Semiconductor laser device and method for manufacturing the same

Abstract

Even with chips that are narrow in width and have a large board tilt angle, this technology suppresses chip tipping and tilted mounting. [Solution] The end-face emitting semiconductor laser chip 100 is mounted on a submount 210. The semiconductor laser chip 100 is provided with an anti-tipping structure 170 at the contact portion with the submount 210 on the first side surface S1, which is one of two side surfaces S1 and S2 parallel to the resonator direction (z direction) and has an inclination angle greater than 90 degrees.

Description

Technical Field

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

Background Art

[0002] Conventionally, as an end-emitting semiconductor laser (LD: Laser Diode), generally GaAs substrates, InP substrates, GaN substrates, Si substrates, etc. have been used. A semiconductor laser has the characteristic that as the operating temperature rises, the threshold current increases and the light emission efficiency decreases. This is due to the phenomenon (carrier overflow) in which electrons in the high-energy state overflow from the active layer to the cladding layer as the temperature rises. In order to improve the increase in the threshold current and the decrease in the light emission efficiency accompanying this temperature rise, a measure of increasing the difference ΔEc in the Fermi level between the active layer and the cladding layer by increasing the carrier concentration in the P-type cladding layer and lowering the Fermi level is effective. (Non-Patent Document 1).

[0003] In the case of a red semiconductor laser, an AlGaInP-based crystal is grown on a GaAs substrate using a method such as metal organic chemical vapor deposition (MOCVD).

[0004] When AlGaInP is grown on a substrate crystal having a main surface inclined in a certain direction of the plane orientation, the formation of a natural superlattice is suppressed, and it is known that a crystal with a large bandgap energy can be obtained even with the same composition. Patent Document 1 and Non-Patent Document 1 disclose a semiconductor laser element using an inclined substrate (tilted substrate) in which the plane orientation of a GaAs substrate is inclined by about 5° to 15° from the (100) plane to the

[0011] direction. By increasing the tilt angle (off angle) of the plane orientation of the GaAs substrate, the adsorption probability of atoms of P-type impurities to the step edge of the epitaxial layer increases, and the dopant efficiency increases, so that a high P-type carrier concentration in the cladding layer can be obtained.

[0005] By increasing the off-angle of the semiconductor substrate in this way, a high P-type carrier concentration can be obtained, reducing the series resistance and increasing the ΔEc of the active layer and cladding layer. This results in a high-power laser with less heat generation due to resistance and less electron overflow.

[0006] In recent years, there has been a demand for higher power output in semiconductor lasers, and the off-angle of semiconductor substrates has been gradually increasing. On the other hand, regarding the chip width of LDs, the development and commercialization of packages (multi-die packages) that allow multiple LD chips to be densely arranged to obtain high optical output from a narrow area are progressing. For this reason, there is also a demand to reduce the size of LD chips, that is, to narrow the chip width.

[0007] Furthermore, from a cost perspective, narrowing the chip width increases the number of chips that can be obtained from a single wafer, resulting in cost reduction.

[0008] Therefore, there is a demand for semiconductor substrates with large off-angles and narrow chip widths. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2017-59620 [Non-patent literature]

[0010] [Non-Patent Document 1] Isamu Akasaki, "III-V Group Compound Semiconductors", pp. 311-312, 320, May 1, 1994, Baifusha [Overview of the project] [Problems that the invention aims to solve]

[0011] However, when using chips with a large off-angle and narrow chip width, the chip's center of gravity is significantly offset from the center of the mounting surface on the submount. As a result, when mounting the chip on the submount, it may tip over or be mounted at an angle. If the chip tips over, the yield decreases, and if the chip is mounted at an angle, the optical axis becomes misaligned and heat dissipation from the submount deteriorates, resulting in degraded performance.

[0012] This disclosure has been made in view of the aforementioned issues, and one exemplary objective of a certain aspect thereof is to provide a semiconductor laser device in which chip tipping and tilting are suppressed, even with chips that have a narrow chip width and a large off-angle. [Means for solving the problem]

[0013] A semiconductor laser apparatus according to one aspect of the present disclosure comprises a submount and an end-face emitting semiconductor laser chip bonded to the submount via a bonding material. The semiconductor laser chip includes a semiconductor substrate which is a tilted substrate having a main surface whose surface orientation is tilted in a certain direction and two side surfaces parallel to the crystal axis; a laminated structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer formed sequentially on the main surface of the semiconductor substrate; a first electrode formed on the side of the semiconductor substrate opposite to the laminated structure; and a second electrode formed on the laminated structure. The semiconductor laser chip has two side surfaces which are tilted with respect to a surface perpendicular to the submount and parallel to the resonator direction, and an anti-tipping structure is provided on the first side surface which has an inclination angle with respect to the main surface greater than 90 degrees.

[0014] Furthermore, any combination of the above components, or any substitution of components or expressions between methods, apparatus, systems, etc., are also valid as embodiments of the present invention or this disclosure. Moreover, the description in this section (means for solving the problem) does not describe all the indispensable features of the present invention, and therefore, subcombinations of these described features may also constitute the present invention. [Effects of the Invention]

[0015] According to certain aspects of the present disclosure, it is possible to suppress the toppling or tilting of the chip during mounting.

Brief Description of the Drawings

[0016] [Figure 1] It is a perspective view of a semiconductor laser device according to an embodiment. [Figure 2] It is a cross-sectional view of the semiconductor laser device of FIG. 1 seen along the resonator direction (z direction). [Figure 3] It is a cross-sectional view of the semiconductor laser device. [Figure 4] It is a cross-sectional view of a semiconductor laser chip according to Example 1. [Figure 5] It is a diagram for explaining a method of manufacturing the semiconductor laser chip of FIG. 4. [Figure 6] It is an enlarged cross-sectional view of the anti-tipping structure. [Figure 7] It is a cross-sectional view of a semiconductor laser chip according to Example 2. [Figure 8] It is a cross-sectional view of a semiconductor laser chip according to Example 3. [Figure 9] It is a cross-sectional view of a semiconductor laser chip according to Example 4. [Figure 10] It is a cross-sectional view of a semiconductor laser chip according to Example 5. [Figure 11] It is a diagram for explaining a method of manufacturing the semiconductor laser chip of FIG. 10. [Figure 12] It is a perspective view of a semiconductor laser device including a semiconductor laser chip according to Example 6.

Modes for Carrying Out the Invention

[0017] (Summary of the Embodiment) This section outlines some exemplary embodiments of the present disclosure. This outline serves as a prelude to the detailed description that follows, or as a means of understanding the embodiments. This outline provides a simplified explanation of some concepts of one or more embodiments and does not limit the scope of the invention or disclosure. Furthermore, this outline is not a comprehensive overview of all possible embodiments and does not limit the essential components of the embodiments. For convenience, “one embodiment” may be used to refer to one embodiment (example or variation) or more embodiments (example or variation) disclosed herein.

[0018] A semiconductor laser device according to one embodiment comprises a submount and an end-face emitting semiconductor laser chip bonded to the submount via a bonding material. The semiconductor laser chip is a tilted substrate having a main surface whose surface orientation is tilted in a certain direction and two side surfaces parallel to the crystal axis, wherein the two side surfaces are tilted with respect to a plane perpendicular to the submount and parallel to the resonator direction, a laminated structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer formed sequentially on the semiconductor substrate, a first electrode formed on the side of the semiconductor substrate opposite to the laminated structure, and a second electrode formed on the laminated structure. The semiconductor laser chip has two side surfaces tilted with respect to a plane perpendicular to the submount and parallel to the resonator direction, and an anti-tipping structure is provided on the first side surface, which is one of the two side surfaces and has an inclination angle with respect to the main surface greater than 90 degrees.

[0019] By increasing the off-angle of the tilted substrate, a high P-type carrier concentration can be obtained, reducing the series resistance and increasing the ΔEc between the active layer and the cladding layer. This results in a high-power laser with less heat generation due to resistance and less electron overflow.

[0020] This configuration allows the mounting surface of the chip to be positioned closer to the chip's center of gravity by incorporating an anti-tipping structure. This helps to suppress tilting and tipping when mounting the chip onto the submount.

[0021] In one embodiment, the off-angle of the inclined substrate may be 10 degrees or more. Preferably, it may be 15 degrees or more, which provides an effect of further suppressing tilting and tipping.

[0022] In one embodiment, the inclination angle of the anti-tipping structure, that is, the angle between the inclined surface of the anti-tipping structure and the reference surface, may be less than 90 degrees. This makes it less likely to tip over.

[0023] In one embodiment, when the direction perpendicular to both the resonator direction and the stacking direction of the stacked structure is defined as the chip width direction, the ratio of the length in the stacking direction of the semiconductor laser chip to the length in the chip width direction of the semiconductor laser chip may be 0.5 or more.

[0024] In one embodiment, the length in the width direction of the chip may be 200 μm or less.

[0025] In one embodiment, the semiconductor laser chip may further have a notch structure paired with the anti-tipping structure on a second side, which is the other of two sides parallel to the resonator direction. This allows the anti-tipping structure to be formed on the cleavage surface during the process of cleaving and separating the chip that will become the semiconductor laser chip from the semiconductor wafer. As a further effect, since the second side is notched toward the center of the chip, unintended chipping and cracking can be prevented.

[0026] In one embodiment, the anti-tipping structure may be provided continuously between the output end face of the semiconductor laser chip and the rear end face on the opposite side.

[0027] In one embodiment, the anti-tipping structure may be provided separately at two locations: on the exit end face side of the semiconductor laser chip and on the opposite rear end face side. Alternatively, the anti-tipping structure may be provided at least one or more locations in the direction of the resonator.

[0028] In one embodiment, the semiconductor laser chip may be a junction-down type, where the stacked structure side is the mounting surface with the submount. The anti-tipping structure may be provided on the stacked structure side of the first side surface. Since the substrate and the stacked structure formed by epitaxial growth are made of different materials, the anti-tipping structure can be easily formed during the cleavage process.

[0029] In one embodiment, the height of the anti-tipping structure in the stacking direction may be greater than the thickness of the stacked structure. This ensures that the inflection point of the first side surface is located within the substrate, thus preventing cracks from forming in the stacked structure during the cleavage process. Furthermore, if the inflection point is located within the stacked structure, light guiding the stacked structure will radiate from the inflection point, resulting in stray light. However, by having the inflection point located within the substrate, stray light can be suppressed.

[0030] In one embodiment, the second electrode may cover at least a portion of the anti-tipping structure. The second electrode has higher ductility compared to the laminated structure or substrate, and is therefore less susceptible to cleavage. By having a portion of the anti-tipping structure covered by a metal layer and the remaining portion having the second conductive semiconductor layer exposed, the region other than the metal layer can be used as a guide for cleavage, making it easy to form the anti-tipping structure.

[0031] In one embodiment, the second electrode does not need to cover the anti-tipping structure.

[0032] In one embodiment, the second conductive semiconductor layer has a ridge portion and a bank adjacent thereto, and the bank may extend to at least a part of the anti-tipping structure.

[0033] In one embodiment, the anti-tipping structure may have a step on the mounting surface with respect to the submount. This step may be a pelletizing groove in the cleavage process.

[0034] One embodiment relates to a method for manufacturing any of the semiconductor laser devices described above. The manufacturing method includes the steps of: forming a laminated structure by sequentially epitaxially growing a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer on a semiconductor wafer corresponding to a semiconductor substrate; forming ridges in the laminated structure; forming a second electrode on the laminated structure; forming the first electrode on the side of the semiconductor substrate opposite to the laminated structure; and cleaving and separating a semiconductor laser chip from the semiconductor wafer. The cleaving and separation step includes the step of forming an anti-tipping structure by adjusting the position to which a cleaving jig is pressed.

[0035] (Embodiment) The present disclosure will be described below with reference to the drawings, based on preferred embodiments. The same or equivalent components, members, and processes shown in each drawing will be denoted by the same reference numerals, and redundant descriptions will be omitted where appropriate. Furthermore, the embodiments are illustrative and not limiting, and not all features or combinations thereof described in the embodiments are necessarily essential to the disclosure.

[0036] The dimensions (thickness, length, width, etc.) of each component shown in the drawing 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 component A is depicted as thicker than component B in the drawing, component A may actually be thinner than component B.

[0037] Figure 1 is a perspective view of a semiconductor laser apparatus 200 according to an embodiment. The semiconductor laser apparatus 200 comprises an end-face emitting type semiconductor laser chip 100 and a submount 210. The semiconductor laser chip 100 is bonded to the submount 210 via a bonding material 220. The semiconductor laser chip 100 is an oblique angle prism having an emission end face (also called a front end face) Sf, a rear end face Sr, and side surfaces S1 and S2. The front end face Sf and the rear end face Sr are perpendicular to the submount 210, but the side surfaces S1 and S2 are inclined from the surface of the submount 210 and a plane (yz plane) perpendicular to the front end face Sf and the rear end face Sr.

[0038] The submount 210 is appropriately selected considering factors such as heat dissipation, insulation, the difference in coefficient of thermal expansion with the semiconductor laser chip, and cost. For example, insulating materials with good heat dissipation include aluminum nitride (AlN), silicon carbide (SiC), diamond (C), and silicon nitride (SiN); conductive materials include copper (Cu), copper tungsten (CuW), and copper molybdenum (CuMo); and relatively inexpensive materials include silicon (Si) and aluminum oxide (Al2O3). The submount 210 may also be composed of a multilayer structure combining insulating materials such as AlN and SiC with conductive materials such as copper (Cu), gold (Au), and gold-tin (AuSn).

[0039] The bonding material 142 may be solder materials such as gold-tin (AuSn), tin-silver-copper (SnAgCu), tin-silver (SnAg), or tin-gold (SnAu), as well as low-melting-point metal materials such as indium (In) or silver (Ag) paste, or sintered materials such as silver (Ag) nanopaste or gold (Au) nanopaste.

[0040] In the drawings referenced herein, the direction of optical guidance is taken as the z-axis, and this is also referred to as the resonator direction. The y-axis is taken perpendicular to the plane of the submount 210, and this is also referred to as the stacking direction. The x-axis, which is perpendicular to the z-axis and y-axis, is also referred to as the chip width direction.

[0041] Figure 2 is a cross-sectional view of the semiconductor laser apparatus 200 shown in Figure 1, viewed along the resonator direction (z-direction).

[0042] The semiconductor laser chip 100 is mounted on the submount 210 via a bonding material 220. The semiconductor laser chip 100 includes a semiconductor substrate 110, a stacked structure 120 formed on the semiconductor substrate 110, a first electrode 140, and a second electrode 142.

[0043] The semiconductor substrate 110 is a tilted substrate having a main surface 112 whose surface orientation is tilted in a certain direction, and two side surfaces 114 and 116 parallel to the crystal axis. The two side surfaces 114 and 116 are tilted about the z axis with respect to a plane (yz plane) that is perpendicular to the submount 210 and parallel to the resonator direction. The tilt angle ω of the crystal axis with respect to the y axis is 15° or more. The two side surfaces 114 and 116 of the semiconductor substrate 110 form the two side surfaces S1 and S2 of the semiconductor laser chip 100.

[0044] The laminated structure 120 is formed on the main surface 112 of the semiconductor substrate 110. As described later, the laminated structure 120 includes a first conductivity type (n-type) semiconductor layer, an active layer, and a second conductivity type (p-type) semiconductor layer, which are formed in order on top of (below in the paper) the main surface 112 of the semiconductor substrate 110. A ridge structure 130 may be formed in the p-type semiconductor layer as a current constriction structure. Banks 132 may also be formed on both sides of the ridge structure 130. A first (n-type) electrode 140 is formed on the surface of the semiconductor substrate 110 opposite to the main surface 112, and a second (p-type) electrode 142 is formed on top of the laminated structure 120.

[0045] The semiconductor laser device 200 is a junction-down type, and the semiconductor laser chip 100 is mounted in an orientation such that the stacked structure 120 faces the submount 210.

[0046] The semiconductor laser chip 100 is provided with an anti-tipping structure 170 formed to increase the contact area with the submount 210 via a bonding material 220 on the first side surface S1, which is one of two side surfaces S1 and S2 parallel to the resonator direction (z-axis) and has an inclination angle greater than 90 degrees. The inclination angle θ1 (θ2) of the side surface S1 (S2) refers to the angle that the side surface S1 (S2) makes with the main surface 112.

[0047] The anti-tipping structure 170 may have a cross-sectional shape that is approximately triangular when viewed from the direction of the resonator of the semiconductor laser chip 100.

[0048] In the embodiment shown in Figure 1, the anti-tipping structure 170 is continuously provided along the entire length of the semiconductor laser element 100 between the exit end face Sf of the semiconductor laser chip 100 and the rear end face Sr on the opposite side. Here, the anti-tipping structure 170 is formed in a direction that protrudes from the first side surface S1 toward the main surface 112 of the semiconductor substrate 110, or toward the extension of the mounting surface (the surface mounted on the submount 210 via the bonding material 220).

[0049] On the second side S2 opposite to the first side S1, a notch structure 180 may be provided at the contact portion with the submount 210. This notch structure 180 has a shape that fits in conjunction with the anti-tipping structure 170 of adjacent semiconductor laser chips 100 when the same semiconductor laser chips 100 are lined up.

[0050] The above describes the configuration of the semiconductor laser chip 100. Next, we will explain its advantages with reference to Figure 3.

[0051] Figure 3 is a cross-sectional view of the semiconductor laser device 200. G represents the center of gravity of the semiconductor laser chip 100. When mounting the semiconductor laser chip 100 to the submount 210, a force F is applied to rotate the semiconductor laser chip 100 clockwise in the figure.

[0052] C2 indicates the center position in the chip width direction (x direction) of the mounting surface S3 when the anti-tipping structure 170 and the notch structure 180 are absent. When the anti-tipping structure 170 is absent, the center position C2 is far from the center of gravity G, making the semiconductor laser chip 100 more prone to tipping over clockwise due to the force F.

[0053] C1 indicates the center position in the chip width direction (x direction) of the mounting surface S3 when the anti-tipping structure 170 and the notch structure 180 are provided. By providing the anti-tipping structure 170, the center position C1 moves closer to the center of gravity G, making it less likely for the semiconductor laser chip 100 to tip over clockwise due to the force F.

[0054] Thus, according to this embodiment, tipping over or tilting during the mounting of the semiconductor laser chip 100 (chip) can be suppressed.

[0055] Furthermore, when the ratio of the length in the stacking direction (chip height) H of the semiconductor laser chip 100 to the length in the chip width direction (chip width) W of the semiconductor laser chip 100 shown in Figure 2 is 0.5 or more, the semiconductor laser chip 100 becomes prone to tipping over. Therefore, this disclosure is particularly effective for semiconductor laser chips 100 where H / W ≥ 0.5.

[0056] The chip width W may be 200 μm or less. The narrower the chip width W, the more easily the semiconductor laser chip 100 is prone to tipping over. Therefore, this disclosure is particularly effective for semiconductor laser chips 100 where W ≤ 200 μm.

[0057] Next, we will describe specific examples and variations of the semiconductor laser chip 100.

[0058] This disclosure covers a variety of devices, as understood in the perspective view of Figure 1 and the cross-sectional view of Figure 2, or as derived from the above description, and is not limited to any particular configuration. More specific configuration examples and embodiments are described below, not to narrow the scope of this disclosure, but to aid in understanding and clarifying the essence and operation of this disclosure and the present invention.

[0059] (Example 1) Figure 4 is a cross-sectional view of a semiconductor laser chip 100A according to Embodiment 1. In this embodiment, the semiconductor laser chip 100A comprises a semiconductor substrate 110 and a laminated structure 120 formed on the semiconductor substrate 110. The laminated structure 120 includes a first conductivity type (N-type) semiconductor layer 122, an active layer 124, and a second conductivity type (P-type) semiconductor layer 126.

[0060] A ridge structure 130 may be formed in the P-type semiconductor layer 126 of the stacked structure 120 as a current-constricting structure.

[0061] The semiconductor laser chip 100A is a junction-down type, with the stacked structure 120 side being the mounting surface with the submount 210, and the anti-tipping structure 170A is provided on the stacked structure 120 side of the first side surface S1.

[0062] Figure 5 illustrates the manufacturing method of the semiconductor laser chip 100A shown in Figure 4. First, a laminated structure 902 is formed on a semiconductor wafer 900, which is a semiconductor substrate, by sequentially epitaxially growing an N-type semiconductor layer, an active layer, and a P-type semiconductor layer. Then, a ridge portion 904, which is a current-constricting structure, is formed on the laminated structure 902 (S100). The dashed line 906 indicates the planned cleavage line.

[0063] Next, the semiconductor wafer 900 is cleaved along the planned cleavage line 906 and divided into multiple LD bars 910 (S102).

[0064] Next, a scribing line 914 is drawn on the back surface of the semiconductor wafer 900 using a scribing needle 912 (S104).

[0065] S106 represents the cleavage separation process. The LD bar 910 is placed on the support base 920. The support base 920 has a recess 922 that extends in the direction of the resonator. The LD bar 910 is positioned so that the scribed line 914 is located on the recess 922.

[0066] The tip of the blade 924, which is a cleavage jig, is positioned at a location offset from a virtual line drawn from the scribed line 914 along the inclination direction of the semiconductor substrate of the semiconductor wafer 900, that is, along the direction of the semiconductor crystal axis. If the virtual line connecting the tip of the blade 924 and the scribed line 914 is in a direction that coincides with the crystal axis of the semiconductor substrate, cleavage will occur along the crystal axis. However, by pressing the tip of the blade 924 against a position offset from the virtual line, the cleavage plane that is cleaved along the crystal axis from the scribed line 914 breaks in a way that it chips away towards the tip of the blade 924, forming a bent cleavage line 926.

[0067] The semiconductor laser chip 100A has an anti-tipping structure 170 and a notch structure 180 (S108).

[0068] The above describes the method for manufacturing the semiconductor laser chip 100A. According to this manufacturing method, a semiconductor laser chip 100A having an anti-tipping structure 170 can be easily formed using a cleavage separation process.

[0069] Figure 6 is an enlarged cross-sectional view of the anti-tipping structure 170A. Preferably, the height h of the anti-tipping structure 170A in the stacking direction (y direction) is greater than the thickness t of the stacked structure 120. In this case, the intersection line (inflection point P) of the first side surface S1 of the semiconductor substrate 110 and the inclined surface S5 of the anti-tipping structure 170A is located at the depth of the semiconductor substrate 110, rather than the stacked structure 120. Therefore, it is possible to prevent cracks from forming in the stacked structure 120 when forming the anti-tipping structure 170A during the cleavage process. Furthermore, if the inflection point P is located within the range of the stacked structure 120, light guiding the stacked structure 120 may be emitted from the inflection point, potentially resulting in stray light. In contrast, with the configuration in Figure 6, since the inflection point P is at the depth of the semiconductor substrate 110, stray light can be suppressed.

[0070] The inclination angle φ of the anti-tipping structure 170A, that is, the angle between the inclined surface S5 and the mounting surface S3, is preferably less than 90 degrees. The width w of the mounting surface S3 of the anti-tipping structure 170A is expressed by the following formula. w = h / tanφ + h / tan(180°-θ1)

[0071] In the range φ < 90°, reducing φ increases the h / tanφ term, allowing the width w of the anti-tipping structure 170A to be widened, thereby enhancing the anti-tipping effect.

[0072] (Example 2) Figure 7 is a cross-sectional view of a semiconductor laser chip 100B according to Example 2. The second electrode 142 formed on the stacked structure 120 forms the mounting surface S3, and the second electrode 142 covers at least a portion of the anti-tipping structure 170.

[0073] With this configuration, it is possible to use areas other than the second electrode 142 as a guide for cleavage, in which case the anti-tipping structure 170 can be easily formed.

[0074] (Example 3) Figure 8 is a cross-sectional view of a semiconductor laser chip 100F according to Example 3. The second electrode 142 formed on the stacked structure 120 forms the mounting surface S3, and the second electrode 142 does not cover the anti-tipping structure 170.

[0075] This configuration makes it possible to suppress tilting or tipping of the semiconductor laser chip 100F when mounting the semiconductor laser chip 100F to the submount via a bonding material.

[0076] (Example 4) Figure 9 is a cross-sectional view of the semiconductor laser chip 100C according to Embodiment 4. The semiconductor laser chip 100C has a ridge structure 130 formed on top of a stacked structure 120. A bank 132 is formed adjacent to the ridge structure 130.

[0077] With respect to the width direction (x direction), the bank 132 is formed to extend to at least a portion of the anti-tipping structure 170.

[0078] (Example 5) Figure 10 is a cross-sectional view of a semiconductor laser chip 100D according to Embodiment 5. In this embodiment, the anti-tipping structure 170D has a step 172 on the mounting surface S3. A step 182 is also formed on the notched structure 180 side.

[0079] Figure 11 illustrates the manufacturing method of the semiconductor laser chip 100D shown in Figure 10. Prior to the cleavage separation process, the LD bar 910D has pelletizing grooves 930 formed at the positions where the blade 924 should be applied. By pressing the blade 924 against the pelletizing grooves 930, the semiconductor laser chip 100D is cut out along the bent cleavage line 926. The pelletizing grooves 930 result in steps 172 and 182 in Figure 10.

[0080] (Example 6) Figure 12 is a perspective view of a semiconductor laser device 200E equipped with a semiconductor laser chip 100E according to Embodiment 6. In this embodiment, the anti-tipping structure 170E is provided separately at two locations: on the exit end face Sf side and on the opposite rear end face Sr side.

[0081] Although the embodiments described a junction-down type semiconductor laser chip, this disclosure is also applicable to a junction-up type semiconductor laser chip. In this case, the semiconductor laser chip 100 shown in Figure 1 has the semiconductor substrate 110 side (first electrode 140 side) as the bonding surface with the submount, rather than the stacked structure 120, and the anti-tipping structure 170 is formed on the semiconductor substrate 110.

[0082] The embodiments merely illustrate the principles and applications of the present invention, and many modifications and changes in arrangement are permitted in the embodiments, without departing from the spirit of the present invention as defined in the claims. [Explanation of symbols]

[0083] 100 semiconductor laser chips 102 Laser resonator 110 Semiconductor substrates 120 Laminated structure 122 N-type semiconductor layer 124 Active layer 126 P-type semiconductor layer 130 Ridge structure 200 Semiconductor laser devices 210 Submount

Claims

1. Submount and An end-face emitting semiconductor laser chip bonded to a submount via a bonding material, Equipped with, The aforementioned semiconductor laser chip is A semiconductor substrate which is a tilted substrate having a main surface whose surface orientation is tilted in a certain direction and two side surfaces parallel to the crystal axis, A laminated structure comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer formed sequentially on the main surface of the semiconductor substrate, A first electrode formed on the semiconductor substrate opposite to the laminated structure, A second electrode formed on the aforementioned laminated structure, Includes, A semiconductor laser device characterized in that a tipping prevention structure is provided on the first side surface of the semiconductor laser chip, which is one of two side surfaces parallel to the resonator direction and has an inclination angle with the main surface greater than 90 degrees.

2. The semiconductor laser apparatus according to claim 1, characterized in that the off-angle of the semiconductor substrate is 10 degrees or more.

3. The semiconductor laser apparatus according to claim 1, characterized in that the inclination angle of the aforementioned anti-tipping structure is less than 90 degrees.

4. The semiconductor laser apparatus according to claim 1, characterized in that, when the direction perpendicular to both the resonator direction and the stacking direction of the stacked structure is defined as the chip width direction, the ratio of the length of the semiconductor laser chip in the stacking direction to the length of the semiconductor laser chip in the chip width direction is 0.5 or more.

5. The semiconductor laser apparatus according to claim 4, characterized in that the length of the semiconductor laser chip in the chip width direction is 200 μm or less.

6. The semiconductor laser device according to any one of claims 1 to 5, wherein the semiconductor laser chip further comprises a notch structure on the second side, which is the other of the two sides, that is paired with the anti-tipping structure.

7. The semiconductor laser apparatus according to any one of claims 1 to 5, characterized in that the anti-tipping structure is provided continuously between the output end face of the semiconductor laser chip and the rear end face on the opposite side.

8. The semiconductor laser apparatus according to any one of claims 1 to 5, characterized in that the anti-tipping structure is provided separately at two locations: on the exit end face side of the semiconductor laser chip and on the rear end face side opposite to it.

9. The semiconductor laser chip is a junction-down type, where the stacked structure side is the mounting surface with the submount. The semiconductor laser apparatus according to any one of claims 1 to 5, characterized in that the anti-tipping structure is provided on the laminated structure side of the first side surface.

10. The semiconductor laser apparatus according to claim 9, characterized in that the height of the anti-tipping structure in the stacking direction of the stacked structure is greater than the thickness of the stacked structure.

11. The semiconductor laser apparatus according to claim 9, characterized in that the second electrode covers at least a part of the anti-tipping structure.

12. The semiconductor laser apparatus according to claim 9, characterized in that the second electrode does not cover the anti-tipping structure.

13. The second conductive semiconductor layer has a ridge portion and an adjacent bank portion formed therein. The semiconductor laser apparatus according to claim 9, characterized in that the bank extends to at least a part of the anti-tipping structure.

14. The semiconductor laser apparatus according to claim 9, characterized in that the anti-tipping structure has a step on the mounting surface side with respect to the submount.

15. A method for manufacturing a semiconductor laser apparatus according to any one of claims 1 to 3, The process of forming the laminated structure by sequentially epitaxially growing the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer on a semiconductor wafer corresponding to the semiconductor substrate, The aforementioned laminated structure includes the step of forming a ridge portion, A step of forming the second electrode on the laminated structure, A step of forming a first electrode on the semiconductor substrate on the side opposite to the laminated structure, A step of cleaving and separating a semiconductor laser chip from the semiconductor wafer, It has, The manufacturing method is characterized in that the cleavage separation step includes a step of forming the tipping prevention structure by adjusting the position against which the cleavage jig is pressed.

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