JP5434421B2 - Surface emitting semiconductor laser, surface emitting semiconductor laser device, optical transmission device, and information processing device - Google Patents

Description

  The present invention relates to a surface emitting semiconductor laser, a surface emitting semiconductor laser device, an optical transmission device, and an information processing device.

  A surface emitting semiconductor laser (VCSEL: Vertical Cavity Surface Emitting Laser) is used as a light source of a communication apparatus or an image forming apparatus. These devices often include polarization-dependent optical devices such as polarization beam splitters, and surface-emitting semiconductor lasers are required to have stable polarization control of laser light. Controlling the polarization direction by giving anisotropy to the shape of the DBR with respect to the optical axis (Patent Document 1), and controlling the polarization direction by providing a grating structure on the surface of the reflecting mirror constituting the vertical resonator (Patent Document 2) and the like are disclosed.

JP 2008-28120 A Japanese Patent Laid-Open No. 5-21889

  An object of this invention is to provide the surface emitting semiconductor laser which can control a polarization direction.

The surface-emitting type semiconductor laser according to claim 1 is formed on a substrate, a first semiconductor multilayer reflector of the first conductivity type formed on the substrate, and the first semiconductor multilayer reflector. Active region, a second semiconductor multilayer reflector of the second conductivity type formed on the active region, and light emission formed on the second semiconductor multilayer reflector and emitting laser light A current confinement comprising a metal member defining a mouth on the second semiconductor multilayer film reflector, an oxidized region formed on the active region and selectively oxidized, and a conductive region surrounded by the oxidized region A layer and a material transparent to the oscillation wavelength of the laser beam, having anisotropy in the longitudinal direction and the short side direction in a plane parallel to the main surface of the substrate, and the light exit opening partially And the length of the insulating film in the longitudinal direction is the conductive film. And the length of the insulating film in the short direction is smaller than the diameter of the conductive region, and the insulating film is formed in the second direction. the reflectance of the semiconductor multilayer reflector, wherein the insulating film is much larger than the reflectivity of the second semiconductor multilayer reflector which is not formed, the metal member and the insulating film, the second semiconductor multilayer film Formed on the top layer of the reflector .
3. The end surface of the uppermost layer of the second semiconductor multilayer film reflecting mirror is a node of a standing wave of laser light, and the end surface of the insulating film is an antinode of the standing wave of laser light. To be.
4. The optical film thickness of the insulating film according to claim 3, wherein the optical film thickness is an odd multiple of 1/4 of the oscillation wavelength of the laser beam.
5. The conductive region according to claim 4, wherein the conductive region has a circular shape, and the light emission port has a circular shape.
6. The light emitting port according to claim 5, wherein at least a region of the light emission port is covered with a protective film, and the film thickness of the protective film is a change in reflectance difference of the second semiconductor multilayer film reflecting mirror depending on the presence or absence of the insulating film. Is adjusted to be small.
A semiconductor laser device according to a sixth aspect mounts the surface-emitting type semiconductor laser according to any one of the first to fifth aspects and an optical member that receives light from the surface-emitting type semiconductor laser.
According to a seventh aspect of the present invention, there is provided an optical transmission device comprising: the surface emitting semiconductor laser device according to the sixth aspect; and a transmission unit that transmits the laser light emitted from the surface emitting semiconductor laser device through an optical medium. Prepare.
An information processing apparatus according to an eighth aspect of the present invention includes a surface emitting semiconductor laser according to any one of the first to fifth aspects, and a condensing unit that condenses a laser beam emitted from the surface emitting semiconductor laser onto a recording medium. And a mechanism for scanning the laser beam condensed by the condensing unit on the recording medium.

According to the first aspect, the polarization direction of the laser light can be controlled in the longitudinal direction of the insulating film.
According to the second aspect, the difference in reflectance of the second semiconductor multilayer film reflecting mirror depending on the presence or absence of the insulating film can be maximized.
According to the third aspect, it is possible to increase the reflectance of the second semiconductor multilayer film reflecting mirror on which the insulating film is formed.
According to the fourth aspect, the polarization direction of the circular laser beam can be controlled.
According to the fifth aspect, compared with the case where the thickness of the protective film is not adjusted, the difference in reflectance of the second semiconductor multilayer film reflecting mirror depending on the presence or absence of the insulating film can be increased.
According to the sixth to eighth aspects, it is possible to provide a surface emitting semiconductor laser device, an optical transmission device, and an information processing device using a surface emitting semiconductor laser whose polarization direction is controlled.

1 is a schematic plan view, a cross-sectional view taken along line XX, and a cross-sectional view taken along line YY of a surface-emitting type semiconductor laser according to a first embodiment of the present invention. FIG. 2 is a plan view for explaining a relationship among a light emitting port, a current confinement layer, and an insulating film of the surface emitting semiconductor laser shown in FIG. It is a graph which shows the insulating film film thickness dependence of the reflectance of upper DBR. It is a figure which shows the relationship between the standing wave of a laser beam, the termination | terminus surface of upper DBR, and the film thickness of an insulating film. It is a schematic plan view of the surface emitting semiconductor laser according to the second embodiment of the present invention. It is a schematic plan view of the surface emitting semiconductor laser according to the third embodiment of the present invention. FIG. 6 is a schematic plan view, a cross-sectional view taken along line XX, and a cross-sectional view taken along line YY of a surface-emitting type semiconductor laser according to a fourth embodiment of the present invention. It is a schematic sectional drawing which shows the structure of the surface emitting semiconductor laser apparatus which mounted the optical component in the surface emitting semiconductor laser of a present Example. It is a figure which shows the structural example of the light source device which uses the surface emitting semiconductor laser of a present Example. It is a schematic sectional drawing which shows the structure of the optical transmission apparatus using the surface emitting semiconductor laser apparatus shown in FIG.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description, a selective oxidation type surface emitting semiconductor laser is illustrated, and the surface emitting semiconductor laser is referred to as a VCSEL. It should be noted that the scale of the drawings is emphasized for easy understanding of the features of the invention and is not necessarily the same as the scale of an actual device.

  FIG. 1 is a schematic plan view, a sectional view taken along line XX, and a sectional view taken along line YY of a VCSEL according to a first embodiment of the present invention. The VCSEL 10 of this embodiment includes an n-type distributed black reflector (hereinafter referred to as DBR) 102 in which AlGaAs layers having different Al compositions are alternately stacked on an n-type GaAs substrate 100, and an upper portion and a lower portion. An active region 104 including a quantum well layer sandwiched between spacer layers and a p-type upper DBR 106 in which AlGaAs layers having different Al compositions formed on the active region 104 are alternately stacked are stacked.

The n-type lower DBR 102 is, for example, a multi-layer stack of an Al _0.9 Ga _0.1 As layer and an Al _0.3 Ga _0.7 As layer, and the thickness of each layer is λ / 4n _r (where λ is the oscillation wavelength, and n _r is The refractive index of the medium), and these are alternately laminated with a period of 40.5. The carrier concentration after doping silicon, which is an n-type impurity, is 3 × 10 ¹⁸ cm ⁻³ .

The lower spacer layer of the active region 104 is an undoped Al _0.6 Ga _0.4 As layer, and the quantum well active layer 5 is an undoped Al _0.11 Ga _0.89 As quantum well layer and an undoped Al _0.3 Ga _{0. 7} As barrier layer and the upper spacer layer is an undoped Al _0.6 Ga _0.4 As layer.

The p-type upper DBR 106 is, for example, a laminate of an Al _0.9 Ga _0.1 As layer and a p-type Al _0.3 Ga _0.7 As layer, and the thickness of each layer is λ / 4n _r (where λ is the oscillation wavelength, n _r Is the refractive index of the medium), and these are alternately laminated for 30 periods. The carrier concentration after doping with carbon which is a p-type impurity is 3 × 10 ¹⁸ cm ⁻³ . A contact layer 108 made of p-type GaAs is formed on the uppermost layer of the upper DBR 106, and a current confinement layer 110 made of p-type AlAs is formed on the lowermost layer of the upper DBR 106 or inside thereof. The carrier concentration of the contact layer 108 is, for example, 1 × 10 ¹⁹ cm ⁻³ .

Although not shown in FIG. 1, in order to reduce the series resistance of the laser element, an Al _0.9 Ga _0.1 As layer and an Al _0.3 Ga _0.7 As layer are formed in the p-type upper DBR 106 and / or the n-type lower DBR 102. An intermediate layer (graded layer) having an intermediate GaAs / AlAs mixed crystal ratio may be inserted.

  By etching the semiconductor layer from the upper DBR 106 to the lower DBR 102, a cylindrical mesa (columnar structure) M is formed on the substrate 100. The current confinement layer 110 includes an oxidized region 110A that is exposed on the side surface of the mesa M and is selectively oxidized from the side surface, and a conductive region (oxidized aperture) 110B that is surrounded by the oxidized region 110A. In the oxidation process of the VCSEL, the AlAs layer has a higher oxidation rate than the AlGaAs layer, and the AlAs layer is oxidized from the side surface of the mesa M toward the inside at a substantially constant rate. For this reason, the planar shape in a plane parallel to the main surface of the substrate 100 of the conductive region 110B is a circular shape reflecting the outer shape of the mesa M, and its center defines the optical axis in the axial direction of the mesa M. In the present embodiment, the diameter of the conductive region 110B is preferably about 5 μm or less so that single mode laser light is emitted.

  On the GaAs contact layer 108, a metal annular p-side electrode 112 in which Ti / Au or the like is laminated is formed, and the p-side electrode 112 is ohmically connected to the contact layer 108. The circular opening at the center of the p-side electrode 112 serves as a light emission port 112A that emits laser light. The center of the light exit port 112A substantially coincides with the optical axis of the mesa M. An n-side electrode 114 is formed on the back surface of the substrate 100. The VCSEL 10 of this embodiment emits single mode laser light having an oscillation wavelength of about 850 nm from the light exit port 112A when a forward drive current is applied between the p-side electrode 112 and the n-side electrode 114.

  What is characteristic in this embodiment is that a transparent insulating film 120 having an anisotropic shape is formed on the top of the mesa M. The insulating film 120 partially covers the light emission port 112A so that a reflectance distribution can be formed inside the conductive region 110B of the current confinement layer 110 only in the X-axis direction. FIG. 2 is a plan view for explaining the relationship among the dimensions of the insulating film 120, the conductive region 110B, and the light emission port 112A.

  The insulating film 120 is made of an insulating film transparent to the oscillation wavelength, preferably SiON. When the length in the short direction (X-axis direction) of the insulating film 120 is Lx and the length in the long direction (Y-axis direction) is Ly, the anisotropy has a relationship of Lx <Ly. The plane arrow of the light exit port 112A is circular, the diameter is D1, the plane arrow of the current confinement layer 110 is circular, and the diameter of the conductive region 110B is D2 (D1> D2). The length Ly in the longitudinal direction of the insulating film 120 is larger than the diameter D2 of the conductive region and larger than the diameter of the light exit port 112A (Ly> D1> D2). The length Lx in the short direction of the insulating film 120 is smaller than the diameter D2 of the conductive region 110B (Lx <D2).

  The rectangular insulating film 120 is formed such that its center (in this case, the intersection of diagonal lines) substantially coincides with the optical axis C. Therefore, a pair of uncovered regions 130 that are not covered with the insulating film 120 are formed inside the conductive region 110B in the X-axis direction in the light exit port 112A. On the other hand, the conductive region 110B in the Y-axis direction in the light exit port 112A is completely covered with the insulating film 120. In this way, the light emitting port 112A is partially covered with the anisotropic insulating film 120, thereby forming the region 130 where the insulating film 120 is not covered inside the conductive region 110B. The polarization direction of the laser light is controlled in the Y-axis direction.

Next, the principle of polarization control of this embodiment will be described with reference to FIGS. FIG. 3 is a graph showing the dependency of the p-type upper DBR reflectance on the insulating film, where the vertical axis represents the reflectance of the upper DBR 106 and the horizontal axis represents the optical film thickness of the insulating film. Here, the insulating film 120 is SiON, and its refractive index n is n = 1.6. In this embodiment, as shown in FIG. 4A, the length of the upper DBR 106 in the optical axis direction is such that the uppermost termination surface S (here, the termination surface of the GaAs contact layer 108) It has been adjusted to match the standing wave section. Since each layer of the upper DBR 106 has a film thickness of λ / 4n _r , the entire length of the upper DBR 106 in the optical axis direction may be a multiple of the half wavelength (λ / 2) of the laser light. Alternatively, the thickness of the uppermost GaAs contact layer 108 may be adjusted so that the end surface S of the contact layer 108 matches the node.

  As shown in FIG. 3, when the insulating film 120 is not formed on the upper DBR 106, the reflectance of the upper DBR 106 is about 0.976. When the film thickness is indicated by the arrow in FIG. 3, the multi-layer reflecting mirror including the insulating film 120 becomes the matching condition. That is, when the film thickness of the insulating film 120 is λ / 4 of the wavelength in the medium or an odd multiple thereof, the reflectance of the upper DBR 106 has a peak of about 0.988. As shown in FIG. 4B, when the thickness of the insulating film 120 is λ / 4 (or an odd multiple thereof), the termination surface S of the insulating film 120 coincides with the antinode of the standing wave of the laser light. In this way, by increasing the reflectance difference of the upper DBR 106 with or without the insulating film 120, oscillation of the region without the insulating film 120, that is, the uncovered region 130 can be suppressed. That is, in the region where the insulating film 120 does not exist, the reflectivity of the DBR becomes small, and as a result, the threshold current becomes large and oscillation becomes difficult. On the other hand, the region where the insulating film 120 exists has a high DBR reflectivity, and as a result, the threshold current becomes small and oscillation tends to occur. Therefore, the laser beam emitted from the light exit port 112A is circular, but its polarization direction is controlled in the Y-axis direction. The examples shown in FIGS. 4A and 4B are the most effective examples of the present invention.

  Next, a second embodiment of the present invention will be described. FIG. 5 is a schematic plan view of a VCSEL according to the second embodiment of the present invention. In the VCSEL 10A of the second embodiment, a part of the light emission port 112A is covered with a diamond-shaped insulating film 120A (indicated by hatching for easy understanding). The insulating film 120A has a rhombus shape and anisotropy in which the lengths of the major axis and the minor axis are different. An annular p-side electrode 112 (shown by hatching for easy understanding) is formed on the top of the mesa M, and a circular light emission port 112A is formed at the center thereof. The width of the insulating film 120A in the short axis direction (X axis) is smaller than the diameter D2 of the conductive region 110B, and the width of the insulating film 120A in the long axis direction (Y axis) is the diameter D2 of the conductive region 110B and the light exit port. It is larger than the diameter D1 of 112A. The center of the insulating film 120A is formed so as to substantially coincide with the optical axis C. As a result, a pair of uncovered regions 130A that are not covered by the insulating film 120A are formed inside the conductive region 110B in the light exit port 112A. . Also in the second embodiment, a reflectance distribution is formed inside the conductive region 110B by the anisotropic insulating film 120A, and the circular laser beam is polarization-controlled in the Y-axis direction.

  Next, a third embodiment of the present invention will be described. FIG. 6 is a schematic plan view of a VCSEL according to the third embodiment of the present invention. In the VCSEL 10B according to the third embodiment, the mesa M has an elliptical structure. The shape of the mesa M viewed from a plane parallel to the main surface of the substrate is an ellipse, and its short axis coincides with the X-axis direction and its long axis coincides with the Y-axis direction. The conductive region 110 </ b> B of the current confinement layer 110 has an elliptical shape reflecting the outer shape of the mesa M. An annular p-side electrode (indicated by hatching) is formed on the top of the mesa M, and a circular light emission port 112A is formed at the center thereof. An anisotropic (rectangular) insulating film 120B (indicated by hatching) having different lengths in the longitudinal direction and the short direction is formed so as to cover a part of the light exit port 112A. The length in the short direction of the insulating film 120B is smaller than the length in the short axis direction of the conductive region 110B, and the length in the long direction of the insulating film 120B is the length in the long axis direction of the conductive region 110B and the light emitting port. It is larger than the diameter of 112A. Similar to the first and second embodiments, the insulating film 120B is formed so that the center thereof coincides with the optical axis, and as a result, the insulating film 120B covers the inside of the conductive region 110B in the light emitting port 112A. An uncovered uncovered region 130B (unhatched portion) is formed.

  In the third embodiment, the mesa M has an elliptical structure having anisotropy, and since the conductive region 110B of the current confinement layer 110 has an elliptical shape, the laser light is polarized in the Y-axis direction by the anisotropy of the mesa itself. Be controlled. In addition, since the reflectance difference of the upper DBR 106 is formed depending on the presence or absence of the insulating film 120B, the polarization direction of the laser light is more stably controlled in the Y-axis direction.

  Next, a fourth embodiment of the present invention will be described. FIG. 7 is a schematic plan view of a VCSEL according to a fourth embodiment of the present invention, a sectional view taken along line XX, and a sectional view taken along line YY. The VCSEL 10C according to the fourth embodiment has a protective film 150 (hatched display in a plan view for easy understanding) for protecting the light exit port 112A in addition to the configuration of the first embodiment. The protective film 150 may cover at least a region exposed by the insulating film 120, or may cover the entire light emission port 112 </ b> A including the insulating film 120. Preferably, the protective film 150 is configured so that the reflectance at the center of the emission port where the insulating film 120 is formed is maximized, or the difference in the reflectance of the DBR obtained by the insulating film 120 is not as small as possible (for example, , Uniform film thickness), its film thickness and material are adjusted. Further, the protective film 150 may be an insulating film made of the same material as the insulating film 120 or may be made of a different material.

  Next, a preferred configuration of the VCSEL described in the first embodiment and a manufacturing process thereof will be exemplified. The VCSEL is manufactured using metal organic chemical vapor deposition (MOCVD), and an n-type lower DBR 102, an active region 104, and a p-type upper DBR 106 are sequentially stacked on an n-type GaAs substrate 100. The film thickness of each DBR layer is formed to be ¼ of the wavelength in the medium. In the upper DBR 106, a current confinement layer 110 made of p-type AlAs is inserted in the vicinity of the active region 104, and a p-type GaAs contact layer 108 is formed on the uppermost layer of the upper DBR 106.

  Next, the semiconductor layer on the substrate is etched using a known photolithography process, and a cylindrical mesa M is formed on the substrate. Next, oxidation treatment is performed to form an oxidized region 110A and a conductive region 110B surrounded by the oxidized region 110A in the current confinement layer 110. The diameter of the conductive region 110B is preferably set to 5 μm or less.

  Next, an annular p-side electrode 112 is formed on the contact layer 108 by a lift-off process. However, the p-side electrode 112 may be formed on the contact layer 108 before the mesa M is formed. Next, a SiON film is formed on the entire surface of the substrate including the mesa by CVD, and the anisotropic insulating film 120 is formed on the light emitting port by etching the SiON film. Then, the VCSEL as shown in FIG. 1 can be obtained by forming the n-side electrode 114 on the back surface of the substrate.

  Although various examples have been shown in the first to fourth embodiments, the present invention is not limited to these examples. For example, in the above embodiment, the mesa is formed on the substrate and the oxidized region 110A is formed in the mesa by the oxidation process. However, it is not always necessary to use the current confinement layer by the oxidation process. For example, proton ion implantation may be performed in the DBR layer stacked on the substrate to form an annular electrically insulating region in the current confinement layer. In this case, it is not necessary to form a mesa on the substrate.

The insulating film transparent to the oscillation wavelength is not limited to the above-described SiON, and other insulating films or dielectric films such as SiO ₂ , SiNx, and TiO ₂ can be used. These film thicknesses are appropriately selected in relation to the material of the semiconductor layer constituting the upper DBR. Further, the shape of the insulating film can be rectangular, rectangular, rhombus, oval, etc. In short, the planar shape of the insulating film is such that there is a difference between the longitudinal direction and the short side with respect to the center. Any shape is acceptable.

  In the above-described embodiment, an example in which the termination surface of the upper DBR coincides with the node of the standing wave of the laser beam and the termination surface of the insulating film 120 coincides with the antinode of the standing wave is shown, but the present invention is not limited thereto. It is not something. The end surface of the DBR may coincide with a portion other than the node, and the end surface of the insulating film may coincide with a portion other than the antinode. In short, the reflectance of the DBR including the insulating film does not include the insulating film. What is necessary is just to become higher than the reflectance of DBR.

Furthermore, in the said Example, although mesa M illustrated the cylindrical shape or the elliptical structure, this is an example and a rectangular parallelepiped shape may be sufficient as it. Furthermore, the shape of the light exit port is exemplified as a circular shape, but may be an elliptical shape in addition to this. Furthermore, although the light emission port is formed by the p-side electrode, the light emission port may be formed using another metal or the like. Furthermore, the Al composition ratio of the DBR shown in the above embodiment is an example, and the Al composition ratio can be appropriately selected according to the purpose and application. Furthermore, although the AlGaAs-based VCSEL has been exemplified in the above-described embodiment, a VCSEL using another III-V group compound semiconductor may be used. Furthermore, in the above embodiment, a single spot VCSEL is illustrated, but a multi-spot VCSEL or VCSEL array in which a number of mesas (light emitting portions) are formed on a substrate may be used. In addition to AlAs, AlGaAs having a high Al composition such as Al _0.98 Ga _0.02 As may be used as the current confinement layer.

  Next, a surface-emitting type semiconductor laser device, an optical information processing device, and an optical transmission device using the VCSEL of this embodiment will be described with reference to the drawings. FIG. 8A is a cross-sectional view showing a configuration of a surface emitting semiconductor laser device in which a VCSEL and an optical member are mounted (packaged). In the surface emitting semiconductor laser device 300, the chip 310 on which the VCSEL is formed is fixed on the disk-shaped metal stem 330 via the conductive adhesive 320. Conductive leads 340 and 342 are inserted into through holes (not shown) formed in the stem 330, one lead 340 is electrically connected to the n-side electrode of the VCSEL, and the other lead 342 is It is electrically connected to the p-side electrode.

  A rectangular hollow cap 350 is fixed on the stem 330 including the chip 310, and an optical member such as a ball lens 360 is fixed in the central opening 352 of the cap 350. The optical axis of the ball lens 360 is positioned so as to substantially coincide with the center of the chip 310. When a forward voltage is applied between the leads 340 and 342, laser light is emitted from the chip 310 in the vertical direction. The distance between the chip 310 and the ball lens 360 is adjusted so that the ball lens 360 is included within the spread angle θ of the laser light from the chip 310. Further, a light receiving element or a temperature sensor for monitoring the light emission state of the VCSEL may be included in the cap.

  FIG. 8B is a diagram showing the configuration of another surface-emitting type semiconductor laser device. The surface-emitting type semiconductor laser device 302 shown in FIG. 8B has an opening at the center of the cap 350 instead of using the ball lens 360. A flat glass 362 is fixed in the 352. The center of the flat glass 362 is positioned so as to substantially coincide with the center of the chip 310. The distance between the chip 310 and the flat glass 362 is adjusted so that the opening diameter of the flat glass 362 is equal to or greater than the spread angle θ of the laser light from the chip 310.

  FIG. 9 is a diagram illustrating an example in which the VCSEL is applied to the light source of the optical information processing apparatus. As shown in FIG. 8A or FIG. 8B, the optical information processing device 370 rotates at a constant speed with a collimator lens 372 that receives laser light from the surface emitting semiconductor laser device 300 or 302 on which the VCSEL is mounted. The polygon mirror 374 that reflects the light beam from the collimator lens 372 with a certain spread angle, the fθ lens 376 that receives the laser light from the polygon mirror 374 and irradiates the reflection mirror 378, the line-shaped reflection mirror 378, and the reflection mirror A photosensitive drum (recording medium) 380 that forms a latent image based on reflected light from 378 is provided. As described above, optical information processing such as a copying machine or a printer provided with an optical system for condensing the laser light from the VCSEL on the photosensitive drum and a mechanism for scanning the condensed laser light on the optical drum. It can be used as a light source for the apparatus.

  FIG. 10 is a cross-sectional view showing a configuration when the surface-emitting type semiconductor laser device shown in FIG. 8A is applied to an optical transmission device. The optical transmission device 400 includes a cylindrical housing 410 fixed to the stem 330, a sleeve 420 integrally formed on the end surface of the housing 410, a ferrule 430 held in the opening 422 of the sleeve 420, and a ferrule 430. The optical fiber 440 to be held is included. An end of the housing 410 is fixed to a flange 332 formed in the circumferential direction of the stem 330. The ferrule 430 is accurately positioned in the opening 422 of the sleeve 420 and the optical axis of the optical fiber 440 is aligned with the optical axis of the ball lens 360. The core wire of the optical fiber 440 is held in the through hole 432 of the ferrule 430.

  The laser light emitted from the surface of the chip 310 is collected by the ball lens 360, and the collected light is incident on the core wire of the optical fiber 440 and transmitted. Although the ball lens 360 is used in the above example, other lenses such as a biconvex lens and a plano-convex lens can be used. Further, the optical transmission device 400 may include a drive circuit for applying an electrical signal to the leads 340 and 342. Furthermore, the optical transmission device 400 may include a reception function for receiving an optical signal via the optical fiber 440.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment, and various modifications can be made within the scope of the present invention described in the claims. Deformation / change is possible.

10: VCSEL
100: Substrate 102: Lower DBR
104: Active region 106: Upper DBR
108: contact layer 110: current confinement layer 110A: oxidized region 110B: conductive region 112: p-side electrode 112A: exit port 114: n-side electrode 120, 120A: insulating film 130, 130A: uncovered region 150: protective film S: End surface

Claims (8)

A substrate,
A first conductivity type first semiconductor multilayer film reflecting mirror formed on the substrate;
An active region formed on the first semiconductor multilayer reflector;
A second semiconductor multilayer reflector of the second conductivity type formed on the active region;
A metal member which is formed on the second semiconductor multilayer film reflecting mirror and which defines a light emitting port for emitting laser light on the second semiconductor multilayer film reflector;
A current confinement layer formed on the active region and having an oxidized region selectively oxidized and a conductive region surrounded by the oxidized region;
Insulating which is made of a material transparent to the oscillation wavelength of the laser beam, has anisotropy in the longitudinal direction and the short side direction in a plane parallel to the main surface of the substrate, and partially covers the light exit port And having a membrane
The length of the insulating film in the longitudinal direction is larger than the diameter of the conductive region in a plane parallel to the main surface of the substrate, and the length of the insulating film in the short direction is the diameter of the conductive region. less than the reflectivity of the second semiconductor multilayer reflector, wherein the insulating film is formed, the insulating film is much larger than the reflectivity of the second semiconductor multilayer reflector that is not formed,
The surface emitting semiconductor laser , wherein the metal member and the insulating film are formed on an uppermost layer of a second semiconductor multilayer film reflecting mirror . The termination surface of the uppermost layer of the second semiconductor multilayer film reflector is a node of a standing wave of laser light, and the termination surface of the insulating film is an antinode of the standing wave of laser light, The surface emitting semiconductor laser according to claim 1. 3. The surface emitting semiconductor laser according to claim 1, wherein the optical film thickness of the insulating film is an odd multiple of ¼ of the oscillation wavelength of the laser beam. 4. The surface emitting semiconductor laser according to claim 1, wherein the conductive region has a circular shape, and the light emission port has a circular shape. 5. At least the region of the light exit opening is covered with a protective film, and the film thickness of the protective film is such that the change in the difference in reflectance of the second semiconductor multilayer film reflecting mirror due to the presence or absence of the insulating film is small. The surface emitting semiconductor laser according to claim 1, wherein the surface emitting semiconductor laser is adjusted. A surface-emitting type semiconductor laser according to any one of claims 1 to 5,
An optical member that receives light from the surface-emitting type semiconductor laser; and
A surface emitting semiconductor laser device mounted with a laser. A surface-emitting type semiconductor laser device according to claim 6;
Transmission means for transmitting laser light emitted from the surface-emitting type semiconductor laser device through an optical medium;
An optical transmission device comprising: A surface emitting semiconductor laser according to any one of claims 1 to 5,
Condensing means for condensing the laser light emitted from the surface emitting semiconductor laser onto a recording medium;
A mechanism for scanning the recording medium with the laser beam condensed by the condensing means;
An information processing apparatus.

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