JP2016213486A - Surface emitting semiconductor laser, surface emitting semiconductor laser device, optical transmission device, and information processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable surface emitting semiconductor laser with a long resonator.SOLUTION: A surface emitting semiconductor laser (VCSEL) 10 with a long resonator includes: a semi-insulating i-type GaAs substrate 100; a lower part DBR 102 comprising semi-insulating i-type AlGaAs; a semi-insulating i-type AlGaAs layer 110; a contact layer 112 comprising an n-type GaInP; an active region 114; a current constriction layer 120 comprising a p-type AlAs; an upper part DBR 106 comprising a p-type AlGaAs; a p-side electrode 130 formed on an apex of a mesa M; and an n-side electrode 140 electrically connected to the contact layer 112 exposed at a bottom of the mesa M.SELECTED DRAWING: Figure 1

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.

  Non-Patent Documents 1 and 2 disclose a surface-emitting type semiconductor laser of a selective oxidation type long resonator using a long monolithic cavity. Patent Document 1 discloses a surface-emitting type semiconductor laser having a long resonator in which a cavity extension region is interposed between mirrors.

H. J. Unold, el al, “Improving Single-Mode VCSEL Performance by Introducing a Long Monolithic Cavity”, IEEE, PHOTONICS TECHNOLOGY LETTERS, VOL. 12, NO. 8, AUGUST 2000 S. W. Z. Mahmoud, “Analysis of longitudinal mode wave guiding in vertical-cavity surface-emitting lasers with long monolithic cavity”, APPLIED PHYSICS LETTERS, VOL. 78, NUMBER 5 JP 2005-129960 A

  An object of the present invention is to provide a highly reliable surface emitting semiconductor laser.

Claim 1 is a substrate, a first semiconductor multilayer film reflecting mirror formed on the substrate, wherein a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a low refractive index are laminated, A semi-insulating i-type AlGaAs layer having an optical film thickness larger than an oscillation wavelength, and a layer functioning as a resonator extension region together with the i-type AlGaAs layer, formed on the first semiconductor multilayer film reflecting mirror. An n-type semiconductor layer formed on the i-type AlGaAs layer and having no deep level due to impurities or having a deep level higher than the Γ level and lattice-matched to the substrate; A p-type in which an active region formed on the n-type semiconductor layer and a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a low refractive index are stacked on the active region. The second semiconductor multilayer film reflector, and reaches the n-type semiconductor layer However, a columnar structure having a depth that does not reach the i-type AlGaAs layer is formed, and an n-side electrode is electrically connected to the n-type semiconductor layer. A surface emitting semiconductor laser having a p-side electrode electrically connected to the surface.
The surface emitting semiconductor laser according to claim 2, wherein the n-type semiconductor layer is made of n-type GaInP.
The surface emitting semiconductor laser according to claim 1, wherein the first semiconductor multilayer film reflecting mirror is a semi-insulating i-type.
According to a fourth aspect of the present invention, there is provided a resonator length defined by the first semiconductor multilayer reflector, the i-type AlGaAs layer, the n-type semiconductor layer, the active region, and the second semiconductor multilayer reflector. 4. The surface-emitting type according to claim 1, wherein the oscillation wavelength is greater than the oscillation wavelength, includes at least two resonance wavelengths in the reflection band of the resonator, and the selected resonance wavelength is oscillated. Semiconductor laser.
According to a fifth aspect of the present invention, in the surface emitting semiconductor laser according to any one of the first to fourth aspects, a current confinement layer is formed in the second semiconductor multilayer film reflecting mirror.
According to a sixth aspect of the present invention, the first semiconductor multilayer film reflecting mirror includes an AlGaAs layer having a relatively high Al composition and a pair of AlGaAs having a relatively low Al composition, and the second semiconductor multilayer film. 6. The surface emitting semiconductor laser according to claim 1, wherein the reflecting mirror includes an AlGaAs layer having a relatively high Al composition and a pair of AlGaAs having a relatively low Al composition.
7. The surface emitting semiconductor laser according to claim 1, wherein the n-type semiconductor layer is n-type AlGaInP.
8. The surface emitting semiconductor laser according to claim 1, wherein the n-type semiconductor layer is n-type AlGaAsP.
According to a ninth aspect of the present invention, there is provided a surface emitting semiconductor laser device comprising: the surface emitting semiconductor laser according to any one of the first to eighth aspects; and an optical member that receives light from the surface emitting semiconductor laser.
A tenth aspect of the present invention provides an optical transmission comprising the surface-emitting type semiconductor laser device according to the ninth aspect and a transmission means for transmitting a laser beam emitted from the surface-emitting type semiconductor laser device through an optical medium. apparatus.
An eleventh aspect of the present invention is the surface emitting semiconductor laser according to any one of the first to eighth aspects, condensing means for condensing a laser beam emitted from the surface emitting semiconductor laser on a recording medium, and the concentrating element. A mechanism for scanning the recording medium with the laser beam condensed by the optical means.

According to the first and sixth aspects, a highly reliable surface emitting semiconductor laser can be provided.
According to the second, third, seventh, and eighth aspects, generation of crystal defects can be suppressed as compared with n-type AlGaAs.
According to the fourth aspect of the present invention, a highly reliable surface emitting semiconductor laser having a long resonator structure can be provided.
According to the fifth aspect, it is possible to increase the output of light.
According to the ninth to eleventh aspects, it is possible to provide a surface emitting semiconductor laser device, an optical transmission device, and an information processing device having a highly reliable long resonator structure.

1 is a schematic cross-sectional view of a surface emitting semiconductor laser having a long resonator structure according to a first embodiment of the present invention. FIG. 2A is a diagram showing an energy band of AlGaAs, and FIG. 2B is a diagram showing an energy band for explaining the DX center of n-type AlGaAs. It is a schematic sectional drawing of the surface emitting semiconductor laser of the long resonator structure based on the 2nd Example of this invention. It is a schematic sectional drawing which shows the structure of the surface emitting semiconductor laser apparatus which mounted the optical member 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 to Fig.4 (a).

  Next, embodiments of the present invention will be described with reference to the drawings. 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. A surface-emitting type semiconductor laser used for such a light source improves the light output and ESD (Electro Static Discharge) resistance in a single transverse mode, while reducing the resistance value and heat dissipation. It is required to extend the life of

  In the selective oxidation type surface emitting semiconductor laser, a single transverse mode is obtained by reducing the oxidation aperture diameter of the current confinement layer to about 3 microns. However, if the oxidation aperture diameter is reduced, the resistance of the element is reduced. And the heat generation temperature also increases, and this shortens the service life. Further, if the oxidized aperture diameter is reduced, the light output is also reduced. Increasing the resonator length is considered as one method for realizing a high light output and a long life of the surface emitting semiconductor laser. A surface emitting semiconductor laser having a long resonator typically includes a cavity whose length is increased by about 3 to 4 microns (about 10 to 20 times the oscillation wavelength). As the resonator length increases, the difference in optical loss between the fundamental transverse mode with a small divergence angle and the higher-order transverse mode with a large divergence angle becomes large. You can get mode. In the case of a surface emitting semiconductor laser having a long resonator, the oxidation aperture diameter can be increased to about 8 microns, and the optical output can be increased to, for example, about 5 mW.

  In the following description, a surface-emitting type semiconductor laser having a selective oxidation type long resonator is illustrated, and the surface-emitting type 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 sectional view of a VCSEL of a long resonator according to a first embodiment of the present invention. As shown in the figure, the VCSEL 10 of the long resonator of this example is an undoped structure in which AlGaAs layers having different Al compositions are alternately stacked on a semi-insulating i-type GaAs substrate 100 which is not doped with impurities. An i-type (intrinsic) lower distributed Bragg reflector (hereinafter referred to as a DBR) 102, a resonator 104 that provides a long resonator structure, formed on the lower DBR 102, and formed on the resonator 104. A p-type upper DBR 106 in which AlGaAs layers having different Al compositions are alternately stacked is stacked. These semiconductor layers are preferably formed by MOCVD.

The i-type lower DBR 102 is formed by, for example, stacking a plurality of pairs of Al _0.9 Ga _0.1 As layers and Al _0.3 Ga _0.7 As layers, 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 in 40 cycles. The p-type upper DBR 106 is formed by stacking a plurality of pairs of p-type Al _0.9 Ga _0.1 As layers and Al _0.3 Ga _0.7 As layers, and the thickness of each layer is λ / 4n _r . There are 29 cycles stacked alternately. The carrier concentration after doping with carbon which is a p-type impurity is, for example, 3 × 10 ¹⁸ cm ⁻³ . Preferably, a contact layer made of p-type GaAs is formed on the uppermost layer of the upper DBR 106, and a current confinement layer 120 of p-type AlAs or AlGaAs is formed on the lowermost layer of the upper DBR 106 or inside thereof.

The resonator 104 includes an i-type AlGaAs layer 110 that is formed on the lower DBR 102 and is not doped with impurities, a contact layer 112 that is an n-type semiconductor layer formed on the AlGaAs layer 110, and a contact layer 112. And an active region 114 formed on the substrate. The active region 114 includes a quantum well active layer 114B sandwiched between upper and lower spacer layers 114A and 114C, and the thickness of the active region 114 is preferably equal to the oscillation wavelength λ. The lower spacer layer 114A is, for example, an undoped Al _0.6 Ga _0.4 As layer, and the quantum well active layer 114B is an undoped Al _0.11 Ga _0.89 As quantum well layer and an undoped Al _0.3 Ga _0.7. It is an As barrier layer, and the upper spacer layer 114C is an undoped Al _0.6 Ga _0.4 As layer.

  The AlGaAs layer 110 is a monolithic AlGaAs semiconductor layer formed by a series of epitaxial growth, and has an optical film thickness of any number, for example, several λ to several tens λ (λ is an oscillation wavelength). Since the AlGaAs layer 110 is an i-type semiconductor layer that is not doped with impurities, it does not form deep impurity levels like the DX center in n-type AlGaAs doped with impurities such as Si. Further, light absorption by the impurity dopant is also suppressed.

  The contact layer 112 is also made of a material lattice-matched to the GaAs substrate 100 by a series of epitaxial growths. Preferably, the contact layer 112 is made of n-type GaInP. GaInP does not form a DX center like n-type AlGaAs, or has a deep level due to impurities (DX center) higher than the Γ level, and therefore, fewer crystal defects are generated than n-type AlGaAs. Therefore, unlike the n-type AlGaAs, the active region 114 is not deteriorated due to crystal defects due to the occurrence of the DX center. Further, since GaInP has a high selection ratio with respect to GaAs and AlGaAs etchants, it can function as an etching stopper when the mesa M is formed on the substrate as will be described later. The contact layer 112 can also be configured using a material other than GaInP. For example, a material whose impurity level is shallower than the DX center level of n-type AlGaAs can be used. When such a material is used, the probability of occurrence of a DX center is reduced as compared with n-type AlGaAs, and the influence of the DX center can be reduced. For example, n-type AlGaInP or n-type AlGaAsP can be used.

  Since the contact layer 112 provides a current path between the n-side electrode 140 and the active region 114, the film thickness is selected so that the current resistance is not increased. Preferably, the resistance is reduced by setting the thickness of the contact layer 112 to be equal to or longer than the oscillation wavelength λ. The AlGaAs layer 110 and the contact layer 112 formed between the lower DBR 102 and the active region 114 constitute a resonator extension region, and the resonator extension region can also be referred to as a cavity extension region or a cavity space. Normally, a VCSEL without a long resonator does not include the resonator extension region 110, and usually forms an active region 106 on the lower DBR 102, and the optical film thickness of the resonator 104 is λ or less.

  By etching the semiconductor layer from the upper DBR 106 to the contact layer 112, a cylindrical mesa (columnar structure) M is formed on the substrate 100. As described above, when the contact layer 112 is made of GaInP, the GaInP has a high etching selectivity with respect to AlGaAs constituting the upper DBR 106, so that the mesa M can be stopped at the contact layer 112 with high accuracy.

  Due to the formation of the mesa M, the contact layer 112 is exposed at the bottom of the mesa M. Since GaInP does not contain Al, it is difficult to be oxidized even if the surface is exposed. In addition, the current confinement layer 120 in the upper DBR 106 is exposed on the side surface of the mesa M and is selectively oxidized in the oxidation process. Preferably, the current confinement layer 120 is located in the vicinity of the active region 114 and is made of p-type AlAs or AlGaAs having a very high Al composition (for example, Al composition is 98% or more). The current confinement layer 120 may replace the AlGaAs layer having a high Al composition in the upper DBR 106. The current confinement layer 120 includes an oxidized region 120A selectively oxidized from the side surface of the mesa M and a conductive region (oxidized aperture) 120B surrounded by the oxidized region 120A. A planar shape in a plane parallel to the main surface of the substrate 100 of the conductive region 120B is a circular shape reflecting the outer shape of the mesa M, and its center substantially coincides with the optical axis in the axial direction of the mesa M. In the VCSEL 10 of the long resonator, in order to obtain a fundamental transverse mode, the diameter of the conductive region 120B can be made larger than that of a normal VCSEL. For example, the diameter of the conductive region 120B is increased to about 7 to 8 microns, High output can be achieved.

  A metal annular p-side electrode 130 in which Au or Ti / Au is laminated is formed on the uppermost layer of the mesa M, and the p-side electrode 130 is ohmically connected to the contact layer of the upper DBR 106. The p-side electrode 130 is formed with a circular opening, that is, a light exit port 130A for emitting light, and the center of the light exit port 130A substantially coincides with the optical axis of the mesa M. On the contact layer 112 exposed at the bottom of the mesa M, a metal annular n-side electrode 140 in which Au or Ti / Au is laminated is formed. The n-side electrode 140 is electrically connected to the contact layer 112. Connected. The p-side electrode 130 and the n-side electrode 140 may be formed simultaneously by a lift-off process.

  In a VCSEL without a long resonator, when operating in a single transverse mode, it has one resonant wavelength, ie, one longitudinal mode, because the resonator length is short. On the other hand, in the VCSEL 10 having a long resonator as in the present embodiment, the resonator length becomes long, so that a plurality of resonance wavelengths can be generated. The number of resonant wavelengths generated is proportional to the size of the resonator length. For this reason, in a VCSEL with a long resonator, resonance wavelength switching (longitudinal mode switching) is likely to occur due to fluctuations in operating current, etc., and inflection points (kinks) occur in the IL characteristics that are the relationship between input current and laser output. There are things to do. Such switching of the resonance wavelength is not preferable for high-speed modulation of the VCSEL. Therefore, by reducing the refractive index difference of the pair of AlGaAs constituting the lower DBR 102 or the refractive index difference of the pair of AlGaAs constituting the upper DBR 106, It is desirable to narrow the reflection band at which the laser oscillation is possible (for example, 99% or more), select a desired resonance wavelength from a plurality of resonance wavelengths, and suppress longitudinal mode switching. The VCSEL 10 of the present embodiment outputs a single transverse mode laser beam of 780 nm, for example.

  FIG. 2A shows the energy band of the normal state (Γ level) of n-type AlGaAs, and FIG. 2B shows the energy band when a DX center is generated in n-type AlGaAs. . As shown in FIG. 2A, the electrons of the conductor generate light (photons) by being combined with holes in the valence band. On the other hand, in an n-type AlGaAs having an Al composition of approximately 20% or more, a deep level of the DX center lower than the Γ level of FIG. 2A is formed, and electrons are easily trapped in the DX center. At that time, the donor itself moves in the group IV donor, and Ga (Al) moves in the group VI donor. Electrons are accumulated in the DX center, and are released from the DX center by absorbing light and return to the conductor. At that time, the IV group donor is the donor itself, and the VI group donor is Ga (Al). Move. Thus, the DX center is a deep level formed on the conductor side, and is assumed to be an As defect generated by injecting an impurity serving as a donor into AlGaAs or GaAs.

  The VCSEL 10 of the long resonator of this embodiment uses an i-type AlGaAs layer 110 and an n-type GaInP contact layer 112 lattice-matched to the GaAs substrate 100 as the resonator extension region. Since the i-type AlGaAs layer 110 is not doped with impurities, it does not generate a DX center like n-type AlGaAs doped with impurities such as Si (FIG. 2B). In the n-type AlGaAs layer, a large number of DX centers, which are deep levels, are generated due to the influence of the Al composition and the doping concentration, and the density of crystal defects increases, resulting in the crystal structure of the active layer 114B. This is one of the causes that cause destruction and rapid deterioration and significant deterioration of characteristics.

  In addition, since n-type GaInP can be lattice-matched to the GaAs substrate 100, it can be formed by a series of epitaxial growth. Since n-type GaInP does not form a deep level (DX center) like n-type AlGaAs, the probability of occurrence of crystal defects is very small compared to n-type AlGaAs. Therefore, destruction of the crystal structure of the active layer 114B due to GaInP is suppressed. Although growth of GaInP is difficult compared to AlGaAs, GaInP only needs to function as a contact layer for the n-side electrode 140, and can be made smaller than the film thickness of the i-type AlGaAs layer 110.

  As described above, the VCSEL 10 of the long resonator according to the present embodiment does not contain n-type AlGaAs which essentially causes a DX center, so that the crystal structure of the active region 114 is destroyed or deteriorated due to crystal defects of the DX center. Therefore, a long-resonator VCSEL with a long lifetime and high reliability can be obtained.

  Next, FIG. 3 shows a schematic sectional view of a VCSEL of a long resonator according to the second embodiment of the present invention. The VCSEL 10A according to the second embodiment is configured using a p-type GaAs substrate 200. On the GaAs substrate 200, a p-type lower DBR 202 and resonators 204 in which AlGaAs layers having different Al compositions are alternately stacked, and semi-insulating i which is not doped with impurities in which AlGaAs layers having different Al compositions are alternately stacked. The upper DBR 206 of the mold is stacked.

  A p-side electrode 230 is formed on the back surface of the substrate 200, and the p-side electrode 230 is electrically connected to the lower DBR 202 via the substrate 200. In part of the lower DBR 202, a current confinement layer 220 is formed in the vicinity of the active region, and an oxidized region 220A selectively oxidized and a conductive region 220B surrounded by the oxidized region 220A are formed. The resonator 204 includes an active region 210 formed on the lower DBR 202, a contact layer 212 made of n-type GaInP formed on the active region 210, and an impurity doped on the contact layer 212. And an i-type AlGaAs layer 214 that is not formed. As in the first embodiment, the contact layer 212 has a film thickness equal to or greater than the oscillation wavelength λ, and the i-type AlGaAs layer 212 has a film thickness larger than that of the contact layer 212, and the sum of the two. The film thickness can be, for example, about 10 to 20λ.

  A mesa M is formed from the upper DBR 206 to the contact layer 212, the contact layer 212 is exposed at the bottom of the mesa M, and an annular n-side electrode 240 is formed on the contact layer 212. Further, a mesa M1 that exposes at least the current confinement layer 220 is formed below the mesa M, and the current confinement layer 220 is selectively oxidized from the side surface of the mesa M1.

  Also in the second embodiment, it is possible to obtain a VCSEL 10A having a long resonator that does not include a DX center made of n-type AlGaAs. As a modification of the second embodiment, as shown in FIG. 3B, the p-side surface electrode 230A may be formed on the lower DBR 202 exposed by the mesa M1. The p-side surface electrode 230A may be used in combination with the back surface electrode 230A, or may be used alone as shown in FIG. When only the p-side surface electrode 230A is formed, the substrate 200 may be semi-insulating i-type GaAs.

  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.

  In the above embodiment, the lower DBR 102/202 and the upper DBR 106/206 are configured by a pair of a high AlGaAs layer having a high Al composition ratio and a low AlGaAs layer having a low Al composition ratio, but the lower DBR 102/202 and the upper DBR 106/206 are It is not limited to AlGaAs. The lower DBR and the upper DBR may be configured by a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a low refractive index. For example, GaAs as a high refractive index layer and a low refractive index layer as a low refractive index layer. A combination of AlGaAs may be used. When the oscillation wavelength is long, GaAs can be used for the DBR.

  In the above embodiment, the optical film thickness of the resonator extension region 105 is 16λ. However, this is an example, and is selected from the range of 10λ to 20λ, for example. However, it should be noted that as the resonator length increases, the number of resonant wavelengths increases proportionally. Further, the refractive index difference (in this example, the difference in Al composition) between the high refractive index layer and the low refractive index layer constituting the lower DBR or the upper DBR is appropriately selected from the relationship with the resonance wavelength that can exist. That is, the refractive index difference is selected so that a reflection band can be obtained in which the reflectance at an undesired resonance wavelength is reduced. In addition, the diameter of the conductive region (oxidized aperture) of the current confinement layer 120/220 can be appropriately changed according to the required light output and the like. 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.

  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. 4A 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 long resonator 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 a stem 330 including the chip 310, and a ball lens 360 as an optical member is fixed in an opening 352 at the center 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. 4B 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. 4B 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. 5 is a diagram illustrating an example in which a VCSEL is applied to a light source of an optical information processing apparatus. As shown in FIG. 4A or FIG. 4B, the optical information processing device 370 includes a collimator lens 372 that receives laser light from the surface-emitting type semiconductor laser device 300 or 302 on which the long resonator VCSEL is mounted. The polygon mirror 374 that rotates at a speed and reflects the light beam from the collimator lens 372 at a certain spread angle, the fθ lens 376 that receives the laser light from the polygon mirror 374 and irradiates the reflection mirror 378, and the line-shaped reflection mirror 378. A photosensitive drum (recording medium) 380 that forms a latent image based on the reflected light from the reflecting mirror 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. 6 is a cross-sectional view showing a configuration when the surface-emitting type semiconductor laser device shown in FIG. 4A 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.

10, 10A, 10B: Long resonator VCSEL
100: Substrate 102: Lower DBR
104: Resonator 106: Upper DBR
110: AlGaAs layer 112: contact layer 114: active region 114A: lower spacer layer 114B: active layer 114C: upper spacer layer 120: current confinement layer 130: p-side electrode 130A: light exit port 140: n-side electrode 200: substrate 202 : Lower DBR
204: Resonator 206: Upper DBR
210: active region 212: contact layer 214: AlGaAs layer 220: current confinement layer 230: p-side electrode 240: n-side electrode

Claims (11)

A substrate,
A first semiconductor multilayer reflector formed by stacking a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a low refractive index formed on the substrate;
A semi-insulating i-type AlGaAs layer formed on the first semiconductor multilayer reflector and having an optical film thickness greater than the oscillation wavelength;
A layer that functions as a resonator extension region together with the i-type AlGaAs layer, and is formed on the i-type AlGaAs layer and does not have a deep level due to impurities, or has a deep level higher than the Γ level. An n-type semiconductor layer lattice-matchable to the substrate;
An active region formed on the n-type semiconductor layer;
A p-type second semiconductor multilayer film reflecting mirror formed on the active region, in which a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a low refractive index are stacked;
A columnar structure having a depth reaching the n-type semiconductor layer but not reaching the i-type AlGaAs layer is formed,
An n-side electrode is electrically connected on the n-type semiconductor layer,
A surface emitting semiconductor laser in which a p-side electrode is electrically connected to the first semiconductor multilayer film reflecting mirror. The surface emitting semiconductor laser according to claim 1, wherein the n-type semiconductor layer is made of n-type GaInP. The surface emitting semiconductor laser according to claim 1, wherein the first semiconductor multilayer film reflecting mirror is a semi-insulating i-type. The length of the resonator defined by the first semiconductor multilayer reflector, the i-type AlGaAs layer, the n-type semiconductor layer, the active region, and the second semiconductor multilayer reflector is longer than the oscillation wavelength. 4. The surface-emitting type semiconductor laser according to claim 1, wherein the surface-emitting type semiconductor laser includes at least two resonance wavelengths within a reflection band of the resonator and oscillates at a selected resonance wavelength. 5. The surface emitting semiconductor laser according to claim 1, wherein a current confinement layer is formed in the second semiconductor multilayer film reflecting mirror. The first semiconductor multilayer film reflector includes an AlGaAs layer having a relatively high Al composition and an AlGaAs pair having a relatively low Al composition, and the second semiconductor multilayer film reflector has a relative 6. The surface emitting semiconductor laser according to claim 1, comprising a pair of an AlGaAs layer having a relatively high Al composition and a pair of AlGaAs having a relatively low Al composition. The surface emitting semiconductor laser according to claim 1, wherein the n-type semiconductor layer is n-type AlGaInP. The surface emitting semiconductor laser according to claim 1, wherein the n-type semiconductor layer is n-type AlGaAsP. A surface-emitting type semiconductor laser according to any one of claims 1 to 8,
An optical member that receives light from the surface-emitting type semiconductor laser; and
A surface emitting semiconductor laser device comprising: A surface-emitting type semiconductor laser device according to claim 9,
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 type semiconductor laser according to any one of claims 1 to 8,
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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