JPH11163467A - Semiconductor device, its manufacturing method, and heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device, its manufacturing method, and a heat sink wherein a deflected laser bar is planarized, without being damaged by jointing it to a heat sink. SOLUTION: Through the use of a copper 3 with high coefficient of thermal expansion and a tungsten 2 with low coefficient of thermal expansion, a heat sink 1 is constituted with a laminate of different coefficients of thermal expansion, with the heat sink 1 being allocated over and under a deflected semiconductor device main body 5 for die bonding. Thus, the heat sink 1 is jointed in deflection similar to a semiconductor element main body 5 under heating at die bonding, and after being cooled down, the semiconductor element main body 5 is corrected to be flat accompanying the restoration in shape of the heat sink 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a semiconductor element in which a semiconductor element main body curved to one surface side and a heat sink are joined, and in this state, the semiconductor element main body has a straightened curve, and its manufacture. The present invention relates to a method and a heat sink used for the semiconductor device.

[0002]

2. Description of the Related Art A semiconductor laser is used as a light source for emitting light of a wavelength having a uniform phase, for reading recorded signals from a compact disk, a video disk or the like, and also for various uses. Such a semiconductor laser is, for example, GaAs
Although formed on a s (gallium, arsenic) substrate by a predetermined process, a plurality of materials having different compositions (for example, AlGaAs) are formed on a GaAs substrate to form the laser structure.
(Aluminum, gallium, arsenic) and GaAs) are grown in a stacked state.

That is, a plurality of AlGaAs clad layers and the like are stacked on a GaAs substrate with an active layer made of GaAs interposed therebetween by crystal growth. For example, a PN junction is formed on both surfaces of an active layer, and a laser beam is induced and emitted by injection type electroluminescence using the PN junction, and a guide type and a gain guide type having a known refractive index are known. .

FIGS. 4 to 12 show the steps of manufacturing such a semiconductor laser.

FIG. 4 shows an element forming surface 1 of a wafer 10A in a state where unnecessary portions on the outer periphery of the wafer (GaAs substrate) are removed.
0a shows a state in which the above-described crystal growth of each layer and formation of the upper electrode (however, these are not shown here) are performed.

Next, the wafer 10A is placed on the element forming surface 1
The surface on the opposite side of Oa is polished to form a total thickness t of about 100 μm as shown in FIG. In this state, a lower electrode is formed on the back surface 10b of the wafer.

Then, as shown in FIG. 6, a scribe line 1 having a predetermined width is formed along the cleavage surface by using a diamond cutter.
Insert 1.

Next, as shown in FIG. 7, the scribed wafer 10A is placed on a sponge-like mat 13, for example.
For example, by pressing the roller 12 while rolling it from above the wafer 10A, the wafer 10A is easily divided along the cleavage plane, and a large number of laser bars 14 are manufactured.

FIG. 8 is a perspective view showing the divided laser bar 14. As shown in FIG. 9, which is an enlarged schematic view of the laser bar, a lower electrode (common electrode) 22 made of metal is provided on the back surface. On a substrate 10 made of n-GaAs, a clat layer 16 made of n-type AlGaAs and an n-type G
An active layer 17 made of aAs and a clad layer 18 made of p-type AlGaAs are formed in a convex shape at the center and laminated, and a current confinement layer 20 made of n-type GaAs and a convex part are formed on both sides of the protrusion of the clad layer 18. A contact layer 21 made of p-type GaAs and an upper electrode 23 made of a metal are stacked on top of each other, and a laser emitting portion 19 is formed at the center of the active layer 17 on the cleavage surface 24.

When such an element body is used as a semiconductor array laser, the laser bar 1 shown in FIG.
4 is used, but when used as a semiconductor chip, the chip 15 is further divided from the state of the laser bar 14 as shown in FIG. In FIG. 9, a boundary 27 indicated by a virtual line indicates a cutting position when cutting as the chip 15.

The laser bar 14 thus formed is
Alternatively, the temperature of the chip 15 at the time of crystal growth is considerably higher than the normal temperature (for example, 800 ° C.), and lattice matching can be achieved at this temperature. Coefficient of thermal expansion due to the strain between layers formed with different compositions
The GaAs layer side 14b extends, and the GaAs substrate side 1
It warps to 4a.

FIG. 11 is a schematic view showing the laser bar 14 in such a state that it is warped and curved.
It may be several μm to several tens μm.

[0013]

However, in a semiconductor array laser, a fiber array, a lens array,
Alternatively, when light is condensed by a fiber lens, a cylindrical lens, or the like, it is preferable that the light emitting points are arranged in a straight line and flat, but such a warp causes deterioration of light condensing characteristics.

Therefore, as shown in FIG. 12, when the laser bar 14 is mounted (die-bonded) on the heat sink 25 by soldering or the like, the laser bar 14 is heated at a temperature (H) of about 250 ° C.
A pressure (P) is applied to the laser bar 14 by the pressing plate 26 to mount the die (die bond) while correcting the warpage.
After that, a method of waiting until the solder hardens by cooling may be adopted.

However, according to this method, the curved laser bar 14 is pressed against the flat heat sink 25,
The load becomes non-uniform, so that the convex central part of the laser bar 14 is buried in the solder, the thickness of the solder layer becomes non-uniform at the central part and the end part of the laser bar 14, or the load is not uniform. Problems such as damage to the laser bar 14 due to the uniformity occur.

The present invention has been made in view of the above circumstances, and always applies a uniform load between the heat sink and the element body during the bonding process between the element body such as a curved laser bar and the heat sink. In the state where the bonding material layer is formed to a uniform thickness, the previously curved element body is flattened, whereby the optical coupling with an optical component such as a lens array or a fiber array becomes accurate and easy. It is an object of the present invention to provide a semiconductor element capable of improving characteristics and reliability when used as a laser, a method for manufacturing the same, and a heat sink.

[0017]

Means for Solving the Problems The present inventor has conducted intensive studies to solve the above-mentioned objects, and as a result, has found an effective solution, and has reached the present invention.

That is, according to the present invention, in a semiconductor device in which a semiconductor element body curved to one surface side and a heat sink are joined, and in this joined state, the curvature of the semiconductor element body is corrected, the heat sink is thermally expanded. A semiconductor device according to the present invention, comprising a plurality of material layers having different rates, wherein the correction of the semiconductor device body is performed by a shape change of the heat sink according to a temperature change.

According to the semiconductor element of the present invention, a heat sink is constituted by a plurality of material layers having different coefficients of thermal expansion.
Since the shape change of the heat sink according to the temperature change is utilized, the heat sink and the semiconductor element body are not subjected to a load such as being subjected to uneven pressure at the time of straightening, and the semiconductor element is not changed according to the shape change according to the temperature change of the heat sink. The body is straightened. As a result, the bonding material layer is formed to a uniform thickness by the uniform load, the flatness is good, the optical coupling with the lens array or the fiber array is particularly accurate and easy, and the heat sink by the heat sink is sufficient. An element can be provided.

The present invention also relates to a method of manufacturing a semiconductor device in which a semiconductor element body curved to one surface side and a heat sink are joined, and in this joined state, the curvature of the semiconductor element body is corrected. Comprising a plurality of material layers having different coefficients of thermal expansion, and changing the shape of the heat sink with a change in temperature during the bonding, thereby performing the correction of the semiconductor element body. (Hereinafter, referred to as a manufacturing method of the present invention).

According to the manufacturing method of the present invention, the heat sink is composed of a plurality of material layers having different coefficients of thermal expansion, and the shape of the heat sink changes with the temperature change when the heat sink and the semiconductor element are joined. So, for example, a flat heat sink at normal temperature is bent and bonded at the same curvature as the semiconductor element body that is curved at the time of die bonding, and the semiconductor element body is corrected by the heat sink that recovers flat with cooling, and during the die bonding process. Thus, the bonding material layer is formed to have a uniform thickness, so that the semiconductor element body can be prevented from being damaged.

Further, the present invention provides a heat sink which is joined to a semiconductor element body curved to one surface side, and in this joined state, corrects the curvature of the semiconductor element body.
The present invention relates to a heat sink comprising a plurality of material layers having different coefficients of thermal expansion, wherein the correction of the semiconductor element body is performed by a shape change with a temperature change.

According to the heat sink of the present invention, since the heat sink is configured based on the above-described manufacturing method, a good heat sink for manufacturing the above-described semiconductor element can be provided.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the above-described semiconductor device, manufacturing method, and heat sink according to the present invention, the heat sink has a property of being curved in the same shape as the semiconductor device main body when the temperature is raised, and restoring to its original shape when cooling. It is desirable.

The heat sink is joined to at least one surface of the semiconductor element body, and the heat sink is joined to a curved convex surface of the semiconductor element body on the side of the material layer having a small coefficient of thermal expansion. It is desirable.

However, the heat sink may be joined to the curved concave surface of the semiconductor element body on the side of the material layer having a high coefficient of thermal expansion.

One of the heat sinks is joined to the curved convex surface of the semiconductor element body on the side of the material layer having a low coefficient of thermal expansion, and the other heat sink is connected to the semiconductor element body on the side of the material layer having a large coefficient of thermal expansion. It may be configured to be joined to the concave surface when curved.

In this case, the semiconductor element body may be a laser bar or a laser chip, and the heat sink may be joined to the surface on both sides of the laser emission surface.

Further, it is preferable that the heat sink is used as an electrode by configuring as described above.

Hereinafter, the semiconductor device and the manufacturing method of the present invention,
Preferred embodiments of the heat sink will be specifically described with reference to the drawings.

FIG. 1 shows a first embodiment. The semiconductor element (for example, a semiconductor laser array element) of the present embodiment uses a heat sink composed of two or more material layers having different coefficients of thermal expansion.
This is to correct the curvature of the laser bar 14 (or the chip 15) of the semiconductor laser as described above.

That is, if the heat sink is curved in the same state as the laser bar in the high temperature state at the time of die bonding, and is flat at normal temperature, the heat sink and the laser bar can always have the same curvature during the die bonding process, and can be uniformly formed. Weighting can be applied.

In the case of a semiconductor laser, as described above, the substrate material is GaAs, and GaAs is
Al _x Ga containing a fixed amount of Al (aluminum) in s
There are a plurality of _1-x As (for example, x is about 0.1 to 0.6) layers. The thermal expansion coefficient of GaAs is 6.5 × 10 ⁻⁶ /
° C and Al _x Ga _{1 -x} As depending on the mixed crystal ratio x of Al.
Has a coefficient of thermal expansion of 6.5 × 10 ⁻⁶ / ° C.

As described above, the materials having different compositions of thermal expansion are crystal-grown at a high temperature (for example, 800 ° C.).
As shown in FIG. 1A, when the laser bar 5 is cooled to room temperature, interlayer distortion occurs (the laser bar 5 is provided with the above-described upper and lower electrodes).
Therefore, as shown in FIG. 1A, the heat sink 1 is made of a material having a low coefficient of thermal expansion (hereinafter, referred to as a low expansion material) 2 and
A material having a high coefficient of thermal expansion (hereinafter, referred to as a high-expansion material) 3.

For example, the mixed crystal ratio x of Al is 0.5 on average.
Then, the coefficient of thermal expansion of Al _x Ga _{1 -x} As is 5.9 × 1
0 ⁻⁶ / ° C., and the thermal expansion coefficient of GaAs and the substrate.
The difference from 5 × 10 ⁻⁶ / ° C., ie 0.6 × 10 ⁻⁶ / ° C.,
If the heat sink 1 is made of a material having a different coefficient of thermal expansion between the high expansion material 3 and the low expansion material 2, the heat sink 1 will be curved in the same manner as the laser bar 5 during die bonding.

Therefore, in the present embodiment, the heat sink 1 configured as described above is disposed above and below the laser bar 5 as shown in FIG. That is, the upper heat sink 1 makes the high expansion material 3 contact the curved concave surface of the laser bar 5, and the lower heat sink 1 ′ makes the low expansion material 2 contact the curved convex surface of the laser bar 5. Solders 1 and 1 'are previously attached to the contact surfaces with the laser bar 5 by vapor deposition or the like.

Then, as shown in FIG. 1 (b), the heat sink 1 is placed on a surface plate 7 which can be heated by a heater or the like, and a weight (P) is applied to the upper heat sink 1 while heating (H). Since the upper and lower heat sinks 1 and 1 ′ are a laminate of the above-described high expansion material and low expansion material, they are curved in the same direction with the same curvature as the laser bar 5. Therefore, the heat sink 1
And the laser bar 5 are evenly contacted with each other, and the two are evenly weighted by the contact surface, and a solder layer (not shown: the same applies hereinafter)
2a and 3a can also be formed with a uniform thickness.

FIG. 1C shows a state in which the heat sink 1 is cooled to room temperature after bonding. As described above, the heat sink 1 is composed of the low expansion material 2 and the high expansion material 3 having different thermal expansion coefficients. During bonding, the heat sink 1 that has been curved as shown in FIG. 1B is restored to a flat shape with cooling, and the laser bar 5 joined thereto is also corrected to be flat. . Such correction of the laser bar 5 enables accurate and easy optical coupling with a lens array or a fiber array.

As materials that can be used for such a heat sink 1, copper and tungsten are suitable, but in addition, copper-molybdenum, aluminum-silicon-
And carbon.

In this embodiment, as shown in FIG. 9, heat sinks 1 and 1 'are vertically joined to a laser bar 5 provided with upper and lower electrodes, respectively. It can also be used. In particular, the upper heat sink 1 (substrate side) is wire-bonded in a subsequent step (in the case of FIG. 9, the individual electrodes 23 need to be wire-bonded to the power supply terminals).
Is unnecessary, or only one wire bond is required, so that the manufacturing process can be simplified and deterioration of the laser bar due to the wire bond can be avoided. However, the upper and lower electrodes as shown in FIG. 9 may not be provided in advance and may also serve as electrodes with a heat sink, and the present embodiment may be applied to a chip shown in FIG. The same applies to other embodiments).

The upper heat sink 1 has a remarkably large heat dissipation compared to the method of taking out electrodes by wire bonding or the like, and has a uniform contact with the laser bar 5 as compared with the wire bonding or the like. A current distribution can be obtained, and characteristics and reliability can be improved.

It is preferable that the heat sink and the laser bar are joined with a conductive joining material such as solder, but an insulating joining material can also be used. In this case, the heat sink need not necessarily be used as an electrode.

FIG. 2 shows a second embodiment. In the present embodiment, as shown in FIG. 2, the heat sink 1 ′ has the low expansion material 2 side in contact with the laser bar 5, and It may be provided only in the case. FIG. 2 (a) shows a state before joining, as in the case described above with reference to FIG.
Solder is vapor-deposited on the surface of the heat sink 1 'on the side of the low expansion material 2 in advance.

Next, as shown in FIG. 2 (b), the heat sink 1 'and the laser bar 5 are placed on a surface plate 7 which can be heated by a heater or the like while being heated. The plate spring 8 is pressed from above.
Thereby, the heat sink 1 'is curved in the same manner as the laser bar 5 on the same principle as in the case of FIG. 1 described above, and both are joined with equal pressure, and the solder layer can also be formed with a uniform thickness.

After this is cooled to room temperature, FIG.
As shown in (1), the laser bar 5 is corrected to a flat shape as the heat sink 1 'is restored to a flat state. Therefore, optical coupling with a lens array or a fiber array can be performed accurately and easily.

FIG. 3 shows the third embodiment. In this embodiment, the heat sink 1 may be provided only above the laser bar 5 as shown in FIG. In this case, solder is previously adhered to the surface of the heat sink 1 on the side of the high expansion material 3 by vapor deposition or the like, and the heat sink 1 is overlaid on the laser bar 5 as shown in FIG. While heating on the surface plate 7, the heat sink 1 is evenly loaded from above.

Thus, after cooling to room temperature, as shown in FIG. 3B, as the heat sink 1 is restored to a flat state, the laser bar 5 is also corrected to a flat shape. Therefore, also in this case, the same effects as those of the first embodiment can be obtained.

[0048]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments.

A semiconductor device was manufactured according to the above-described first preferred embodiment of the present invention. FIG. 1 is a schematic sectional view of a main part showing an outline of a semiconductor device of the present embodiment and a manufacturing process thereof. Note that the same reference numerals are used for the same parts as those in the above-described embodiment.

The heat sink 1 of this embodiment has a layer structure using copper 3 as a material having a high coefficient of thermal expansion and tungsten 2 as a material having a low coefficient of thermal expansion. Therefore, this heat sink 1 has high conductivity that can be used as an electrode as it is, and utilizes the difference in the coefficient of thermal expansion between the two, and the same ratio as the curvature of the laser bar 5 at the time of heating by the composition ratio of copper 3 and tungsten 2. A curvature can be formed.

As described above, the laser bar 5 has a thermal expansion coefficient of 6.5 × 10 ^-6 /
C. GaAs (gallium, arsenic) layer and a thermal expansion coefficient of 5.9 mixed with Al (aluminum) adjacent thereto.
The layer of Al _x Ga _1-x As of ^10-6 / ° C is, for example, 8
After the crystal is grown at a high temperature of 00 ° C., when the layer is cooled to room temperature, a distortion occurs between the layers and a curve is formed. When such a laser bar 5 and the heat sink 1 are die-bonded at a temperature lower than the above-mentioned crystal temperature (for example, 250 ° C.), copper 3 and tungsten 2 This can be dealt with by adjusting the composition ratio.

That is, the coefficient of thermal expansion of copper tungsten is changed from 6.5 × 10 ⁻⁶ / ° C. to 8.5 × 10 ⁻ by changing the ratio of copper 3 to tungsten 2 from 1: 9 to 2: 8. ⁶
/ ° C. This is because Ga
The thermal expansion coefficient of As is 6.5 × 10 ⁻⁶ / ° C. and Al _x Ga _{1 -x} A
This is a change in the coefficient of thermal expansion sufficient to give a difference of 0.6 × 10 ⁻⁶ / ° C. from the coefficient of thermal expansion of s.

However, as described above, the curvature of the laser bar 5 is actually 800 ° C. during crystal growth and room temperature (25 ° C.).
The temperature at the time of die bonding between the laser bar 5 and the heat sink 1 (for example, 250 ° C.)
In order to give the same curvature at a small temperature difference between room temperature and room temperature, a difference in thermal expansion coefficient of about 3.4 times is required. this is,
This corresponds to a difference in coefficient of thermal expansion of about 2.0 × 10 ⁻⁶ / ° C., and corresponds to a case where the composition ratio of copper 3 and tungsten 2 is changed from 1: 9 to 2: 8.

Accordingly, copper 3 and tungsten 2 as described above are used.
The heat sink 1 is constituted by the composition ratio of the above. Then, as shown in FIG. 1, the heat sink 1 configured as described above was arranged above and below the laser bar 5 and joined. The manufacturing process of the semiconductor element in which the heat sink 1 is arranged as described above is roughly as follows.

First, as shown in FIG. 1A, solder (not shown) is deposited on the lower surface 3a of the copper layer 3 of the upper heat sink 1 and the upper surface 2a of the tungsten layer 2 of the lower heat sink 1 'by vapor deposition or the like. The semiconductor laser bar 5 is sandwiched between them.

Then, as shown in FIG. 1 (b), the heater (not shown) is placed on a surface plate 7 having a built-in heater. Heat at (H) to melt the solder. As a result, at room temperature, the flat heat sink 1 is curved with the same curvature as the laser bar 5.

Since the heat sink 1 is made of a material having a difference in coefficient of thermal expansion as described above, the heat sink 1 is flat at room temperature, but also has the same curvature as the laser bar 5 at the time of die bonding. And the solder layer could be formed with a uniform thickness.

After joining the laser bar 5 and the heat sink,
Cool until the solder solidifies while applying weight. And
When the temperature reaches room temperature, as shown in FIG. 1C, the heat sink 1 is restored to a flat shape, and the laser bar 5 sandwiched between the heat sink 1 is also corrected to a flat shape.

According to the present embodiment, if the heat sink 1 is made of a material having a different coefficient of thermal expansion so as to form the same curvature as the curvature of the laser bar 5 at the time of die bonding, the flat heat sink 1 at room temperature becomes After cooling, the laser bar 5 as well as the heat sink 1 can be corrected to a flat shape after cooling.

Further, since the upper heat sink can be used as an electrode, wire bonding becomes unnecessary, so that laser deterioration due to wire bonding can be avoided and the manufacturing process can be simplified.

Further, the upper heat sink contributes to a much larger heat dissipation than the method of taking out the electrodes by wire bonding or the like, and more uniformly contacts the laser bar 5 than the wire bonding or the like. A high current distribution can be obtained, and characteristics and reliability can be improved.

[0062]

As described above, according to the present invention, there is provided a semiconductor device in which a semiconductor element body curved to one surface side and a heat sink are joined, and in this joined state, the curvature of the semiconductor element body is corrected. The heat sink is composed of a plurality of material layers having different coefficients of thermal expansion, and the correction of the semiconductor element body is performed by a shape change of the heat sink according to a temperature change. Without being affected, the semiconductor element body joined to the heat sink is naturally corrected following the shape change accompanying the temperature change of the heat sink. As a result, the bonding element layer for bonding is formed to a uniform thickness, and a semiconductor element with good flatness and sufficient heat dissipation by a heat sink is provided.In particular, accurate optical coupling with a lens array or a fiber array is provided. And can be easily performed.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a semiconductor device and a method of manufacturing the same according to the present invention, wherein (a) shows a step before bonding, (b) shows a die bonding step, and (c) shows a step after bonding.

FIG. 2 shows another example of a semiconductor device according to the present invention;
(A) is a state before joining, (b) is a state during die bonding,
(C) is a schematic sectional view showing a state after joining.

3A and 3B are schematic cross-sectional views showing still another example of the semiconductor element, in which FIG. 3A shows a state during die bonding, and FIG. 3B shows a state after bonding.

FIG. 4 is a schematic perspective view showing one manufacturing process of a semiconductor chip according to a conventional example.

FIG. 5 is a schematic perspective view showing another process.

FIG. 6 is a schematic perspective view showing another process of the same.

FIG. 7 is a schematic perspective view showing another process of the same.

FIG. 8 is a schematic perspective view showing still another process.

FIG. 9 is a schematic enlarged perspective view of the same laser bar.

FIG. 10 is a schematic perspective view of the cut laser chip.

FIG. 11 is a schematic view of the laser bar.

FIG. 12 is a schematic view showing a bonding method of the semiconductor element.

[Explanation of symbols]

1, 1 ': heat sink, 2: tungsten (low expansion material), 3: copper (high expansion material), 5, 14: laser bar, 7
... Surface plate, 8 leaf spring, 10 substrate (n-GaAs), 1
0A wafer, 10a element formation surface, 15 laser chip, 16 cladding layer (n-type GaAlAs), 17 active layer (n-type GaAs), 18 cladding layer (p-type GaAs)
lAs), 19: emission part, 20: current confinement layer (n-type Ga
As), 21 ... contact layer (p-type GaAs), 22 ...
Lower electrode, 23: upper electrode, H: heat, P: pressure

Claims (23)

[Claims] In a semiconductor device in which a semiconductor element body curved to one surface side and a heat sink are joined, and in this joined state, the semiconductor element body has a corrected curvature, the heat sink has a plurality of different thermal expansion coefficients. Wherein the correction of the semiconductor element body is performed by a shape change of the heat sink according to a temperature change. 2. The semiconductor device according to claim 1, wherein the heat sink has a property of being curved in the same shape as the semiconductor device main body when the temperature rises and restoring to its original shape when cooling. 3. The semiconductor device according to claim 1, wherein the heat sink is joined to at least one surface of the semiconductor device body. 4. The semiconductor device according to claim 3, wherein the heat sink is joined to a curved convex surface of the semiconductor device body on a side of a material layer having a small coefficient of thermal expansion. 5. The semiconductor device according to claim 3, wherein said heat sink is joined to a concave surface of said semiconductor device body when curved on a side of a material layer having a high coefficient of thermal expansion. 6. One of the heat sinks is joined to the curved convex surface of the semiconductor element body on the side of the material layer having a low coefficient of thermal expansion, and the other heat sink is connected to the semiconductor element body on the side of the material layer having a large coefficient of thermal expansion. The semiconductor device according to claim 3, wherein the semiconductor device is joined to the concave surface when the surface is curved. 7. The semiconductor device according to claim 1, wherein said semiconductor device main body is a laser bar or a laser chip, and said heat sink is joined to surfaces present on both sides of said laser emission surface. 8. The semiconductor device according to claim 7, wherein said heat sink is used as an electrode. 9. A method of manufacturing a semiconductor device in which a semiconductor element body curved to one surface side and a heat sink are joined, and in this joined state, the curvature of the semiconductor element body is corrected. Wherein the shape of the heat sink is changed in accordance with a change in temperature during the bonding, thereby performing the correction of the semiconductor element body. 10. The method of manufacturing a semiconductor device according to claim 9, wherein the heat sink is curved to have the same shape as the semiconductor device body when the temperature is raised, and is restored to an original shape when cooled. 11. The method according to claim 9, wherein the heat sink is joined to at least one surface of the semiconductor element body. 12. The method of manufacturing a semiconductor device according to claim 11, wherein the heat sink is joined to a curved convex surface of the semiconductor device body on a side of a material layer having a small coefficient of thermal expansion. 13. The method of manufacturing a semiconductor device according to claim 11, wherein the heat sink is joined to a concave surface of the semiconductor device main body at the side of the material layer having a large coefficient of thermal expansion. 14. One of the heat sinks is joined to the curved convex surface of the semiconductor element main body on the side of the material layer having a low coefficient of thermal expansion, and the other heat sink is connected to the semiconductor element main body on the side of the material layer having a large coefficient of thermal expansion The method of manufacturing a semiconductor device according to claim 11, wherein the semiconductor device is bonded to a concave surface when the semiconductor device is curved. 15. The method of manufacturing a semiconductor device according to claim 9, wherein the semiconductor device main body is a laser bar or a laser chip, and the heat sink is joined to surfaces present on both sides of the laser emission surface. 16. The method according to claim 15, wherein the heat sink is used as an electrode. 17. A heat sink, which is joined to a semiconductor element body curved to one surface side and in which the semiconductor element body is curved in this joined state, is constituted by a plurality of material layers having different coefficients of thermal expansion; A heat sink, wherein the correction of the semiconductor element body is performed by a shape change due to a temperature change. 18. The heat sink according to claim 17, wherein the heat sink has a property of being curved in the same shape as the semiconductor element main body at the time of raising the temperature and of returning to the original shape at the time of cooling. 19. The heat sink according to claim 17, wherein the heat sink is joined to at least one surface of the semiconductor element body. 20. The semiconductor element body is joined to a convex surface of the semiconductor element body when curved on a side of a material layer having a small coefficient of thermal expansion.
The heat sink described in. 21. The semiconductor element body is joined to a concave surface of the semiconductor element body when curved on a side of a material layer having a high thermal expansion coefficient.
The heat sink described in. 22. The heat sink according to claim 17, wherein the semiconductor element main body is a laser bar or a laser chip, and is bonded to surfaces present on both sides of the laser emission surface. 23. The heat sink according to claim 22, which is used as an electrode.