JPH02281784A - Semiconductor laser device - Google Patents

Abstract

PURPOSE:To suppress the deterioration by not fixing the side of the luminous end face of a semiconductor chip by bonding material. CONSTITUTION:The side of the luminous end face of a semiconductor chip 4 is not fixed by a bonding material 2. That is, the width of an electrode 3 formed in the semiconductor chip 4 is made smaller than the size of the semiconductor chip 4, or the width of the bonding part 2a of the mounting member 2 to mount the semiconductor chip 4 is made smaller than the size of the semiconductor laser chip 4. Hereby, great stress is not applied to the luminous end face where many crystal dislocations exist, and generation of defects and deterioration of it are suppressed and the reliability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a semiconductor laser device used in optical information processing, optical communication, etc.

BACKGROUND OF THE INVENTION In recent years, as the performance of semiconductor laser devices has improved, the field of use thereof has been rapidly expanding. However, semiconductor laser devices have the characteristic that deterioration progresses during operation due to dark line defects (OLD) and dark spot defects (DSD) that occur in their active regions.As a result, semiconductor laser devices have a long lifespan. Various efforts have been made to achieve this.A conventional configuration is shown in FIG. 24 were bonded (Reference H, Koyama, Appl, Phys, t
ett,.

VOl, 43. No. 8, P733 (1983)
) , CoI) The thermal expansion coefficient of the structure Nior and 3i, which is the material of the submount 22, is close to that of GaAs, which is the material of the semiconductor laser chip 24, and when the semiconductor laser chip 24 is directly bonded to the Cu heat sink 21. Compared to this, the stress applied to the semiconductor laser chip 24 is smaller, and a longer life can be expected.

Problems to be Solved by the Invention However, the above conventional configuration has the following problems. In other words, it has been found through three-dimensional stress analysis that a large amount of stress occurs on the edges around the bonding surface, and therefore, the light emitting end face, which shares the same side with the bonding surface of the semiconductor laser chip 24, also receives larger stress than the inside of the chip. will be applied. Furthermore, since there are many crystal dislocations that are the core of dark line defects and dark spot defects on the light emitting end face,
Deterioration of conventional semiconductor laser devices often occurs from the light emitting end facet.

Therefore, an object of the present invention is to provide a semiconductor laser device that can solve the above problems.

Means for Solving the Problems In order to solve the above problems, the semiconductor laser device of the present invention is such that the side of the light emitting end face of the semiconductor laser chip is not fixed by a bonding material. The width of the electrodes formed on the laser chip is smaller than the size of the semiconductor laser chip, and the width of the bonding part of the mount member on which the semiconductor laser chip is mounted is smaller than the size of the semiconductor laser chip. .

Effect: According to the above configuration, no large stress is applied to the light-emitting end face where many crystal dislocations exist, so the occurrence and growth of dark line defects and dark spot defects is suppressed, thereby improving the reliability of the semiconductor laser device. I can do it.

EXAMPLE A first example of the present invention will be described below with reference to FIG.

Reference numeral 1 denotes a Cu heat sink. A 3i submount (mounting material) 2 is bonded to the upper surface of the Cu heat sink, and a semiconductor laser chip 4 is further bonded to the upper surface of the submount 2 via an electrode 3. Further, the edges of the electrodes 3 formed on the surface of the semiconductor laser chip 4 are each made smaller so as to be located 30 μm inside the sides of the light emitting end face of the semiconductor laser chip 4.

Also, this electric f! The thickness of No. 3 is 3 μm or more, and the thickness of the bonding material is 1 to 2 μm.

Therefore, the sides of the light emitting end face of the semiconductor laser chip 4 are not fixed by the bonding material, and it is possible to prevent large stress from being applied to the light emitting end face.

Next, a second embodiment will be explained based on FIG. 2.

In the first embodiment, the size of the electrode 3 is reduced, but in this second embodiment, the size of the electrode 3 of the Si submount 2 is reduced.
The bonding portion 2a between the two is made smaller. That is, the bonding part 2a, which is the upper part of the 3i submount 2, is etched to a size that is 30 μm inward from the periphery of the electrode 3 formed on the lower surface of the semiconductor laser chip 4. Therefore, in this case as well, the sides of the light emitting end face of the semiconductor laser chip 4 are not fixed by the bonding material, and application of large stress to the light emitting end face is prevented.

Effects of the Invention As described above, according to the semiconductor laser device of the present invention, the sides of the light-emitting end face of the semiconductor laser chip are not fixed by bonding material, so that no large stress is applied to the light-emitting facet where many crystal dislocations exist. Therefore, the occurrence and growth of dark line defects and dark spot defects is suppressed, and the reliability of the semiconductor laser device can be improved.

[Brief explanation of drawings]

FIG. 1 is a side view showing a first embodiment of the semiconductor laser device of the present invention, FIG. 2 is a side view showing the second embodiment, and FIG.
The figure is a side view of a conventional example. DESCRIPTION OF SYMBOLS 1...Cu heat sink, 2...Si submount, 2a...bonding part, 3...electrode, 4...
semiconductor laser chip. Figure 3 shows agent Yoshihiro Moriki.

Claims (1)

[Claims] 1. A semiconductor laser device in which the side of the light emitting end face of the semiconductor laser chip is not fixed with a bonding material. 2. The semiconductor laser device according to claim 1, wherein the semiconductor laser device is bonded to the mounting member via an electrode having a width smaller than the size of the semiconductor laser chip. 3. The semiconductor laser device according to claim 1, wherein the semiconductor laser chip is bonded to a mounting member whose width is smaller than the size of the semiconductor laser chip.