Multi-beam semiconductor laser element

Abstract

To provide a semiconductor laser element in which deterioration of reliability in a coating step is suppressed.SOLUTION: A plurality of laser waveguides 200 is integrated to a single semiconductor substrate 110. A plurality of power supply electrodes 150 is formed onto an upper surface of each laser waveguide 200 corresponding to them. Each of a plurality of connection wirings Lc electrically connects an electrode pad Pe corresponding to each of the power supply electrodes 150 of the laser waveguide 200. An organic insulation film 170 is formed so as to contain a place where each connection wiring Lc which has to be insulated and each power supply electrode 150 are crossed. An inorganic insulation film 180 coats a first part as a front end surface S1 side of each laser waveguide 200 from the organic insulation film 170 and a second part as a rear end surface S2 side.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] Semiconductor lasers are used as light sources in electronic devices such as printers and head-mounted displays (HMDs). In order to cope with the higher resolution of such electronic devices that handle images, a multi-beam semiconductor laser device is adopted.

[0003] In order to miniaturize lenses and MEMS mirrors, it is required to narrow the beam pitch. When the beam pitch becomes narrower than the ball diameter of wire bonding or the solder pattern width of die bonding, it becomes impossible to secure an area for directly performing wire bonding or die bonding on the electrode on the upper surface of the laser waveguide. As a result, it is necessary to form the electrode pad closer to the end of the chip (semiconductor substrate). In this case, the connection wiring (laminated wiring) connecting the electrode pad and the laser waveguide crosses the laser waveguide (Patent Document 1).

[0004] Specifically, the connection wiring connecting the power supply electrode (P-side electrode) formed on the upper surface of the central laser waveguide and the electrode pad crosses the adjacent laser waveguide. Focusing on the intersection of the connection wiring and the laser waveguide, an insulating layer is inserted between the connection wiring and the power supply electrode of the laser waveguide, and a laminated wiring structure is formed. In this laminated wiring structure, an interlayer insulating film inserted between the connection wiring and the power supply electrode is made of an organic insulating material such as polyimide.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The inventor has studied a multi-beam semiconductor laser device with a narrow beam pitch and has come to recognize the following problems.

[0007] End faces of a plurality of laser waveguides of a multi-beam semiconductor laser device are subjected to AR (Anti Reflection) coating or HR (High Reflection) coating. FIG. 1 is a diagram for explaining a coating process. Prior to the coating process, semiconductor chips 4 (dies) are cut out from a wafer as a die array (LD bar) 6 in which a plurality of them are integrated. The LD bar 6 is sandwiched and supported / fixed by a spacer 2 which is a jig. In this state, the cleavage plane 8 of the LD bar 6 is coated. After the coating, a plurality of semiconductor chips 4 are cut out from the LD bar 6 by a pelletizing process.

[0008] When coating the cleavage plane 8, if an organic insulating material for forming an insulating layer of a laminated wiring structure floats and adheres to the cleavage plane 8, it will have an adverse effect on the optical characteristics of the coating and the long-term reliability of the laser device.

[0009] Note that this problem should not be regarded as a general recognition of those skilled in the art. Furthermore, this problem was uniquely recognized by the inventors.

[0010] One aspect of the present disclosure has been made in view of such problems.

Means for Solving the Problems

[0011] One aspect of the present disclosure relates to a multi-beam semiconductor laser device. The multi-beam semiconductor laser device includes: a plurality of three or more laser waveguides integrated adjacent to each other on a single semiconductor substrate; a plurality of power supply electrodes formed on the upper surfaces of the corresponding laser waveguides; a plurality of electrode pads corresponding to the plurality of laser waveguides; a plurality of connection wirings corresponding to the plurality of laser waveguides, each electrically connecting the power supply electrode of the corresponding laser waveguide and the corresponding electrode pad; an organic insulating film formed including a portion where the connection wirings to be insulated from each other and the power supply electrodes cross; an inorganic insulating film covering, among the organic insulating film, a first portion that is a front end face side portion of the multi-beam semiconductor laser device and a second portion that is a rear end face side portion of the multi-beam semiconductor laser device.

[0012] In addition, combinations of the above components arbitrarily, and those obtained by mutually substituting the components and expressions of the present disclosure among methods, devices, systems, etc. are also effective as aspects of the present disclosure.

Advantages of the Invention

[0013] According to one aspect of the present disclosure, a decrease in reliability in the coating process can be suppressed.

Brief Description of the Drawings

[0014]

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Modes for Carrying Out the Invention

[0015] (Overview of Embodiment) The overview of some exemplary embodiments of the present disclosure will be described. This overview is provided as a prelude to the detailed description that follows or for the purpose of a basic understanding of the embodiments. The overview simplifies and describes some concepts of one or more embodiments and does not limit the scope of the invention or the disclosure. Also, this overview is not an exhaustive overview of all possible embodiments and does not limit essential components of the embodiments. For convenience, "one embodiment" may be used to refer to one embodiment (example or modification) or a plurality of embodiments (examples or modifications) disclosed in this specification.

[0016] A multi-beam semiconductor laser device according to an embodiment includes: a plurality of three or more laser waveguides integrated adjacent to each other on a single semiconductor substrate; a plurality of power supply electrodes formed on the upper surfaces of the corresponding laser waveguides; a plurality of electrode pads corresponding to the plurality of laser waveguides; a plurality of connection wirings corresponding to the plurality of laser waveguides and each electrically connecting the power supply electrode of the corresponding laser waveguide and the corresponding electrode pad; an organic insulating film formed including a portion where the connection wiring to be insulated from each other and the power supply electrode intersect; an inorganic insulating film covering a first portion which is a portion on the front end face side of the multi-beam semiconductor laser device and a second portion which is a portion on the rear end face side of the multi-beam semiconductor laser device in the organic insulating film.

[0017] According to this configuration, when coating the front end face and the rear end face of the multi-beam semiconductor laser device, by covering the portion of the organic insulating film where the organic insulating material is likely to scatter with the inorganic insulating film, it is possible to suppress the mixing of the organic insulating material into the coating film, and to suppress the deterioration of the optical characteristics of the coating and the decrease in the reliability of the multi-beam semiconductor laser device.

[0018] In one embodiment, the inorganic insulating film may further cover a third portion which is the upper surface side of the multi-beam semiconductor laser device in the organic insulating film. Thereby, the exposed area of the organic insulating film can be further reduced, and the mixing of the organic insulating material into the coating film can be further suppressed.

[0019] In one embodiment, the inorganic insulating film may be formed between the organic insulating film and the connection wiring in the third portion. In this configuration, in the wiring formation process, the amount of the organic insulating film scattered to the semiconductor manufacturing apparatus can be reduced. Also, the adhesion between the metal wiring and the inorganic insulating film is higher than the adhesion between the metal wiring and the organic insulating film. In this configuration, since the connection wiring is formed on the inorganic insulating film instead of the organic insulating film, wiring peeling and the like are less likely to occur, and the reliability can be improved.

[0020] In one embodiment, the inorganic insulating film may be formed above the connection wiring in the third portion.

[0021] In one embodiment, the inorganic insulating film may include a first layer formed below the connection wiring and a second layer formed above the connection wiring in the third portion.

[0022] In one embodiment, the inorganic insulating film may cover the entire organic insulating film.

[0023] In one embodiment, the organic insulating film may be formed in a single rectangular region including a part of a plurality of power supply electrodes, and an opening may be provided at a connection portion between a corresponding connection wiring and the power supply electrode.

[0024] In one embodiment, the plurality of electrode pads may be arranged in a pad region adjacent to the laser region. The organic insulating film may be formed across the laser region and the pad region, and the plurality of power supply electrodes and the plurality of electrode pads may be formed on the organic insulating film. The laser region in this specification refers to a region in which a plurality of laser oscillation structures including laser waveguides formed corresponding to a plurality of emitters and corresponding power supply electrodes are integrated.

[0025] It is difficult to form the organic insulating film thinly, and since it has higher toughness than the inorganic insulating film, it hinders pelletization and cleavage. Therefore, in one embodiment, the organic insulating film may not be formed in the outer peripheral region near the four sides of the semiconductor substrate. Thereby, pelletization and cleavage can be facilitated.

[0026] In one embodiment, the organic insulating film may be formed at each location where the connection wiring and the power supply electrode that should be insulated from each other intersect. In this case, since the absolute amount of the organic insulating film decreases, the amount of scattering of the organic insulating material can be reduced.

[0027] In one embodiment, the multi-beam semiconductor laser element may emit light in the red to infrared region.

[0028] (Embodiment) Hereinafter, the present disclosure will be described with reference to the drawings based on preferred embodiments. The same or equivalent components, members, and processes shown in each drawing are denoted by the same reference numerals, and redundant descriptions will be omitted as appropriate. Further, the embodiments are illustrative rather than limiting the disclosure, and not all the features and combinations thereof described in the embodiments are necessarily essential to the disclosure.

[0029] The dimensions (thickness, length, width, etc.) of each member described in the drawings may be enlarged or reduced as appropriate for ease of understanding. Furthermore, the dimensions of a plurality of members do not necessarily represent their size relationships. On the drawing, even if a member A is drawn thicker than another member B, member A may be thinner than member B.

[0030] (Embodiment 1) FIG. 2 is a perspective view of a semiconductor laser element 100 according to Embodiment 1. The semiconductor laser element 100 is an end-face emitting type semiconductor laser element and is a multi-beam semiconductor laser having a plurality of m (m≥3) emitters. In this embodiment, the number of emitters is 4.

[0031] The semiconductor laser element 100 includes an N-type semiconductor substrate 110 and a stacked growth layer 102 formed on the N-type semiconductor substrate 110. The stacked growth layer 102 includes an N-type clad layer 120, a light emitting layer (active layer) 130, a P-type clad layer 140, and a P-type contact layer (not shown), and is sequentially stacked on the N-type semiconductor substrate 110. The light emitting layer 130 includes an N-type guide layer (lower guide layer), an active layer composed 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 stacked growth layer 102 may be selected according to the required oscillation wavelength and are not particularly limited in the present disclosure.

[0032] The semiconductor laser device 100 has a central laser region 902 and pad regions 904, 906. In the laser region 902, m (m ≧ 3) laser waveguides 200_1 to 200_m adjacent to each other in the first direction (x direction) are formed. Each laser waveguide 200 has a stripe structure extending in the second direction (z direction) orthogonal to the first direction (x direction), and emits a beam in the z direction.

[0033] In the stacked growth layer 102, a waveguide structure for confining light is formed, and the cleavage planes at both ends of this waveguide structure serve as mirrors, forming a Fabry - Perot type laser waveguide 200. In this example, four laser waveguides 200_1 to 200_4 are formed, and beams BM1 to BM4 are emitted in the z direction from the front end face (emission end face) S1. The front end face S1 and the rear end face S2 of each laser waveguide 200 are coated to give a desired reflectivity.

[0034] The waveguide structure can be, for example, an embedded ridge waveguide.

[0035] Alternatively, the waveguide structure may be a CSP (Channeled Substrate Planer) 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 120 in the groove portion is relatively thick.

[0036] The embedded ridge structure and the CSP structure are waveguide structures using refractive index distribution, but the present disclosure is not limited thereto, and a gain waveguide structure using gain distribution may also be used. These structures are light confinement structures and can also be regarded as current constriction structures.

[0037] On the upper surface of each laser waveguide 200, an insulating film 160 for contact is formed. In the insulating film 160 for contact, rectangular openings extending in the z direction are formed on the upper surfaces of the laser waveguides 200_1 to 200_n. Along these openings, power supply electrodes (P-side electrodes) 150 are formed. In order to drive the laser waveguides 200 independently, the power supply electrodes 150 are electrically insulated from each other. Also, the P-type semiconductor part has an electrical resistance between each emitter and can be driven electrically independently. In the present embodiment, the power supply electrode 150 is a strip-shaped electrode extending along the z direction on the upper surface of the laser waveguide 200.

[0038] On the back surface of the laser waveguide 200, an N-side electrode 152 is formed.

[0039] For power supply to the laser waveguides 200, corresponding to a plurality of laser waveguides 200_1 to 200_4, a plurality of chip-side electrode pads (hereinafter simply referred to as electrode pads) Pe1 to Pe4 and a plurality of connection wirings Lc1 to Lc4 are provided.

[0040] The plurality of electrode pads Pe1 to Pe4 are formed in pad regions 904 and 906 adjacent to the laser region 902 in the x direction. In the case of junction-up mounting, bonding wires are connected to the electrode pads Pe1 to Pe4, and in the case of junction-down mounting, solder is connected.

[0041] Each connection wiring Lci (i = 1, 2, 3, 4) electrically connects the power supply electrode 150 of the corresponding laser waveguide 200_i and the corresponding electrode pad Pi.

[0042] Among the plurality of laser waveguides 200_1 to 200_4, for the two inner ones (200_2, 200_3), the connection wirings Lc2 and Lc3 cross the power supply electrodes 150 of the outer laser waveguides 200. Specifically, the connection wiring Lc2 crosses the power supply electrode 150_1 of the laser waveguide 200_1. Similarly, the connection wiring Lc3 crosses the power supply electrode 150_4 of the laser waveguide 200_4.

[0043] The organic insulating film 170 is formed to include a location where the connection wiring Lc and the power supply electrode 150, which should be insulated from each other, intersect, ensuring electrical insulation between the connection wiring Lc2 and the power supply electrode 150_1 and between the connection wiring Lc3 and the power supply electrode 150_4.

[0044] In the present embodiment, the organic insulating film 170 covers a wide range including not only the formation ranges of the connection wirings Lc2 and Lc3 but also the formation ranges of the connection wirings Lc1 and Lc4. In this embodiment, the organic insulating film 170 is formed in a single rectangular region including a part of the plurality of power supply electrodes 150_1 to 150_4 included in the laser region 902.

[0045] Openings are provided in the organic insulating film 170 at the connection locations of the corresponding connection wiring Lci and the power supply electrode 150_i (i = 1 to 4). In this embodiment, openings 171 to 174 are formed in the organic insulating film 170. Through the opening 171, the connection wiring Lc1 and the power supply electrode 150_1 are electrically connected; through the opening 172, the connection wiring Lc2 and the power supply electrode 150_2 are electrically connected; through the opening 173, the connection wiring Lc3 and the power supply electrode 150_3 are electrically connected; and through the opening 174, the connection wiring Lc4 and the power supply electrode 150_4 are electrically connected.

[0046] As the material of the organic insulating film 170, organic materials such as polyimide can be used. Polyimide can fill the unevenness of the substrate and is likely to have a flat surface, so it has the advantages of being able to planarize the connection wiring Lc and improving the film coverage. Also, since it is tough and has high durability against external forces, it is less likely to cause damage such as cracks and can enhance the electrical insulation between electrodes.

[0047] The semiconductor laser device 100 further includes inorganic insulating films 180f and 180r. The inorganic insulating film 180f covers a first portion 176 (a plane substantially orthogonal to the Z direction, refer to the cross-sectional view along line B-B' in FIG. 4) of the organic insulating film 170, which is the portion on the front-end face S1 side of the laser waveguide 200. The inorganic insulating film 180r covers a second portion 177 (a plane substantially orthogonal to the Z direction) of the organic insulating film 170, which is the portion on the rear-end face S2 side of the laser waveguide 200.

[0048] FIG. 3 is a plan view of the semiconductor laser device 100 of FIG. 2. FIG. 4 is a cross-sectional view of the semiconductor laser device 100 of FIG. 3 along lines A-A' and B-B'.

[0049] The above is the configuration of the semiconductor laser device 100. The advantages of this semiconductor laser device 100 will be described. The advantages of the semiconductor laser device 100 will become clear by comparison with the comparative technology.

[0050] The comparative technology is obtained by omitting the inorganic insulating films 180f and 180r from the semiconductor laser device 100 according to the embodiment. In the comparative technology, in the coating process of FIG. 1, the first portion and the second portion of the organic insulating film 170 are exposed. Therefore, when coating the front-end face S1 and the rear-end face S2, the organic insulating material and the compositional substances of the organic material scattered to the periphery adhere to the end faces of the semiconductor portion or are mixed into the coating, and as a result, the optical characteristics of the coating are adversely affected, or the long-term reliability of the semiconductor laser device is adversely affected.

[0051] On the other hand, in the semiconductor laser device 100 according to the embodiment, since the first portion and the second portion of the organic insulating film 170 are not exposed, scattering of the organic insulating material and the compositional substances of the organic material can be suppressed in the coating process of FIG. 1, and adhesion to the end faces of the semiconductor portion and mixing into the coating can be prevented. Thereby, the optical characteristics of the coating can be stabilized, and the long-term reliability of the semiconductor laser device can be improved.

[0052] Next, a modification related to Embodiment 1 will be described.

[0053] (Modification 1.1) FIG. 5 is a perspective view of the semiconductor laser element 100a according to Modification 1.1. FIG. 6 is a plan view of the semiconductor laser element 100a in FIG. 5. FIG. 7 is a cross-sectional view of the semiconductor laser element 100a taken along line A-A' and line B-B' in FIG. 6.

[0054] In addition to the first and second portions that are the surfaces of the organic insulating film 170 that are substantially orthogonal to the z direction of the semiconductor laser element 100, the inorganic insulating film 180a covers the third portion (the surface that is substantially orthogonal to the y direction) of the organic insulating film 170 on the upper surface side of the semiconductor laser element 100. The third portion is the upper surface of the organic insulating film 170. Further, the inorganic insulating film 180a covers the portion that is the surface of the organic insulating film 170 that is substantially orthogonal to the x direction of the semiconductor laser element 100. That is, the inorganic insulating film 180a covers the entire organic insulating film 170. The inorganic insulating film 180a and the organic insulating film 170 have openings 171 to 174 formed at the same positions, and through the openings 171 to 174, the connection wirings Lc1 to Lc4 are electrically connected to the power supply electrodes 150_1 to 150_4.

[0055] The above is the configuration of the semiconductor laser element 100a according to Modification 1.1. According to this semiconductor laser element 100a, similar to the semiconductor laser element 100 according to Embodiment 1, in the coating process, the scattering of the organic insulating material can be suppressed, and the mixing into the coating can be prevented. As a result, the optical characteristics of the coating can be stabilized, and the long-term reliability of the semiconductor laser element can be improved.

[0056] Also, according to the semiconductor laser element 100a according to Modification 1.1, in the process after forming the organic insulating film 170, specifically, in the process of forming the connection wiring Lc or the electrode pad Pe, or in the coating process, the scattering of the organic insulating material into the manufacturing apparatus can be prevented, and the contamination of the manufacturing apparatus can be prevented.

[0057] Furthermore, in the semiconductor laser element 100a according to Modification 1.1, the following secondary effects can be obtained. For comparison, in Embodiment 1, since most of the connection wiring Lc is formed so as to be in contact with the organic insulating film 170, depending on the combination of materials, the adhesion of the connection wiring Lc may deteriorate. On the other hand, in the semiconductor laser element 100a according to Modification 1.1, since the connection wiring Lc is formed on the inorganic insulating film 180a, the adhesion can be enhanced, and the reliability of the semiconductor laser element 100a can be improved.

[0058] (Modification 1.2) FIG. 8 is a plan view of the semiconductor laser element 100b according to Modification 1.2. FIG. 9 is a cross-sectional view of the semiconductor laser element 100b taken along lines A-A' and B-B' of FIG. 8.

[0059] The inorganic insulating film 180b covers not only the surface of the organic insulating film 170 but also the upper surface of the contact insulating film 160 over the entire semiconductor laser element 100b. The inorganic insulating film 180b and the organic insulating film 170 have openings 171 to 174 formed at the same locations, and through the openings 171 to 174, the connection wirings Lc1 to Lc4 are electrically connected to the power supply electrodes 150_1 to 150_4.

[0060] According to the semiconductor laser element 100b according to Modification 1.2, the same effects as those of the semiconductor laser element 100a according to Modification 1.1 can be obtained.

[0061] (Modification 1.3) FIG. 10 is a plan view of the semiconductor laser element 100c according to Modification 1.3. FIG. 11 is a cross-sectional view of the semiconductor laser element 100c taken along lines A-A' and B-B' of FIG. 10.

[0062] Similar to Modification 1.1, the inorganic insulating film 180c covers the entire organic insulating film 170. In Modification 1.3, the inorganic insulating film 180c is not formed in the range where the electrode pad Pe and the connection wiring Lc are formed. This point is different from the inorganic insulating film 180b of Modification 1.1.

[0063] According to the semiconductor laser element 100c according to Modification 1.3, similarly to the semiconductor laser element 100 according to Embodiment 1, in the coating process, scattering of the organic insulating material can be suppressed, and mixing into the coating can be prevented. Thereby, the optical characteristics of the coating can be stabilized, and the long-term reliability of the semiconductor laser element can be improved.

[0064] (Modification 1.4) FIG. 12 is a plan view of the semiconductor laser element 100d according to Modification 1.4. FIG. 13 is a cross-sectional view of the semiconductor laser element 100d of FIG. 12 taken along line A-A' and line B-B'.

[0065] In the semiconductor laser elements 100, 100a to 100c described so far, the inorganic insulating film 180 was inserted between the organic insulating film 170 and the connection wiring Lc (and the electrode pad Pe). In contrast, in this modification, the inorganic insulating film 180d is formed above the connection wiring Lc and the electrode pad Pe. The inorganic insulating film 180d covers the front surface of the semiconductor laser element 100d, and openings 181 to 184 are formed in portions of the electrode pads Pe1 to Pe4. Through these openings 181 to 184, the electrical connection means can be electrically connected to the electrode pad Pe. The electrical connection means can be a ball of a bonding wire in the case of junction-up mounting and solder in the case of junction-down mounting.

[0066] (Modification 1.5) FIG. 14 is a plan view of the semiconductor laser element 100e according to Modification 1.5. FIG. 15 is a cross-sectional view of the semiconductor laser element 100e of FIG. 14 taken along line A-A' and line B-B'.

[0067] This modification example 1.5 is a combination of modification example 1.2 related to FIGS. 8 and 9 and modification example 1.4 related to FIGS. 12 and 13. The inorganic insulating film 180 is formed of two layers, a lower inorganic insulating film 180e1 and an upper inorganic insulating film 180e2. As shown in FIG. 15, the lower inorganic insulating film 180e1 is inserted between the contact insulating film 160 and the connection wiring Lc and has the same function as the inorganic insulating film 180b in FIGS. 8 and 9. The upper inorganic insulating film 180e2 is formed above the connection wiring Lc and has the same function as the inorganic insulating film 180d in FIGS. 12 and 13. Modification example 1.5 has the combined effects of modification example 1.2 and modification example 1.4.

[0068] (Embodiment 2) FIG. 16 is a plan view of the semiconductor laser element 100A according to Embodiment 2. FIG. 17 is a cross-sectional view taken along line A-A' and line B-B' of the semiconductor laser element 100A in FIG. 16.

[0069] In Embodiment 1 and Embodiment 2, the formation range of the organic insulating film 170A is different. Specifically, in Embodiment 2, the organic insulating film 170A is formed over a wide range over the entire semiconductor laser element 100A including not only the laser region 902 but also the pad region 904. However, since the organic insulating film 170A hinders cleavage, it is formed so as to avoid the outer peripheral portions of the four sides that become the cleavage surface and the pelletized surface of the semiconductor laser element 100A.

[0070] The inorganic insulating film 180A is formed over the entire semiconductor laser element 100A so as to cover the entire organic insulating film 170A. Openings 171 to 174 are formed at the same positions in the organic insulating film 170A and the inorganic insulating film 180A.

[0071] The above is the configuration of the semiconductor laser element 100A. According to this semiconductor laser element 100A, the same effects as those of the semiconductor laser element 100a according to modification example 1.1 can be obtained.

[0072] Note that also in Embodiment 2, as described in Embodiment 1, various variations are conceivable for the formation range of the inorganic insulating film 180A.

[0073] (Modification Example 2.1) As shown in FIGS. 2 to 4, the inorganic insulating film 180A may be formed so as to individually cover a first portion (a plane substantially orthogonal to the z direction), which is on the front end face S1 side of the laser waveguide 200, and a second portion (a plane substantially orthogonal to the z direction), which is on the rear end face S2 side of the laser waveguide 200, among the organic insulating films 170A.

[0074] (Modification Example 2.2) As shown in FIGS. 10 and 11, the inorganic insulating film 180A may not be formed in the range where the electrode pad Pe and the connection wiring Lc are formed.

[0075] (Embodiment 3) FIG. 18 is a perspective view of the semiconductor laser element 100B according to Embodiment 3. The organic insulating films 170B are independently provided at each location where the connection wiring Lc and the power supply electrode 150 intersect. Specifically, the organic insulating film 170B_1 is provided at the location where the connection wiring Lc2 intersects the power supply electrode 150_1, and the organic insulating film 170B_4 is provided at the location where the connection wiring Lc3 intersects the power supply electrode 150_4.

[0076] The inorganic insulating film 180B_1 is formed so as to cover the entire organic insulating film 170B_1, and the inorganic insulating film 180B_4 is formed so as to cover the entire organic insulating film 170B_4.

[0077] The above is the configuration of the semiconductor laser element 100B. According to this semiconductor laser element 100B, the same effects as those of the semiconductor laser element 100a according to Modification Example 1.1 can be obtained. Furthermore, since the organic insulating film 170B has a smaller volume than the organic insulating films 170 and 170A in Embodiments 1 and 2 and their modification examples, there is an advantage that the absolute amount of the organic insulating material that can originally scatter is small.

[0078] Note that also in Embodiment 3, as described in Embodiment 1, various variations are conceivable for the formation range of the inorganic insulating film 180B.

[0079] (Modification Example 3.1) As shown in FIGS. 2 to 4, the inorganic insulating film 180B may be formed so as to individually cover a first portion (a plane substantially orthogonal to the z direction) on the front end face S1 side of the laser waveguide 200 and a second portion (a plane substantially orthogonal to the z direction) on the rear end face S2 side of the laser waveguide 200 among the organic insulating films 170B.

[0080] (Modification Example 2.2) As shown in FIGS. 10 and 11, the inorganic insulating film 180B may not be formed in the range where the electrode pad Pe and the connection wiring Lc are formed.

[0081] The embodiments merely show the principles and applications of the present invention, and many modifications and arrangement changes are allowed within the scope that does not deviate from the idea of the present invention defined in the claims.

Explanation of Reference Numerals

[0082] 100 Semiconductor laser element S1 Front end face S2 Rear end face 902 Laser region 904, 906 Pad regions 110 N-type semiconductor substrate 120 N-type clad layer 130 Light-emitting layer 140 P-type clad layer 160 Contact insulating film Pe Electrode pad Lc Connection wiring 150 Power supply electrode 152 N-side electrode 160 Contact insulating film 170 Organic insulating film 180 Inorganic insulating film 200 Laser waveguide

Claims

1. A multi-beam semiconductor laser device, comprising: A plurality of three or more laser waveguides integrated adjacent to each other on a single semiconductor substrate; A plurality of power supply electrodes formed on the upper surfaces of the corresponding laser waveguides; A plurality of electrode pads corresponding to the plurality of laser waveguides; A plurality of connection wirings corresponding to the plurality of laser waveguides, each electrically connecting the power supply electrode of the corresponding laser waveguide and the corresponding electrode pad; An organic insulating film formed including a portion where the connection wiring and the power supply electrode to be insulated from each other cross; An inorganic insulating film covering a first portion, which is a portion on the front end face side of the multi-beam semiconductor laser device, and a second portion, which is a portion on the rear end face side of the multi-beam semiconductor laser device, of the organic insulating film; A multi-beam semiconductor laser device, characterized by comprising the above.

2. The multi-beam semiconductor laser device according to claim 1, wherein the inorganic insulating film further covers a third portion, which is the upper surface side of the multi-beam semiconductor laser device, of the organic insulating film.

3. The multi-beam semiconductor laser device according to claim 2, wherein the inorganic insulating film is formed between the organic insulating film and the connection wiring in the third portion.

4. The multi-beam semiconductor laser device according to claim 2, wherein the inorganic insulating film is formed above the connection wiring in the third portion.

5. The multi-beam semiconductor laser device according to claim 2, wherein the inorganic insulating film includes a first layer formed below the connection wiring and a second layer formed above the connection wiring in the third portion.

6. The multi-beam semiconductor laser device according to any one of claims 1 to 5, wherein the inorganic insulating film covers the entire organic insulating film.

7. The multi-beam semiconductor laser device according to any one of claims 1 to 5, wherein the organic insulating film is formed in a single rectangular region including a part of the plurality of power supply electrodes, and an opening is provided at a connection portion between the corresponding connection wiring and the power supply electrode.

8. The plurality of electrode pads are arranged in a pad region adjacent to the laser region, The multi-beam semiconductor laser device according to claim 7, wherein the organic insulating film is formed across the laser region and the pad region, and the plurality of power supply electrodes and the plurality of electrode pads are formed on the organic insulating film.

9. The multi-beam semiconductor laser device according to claim 8, wherein the organic insulating film is not formed in an outer peripheral region near the four sides of the semiconductor substrate.

10. The multi-beam semiconductor laser device according to any one of claims 1 to 5, wherein the organic insulating film is formed at each location where the connection wiring and the power supply electrode, which should be insulated from each other, intersect.

11. The multi-beam semiconductor laser device according to any one of claims 1 to 5, which emits light in the red to infrared region.

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