JP2005012242A - Semiconductor laser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor laser which is manufactured at a low cost and miniaturized. <P>SOLUTION: A LD 1 is mounted on a metal frame 41 via a submount 2, and the LD 1 and the surface of the submount 2 are covered with transparent molded resin 9 so that laser beam 8 is launched in the direction parallel to the main surface of the metal frame 41. Furthermore, only a region 10 in the molded resin 9, through which the laser beam passes, is made to be a surface perpendicular to the metal frame 41 so that a draft angle of a mold to the molded resin is made to be zero, and the other regions in side surfaces 91, 92 of the molded resin 9 incline with respect to the metal frame 41. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor laser device, and more particularly to a semiconductor laser device in which a laser diode disposed on a metal frame is sealed with a mold resin.

  FIG. 2 is a cross-sectional view showing the structure of a conventional semiconductor laser device. In FIG. 2, reference numeral 1 denotes a laser diode (hereinafter referred to as LD), and 3 denotes heat for efficiently dissipating heat generated during operation of the LD 1 to the outside. The thickness of the metal block in the direction perpendicular to the surface on which the LD 1 is placed is about 1400 μm. Reference numeral 2 denotes a submount made of Si or the like for relieving stress applied to the LD 1 due to thermal expansion and contraction of the metal block 3, and the thickness thereof does not deteriorate the thermal radiation, for example, 150 to 250 μm. Yes. 4 is a bottom member of the package, 5 is a wire, 6 is a metal cap, 6a is an opening provided at the bottom of the metal cap 6, 7 is a window made of a material transparent to laser light such as glass, and 8 is A laser beam 20 emitted from the LD 1 is a metal lead. This semiconductor laser device is a so-called can type in which the LD 1 and the like are sealed with a metal cap 6. In this semiconductor laser device, when a current is passed through the LD 1 through the leads 20, the laser beam 8 is emitted. The laser beam 8 is emitted from the emission end face of the LD 1, passes through the window portion 7, and is emitted from the semiconductor laser device.

  Next, the manufacturing method will be described. First, the LD 1 is die-bonded to the metal block 3 through the submount 2. Subsequently, the metal block 3 is mounted on the main surface of the bottom member 4 of the package so that the laser beam 8 is emitted vertically. Thereafter, the LD 1 is electrically connected to the metal lead 20 by the wire 5.

  Subsequently, the window 7 is bonded to the bottom of the metal cap 6 so as to close the opening 6 a of the metal cap 6, and the metal cap 6 is attached to the package bottom member 4 in order to protect the LD 1 from the outside environment. The main surface is welded so as to cover the LD 1, the submount 2, and the metal block 3 to obtain the semiconductor laser device shown in FIG.

  As described above, the conventional can-type semiconductor laser device is configured to extract the laser beam 8 perpendicularly to the main surface of the package bottom member 4, so that the metal block 3 is provided on the package bottom member 4. The LD 1 is placed on the metal block 3 so that its optical axis is perpendicular to the bottom member 4. For this reason, it is necessary to use a sufficiently large metal block 3 that can be disposed on the bottom member 4, for example, having a thickness of about 1400 μm.

  However, when the metal block 3 is used, a process of attaching the metal block 3 to the package 4, that is, a so-called block bond assembling process is required, which complicates the production process and increases the number of members, so that defects due to assembly are likely to occur. As a result, there is a problem that the production cost becomes high.

  In addition, as shown in FIG. 2, since it is necessary to attach a metal cap 6 that covers the metal block 3, the overall size of the apparatus becomes large, and there is a problem that it is not possible to achieve downsizing, particularly reduction in thickness. there were.

  Here, without providing the metal block 3, the LD 1 is installed as a sufficient thickness necessary to install the submount 2 made of a semiconductor material, which is usually very thin, perpendicular to the bottom member 4. It is conceivable that the submount 2 is arranged on the bottom member 4 so that the optical axis of the LD 1 is perpendicular to the main surface of the bottom member 4. Since the submount 2 made of is poor in heat conduction with respect to the metal, the LD1 cannot sufficiently dissipate heat, and the LD1 cannot perform a desired operation due to heat generation. Therefore, if the structure without the metal block 3 is used, a semiconductor laser device having desired characteristics cannot be obtained.

  As described above, in the conventional semiconductor laser device, it is necessary to provide a metal block for mounting the LD, which complicates the production process, increases the production cost, and cannot be downsized. There was a problem.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a semiconductor laser device that can be manufactured at a low cost and can be reduced in size.

  A semiconductor laser device according to the present invention includes a plate-shaped member made of metal, a submount disposed on a main surface of the plate-shaped member, and an optical axis direction on the submount. A laser diode disposed parallel to the surface, and a transparent member disposed on the main surface of the plate-shaped member so as to seal the submount and the laser diode, and the transparent member has a side surface Is inclined toward the side where the laser diode is provided as it goes upward with respect to the plate-like member, and the position where the laser light emitted from the laser diode on the side surface is transmitted is The laser diode is perpendicular to the optical axis direction of the laser diode.

  According to this invention, the plate-shaped member made of metal, the submount disposed on the main surface of the plate-shaped member, and the optical axis direction on the submount is parallel to the main surface of the plate-shaped member. And a transparent member arranged on the main surface of the plate-like member so as to seal the submount and the laser diode, so that it is necessary to provide a metal block. As a result, the number of components can be reduced, the manufacturing process can be shortened, the manufacturing cost of the semiconductor laser device can be reduced, the semiconductor laser device can be provided at a low cost, and the miniaturized semiconductor laser device can be provided. .

  The transparent member is inclined toward the side where the laser diode is provided as the side surface thereof is directed upward with respect to the plate-like member, and is emitted from the laser diode on the side surface. Since the position where the laser beam to be transmitted is perpendicular to the optical axis direction of the laser diode, the laser can be removed without impairing the ease of removing the transparent member from the mold during the manufacturing process. While maintaining the optical axis direction of the light parallel to the main surface of the metal frame, it is possible to emit a laser beam from the side surface of the mold resin, and to provide a semiconductor laser device that eliminates a deviation in the emission direction of the laser beam. effective.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing a structure of a semiconductor laser device according to an embodiment of the present invention. In the figure, 1 is a laser diode (hereinafter referred to as LD), 2 is a submount having a thickness of about 150 to 250 μm, Reference numeral 41 denotes a metal frame which is a plate-shaped member made of metal, and the LD 1 is attached on the main surface of the metal frame 41 via the submount 2. At this time, the submount 2 functions to relieve stress generated during the operation of the LD 1 due to the difference in thermal expansion coefficient between the metal frame 41 and the LD 1. The thickness is adjusted so as not to interfere. 8 is a laser beam, 9 is a transparent mold resin 9 which is provided so as to cover the portion where the LD 1, submount 2, LD 1 of the metal frame 41 and the like are disposed. On the other hand, as long as it is a transparent member, a member made of another material may be used. Reference numerals 91 and 92 denote side portions of the mold resin 9, and the side portions 91 and 92 are inclined at a predetermined angle in the height direction of the frame 41 toward the direction in which the LD 1 or the like of the frame 41 is placed. . Reference numeral 10 denotes a region of the side surface portion 91 where the laser light 8 emitted from the LD 1 is transmitted. The transmission region 10 is a surface perpendicular to the main surface of the metal frame 41. The dimension of the transmission region 10 is about 0.1 to 0.3 nm in width. In addition, wire wiring etc. are abbreviate | omitted in the figure.

  Next, the manufacturing method will be described. First, an LD chip 1, a submount 2, and a metal frame 41 are prepared, and the LD chip 1 is placed on the metal frame 41 via the submount 2 so that the bottom surface of the LD chip 1 is parallel to the mounting surface of the metal frame 41. Mount on the main surface.

  Subsequently, a mold (not shown) composed of an upper mold and a lower mold having recesses is prepared, and the LD chip 1, the submount 2, and the LD chip of the metal frame 41 are placed in the recesses of the upper and lower molds. 1 is placed so as to sandwich the portion, and by injecting the resin into the mold, the outer shape of the resin is molded, and further, the resin is cured by heating, so that the LD 1 A mold resin 9 for protecting from the external environment is formed. At this time, in order to make it easy to remove the resin from the upper and lower molds after molding the side surfaces of the mold resin 9 in advance, the side surface shape of the upper and lower molds is such that the LD 1 is formed as the formed mold resin 9 is separated from the metal frame 41. It is made into the shape which becomes the shape which inclined at the predetermined angle of about 5-20 degrees toward the provided direction. Further, only the portion of the upper and lower molds corresponding to the laser light transmission region 10 of the mold resin 9 is shaped so that the formed transmission region 10 is formed as a surface perpendicular to the metal frame 41. deep. Thereafter, the mold resin 9 is extracted from the mold to obtain a semiconductor laser device as shown in FIG.

  In the semiconductor laser device of the present embodiment, by applying a voltage to the LD 1 and driving it, the laser light 8 is emitted from the emission end face of the LD 1, and the emitted laser light 8 is parallel to the metal frame 41 so that the transparent mold The light is transmitted through the transmission region 10 of the resin 9 and emitted.

  In the present embodiment, the LD 1 is placed on the main surface of the metal frame 41 via the submount 2 so that the optical axis direction, that is, the laser beam emission direction is parallel to the main surface of the metal frame 41. Since the laser beam 8 is emitted in a direction parallel to the main surface of the metal frame 41, the laser beam is emitted perpendicularly to the metal frame as described in the prior art. Thus, there is no need to provide a metal block for mounting the LD, the number of components of the semiconductor laser device can be reduced, the metal block mounting process can be eliminated, and the work process can be shortened. Further, by eliminating the metal block, the size of the entire semiconductor laser device can be reduced, and in particular, the thickness thereof can be reduced.

  In general, in the LD, the length in the optical axis direction, that is, the direction in which the laser light is emitted is longer than the thickness. Therefore, in the conventional semiconductor laser device, the LD is required to be arranged so that the optical axis direction thereof is the thickness direction of the semiconductor laser device. In the laser device, since the LD 1 can be arranged so that the thickness direction thereof is the thickness direction of the semiconductor laser device, the thickness of the semiconductor laser device can be reduced.

  Also, since LD 1 is mounted on metal frame 41 through submount 2 having a sufficiently small thickness, heat radiation during operation from LD 1 is also uniform from each region of LD 1 to metal frame 41. It is performed efficiently, and the laser characteristics are not deteriorated by the heat generated during the LD operation.

  Furthermore, in general, when molding a mold resin with an upper and lower mold, in order to easily remove the molded resin from the upper and lower molds, an LD or the like to be protected with the mold resin is placed on the side surface of the mold resin. The main surface of the metal frame is inclined at a predetermined angle, for example, 5 to 20 °, toward the side on which the LD or the like is placed. However, in this case, when the laser beam is emitted parallel to the main surface of the metal frame 41 as in the present embodiment, the laser beam 8 emitted in front of the LD 1 is refracted on the side surface of the mold resin, and the metal The light is emitted not parallel to the main surface of the frame 41. In other words, the laser beam is refracted to cause an angle shift of the optical axis of the laser beam. For example, when this laser is used for reading a disk, the emitted laser beam is discriminated using an external lens or the like. Even if an attempt is made to irradiate a predetermined position above, a deviation occurs.

  On the other hand, in the present embodiment, only the region 10 through which the laser light of the mold resin 9 transmits is a plane perpendicular to the metal frame 41, and the draft angle of the mold to the mold resin is zero, Since the other portions of the side surfaces 91 and 92 of the mold resin 9 are inclined with respect to the metal frame 41, the laser light 8 is emitted in parallel with the metal frame 41 without being refracted in the transmission region 10. In the emitted laser beam, the optical axis is not displaced due to refraction, and the other side surface portion is inclined with respect to the metal frame 41, so that the mold resin 9 can be easily extracted from the upper and lower molds. it can.

  As described above, according to the embodiment of the present invention, the LD 1 is placed on the metal frame 41 via the submount 2, and the surfaces of the LD1 and the submount 2 are covered with the transparent mold resin 9, Since the laser beam 8 is emitted in a direction parallel to the main surface of the metal frame 41, there is no need to provide a metal block as in the conventional can-type semiconductor laser device, the number of members is reduced, and the manufacturing process is reduced. The semiconductor laser device can be manufactured at a low cost by reducing the manufacturing cost of the semiconductor laser device, and the metal block can be eliminated, and the semiconductor laser device can be reduced in size, particularly reduced in thickness.

  Further, the side surfaces 91 and 92 of the mold resin 9 are inclined in the direction of the submount toward the upper side of the metal frame 41, and the region of the side surface 91 of the mold resin 9 through which the laser light is transmitted is Since the surface is perpendicular to the main surface of the metal frame 41, the optical axis of the laser beam 8 is the main surface of the metal frame 41 without impairing the ease of removal of the mold resin 9 from the mold during the manufacturing process. The laser beam 8 can be emitted from the side surface of the mold resin 9 so as to be parallel to the surface, and there is an effect that the deviation of the emission direction of the laser beam 8 can be eliminated.

  During the manufacturing process, the laser beam is emitted from the side surface of the mold resin while maintaining the optical axis direction of the laser beam parallel to the main surface of the metal frame without impairing the ease of removing the transparent member from the mold. A semiconductor laser device that can eliminate the deviation in the laser beam emission direction can be provided.

1 is a cross-sectional view showing a structure of a semiconductor laser device according to an embodiment of the present invention. It is sectional drawing which shows the structure of the conventional semiconductor laser apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser diode 2 Submount 3 Metal block 4 Bottom member 5 Metal wire 6 Metal cap 6a Opening part 7 Window part 8 Laser beam 9 Mold resin 20 Metal lead 41 Metal frame 91, 92 Side surface of mold resin 10 Laser light transmission area

Claims (1)

A plate-shaped member made of metal;
A submount disposed on the main surface of the plate-like member;
A laser diode disposed on the submount so that an optical axis direction thereof is parallel to a main surface of the plate-shaped member;
A transparent member disposed on the main surface of the plate-like member so as to seal the submount and the laser diode;
The transparent member is inclined toward the side where the laser diode is provided as the side surface thereof is directed upward with respect to the plate-like member, and laser emitted from the laser diode on the side surface. A semiconductor laser device characterized in that a light transmitting position is perpendicular to the optical axis direction of the laser diode.

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