Multi-beam semiconductor laser element

Abstract

To provide a multi-beam semiconductor laser element in which a multilayer wiring structure over a laser resonator is unnecessary.SOLUTION: A plurality of laser waveguides 200 are integrated onto a semiconductor substrate 110 so as to be adjacent in a first direction (an x-direction). Each laser waveguide 200 includes a stripe-like power supply electrode 150 in which a second direction (a y-direction) that is vertical to the first direction is a longitudinal side. An inter-layer insulation layer 160 is formed onto the power supply electrode 150 of the plurality of laser waveguides 200. A plurality of pad electrodes PE are arranged along the second direction onto the inter-layer insulation layer 160. In each pad electrode PE, electric connection means 320 that corresponds at a mounting is connected. The plurality of pad electrodes PE correspond to the plurality of laser waveguides 200, and each pad electrode PE overlaps with the power supply electrode 150 of the corresponding laser waveguide 200 in at least one part, and is electrically connected.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a multi-beam semiconductor laser device. [Background technology]

[0002] Semiconductor lasers are used as light sources in electronic devices such as printers and head mounted displays (HMDs). To accommodate the increasing resolution of such electronic devices that handle images, multi-beam semiconductor laser elements are being adopted.

[0003] In order to miniaturize lenses and MEMS mirrors, it is necessary to narrow the beam pitch. If the beam pitch becomes narrower than the width of the pad electrode, the pad electrode must be formed closer to the edge of the chip (semiconductor substrate). In this case, the connection wiring that connects the pad electrode and the laser waveguide must straddle the laser waveguide (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-135731 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present inventors have studied narrow-beam-pitch multi-beam semiconductor laser devices and have come to recognize the following problems.

[0006] Focusing on the intersection of the connection wiring and the laser waveguide, an interlayer insulating film is inserted between the connection wiring and the power supply electrode of the laser electrode, forming a multilayer wiring structure. Such a multilayer wiring structure requires a complex semiconductor manufacturing process. If the pitch of the laser waveguide becomes narrower, it becomes more difficult to form the multilayer wiring, and the manufacturing process becomes more complicated.

[0007] In addition, since the electrodes formed on the interlayer insulating film have poor adhesion, there is a problem that they are easily peeled off when the width of the electrodes is narrowed, and there is also a problem that the chip width is widened by the amount of the pad electrodes.

[0008] An aspect of the present disclosure has been made in view of the above problems, and one of its exemplary objectives is to provide a multi-beam semiconductor laser element that does not require a stacked wiring structure spanning a laser cavity. [Means for solving the problem]

[0009] A multi-beam semiconductor laser element according to an embodiment of the present disclosure includes a plurality of laser waveguides integrated adjacent to each other in a first direction on a semiconductor substrate, an interlayer insulating film, and a plurality of pad electrodes. Each laser waveguide has a stripe-shaped power supply electrode extending in a second direction perpendicular to the first direction. The interlayer insulating film is formed on the power supply electrodes of the plurality of laser waveguides. The plurality of pad electrodes are arranged on the interlayer insulating layer along the second direction. Each pad electrode is connected to a corresponding electrical connection means when mounted. The plurality of pad electrodes correspond to the plurality of laser waveguides, and each pad electrode overlaps and is electrically connected to the corresponding laser waveguide at least in part. The interlayer insulating layer is formed to insulate between the pad electrodes that do not correspond and the power supply electrodes, and to insulate between the power supply electrodes that do not correspond and the electrical connection means.

[0010] Any combination of the above components, or mutual substitution of components or expressions between methods, devices, systems, etc., are also effective as aspects of the present invention or the present disclosure. Furthermore, the description in this section (Means for Solving the Problems) does not explain all essential features of the present invention, and therefore, subcombinations of the described features may also constitute the present invention. Effect of the Invention

[0011] According to an aspect of the present disclosure, a multi-beam semiconductor laser element that does not require a stacked wiring structure spanning a laser cavity can be provided. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view of a semiconductor laser device according to a first embodiment. [Diagram 2] FIG. 2 is a plan view of the semiconductor laser device of FIG. [Diagram 3] FIG. 2 is a cross-sectional view of the semiconductor laser device of FIG. [Figure 4] 2 is a diagram showing a semiconductor laser device including the semiconductor laser element of FIG. 1. [Diagram 5] FIG. 1 is a plan view of a conventional semiconductor laser device. [Figure 6] FIG. 2 is an enlarged cross-sectional view of the periphery of a pad electrode. [Figure 7] FIG. 11 is a plan view of a semiconductor laser device according to a second embodiment. [Figure 8] FIG. 11 is a plan view of a semiconductor laser device according to a third embodiment. [Figure 9] FIG. 11 is a plan view of a semiconductor laser device according to a fourth embodiment. [Figure 10] FIG. 11 is a plan view of a semiconductor laser device according to a fifth embodiment. [Figure 11] FIG. 13 is a plan view of a semiconductor laser device according to a sixth embodiment. [Figure 12] FIG. 13 is a plan view of a semiconductor laser device according to a seventh embodiment. [Figure 13] FIG. 13 is a plan view of a semiconductor laser device according to an eighth embodiment. [Figure 14] FIG. 13 is a plan view of a semiconductor laser device according to a ninth embodiment. [Figure 15] 1 is a cross-sectional view of a semiconductor laser device including a semiconductor laser element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (Overview of the embodiment) A summary of some exemplary embodiments of the present disclosure is provided. This summary is intended as a prelude to the more detailed description that follows, or as a basic understanding of the embodiments. This summary is intended to provide a simplified description of some concepts of one or more embodiments, and is not intended to limit the scope of the invention or disclosure. Additionally, this summary is not intended to be a comprehensive overview of all possible embodiments, nor is it intended to limit essential elements of the embodiments. For convenience, the term "one embodiment" may refer to one embodiment (example or variant) or multiple embodiments (examples or variants) disclosed in this specification.

[0014] A multi-beam semiconductor laser element according to one embodiment includes a plurality of laser waveguides integrated adjacent to each other in a first direction on a semiconductor substrate, an interlayer insulating film, and a plurality of pad electrodes. Each laser waveguide has a stripe-shaped power supply electrode extending in a second direction perpendicular to the first direction. The interlayer insulating film is formed on the power supply electrodes of the plurality of laser waveguides. The plurality of pad electrodes are arranged on the interlayer insulating layer along the second direction. Each pad electrode is connected to a corresponding electrical connection means when mounted. The plurality of pad electrodes correspond to the plurality of laser waveguides, and each pad electrode overlaps and is electrically connected to the corresponding laser waveguide at least in part. The interlayer insulating layer is formed to insulate between the pad electrodes and the power supply electrodes that do not correspond to each other, and to insulate between the power supply electrodes and the electrical connection means that do not correspond to each other.

[0015] According to this configuration, by forming the pad electrodes in the region (laser region) where a plurality of laser waveguides are formed, it becomes unnecessary to route the connection wiring, and therefore the need for a laminated wiring structure is eliminated.

[0016] In one embodiment, the interlayer insulating layer may include a plurality of insulating films corresponding to the plurality of laser waveguides and arranged in the second direction. Each insulating film may cover a plurality of power supply electrodes of the plurality of laser waveguides and have an opening at the position of the corresponding power supply electrode.

[0017] In one embodiment, the interlayer insulating layer may include a single insulating film that covers an area of ​​the semiconductor substrate excluding the periphery. The insulating film may have a plurality of openings at positions corresponding to the plurality of pad electrodes.

[0018] In one embodiment, the opening may have a width in the first direction when viewed in a cross section along the second direction that increases from the power supply electrode toward the pad electrode, thereby increasing the width of the pad electrode in the first direction and the contact area with the electrical connection means.

[0019] In one embodiment, the width of the pad electrode in the first direction is preferably 4 μm or more. Alternatively, the width of the pad electrode in the first direction is such that the contact area between the pad electrode and the electrical connection means is 120 μm or more. 2 You may decide to make it larger.

[0020] In one embodiment, the opening may have a divergence angle of 60° or more when viewed in cross section. In one embodiment, the interlayer insulating layer may have a thickness of 1 μm or more. This allows the width of the pad electrode in the first direction to be increased.

[0021] In one embodiment, the interlayer insulating layer may be an organic material, which can facilitate thickening and can simplify the manufacturing process by utilizing photosensitivity.

[0022] In one embodiment, the interlayer insulating layer may include a plurality of insulating films corresponding to the plurality of laser waveguides and arranged in the second direction, and each insulating film may be formed so as to cover an upper portion of a non-corresponding power supply electrode.

[0023] In one embodiment, the multi-beam semiconductor laser device may further include a plurality of reinforcing electrodes corresponding to the plurality of pad electrodes, each reinforcing electrode being disposed adjacent to a corresponding pad electrode such that the reinforcing electrodes are connectable to a common electrical connection means for the corresponding pad electrode.

[0024] In one embodiment, the multi-beam semiconductor laser element may further include a plurality of reinforcing electrodes corresponding to the plurality of pad electrodes, each reinforcing electrode having a shape surrounding the corresponding pad electrode so as to be connectable to a common electrical connection means for the corresponding pad electrode.

[0025] In one embodiment, when the number of laser waveguides is n and the pitch of the laser waveguides is P, the chip width Wchip of the multi-beam semiconductor laser element is Wchip<100μm+n×P may satisfy the following relationship.

[0026] In one embodiment, the multi-beam semiconductor laser element may be mounted in a junction-up manner, and at least one of the pad electrodes of the multi-beam semiconductor laser element may be connectable to a bonding wire serving as an electrical connection means.

[0027] In one embodiment, when the distance between the laser waveguides is D and the wire diameter of the bonding wire is φ, D<φ and D≦25 μm.

[0028] In one embodiment, the multi-beam semiconductor laser element may further include a back electrode (N-side electrode) formed on a surface of the semiconductor substrate opposite to the surface on which the power supply electrode is formed and connectable to a submount of the CAN package. Each of the multiple pad electrodes may be connectable to a corresponding lead pin of the CAN package via a bonding wire serving as an electrical connection means.

[0029] A can-packaged semiconductor laser device according to an embodiment may include the above-mentioned multi-beam semiconductor laser element, a submount, a metal stem, and a plurality of lead pins. The multi-beam semiconductor laser element may be mounted on the metal stem in a junction-up state on the submount. The pad electrodes and the lead pins may be connected by bonding wires, which are electrical connection means.

[0030] (Embodiment) Hereinafter, the present disclosure will be described with reference to the drawings based on preferred embodiments. The same or equivalent components, parts, and processes shown in each drawing will be given the same reference numerals, and duplicated descriptions will be omitted as appropriate. In addition, the embodiments are not intended to limit the disclosure, but are merely examples, and all features and combinations thereof described in the embodiments are not necessarily essential to the disclosure.

[0031] The dimensions (thickness, length, width, etc.) of each component shown in the drawings may be enlarged or reduced as appropriate for ease of understanding. Furthermore, the dimensions of multiple components do not necessarily represent their relative sizes. Even if a component A is drawn thicker than another component B on the drawings, component A may actually be thinner than component B.

[0032] (Embodiment 1) 1 is a perspective view of a semiconductor laser device 100 according to embodiment 1. The semiconductor laser device 100 is an edge-emitting semiconductor laser device, and is a multi-beam semiconductor laser having a plurality of m emitters (m≧2). In this embodiment, the number of emitters is three.

[0033] The semiconductor laser element 100 includes an N-type semiconductor substrate 110 and a laminated growth layer 120 formed on the N-type semiconductor substrate 110. The laminated growth layer 120 includes an N-type cladding layer 122, an emission layer 130, a P-type cladding layer 124, and a P-type contact layer (not shown), which are laminated in this order on the N-type semiconductor substrate 110. The emission layer 130 includes an N-type guide layer (lower guide layer), an active layer made of a quantum well layer, and a P-type guide layer (upper guide layer). The materials of the N-type semiconductor substrate 110 and the laminated growth layer 120 may be selected according to the required oscillation wavelength, and are not particularly limited in the present disclosure.

[0034] The semiconductor laser device 100 has m (m≧3) laser waveguides 200 adjacent to each other in a first direction (x direction). Each laser waveguide 200 has a stripe structure extending in a second direction (y direction) perpendicular to the first direction (x direction).

[0035] A waveguide structure for confining light is formed in the laminated growth layer 120, and the cleavage planes at both ends of this waveguide structure serve as mirrors to form a Fabry-Perot type laser waveguide 200. In this example, three laser waveguides 200_1 to 200_3 are formed, and a beam is emitted in the y direction from the emission end face. The end face of each laser waveguide is coated to provide a desired reflectance. The laser waveguide 200 may be an external cavity laser, a DBR laser, or a DFB laser.

[0036] The waveguide structure may be, for example, a ridge structure. The ridge structure is formed by partially removing the P-type cladding layer 124. The ridge structure is also simply called a ridge or a ridge stripe structure. A bank may be formed between adjacent laser waveguides 200. The waveguide structure may be a buried ridge waveguide.

[0037] Alternatively, the waveguide structure may be a CSP (Channeled Substrate Planar) structure in which a groove is formed in the N-type semiconductor substrate 110 along the waveguide, and the thickness of the N-type cladding layer 122 in the groove is relatively thick.

[0038] The ridge structure and the CPS structure are waveguide structures that utilize a refractive index distribution, but the present disclosure is not limited thereto, and a gain waveguide structure that utilizes a gain distribution may be used. These structures are light confinement structures, and can also be understood as current confinement structures.

[0039] A power supply electrode (P-side electrode) 150 is formed on the upper surface of each laser waveguide 200. In order to enable the laser waveguides 200 to be driven independently, the power supply electrodes 150 are electrically insulated from each other. In this embodiment, the power supply electrode 150 is a stripe-shaped electrode extending along the y direction on the upper surface of the laser waveguide 200.

[0040] An interlayer insulating layer 160 is formed on the power supply electrode 150. A plurality of pad electrodes PE1 to PE3 corresponding to the plurality of laser waveguides 200 are formed on the interlayer insulating layer 160. Each pad electrode PEi (i=1, 2, 3) is formed so as to at least partially overlap with the corresponding power supply electrode 150_i and is electrically connected to it.

[0041] The pad electrodes PE1 to PE3 are connected to electrical connection means such as bonding wires when mounting the semiconductor laser device 100. In FIG.

[0042] The interlayer insulating layer 160 insulates between the non-corresponding pad electrodes PEi and the power supply electrodes 150_j (where j≠i). Furthermore, the interlayer insulating layer 160 is formed so as to insulate between the non-corresponding power supply electrodes 150_i and the electrical connection means 320_j (where j≠i).

[0043] In this embodiment, the interlayer insulating layer 160 includes a plurality of interlayer insulating films (hereinafter, simply referred to as insulating films) 162_1 to 162_3 arranged in the second direction (y direction). As the material of the insulating film 162, inorganic insulating film materials such as Al2O3, AlN, SiO2, and SiN formed by CVD (Chemical Vapor Deposition) or sputtering, and organic insulating film materials such as polyimide can be used. Inorganic materials have an advantage of better heat dissipation than organic materials in terms of thermal conductivity. Polyimide has an advantage that it can fill the unevenness of the base and the surface is easily made flat, so that the connection electrodes Lc can be flattened, but it is difficult to form it thin, which makes it difficult to cleave and pelletize.

[0044] The insulating films 162_1 to 162_3 correspond to the laser waveguides 200_1 to 200_3. Each insulating film 162_i (i=1, 2, 3) has a width in the first direction (x direction) larger than a region (called a laser region) 102 in which the laser waveguides 200_1 to 200_3 are formed, and covers the power supply electrodes 150_1 to 150_3. An opening is formed in each insulating film 162_i at a position overlapping the corresponding power supply electrode 150_i, and the corresponding insulating film 162_i and the power supply electrode 150_i are electrically connected through the opening.

[0045] Fig. 2 is a plan view of the semiconductor laser device 100 of Fig. 1. The insulating films 162_1 to 162_3 are rectangular having the same width and are arranged side by side in the y direction. An opening 163_i is formed in each interlayer insulating layer 160_i (i=1, 2, 3), and a pad electrode PEi is formed on the opening 163.

[0046] 2, the area in contact with the electrical connection means (e.g., a bonding ball) is indicated by a dashed line 320, and the bonding wire is indicated by a solid line 321. For example, the diameter of the bonding ball is 100 μm, the diameter of the bonding wire is 25 μm, and the interval D between adjacent laser waveguides (emitters) 200 is 20 μm. Therefore, the interval D between the emitters is smaller than the diameter φ of the bonding wire 321, and the following relationship holds: D<φ

[0047] That is, in a semiconductor laser element in which the emitter spacing D is equal to or smaller than the bonding wire diameter of 25 μm, a structure capable of independently driving a plurality of laser waveguides 200 can be provided by a simple process.

[0048] 3 is a cross-sectional view of the semiconductor laser device 100 of FIG. 1. The cross-sectional view of FIG. 3 shows a cross section at a position where the pad electrode PE1 is to be formed. A contact insulating film 154 is formed on the P-type cladding layer 124. The contact insulating film 154 has an opening in a ridge portion, and the power supply electrodes 150_1 to 150_3 are formed on this opening. An insulating film 162_1 is formed so as to cover the power supply electrodes 150_1 to 150_3. An opening 163 is formed in the insulating film 162_1 at a position overlapping with the power supply electrode 150_1, and the pad electrode PE1 is formed on this opening 163.

[0049] Fig. 4 is a diagram showing a semiconductor laser device 300 including the semiconductor laser element 100 of Fig. 1. In addition to the semiconductor laser element 100, the semiconductor laser device 300 includes a support substrate 310 and bonding wires 320. The semiconductor laser element 100 is mounted on the support substrate 310 in a junction-up manner, that is, with the N-side electrode 152 facing the support substrate 310.

[0050] An electrode 312 is formed on the support substrate 310. The N-side electrode 152 of the semiconductor laser device 100 is connected to a part of the electrode 312 formed on the support substrate 310 via solder 322. A bonding wire 314 is connected to another part of the electrode 312.

[0051] 4. The pad electrode PE1 of the semiconductor laser device 100 is connected to the electrode 312 via a bonding wire 320. The dashed line 320 in FIG.

[0052] The above is the configuration of the semiconductor laser element 100 and the semiconductor laser device 300. According to the semiconductor laser element 100, bonding wires, which are electrical connection means, can be connected onto the power supply electrodes 150_1-150_3 via the interlayer insulating layer 160, making laminated wiring across the laser waveguide 200 unnecessary.

[0053] Eliminating the need for multilayer wiring can simplify the manufacturing process and reduce manufacturing costs of the semiconductor laser device 100. Furthermore, eliminating the need for unreliable multilayer wiring can improve the reliability of the semiconductor laser device 100.

[0054] 5 is a plan view of a conventional semiconductor laser element 100R. Conventionally, it has been necessary to form pad electrodes P1 to P3 for bonding wires adjacent to a laser region 102 in which a plurality of laser waveguides 200 are formed. The width of the laser region 102 is P×n, where P is the pitch (emitter pitch) of one laser waveguide 200 (emitter) and n is the number of waveguides. If the pelletizing margin is Δx and the width of the wire bonding area is WB, the chip width of the semiconductor laser element 100R is n×P+WB+2×Δx If WB+2×Δx is approximately 100 μm, the conventional chip width is n×P+100μm It becomes.

[0055] In contrast, in the semiconductor laser element 100 according to the embodiment, the pad electrodes of the bonded wires can be formed to overlap the laser waveguides 200_1 to 200_3, so that the chip width Wchip of the semiconductor laser element 100 can be narrower than the conventional chip width, and thus the chip area can be reduced. In other words, the chip width Wchip satisfies the following formula. Wchip <n×P+100μm

[0056] 6 is an enlarged cross-sectional view of the periphery of the pad electrode PE1. The larger the area of ​​the pad electrode PE1, the larger the contact area with the bonding wire 320, and the stronger the mechanical connection strength. As an example, the contact area Sc between the pad electrode PE and the electrical connection means 320 is 120 μm 2 It is preferable that the width of the pad electrode PE in the first direction is larger than Sc>120 μm. 2 It is preferable that the thickness is 4 μm or more.

[0057] For this reason, the width W1 of the pad electrode PE1 is wider than the width W2 of the power supply electrode 150. The opening 163 formed in the insulating film 162_1 has a width tapered from bottom to top when viewed in cross section along the second direction. The taper angle θ of the opening 163 is preferably 60° or more, which allows the width W1 of the pad electrode PE to be widened. The same applies to the pad electrodes PE2 and PE3.

[0058] The thickness of the interlayer insulating layer 160 may be thicker than 1 μm. This allows the width of the pad electrode PE to be widened even if the taper angle θ is small. For the interlayer insulating layer 160, an organic material such as polyimide may be selected. This makes it easy to make the film thick, and the manufacturing process can be simplified by utilizing the photosensitivity.

[0059] (Embodiment 2) 7 is a plan view of a semiconductor laser device 100A according to embodiment 2. An interlayer insulating layer 160A of the semiconductor laser device 100A has one insulating film 162. The insulating film 162 has openings 163_i at positions where the pad electrodes PEi and the power supply electrodes 150_i (i=1 to 3) overlap. The insulating film 162 can be understood as insulating films 162_1 to 163 in FIG. 1 formed continuously in the y direction.

[0060] (Embodiment 3) 8 is a plan view of a semiconductor laser device 100B according to the third embodiment. An interlayer insulating layer 160B of the semiconductor laser device 100B has a plurality of insulating films 162_1-162_3 corresponding to the plurality of power supply electrodes 150_1-150_3. The insulating films 162_1-162_3 are formed adjacent to each other in the y direction. Unlike FIG. 1, each insulating film 162_i does not have an opening and is formed so as to cover, in the x direction, the power supply electrodes 150_j (j≠i) other than the corresponding power supply electrode 150_i (i.e., non-corresponding power supply electrodes).

[0061] The length of each pad electrode PEi in the y direction is substantially the same as that of the corresponding insulating film 162_i. According to the configuration of the third embodiment, the area of ​​the pad electrode PE can be increased compared to that of FIG.

[0062] (Embodiment 4) 9 is a plan view of a semiconductor laser device 100C according to embodiment 4. In the semiconductor laser device 100C, the width of the insulating films 162_1 to 162_3 is substantially the same as the width of the laser region 102. In each of the insulating films 162_i (i=1, 2, 3), an opening 163_i is formed at a position overlapping with a corresponding pad electrode PEi.

[0063] The semiconductor laser device 100C includes a plurality of reinforcing electrodes SE1 to SE3 in addition to a plurality of pad electrodes PE1 to PE3. Each reinforcing electrode SEi is formed so as to sandwich an insulating film 162_i in the x direction.

[0064] In this semiconductor laser element 100C, one bonding wire 320_i comes into contact not only with the pad electrode PEi but also with the reinforcing electrodes SEi on both sides thereof, thereby making it possible to improve the adhesiveness of the bonding wire 320 to the semiconductor laser element 100.

[0065] (Embodiment 5) Fig. 10 is a plan view of a semiconductor laser device 100D according to embodiment 5. In the semiconductor laser device 100D, the widths of the insulating films 162_1 to 162_3 are wider than those in Fig. 9, and each reinforcing electrode SEi is formed so as to overlap with the corresponding insulating film 162_i. The reinforcing electrodes SE are formed outside the laser region 102 so as not to overlap with the power supply electrodes 150_1 to 150_3.

[0066] According to this semiconductor laser element 100D, similarly to the semiconductor laser element 100C of FIG. 9, one bonding wire 320_i comes into contact not only with the pad electrode PEi but also with the reinforcing electrodes SEi on both sides thereof, thereby improving the adhesion between the semiconductor laser element 100 and the bonding wire 320.

[0067] (Embodiment 6) Fig. 11 is a plan view of a semiconductor laser device 100E according to the sixth embodiment. The semiconductor laser device 100E is different from the semiconductor laser device 100D in Fig. 10 in the reinforcing electrodes SE. In Fig. 11, the reinforcing electrodes SEi extend into the laser region 102 in the x direction and reach the edge of the pad electrodes PEi. The reinforcing electrodes SEi are formed so as to partially overlap with the non-corresponding power supply electrodes 150_j (j ≠ i).

[0068] According to the semiconductor laser element 100E, the contact area between the reinforcing electrodes SEi and the bonding wires 320 is increased compared to the semiconductor laser element 100D of FIG. 10, so that the adhesion between the semiconductor laser element 100 and the bonding wires 320 can be improved.

[0069] (Embodiment 7) Fig. 12 is a plan view of a semiconductor laser device 100F according to embodiment 7. The semiconductor laser device 100F differs from the semiconductor laser device 100E of Fig. 11 in the reinforcing electrodes SE. In Fig. 12, the reinforcing electrodes SEi are formed to sandwich the corresponding pad electrodes PEi in the y direction.

[0070] (Embodiment 8) 13 is a plan view of a semiconductor laser device 100G according to embodiment 8. In the semiconductor laser device 100F, each reinforcing electrode SEi is formed so as to surround the corresponding pad electrode PEi. This increases the contact area between the reinforcing electrode SEi and the bonding wire 320, thereby improving the adhesion between the semiconductor laser device 100 and the bonding wire 320.

[0071] (Embodiment 9) 14 is a plan view of a semiconductor laser device 100H according to embodiment 9. In the semiconductor laser device 100H, the reinforcing electrodes SEi are formed integrally and continuously with the pad electrodes PEi. In other words, the width of the pad electrodes PEi is wider than the width of the laser region 102.

[0072] This increases the contact area between the pad electrode PEi and the bonding wire 320, thereby improving the adhesion between the semiconductor laser element 100 and the bonding wire 320.

[0073] 15 is a cross-sectional view of a semiconductor laser device 40 including a semiconductor laser element 100. The semiconductor laser device 400 is a To-can package type, and includes the semiconductor laser element 100, an LD chip 410, a submount 420, a metal stem 430, a metal cap 440, a glass window 450, and leads 460-463.

[0074] The LD chip 410 is the above-mentioned semiconductor laser element 100, and is provided with a plurality of independently operable laser waveguides 200, and is configured to be able to emit a plurality of beams from the front end face. The LD chip 410 is junction-up mounted on a submount 420, and the submount 420 is fixed to a metal stem 430.

[0075] The metal cap 440 covers the side of the LD chip 410 and supports and fixes the glass window 450 .

[0076] The multiple leads 460-464 penetrate the metal stem 430 in a manner insulated from the metal stem 430. Each pad electrode PE formed on the semiconductor laser element 100, which is the LD chip 410, is connected to a corresponding one of the multiple leads 461-463 via a bonding wire. Also, the N-side electrode of the semiconductor laser element 100 is connected to the lead 460 via a bonding wire (or in another manner without using a bonding wire).

[0077] (Modification) In the embodiment, the number of laser waveguides 200 is three, but the number is not limited to three and may be two or four or more.

[0078] In the embodiment, the semiconductor laser element 100 is mounted in a junction-up manner, but a chip having the same configuration can be mounted in a junction-down manner. In this case, the solder applied to the electrodes formed on the support substrate during mounting serves as the bonding wires 320.

[0079] The embodiments merely illustrate the principles and applications of the present invention, and many modifications and changes in arrangement are permitted to the embodiments without departing from the spirit of the present invention defined in the claims. [Explanation of symbols]

[0080] 100 Semiconductor laser element 102 Laser Region 104,106 Pad Area 110 N-type semiconductor substrate 120 Layered Growth 122 N-type cladding layer 124 P-type cladding layer 130 Light-emitting layer PE pad electrode 150 Power supply electrode 152 N side electrode 154 Contact insulating film 160 Interlayer insulation layer 162 Insulating film 200 Laser Waveguide 300 Semiconductor laser device 310 Support Board 320 Bonding Wire

Claims

1. A multi-beam semiconductor laser element, a plurality of laser waveguides integrated adjacent to each other in a first direction on a semiconductor substrate, each of the laser waveguides having a stripe-shaped power supply electrode extending in a second direction perpendicular to the first direction; an interlayer insulating layer formed on the power supply electrodes of the plurality of laser waveguides; a plurality of pad electrodes arranged on the interlayer insulating layer along the second direction, each pad electrode being to be connected to a corresponding electrical connection means when mounted; Equipped with the plurality of pad electrodes correspond to the plurality of laser waveguides, and each pad electrode at least partially overlaps with and is electrically connected to the power supply electrode of the corresponding laser waveguide; a first insulating layer formed on the first surface of the first insulating film and formed on the second surface of the first insulating film, the first insulating layer being formed on the first surface of the first insulating film and formed on the second surface of the first insulating film;

2. the interlayer insulating layer includes a plurality of insulating films arranged in the second direction corresponding to the plurality of laser waveguides; 2. The multi-beam semiconductor laser device according to claim 1, wherein each insulating film covers a plurality of power supply electrodes of the plurality of laser waveguides and has openings at the positions of the corresponding power supply electrodes.

3. the interlayer insulating layer includes one insulating film covering an area of ​​the semiconductor substrate except for the outer periphery; 2. The multi-beam semiconductor laser device according to claim 1, wherein the insulating film has a plurality of openings at positions corresponding to the plurality of pad electrodes.

4. 4. The multi-beam semiconductor laser element according to claim 2, wherein the width of the opening in the first direction when viewed cross-sectionally along the second direction increases from the power supply electrode toward the pad electrode.

5. 5. The multi-beam semiconductor laser device according to claim 4, wherein a divergence angle of said opening when viewed in cross section is 60[deg.] or more.

6. 5. The multi-beam semiconductor laser device according to claim 4, wherein the thickness of said interlayer insulating layer is 1 [mu]m or more.

7. 2. The multi-beam semiconductor laser device according to claim 1, wherein the interlayer insulating layer is made of an organic material.

8. the interlayer insulating layer includes a plurality of insulating films arranged in the second direction corresponding to the plurality of laser waveguides; 2. The multi-beam semiconductor laser device according to claim 1, wherein each insulating film is formed so as to cover an upper portion of the power supply electrode that does not correspond to the insulating film.

9. a plurality of reinforcing electrodes corresponding to the plurality of pad electrodes; 4. The multi-beam semiconductor laser element according to claim 2, wherein each reinforcing electrode is disposed adjacent to a corresponding pad electrode so as to be connectable to a common electrical connection means for the corresponding pad electrode.

10. a plurality of reinforcing electrodes corresponding to the plurality of pad electrodes; 4. The multi-beam semiconductor laser element according to claim 2, wherein each reinforcing electrode has a shape surrounding a corresponding pad electrode so as to be connectable to a common electrical connection means for the corresponding pad electrode.

11. When the number of the laser waveguides is n and the pitch of the laser waveguides is P, the chip width Wchip of the multi-beam semiconductor laser element is expressed as follows: Wchip<100μm+n×P 4. The multi-beam semiconductor laser device according to claim 1, wherein the following relationship is satisfied:

12. The multi-beam semiconductor laser element can be mounted in a junction-up manner, 4. The multi-beam semiconductor laser element according to claim 1, wherein a bonding wire serving as the electrical connection means can be connected to at least one of the pad electrodes of the multi-beam semiconductor laser element.

13. When the distance between the laser waveguides is D and the wire diameter of the bonding wire is φ, D < φ 13. The multi-beam semiconductor laser device according to claim 12, wherein the relationship is satisfied and D≦25 μm.

14. a back surface electrode formed on a surface of the semiconductor substrate opposite to a surface on which the power supply electrode is formed and connectable to a submount of a CAN package; 4. A multi-beam semiconductor laser element according to claim 1, wherein each of the plurality of pad electrodes is connectable to a corresponding lead pin of the CAN package via a bonding wire which is the electrical connection means.

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