Multibeam semiconductor laser device

Abstract

To provide a multi-beam semiconductor laser device with improved yield.SOLUTION: A multi-beam semiconductor laser device 200 includes a first semiconductor laser chip 100_1 and a second semiconductor laser chip 100_2, the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 being supported adjacent to each other in a first direction. In the first semiconductor laser chip 100_1, m laser resonators 140 (m≥1) extending in a second direction perpendicular to the first direction are formed. In the second semiconductor laser chip 100_2, n laser resonators 140 (n≥1) extending in the second direction are formed. The m laser resonators 140 of the first semiconductor laser chip 100_1 are arranged while being biased toward the second semiconductor laser chip 100_2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to a multi-beam semiconductor laser system. [Background technology]

[0002] As a high-power edge-emitting laser, a multi-beam semiconductor laser in which multiple ridge-stripe type laser resonators are monolithically integrated has been proposed (Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2010-245207 [Patent Document 2] Japanese Patent Publication No. 2000-323779 [Overview of the project] [Problems that the invention aims to solve]

[0004] The present inventors, after examining the multi-beam semiconductor laser described in Patent Document 1, have come to recognize the following problems.

[0005] As disclosed in Patent Document 1, we will examine the overall yield of a chip when multiple laser resonators are formed on a single chip. When the yield per laser resonator is Y (Y ≤ 1), the yield of a chip on which n laser resonators are formed is Y n Therefore, as the number of beams n increases, the decrease becomes exponential.

[0006] Some aspects of this disclosure were made in such circumstances, and one exemplary objective is to provide a multi-beam semiconductor laser apparatus with improved yield. [Means for solving the problem]

[0007] Aspects of this disclosure relate to a multi-beam semiconductor laser apparatus. The multi-beam semiconductor laser apparatus comprises a first end-emitting semiconductor laser chip and a second end-emitting semiconductor laser chip, the first and second semiconductor laser chips being supported adjacent to each other in a first direction. Each of the first and second semiconductor laser chips includes a semiconductor substrate and a laminated growth layer formed on the semiconductor substrate, comprising a first conductivity type cladding layer, an emission layer, and a second conductivity type cladding layer. The first semiconductor laser chip has m (m≧1) laser resonators extending in a second direction orthogonal to the first direction, and the second semiconductor laser chip has n (n≧1) laser resonators extending in the second direction. The m laser resonators of the first semiconductor laser chip are arranged biased toward the second semiconductor laser chip side.

[0008] 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]

[0009] According to certain aspects of this disclosure, yield can be improved. [Brief explanation of the drawing]

[0010] [Figure 1] This is a cross-sectional view of a multi-beam semiconductor laser apparatus according to an embodiment. [Figure 2] This is a cross-sectional view showing an example of the configuration of a semiconductor laser chip. [Figure 3] This is a cross-sectional view of a multi-beam semiconductor laser device related to comparative technology. [Figure 4] This figure shows the bonding between the first semiconductor laser chip and the submount in the multi-beam semiconductor laser system shown in Figure 1. [Figure 5]It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 1. [Figure 6] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 2. [Figure 7] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 3. [Figure 8] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 4. [Figure 9] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 5. [Figure 10] It is a diagram showing the bonding of the first semiconductor laser chip and the submount in the multi-beam semiconductor laser device of FIG. 9. [Figure 11] It is a diagram showing another bonding of the first semiconductor laser chip and the submount in the multi-beam semiconductor laser device of FIG. 9. [Figure 12] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 6. [Figure 13] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 7. [Figure 14] It is a diagram showing an example of the bonding of the first semiconductor laser chip and the submount in the multi-beam semiconductor laser device of FIG. 13. [Figure 15] It is a diagram showing another bonding of the first semiconductor laser chip and the submount in the multi-beam semiconductor laser device of FIG. 13. [Figure 16] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 8. [Figure 17] It is a diagram showing another bonding of the first semiconductor laser chip and the submount in the multi-beam semiconductor laser device of FIG. 16. [Figure 18] It is a cross-sectional view of a multi-beam semiconductor laser device according to Embodiment 9.

Mode for Carrying Out the Invention

[0011] (Outline 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.

[0012] A multi-beam semiconductor laser apparatus according to one embodiment comprises a first end-emitting semiconductor laser chip and a second end-emitting semiconductor laser chip, the first and second semiconductor laser chips being supported adjacent to each other in a first direction. Each of the first and second semiconductor laser chips includes a semiconductor substrate and a laminated growth layer formed on the semiconductor substrate, comprising a first conductivity type cladding layer, an emission layer, and a second conductivity type cladding layer. The first semiconductor laser chip has m (m≧1) laser resonators extending in a second direction orthogonal to the first direction, and the second semiconductor laser chip has n (n≧1) laser resonators extending in the second direction. The m laser resonators of the first semiconductor laser chip are arranged biased toward the second semiconductor laser chip side.

[0013] This configuration allows for improved yield compared to integrating all laser resonators onto a single chip by integrating multiple laser resonators across multiple chips. Furthermore, by positioning the m laser resonators formed on the first semiconductor laser chip closer to the second semiconductor laser chip, an appropriate beam spacing can be achieved in a multi-beam laser.

[0014] In one embodiment, the n laser resonators of the second semiconductor laser chip may be arranged biased toward the first semiconductor laser chip. This makes it possible to achieve an appropriate beam spacing in a multi-beam laser.

[0015] In one embodiment, the first semiconductor laser chip and the second semiconductor laser chip may be mounted in a junction-down configuration relative to the submount.

[0016] In one embodiment, m ≥ 2, and the m laser resonators may be configured to be electrically independently drivable.

[0017] In one embodiment, the semiconductor substrate of the first semiconductor laser chip may be an inclined substrate in which the side surface of the semiconductor substrate is inclined on the second semiconductor laser chip side.

[0018] In one embodiment, the system may further include a single submount supporting a first semiconductor laser chip and a second semiconductor laser chip.

[0019] In one embodiment, when m+n≧3, the (m+n) laser resonators formed on the first semiconductor laser chip and the second semiconductor laser chip may be arranged at substantially equal intervals.

[0020] In one embodiment, at least one of the (m+n) laser resonators formed on the first semiconductor laser chip and the second semiconductor laser chip may have a different oscillation wavelength from at least one other. For example, when used as a light source for an image display device such as a head-mounted display (HMD), if the wavelengths of the multi-beams are the same, image quality degradation such as the generation of interference fringes due to the coherence of the laser light occurs. According to the above embodiment, image quality can be improved by varying the wavelengths. Introducing a wavelength difference into multiple laser resonators formed on the same chip requires additional ingenuity in the process and structure, but by separating the multiple resonators into the first semiconductor laser chip and the second semiconductor laser chip, it becomes easier to introduce a large wavelength difference.

[0021] In one embodiment, the first semiconductor laser chip and the second semiconductor laser chip may be arranged with a gap between them.

[0022] (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.

[0023] 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.

[0024] Figure 1 is a cross-sectional view of a multi-beam semiconductor laser apparatus 200 according to an embodiment. The multi-beam semiconductor laser apparatus 200 comprises a first semiconductor laser chip 100_1, a second semiconductor laser chip 100_2, and a submount 210.

[0025] The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are end-face emitting types, and Figure 1 shows them as viewed from the emitting end face. The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are supported adjacent to each other in the first direction (x direction in the figure). The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are arranged non-contact with a gap g between them.

[0026] The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 each have a laminated structure of a semiconductor substrate 110 and a laminated growth layer 120. The first semiconductor laser chip 100_1 has m (m≧1) laser resonators 140a_1 to 140b_1 formed on it, extending in a second direction (z direction, plane depth direction) perpendicular to a first direction (x direction) within the plane of the chip. In this embodiment, m=2. For the purposes of this explanation, the subscripts a and b are omitted when there is no need to distinguish between laser resonators 140a and 140b within the same chip.

[0027] Similarly, the second semiconductor laser chip 100_2 has n (n≧1) laser resonators 140a_2 to 140b_2 that extend in the second direction (z direction). In this embodiment, n=2.

[0028] The exit end face of each laser resonator 140 becomes the emitter (light-emitting part) 102. In other words, the multi-beam semiconductor laser device 200 as a whole has (m+n) laser resonators 140, and therefore the number of emitters 102 (number of channels) of the multi-beam semiconductor laser device 200 is (m+n).

[0029] Figure 2 is a cross-sectional view showing an example configuration of a semiconductor laser chip 100. The semiconductor laser chip 100 comprises a semiconductor substrate 110 and a laminated growth layer 120. The semiconductor substrate 110 may be GaAs in the case of a red laser, and GaN in the case of a blue or green laser.

[0030] The laminated growth layer 120 includes an n-type cladding layer 122, an emissive layer 124, and a p-type cladding layer 126. A p-type contact layer 128 may be formed on the p-type cladding layer 126, if necessary.

[0031] A P electrode 130 is formed on the upper side of the p-type contact layer 128. An N electrode 132 is also formed on the back surface of the semiconductor substrate 110. Other layers, such as an insulating layer, are formed on top of the laminated growth layer 120, but these are omitted here.

[0032] A waveguide structure for confining light is formed in the laminated growth layer 120, and the cleavage surfaces at both ends of this waveguide structure act as mirrors, forming a laser resonator 140. In this example, two laser resonators 140a and 140b are formed, and a beam is emitted from the emitter 102 in the y direction. A reflective film with adjusted reflectivity may also be formed on the cleavage surface.

[0033] The waveguide structure can be, for example, a ridge structure. The ridge structure is formed by partially removing the p-type cladding layer 126. The ridge structure is also simply called a ridge or ridge stripe structure. A bank may be formed between adjacent laser resonators 140a and 140b. The waveguide structure can also be an embedded ridge waveguide.

[0034] Alternatively, the waveguide structure may be a CSP (Channeled Substrate Planar) structure in which grooves are formed in the semiconductor substrate 110 along the waveguide, and the thickness of the n-type cladding layer 122 in the groove portion is relatively thicker.

[0035] Ridge structures and CPS structures are waveguide structures that utilize refractive index distributions, but this disclosure is not limited to these, and gain waveguide structures that utilize gain distributions may also be used. These structures can be understood as both optical confinement structures and current constriction structures.

[0036] The above is an example of the configuration of the semiconductor laser chip 100.

[0037] Returning to Figure 1, the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are mounted on the submount 210. The submount 210 can use a substrate with excellent heat dissipation properties, and a ceramic substrate such as aluminum nitride (AlN) is preferred.

[0038] In this embodiment, the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are mounted in a junction-down configuration relative to the submount 210. The laminated growth layer 120 of the semiconductor laser chip 100 is mounted facing the submount 210, and specifically, the P electrode 130 is electrically connected to the wiring pattern on the submount 210 by solder. Electrode 134 is provided primarily to reinforce the mechanical connection and is connected to the submount 210 by solder.

[0039] The junction-down mounting has the advantage of high cooling efficiency because the heat-generating laser resonator 140 is closer to the submount 210.

[0040] The m laser resonators 140a_1 to 140b_1 of the first semiconductor laser chip 100_1 are arranged biased toward the second semiconductor laser chip 100_2 side. The n laser resonators 140a_2 and 140b_2 of the second semiconductor laser chip 100_2 are arranged biased toward the first semiconductor laser chip 100_1 side.

[0041] Preferably, (m+n) laser resonators 140 are arranged at equal intervals. Typically, the spacing d between the laser resonators 140 can be on the order of 30 μm to 100 μm. Also, the x-direction gap g between adjacent first semiconductor laser chips 100_1 and second semiconductor laser chips 100_2 can typically be on the order of 5 μm to 10 μm. Then, the distance Δx from the side of the first semiconductor laser chip 100_1 to the center of laser resonator 140b_1, and the distance Δx from the side of the second semiconductor laser chip 100_2 to the center of laser resonator 140b_2 are: Δx = (dg) / 2 As a result, Δx will be on the order of 10 μm to 47.5 μm.

[0042] The above is the configuration of the multi-beam semiconductor laser device 200. The advantages of the multi-beam semiconductor laser device 200 will become clear by comparison with the comparative technology. FIG. 3 is a cross-sectional view of the multi-beam semiconductor laser device 200R according to the comparative technology.

[0043] The multi-beam semiconductor laser device 200R includes one semiconductor laser chip 100R. (m + n), that is, four laser resonators 140a to 140d are formed in one semiconductor laser chip 100R.

[0044] Examine the yield of the multi-beam semiconductor laser device 200R according to the comparative technology. Assume that the yield per laser resonator 140 is Y. At this time, the probability that the semiconductor laser chip 100R is a good product is Y (m+n) That is, when P semiconductor laser chips 100R are manufactured, the number of good products is P × Y (m+n) That's it.

[0045] Next, examine the yield of the multi-beam semiconductor laser device 200 according to the embodiment. The probability that the first semiconductor laser chip 100_1 is a good product is Y m Yes, when P first semiconductor laser chips 100_1 are manufactured, the number of good products is P × Y m Similarly, the probability that the second semiconductor laser chip 100_2 is a good product is Y n Yes, when P second semiconductor laser chips 100_2 are manufactured, the number of good products is P × Y n For ease of understanding, if m = n, the number of good products of each of the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 is P × Y m That is, the number of good products of the multi-beam semiconductor laser device 200 is also P × Y m That's it.

[0046] The number of good products of the multi-beam semiconductor laser device 200R obtained in the comparative technology is P × Y 2m On the other hand, the number of good products of the multi-beam semiconductor laser device 200 obtained in the embodiment is P × Ym This is the result. When Y < 1, Y 2m <Y m Therefore, P x Y 2m <P×Y m In other words, the semiconductor laser chip 100 according to this embodiment can improve yield compared to the comparative technology.

[0047] Figure 4 shows the junction between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200 shown in Figure 1. The second semiconductor laser chip 100_2 is the same as the first semiconductor laser chip 100_1, so its illustration and description are omitted. As described above, the first semiconductor laser chip 100_1 is mounted to the submount 210 via a junction-down mounting.

[0048] The surface of the p-type cladding layer 126 is covered with an insulating layer 136. The insulating layer 136 is open at the convex portions of the ridges of the laser resonators 140a_1 and 140b_1, and a P-electrode 130 is formed so as to be in contact with the p-type cladding layer 126. For example, the P-electrode 130 may include a base layer 130a formed by vapor deposition and a thick film layer 130b formed by plating. A P-type contact layer (not shown) is also formed between the p-type cladding layer 126 and the P-electrode 130.

[0049] A metal land (also called a submount electrode) 212 is formed on the surface of the submount 210. Pattern wiring (not shown) is drawn out from the land 212, allowing for external power supply. The P electrode 130 and electrode 134 of the semiconductor laser chip 100 are electrically and mechanically connected to the corresponding land 212 by solder 220, respectively.

[0050] The wide electrode 134, provided separately from the P electrode 130, is electrically insulated from the P electrode 130 of the laser resonators 140a_1 and 140b_1. Therefore, the electrode 134 primarily plays a role in increasing the bonding strength. This configuration makes it possible to reduce the mounting stress generated in each of the multiple laser resonators 140.

[0051] This disclosure covers a variety of apparatuses and methods as seen in Figure 1 or 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.

[0052] Next, we will describe some examples of the multi-beam semiconductor laser apparatus 200.

[0053] (Example 1) Figure 5 is a cross-sectional view of a multi-beam semiconductor laser apparatus 200A according to Embodiment 1. In the multi-beam semiconductor laser apparatus 200A, the semiconductor substrate 110 is an inclined substrate with inclined sides, and has a first side surface S1 that is inclined at an acute angle with respect to the surface S0 facing the submount 210, and a second side surface S2 that is inclined at an obtuse angle.

[0054] The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are arranged so that their acutely inclined first sides S1 are adjacent to each other, and in each semiconductor laser chip 100, the laser resonator 140 is positioned biased toward the acutely inclined first side S1, in other words, offset.

[0055] (Example 2) Figure 6 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200B according to Embodiment 2. In the multi-beam semiconductor laser apparatus 200B, the semiconductor substrate 110 is also an angled substrate. The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are arranged such that a first side surface S1 that is inclined at an acute angle and a second side surface S2 that is inclined at an obtuse angle are adjacent to each other. In the first semiconductor laser chip 100_1, the laser resonator 140_1 is positioned biased toward the acute first side surface S1, and in the second semiconductor laser chip 100_2, the laser resonator 140_2 is positioned biased toward the obtuse second side surface S2.

[0056] (Example 3) Figure 7 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200C according to Embodiment 3. In the multi-beam semiconductor laser apparatus 200C, the semiconductor substrate 110 is also an angled substrate. The first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2 are arranged so that their obtuse-angled second sides S2 are adjacent to each other. In the first semiconductor laser chip 100_1, the laser resonator 140_1 is positioned biased toward the obtuse-angled second side S2, and in the second semiconductor laser chip 100_2, the laser resonator 140_2 is positioned biased toward the obtuse-angled second side S2.

[0057] (Example 4) Figure 8 is a cross-sectional view of a multi-beam semiconductor laser apparatus 200D according to Example 4. In the multi-beam semiconductor laser apparatus 200D, the semiconductor substrate 110 includes a crystal defect cluster region 112. A method for manufacturing a semiconductor substrate having a crystal defect cluster region (core) is disclosed in Japanese Patent No. 3801125. In this technique, a pattern (e.g., SiO2) is intentionally applied to a different type of substrate such as GaAs, and a GaN substrate is grown on it (thick film growth). The patterned area has a 180° inversion of the C axis, the growth rate slows down, and depressions are created. Dislocations propagate to the bottom of the depressions and accumulate there. This technique utilizes this phenomenon to collect dislocations in the core and create a region with a low dislocation density in the other areas.

[0058] For semiconductor lasers, a core line is a linear arrangement of crystal defect cluster regions (cores), and devices cannot be formed on these core lines. An example of dimensions is a core width of approximately 40 μm and a core period of approximately 400 μm. When using a semiconductor substrate 110 having crystal defect cluster regions 112, it is difficult to form many laser resonators 140 side by side on a single semiconductor substrate 110. Therefore, by using the technology according to the embodiment, multiple laser resonators 140 can be formed on two semiconductor laser chips 100_1 and 110_2, making it possible to provide a multi-beam semiconductor laser device 200D equipped with a multi-channel emitter even when using a semiconductor substrate 110 having crystal defect cluster regions 112.

[0059] (Example 5) Figure 9 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200E according to Example 5. In the multi-beam semiconductor laser apparatus 200E, m=2 and n=2. In the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2, the P electrodes 130E of the outer laser resonators 140a_1 and 140a_2 extend toward the outer edge of the chip, which helps to increase the mechanical bonding strength by solder. This P electrode 130E can be understood as being formed continuously from the P electrode 130 and electrode 134 of the outer laser resonator 140a_1 (140a_2) in each semiconductor laser chip 100_1 (100_2) in Figure 1.

[0060] Figure 10 shows the bonding between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200E shown in Figure 9.

[0061] A metal land 212 is formed on the surface of the submount 210. Pattern wiring is drawn from the land 212, allowing for external power supply. The P electrode 130 and P electrode 130E of the semiconductor laser chip 100 are electrically and mechanically connected to the corresponding land 212 by solder 220.

[0062] Figure 11 shows another junction between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200E shown in Figure 9.

[0063] In Figure 11, the P electrodes 130 and 130E each have a two-stage electrode structure including a post (second-stage thick film layer) 130c. Each P electrode 130 and 130E is connected at post 130c by solder 220. Focusing on the P electrode 130E, post 130c is formed to avoid the laser resonator 140a_1. Therefore, the stress on the laser resonator 140a_1 can be further reduced. Also, focusing on the P electrode 130, the plastic deformation of post 130c can further reduce the stress on posts 130a, 130a and the laser resonator 140b_1.

[0064] (Example 6) Figure 12 is a cross-sectional view of a multi-beam semiconductor laser apparatus 200F according to Example 6. In the multi-beam semiconductor laser apparatus 200F, m=2 and n=2. In the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2, the P electrodes 130F of the two laser resonators 140 are formed electrically continuously. This P electrode 130F corresponds to the P electrode 130 and electrode 134 of the two laser resonators 140 formed continuously in each semiconductor laser chip 100 in Figure 1.

[0065] The configuration of Example 6 is effective when it is not necessary to independently control the multiple laser resonators 140 formed on a single chip.

[0066] (Example 7) Figure 13 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200G according to Example 7. In the multi-beam semiconductor laser apparatus 200G, m=1, n=1, and one laser resonator 140_1, 140_2 is formed on the first semiconductor laser chip 100_1 and the second semiconductor laser chip 100_2, respectively. The P electrode 130G is wide in the x direction, and therefore the mechanical bonding strength by solder is increased.

[0067] Figure 14 shows an example of bonding between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200G shown in Figure 13. In Figure 14, the P electrode 130G is connected to the land 212 by solder 220.

[0068] Figure 15 shows another junction between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200G shown in Figure 13. In Figure 15, the P electrode 130G is a two-stage electrode, and the post 130c is formed in a region that does not overlap with the laser resonator 140. This reduces the mounting stress generated in the laser resonator 140_1 compared to the configuration in Figure 14.

[0069] (Example 8) Figure 16 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200H according to Example 8. In the multi-beam semiconductor laser apparatus 200H, m=1 and n=1, similar to Example 7. The difference from Figure 13 is that the P electrode 130 is separated from the electrode 134.

[0070] In Examples 7 and 8, a configuration in which the semiconductor substrate 110 is a tilted substrate is also valid as an embodiment of this disclosure.

[0071] Figure 17 shows another junction between the first semiconductor laser chip 100_1 and the submount 210 in the multi-beam semiconductor laser apparatus 200H of Figure 16. In this configuration, the P electrode 130 and electrode 134 are mounted on a common land 212.

[0072] (Example 9) Figure 18 is a cross-sectional view of the multi-beam semiconductor laser apparatus 200I according to Example 9. The first semiconductor laser chip 100_1 includes m laser resonators 140_1 in addition to a dummy resonator 142_1. The second semiconductor laser chip 100_2 includes n laser resonators 140_2 in addition to a dummy resonator 142_2. In this example, m=n=2. The dummy resonator 142 has a waveguide structure (ridge structure) similar to that of the laser resonator 140, but does not oscillate and therefore does not emit a beam. Thus, the multi-beam semiconductor laser apparatus 200I in Figure 13 is a multi-beam laser with m+n=4 channels.

[0073] (modified version) In the embodiment, the case where m=n was described, but this is not limited to cases where m≠n. For example, m=1 and n=2.

[0074] In this embodiment, a multi-beam semiconductor laser device 200 comprising two semiconductor laser chips 100 has been described, but the number of semiconductor laser chips 100 may be three or more.

[0075] 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]

[0076] 100 semiconductor laser chips 100_1 First Semiconductor Laser Chip 100_2 Second Semiconductor Laser Chip 102 Emitter 110 Semiconductor substrates 120 Stacked Growth Layers 122 n-type cladding layer 124 Emitting layer 126 p-type cladding layer 128 p-type contact layer 130P electrode 132 N electrode 134 Electrode 140 Laser resonators 200 Multibeam Semiconductor Laser System 210 Submount 212 Land

Claims

1. A multi-beam semiconductor laser device, A first semiconductor laser chip with end-face emission, A second semiconductor laser chip with end-face emission, The first semiconductor laser chip and the second semiconductor laser chip are supported adjacent to each other in the first direction, The first semiconductor laser chip and the second semiconductor laser chip are, Semiconductor substrate and A laminated growth layer comprising a first conductivity type cladding layer, an emissive layer, and a second conductivity type cladding layer formed on the semiconductor substrate, It has, The first semiconductor laser chip has m (m≧2) laser resonators formed therein, extending in a second direction perpendicular to the first direction. The second semiconductor laser chip has n (n≧1) laser resonators extending in the second direction. A multi-beam semiconductor laser apparatus characterized in that the m laser resonators of the first semiconductor laser chip are arranged biased toward the second semiconductor laser chip side and are configured to be electrically independently drivable.

2. The multi-beam semiconductor laser apparatus according to claim 1, characterized in that the n laser resonators of the second semiconductor laser chip are arranged biased toward the first semiconductor laser chip side.

3. The multi-beam semiconductor laser apparatus according to claim 1 or 2, characterized in that the first semiconductor laser chip and the second semiconductor laser chip are mounted in a junction-down configuration relative to a submount.

4. The multi-beam semiconductor laser apparatus according to claim 1 or 2, characterized in that the semiconductor substrate of the first semiconductor laser chip is an inclined substrate on the side of the second semiconductor laser chip, wherein the side surface of the semiconductor substrate is inclined.

5. The multi-beam semiconductor laser apparatus according to claim 1 or 2, further comprising a single submount supporting the first semiconductor laser chip and the second semiconductor laser chip.

6. The multibeam semiconductor laser apparatus according to claim 1 or 2, characterized in that when m + n ≥ 3, the (m + n) laser resonators formed on the first semiconductor laser chip and the second semiconductor laser chip are arranged at equal intervals.

7. The multibeam semiconductor laser apparatus according to claim 1 or 2, characterized in that at least one of the (m+n) laser resonators formed in the first semiconductor laser chip and the second semiconductor laser chip has an oscillation wavelength different from at least one of the others.

8. The multi-beam semiconductor laser apparatus according to claim 1 or 2, characterized in that the first semiconductor laser chip and the second semiconductor laser chip are arranged with a gap between them.

9. A multi-beam semiconductor laser apparatus, A first semiconductor laser chip with end-face emission, A second semiconductor laser chip with end-face emission, The first semiconductor laser chip and the second semiconductor laser chip are supported adjacent to each other in the first direction, The first semiconductor laser chip and the second semiconductor laser chip are, Semiconductor substrate and A laminated growth layer comprising a first conductivity type cladding layer, an emissive layer, and a second conductivity type cladding layer formed on the semiconductor substrate, It has, The first semiconductor laser chip has m (m≧2) laser resonators formed therein, extending in a second direction perpendicular to the first direction. The second semiconductor laser chip has n (n≧1) laser resonators extending in the second direction. The m laser resonators of the first semiconductor laser chip are arranged biased toward the second semiconductor laser chip side. A multi-beam semiconductor laser apparatus characterized in that, when m + n ≥ 3, the (m + n) laser resonators formed on the first semiconductor laser chip and the second semiconductor laser chip are arranged at equal intervals.

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