JP2006147751A - Optical semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical semiconductor device that is reduced in thickness along the emitting direction of laser light without requiring any large mirror for reflecting laser light and, in addition, does not require many components at the time of forming an optical pickup. <P>SOLUTION: On the bottom face of a package 14 having an opening 14a, a semiconductor laser element 11 is provided through a sub-mount 12. The laser element 11 is arranged so that its laser light emitting end face may become perpendicular to the bottom face of the package 14. Since the opening 14a of the package 14 is covered with a transparent substrate 15, the opening 104a is tightly closed. In addition, a mirror 21 is stuck to the main surface of the transparent substrate 15. Since the reflecting surface 25 of the mirror 21 is arranged to face the leaser light emitting end face of the semiconductor laser element 11, the surface 25 reflects the laser light 20 emitted from the semiconductor laser element 11 to the transparent substrate 15 side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical semiconductor device equipped with a semiconductor laser element serving as a light source of an optical recording device such as an optical disk or a magneto-optical disk.

  Optical semiconductor devices equipped with semiconductor laser elements are widely used as light sources for optical recording devices such as CDs (compact discs) and DVDs (digital versatile discs). An example of a conventional optical semiconductor device will be described below.

(First conventional example)
FIGS. 5A and 5B show the structure of an optical semiconductor device according to the first conventional example (see, for example, Patent Document 1). As shown in FIG. 5, a heat sink 103 having a height of 1.5 mm is fixed vertically to a base 104 having a disc shape made of a metal having a thickness of 1.0 mm. A submount 102 having a thickness of 250 μm and a length of 1.2 mm is interposed in the heat sink 103, and a semiconductor laser element 101 having a thickness of 100 μm and a length of 1.1 mm is held perpendicular to the base 104. .

  A cylindrical metallic cap 108 having a height of 1.8 mm and having a transparent window 105 made of glass is fixed to the base 104 by welding so as to cover the semiconductor laser element 101. Thereby, the semiconductor laser element 101 is sealed, and deterioration of the semiconductor laser element 101 due to moisture in the atmosphere is prevented.

  One of the n-side electrode and the p-side electrode of the semiconductor laser element 101 is electrically connected to the terminal 106A through the gold wire 113A and the heat sink 103 drawn from the surface of the submount 102, and the other electrode is The wire 113B is electrically connected to the terminal 106B.

  When a voltage is applied between the terminal 106A and the terminal 106B, a current flows through the semiconductor laser element 101, the semiconductor laser element 101 oscillates, and the laser beam 110 is emitted from the emission end face. The emitted laser beam 110 passes through the glass plate 105 and is extracted outside the optical semiconductor device. This laser beam can be used for optical systems of various optical recording apparatuses.

  FIG. 6 shows a schematic structure of an optical pickup which is one application example of an optical semiconductor device. As shown in FIG. 6, the laser light emitted from the optical semiconductor device 200 is divided into three beams by a grating element 201 that is a diffraction grating disposed in the optical path of the laser light. The split outgoing beam is collimated by the collimator lens 202 and then focused on the data recording layer provided on the surface of the optical disk 206 by the objective lens 205.

  The light beam is reflected on the data recording layer of the optical disc 206 and traces the incident path as a reflected beam. The reflected surface of the reflected beam is changed by a quarter-wave plate 204 provided in the optical path, and reflected by the deflecting beam splitter 203 to the light receiving element 209 side. The reflected laser light is collected by a collimator lens 207, divided into signals necessary for servo operation of the optical recording apparatus by a hologram element 208 that is a diffraction grating, and then received by a light receiving element 209.

(Second conventional example)
FIGS. 7A and 7B show the structure of an optical semiconductor device according to the second conventional technology (see, for example, Patent Document 2). As shown in FIG. 7, a resin package 304 in which an opening 304a is formed in a semiconductor laser element 301 having a thickness of 100 μm and a length of 1.1 mm with a submount 302 having a thickness of 250 μm interposed therebetween. It is fixed to the bottom of the.

  A mirror 211 made of silicon having a reflecting surface with an inclination angle of 45 ° is provided at a position facing the laser emission end surface of the semiconductor laser element 301 on the bottom surface of the package 304. A transparent window 305 is fixed so as to cover the opening 304a of the package 304, and the opening 304a is sealed.

In the optical semiconductor device of the second conventional example, the laser light 310 emitted from the semiconductor laser element 301 is reflected by the mirror 311 to the transparent window 305 side, passes through the transparent window 309, and is extracted outside the optical semiconductor device. .
JP-A-8-321657 (FIG. 4) JP-A-8-213641 (FIG. 7)

  However, in the optical semiconductor device according to the first conventional example, the semiconductor laser element 101 must be arranged so that the laser emission end face of the semiconductor laser element 101 is substantially parallel to the transparent window 105. For this reason, there is a problem that the thickness of the optical semiconductor device along the laser light emission direction is at least thicker than the length of the semiconductor laser element. Since the length of the semiconductor laser element is about 1 mm, the thickness along the emission direction of the optical semiconductor device including the stem and the cap is required to be about 3 mm, and the optical storage device or the like in which the optical semiconductor device is incorporated can be downsized. It becomes a big obstacle when becoming.

  Further, in order to prevent reliability degradation caused by the semiconductor laser element 101 absorbing moisture in the air, the semiconductor laser element 101 must be sealed in a package. In a conventional optical semiconductor device, It is necessary to use a metal package in terms of strength, and there is a problem that sealing is difficult.

  On the other hand, in the optical semiconductor device according to the second conventional example, the semiconductor laser element 301 can be arranged so that the laser emission end face of the semiconductor laser element 301 is perpendicular to the transparent window 305. However, when used as a light source for a DVD device or the like, the laser light extracted from the optical semiconductor device needs to have a spread angle of about ± 25 °. For this reason, when the semiconductor laser element is held on a submount having a thickness of 250 μm, it is necessary to use a large mirror having a thickness of at least about 500 μm.

  Usually, the mirror is formed by anisotropic etching of a silicon substrate. Therefore, since the etching rate is low, it is difficult to form a thick mirror, and there is a problem that the cost increases.

  Although it is conceivable to reduce the thickness of the mirror by reducing the thickness of the submount, if the thickness of the submount is reduced, it becomes difficult to handle the semiconductor laser device, and when it receives an impact Since the semiconductor laser element is easily broken, it is difficult to make the thickness of the submount thinner.

  Further, the thickness of the optical semiconductor device is limited by the thickness of the mirror, and there is a problem that the thickness of the optical semiconductor device cannot be sufficiently reduced.

  Furthermore, the conventional optical semiconductor device has a problem that many components are required when forming the optical pickup, and it is difficult to reduce the size of the optical pickup.

  The present invention solves the above-mentioned conventional problems, and can reduce the thickness along the laser beam emission direction without requiring a large mirror that reflects the laser beam, and forms an optical pickup. It is an object of the present invention to realize an optical semiconductor device that requires fewer parts.

  In order to achieve the above object, according to the present invention, an optical semiconductor device has a configuration in which laser light emitted from a semiconductor laser element is reflected by a mirror provided on a transparent substrate and emitted from the optical semiconductor device.

  Specifically, an optical semiconductor device of the present invention includes a semiconductor laser element, a transparent substrate that transmits laser light emitted from the semiconductor laser element, and a semiconductor laser element provided on the main surface of the transparent substrate on the semiconductor laser element side. And a mirror that reflects the laser beam emitted from the transparent substrate to the transparent substrate side.

  According to the optical semiconductor device of the present invention, the semiconductor laser includes the mirror provided on the main surface of the transparent substrate on the semiconductor laser element side and reflecting the laser beam emitted from the semiconductor laser element to the transparent substrate side. The semiconductor laser element can be arranged so that the emission end face for emitting the laser beam of the element is perpendicular to the transparent substrate. Therefore, even when a semiconductor laser element having a long length along the laser emission direction is used, the thickness of the optical semiconductor device itself can be reduced. Further, since the mirror is fixed to the transparent substrate, the positional relationship between the mirror and the semiconductor laser element can be freely arranged, so that a mirror having a small outer dimension can be used, and as a result, the optical semiconductor The cost required for the apparatus can be reduced.

  In the optical semiconductor device of the present invention, it is preferable that the semiconductor laser element is disposed so that the emission end face of the laser beam is perpendicular to the transparent substrate. By setting it as such a structure, a mirror can be reliably fixed to a transparent substrate.

  In the semiconductor device of the present invention, the mirror is preferably made of silicon and fixed to the transparent substrate with an adhesive interposed. With such a configuration, the mirror can be securely fixed to the transparent substrate.

  The optical semiconductor device of the present invention further includes a package in which an opening is formed, and the transparent substrate is disposed so that the main surface faces the opening and the opening is sealed, and the semiconductor laser element, the mirror, Is preferably housed inside an opening sealed by a transparent substrate. With such a configuration, the semiconductor laser element and the mirror can be easily sealed, and the semiconductor laser element can be reliably prevented from being deteriorated by moisture.

  In the optical semiconductor device of the present invention, it is preferable that a diffraction grating is formed on at least one of the main surface of the transparent substrate and the surface opposite to the main surface. With such a configuration, the number of components can be reduced when the optical semiconductor device is incorporated into the optical pickup. Moreover, since the mirror and the diffraction grating are integrated, the optical pickup can be easily adjusted.

  In the optical semiconductor device of the present invention, the semiconductor laser element is preferably fixed on the bottom surface of the package. Moreover, you may adhere on the side wall of a package. Furthermore, the semiconductor laser element may be fixed on the main surface of the transparent substrate. With such a configuration, the space of the optical semiconductor device can be used effectively, and the optical semiconductor device can be reliably downsized.

  The optical semiconductor device of the present invention further includes a light receiving element that converts the intensity of light into an electric signal, and the light receiving element preferably receives diffracted light obtained by diffracting incident light incident from the outside by a diffraction grating. By adopting such a configuration, it is not necessary to provide a light receiving element outside, so that the number of parts can be greatly reduced when the optical semiconductor device is incorporated into the optical pickup. In addition, since the optical pickup is integrally formed, the optical pickup can be easily adjusted.

  In this case, the semiconductor laser element is preferably fixed on the main surface of the transparent substrate, and the light receiving element is preferably fixed on the bottom surface of the package. With such a configuration, space can be used effectively and the optical semiconductor device can be reduced in size.

  According to the optical semiconductor device of the present invention, it is possible to reduce the thickness along the laser beam emission direction without requiring a large mirror for reflecting the laser beam, and when forming an optical pickup. An optical semiconductor device that requires fewer parts can be realized.

(First embodiment)
An optical semiconductor device according to a first embodiment of the present invention will be described with reference to the drawings. FIGS. 1A and 1B show the configuration of the optical semiconductor device of this embodiment. FIG. 1A shows a plan configuration when viewed from above, and FIG. 1B shows the Ib-Ib line in FIG. The cross-sectional structure in is shown.

  As shown in FIG. 1, a heat sink 13 is provided on the bottom surface of the resin package 14 in which the opening 14 a is formed, and an insulating submount 12 having an electrode formed on the surface of the heat sink 13. Is provided. The semiconductor laser element 11 is held on the submount 12 such that the end face of the laser beam is perpendicular to the bottom surface of the package 14, and the electrode formed on the submount 12 and the lower electrode of the semiconductor laser element 11. And are electrically connected.

  In the package 14, metal terminals 16A and terminals 16B are formed so as to penetrate the outer wall. The terminal 16A is electrically connected to an electrode provided on the lower side of the semiconductor laser element 11 through a wire 23A made of gold and an electrode formed on the submount 12. The terminal 16B is electrically connected to an electrode provided on the upper side of the semiconductor laser element 11 through a wire 23. Therefore, by applying a voltage between the terminal 16A and the terminal 16B, a current can be passed through the semiconductor laser element 11 to cause the semiconductor laser element 11 to emit light.

  A transparent substrate 15 made of glass having a thickness of, for example, 300 μm to 500 μm is disposed so as to cover the opening 14a of the package 14 with the main surface facing the opening 14a, and the opening 14a is sealed. Note that nitrogen gas is purged inside the sealed opening 14a. Further, a trapezoidal silicon mirror 21 is fixed to the main surface of the transparent substrate 15 facing the opening 14a. The mirror 21 is disposed so that the reflection surface 25 faces the laser emission end surface of the semiconductor laser element 11. The angle of the reflecting surface 25 with respect to the semiconductor laser element 11 is adjusted so that the laser beam 20 emitted from the semiconductor laser element 11 can be reflected toward the transparent substrate 15, and the laser beam 20 passes through the transparent substrate 15. The light is transmitted and emitted to the outside of the optical semiconductor device.

  The size of a normal semiconductor laser element used in a CD or DVD optical pickup is approximately 1 mm in length in the direction along the laser beam emission direction, but perpendicular to the laser beam emission direction. The height between the electrodes is only about 100 μm. For this reason, in the conventional optical semiconductor device in which the laser light emission end face is arranged in parallel with the transparent window for laser light emission, the thickness of the optical semiconductor device including the package is about 3 mm. In the optical semiconductor device of the embodiment, the thickness can be about 1.5 mm.

  In the optical semiconductor device of this embodiment, the mirror 21 that reflects the laser light is fixed to the transparent substrate 15. The mirror 21 is formed by anisotropically etching silicon from the viewpoint of cost. Therefore, it is difficult to form a thick mirror, and it is desirable to make the mirror 21 as small as possible.

  On the other hand, in an optical semiconductor device used for an optical pickup, it is necessary to emit a laser beam with a divergence angle of about ± 25 degrees. Therefore, the minimum necessary size of the mirror 21 is the mirror 21 and the semiconductor laser. It is determined by the positional relationship with the element 11. In this case, when the mirror 21 is arranged so that the horizontal position of the mirror 21 is as close to the semiconductor laser element 11 as possible and the vertical position of the mirror 21 is at the same level as the semiconductor laser element 11, the size of the mirror 21 is reduced. It can be minimized.

  For example, when the thickness of the semiconductor laser element 11 is 100 μm and the thickness of the submount is 250 μm, a mirror 21 having a reflection surface tilt of 45 ° is provided on the bottom surface of the package 14 and spreads by ± 25 °. In order to secure the corner, the mirror 21 needs to have a thickness of 470 μm or more. Although it is possible to reduce the size of the mirror by providing a level alignment mount below the mirror 21, in this case, the number of parts increases.

  On the other hand, when the mirror 21 is provided on the transparent substrate 15, the lower part of the mirror 21 is not necessary. In addition, since the distance between the mirror 21 and the semiconductor laser element 111 can be shortened as compared with the case where the mirror 21 is provided on the bottom surface of the package 14, if the thickness of the mirror 21 is 210 μm or more, the spread angle is ± 25 °. It can be secured. Accordingly, the time and cost required for forming the mirror can be greatly reduced. As a result, the thickness of the optical semiconductor device can be reduced.

  Further, in the optical semiconductor device of this embodiment, since the semiconductor laser element 11 is arranged in parallel with the bottom surface of the package 14, the package 14 does not need a large strength, and a resin package can be used. Therefore, the transparent substrate 15 serving as the laser light emission window can be easily bonded to the package 14 using an ultraviolet curable adhesive or the like. Therefore, the process of sealing the semiconductor laser element 11 by sealing the opening 14a of the package 14 can be simplified. Further, by making the package 14 made of resin, it becomes easy to insulate the wiring and terminals connected to the semiconductor laser element 11.

  Hereinafter, an example of a method for manufacturing the optical semiconductor device of this embodiment will be described. An electrode formed on the upper surface of the submount 12 made of insulating aluminum nitride (AlN) having a thickness of 250 μm and electrodes formed on both surfaces is connected to one electrode surface of the semiconductor laser element 11 by a gold-tin eutectic crystal. To join. At this time, the semiconductor laser element 11 is fixed so that the laser emission position side of the semiconductor laser element 11 is on the submount 12 side.

  Next, the submount 12 to which the semiconductor laser element 11 is bonded is fixed to the heat sink 13 formed on the bottom surface of the resin package 14 by using, for example, a heat conductive paste adhesive containing silver. . Subsequently, the electrode formed on the upper surface of the submount 12 and the terminal 16A formed on the package 14 are electrically connected using a wire 23A made of gold. Further, the upper electrode of the semiconductor laser element 11 and the terminal 16B are electrically connected using a wire 23B made of gold.

  Next, an adhesive layer 24 made of an organic resin such as benzocyclobutene is formed at a predetermined position on one surface of the transparent substrate 15. The mirror 21 is pressure-bonded to the position where the adhesive layer 24 is formed, and further bonded by heating. The mirror 21 is formed by etching a substrate made of silicon using a potassium hydroxide or tetramethylammonium hydroxide solution.

  Next, an ultraviolet curable adhesive is applied to the upper surface of the resin package 14 on which the semiconductor laser element 11 is mounted, and then the surface of the transparent substrate 15 on which the mirror 21 is provided faces the package 14. The transparent substrate 15 and the package 14 are brought into close contact with each other. Subsequently, after adjusting the positional relationship between the mirror 21 and the semiconductor laser element 11, the adhesive is cured by irradiating ultraviolet rays from above the transparent substrate 15, and the opening 14 a of the package 14 is sealed. By performing this step in a nitrogen atmosphere, the semiconductor laser element 11 can be sealed with nitrogen.

  In this embodiment, the mirror formed by anisotropic etching of the silicon substrate is used, but a mirror formed by polishing glass may be used. Further, although glass is used for the transparent substrate, a resin material or the like that is transparent to sapphire or laser light may be used.

  In the present embodiment, the submount and the heat sink are bonded with a heat conductive paste adhesive, but may be bonded using a solder material such as gold-tin eutectic.

  Although the semiconductor laser element is disposed so that the emission end face is perpendicular to the bottom surface of the package, the emission angle of the laser beam from the optical semiconductor device can be adjusted by shifting the angle. The semiconductor laser element may be fixed on the side wall instead of on the bottom surface of the package.

(Second Embodiment)
An optical semiconductor device according to the second embodiment of the present invention will be described below with reference to the drawings. 2A and 2B show the configuration of the optical semiconductor device of the present embodiment. FIG. 2A shows a plan configuration when viewed from above, and FIG. 2B shows the IIb-IIb line in FIG. The cross-sectional structure in is shown. In FIG. 2, the same components as those in FIG.

  As shown in FIG. 2, in the optical semiconductor device of this embodiment, the heat sink 13, the terminal 16A, and the terminal 16B are formed on the same surface as the surface on which the mirror 21 of the transparent substrate 15 is provided. A semiconductor laser element 11 is fixed to the heat sink 13 with a submount 12 interposed. One electrode of the semiconductor laser element 11 is electrically connected to the terminal 16 </ b> A via an electrode formed on the submount 12 and a wire 23 </ b> A connected to the electrode of the submount 12. The other electrode of the semiconductor laser element 11 is electrically connected to the terminal 16B through a wire 23B.

  A diffraction grating 35 is formed on the surface of the transparent substrate 15 opposite to the surface on which the mirror 21 is provided. The diffraction grating 35 functions as a grating element, and separates the laser light 20 emitted from the optical semiconductor device into three light components of 0th order light, + 1st order light, and −1st order light. Therefore, it is not necessary to separately provide a grating element when forming an optical pickup using an optical semiconductor device, and the optical pickup can be reduced in size.

  Further, since the position of the diffraction grating 35 is fixed with respect to the mirror 21 and the semiconductor laser element 11, it is not necessary to adjust the position of the grating element when forming the optical pickup, and the manufacturing process of the optical pickup is simplified. It becomes possible to do.

  Further, in the optical semiconductor device of this embodiment, the semiconductor laser element 11 is provided on the transparent substrate 15. For this reason, alignment of the semiconductor laser element 11 and the mirror 21 becomes easy.

  Below, an example of the manufacturing method of the optical semiconductor device of this embodiment is demonstrated. First, the diffraction grating 35 is formed by etching the surface of the glass substrate to which the mirror 21 is fixed with hydrofluoric acid or the like. Next, the heat sink 13, the terminal 16 </ b> A, and the terminal 16 </ b> B are bonded to the surface of the glass substrate on which the diffraction grating 35 is formed, on the side opposite to the diffraction grating 35. Subsequently, the semiconductor laser element 11 fixed to the submount 12 in advance is mounted on the heat sink 13, and the semiconductor laser element 11 and the terminals 16A and 16B are electrically connected by the wires 23A and 23B.

  Next, the mirror 21 is bonded to a predetermined position of the transparent substrate 15 as in the first embodiment. Subsequently, the transparent substrate 15 and the package 14 are bonded and fixed with an ultraviolet curable adhesive.

  In the optical semiconductor device of the present embodiment, the diffraction grating 35 is provided on the surface of the transparent substrate 15 opposite to the surface on which the mirror 21 is provided, but may be provided on the same surface as the mirror 21. . Further, the semiconductor laser element 11 may be provided on the bottom surface of the package 14 as in the first embodiment.

(Third embodiment)
An optical semiconductor device according to the third embodiment of the present invention will be described below with reference to the drawings. 3A and 3B show the configuration of the optical semiconductor device of the present embodiment. FIG. 3A shows a plan configuration when viewed from above, and FIG. 3B shows the IIIb-IIIb line in FIG. The cross-sectional structure in is shown. In FIG. 3, the same components as those in FIG.

  As shown in FIG. 3, in the optical semiconductor device of this embodiment, a light receiving element 41 for converting the intensity of laser light incident on the element into an electrical signal is provided on the bottom surface of the package 14 with a light receiving element mounting portion 48 interposed therebetween. It has been. A plurality of metal terminals 49 are formed in the package 14 so as to penetrate the side wall, and the terminals 49 and the light receiving element 41 are electrically connected through wires 50. The light receiving element 41 is provided with a plurality of light receiving portions, and the intensity of the light incident on each light receiving portion 42 is subjected to signal processing in a circuit provided in the light receiving element 41 and then applied to the terminal 49 as an electrical signal. Is output.

  In the transparent substrate 15 of the present embodiment, a first diffraction grating 45A having a grating function is formed on the surface where the mirror 21 is provided, and a second diffraction grating 45B having a hologram function is formed on the opposite surface. Is formed. The laser light incident on the second diffraction grating 45B of the transparent substrate 15 from the outside of the optical semiconductor device is divided into two light beams of + 1st order light and −1st order light by the second diffraction grating 45B and It enters each light receiving part 42.

  Since the optical semiconductor device of the present embodiment includes a diffraction grating and a light receiving element in the device, an optical pickup can be formed simply by providing a collimator lens and an objective lens outside. 4A and 4B show an example of the configuration of an optical pickup using the optical semiconductor device of the present embodiment, and FIG. 4A shows a cross-sectional state taken along line IIIb-IIIb in FIG. b) shows a cross-sectional state in a direction perpendicular to the line IIIb-IIIb.

  As shown in FIGS. 4A and 4B, the laser light 20 emitted from the semiconductor laser element 11 of the optical semiconductor device is reflected by the mirror 21 toward the transparent substrate 15. The reflected laser beam 20 is divided into a plurality of light beams by the first diffraction grating 45A formed on the transparent substrate 15 and having a grating function, and is emitted from the optical semiconductor device.

  Each light beam emitted from the optical semiconductor device is collimated by the collimator lens 52 and then collected by the objective lens 55 in a storage area formed on the optical disk 56. The reflected light reflected from the optical disk 56 follows a path opposite to the incident path and returns to the optical semiconductor device. Since the transparent substrate 15 of the optical semiconductor device is provided with the second diffraction grating 45B having a hologram function, the reflected light is divided into a plurality of light beams and is incident on the light receiving unit 42 provided in the light receiving element 41. Each is guided. As a result, the contents stored in the optical disk can be read out, and the servo circuit 59 for driving the servo mechanism 58 for finely adjusting the distance between the optical disk and the objective lens and focusing on the storage area of the optical disk is necessary. Servo signals can be generated.

  With such a configuration, the number of parts of the optical pickup can be greatly reduced. Further, since the semiconductor laser element, the mirror, the diffraction grating, and the light receiving element are integrally formed, an optical pickup having few adjustment points can be realized.

  In the optical semiconductor device of this embodiment, the diffraction grating is formed on both surfaces of the transparent substrate. However, the diffraction grating may be formed only on one surface of the transparent substrate according to the configuration of the optical pickup to be incorporated.

  The optical semiconductor device of the present invention can reduce the thickness along the laser beam emission direction without requiring a large mirror for reflecting the laser beam, and the number of components when forming the optical pickup. Therefore, it is useful as an optical semiconductor device equipped with a semiconductor laser element serving as a light source of an optical recording device such as an optical disk or a magneto-optical disk.

(A) And (b) shows the structure of the optical semiconductor device which concerns on the 1st Embodiment of this invention, (a) is the top view seen from the top, (b) is Ib- of (a). It is sectional drawing in the Ib line. (A) And (b) shows the structure of the optical semiconductor device which concerns on the 2nd Embodiment of this invention, (a) is the plane | planar block diagram seen from the top, (b) is (a). It is sectional drawing in the IIb-IIb line. (A) And (b) shows the structure of the optical semiconductor device which concerns on the 3rd Embodiment of this invention, (a) is the top view seen from the top, (b) is IIIb- of (a). It is sectional drawing in the IIIb line. (A) And (b) is a figure which shows an example of a structure of the optical pick-up using the optical semiconductor device which concerns on the 3rd Embodiment of this invention. (A) And (b) shows the structure of the optical semiconductor device which concerns on a 1st prior art example, (a) is the top view seen from the top, (b) is in the Vb-Vb line | wire of (a). It is sectional drawing. It is a block diagram which shows the structure of the optical pick-up concerning a 1st prior art example. (A) And (b) shows the structure of the optical semiconductor device which concerns on a 2nd prior art example, (a) is the top view seen from the top, (b) is in the VIIb-VIIb line | wire of (a). It is sectional drawing.

Explanation of symbols

11 Semiconductor laser element 12 Submount 13 Heat sink 14 Package 14a Opening 15 Transparent substrate 16A Terminal 16B Terminal 20 Laser light 21 Mirror 23A Wire 23B Wire 24 Adhesive layer 25 Reflecting surface 35 Diffraction grating 41 Light receiving element 42 Light receiving part 45A First diffraction Grating 45B Second diffraction grating 48 Light receiving element mounting portion 49 Terminal 52 Collimator lens 55 Objective lens 56 Optical disk 58 Servo mechanism 59 Servo circuit

Claims (10)

A semiconductor laser element;
A transparent substrate that transmits the laser light emitted from the semiconductor laser element;
An optical semiconductor device comprising: a mirror provided on a main surface of the transparent substrate on the semiconductor laser element side and reflecting a laser beam emitted from the semiconductor laser element to the transparent substrate side.   2. The optical semiconductor device according to claim 1, wherein the semiconductor laser element is arranged so that an emission end face of a laser beam is perpendicular to the transparent substrate.   3. The optical semiconductor device according to claim 1, wherein the mirror is made of silicon and is fixed to the transparent substrate with an adhesive interposed therebetween. A package having an opening formed therein;
The transparent substrate is disposed so that the main surface faces the opening and the opening is sealed.
4. The optical semiconductor device according to claim 1, wherein the semiconductor laser element and the mirror are housed inside the opening sealed by the transparent substrate. 5.   The optical semiconductor device according to claim 4, wherein a diffraction grating is formed on at least one of the main surface of the transparent substrate and a surface opposite to the main surface.   The optical semiconductor device according to claim 4, wherein the semiconductor laser element is fixed on a bottom surface of the package.   6. The optical semiconductor device according to claim 4, wherein the semiconductor laser element is fixed on a side wall of the package.   The optical semiconductor device according to claim 4, wherein the semiconductor laser element is fixed on the main surface of the transparent substrate. A light receiving element that converts light intensity into an electrical signal;
6. The optical semiconductor device according to claim 5, wherein the light receiving element receives diffracted light obtained by diffracting incident light incident from outside by the diffraction grating. The semiconductor laser element is fixed on the main surface of the transparent substrate,
The optical semiconductor device according to claim 9, wherein the light receiving element is fixed on a bottom surface of the package.