JPS6079789A - Semiconductor laser-array device - Google Patents

Abstract

PURPOSE:To connect each element in a semiconductor laser-array electrically and severally, and to improve heat dissipating characteristics by fast sticking and fixing the upper section of the semiconductor laser-array by a mount formed from a material, which has high thermal conductivity and insulating properties. CONSTITUTION:A semiconductor laser-array 10 is constituted by four semiconductor lasers 11, and first electrodes 50 in the vicinity of active layers 12 are etched and grooves 13 reaching up to the depth of the active layers 12 are formed in the direction parallel with resonator axes 51 in the semiconductor lasers 11 so that each laser has electrical insulating properties. The second electrode 52 sides far from the active layers 12 are fusion-bonded on a heat sink 14 in the semiconductor laser-array 10. A mount 15 consisting of a high-resistance silicon wafer having high insulating properties is fitted on the semiconductor laser-array 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor laser play device in which each element of a semiconductor laser array operates independently.

In recent years, optical communication systems that use semiconductor lasers as light sources and optical fibers as transmission lines have the potential to become superior to conventional communication systems as capable of long-distance, large-capacity transmission.
Its practical application is progressing from subscriber transmission to submarine relay transmission. Furthermore, in the fields of information processing and exchange, the application of light wave technology is being considered due to the need to reduce electromagnetic induction noise and mutual induction noise. For example, in the field of information processing, with the spread of office automation equipment, etc., when data transmission is to be performed between various and numerous devices installed in a distributed manner, a method of arranging many optical fibers in parallel has been considered. . In order to make this type of optical communication system economical and highly reliable, it is necessary to arrange a large number of light-emitting elements and light-receiving elements in a plane with high density and connect them to optical fibers. be.

Among these, regarding the densification of light-emitting elements that require characteristic homogeneity, such as semiconductor lasers, Mr. Yamakoshi et al., Proceedings of the 1985 IEICE General Conference National Conference, Vol. 4, No. 949, p. 35 A I Qa A described in
There is a laser play with s/Ga A 8 multiple quantum well structure. In this laser array, each element is electrically isolated by a groove that reaches down to the multi-quantum well layer corresponding to the active layer so that each element can operate independently.

Conventionally, as a method for electrically connecting semiconductor lasers, ultrasonic bonding or thermocompression bonding using aluminum wire or gold wire with an outer diameter of about 30 μm has been used.

However, when optical fibers are arranged in an array on both sides of the output end face of a laser array, an optical signal is injected from one optical fiber, and the processed optical signal is transmitted to the other optical fiber. had the disadvantage that it became spatially difficult to connect the semiconductor laser and the mount using υ aluminum wire or gold wire using ultrasonic bonding or the like. It seems that the electrical connection of the laser array by ultrasonic bonding or the like is limited to at most two connections. Furthermore, even when laser arrays are operated simultaneously, heat generation becomes a major problem. In particular, in P-8ide-up (a method in which the semiconductor laser is fused and fixed with the active layer side separated from the heat sink), the thermal resistance increases significantly, so even if the oscillation threshold of each element is low, There is a drawback that CW operation becomes difficult because the overall power consumption becomes large.

The object of the present invention is to eliminate such drawbacks, to improve heat dissipation characteristics by electrically connecting each element of a semiconductor laser array individually, and to provide a semiconductor that can perform CW operation even in P-8ide-TJp. An object of the present invention is to provide a laser array device.

The configuration of the present invention is such that in a semiconductor laser array device comprising a plurality of semiconductor lasers fused and fixed on a heat sink and electrically isolated, a dedicated current is applied to connect the electrodes of each element of the semiconductor laser array. The semiconductor laser array is characterized in that the upper part of the semiconductor laser array is closely fixed by a mount formed of a material having high thermal conductivity and insulating properties and having a line.

In this invention, the semiconductor laser array on the heat sink is covered from above by a mount made of a material with high thermal conductivity and high insulation properties, and the semiconductor laser array reaches all the way to the active layer. The grooves provide electrical insulation between each element. This semiconductor laser
In order to operate the array for each element, a patterned current line is provided on the mount.If this semiconductor laser array is sandwiched between the mount and a heat sink, the patterned current line is provided on the mount. line w
It is possible to inject the desired current into each element through j. Furthermore, since it is held down by a mount with good thermal conductivity, the heat dissipation area is expanded and the heat dissipation characteristics are improved.

Next, the present invention will be explained in detail using the drawings.

FIG. 1 is a plan view of the embodiment @1 of the present invention, and FIG.
The front view and 3rd floor view are! ! FIG. 42 is a perspective view of the mount used in FIG. 41; The semiconductor laser array 10 of this example is:
Consisting of four semiconductor lasers 11, the first electrode 50 side near the active layer 12 is etched to form a groove that reaches the depth K of the active layer 12 so that each laser has electrical insulation properties. 13 is the common Wx screw shaft 5 of the multi-conductor laser 11
It is shaped in a direction parallel to 1. This semiconductor laser
In the array 10, the side of the electrode 52 of the sentry 2 that is far from the active layer 12 is fused onto the heat sink 14.

The mount 15 provided on this semiconductor laser array 11 uses a highly insulating, high-resistance silicon wafer. This silicon material has a relatively high thermal conductivity compared to other insulating materials (InP (indium phosphide) and Ga
Compared to As (gallium arsenide), it is 18 times higher and 22
twice as high. Therefore, if the mount 15 is closely fixed to the first polarization 50 of the semiconductor laser array 10, P
Even with the -3ide up structure, the heat dissipation characteristics will not deteriorate.

A recess 17 is formed in the mount 15 so as to increase the contact area on the surface of the mount 15 facing the first electrode 50.
and a convex portion 18 are formed, the convex portion 18 is for improving heat dissipation and electrical connection between the first electrode 50 of each semiconductor laser 11 and the contact 17, and the concave portion 7 is for a current line. 16
This is for arranging them on a plane.

In this embodiment, the uneven portion was formed by chemically etching a silicon wafer with a (001) plane, and the height difference of the uneven portion was about 15 μm. Next, 1 chromium and gold are sequentially deposited on the surface where the uneven portions are formed.

Chromium is used to improve the adhesion between silicon, which is an insulator, and gold. Next, by using photonic technology on the entire surface, unnecessary ROMs are installed so that the current line 16 of the desired length and the convex portion 18 can be electrically connected and read.
All you have to do is remove the gold.

Confucian diagram 3 (shaded area).

Further, as shown in FIG. 2, support stands 2 fixed to the bag cage 19 are provided at both ends of the mount 15 so that the mount 15 is fixed only to the semiconductor laser array 10.
It is held at 0. Electrically, the current line 1G of the mount 15 and the metal vapor deposited portion 21 of the support base 20 are fixed with solder or the like and have an equal potential. Therefore, the semiconductor lasers 11 of 4 (β1) can be operated individually because they can be connected to the drive electric circuit through the metal vapor deposited portion 2 of the support base 20.

In this embodiment, the oscillation -7 value of each semiconductor laser 11 in CW operation is 39 mA at room temperature, and even when operated simultaneously, the semiconductor laser array 10 is sandwiched between the heat sink 14 and the mount 15. Because of this, the inter-oscillation value of Okaka's semiconductor laser 11 could be kept as small as 35 mA at room temperature even though it was fixed with P-8ide up.

FIG. 4 is a perspective view of a second embodiment of the invention. In this embodiment, instead of providing an uneven portion on the mount 15 with which the semiconductor laser array 10 comes into contact, the current line 16 is
The photo ring is formed in a straight line on the surface of the marlant 15 on the opposite side to the side with which the electrode 50 contacts, using the photo ring two-flick technique. In order to electrically connect to the semiconductor laser 11, a large number of cavities 30 provided on the mount 15 may be filled with solder or a metal 31 such as In. The cavity 30 of the mount 15 can be formed by chemical etching or mechanical processing, and in this embodiment, the latter method is used. A cavity 30 with an outer diameter of 20Ii1n was fabricated on a current line of 1440 μm.

Further, although adhesive is used for convenience in connecting the mount 15 and the support base 20, the connection is not particularly limited. map ζ
, Current line 1! Although the connection between S16 and the metal vapor deposited portion 21 on the support stand 20 was fixed using solder 32, this is not limited thereto either. In this embodiment, since the mount 15 and the semiconductor laser array 10 are closely fixed, the heat dissipation characteristics are good, and the oscillation threshold of this semiconductor laser at room temperature can be kept to a low 35 mA in CW operation. .

In these embodiments, a high-resistance silicon wafer is used as the mount 15, but an insulating material with high thermal conductivity such as Be0 (beryllium oxide) or 5iC (silicon carbide) ceramic may also be used.

Furthermore, although the semiconductor laser array 10 is a combination of four semiconductor lasers 11, this configuration can also adequately cope with the case of an array of ten or more semiconductor lasers 11.
I can do that.

In addition, in the following embodiments, grooves are used to electrically isolate the line elements, but the method is not particularly limited, and two elements may be separated by, for example, proton irradiation. Further, although chromium and gold are used as the vapor-deposited metals for the current line 16 for convenience, a combination of titanium, platinum, and gold, which has excellent adhesion strength, may be used. Furthermore, in order to further improve the electrical connection between the current line 16 and the first electrode 50, in the case of the first embodiment, the convex portion 18 is made of a metal that easily reacts with gold, such as 8n (tin), In( The two may be fused and fixed by partial vapor deposition of indium (indium) or the like. Note that in the second embodiment,
For example, the semiconductor laser array 10 and the mount 15 may be fused and fixed by inserting In into one of the cavities 30 and heating it. Further, in the second embodiment, the mount 15 and the support base 20 are fixed with adhesive, but the mount 1
The heat dissipation characteristics may be further improved by attaching metal to the back side of the support base 20 and fusing it with the support base 20.

[Brief explanation of drawings]

FIG. 1 is a plan view of the first embodiment of the present invention, and FIG. 2 is a plan view of the first embodiment of the present invention.
3 is a front view of the figure, FIG. 3 is a perspective view of the mount used in FIG. 1, and FIG. 4 is a perspective view of a second embodiment of the present invention. In the figure, 10... semiconductor laser array, 11...
... Semiconductor laser, 12... Active layer, 13...
...Groove, 14...Heat sink, 15...
...Mount, 16.Old...Current line, 17...
...Concave part, 18...Convex part, 19...Package for, 20...Mountain/support stand, 21...Metal deposition part, 30...Cavity part , 31...Metal, 32...Curved solder, 50...First electrode, 51
...Resonator axis, 52 ... Second electrode,
It is.

Claims (1)

[Claims] A semiconductor laser play device comprising a plurality of semiconductor laser elements fused and fixed on a heat sink and electrically isolated, each having a dedicated current line to which an electrode of each laser element of the semiconductor laser array is connected. 7. A semiconductor laser array device according to claim 7, wherein an upper portion of the semiconductor laser array is tightly fixed by a mount made of a material having high thermal conductivity and insulating properties.