Equation 1, N is the mode order of the transverse mode. For example, when the normalized frequency V is equal to or greater than π / 2 and less than 2π / 2 (i.e., π), light can be propagated in two modes, the 0th mode (fundamental mode) and the 1st mode. If the normalized frequency V is equal to or greater than Nπ / 2 and less than (N + 1)π / 2, light can be propagated in a plurality of modes from the 0th, 1st, 2nd,... Nth modes, that is, (N + 1) modes.

[0036] Thus, the number of transverse modes of the light propagating through the second region 2 can be set based on Equation 1. Specifically, it can be set based on the width of the second ridge 135b. Note that even in a semiconductor laser device having no ridge structure, it can be set based on the parameters constituting the waveguide. The larger the number of transverse modes, the more preferable it is for high output. For example, it is 10 or more, preferably 30 or more, and more preferably 50 or more. Although the larger the number of transverse modes, the more preferable it is for high output, if it is too large, there are problems such as deterioration of the condensing property. For example, it is 500 or less, preferably 300 or less, and more preferably 100 or less. As understood from the description regarding Equation 1 described above, the number of transverse modes is determined by parameters including the width of the core region 21. Considering the number of transverse modes and heat dissipation properties described above, the width of the core region 21 is, for example, 15 μm or more and 120 μm or less, and more preferably 45 μm or more and 100 μm or less.

[0037] (Diffraction grating 105) As shown in FIG. 1 and the like, the diffraction grating 105 is provided in the first region 1. The diffraction grating 105 is preferably provided over the entire first region 1. Further, the diffraction grating 105 is not provided in the second region 2. The Bragg wavelength in the diffraction grating is represented by the following Equation 2. Equation 2 shows that the effective period of the diffraction grating is the product of the equivalent refractive index and the pitch of the diffraction grating.

[0038] Bragg wavelength (λ B ) = (equivalent refractive index (n1) × pitch of diffraction grating (P)) × 2... (Equation 2)

[0039] The diffraction grating 105 can be formed by alternately (periodically) providing regions with different refractive indices in the light propagation direction. The diffraction grating 105 is provided, for example, between two adjacent semiconductor layers. The pitch of the diffraction grating 105 can be appropriately selected in consideration of the wavelength of the light emitted by the active layer 120. Note that the equivalent refractive index n1 of the diffraction grating 105 is substantially the same for each transverse mode. Therefore, the Bragg wavelength λ B corresponding to each transverse mode is also substantially the same. Therefore, compared with the case where the equivalent refractive index n1 of the diffraction grating 105 is different for each transverse mode, the full width at half maximum of the spectrum of the laser light emitted from the semiconductor laser element L1 can be reduced. For example, the full width at half maximum of the spectrum of the laser light emitted from the semiconductor laser element L1 is 0.01 nm or more and 0.5 nm or less. Also, the equivalent refractive index n1 of the diffraction grating 105 is the refractive index n1 of the first region 1.

[0040] In Embodiment 1, the diffraction grating 105 is provided, for example, between the n-side optical guide layer 112 and the n-side cladding layer 111. Specifically, the diffraction grating 105 is provided on the surface of the n-side cladding layer 111 and includes one or more first convex portions protruding toward the n-side optical guide layer 112, and one or more second convex portions provided on the surface of the n-side optical guide layer 112 and protruding toward the n-side cladding layer 111, alternately in the light traveling direction. Here, the pitch (P) in Equation 2 is the sum of the length of one first convex portion and the length of one second convex portion in the light propagation direction. In Embodiment 1, the diffraction grating 105 is provided between the n-side optical guide layer 112 and the n-side cladding layer 111, but it may be provided only on either the n-side optical guide layer 112 or the n-side cladding layer 111, or between the n-side optical guide layer 112 and the active layer 120. Also, the diffraction grating 105 may be provided on the p-side semiconductor layer 130 side.

[0041] (Electrode) As shown in FIGS. 3 to 4, the semiconductor laser element L1 includes a p-electrode 150 and an n-electrode 160. The n - electrode 160 can be disposed on the lower surface of the substrate 100 when the substrate 100 has conductivity, for example. When the substrate 100 has insulation, a part of the n - side clad layer 111 can be exposed and formed on the exposed surface. As materials for the p - electrode 150 and the n - electrode 160, for example, single - layer films or multi - layer films such as metals or alloys such as Ni, Rh, Cr, Au, W, Pt, Ti, Al, and conductive oxides containing at least one selected from Zn, In, Sn can be mentioned.

[0042] Note that the p - electrode 150 may include a transparent conductive film in contact with the ridge 135 as the first electrode. By selecting a material such that the refractive index of the transparent conductive film is smaller than the refractive index of the active layer 120 or the p - side semiconductor layer 130, the transparent conductive film can also be treated as the p - side clad layer. The transparent conductive film is, for example, ITO (indium - tin oxide), IGZO (indium - gallium - zinc oxide), etc. The insulating film 140 may be, for example, silicon oxide, aluminum oxide, or aluminum nitride.

[0043] (Calculation of the maximum divergence angle Θ max1 ) In the semiconductor laser element L1 of Embodiment 1, the maximum divergence angle Θ max1 referred to when setting the position of the current blocking structure 10 is an index M 2 factor indicating the quality of the laser beam, and can be obtained using the M 2 factor. The M 2 factor is an index indicating the spread from an ideal Gaussian beam, and in an ideal Gaussian beam, the M 2 factor is 1. That is, if the M max1 factor of the laser light output from the semiconductor laser element L1 is known, it is possible to know how much the laser light is spread compared to an ideal Gaussian beam, and the maximum divergence angle Θ

[0044] M 2 = πφW0 / λ ···(Equation 3) Here, W0 is the beam waist radius and φ is the beam divergence angle. Also, λ is the wavelength of the laser light in a vacuum.

[0045] The beam waist radius W0 and the beam divergence angle φ can be measured as follows using an optical system equipped with a collimating lens 81 and a focusing lens 82 shown in FIG. 5. The laser light emitted from the first region 1 is made parallel by the collimating lens 81, and the locus of the focused laser light is traced by the focusing lens 82. Specifically, the beam diameter of the laser light after focusing is measured at various positions Bmp, the position where the beam diameter is the smallest is estimated, and the beam diameter (beam waist radius W0) at that position is obtained. The beam divergence angle φ is obtained by measuring the spread of the beam from the position where the beam diameter is the smallest. Note that M 2 The definition of the parameters necessary for obtaining the M factor is based on the international standard ISO 11146-1:2021 or ISO 11146-2:2021. The beam diameter is defined by D4σ (second moment width). Note that M 2 The current value applied to the semiconductor laser element L1 when measuring the M factor is within the range of the defined driving current.

[0046] Based on the beam waist radius W0 and the beam divergence angle φ obtained as described above, the M 2 factor is calculated, and as described above, the M 2 Based on the factor, the maximum divergence angle Θ max1 is obtained. M 2 The M factor and 2 Based on the trajectory of the laser light measured in the process of obtaining the M factor, the trajectory of the laser light emitted from the second region 2 can be known. As a result, a virtual line v1 that spreads at the maximum divergence angle Θ max1 from both ends of the emission end face of the core region 21 is obtained. By comparing the positional relationship between this virtual line and both ends of the first region 1, the spread of the laser light in the first region 1 can be examined. Here, the maximum divergence angle Θ max1 refers to the angle formed by a straight line excluding the curved portion on the virtual line and a straight line extending the boundary between the core region 21 and the cladding region 22, as shown in FIG. 5 and the like. In addition, the M of the laser beam in Embodiment 1 2 factor may be 2 or more and 100 or less. Note that when the beam diameter of the laser beam at the laser beam output end face is smaller than the width of the first region 1 and the width of the first region 1 is substantially constant, it is obvious that both ends of the first region 1 are located outside the virtual line v1. Therefore, first, by measuring the beam diameter of the laser beam at the laser beam output end face, the positional relationship between the width of the first region 1 and the virtual line v1 can be understood. With such a structure, variations in the oscillation wavelength can be reduced.

[0047] In the above Embodiment 1, the semiconductor laser element L1 of Embodiment 1 has been described by taking the semiconductor laser element having a ridge structure as an example. However, the semiconductor laser element L1 of Embodiment 1 is not limited to the semiconductor laser element having a ridge structure, and may be a rib waveguide type semiconductor laser element or an embedded hetero structure waveguide type semiconductor laser element.

[0048] The semiconductor material constituting the semiconductor laser element described so far may be a material other than a nitride semiconductor. The semiconductor material may be, for example, GaAs, InP, GaInP, GaInAsP, GaAlAs, or AlInGaP. At this time, it may be used as a semiconductor laser element having an oscillation wavelength of 760 nm or more and 1060 nm or less. Also, the semiconductor laser element may be constituted by materials other than these. For example, a semiconductor laser element that emits ultraviolet light may be constituted using aluminum nitride, boron nitride, or the like.

[0049] Embodiment 2 The semiconductor laser element L2 of Embodiment 2 is the same as the semiconductor laser element L1 of Embodiment 1 in that it includes a current blocking structure 10 formed of a part of the insulating film 140, but the configuration of the p electrode 150 is different. Specifically, in the semiconductor laser element L2 of Embodiment 2, in the first region 1, instead of providing the first electrode 151 in contact with the entire upper surface of the p-side contact layer 133 on the ridge 135 of the semiconductor stack 101, as shown in FIG. 6, the first electrode 151 is provided so as to be embedded in the opening region 140a, and the first electrode 151 is brought into contact with the p-side contact layer 133 by restricting it to the opening region 140a. That is, in the semiconductor laser element L2 of Embodiment 2, the first electrode 151 provided in contact with the semiconductor stack 101 is not provided at a position overlapping the insulating film 140. With this configuration, the possibility of current spreading laterally in the first electrode 151 is reduced, and current can be shielded more effectively.

[0050] The semiconductor laser element L2 of Embodiment 2 configured as described above can reduce the current injected into the first region 1, suppress the ineffective current in the first region 1, and reduce heat generation. Therefore, the semiconductor laser element L2 of Embodiment 2 can achieve high output by oscillating and propagating laser light in a plurality of transverse modes, and can provide a semiconductor laser element L1 with high power conversion efficiency. Here, in the semiconductor laser element L2 of Embodiment 2, the first electrode 151 is provided so as to be embedded in the opening region 140a and the first electrode 151 is brought into contact with the p-side contact layer 133 by restricting it to the area of the opening region 140a. Therefore, the possibility of current spreading laterally in the first electrode 151 is reduced as in the semiconductor laser element L1 of Embodiment 1, and current can be shielded more effectively. In the semiconductor laser element L2 of Embodiment 2, the structure of the p-electrode 150 in the second region 2 is not particularly limited, and it may be the same as in Embodiment 1, or the first electrode 151 may be provided so as to be embedded in the opening 140b. Also, in the semiconductor laser element L2 of Embodiment 2, the configuration other than the p-electrode 150 is the same as that of the semiconductor laser element L1 of Embodiment 1. For example, the semiconductor laser element L2 is a transverse multimode type semiconductor laser element.

[0051] Embodiment 3 In the semiconductor laser element L3 of Embodiment 3, the configuration of the current blocking structure 13 is different from that of the semiconductor laser element L1 of Embodiment 1. Specifically, as shown in FIG. 7, the current blocking structure 13 in the semiconductor laser element L3 of Embodiment 3 is provided on the surface of the semiconductor stack portion 101 (the surface of the p-side contact layer 133), and is composed of an oxide film 133a having one or more opening regions 13a. Current is injected from the p electrode 150 into the semiconductor stack portion 101 of the first region 1 through the opening region 13a. The oxide film 133a is, for example, a film formed by oxidizing a part of the semiconductor stack portion 101. By forming the current blocking structure 10 with the oxide film 133a, a part of the semiconductor stack portion 101 can be used as a structure for insulation, and since there is no need to provide a separate structure for insulation, member savings are possible. Note that the oxide film 133a is, for example, a film composed of an oxide containing gallium and nitrogen. Here, in the semiconductor laser element L3 of Embodiment 3, for example, in the first region 1, the first electrode 151 can be provided so as to contact the entire upper surface of the p-side contact layer 133 on the ridge 135 of the semiconductor stack portion 101.

[0052] In the semiconductor laser element L3 of Embodiment 3, the oxide film 133a constituting the current blocking structure 13 can be formed, for example, by oxidizing the surface of the p-side contact layer 133. In this way, the first electrode 151 and the p-side contact layer 133 can be Schottky-jointed via the oxide film 133a, and the current blocking structure 13 can be constituted. The semiconductor laser element L3 of Embodiment 3 configured as described above can reduce the amount of current injected into the first region 1, suppress the idle current in the first region 1, and reduce heat generation. Therefore, the semiconductor laser element L3 of Embodiment 3 can achieve high output by oscillating and propagating laser light in a plurality of transverse modes, and can provide a semiconductor laser element L3 with high power conversion efficiency. Furthermore, in the semiconductor laser device L3 of Embodiment 3, the current injection structure in the second region 2 is not particularly limited, and may be the same as that in Embodiment 1 or may have another configuration. For example, in the second region 2, a second oxide film provided on the semiconductor layer structure and having continuous openings on the waveguide may be provided, and current may be injected into the second region 2 through the openings. By doing so, in the second region 2, it becomes possible to provide a core region 21 and clad regions 22 on both sides thereof, and light of a plurality of modes can be oscillated corresponding to the width of the openings. In addition, in the semiconductor laser device L3 of Embodiment 3, the configuration of the semiconductor stacked portion 101 and the like other than the current shielding structure 13 is the same as that of the semiconductor laser device L1 of Embodiment 1. For example, the semiconductor laser device L3 is a lateral multimode semiconductor laser device.

[0053] Embodiment 4 The semiconductor laser device L4 of Embodiment 4 is different from the semiconductor laser device L1 of Embodiment 1 in the configuration of the current shielding structure 14. Specifically, as shown in FIG. 8, the current shielding structure 14 in the semiconductor laser device L4 of Embodiment 4 is provided in the p-side semiconductor layer 130 of the semiconductor stacked portion 101 and is constituted by a current blocking layer 132a having an opening region 14a in the first region 1, and is configured by restricting the current injected from the p electrode 150 by the opening region 14a. The current blocking layer 132a is an undoped layer substantially free of impurities such as Si and Mg and is a layer for shielding current. By forming the current shielding structure 10 with the current blocking layer 132a, a structure for insulation can be provided at a predetermined position inside the p-side semiconductor layer 130. Here, in the semiconductor laser device L4 of Embodiment 4, for example, in the first region 1, the first electrode 151 can be provided so as to be in contact with the entire upper surface of the p-side contact layer 133 on the ridge 135 of the semiconductor stacked portion 101. The current blocking layer 132a can be provided by forming an undoped layer in a part of the p-side semiconductor layer 130.

[0054] In FIG. 8, an example is shown in which a current blocking layer 132a is provided by making a part of the p-side clad layer 132 undoped. However, it may be provided on the active layer 120, that is, on the p-electrode 150 side. For example, it may be provided on the p-side optical guide layer 131 or the p-side contact layer 133. An undoped layer may be provided as a new layer in addition to the p-side optical guide layer 131, the p-side clad layer 132, and the p-side contact layer 133 in the p-side semiconductor layer 130 to form the current blocking layer 132a. The semiconductor laser element L4 of Embodiment 4 configured as described above can limit the amount of current injected into the first region 1, suppress the idle current in the first region 1, and reduce heat generation. Therefore, according to the semiconductor laser element L4 of Embodiment 4, since laser light can be oscillated and propagated in a plurality of transverse modes, high output can be achieved, and a semiconductor laser element L3 with high power conversion efficiency can be provided. Note that, in the semiconductor laser element L3 of Embodiment 3, the current injection structure in the second region 2 is not particularly limited, and may be the same as that in Embodiment 1 or may have another configuration. For example, in the second region 2, a current blocking layer provided on the semiconductor layer structure and having an opening on the waveguide may be provided, and current may be injected into the second region 2 through the opening. By doing so, in the second region 2, it becomes possible to provide a core region 21 and clad regions 22 on both sides thereof, and light in a plurality of modes can be oscillated corresponding to the width of the opening. Also, in the semiconductor laser element L4 of Embodiment 4, the configuration of the semiconductor laminated portion 101 and the like other than the current shielding structure 14 is the same as that of the semiconductor laser element L1 of Embodiment 1. For example, the semiconductor laser element L4 is a transverse multimode type semiconductor laser element.

[0055] In the description of the above embodiments, an example in which a plurality of opening regions 140a constituting the current shielding structure 10 are provided has been illustrated and described. However, at least one opening region 140a constituting the current shielding structure 10 may be provided. In this way, when reducing the number of the opening regions 140a to one or several, for example, as shown in FIG. 9, it is preferably provided at the center of the first region 1 (the region where the light with high intensity among the light incident from the second region 2 propagates). In this case, the area of the opening region 140a is 25 μm 2 or more and 150 μm 2 or less. Here, in FIG. 9, the opening regions 140a of the first and second embodiments have been illustrated and described. Similarly, at least one opening region 140a may be provided for the opening region 13a of the third embodiment and the opening region 14a of the fourth embodiment as well. In addition, in the description of the above embodiments, an example in which the opening region 140a constituting the current shielding structure 10 is circular in a top view has been illustrated and described. As described above, since the opening region 140a is circular, the amount of current flowing through the opening region 140a can be made uniform. However, the shape of the opening region 140a is not limited to a circle and can be various shapes. For example, it may be a polygon such as a rectangle, or an ellipse. For example, FIG. 10 shows an example in which, instead of the circular opening region 140a in a top view, a rectangular opening region 140a1 is provided in a strip shape. FIG. 10 shows an example in which a plurality of rectangular opening regions 140a1 are provided such that their major axes are parallel to each other in a top view. However, for example, in a top view, the rectangular opening regions 140a1 may be provided such that their major axes spread radially as they are away from the second region. By making the opening region 140a rectangular, the opening region 140a can be easily provided. In addition, in FIG. 10, a plurality of opening regions 140a1 are provided dispersed throughout the first region 1. However, a plurality of opening regions 140a1 may be provided in a strip shape only at the center of the first region 1 (the region where the light with high intensity among the light incident from the second region 2 propagates). In this way, one or more opening regions 140a may be provided only in the region inside the virtual line that spreads at the maximum diffusion angle Θ max1 of the first region 1. With this configuration, the current flowing through the region in the first region 1 where light does not propagate can be reduced. Further, compared with the case where the opening region 140a1 is provided over the entire first region 1, the number of the opening regions 140a may be reduced. In this case, the opening regions 140a1 with the reduced number are preferably provided in the central portion of the first region 1 (the region through which the light with high intensity among the light incident from the second region 2 propagates).

[0056] Other configurations Further, for example, the present disclosure can have the following configurations. (Item 1) A semiconductor laser element having a semiconductor laminate portion that includes an active layer and has a waveguide structure, wherein the semiconductor laminate portion (i) includes a first region including a diffraction grating, and (ii) includes a second region having a core region and clad regions provided on both sides of the core region, and propagating laser light in a plurality of transverse modes, and in the direction in which the core region and the clad regions are arranged, the width of the first region is wider than the width of the core region, in a top view, a current blocking structure is provided at a position overlapping with the first region, the current blocking structure has one or a plurality of opening regions for injecting current into the semiconductor laminate portion in the first region, in a top view, the total area of the one or the plurality of opening regions is smaller than the area of the first region, the semiconductor laser element. (Item 2) the refractive index of the first region is n1, the refractive index of the core region is n 21 and the refractive index of the clad region is n 22 and the laser light emitted from the second region propagates through the first region at a maximum divergence angle Θ 21 determined by the refractive index n1, the refractive index n 22 and the refractive index n max1 The semiconductor laser element according to Item 1. (Item 3) The semiconductor laser device according to claim 1, wherein the one or more opening regions are circular. (Claim 4) The semiconductor laser device according to claim 1, wherein the one or more opening regions are rectangular. (Claim 5) The semiconductor laser device according to claim 1 or 2, wherein the current blocking structure is an insulating film provided on the semiconductor stack. (Claim 6) The semiconductor laser device according to claim 1 or 2, wherein the current blocking structure is an oxide film provided on the surface of the semiconductor stack. (Claim 5) The semiconductor laser device according to claim 1 or 2, wherein the current blocking structure is a current blocking layer provided in the semiconductor stack. (Claim 7) Furthermore, an electrode that is provided in contact with the semiconductor stack and that contacts the semiconductor stack is included, The semiconductor laser device according to any one of claims 1 to 5, wherein the electrode is provided at a position overlapping the current blocking structure in a top view. (Claim 8) Furthermore, an electrode that is provided in contact with the semiconductor stack and that contacts the semiconductor stack is included, The semiconductor laser device according to any one of claims 1 to 5, wherein the electrode is not provided at a position overlapping the current blocking structure in a top view.

[0057] Although the embodiments and modified examples of the present disclosure have been described above, various modifications are possible as long as the configuration is based on the technical idea of the present disclosure. Also, various changes are possible within the scope of the present disclosure and the scope of the idea by changing the combination and order of the constituent elements in the embodiments and modified examples.

Description of Reference Numerals

[0058] L1, L2, L3, L4 Semiconductor laser device 1 First region 2 Second region 10, 13, 14 Current blocking structure 21 Core region 22 Clad region 100 Substrate 101 Semiconductor laminate 150 p electrode 151 First electrode 152 Second electrode 160 n electrode 110 n-side semiconductor layer 111 n-side cladding layer 112 n-side optical guide layer 120 Active layer 130 p-side semiconductor layer 131 p-side optical guide layer 132 p-side cladding layer 132a Current blocking layer 133 p-side contact layer 133a Oxide film 105 Diffraction grating 135 Ridge 135a First ridge 135b Second ridge 140 Insulating film 140a Opening region 140b Opening

Claims

1. A semiconductor laser device having a semiconductor laminate portion that includes an active layer and has a waveguide structure, where the semiconductor laminate portion includes (i) a first region that includes a diffraction grating, and (ii) a second region that has a core region and clad regions provided on both sides of the core region and propagates laser light in a plurality of transverse modes, and in a direction in which the core region and the clad regions are arranged, the width of the first region is wider than the width of the core region, in a top view, a current blocking structure is provided at a position overlapping the first region, the current blocking structure has one or more opening regions that inject current into the semiconductor laminate portion in the first region, in a top view, the total area of the one or more opening regions is smaller than the area of the first region, a semiconductor laser device.

2. The refractive index of the first region is n １ and The refractive index of the core region is n ２１ and The refractive index of the clad region is n ２２ and The laser light emitted from the second region has a refractive index n １ and the refractive index n ２１ and the refractive index n ２２ and propagates through the first region at a maximum divergence angle Θ max１ determined thereby. The semiconductor laser device according to claim 1

3. The semiconductor laser device according to claim 1, wherein the one or more opening regions are circular.

4. The semiconductor laser device according to claim 1, wherein the one or more opening regions are rectangular.

5. The semiconductor laser device according to claim 1, wherein the current blocking structure is an insulating film provided on the semiconductor laminate portion.

6. The semiconductor laser device according to claim 1, wherein the current blocking structure is an oxide film provided on the surface of the semiconductor laminate portion.

7. The semiconductor laser device according to claim 1, wherein the current blocking structure is a current blocking layer provided in the semiconductor laminate portion.

8. Further, it is provided in contact with the semiconductor laminate portion and includes an electrode that contacts the semiconductor laminate portion, in a top view, the electrode is provided at a position overlapping the current blocking structure, the semiconductor laser device according to any one of claims 1 to 5.

9. Further, it is provided in contact with the semiconductor laminate portion and includes an electrode that contacts the semiconductor laminate portion, in a top view, the electrode is not provided at a position overlapping the current blocking structure, the semiconductor laser device according to any one of claims 1 to 5.

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