JP2009117540A - Surface emitting laser element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode structure for preventing the collapse of the mesa post of an oxidized layer-constricted VCSEL element. <P>SOLUTION: The VCSEL element 100 has a rectangular-shape current injection region 20a in an oxidized constricted layer 20. An electrode lead wire 30 which is formed on the upper part of the mesa post 50 and connected to a p-side electrode 26 to supply an oscillating current to the mesa post 50 is formed at an angle position corresponding to one of peaks of the rectangular-shape current injection region 20a. Stress to be applied from the p-side electrode lead wire 30 to the mesa post 50 is reduced to prevent the collapse of the mesa post 50 due to the stress of the oxidized constricted layer 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a surface emitting laser element, and more particularly, to an oxide layer confined surface emitting laser element having a long element lifetime and excellent reliability.

  A surface emitting laser element is a semiconductor laser element that emits light in a direction orthogonal to a substrate surface. Unlike conventional Fabry-Perot resonator type semiconductor laser elements, surface-emitting laser elements can be arranged in a two-dimensional array on the same substrate, and in recent years in the field of data communications. Particular attention has been paid.

  A surface emitting laser element (hereinafter referred to as a VCSEL (Vertical-cavity Surface-emitting laser) element) is formed by forming a pair of multilayer mirrors (DBR mirrors) on a semiconductor substrate such as GaAs or InP. A laser resonator including an active layer serving as a light emitting region is provided between the DBR mirrors. Each DBR mirror is formed by laminating a large number of pairs of semiconductor layers and dielectric layers composed of a high refractive index layer / low refractive index layer. In the VCSEL device, an oxide confinement type device structure having a current injection region and a current blocking region, in which an oxide confinement layer for confining current is formed in the DBR mirror or in the vicinity of the active layer, has been conventionally used. Are known. An oxide layer constriction type VCSEL element is described in Patent Documents 1 and 2, for example. In addition to the current confinement function, an oxide confinement layer having a light confinement function is also known.

With reference to FIG. 5, the configuration of a conventional oxide layer constriction type VCSEL element will be described. The VCSEL element 200 has an n-Al _0.2 Ga _0.8 As / n-Al _0.9 Ga layer on the n-GaAs substrate 60 having a thickness of each layer of λ / (4n) (λ is an oscillation wavelength and n is a refractive index). _The lower DBR mirror 62 consisting of 35 pairs of _0.1 As, the lower cladding layer 64, the quantum well active layer 66, the upper cladding layer 68, and the thickness of each layer is λ / (4n) (λ is the oscillation wavelength, n is It has a laminated structure including an upper DBR mirror 70 composed of 25 pairs of p-Al _0.2 Ga _0.8 As / p-Al _0.9 Ga _0.1 As of (refractive index). The n-Al _0.2 Ga _0.8 As layer and the p-Al _0.2 Ga _0.8 As layer constitute the high refractive index layers of the DBR mirrors 62 and 70, and the n-Al _0.9 Ga _0.1 As layer and the p-Al _0.9 Ga _0.1 As layer The low refractive index layers of the DBR mirrors 62 and 70 are configured.

The upper DBR mirror 70 is formed of, for example, an Al _0.97 Ga _0.03 As layer instead of the single p-Al _0.9 Ga _0.1 As layer on the side close to the active layer 66, and has a periphery other than the central current injection region 72a. An oxidized constricting layer 72 constituting the current blocking region 72b is formed by selectively oxidizing the Al. The oxidized confinement layer 72 constitutes a current confinement structure and an optical confinement confinement structure in the VCSEL element 200.

  In the laminated structure, the upper DBR mirror 70 is processed into a cylindrical mesa post 74 having a diameter of, for example, 30 μm, by photolithography and etching, up to a layer close to the active layer 66 below the oxidized constricting layer 72.

  When forming the oxide layer narrowing type VCSEL element 200, the laminated structure processed into the mesa post 74 is oxidized in a water vapor atmosphere at a temperature of about 400 ° C. to oxidize the region on the outer side of the mesa post of the AlGaAs layer. . By this selective oxidation, an oxidized constricting layer 72 is formed. The oxidized constricting layer 72 includes a current blocking region 72b having an outer peripheral width of 10 μm and a central current injection region 72a.

  The mesa post 74 is filled with, for example, a polyimide layer 76 in order to flatten the upper portion. At the upper end of the mesa post 74, a ring-shaped (annular) p-side electrode 78 that contacts the upper end of the mesa post 74 with a width of about 5 μm to 10 μm is provided on the outer peripheral side. Further, the n-side electrode 80 is formed on the back surface of the n-GaAs substrate 60 after the substrate back surface is appropriately polished and the substrate thickness is adjusted to, for example, 200 μm. Further, a p-side electrode pad 82 for connecting to an external terminal with a wire is formed on the polyimide layer 76 so as to be in contact with the p-side electrode 78.

In the above process, the structure in which the laminated structure around the mesa post is completely removed is shown. Instead of this structure, in the oxide layer constricted VCSEL element, the outer periphery radially outward from the mesa post 74 is formed when the mesa post 74 is formed. A structure in which an annular groove is formed in a portion and a semiconductor stack outside the annular groove is left is generally employed. In this structure, the annular groove is later filled with a polyimide layer, and the electrode pad is formed on the upper layer of the annular groove on the outer peripheral side.
JP 2003-110196 A JP 2007-142375 A

The oxidized constriction layer 72 is formed of an AlGaAs layer having a ternary composition to which a small amount of Ga is added, such as an Al _0.98 Ga _0.02 As layer as described above. When an AlGaAs layer having this composition is used, the shape of the current injection region 72a formed in the oxidized constricting layer is formed in a good circular shape. However, in the formation of a semiconductor layer having a ternary composition, there is a problem that it is difficult to accurately control the composition (particularly between crystal growth batches) particularly in the case of a ternary semiconductor layer containing a trace amount of elements. . If the composition control accuracy is low, variations occur in the oxidation rate when forming the oxide constriction layer, and the size of the current injection region varies. The size of the current injection region affects the current characteristics (current vs. voltage, current vs. optical output) of the VCSEL element, and the variation causes a decrease in the yield of the VCSEL element.

  An oxide constriction layer using a binary composition AlAs layer instead of the AlGaAs layer is also known. However, when an AlAs layer is used for the oxide constriction layer, the shape of the current injection region 72a does not become a circular shape that accurately reflects the outer peripheral shape of the mesa post 74 when the AlAs layer is oxidized and converted into an Al oxide layer. For example, there was a problem of becoming a substantially square. When the shape of the current injection region is not circular, for example, approximately square, non-uniform internal stress is generated on the mesa post, and the mesa post may collapse due to insufficient strength.

  In view of the above, the present invention improves the conventional oxide layer constriction type surface emitting laser element, and even when a material in which the current injection region is difficult to be circular is used for the oxide constriction layer, the mesa post has insufficient strength. It is an object of the present invention to provide a surface-emitting laser element that is difficult and has excellent durability.

  As a result of earnest research on the problem of insufficient strength of the mesa post of the VCSEL element, the present inventors have conceived that the insufficient intensity occurs due to the relationship with the lead line of the electrode of the VCSEL element. By employing the present invention, the present invention has been completed.

A surface-emitting laser device according to a first aspect of the present invention includes a substrate, a pair of DBR mirrors formed on the substrate, each including a lower DBR mirror and an upper DBR mirror, an active layer, and the vicinity of or above the active layer. Or a surface-emitting laser element comprising a stacked structure including an oxide constriction layer formed in the lower DBR mirror and having a current injection region in the center,
The laminated structure including at least the oxidized constricting layer forms a mesa post,
The current injection region has a substantially symmetrical structure with respect to each of two planes passing through the central axis of the mesa post and orthogonal to each other, and a first outer periphery in the vicinity where the two planes intersect with the outer periphery of the mesa post The portion protrudes outward in the mesa post radial direction from the second outer peripheral portion in the vicinity where the plane that equally divides the angle formed by the two planes and the outer periphery of the current injection region intersect,
The lead line of the electrode formed on the mesa post and supplying current to the current injection region is drawn from the mesa post to the radially outer side of the mesa post at the same angular position as the first outer peripheral portion when viewed from the center of the mesa post. It is characterized by that.

A surface-emitting laser device according to a second aspect of the present invention includes a substrate, a pair of DBR mirrors formed on the substrate and including a lower DBR mirror and an upper DBR mirror, an active layer, and the vicinity of or above the active layer. Or a surface-emitting laser element comprising a stacked structure including an oxide constriction layer formed in the lower DBR mirror and having a current injection region in the center,
The laminated structure including at least the oxidized constricting layer forms a mesa post,
The current injection region has a substantially symmetrical structure with respect to each of two planes passing through the mesa post central axis and orthogonal to each other, and a first outer peripheral portion in the vicinity where the two planes intersect with the outer periphery of the mesa post However, it protrudes outward in the mesa post radial direction from the second outer peripheral portion in the vicinity where the plane that equally divides the angle formed by the two planes and the outer periphery of the current injection region intersect,
A bent portion is formed on an outer side of the mesa post in the radial direction and in the vicinity of the mesa post on the lead line of the electrode that is formed on the mesa post and supplies current to the current injection region.

  In the VCSEL device according to the first aspect of the present invention, the stress caused by oxidation of the oxidized constricting layer is relatively low, and therefore the same angle as the first outer peripheral portion of the current injection region where the strength of the mesa post is high. In position, the stress from the electrode leader is applied to the mesa post. For this reason, the external force that causes the mesa post to collapse is not applied to the mesa post from the leader line, and the durability of the mesa post is improved.

  In the VCSEL device according to the second aspect of the present invention, since the bent portion is formed in the lead line on the outer side in the radial direction of the mesa post and in the vicinity of the mesa post, the stress applied to the mesa post from the lead line is relieved. Improves durability. In addition, it is preferable to form this bending part from mesa post from the center among the full length of a leader line.

  Prior to the description of the embodiment of the present invention, the shape generated in the current injection region will be described. FIGS. 6A and 6B are plan views of the wafer 44 used in manufacturing the VCSEL element and the manufacturing stage of the VCSEL element 200 formed in the wafer, respectively. GaAs, AlAs, and AlGaAs, which are compound semiconductors used when forming a VCSEL device, have a cubic zinc flash structure. In the wafer 44, as shown in FIG. 6A, the (100) plane of the compound semiconductor having the zinc flash structure is used as a wafer plane for growing a semiconductor layer, and the (01 * 1 *) plane is oriented as an orientation flat. Flat) direction. “1 *” is a symbol indicating “1” with a top bar. As shown in FIG. 5B, after the stack constituting the VCSEL element 200 is grown and processed into a cylindrical mesa post 74, the AlAs layer is oxidized from the outer periphery of the mesa post 74 to form a current injection region 72a. Then, the current injection region 72a does not have a circular shape reflecting the cylindrical shape of the mesa post 74, but has a substantially square shape as shown in FIG.

  The current injection region 72a has a substantially square shape because the AlAs layer has four outer peripheral surfaces whose crystal planes are represented by <100>, that is, (010), (01 * 0), (001) This is because the (001 *) plane has a faster oxidation rate than other portions, for example, the (01 * 1) plane. The ratio of this oxidation rate reaches about 1.23 times, for example. In such a substantially square current injection region 72a, due to the amount of oxidation, the mesa post has a minimum resistance to external stress at an angular position corresponding to the apex of the substantially square shape. Its resistance to external stress is maximized at the angular position corresponding to the midpoint of the side.

  The lead line of the electrode that supplies current to the VCSEL element also applies stress to the mesa post 74 according to its thickness. If the angle position of the maximum stress caused by the shape of the current injection region 72a is the same as the angle position where the lead line stress is applied, the stress applied to the mesa post is maximized, and the mesa post may collapse. . Therefore, in one embodiment of the present invention, the mesa post is prevented from collapsing by forming the electrode lead line at an angular position where the stress due to the shape of the current injection region is minimum. In another embodiment, a structure is adopted in which a bent portion is formed in the vicinity of the outer periphery of the mesa post on the electrode lead line to reduce the stress applied to the mesa post from the lead line.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing showing the embodiment, like elements are denoted by like reference numerals. FIG. 1 shows a planar structure of a VCSEL device according to the first embodiment of the present invention. The VCSEL element 100 of the present embodiment is different from the conventional VCSEL element 200 in particular in the direction in which the p-side electrode lead line 30 is drawn.

  The VCSEL device 100 according to the present embodiment has a cylindrical mesa post 50 at the central portion of the device, similarly to the conventional VCSEL device 200. The oxidized constricting layer formed inside the mesa post 50 has a substantially square current injection region 20a at the center and an annular current blocking region 20b surrounding the current injection region 20a. An annular p-side electrode 26 is formed on the top of the mesa post 50, and the p-side electrode 26 is connected to the p-side electrode pad 36 formed in the peripheral region 52 on the outer peripheral side of the mesa post 50 via the p-side electrode lead wire 30. Connected to. An n-side electrode that is formed below the mesa post 50 and supplies a current to the mesa post 50 is connected to an n-side electrode pad 38 formed in the peripheral region 52 via an n-side electrode lead line 34.

  FIG. 2 is a cross-sectional view showing the structure of the VCSEL element 100 of the above embodiment. The VCSEL device 100 has an undoped GaAs substrate 10 and a laminated structure deposited thereon. The stacked structure includes a lower DBR mirror 12 made of an undoped semiconductor, an undoped semiconductor buffer layer 14, an n-contact layer 16, an n-clad layer, and a laser active layer 18 having a multiple quantum well structure, which are sequentially deposited from the substrate 10 side. It comprises an oxide constriction layer 20 including a current injection region 20a and a current blocking region 20b, a p-cladding layer 22, a p + -contact layer 24, an annular p-side electrode 26, and an upper DBR mirror 28 made of a dielectric layer. . In the laminated structure, a part from the laser active layer 18 to the annular p-side electrode 26 is formed on the mesa post 50, and the dielectric DBR mirror 28 is formed on the upper part of the mesa post 50 and a part of the peripheral region 52 surrounding the mesa post 50. A dielectric layer 40 is formed.

  The n-contact layer 16 extends radially outward from the lower portion of the mesa post 50, and an annular n-side electrode 32 is formed on the exposed surface thereof. The outer peripheral side of the n-contact layer 16 is surrounded by a dielectric layer 40 constituting the dielectric DBR mirror 28. An n-side electrode lead wire 34 made of Au is formed on the surface of the n-side electrode 32. The n-side electrode lead line 34 is formed at a position where the dielectric layer 40 is removed, extends from the surface of the n-side electrode 32, and terminates in an n-side electrode pad (38: FIG. 1). The annular p-side electrode 26 is formed on the outer peripheral side top of the mesa post 50, and the p-side electrode lead wire 30 is formed on the surface thereof. The lead wire 30 extends from the mesa post 50 and is formed in the peripheral region 52. The p-side electrode pad (36: FIG. 1) is terminated.

  Returning to FIG. 1, the p-side electrode lead wire 30 extends in the radial direction from the angular position near the apex of the square of the substantially square current injection region 20 a toward the outer peripheral side of the mesa post 50. In the vicinity of the apex of the current injection region 20a, the stress toward the outer peripheral side of the mesa post 50 by the current confinement layer 20 is the smallest. Therefore, the stress due to the p-side electrode lead wire 30 acts on the position where the stress applied from the current confinement layer 20 to the mesa post 50 is the smallest, and the possibility that the mesa post 50 collapses due to the stress due to the p-side electrode lead wire 30 is excluded. .

The manufacturing process of the VCSEL element 100 will be further described with reference to FIG. First, on the undoped GaAs substrate 10, a lower DBR mirror 12, an undoped semiconductor buffer layer 14, an n-contact layer 16, a laser active layer 18 including an n-clad multiple quantum well layer, an oxidized constricting layer 20, and the like are formed by epitaxial growth. A p-AlAs layer, a p-cladding layer 22 and a p + -contact layer 24 are sequentially formed to form a laminated structure. The lower DBR mirror 12 is composed of, for example, 34 pairs of GaAs layer / Al _0.9 Ga _0.1 As layer, and the laser active layer 18 has a GaInNAs well layer having 3 layers and a GaAs barrier layer having 4 layers.

  An annular p-side electrode 26 is formed on the surface of the laminated structure by vapor deposition. A Ti / Pt metal laminate is used for the p-side electrode 26. For example, the outer diameter of the p-side electrode is 30 μm and the inner diameter is 14 μm. Next, a laminated structure is formed on the mesa post 50 by wet etching with the inside of the p-side electrode 26 covered with a mask and using the p-side electrode 26 as a metal mask. The etching was performed halfway through the n-contact layer 16.

The AlAs layer in the obtained mesa post is oxidized from the outer peripheral side of the mesa post 50 in a water vapor atmosphere, and the outer peripheral portion of the AlAs layer is formed as an Al oxide layer to be formed in the current blocking region 20b. At this time, the current injection region 20a is formed by leaving a non-oxidized region having a diameter of about 6 to 7 μm on the inner peripheral side of the AlAs layer. Next, the outer wall of the mesa post 50 is covered with a dielectric film, and a semi-annular n-side electrode 32 is formed on the outer surface of the n-contact layer 16. For example, the outer diameter of the n-side electrode is 82 μm and the inner diameter is 42 μm. For the n-side electrode 32, for example, a metal laminate of AuGeNi / Au is used. Next, after forming the extraction electrodes 30, 34, 36, and 38, the dielectric DBR mirror 28 is formed on the entire surface. As the dielectric DBR mirror 28, for example, α-Si / SiO ₂ , SiNx / SiO ₂ , α-Si / Al ₂ O ₃ or the like is used. The number of pairs is determined by the combination of materials. For example, when α-Si / SiO ₂ is used, the number is 5 to 6 pairs. Next, the dielectric layers formed on the surfaces of the p-side electrode 26 and the n-side electrode 32 are removed by etching.

  Next, electrode lead lines 30 and 34 respectively connected to the p-side electrode 26 and the n-side electrode 32 are formed together with the electrode pads 36 and 38 by vapor deposition. The dielectric layer 40 on the surfaces of the electrode pads 36 and 38 is etched away to expose the surfaces of the electrode pads 36 and 38. Finally, the undoped GaAs substrate 10 is polished on the back side opposite to the surface on which the above-described laminated structure is formed, and the substrate thickness is adjusted to, for example, 150 μm to obtain a VCSEL device product. For example, the outer diameter of the product is 250 μm, and the outer diameter of the mesa post is about 30 μm.

  FIG. 3 is a plan view of a VCSEL device according to the second embodiment of the present invention. The VCSEL element 100A of the present embodiment example is different from the VCSEL element 100 of the first embodiment example in the lead-out direction of the p-side electrode lead line 30 and the shape of the p-side electrode lead line 30. Specifically, in the VCSEL device 100A of the present embodiment, the p-side electrode lead wire 30 is drawn from the mesa post 50 at an angular position corresponding to the center of one side of the square current injection region 20a. Further, the p-side electrode lead wire 30 has an S-shaped bent portion 30 a formed outside the mesa post 50 and in the vicinity of the mesa post. Other configurations are the same as those of the first embodiment. The S-shaped bent portion 30a reduces the stress applied to the mesa post 50 from the electrode lead wire 30 and prevents the mesa post 50 from collapsing. In this embodiment, the electrode lead wire 30 is drawn from the mesa post 50 at an angular position corresponding to the center of one side of the square current injection region 20a. However, the angle position of the electrode lead wire 30 with respect to the mesa post is , In any direction. The bent portion 30a is preferably arranged at a position closer to the mesa post than the center of the leader line.

  FIG. 4 is a plan view of a VCSEL element according to the third embodiment of the present invention. The VCSEL element 100B according to the present embodiment is an example in which four separation grooves 54 arranged in a ring shape are formed outside the current injection region 20a in the radial direction. Each separation groove 54 is formed in an angle range of approximately ¼ when viewed from the center of the mesa post 50. The four bridges 56 that separate the separation grooves 54 from each other coincide with the four vertexes of the substantially square-shaped current injection region 20a, and one of the four vertexes is the p-side electrode 26. It coincides with the angular position where the electrode lead line 30 extends. By forming the isolation groove 54, the stress generated in the current blocking region 20b of the oxidized constricting layer 20 is relaxed. With this configuration, the bridge 56 is formed at an angular position where the stress due to the oxidized constricting layer 20 is the smallest. Similarly, the p-side electrode lead line 30 is arranged at an angular position where the stress due to the oxidized constricting layer 20 is the smallest. This reduces the stress applied to the mesa post 50 and eliminates the possibility of the mesa post collapsing.

  Although the present invention has been described based on the preferred embodiment thereof, the surface emitting laser element of the present invention is not limited to the configuration of the above embodiment example, but from the configuration of the above embodiment example. Various modifications and changes are also included in the scope of the present invention.

  For example, in the above-described embodiment, an example is shown in which the current injection region is formed in a square shape, but the current injection region may not necessarily be a square shape. In the present invention, for example, the current injection region has a substantially symmetric structure with respect to each of two planes that pass through the central axis of the mesa post and are orthogonal to each other, and a plane that equally divides the angle formed by the two orthogonal planes. For a structure in which a first outer peripheral portion in the vicinity where the outer periphery of the current injection region intersects protrudes more in the mesa post radial direction than a second outer peripheral portion in the vicinity where the two planes and the mesa post outer periphery intersect It is applicable.

  The surface emitting laser element of the present invention can be used as a light source for optical communication using an optical fiber in the field of data communication.

1 is a plan view of a VCSEL element according to a first embodiment example of the present invention. FIG. FIG. 2 is a cross-sectional view of the VCSEL element in FIG. 1. The top view of the VCSEL element which concerns on the 2nd Example of this invention. The top view of the VCSEL element which concerns on the 3rd Example of this invention. Sectional drawing of the conventional VCSEL element. 2A and 2B are views for explaining problems related to formation of an oxidized constriction layer of a VCSEL element, and FIGS. 3A and 3B are a plan view of a wafer and a schematic plan view of a VCSEL element, respectively.

Explanation of symbols

100, 100A, 100B: VCSEL element 10: GaAs substrate 12: Lower DBR mirror 14: Buffer layer 16: n-contact layer 18: Laser active layer 20: Oxide constriction layer 20a: Current injection region 20b: Current blocking region 22: p -Clad layer 24: p + -contact layer 26: p-side electrode 28: dielectric DBR mirror 30: p-side electrode lead wire 30a: bent portion 32: n-side electrode 34: n-side electrode lead wire 36: p-side electrode pad 38 : N-side electrode pad 40: dielectric layer 44: wafer 50: mesa post 52: surrounding region 54: separation groove 56: bridge 200: VCSEL element 60: n-GaAs substrate 62: lower DBR mirror 64: lower cladding layer
66: quantum well active layer 68: upper cladding layer 70: upper DBR mirror 72: oxidation constriction layer 72a: current injection region 72b: current blocking region 74: mesa post 76: polyimide layer 78: p-side electrode 80: n-side electrode 82: p-side electrode pad

Claims (6)

A pair of DBR mirrors comprising a substrate and a lower DBR mirror and an upper DBR mirror formed on the substrate, an active layer, and an active layer, formed near or in the upper or lower DBR mirror, and current injection at the center In a surface emitting laser device comprising a laminated structure including an oxidized constricting layer having a region,
The laminated structure including at least the oxidized constricting layer forms a mesa post,
The current injection region has a substantially symmetrical structure with respect to each of two planes passing through the central axis of the mesa post and orthogonal to each other, and a first outer periphery in the vicinity where the two planes intersect with the outer periphery of the mesa post The portion protrudes outward in the mesa post radial direction from the second outer peripheral portion in the vicinity where the plane that equally divides the angle formed by the two planes and the outer periphery of the current injection region intersect,
The lead line of the electrode formed on the mesa post and supplying current to the current injection region is drawn from the mesa post to the radially outer side of the mesa post at the same angular position as the first outer peripheral portion when viewed from the center of the mesa post. A surface-emitting laser element characterized by the above.   The surface emitting laser element according to claim 1, wherein a bent portion is formed on the lead line in the radial direction outside of the mesa post and in the vicinity of the mesa post. A pair of DBR mirrors comprising a substrate and a lower DBR mirror and an upper DBR mirror formed on the substrate, an active layer, and an active layer, formed near or in the upper or lower DBR mirror, and current injection at the center In a surface emitting laser device comprising a laminated structure including an oxidized constricting layer having a region,
The laminated structure including at least the oxidized constricting layer forms a mesa post,
The current injection region has a substantially symmetrical structure with respect to each of two planes passing through the mesa post central axis and orthogonal to each other, and a first outer peripheral portion in the vicinity where the two planes intersect with the outer periphery of the mesa post However, it protrudes outward in the mesa post radial direction from the second outer peripheral portion in the vicinity where the plane that equally divides the angle formed by the two planes and the outer periphery of the current injection region intersect,
A surface-emitting laser characterized in that a bent portion is formed on the lead line of an electrode that is formed on the mesa post and that supplies current to the current injection region, on the radially outer side of the mesa post and in the vicinity of the mesa post. element.   The mesa post has a plurality of annularly arranged separation grooves on the outer side in the radial direction of the current injection region, and a bridge separating the separation grooves is formed at the same angular position as the leader line. The surface emitting laser element according to any one of 1 to 3.   The surface emitting laser element according to claim 1, wherein the upper DBR mirror is a dielectric DBR mirror.   The surface emitting laser element according to claim 5, wherein a dielectric layer constituting the dielectric mirror is formed in an outer peripheral region surrounding the mesa post, and the lead line is formed on the dielectric layer.

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