JPH0864902A - Stack semiconductor laser device assembling method and stack semiconductor laser device - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a stack type semiconductor laser device capable of stably outputting a predetermined high power optical output for a long period of time. [Structure] The semiconductor laser chip 1 is die-bonded to a predetermined position on the upper surface of a heat sink 6, and the semiconductor laser chip 2 is placed on the upper surface at a predetermined position on the top surface of a table-shaped metal spacer 10 (20, 30). Stack elements 50a, 50 formed by die-bonding (3, 4)
b and 50c are replaced by the table-shaped metal spacer 10
The legs of (20, 30) are adhered using the insulating adhesive 8 to sequentially stack the semiconductor laser chips 1 to 4 to assemble the stacked semiconductor laser device 100.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling a stack type semiconductor laser device and a stack type semiconductor laser device, and more particularly to assembling a stack type semiconductor laser device capable of accurately positioning and stacking a plurality of semiconductor laser chips. The present invention relates to a method and a stack type semiconductor laser device that outputs a predetermined high power optical output stably for a long period of time.

[0002]

2. Description of the Related Art In recent years, as semiconductor laser devices have become more sophisticated, stack type semiconductor laser devices have been developed in which a plurality of semiconductor laser chips are stacked in order to obtain high-power optical output.

FIG. 5 is a front view showing the structure of this conventional stack type semiconductor laser device. In FIG.
Is a stack type semiconductor laser device, in which the semiconductor laser chip 1 is die-bonded (soldered) on the heat sink 6 by the solder 7, and similarly, the semiconductor laser chip 2 and the semiconductor laser chip 2 are mounted on the semiconductor laser chip 1. The semiconductor laser chip 3 and the semiconductor laser chip 4 are die-bonded (soldered) on the semiconductor laser chip 3 and the semiconductor laser chip 3, respectively, and the wire 5 such as a gold wire is wire-bonded to the upper surface electrode 4a of the semiconductor laser chip 4. Is configured. Where 1
a, 2a and 3a are upper surface electrodes of the semiconductor laser chips 1 to 3 and 1b, 2b, 3b and 4b are semiconductor laser chips 1 respectively.
To 4 lower electrodes, 1c, 2c, 3c and 4c are light emission surfaces of the semiconductor laser chips 1 to 1d, 2d, 3d and 4d.
Is a light emitting region (active layer) of each of the semiconductor laser chips 1 to 4. Each of the semiconductor laser chips 1 to 4 emits a laser beam in a direction perpendicular to the light emitting surfaces 1c, 2c, 3c and 4c (that is, a direction perpendicular to the paper surface of FIG. 5). The wire 5 such as a gold wire is connected to a power source (not shown), and the heat sink 6 is connected to a power source (not shown) by a required wiring (not shown).

Next, the operation will be described. This stack type semiconductor laser device 1000 is generally used for a laser radar light source and the like, and outputs a watt class optical output by a pulse operation. Normally, when one semiconductor laser chip is continuously operated, the semiconductor laser chip is thermally saturated with a certain level of optical output, and thereafter, the optical output is decreased conversely. On the other hand, in this stack type semiconductor laser device 1000, a plurality of semiconductor laser chips 1 to 4 are simultaneously operated by a pulse operation to obtain a total optical output of the individual semiconductor laser chips 1 to 4. It can output watt class high power optical output. In such a stack type semiconductor laser device 1000, in order to normally collect the laser light emitted from the plurality of semiconductor laser chips 1 to 4, a condenser lens (not shown) is provided in front of the light emitting surface of these chips. No) is arranged.

[0005]

Although the above-mentioned conventional stack type semiconductor laser device 1000 is assembled as described above, the following problems occur.

That is, since the plurality of semiconductor laser chips 1 to 4 are usually chips of the same size, when these chips 1 to 4 are sequentially stacked and die-bonding is performed between the vertically overlapping chips. , It is difficult to position each chip with high accuracy. For this reason,
The obtained stack type semiconductor laser device 1000 is shown in FIG.
(a) (top view of stack type semiconductor laser device 1000), and FIG. 6 (b) (stack type semiconductor laser device 10).
(Front view of 00), the light emitting surfaces 1c, 2c, 3c, and 4c of the chips 1 to 4 are deviated in direction,
The laser light emitted from the light emitting regions (active layers) 1d, 2d, 3d, and 4d of 4 to 4 may be emitted in different directions, and a predetermined high power optical output can be obtained. There is a problem that a laser device cannot be obtained with good reproducibility.

Further, since the chips are soldered on the chips, the solder which is used for soldering the lower chip and has already solidified is heated together with the lower chip when the upper chip is soldered. In some cases, the chips already positioned on the lower side may be moved due to the melting and melting again. In this case as well, the stack type semiconductor laser device 1000 obtained has the structure shown in FIGS. b)
As shown in FIG.
The directions of 3c and 4c are deviated, and the laser beams emitted from the light emitting regions (active layers) 1d, 2d, 3d and 4d of the chips 1 to 4 are emitted in different directions. This problem can be solved by using a solder having a melting point lower than that of the solder used for die bonding the lower chip as the solder used for die bonding the upper chip. However, when a plurality of (three or more) chips are sequentially stacked and die-bonded, it is practically extremely difficult to prepare a plurality of (three or more) solders having melting points having such a relationship. is there.

Further, as shown in FIG. 6B, during the die bonding work of the chips 1 to 4 by the solder 7, the molten solder 7 wraps around the side surfaces of the chips 1 to 3 and The obtained stack type semiconductor laser device 1000 may come into contact with the active layer exposed on the side surface.
However, there is a problem that the solder 7 and the active layers of the chips 1 to 3 are electrically short-circuited during the operation, and a predetermined operation cannot be performed.

Further, the light emitting region (active layer) of the chips 1 to 3
Since the distance between 1d, 2d, 3d and the solder 7 is short,
The light emission regions (active layers) 1d, 2d, and 3d are stressed by the stress due to the solidification of the solder 7, and the obtained stack type semiconductor laser device 1000 has each of the chips 1 to 1
3 has a low reliability, and there is a problem that a predetermined operation cannot be stably performed for a long time.

In the conventional stack type semiconductor laser device 1000, the chip 1 contacting the heat sink 6 is radiated (cooled) by the heat sink 6 during its operation. The heatsinks 3 and 4 are not radiated (cooled) by the heatsink 6, resulting in performance deterioration due to temperature rise, and there is a problem that a predetermined operation cannot be stably performed for a long period of time.

The present invention has been made to solve the above problems, and a stack type semiconductor laser device capable of assembling a stack type semiconductor laser device outputting a predetermined high power optical output with good reproducibility. The purpose is to obtain an assembly method of.

Still another object of the present invention is to provide a stack type semiconductor laser device in which each chip operates stably for a long period of time, and a predetermined high power optical output can be stably output for a long period of time, and an assembling method thereof. The purpose is to get.

[0013]

A method of assembling a stack type semiconductor laser device according to the present invention (claim 1) includes a step of die-bonding a semiconductor laser chip to an upper surface of a heat sink, and one semiconductor laser chip A step of assembling a plurality of stacking elements formed by die-bonding to the upper surface of the top plate portion of a single table-shaped metal spacer composed of a plate portion and a plurality of leg portions; After fixing the plurality of leg portions of one stacking element of the stacking element via the insulating layer, respectively, on the top surface of the top plate portion of the one stacking element, the plurality of stacking elements of A plurality of other stacking elements different from the one stacking element are arranged on the upper side, but the plurality of legs are arranged on the lower side. Stacked by fixing via respective insulating layer on the upper surface of the plate portion, and a step of stacking the elements for the plurality of stacks, the semiconductor laser chip die-bonded on the upper surface of the heat sink,
And a stack type semiconductor laser device in which a plurality of semiconductor laser chips forming each of the plurality of stacking elements are stacked.

In the stack type semiconductor laser device according to the present invention (claim 2), a heat sink having a semiconductor laser chip die-bonded to the upper surface thereof, and one semiconductor laser chip are formed from a top plate portion and a plurality of leg portions. A stacking element formed by die-bonding the top surface of the table-shaped metal spacer to the stacking element, and one stacking element of the stacking elements on the top surface of the heat sink. A plurality of legs are respectively fixed via an insulating layer, and a plurality of other stacking elements different from the one stacking element of the plurality of stacking elements on the top surface of the top plate portion of the one stacking element. Although the stacking element is arranged on the upper side of the stacking element, the plurality of legs are fixed on the upper surface of the top plate of the stacking element through insulating layers, respectively. It piled up by being,
It is characterized in that the semiconductor laser chip die-bonded to the upper surface of the heat sink and a plurality of semiconductor laser chips constituting each of the plurality of stacking elements are stacked.

Further, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 3), the table-shaped metal spacer is bonded to the top plate portion and the leg portion which are separate bodies. It is characterized by having been obtained.

Further, a stack type semiconductor laser device according to the present invention (claim 4) is obtained by bonding the table-shaped metal spacer to the top plate portion and the leg portion which are separate bodies from each other. It is characterized by having been made.

Further, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 5), the step of die bonding the semiconductor laser chip to the upper surface of the heat sink using the first solder, and one semiconductor laser chip. A step of obtaining a stacking element which is die-bonded on the upper surface of one plate-shaped metal spacer by using the first solder, and on the upper surface electrode of the semiconductor laser chip die-bonded on the upper surface of the heat sink. A step of stacking a plurality of the stacking elements by sequentially die-bonding the lower surface of the metal spacer to the bonding surface using a second solder having a melting point lower than that of the first solder, And a stack type semiconductor in which a plurality of semiconductor laser chips constituting each of the plurality of stacking elements are stacked. It is characterized in that the assembly of the laser device.

Further, in the stack type semiconductor laser device according to the present invention (claim 6), the first structure is provided on the upper surface of the heat sink.
A semiconductor laser chip die-bonded using the solder, and a plurality of stacking elements formed by die-bonding one semiconductor laser chip to the upper surface of one plate-shaped metal spacer using the first solder. The plurality of stacking elements have a lower surface of the metal spacer as an adhesive surface on an upper surface electrode of a semiconductor laser chip die-bonded to an upper surface of the heat sink and a melting point of the first solder. And die-bonded one after another using a second solder having a low melting point,
It is characterized in that the semiconductor laser chip die-bonded to the upper surface of the heat sink and a plurality of semiconductor laser chips constituting each of the plurality of stacking elements are stacked.

Further, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 7), the step of die bonding the semiconductor laser chip to each step of the stepped surface of the heat sink having the stepped surface. And stacking a plurality of semiconductor laser chips to assemble a stack type semiconductor laser device.

Further, in the stack type semiconductor laser device according to the present invention (claim 8), a semiconductor laser chip is die-bonded to each step of the stepped surface of a heat sink having a stepped surface, and a plurality of semiconductor laser chips are formed. The semiconductor laser chips are stacked to each other.

[0021]

In the method of assembling the stack type semiconductor laser device according to the present invention (claim 1), a plurality of table-shaped metal spacers are stacked on the upper surface of the heat sink,
Since the semiconductor laser chips are die-bonded to the upper surface of the heat sink and the upper surface of the top plate of each of the plurality of table-shaped metal spacers, each chip can be accurately positioned on these upper surfaces. The semiconductor laser chips can be stacked so that the light emitting surfaces of the chips are surely oriented in the same direction. Further, since solder is not laid on the upper surface electrode of each chip, the active layer exposed on the side surface of each chip does not come into contact with the solder, and stress is not applied to the light emitting region (active layer).

Further, in the stack type semiconductor laser device according to the present invention (claim 2), the upper surface of the heat sink and the top plate portion of each of the plurality of table-shaped metal spacers stacked on the upper surface of the heat sink are provided. Since the semiconductor laser chip is die-bonded to the upper surface, each chip is radiated by a heat sink or a table-shaped metal spacer. In addition, since solder is not laid on the upper surface electrode of each chip, the solder does not come into contact with the active layer exposed on the side surface thereof, and the active layer and solder do not electrically short-circuit. In addition, since solder is not laid on the upper surface electrode of each chip, stress is not applied to the light emitting region (active layer) of the chip, resulting in high reliability.

Furthermore, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 3), the table-shaped metal spacers in which the top plate and the legs are formed separately are used. Since the table-shaped metal spacers are assembled by adhering the top plate portion and the leg portions to each other, when the table-shaped metal spacers are integrated, the process for obtaining them is complicated. However, this can be solved.

Further, in the stack type semiconductor laser device according to the present invention (claim 4), the table-shaped metal spacer is obtained by adhering the top plate portion and the leg portion which are separate bodies from each other. Therefore, it is possible to use one having a large thickness as the leg portion, and when the one-piece member is used as the table-shaped metal spacer, the leg portion is thin by the processing for obtaining this, There was a problem that the mechanical strength was weak, but this can be solved.

Further, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 5), one semiconductor laser chip is die-bonded onto one plate-shaped metal spacer using the first solder. Create a plurality of stacking elements made by,
The second solder having a melting point lower than the melting point of the first solder is sequentially stacked on the upper surface electrode of the semiconductor laser chip die-bonded to the upper surface of the heat sink using the first solder. Since the stack type semiconductor laser device is assembled by die-bonding using the plurality of stack elements,
The plurality of stacks each positioned at a predetermined position on the upper surface of the one metal spacer by sequentially stacking the side surfaces of the one metal spacer along the flat surfaces of the other members. The light emitting surfaces of the one semiconductor laser chip forming the device for use are arranged so as to surely face the same direction.

Further, in the stack type semiconductor laser device according to the present invention (claim 6), one semiconductor laser chip is provided on the upper surface electrode of the semiconductor laser chip die-bonded on the heat sink using the first solder. At the predetermined position on a plate-shaped metal spacer.
A plurality of stacking elements formed by die bonding using the above solder are stacked, and the upper and lower elements are die bonded using the second solder having a melting point lower than the melting point of the first solder. From the above, the plurality of stacking elements can be accurately positioned and arranged, whereby the light emitting surfaces of the plurality of one semiconductor laser chips forming each of them can be arranged on the heat sink. The bonded semiconductor laser chip and the light emitting surface are arranged so as to surely face the same direction. Also, each chip has a heat sink under it,
Alternatively, heat is dissipated by the plate-shaped metal spacers, and performance deterioration due to temperature rise can be prevented.

Further, in the method for assembling the stack type semiconductor laser device according to the present invention (claim 7), the semiconductor laser chip is die-bonded to each step of the stepped surface of the heat sink having the stepped surface. As a result, the stack type semiconductor laser device is assembled without directly stacking a plurality of semiconductor laser chips, so that each chip can be accurately positioned in each step of the stepped surface, and the light of each chip can be accurately positioned. It is possible to stack the emission surfaces so as to surely face the same direction. Further, since solder is not laid on the upper surface electrode of each chip, the active layer exposed on the side surface of each chip does not come into contact with the solder, and stress is not applied to the light emitting region (active layer).

Further, in the stack type semiconductor laser device according to the present invention (claim 8), a semiconductor laser chip is die-bonded to each step of the stepped surface of the heat sink having the stepped surface. Therefore, each chip is radiated by the heat sink, and the performance deterioration due to the temperature rise can be prevented. Further, since no solder is laid on the upper surface electrode of each chip, the solder does not come into contact with the active layer exposed on the side surface thereof, and the active layer and solder do not electrically short-circuit. In addition, since solder is not laid on the upper surface electrode of each chip, stress is not applied to the light emitting region (active layer), resulting in high reliability.

[0029]

EXAMPLES Example 1 1 is a front view showing the structure of a stack type semiconductor laser device according to Embodiment 1 of the present invention (FIG. 1 (a)),
FIG. 1 is an exploded perspective view (FIG. 1 (b)) showing the structure of a stacking element that constitutes this stack type semiconductor laser device. In the figure, the same reference numerals as those in FIG. 4 denote the same or corresponding portions, 5a to 5d are wires, 8 is an insulating adhesive, 10, 2
0 and 30 are lumps of metal with excellent heat dissipation such as Ag and Cu,
A table-shaped metal spacer having a square top plate portion produced by processing, 50 is a stacking element, 100
Is a stack type semiconductor laser device. Here, one end (not shown) of the wire 5a is electrically connected to the table-shaped metal spacer 10, one end (not shown) of the wire 5a is electrically connected to the table-shaped metal spacer 20, and the wire 5c is not shown. One end is electrically connected to the table-shaped metal spacer 30, and the wire 5d is connected to a power source (not shown) at one end (not shown). The heat sink 6 is connected to the power source (not shown) by wiring not shown. In this figure, the upper surface electrodes and the lower surface electrodes of the semiconductor laser chips 1 to 4 are not shown.

The operation of the stack type semiconductor laser device 100 of the present embodiment having such a structure is basically the same as that of the conventional device 1000, and is connected in series between the wire 5d and the heat sink 6 by the current flowing from the power supply. The semiconductor laser chips 1 to 4 simultaneously oscillate. Then, the laser light emitted from each of the semiconductor laser chips 1 to 4 is condensed by a condenser lens (not shown) and becomes a high-power optical output.

Hereinafter, the stack type semiconductor laser device 100 will be described.
The assembling process will be described. First, as shown in Fig. 1 (b),
At a predetermined position on the top surface of the table-shaped metal spacer 10, the semiconductor laser chip 2 is attached to the light emitting surface 2c.
Is parallel to the predetermined end surface 10a of the top plate of the table-shaped metal spacer 10 and is die-bonded (soldered) so that its lower surface electrode (not shown) adheres to the upper surface of the top plate. , The stacking element 50a is obtained.

In the same manner as described above, the semiconductor laser chip 3
Is stacked on the top surface of the table-shaped metal spacer 20 by die bonding, and the semiconductor laser chip 4 is attached to the stacking element 50b.
A stacking element 50c is formed by die-bonding on the upper surface of the top plate part.

Next, the stacking element 50a is formed on the upper surface of the heat sink 6 to which the semiconductor laser chip 1 is die-bonded (soldered) at a predetermined position on the upper surface.
Is placed so that the light emitting surface 1a of the semiconductor laser chip 1 and the light emitting surface 2a of the semiconductor laser chip 2 constituting the stacking element 50a are parallel to each other. Here, the legs of the table-shaped metal spacer 10 are insulated so that the semiconductor laser chip 1 is located under the top plate of the table-shaped metal spacer 10 that constitutes the stacking element 50a. The adhesive 8 adheres to the upper surface of the heat sink 6.

Next, the stacking element 50b is formed on the top surface of the table-shaped metal spacer 10 which constitutes the stacking element 50a placed on the upper surface of the heat sink 6. The leg portion of the table-shaped metal spacer 20 is attached to the upper surface of the top plate portion of the metal spacer 10 by using an insulative adhesive 8 to mount it. Here, the stacking element 50b
The end face of the table-shaped metal spacer 10 parallel to the light emitting face 2a of the semiconductor laser chip 2 is parallel to the end face of the table-shaped metal spacer 20 parallel to the light emitting face 3a of the semiconductor laser chip 3. So that it can be placed.

Next, the stacking element 50b and the semiconductor laser chip 3 of the table-shaped metal spacer 20 are formed on the upper surface of the top plate of the table-shaped metal spacer 10 which constitutes the stacking element 50a. The end face parallel to the light emission face 3a of the above is placed so as to be parallel to the end face of the table-shaped metal spacer 10 parallel to the light emission face 2a of the semiconductor laser chip 2. here,
The legs of the table-shaped metal spacer 20 are adhered to the upper surface of the top plate of the metal spacer 10 using an insulating adhesive 8.

Next, the stacking element 50c and the semiconductor laser chip 4 of the table-shaped metal spacer 30 are placed on the top surface of the top plate portion of the table-shaped metal spacer 20 constituting the stacking element 50b. The end face parallel to the light emission face 4a of the above is placed so as to be parallel to the end face of the table-shaped metal spacer 20 parallel to the light emission face 3a of the semiconductor laser chip 3. here,
The legs of the table-shaped metal spacer 30 are adhered to the upper surface of the top plate of the metal spacer 20 using an insulating adhesive 8.

Next, wires 5a to 5d made of gold or the like are wire-bonded to the respective upper surface electrodes of the semiconductor laser chips 1 to 4, and then the wire-bonded wires 5a to the upper surface electrode of the semiconductor laser chip 1 are formed into a table-shaped metal. A wire 5b electrically connected to the spacer 10 made of metal and wire-bonded to the upper electrode of the semiconductor laser chip 2 is electrically connected to the metal spacer 20 having a table shape and wire-bonded to the upper electrode of the semiconductor laser chip 3. 5c is electrically connected to the table-shaped metal spacer 30.

Finally, the wire 5d wire-bonded to the upper surface electrode of the semiconductor laser chip 4 and the heat sink 6
Is connected to a power source, the stack type semiconductor laser device 100 shown in FIG. 1 (a) is obtained.

In the above steps, wire bonding to the upper surface electrodes of the semiconductor laser chips 1 to 4 was performed after stacking the stacking elements 10, 20, 30.
After the semiconductor laser chip 1 is die-bonded, a wire is bonded to the upper surface electrode of the semiconductor laser chip 1, and every time the stacking elements 10, 20, 30 are stacked in order, the wires are sequentially connected to the upper surface electrodes of the semiconductor laser chips 1 to 3. Bonding may be performed.

As described above, in the present embodiment, the emitted laser light is directed in the predetermined direction, that is, the light emitting surface is directed in the predetermined direction, on the upper surface of the top plate portion of one table-shaped metal spacer 10, 20, 30. Stacking elements 50a, 50c, 50b, which respectively mount the semiconductor laser chips 2, 3, 4 positioned so as to face each other, are sequentially formed on the upper surface of the heat sink 6 on which the semiconductor laser chip 1 is die-bonded. Since the stack type semiconductor laser device 100 formed by stacking the semiconductor laser chips 1 to 4 is assembled by stacking the semiconductor laser chips 1 to 4, each of the plurality of semiconductor laser chips 1 to 4 is positioned with high precision.
Each of these plurality of semiconductor laser chips 1 to 4 is
It is possible to stack so that the light emission surfaces of ~ 4 surely face the same direction. Moreover, since solder is not laid on the upper surface electrodes of the chips 1 to 3, the solder does not contact the active layer exposed on the side surface of the chips 1 to 3, and
Light emitting regions (active layers) 1a, 2a, 3a of the chips 1 to 3
There will be no stress. Also, each chip 1 to 4
In the operation, each of them is efficiently radiated by the heat sink 6 and the table-shaped metal spacers 10, 20, 30. Therefore, according to this embodiment, each of the chips 1 to 4 can stably operate for a long period of time, and a stack type semiconductor laser device 100 capable of stably outputting a predetermined high power optical output for a long period of time can be obtained with good reproducibility. You can

Example 2 2 is a front view showing a structure of a stack type semiconductor laser device according to a second embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding portions, and 11, 21, 31 are quadrangular shapes. A table-shaped metal spacer having a top plate portion, which is the table-shaped metal spacer 10, 20, 3 used in the first embodiment.
Although 0 was obtained as an integrated body by processing the metal ingot, these are the leg portions 11a (21a, 31a) and the top plate portion 11b (21b, 21b, 21b, 21b) obtained by individually processing the metal ingots.
31b).
Reference numeral 200 denotes a stack type semiconductor laser device. Here, one end (not shown) of the wire 5a is electrically connected to the top plate portion 11b, one end (not shown) of the wire 5b is electrically connected to the top plate portion 21b, and one end (not shown) of the wire 5c is the top plate portion 31b. The wire 5d is electrically connected to a power source (not shown) at one end (not shown). The heat sink 6 is connected to the power source (not shown) by wiring not shown. In this figure, the upper surface electrodes and the lower surface electrodes of the semiconductor laser chips 1 to 4 are not shown.

In the stack type semiconductor laser device 100 of the first embodiment, the table-shaped metal spacers 10, 20, 30 obtained by processing the metal ingot into the table shape are used. It is difficult to process it into a table shape with high precision, and the leg portions of the table-shaped metal spacers 10, 20, 30 become too thin, which weakens the mechanical strength of itself. There are drawbacks.

The present embodiment is designed to eliminate such drawbacks, and the leg portions 11a (21a, 31a) and the top plate portions (11b, 21b, 31b) are individually manufactured, and these are adhered to each other. , Table-shaped metal spacer 1
1 (21, 31) is assembled.

Hereinafter, this stack type semiconductor laser device 2 will be described.
00 will be described. First, the semiconductor laser chip 1 is die-bonded to a predetermined position on the upper surface of the heat sink 6.

Next, the semiconductor laser chips 2, 3, 3 are respectively placed at predetermined positions on the upper surfaces of the top plate portions 11a, 21a, 31a.
4 is die-bonded.

Next, after a plurality of (four) leg portions 11a are bonded to the upper surface of the heat sink 6 by using the insulating adhesive 8,
A top plate portion 11b, to which the semiconductor laser chip 2 is die-bonded, is adhered to the upper end surface of the leg portion 11a (here, the table-shaped spacer 11 is assembled).

Next, a plurality of (four) leg portions 21a are provided around the semiconductor laser chip 2 on the upper surface of the top plate portion 11b.
After standing, the top plate portion 21b having the semiconductor laser chip 3 die-bonded to the upper surface thereof is bonded to the upper end surfaces of the plurality of leg portions 21a (here, the table-shaped spacer 21 is assembled).

Next, a plurality (four) of leg portions 31a are provided around the semiconductor laser chip 3 on the upper surface of the top plate portion 21b.
After erected, the top plate portion 31b having the upper surface thereof die-bonded with the semiconductor laser chip 4 is bonded to the upper end surfaces of the plurality of leg portions 31a (here, the table-shaped spacers 31 are assembled).

Next, after wires 5a to 5d made of gold or the like are wire-bonded to the respective upper surface electrodes of the semiconductor laser chips 1 to 4, the wire 5a wire-bonded to the upper surface electrodes of the semiconductor laser chip 1 is mounted on the top plate portion 11b. Is electrically connected to the top electrode 21b of the semiconductor laser chip 2, and the wire 5b wire-bonded to the top electrode of the semiconductor laser chip 2 is electrically connected to the top plate 21b. Electrically connect to.

Finally, the wire 5d wire-bonded to the upper surface electrode of the semiconductor laser chip 4 and the heat sink 6
Is connected to a power source, the stack type semiconductor laser device 200 shown in FIG. 2 is obtained.

In the above steps, wire bonding to the upper surface electrodes of the semiconductor laser chips 1 to 4 and metal plate members 11b, 21b and 31b of the wires 5a to 5c are performed.
Was electrically connected to all the semiconductor laser chips 1 to 4 after die-bonding, but after the semiconductor laser chips were die-bonded, every time a metal plate member was provided above the semiconductor laser chip 1. The wire bonding to the upper surface electrode of the semiconductor laser chip and the electrical connection of the wire to the metal plate member may be performed.

In this embodiment as described above, the same effects as those of the above-described Embodiment 1 can be obtained, and the leg portions (the edge rod members 11a, 21a, 31a) can have a sufficient thickness, so that the stability and mechanical strength of these table-shaped spacer members 11, 21, 31 are improved, and the stack type semiconductor laser device 100 of the first embodiment is improved.
Highly reliable stack type semiconductor laser device 2
00 can be obtained.

In the above embodiment, the top plates 11b, 2b
After the semiconductor laser chips 2 to 4 are die-bonded to the upper surfaces of 1b and 31b, respectively, the table-shaped spacers 11, 21 and 31) are assembled on the heat sink.
1, 31) are assembled, and the top plate portion 11b (21b, 3) thereof is assembled.
1b) is die-bonded to the upper surface of the semiconductor laser chip 2 (3, 4) to assemble the above-mentioned stack elements 50a to 50c (of the first embodiment), and then these stack elements 50a to 50c are formed in the first embodiment. Similar effects can be obtained by stacking in the same manner as above.

Further, in the above-mentioned Embodiments 1 and 2, the top plate portion of the table-shaped spacer is formed into a quadrangle, but even if this is made into a different shape, a pattern for specifying the position where the chip is to be die-bonded is formed on the upper surface thereof. If formed, the same effects as those of the first and second embodiments can be obtained.

Example 3 3 is a front view showing the structure of a stack type semiconductor laser device according to a third embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and 60a to 60c are stacking elements. These are plate-shaped metal spacers 12, 13, 14 respectively.
And semiconductor laser chips 2, 3, which are die-bonded to the upper surfaces of the plate-shaped metal spacers 12, 13, 14.
It is composed of 4 and. Reference numeral 300 is a stack type semiconductor laser device. Here, the metal spacers 12, 13, 1
A pattern is drawn on the upper surface of the semiconductor laser chips 2, 3 and 4 to specify the positions on which the semiconductor laser chips 2, 3 and 4 are to be placed. , 3a, 4a are metal spacers 12, 1
It is positioned so as to be parallel to the front surface (front surface in the figure) of 3, 14. Also, the semiconductor laser chip 1
7a used for die bonding to the heat sink 6 and die bonding to the plate-shaped metal spacers 12 to 14 of the semiconductor laser chips 2 to 4, and the semiconductor laser below the stacking elements 60a to 60c. The melting point of the solder 7b is different from that of the solder 7b used for die bonding to the upper surface electrodes of the chips (1 to 3), and the solder 7b has a melting point lower than that of the solder 7a.
The wire 5 die-bonded to the upper surface electrode of the semiconductor laser chip 4 has one end (not shown) connected to a power supply (not shown), and the heat sink 6 is connected to the power supply (not shown) by wiring not shown. . In this figure, the upper surface electrodes and the lower surface electrodes of the semiconductor laser chips 1 to 4 are not shown.

Hereinafter, this stack type semiconductor laser device 3 will be described.
The assembly process of 00 will be described. According to this pattern, the semiconductor laser chip 2 is die-bonded onto the upper surface of the plate-shaped metal spacer 12 on which a pattern for specifying the position where the semiconductor laser chip 2 is to be mounted is drawn, according to this pattern. Then, the stacking element 60a in which the light emitting surface 2c of the semiconductor laser chip 2 is parallel to the front surface of the metal spacer 12 is assembled. And in the same way,
The stacking elements 60b and 60c are assembled.

Next, after the semiconductor laser chip 1 is die-bonded at a predetermined position on the upper surface of the heat sink 6 by using the solder 7a, the stacking element 60a is attached to the upper surface electrode of the semiconductor laser chip 1 and the metal spacer 12 thereof. Die bonding is performed using solder 7b so that the front surface of the metal spacer 12 is parallel to the light emitting surface 1a of the semiconductor laser chip 1 with the lower surface as an adhesive surface.
The stack element 60b is die-bonded to the upper surface electrode of the semiconductor laser chip 2 of the stack element 60a using the solder 7b with the lower surface of the metal spacer 13 as an adhesive surface, and the stack element 60b 6
0b of the semiconductor laser chip 3 is die-bonded to the upper surface electrode of the semiconductor laser chip 3 using the solder 7b with the lower surface of the metal spacer 14 as an adhesive surface. Here, the stacking elements 60a, 60b, 60c
Are the metal spacers 12, 1 that constitute them.
The side surfaces of each of 3 and 14 are sequentially stacked in a state of being along the flat surface of another member (not shown) and die-bonded. Thereby, the stacking elements 60a, 60b,
The semiconductor laser chips 2 to 60c are die-bonded to the upper surfaces of the metallic spacers 12, 13 and 14 of the metallic spacers 12, 13 and 14 so that their light emitting surfaces (2a, 3a, 4a) face a predetermined direction.
4 are arranged so that the light emitting surfaces 2a, 3a, 4a of each other face the same direction. Further, since the solder 7b used for die-bonding the stacking elements 60a, 60b, 60c has a melting point lower than that of the solder 7a used for die-bonding the semiconductor laser chips 1 to 4, these stacking elements are used. 60a, 60b,
The semiconductor laser chip 1 at the time of die bonding of 60c
Between the heat sink 6 and the semiconductor laser chips 2 to 4
The solder 7a interposed between the metal spacers 12 and 14 does not melt, and as a result, the semiconductor laser chips 1 to 4 are stacked with their light emitting surfaces 1a, 2a, 3a and 4a oriented in the same direction. . As described above, also in the present embodiment, the semiconductor laser chips 1 to 4 can be stacked so that their light emission surfaces face the same direction (so that the laser light emits in the same direction), and a predetermined high level is achieved. It is possible to obtain the stack type semiconductor laser device 300 capable of obtaining the optical output of power with good reproducibility. Further, in this stack type semiconductor laser device 300, the semiconductor laser chip 1 is dissipated by the heat sink 6 and the semiconductor laser chips 2-4 are dissipated by the metal spacers 12-14, so that performance deterioration due to temperature rise is not caused. Absent. However, in this embodiment, since the solder 7b is laid on the upper surface electrodes of the chips (1 to 3), the solder contacts the active layer exposed on the side surface of the chips (1 to 3), or the chips ( The conventional problem that stress is applied to the light emitting regions (1d to 3d) of 1 to 3) cannot be solved.

Example 4 4 is a side view showing the structure of a stack type semiconductor laser device according to Example 4 of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and 400 denotes a stack type semiconductor laser device.
This is composed of a heat sink 6a having a stepped surface, and semiconductor laser chips 1 to 4 die-bonded to each step of the stepped surface of the heat sink 6a. In the figure, 1e, 2e, 3e, and 4e represent laser beams emitted from the semiconductor laser chips 1 to 4, respectively. Although the upper surface electrodes and the lower surface electrodes of the semiconductor laser chips 1 to 4 are not shown in this figure, these lower surface electrodes are soldered to the stepped surface of the heat sink 6a by the solder 7, and A wire (not shown) made of gold or the like, one end of which is connected to a power source (not shown), is wire-bonded. The heat sink 6a is connected to the power source (not shown) by wiring not shown.

This stack type semiconductor laser device 400
The semiconductor laser chips 1 to 4 are arranged on each step of the stepped surface of the heat sink 6a, and the light emitting surfaces 1d, 2d,
After die bonding so that 3d and 4d face the same direction, wires are bonded to the upper surface electrodes of the chips 1 to 4 to assemble.

The stack type semiconductor laser device 400 assembled in this manner includes the semiconductor laser chips 1 to 1.
4 emits the laser beams 1e, 2e, 3e, 4e in the same direction and is radiated by the heat sink 6a, and the active layer exposed on the side surface thereof is not contacted by solder and electrically short-circuited. The predetermined laser light is emitted stably. Therefore, also in the present embodiment, similarly to the first and second embodiments, each of the chips 1 to 4 operates stably for a long period of time, and a predetermined high power optical output can be stably output for a long period of time. The laser device 400 can be obtained with good reproducibility.

[0061]

As described above, the present invention (claim 1,
According to 2), a plurality of table-shaped metal spacers are stacked on the upper surface of the heat sink,
Since the semiconductor laser chip is die-bonded to the upper surface of the top plate portion of each of the plurality of table-shaped metal spacers to assemble the stack type semiconductor laser device, each chip is accurately positioned on these upper surfaces. It is possible to stack a plurality of semiconductor laser chips so that the light emitting surfaces of the chips are surely oriented in the same direction. Further, since solder is not laid on the upper surface electrode of each chip, the active layer exposed on the side surface of each chip does not come into contact with each other, and stress is not applied to the light emitting region (active layer). The semiconductor laser chips can be stacked. Therefore, there is an effect that a plurality of stacked semiconductor laser chips operate stably for a long period of time, and a stack type semiconductor laser capable of stably outputting a predetermined high power optical output for a long period of time can be obtained with good reproducibility.

Further, according to the present invention (claims 3 and 4), the table-shaped metal spacer is obtained by bonding the top plate portion and the leg portion, which are separate from each other, to each other. Therefore, it is possible to make the leg portion thick enough to obtain sufficient strength, and as a result, the stacked semiconductor laser chips operate stably for a long period of time to provide a predetermined high power optical output. The stack type semiconductor laser capable of stable output for a long period of time has an effect of having excellent mechanical strength.

Further, according to the present invention (claims 5 and 6), there is provided a stacking element in which one semiconductor laser chip is die-bonded onto one plate-shaped metal spacer using the first solder. A plurality of stacking elements are sequentially stacked on the upper surface electrode of the semiconductor laser chip die-bonded to the upper surface of the heat sink using the first solder, and the upper and lower elements are connected to each other by the first solder. Since the stack type semiconductor laser device is assembled by die bonding using the second solder having a melting point lower than the melting point, the plurality of stacking elements are formed on the side surface of each of the one metal spacers. Along the flat surface of the other member and sequentially stacked so that a predetermined upper surface of the one metal spacer of the plurality of stacking elements is formed. The light emitting surface of the one semiconductor laser chip positioned in the stationary position can be arranged so as to surely face the same direction, and as a result, a stack type semiconductor capable of outputting a predetermined high power optical output. There is an effect that a laser can be obtained with good reproducibility.

Further, according to the present invention (claims 7 and 8), a plurality of semiconductor laser chips are formed by die-bonding a semiconductor laser chip to each step of the stepped surface of the heat sink having the stepped surface. Since the stack type semiconductor laser device is assembled without directly stacking the chips, a plurality of semiconductor laser chips can be stacked so that the light emitting surfaces of the chips are surely oriented in the same direction. Further, since solder is not laid on the upper surface electrode of each chip, the active layer exposed on the side surface of each chip does not come into contact with each other, and stress is not applied to the light emitting region (active layer). The semiconductor laser chips can be stacked. Therefore, there is an effect that a plurality of stacked semiconductor laser chips operate stably for a long period of time, and a stack type semiconductor laser capable of stably outputting a predetermined high power optical output for a long period of time can be obtained with good reproducibility.

[Brief description of drawings]

FIG. 1 is a front view showing the structure of a stack type semiconductor laser device according to a first embodiment of the present invention (FIG. 1 (a)) and an exploded perspective view showing the structure of a stacking element forming the stack type semiconductor laser device. Is.

FIG. 2 is a front view showing the structure of a stack type semiconductor laser device according to a second embodiment of the present invention.

FIG. 3 is a front view showing a structure of a stack type semiconductor laser device according to a third embodiment of the present invention.

FIG. 4 is a front view showing the structure of a stack type semiconductor laser device according to a fourth embodiment of the present invention.

FIG. 5 is a front view showing a structure of a conventional stack type semiconductor laser device.

6 is a top view (FIG. 6 (a)) and a side view (FIG. 6) for explaining the problems of the conventional stack type semiconductor laser device.
(b)).

[Explanation of symbols]

1-4 semiconductor laser chips 1a, 2a, 3a, 4a
Top electrode, 1b, 2b, 3b, 4b Bottom electrode, 1
c, 2c, 3c, 4c Light emitting surface 1d, 2d, 3d,
4d light emitting region (active layer), 1e, 2e, 3e, 4e
Laser light, 5,5a to 5d wire, 6,6a heat sink, 7,7a, 7b solder, 8 insulating adhesive, 1
0,11,20,21,30,31 Table-shaped metal spacers, 11a, 21a, 31a Legs, 11
b, 21b, 31b Top plate portion, 50a to 50c, 60a
~ 60c stacking device, 100, 200, 300,
400, 1000 Stack type semiconductor laser device.

Claims (8)

[Claims] 1. A step of die-bonding a semiconductor laser chip to an upper surface of a heat sink, and one semiconductor laser chip, an upper surface of a top plate portion of a table-shaped metal spacer including a top plate portion and a leg portion. A step of obtaining a plurality of stack elements formed by die-bonding to, on the upper surface of the heat sink, after fixing the leg portion of one stack element of the plurality of stack elements via an insulating layer, On the upper surface of the top plate portion of the one stacking element, other stacking elements different from the one stacking element of the plurality of stacking elements,
A step of stacking the plurality of stacking elements by fixing the leg portion arranged on the upper side to the upper surface of the top plate portion arranged on the lower side through an insulating layer, A stack type semiconductor laser device, comprising: a semiconductor laser chip die-bonded to an upper surface; and a stack type semiconductor laser device formed by stacking a plurality of semiconductor laser chips forming each of the plurality of stacking elements. Assembly method. 2. A heat sink having a semiconductor laser chip die-bonded to its upper surface, and one semiconductor laser chip, and an upper surface of the top plate portion of a table-shaped metal spacer having a top plate portion and legs. A plurality of stacking elements formed by die-bonding to the heat sink, the leg of one stacking element of the plurality of stacking elements is fixed to the upper surface of the heat sink via an insulating layer, and the one A plurality of stacking elements different from the one stacking element of the plurality of stacking elements on the upper surface of the top plate portion of the stacking element of Of the semiconductor laser stacked on the upper surface of the heat sink through an insulating layer and then die-bonded to the upper surface of the heat sink. Laser chip, and a plurality of semiconductor laser chips constituting each of the plurality of stacking elements are stacked to form a stack type semiconductor laser device. 3. The method for assembling a stack type semiconductor laser device according to claim 1, wherein the table-shaped metal spacer is obtained by bonding the top plate portion and the leg portion which are separate bodies from each other. A method for assembling a stack type semiconductor laser device characterized by the above. 4. The stack type semiconductor laser device according to claim 2, wherein the table-shaped metal spacer is obtained by bonding the top plate portion and the leg portion which are separate bodies to each other. A stack type semiconductor laser device characterized in that 5. A step of die-bonding a semiconductor laser chip on the upper surface of a heat sink using the first solder, and one semiconductor laser chip using the first solder on the upper surface of a plate-shaped metal spacer. And a step of obtaining a stack element formed by die bonding, and a plurality of the stack elements are bonded to the upper surface electrode of the semiconductor laser chip die-bonded to the upper surface of the heat sink by bonding the lower surface of the metal spacer to the bonding surface. A step of sequentially performing die-bonding using a second solder having a melting point lower than that of the first solder and stacking the second solder, the plurality of semiconductor laser chips constituting each of the plurality of stacking elements. Assembly of stack type semiconductor laser device characterized by assembling stack type semiconductor laser device Method. 6. A semiconductor laser chip die-bonded on the upper surface of a heat sink using the first solder, and one semiconductor laser chip on the upper surface of one plate-shaped metal spacer using the first solder. A plurality of stack elements formed by die-bonding, wherein the plurality of stack elements adhere the lower surface of the metal spacer to the upper surface electrode of the semiconductor laser chip die-bonded to the upper surface of the heat sink. The semiconductor laser chip and the plurality of stacks, which are sequentially die-bonded and stacked on the surface by using a second solder having a melting point lower than that of the first solder, and die-bonded on the upper surface of the heat sink. A plurality of semiconductor laser chips constituting each of the devices for use in a stack are stacked. Semiconductor laser device. 7. A stack type semiconductor laser device comprising a step of die-bonding a semiconductor laser chip to each step of the stepped surface of a heat sink having a stepped surface, wherein a stack type semiconductor laser device is formed by stacking a plurality of semiconductor laser chips. A method for assembling a stack type semiconductor laser device, which comprises assembling. 8. A stack type in which a semiconductor laser chip is die-bonded to each step of the stepped surface of a heat sink having a stepped surface, and a plurality of semiconductor laser chips are stacked. Semiconductor laser device.