JP2004281969A - Surface-emitting semiconductor laser element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a highly reliable surface-emitting semiconductor laser element by compensating the strain produced in a semiconductor layer on the side opposite to the substrate of an active layer in the laser element. <P>SOLUTION: This surface-emitting semiconductor laser element is provided with an n-type Al<SB>0.9</SB>Ga<SB>0.1</SB>As/Al<SB>0.3</SB>Ga<SB>0.7</SB>As lower multilayered semiconductor reflection film 13, a quantum well active layer 15 composed of an undoped Al<SB>0.12</SB>Ga<SB>0.88</SB>As quantum well layer and an undoped Al<SB>0.3</SB>Ga<SB>0.7</SB>As barrier layer, and a current constricting layer formed by oxidizing the area 19a of a p-type AlAs layer 19 other than a current injecting area, and a p-type Al<SB>0.9</SB>Ga<SB>0.1</SB>As/Al<SB>0.3</SB>Ga<SB>0.7</SB>As upper multilayered semiconductor reflection film 21 successively laminated upon an n-type GaAs substrate 11 in this order. In this laser element, an undoped InGaAsP tensile-strain spacer layer 17 is provided between the active layer 15 and the current constricting layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surface emitting semiconductor laser element.
[0002]
[Prior art]
Generally, as a light source for an optical link for short-distance high-speed communication, an AlGaAs surface emitting semiconductor laser (Vertical Cavity Surface Emitting Laser (VCSEL)) having an oscillation wavelength of 850 nm manufactured on a GaAs substrate is used. The reason why the semiconductor laser element of this wavelength band is used is mainly because it is an AlGaAs-based material and can be easily manufactured, and the propagation loss of the currently used silica fiber is low.
[0003]
On the other hand, in short-distance communications such as homes, in-devices, between devices, and automobiles, it has become possible to use POF (Plastic Optical Fiber) that has a large core diameter and is inexpensive and easy to handle. Since the POF has a large core diameter of 100 to 1000 μm, alignment is easy and the cost of the transmission / reception module and fiber connector can be reduced. The ease of tip processing and construction is also a feature of POF.
[0004]
PMMA is generally used as a POF material. The low-loss wavelength region of PMMA-POF is limited, and is limited to three wavelengths of 650, 780, and 850 nm as wavelengths for realizing a semiconductor laser capable of high-speed communication. In particular, at 780 nm and 850 nm, from the resonator formation to the operation test can be performed at the wafer level, and a VCSEL that can be easily coupled to an optical fiber can be used as a light source. As a VCSEL, it is said that an element of 850 nm is easier to manufacture, and reliability at 780 nm tends to be lower than that of an element of 850 nm. However, the device in the 780 nm band has a lower loss of PMMA-POF than the device in the 850 nm band, and transmission over a longer distance is possible.
[0005]
Therefore, a ridge structure VCSEL having a short wavelength region in which Al is not included in the active region has been proposed in order to improve such reliability degradation in the 780 nm band (see, for example, Patent Document 1). In the above document 1, when AlGaAs containing Al is used in the active region in order to realize a shorter wavelength, the increase in non-radiative recombination centers due to the incorporation of oxygen into AlGaAs in the crystal growth or device manufacturing process, In order to reduce the laser oscillation efficiency, a GaAs quantum well and a GaInP barrier layer not containing Al are introduced in the active region. Here, GaAsP causes tensile strain because it does not lattice-match the GaAs substrate, but the total strain is reduced by using GaInP as compression strain.
[0006]
On the other hand, edge-emitting stripe lasers having Fabry-Perot resonators are widely used as light sources for CDs and CD-Rs using AlGaAs in the active region. Recently, recording speeds for CD-Rs and the like are being used. In order to improve this, an element having a high output exceeding 150 mW is also used. It is known that the reliability of the edge-emitting type stripe laser is advantageous for an element that does not contain Al in the active layer (for example, see Non-Patent Document 1). The reliability of the edge-emitting laser depends on the stability of the cleaved end face, and the end face is likely to be oxidized, which is considered to be the biggest cause. Therefore, a NAM (Non-Absorbing Mirror) structure in which light absorption at the end face is suppressed is generally used in high-power lasers in short wavelength AlGaInP semiconductor lasers. However, due to recent improvements in crystal growth equipment and purity of raw materials, the quality of AlGaAs crystals is extremely high, and crystal quality is unlikely to be the primary cause of deterioration. Further, since the VCSEL does not have a cleaved end face, there is no deterioration due to the end face. However, since the active region is removed by etching in the ridge-type VCSEL as described in Patent Document 1, there is a possibility that this surface may be affected by oxidation. On the other hand, recently, ion implantation type and selective oxidation type VCSELs that do not remove the active region by etching have become common. In the former, protons or the like are ion-implanted up to the upper part of the active region to insulate the current and confine the current in the central oscillation region. The latter performs current confinement by insulating the laminated AlAs or high Al composition AlGaAs by selective oxidation from the surroundings. At this time, the periphery needs to be removed by etching. However, since there is a deep selective oxidation portion where the current is confined from the portion where the active layer is exposed by etching, there is almost no influence of non-radiative recombination in the active layer exposed portion. It is also possible to adopt a process or structure in which etching for selective oxidation is stopped at the upper part of the active layer and the active layer is not exposed.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-1017153 [0008]
[Non-Patent Document 1]
D. Botez, Proceeding of SPIE, 1999, Vol. 3628, p. 7
[0009]
[Problems to be solved by the invention]
However, even in such a VCSEL structure, when AlGaAs is used for the active layer, the 780 nm device having the AlGaAs active layer containing a large amount of Al has a problem that the device deterioration is faster at 780 nm and 850 nm.
[0010]
In addition, in an element having a selective oxidation type current confinement structure that is becoming mainstream, AlAs and AlGaAs having a high Al composition are selectively oxidized from the exposed portion by side etching to oxidize regions other than the current injection region. Although the constriction layer is formed, the oxidized layer contains Al ₂ O _{3 and the} like, and the crystal state is different from that of the peripheral crystal, so that the peripheral crystal is distorted. Even when the current confinement layer is formed by ion implantation in a region other than the current injection region of the semiconductor layer, the crystallinity is deteriorated and distorted depending on the process conditions such as the implantation amount and the ion acceleration voltage.
[0011]
In view of the above circumstances, an object of the present invention is to provide a highly reliable surface emitting semiconductor laser element.
[0012]
[Means for Solving the Problems]
The surface emitting semiconductor laser device according to the present invention includes an optical resonator mirror comprising a lower semiconductor multilayer film on a GaAs substrate, an active layer, a selective oxidation type or ion implantation type current confinement layer, and an optical resonance comprising an upper semiconductor multilayer reflection film. In a surface-emitting type semiconductor laser device comprising a semiconductor layer formed by stacking mirrors in this order and a pair of electrodes for injecting current into the active layer, and emitting light from an end face parallel to the stacked surface of the semiconductor layer, A strain compensation layer for compensating for the strain of the current confinement layer is provided between the active layer and the upper semiconductor multilayer reflective film.
[0013]
The strain compensation layer may be provided between the active layer and the current confinement layer, or may be provided between the current confinement layer and the upper semiconductor multilayer reflective film, or the current confinement layer. It may be provided above and below. It is preferable to provide it between the active layer and the current confinement layer because the strain is compensated in a region near the active layer.
[0014]
Alternatively, in the case of a selective oxidation type current confinement layer, the current confinement layer is composed of a plurality of selectively oxidized layers, and the strain compensation layer is provided in a region sandwiched between the plurality of selectively oxidized layers. It may be. That is, after selective oxidation, the total strain of a plurality of selectively oxidized layers is compensated by a strain compensation layer provided between the selectively oxidized layers. In this case, since the thickness of the entire current confinement layer can be made thinner than in the case where the current confinement layer is composed of a single-layer selectively oxidized layer, distortion compensation can be effectively performed.
[0015]
The strain compensation layer is preferably made of at least one of InGaP, InGaAsP, AlGaInAsP, AlGaInP, GaAsP, and AlGaAsP.
[0016]
The oscillation wavelength band of the laser beam is preferably in the range from 730 nm to 820 nm. Furthermore, it is desirable that the range is from 770 nm to 800 nm.
[0017]
The “compensating for the distortion of the current confinement layer” means that the distortion of the current confinement layer has a distortion opposite to that of the current confinement layer and cancels out the distortion of the current confinement layer.
[0018]
【The invention's effect】
According to the surface-emitting type semiconductor laser device of the present invention, a strain compensation layer for compensating for the strain of the current confinement layer is provided between the active layer and the upper semiconductor multilayer reflective film, so that the distortion due to the crystallinity change of the current confinement layer is provided. Therefore, the strain can be prevented from affecting the active layer, and high reliability can be obtained.
[0019]
By using at least one of InGaP, InGaAsP, GaAsP, AlGaInAsP, AlGaInP, and AlGaAsP as the strain compensation layer, the strain of the current confinement layer can be compensated satisfactorily. In the above composition, except for GaAsP and AlGaAsP having tensile strain, it can be either compression strain or tensile strain by adjusting the composition ratio of elements. Further, if the composition does not contain Al, such as InGaP, InGaAsP, and GaAsP, it does not contain an Al element having a large band gap, so that it has a good band gap in order to efficiently inject carriers into the active layer. Laser characteristics can be obtained.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0021]
A surface-emitting type semiconductor laser according to a first embodiment of the present invention will be described together with a manufacturing method. A cross-sectional view of the semiconductor laser is shown in FIG.
[0022]
As shown in FIG. 1, the surface emitting semiconductor laser according to the present embodiment has an n-type GaAs buffer layer 12 (thickness: 200 nm, Si = 1 × 10 ¹⁸ cm ⁻³ ), n, Type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 13 (39.5 periods with a high reflection film and a low reflection film having a thickness corresponding to a quarter wavelength as one period) Stacked layer, Si = 1 × 10 ¹⁸ cm ⁻³ ), undoped Al _0.6 Ga _0.4 As spacer layer 14, undoped Al _0.12 Ga _0.88 As quantum well layer (3 layers of 10 nm, oscillation wavelength quantum well active layer 15 consisting of 780 nm) and undoped _Al 0.3 _{Ga 0.7} as barrier layer (having a thickness of 5nm layer two layers) and an undoped _Al 0.6 _{Ga 0.4} as spacer layer 16, an undoped InGa sP tensile strained spacer layer 17, p-type _Al 0.6 _{Ga 0.4} As spacer layer ^{18 (C = 8 × 10 17} cm -3), p -type AlAs layer 19 (quarter wavelength equivalent thickness, C = 2 × 10 ¹⁸ cm ⁻³ ), p-type Al _0.6 Ga _0.4 As spacer layer 20, p-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As upper semiconductor multilayer reflective film 21 (A high-reflection film having a thickness corresponding to a quarter wavelength and a low-reflection film with 29 periods stacked as one period, C = 2 × 10 ¹⁸ cm ⁻³ ), and a p-type GaAs contact layer 22 (thickness 10 nm, C = 5 × 10 ¹⁹ cm ⁻³ ) are sequentially stacked by MOCVD.
[0023]
Next, the p-type GaAs contact layer 22 is removed by etching the upper part of the light emitting region. In order to form the oscillation region, a cylindrical region having a diameter of 55 μm (r ₂ ) is left, and the periphery thereof is removed to a part of the lower semiconductor multilayer reflective film 13. By performing heat treatment (390 ° C., 10 minutes) in a furnace into which heated steam is introduced, the region 19a other than the current injection region of the p-type AlAs layer 19 is selectively oxidized to form a current confinement layer, and the diameter is 15 μm (r ₁ ) A non-oxidized region, that is, a current injection region is formed. A protective film 23 made of SiO ₂ is formed on the region left in the cylindrical shape by etching, the protective film 23 in the current injection region is removed, and a p-side electrode 24 is formed by laminating Ti / Pt / Au in this order. . Next, an n-side electrode 25 formed by laminating AuGe / Ni / Au in this order on the back surface of the n-type GaAs substrate 11 is formed.
[0024]
The surface-emitting type semiconductor laser device of the present embodiment manufactured as described above has an n-type GaAs buffer layer 12 and an n-type Al _0.9 Ga _0.1 As / Al _0.3 Ga ₀ on a GaAs substrate. _.7 As lower semiconductor multilayer reflective film 13, undoped Al _0.6 Ga _0.4 As spacer layer 14, undoped Al _0.12 Ga _0.88 As quantum well layer and undoped Al _0.3 Ga _0.7 As barrier layer Quantum well active layer 15, undoped Al _0.6 Ga _0.4 As spacer layer 16, undoped InGaAsP tensile strain spacer layer 17, p-type Al _0.6 Ga _0.4 As spacer layer 18, p-type AlAs layer 19 current confinement layer formed by oxidizing the regions 19a other than the current injection region, p-type _Al 0.6 _{Ga 0.4} As spacer layer 20, p-type _Al 0.9 Ga ₀ And ₁ As _/ Al 0.3 _{Ga 0.7} As upper semiconductor multilayer reflection film 21 and the p-type GaAs contact layer 22 semiconductor layer are laminated in this order, a pair of electrodes (n-side electrode 25 and the p-side electrode 24) And emits laser light from the surface of the p-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As upper semiconductor multilayer reflective film 21. n-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 13 and p-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As upper part Each of the semiconductor multilayer reflective films 21 is an optical resonator mirror, and the two mirrors constitute an optical resonator.
[0025]
In the present embodiment, the undoped InGaAsP tensile strain spacer layer 17 can compensate the compressive strain of the current confinement layer formed by selective oxidation of the p-type AlAs layer 19, so that the strain is transmitted to the active layer. Can be prevented.
[0026]
The active layer is made of AlGaAs, but may be made of InGaAsP lattice-matched with GaAs.
[0027]
In addition, an n-side electrode is formed on the back surface of the GaAs substrate, but when etching is performed to form a cylindrical region, a part of the n-type layer is etched, and the n-side electrode is exposed on the n-type layer exposed by the etching. An electrode may be formed. For example, in the present embodiment, an n-side electrode may be formed on the exposed n-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 13.
[0028]
By adjusting the optical thickness of the layer sandwiched between the lower semiconductor multilayer reflective film and the upper semiconductor multilayer reflective film, the spacer layer is set so that the antinode portion of the standing wave overlaps the active layer, The threshold can be lowered.
[0029]
By disposing the AlAs layer 19 between the p-type Al _0.5 Ga _0.5 As spacer layer 18 and the p-type Al _0.5 Ga _0.5 As spacer layer 20, and oxidizing the AlAs layer 19, Since the selective oxidation characteristic at the interface between the AlAs layer and the AlGaAs layer is good, highly accurate current confinement can be performed.
[0030]
In addition, the crystal growth by the MOCVD method has been described, but the MBE method using a solid or gas source can also be used.
[0031]
Although the number of quantum well layers is three, one single quantum well or two or more multiple quantum wells may be used. Furthermore, the number of quantum wells may be n, and the number of barrier layers may be n + 1.
[0032]
In addition to SiO ₂ , Al ₂ O ₃ , Si _x N _y , or the like can be used as the protective film.
[0033]
Also, the p-side electrode is formed by stacking Cr / Au in this order, the Au-Zn / Au is stacked in this order, the n-side electrode is stacked by AuGe / Au in this order, etc. It can also be used.
[0034]
Further, as the current confinement structure, a selective oxidation type in which a region other than the current injection region of the p-type AlAs layer 19 is oxidized is shown. However, the current confinement structure has a current confinement structure by injecting proton ions or the like into a region other than the current injection region. Similarly, by applying the present invention to the element, it is possible to compensate for the strain from the current confinement layer to the active layer.
[0035]
Although the current confinement layer formed by selective oxidation is one layer, a plurality of AlAs layers are provided, and an undoped InGaAsP tensile strain spacer layer is provided between the AlAs layers. The total strain of the current confinement layer that is selectively oxidized may be compensated by the undoped InGaAsP tensile strain spacer layer.
[0036]
In the present embodiment, the light emitting region has a shape protruding in a cylindrical shape, but as shown in FIG. 2, for example, a donut groove having an inner diameter (r ₂ ) of 55 μm and an outer diameter (r ₃ ) of 85 μm is formed, An element in which the height outside the groove is the same as the columnar region height of the surface having the light emitting region may be used. This is advantageous for handling in subsequent manufacturing processes, wire bonding when mounting elements, and the like.
[0037]
Note that although a case where there is one light-emitting region has been described in this embodiment mode, an element having a plurality of columnar light-emitting regions in one element may be used.
[0038]
Next, a semiconductor laser according to a second embodiment of the present invention will be described together with a manufacturing method. A sectional view of the semiconductor laser is shown in FIG.
[0039]
As shown in FIG. 3, the semiconductor laser according to the present embodiment has an n-type GaAs buffer layer 32 (thickness 120 nm, Si = 1 × 10 ¹⁸ cm ⁻³ ), n-type Al ₀ on an n-type GaAs substrate 31. _.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 33 (a stack of 40.5 periods with a high reflection film and a low reflection film having a thickness corresponding to a quarter wavelength as one period) , Si = 1 × 10 ¹⁸ cm ⁻³ ), undoped InGaP spacer layer 34, undoped InGaAsP quantum well layer (4 layers of 8 nm, oscillation wavelength 780 nm), and undoped InGaP barrier layer (3 layers of 5 nm thickness). Quantum well active layer 35, undoped InGaP spacer layer 36, undoped tensile strained InGaP spacer layer 37, p-type AlAs layer 38 (thickness corresponding to ¼ wavelength, C = × ¹⁰ 18 ^cm -3), p-type _Al 0.5 _{Ga 0.5} As spacer layer 39, p-type _{Al 0.9 Ga 0.1 As / Al 0.3} Ga 0.7 As upper semiconductor multilayer reflection film 40 (A high-reflection film having a thickness corresponding to a quarter wavelength and a low-reflection film with 29 periods stacked as one period, C = 2 × 10 ¹⁸ cm ⁻³ ), and a p-type GaAs contact layer 41 (thickness 10 nm, C = 1 × 10 ²⁰ cm ⁻³ ) are sequentially stacked by MOCVD.
[0040]
Next, the p-type contact layer 41 is removed by etching the upper part of the light emitting region. In order to form the oscillation region, a cylindrical region having a diameter of 30 μm is left, and its periphery is removed until the undoped tensile strained InGaP spacer layer 37 is exposed. By performing heat treatment (390 ° C., 8 minutes) in a furnace into which heated steam is introduced, the region 38a other than the current injection region of the p-type AlAs layer 38 is selectively oxidized to form a current confinement layer, and the diameter is 8 μm (r ₁ ) A non-oxidized region, that is, a current injection region is formed. A protective film 42 made of SiO ₂ is formed on a region formed into a cylindrical shape by etching, the protective film 42 in a region corresponding to the light emitting region is removed, and a p-side electrode 43 in which Ti / Pt / Au is laminated in this order. Then, the n-side electrode 44 formed by stacking AuGe / Ni / Au in this order is formed.
[0041]
The surface-emitting type semiconductor laser device of the present embodiment manufactured as described above has an n-type GaAs buffer layer 32, an n-type Al _0.9 Ga _0.1 As / Al _{0. 3} Ga _0.7 as lower semiconductor multilayer reflection film 33, an undoped InGaP spacer layer 34, a quantum well active layer 35 made of undoped InGaAsP quantum well layer and an undoped InGaP barrier layer, an undoped InGaP spacer layer 36, an undoped tensile strain InGaP spacer layer 37, a current confinement layer formed by oxidizing the region 38a other than the current injection region of the p-type AlAs layer 38, a p-type Al _0.5 Ga _0.5 As spacer layer 39, and a p-type Al _0.9 Ga _0.1 As. / _Al 0.3 _{Ga 0.7} As the product of the upper semiconductor multilayer reflection film 40 and the p-type GaAs contact layer 41 in this order A semiconductor layer formed by, becomes a pair of electrodes (n-side electrode 44 and the p-side electrode 43), p-type _{Al 0.9 Ga 0.1 As / Al 0.3} Ga 0.7 As upper semiconductor Laser light is emitted from the surface of the multilayer reflective film 40. n-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 33 and p-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As upper part Each of the semiconductor multilayer reflective films 40 is an optical resonator mirror, and the two mirrors constitute an optical resonator.
[0042]
Also in the surface emitting semiconductor laser element according to the present embodiment, the current confinement layer formed by selective oxidation by the undoped tensile strained InGaP spacer layer 37, as in the surface emitting semiconductor laser element according to the first embodiment. Since the compressive strain can be compensated, the active layer is not affected by the strain of the current confinement layer, so that high reliability can be obtained.
[0043]
In the above two embodiments, tensile strained InGaP is used as the strain compensation layer, but it may be composed of at least one of InGaAsP, AlGaInAsP, AlGaInP, GaAsP, and AlGaAsP. Note that the semiconductor has a composition having a strain opposite to the strain of the current confinement layer from the semiconductor according to the strain of the current confinement layer. In addition, in the case of containing Al, it is desirable to set the Al content so as not to form a band gap that becomes an electron barrier.
[0044]
According to the surface emitting semiconductor laser elements according to the above two embodiments, high reliability can be realized in the 780 nm band which is the low propagation loss wavelength region of POF.
[0045]
In addition, by setting the composition of the active layer to AlGaAs or InGaAsP to an appropriate elemental composition ratio, it is possible to select the oscillation wavelength in the range of 730 to 820 nm, and further in the wavelength range of 770 to 800 nm. High reliability can be obtained also by applying the present invention to the element.
[0046]
Further, according to the surface emitting semiconductor laser device of the present invention, it is possible to achieve high reliability in a VCSEL having a selective oxidation type or ion implantation type current confinement structure excellent in performance and mass productivity. It is possible to promote the practical use of high-speed optical fiber communication exceeding 1 Gbps in HDTV and the like.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a surface-emitting semiconductor laser device according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing a modification of the surface-emitting semiconductor laser device according to the first embodiment. Sectional view of a surface emitting semiconductor laser device according to a second embodiment of the present invention
11 n-type GaAs substrate 12 n-type GaAs buffer layer 13 n-type Al _0.9 Ga _0.1 As / Al _0.3 Ga _0.7 As lower semiconductor multilayer reflective film 14 undoped InGaP spacer layer 15 undoped Al _0.12 Ga Quantum well active layer 16 consisting of _0.88 As quantum well layer and undoped Al _0.3 Ga _0.7 As barrier layer Undoped Al _0.6 Ga _0.4 As spacer layer 17 Undoped InGaAsP tensile strain spacer layer 18 p-type Al _0.6 Ga _0.4 As spacer layer 19 p-type AlAs layer 19a Current confinement layer 20 p-type Al _0.6 Ga _0.4 As spacer layer 21 p-type Al _0.9 Ga _0.1 As / Al _{0. 3} Ga _0.7 As upper semiconductor multilayer reflective film 22 p-type GaAs contact layer 23 SiO ₂ protective film 24 Ti / Pt / Au P-side electrode 25 made of n-side electrode made of AuGe / Ni / Au

Claims (5)

A semiconductor layer in which an optical resonator mirror made of a lower semiconductor multilayer film, an active layer, a selective oxidation type or ion implantation type current confinement layer, and an optical resonator mirror made of an upper semiconductor multilayer reflective film are laminated in this order on a GaAs substrate. And a pair of electrodes for injecting current into the active layer, and a surface emitting semiconductor laser element that emits light from an end face parallel to the laminated surface of the semiconductor layer,
A surface emitting semiconductor laser device comprising a strain compensation layer for compensating for the strain of the current confinement layer between the active layer and the upper semiconductor multilayer reflective film. 2. The surface emitting semiconductor laser device according to claim 1, wherein the strain compensation layer is made of at least one of InGaP, InGaAsP, AlGaInAsP, AlGaInP, GaAsP, and AlGaAsP. The current confinement layer comprises a plurality of selectively oxidized layers;
3. The surface emitting semiconductor laser device according to claim 1, wherein the strain compensation layer is provided in a region sandwiched between the plurality of selectively oxidized layers. 4. The surface emitting semiconductor laser device according to claim 1, wherein an oscillation wavelength band of the laser beam is in a range from 730 nm to 820 nm. 4. The surface emitting semiconductor laser element according to claim 1, wherein an oscillation wavelength band of the laser beam is in a range from 770 nm to 800 nm.

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