JPH067631B2 - Semiconductor laser device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a semiconductor laser device that can be used as a light source for optical information processing and the like.

2. Description of the Related Art In recent years, semiconductor laser devices have many excellent features such as small size, high efficiency, and modulation by drive current. Therefore, they are used as light sources for optical communication and optical information processing. ing.

Hereinafter, a conventional semiconductor laser device as described above will be described with reference to the drawings.

FIG. 3 shows a front view of the configuration of a conventional semiconductor laser device. In FIG. 3, reference numeral 1 is a semiconductor laser chip that actually emits laser light. A silicon submount 2 serves to fix the semiconductor laser chip 1 and dissipate heat. Reference numeral 3 is a stem serving as a base of the semiconductor laser device, and reference numeral 4 is a PIN photodiode for generating a monitor current. Reference numeral 5 is a PIN photodiode electrode that guides a monitor current to the outside, and 6 is a semiconductor laser electrode that supplies a current to the semiconductor laser chip 1.

The operation of the semiconductor laser device configured as described above will be described below.

The silicon submount 2 is bonded on a flat surface provided on the stem 3, and acts as an intermediary for bonding between the semiconductor laser chip 1 and the stem 3. The silicon submount 2 has a function of relaxing the difference in thermal expansion coefficient between the semiconductor laser chip 1 and the stem 3 and a function of rationalizing the assembly process. The silicon submount 2 is bonded to approximately the center of the plane of the stem 3, and the semiconductor laser chip 1 is bonded to approximately the center of the silicon submount 2.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described configuration, there is no mark for positioning the semiconductor laser chip 1 in the center of the stem 3, and the angle alignment of the optical axes can be performed with the semiconductor laser chip 1 and the silicon sub-chip. It can be done only by aligning the front surface of the mount 2. Therefore, there is a problem that the optical axis becomes inaccurate. In addition, the silicon submount 2 has a problem that the thermal conductivity is not so large, the thermal resistance is large, and if the silicon submount 2 is made thin to reduce the thermal resistance, the assembling workability is deteriorated. .

In view of the above problems, the present invention provides a semiconductor laser device capable of accurately aligning the optical axes and reducing thermal resistance.

Means for Solving the Problems In order to solve the above problems, in the semiconductor laser device of the present invention, a silicon submount is bonded to a copper stem having a step lower than the thickness of the silicon submount in contact with the step side surface. A semiconductor laser chip is bonded to the front corner of the step of the copper stem of the silicon submount.

Operation With this configuration, the semiconductor laser chip can be accurately bonded to a fixed position on the copper stem with little angular deviation, and at the same time, the semiconductor laser chip and the copper stem do not depend on the thickness of the silicon submount. ,
Since it is located at a very short distance, it is possible to suppress the thermal resistance to a small level.

Example 1 FIG. 1 is a front view of an embodiment of the semiconductor laser device of the present invention, and FIG. 2 is a perspective view thereof, both of which omit the package. In these figures, 3 is a copper stem having a step slightly lower than the thickness of the silicon submount 2 used on the bonding stage. The semiconductor laser chip 1 is bonded by aligning the side surface with the front corner of the silicon submount 2, and the silicon submount 2 is bonded so that the front surface of the copper stem and the side surface on the step side are aligned. When the silicon submount 2 to which the semiconductor laser chip 1 is bonded as described above is bonded to the copper stem 3, the light emitting portion of the semiconductor laser chip 1 automatically moves to the center of the copper stem 3 in the copper stem 3. Its dimensions are designed to be located.

In addition, in the above-mentioned embodiment, when viewed from the front, the left side is lowered as the step, but there is no inconvenience even if the right side is lowered due to the process.

As described above, according to the present invention, by bonding the semiconductor laser chip to the corner portion of the silicon submount, the two surfaces can be bonded together, and the silicon submount and the semiconductor laser chip are exactly the same. Since it is oriented in the direction, the optical axis is unlikely to shift, and positioning is easy and accurate. Furthermore, by bonding this silicon submount to a copper stem having a step, the optical axis can be automatically adjusted, and even when the thickness of the submount is large, the semiconductor laser chip and the copper stem are close to each other. It is possible to reduce the thermal resistance. Further, in manufacturing, since the only change to adopt the present invention is to change the shape of the copper stem, a great industrial effect can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of a semiconductor laser device of the present invention, FIG. 2 is a perspective view thereof, and FIG. 3 is a front view of a conventional semiconductor laser device. 1 ... Semiconductor laser chip, 2 ... Silicon submount, 3 ... Copper stem, 4 ... PIN photodiode,
5 ... PIN photodiode electrode, 6 ... Semiconductor laser electrode, 7 ... Gold wire.

Claims (2)

[Claims] 1. A semiconductor laser chip is bonded to a corner of a silicon submount such that an emission surface and one side surface of the semiconductor laser chip are flush with two side surfaces of the silicon submount. Semiconductor laser device. 2. The silicon submount is bonded in contact with the step side surface on the lower surface of the stem having a step having the same thickness as or lower than the thickness of the silicon submount. 2. A semiconductor laser device according to claim 1.