JPH05129711A - Package type semiconductor laser device - Google Patents

Abstract

PURPOSE:To reduce the height and size of the part of a semiconductor laser chip in the so-called package type semiconductor laser device which is packaged by a cap body, and to cut down the cost of manufacture. CONSTITUTION:A laser chip 15 is installed sideways on the upper surface of a heat dissipating plate 11 made of a thin metal plate in such a manner that a laser beam will be emitted in the direction almost in parallel with the upper surface of the heat dissipating plate 11. A cap body 12, provided with a transparent window, is installed on the part opposing to the upper surface of the heat dissipating plate 11 covering the semiconductor laser chip 15. Besides, a reflecting part 21 used to change the direction of the laser beam emitted from the semiconductor laser chip 15 toward the transparent window, is provided inside the cap body 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a semiconductor laser device in which a semiconductor laser chip is used as a light emitting element of a laser beam and a portion of the semiconductor laser chip is packaged with a cap body.

[0002]

2. Description of the Related Art Conventionally, a package type semiconductor laser device of this type is described in, for example, JP-A-62-219672 or JP-A-62-58066, and
As shown in FIGS. 16 to 18, the heat sink body 2 is integrally formed on the upper surface of the stem 1 that also serves as a heat dissipation plate and is formed of a metal such as carbon steel into a disk shape having a diameter D and a thickness T. Then, the semiconductor laser chip 3 is mounted on the side surface of the heat sink body 2 through the submount 4, while the cap body 5 having the transparent window 6 such as glass is provided on the upper surface of the stem 1 and the heat sink body. The semiconductor laser chip 3 and the submount 4 are packaged by mounting the semiconductor laser chip 3 and the submount 4.

However, reference numeral 9 is a monitoring photodiode provided in the recess 9a on the upper surface of the stem 1, reference numeral 7a is a first lead terminal fixed to the lower surface of the stem 1, and reference numerals 7b and 7c are the above-mentioned. The second and third lead terminals inserted through the through holes 1a and 1b formed in the stem 1 are shown respectively, and the second and third lead terminals 7b and 7c are shown.
Is fixed in the through holes 1a and 1b through an insulating seal material 8, and further between the semiconductor laser chip 3 and the submount 4, between the second lead terminal 7b and the submount 4, and The third lead terminal 7c and the monitoring photodiode 9 are connected to each other by thin metal wires A, B and C in the cap body 5.

[0004]

However, in this conventional package type semiconductor laser device, the laser beam emitted from the semiconductor laser chip 3 is applied to the block body 2 protruding from the stem 1 of the semiconductor laser chip 3. The stem 1 is mounted so that the axis of E is upward from the upper surface of the stem 1.

Therefore, in the package type semiconductor laser device, the height dimension H of the laser beam E along the axis is at least a value obtained by adding the height dimension of the heat sink 2 to the thickness T of the stem 1. In addition to this, the thickness T of the stem 1 cannot be made thin because the heat sink 2 is integrally formed on the stem 1, and the height dimension H becomes considerably high. However, there was a problem that it could not be thin.

Moreover, in the conventional package type semiconductor laser device, the heat sink 2 for mounting the semiconductor laser chip 3 is integrally formed on the upper surface of the stem 1, and the heat sink 2 is attached to the stem 1. There is also a problem that the manufacturing cost is significantly increased because a large number of processing steps are required to integrally mold the.

It is a technical object of the present invention to provide a package type semiconductor laser device which solves these problems.

[0008]

In order to achieve this technical object, the present invention provides a semiconductor laser chip on the upper surface of a heat dissipation plate made of a thin metal plate and a laser beam from the semiconductor laser chip on the heat dissipation plate. The device is mounted sideways so as to fire in a direction substantially parallel to the upper surface, and a cap body provided with a transparent window in a portion facing the upper surface of the heat dissipation plate is mounted so as to cover the semiconductor laser chip. A reflecting portion for changing the direction of the laser beam emitted from the semiconductor laser chip toward the transparent window is provided inside the cap body.

[0009]

Thus, the upper surface of the heat dissipation plate is
The semiconductor laser chip is mounted sideways, and the laser beam from the semiconductor laser chip is configured to be redirected by the reflecting portion toward the transparent window in the cap body to cover the laser beam so that the laser beam is directed to the upper surface of the heat sink. Since the heat sink which is required in the conventional package type semiconductor laser device can be omitted, the height dimension along the axis of the laser beam can be reduced. At the same time, the number of steps required to process the heat sink can be greatly reduced.

Therefore, according to the present invention, the package type semiconductor laser device can be made thin and the manufacturing cost thereof can be greatly reduced. By the way, in this type of semiconductor laser device, a laser beam emitted from the semiconductor laser chip is monitored by a photodiode, and the current applied to the semiconductor laser chip is increased or decreased in accordance with this, whereby the laser beam The intensity is controlled to be substantially constant, and when the laser beam emitted from the semiconductor laser chip is monitored by a photodiode, in order to reflect the laser beam emitted from the semiconductor laser chip. As described in "Claim 2", as the reflecting portion of the above, by using a monitor photodiode having a reflecting film on the surface through which a part of the laser beam is transmitted, the laser beam emitted from the semiconductor laser chip is used. ,
Since it can be directly monitored by the photo diode, the output of the monitor can be increased and the control accuracy of the laser beam monitor can be improved. Therefore, the number of parts can be reduced and the cost can be reduced.

Further, the mounting portion for the reflecting portion is provided on the heat sink side as described in "Claim 3".
Since the semiconductor laser chip and the reflecting portion for the semiconductor laser chip can be attached to one heat radiating plate instead of separate parts, the accuracy of the size and angle between the semiconductor laser chip and the reflecting portion for the semiconductor laser chip That is, the accuracy of the emission angle and the emission position of the laser beam can be significantly improved as compared with the case where the mounting portion for the reflecting portion is provided on the side of the cap body. It is sufficient to mount the cap body after mounting the parts, and the assembling process becomes simpler than the case where the mounting part for the reflecting portion is provided on the cap body side, so that the manufacturing cost can be reduced.

On the other hand, the semiconductor laser device requires a plurality of lead terminals for applying a current to the semiconductor laser chip, and each of the lead terminals is described in "Claim 4". As described above, since the lead terminals are formed on the heat sink as the wiring pattern of the conductive film, the lead terminals can be formed more easily than the case where the lead terminals are formed on the cap body side, and thus the manufacturing cost is reduced. It can be reduced.

Furthermore, by integrally forming the cap body with a synthetic resin having a light-transmitting property as described in "Claim 5," the number of parts is reduced and the manufacturing process is reduced. Since it is simple, the manufacturing cost can be greatly reduced.

[0014]

Embodiments of the present invention will now be described with reference to the drawings. 1 to 4 show a first embodiment, in which reference numeral 10 indicates a package type semiconductor laser device according to the present invention.
Reference numeral 0 denotes a heat dissipation plate 11 and a cap body 12 having a transparent window made of glass or the like in a portion facing the heat dissipation plate 11.

The heat radiating plate 11 is composed of a carbon steel plate, a copper plate, or an aluminum plate, the surface of which is plated with a metal such as Au. The submount 13 is fixed, and the semiconductor laser chip 15 is emitted onto the upper surface of the submount 13, and the laser beam from the front cleavage plane 15a of the semiconductor laser chip 15 is emitted in a direction substantially parallel to the upper surface of the heat dissipation plate 11. So that it sticks sideways.

On the other hand, the cap body 12 having the transparent window
Is a frame-shaped body 16 made of a heat-resistant insulator such as ceramic, and an adhesive or a metal solder 1 for glass on the upper surface of the frame-shaped body 16.
The glass plate 17 joined at 8 is mounted on the upper surface of the heat dissipation plate 11 so as to be fitted to the semiconductor laser chip 15 and the submount 13, and then the heat dissipation is performed. It is fixed to the plate 11 with an adhesive or low-temperature metal solder 19.

The frame type main body 1 of the cap body 12
A mounting portion 20 for a reflecting portion is provided on a portion of the inner surface of the semiconductor laser chip 6 facing the semiconductor laser chip 15, and a laser beam emitted from the front cleavage surface 15 a of the semiconductor laser chip 15 is mounted on the mounting portion 20. The reflection part 21 is fixed so as to change the direction of E toward the glass plate 17 of the cap body 12.

In the case of the first embodiment, the heat sink 1
1 itself also serves as a first lead terminal for the semiconductor laser chip 15, and the second and third lead terminals 22, 23 for the semiconductor laser chip 15 and the monitor photodiode 14, respectively, are It is formed inside the frame main body 16 of the cap body 12. Furthermore, as shown in FIG. 3, between the rear cleavage surface 15b of the semiconductor laser chip 15 and the monitoring photodiode 14 on the upper surface of the submount 13, a monitor surface emitted from the rear cleavage surface 15b is used. A transparent or semitransparent synthetic resin waveguide 24 for guiding the laser beam to the monitoring photodiode 14 is applied.

According to this structure, although the semiconductor laser chip 15 is mounted laterally on the upper surface of the heat dissipation plate 11, the semiconductor laser chip 1 is oriented horizontally.
The laser beam E from the front cleavage plane 15a in FIG. 5 can be emitted in the upward direction from the upper surface of the heat dissipation plate 11 through the glass plate 17 of the cap body 12 by the direction change by the reflection section 21.

Therefore, since it is not necessary to mount the semiconductor laser chip 15 in the vertical direction on the upper surface of the heat dissipation plate 11, in the conventional package type semiconductor laser device, the semiconductor laser chip is mounted in the vertical direction. The heat sink, which was necessary for this, can be eliminated. FIG. 5 and FIG. 6 show a second embodiment. In the second embodiment, the rear cleavage surface 15b of the semiconductor laser chip 15 mounted sideways on the upper surface of the heat dissipation plate 11 via the submount 13 is shown. The laser beam is completely blocked by the reflection film 25 so that all of the laser beam is
On the other hand, a monitor photodiode 26 is attached to the reflection portion attachment portion 20 in the frame body 16 of the cap body 12, and the semiconductor laser chip is mounted on the surface of the photodiode 26. Most of the laser beam (about 80%) emitted from the front cleavage plane 15a of 15 is redirected toward the glass plate 17 of the cap 12 and the remaining laser beam is transmitted to the photodiode 26. The film 21a is provided.

In the second embodiment, the frame-shaped body 16 of the cap body 12 is made of liquid crystal polymer, and the reference numeral 22a in the figure indicates a second lead terminal for the semiconductor laser chip 15. , 23a and 23b respectively indicate lead terminals for the monitoring photodiode 26, and these lead terminals 22a, 23a and 23b are formed on the surface of the liquid crystal polymer frame body 16 of the cap body 12. ..

According to the second embodiment, since the laser beam E emitted from the front cleavage plane 15a of the semiconductor laser chip 15 can be directly monitored by the photodiode 26, the monitor output is increased. In addition to that, there is an advantage that the control accuracy by monitoring the laser beam can be improved. Next, FIGS. 7 and 8 show a third embodiment. In the third embodiment, a flat U-shaped cut line 27 is engraved on a heat dissipation plate 11 made of a thin metal plate,
By bending the inner part upward,
A mounting portion 20a for mounting the reflecting portion 21 is formed.

As mentioned above, when the plane U-shaped cut line 27 is engraved and the inner portion thereof is bent upward to form the mounting portion 20a for the reflecting portion, the cut line is formed. A through hole 27a is formed in the portion 27, and the through hole 27a is formed by the synthetic resin 2
Fill with 8 to close. In addition, in the third embodiment, instead of providing the mounting portion 20 for mounting the reflecting portion on the side of the cap body 12 as in the above-described respective embodiments, the mounting portion 20a for mounting the reflecting portion on the side of the heat dissipation plate 11 is provided. Is provided,
As a result, the semiconductor laser chip 15 and the reflecting portion 21 for the semiconductor laser chip 15 are not separated into separate parts, but one heat dissipation plate 1
Since it can be attached to the semiconductor laser chip 15, the accuracy of the size and angle between the semiconductor laser chip 15 and the reflector 21 with respect to the semiconductor laser chip 15, that is, the accuracy of the emission angle and the emission position of the laser beam D is determined by the reflection portion. Since the mounting portion 20 for use on the cap body 12 can be greatly improved, the cap body 12 can be mounted after the semiconductor laser chip 15 and the reflection portion 21 are mounted on the heat dissipation plate 11. It is good, and the assembling process is the same as the reflection part 2 described above.
Since it is simpler than the case of mounting 1 on the cap body 12 side, there is an advantage that the manufacturing cost can be reduced as compared with the case of the first to third embodiments.

When the mounting portion for the reflecting portion is provided on the heat sink 11 side as described above, the heat sink 11 is partially deformed by deformation as in the fourth embodiment shown in FIGS. 9 and 10. The reflecting portion mounting portion 21b may be configured as described above. By doing so, it is necessary to close the through hole 27a with a synthetic resin as in the third embodiment. I don't. However, when the mounting portion 20a for the reflecting portion having the configuration as in the third embodiment is configured,
The tilt angle of the reflection part 21 can be finely adjusted.

Furthermore, FIGS. 11 to 13 show a fifth embodiment. In the fifth embodiment, an insulating film 29 is formed on the upper surface of the heat dissipation plate 11, and the surface of the insulating film 29 is A first lead terminal 30 for the semiconductor laser chip 15 and second and third lead terminals 22 on the upper surface of the submount 13.
b and 23c are formed as a wiring pattern of a conductor film, and the lead terminals 30 and 22 are thus formed.
These lead terminals can be formed by forming b and 23c as a wiring pattern of a conductor film on the heat sink 11, and each lead terminal can be formed in the frame of the cap body 12 as in the above-described embodiments. This can be done more easily than in the case of forming it on the mold body 16 side, so that the manufacturing cost is
~ It can be reduced compared to the case of the fourth embodiment.

In the fifth embodiment, the submount 13 with the semiconductor laser chip 15 is directly mounted on the heat sink 11 without an insulating film, while the second and third submounts are mounted. By forming only the lead terminals 22b and 23c on the surface of the heat dissipation plate 11 with an insulating film interposed, the first lead terminal 30 may also be used as the heat dissipation plate 11.

Further, as shown in FIG. 14, the heat dissipation plate 11 is provided with an extension portion 11a from the cap body 12, and the attachment hole 3 of the semiconductor laser device 10 is attached to the extension portion 11a.
It is also possible to construct so that 1 is provided. Furthermore, in each of the above embodiments, the cap body 12 is replaced by
And the glass plate 17 bonded to the upper surface of the glass plate 17 with the adhesive or the metal solder 18 for glass is shown. However, the present invention is not limited to this, and as shown in FIG. The cap body 12a may be integrally formed of the synthetic resin or the like. By doing so, the number of parts is reduced and the manufacturing process is simplified, so that the manufacturing cost is significantly reduced. You can do it.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a semiconductor laser device according to a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is an enlarged view of a main part of FIG.

FIG. 4 is a perspective view of the semiconductor laser device according to the first embodiment in a disassembled state.

FIG. 5 is a vertical sectional front view of a semiconductor laser device according to a second embodiment of the present invention.

FIG. 6 is a perspective view of a semiconductor laser device according to a second embodiment.

FIG. 7 is a vertical sectional front view of a semiconductor laser device according to a third embodiment of the present invention.

FIG. 8 is a perspective view of a heat dissipation plate in the semiconductor laser device of the third embodiment.

FIG. 9 is a vertical sectional front view of a semiconductor laser device according to a fourth embodiment of the present invention.

10 is a sectional view taken along line XX of FIG.

FIG. 11 is a vertical sectional front view of a semiconductor laser device according to a fifth embodiment of the present invention.

12 is a plan sectional view taken along the line XII-XII of FIG.

FIG. 13 is a perspective view of a heat dissipation plate in the semiconductor laser device of the fifth embodiment.

FIG. 14 is a perspective view showing another embodiment of the present invention.

FIG. 15 is a perspective view showing a further embodiment of the present invention in an exploded state.

FIG. 16 is a vertical sectional front view of a conventional semiconductor laser device.

17 is a sectional view taken along line XVII-XVII of FIG.

18 is a sectional view taken along line XVIII-XVIII of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 semiconductor laser device 11 heat sink 12, 12a cap body 13 submount 15 semiconductor laser chip 16 frame main body 17 glass plate 20, 20a, 20b reflection part mounting part 21, 21a reflection part 22, 23, 22a, 23a, 23b , 22b, 23
c, 30 Lead terminal 26 Photo diode for monitor

Claims (5)

[Claims] 1. A semiconductor laser chip is mounted on an upper surface of a heat dissipation plate made of a thin metal plate sideways so as to emit a laser beam from the semiconductor laser chip in a direction substantially parallel to the upper surface of the heat dissipation plate. A cap body having a transparent window in a portion facing the upper surface of the heat dissipation plate is attached so as to cover the semiconductor laser chip, and a laser beam emitted from the semiconductor laser chip is further provided inside the cap body. A semiconductor laser device of package type, characterized in that a reflection portion is provided for changing the direction of the light toward the transparent window. 2. A semiconductor laser chip is mounted on the upper surface of a heat dissipation plate made of a thin metal plate sideways so as to emit a laser beam from the semiconductor laser chip in a direction substantially parallel to the upper surface of the heat dissipation plate. A cap body having a transparent window in a portion facing the upper surface of the heat dissipation plate is attached so as to cover the semiconductor laser chip, and a laser beam emitted from the semiconductor laser chip is further provided inside the cap body. Is provided with a reflecting portion for changing the direction toward the transparent window, and the reflecting portion is composed of a monitor photodiode having a reflecting film on the surface through which a part of the laser beam is transmitted. Package type semiconductor laser device. 3. A semiconductor laser chip is mounted laterally on the upper surface of a heat dissipation plate made of a thin metal plate so as to emit a laser beam from the semiconductor laser chip in a direction substantially parallel to the upper surface of the heat dissipation plate. A cap body having a transparent window in a portion facing the upper surface of the heat dissipation plate is attached so as to cover the semiconductor laser chip, and a laser beam emitted from the semiconductor laser chip is further provided inside the cap body. A package-type semiconductor laser device, characterized in that while a reflection part for changing the direction toward the transparent window is provided, a mounting part for the reflection part is provided on the heat dissipation plate side. 4. A semiconductor laser chip is mounted laterally on an upper surface of a heat dissipation plate made of a thin metal plate so as to emit a laser beam from the semiconductor laser chip in a direction substantially parallel to the upper surface of the heat dissipation plate. A cap body having a transparent window in a portion facing the upper surface of the heat dissipation plate is attached so as to cover the semiconductor laser chip, and a laser beam emitted from the semiconductor laser chip is further provided inside the cap body. A package-type semiconductor, characterized in that while providing a reflection part for changing the direction toward the transparent window, various lead terminals for the semiconductor chip are formed as a wiring pattern of a conductor film on the surface of the heat dissipation plate. Laser device. 5. A semiconductor laser chip is mounted on a top surface of a heat dissipation plate made of a thin metal plate sideways so as to emit a laser beam from the semiconductor laser chip in a direction substantially parallel to the top surface of the heat dissipation plate. A cap body having a transparent window in a portion facing the upper surface of the heat dissipation plate is attached so as to cover the semiconductor laser chip, and a laser beam emitted from the semiconductor laser chip is further provided inside the cap body. A package-type semiconductor laser device, characterized in that the cap body is integrally formed of a translucent synthetic resin or the like while a reflecting portion is provided for changing the direction toward the transparent window.