JP2002164606A - Semiconductor device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device and its manufacturing method wherein a plurality of semiconductor elements are mounted on a submount member horizontally and stable characteristic and high reliability can be obtained, when a plurality of the semiconductor elements formed on a semiconductor substrate are down-mounted on the submount member and height difference exists between the semiconductor elements. SOLUTION: A relatively high AlGaAs based infrared laser element 20, a relatively low AlGaInP based infrared laser element 30 and a protruding type retaining body 40 having a height nearly equal to that of the laser element 20 which are formed on an N-type GaAs substrate 10 are down-mounted on the submount member 50. The submount member 50 is interposed between a surface of the substrate 10 and an element mounting surface of the submount member 50. As a result, when the height difference exists between both the semiconductor laser elements, the substrate 10 is not inclined on account of the height difference and horizontal down-mounting is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly to a semiconductor device in which a plurality of semiconductor elements formed on a semiconductor substrate are mounted on a submount member and a method of manufacturing the same. It is.

[0002]

2. Description of the Related Art At present, the necessity of integration of optical devices is rapidly recognized. For example, integrated high-performance optical devices using a plurality of semiconductor laser elements having different oscillation wavelengths are used for consumer equipment. It is already on the market as a key device. As a method of manufacturing such an integrated high-performance optical device, a plurality of semiconductor laser elements having different oscillation wavelengths are separately manufactured, and one step is performed in the assembly process.
There is a method of combining a plurality of devices with one device, and a method of fabricating a plurality of semiconductor laser devices having different oscillation wavelengths on one substrate and forming the devices using a normal assembly process.

[0003] In these two manufacturing methods, the former manufacturing method not only requires approximately twice as many production steps as the latter manufacturing method, but also requires a semiconductor laser device which is most important as an integrated device. The alignment accuracy is inferior to the latter manufacturing method. Therefore, when the two are compared, the latter manufacturing method clearly has an advantage.

[0004]

When a group of semiconductor laser elements having different oscillation wavelengths is formed on one substrate, a plurality of semiconductor laser elements must be obtained in pursuit of an optimum laser structure for each oscillation wavelength. Are different from each other. However, even in that case, for example, in the case of a two-wavelength laser device exclusively for reading DVDs having output wavelengths of 780 nm and 650 nm, the optical output is about 3 to 5 mW, so the thickness of the cladding layer constituting the laser structure is 1 μm.
It is not necessary to increase the thickness to about m, and the difference between the heights of the two semiconductor laser devices from the surface of the semiconductor substrate, that is, the height difference between the two semiconductor laser devices is not so large.

However, for example, when the light output is 100 to 150 m
A high-power semiconductor laser device for writing a CD-R / RW of about W and a relatively low-output DVD read-only semiconductor laser device having a light output of about 3 to 5 mW are mounted on the same semiconductor substrate. In order to manufacture a two-wavelength laser device formed in the above, it is necessary to increase the thickness of the cladding layer sandwiching the active layer in order to enable high output of one of the semiconductor laser elements. There is a height difference that cannot be ignored between the elements.

For example, as shown in FIG.
On the As substrate 10, the output wavelength is 780 nm and the optical output is 1
AlGaAs-based infrared laser device 2 of 100 to 150 mW
0 and A with an output wavelength of 650 nm and an optical output of 3 to 5 mW
It is assumed that the 1GaInP-based infrared laser device 30 is formed.

Here, one AlGaAs infrared laser element 20 is composed of an n-AlGaAs cladding layer 21a, an active layer 22a,
The p-AlGaAs cladding layer 23a, the p-AlGa
A stripe ridge 27 composed of an etching stop layer 24a, a p-AlGaAs clad layer 25a, and a p-GaAs cap layer 26a, which are sequentially stacked on the As clad layer 23a, and n in which the stripe ridge 27 is embedded.
-AlGaAs buried layer 28a, these stripe ridges 27 and n-AlGaAs buried layer 28a
The active layer 22a is composed of a p-AlGaAs cladding layer 25a on and under the active layer 22a.
And p-AlGaAs cladding layer 23a and n-AlGa
It has a laser structure sandwiched between the As cladding layer 21a.

The other AlGaInP-based infrared laser element 30 also includes an n-AlGaInP cladding layer 31 a and an active layer 32 which are sequentially stacked on an n-GaAs substrate 10.
a, p-AlGaInP cladding layer 33a, p-GaAs
The active layer 32a is composed of an s cap layer 34a and a p-stripe surface electrode 35 formed on the p-GaAs cap layer 34a. A p-AlGaInP cladding layer 33a and an n-AlGaInP cladding layer 31a are formed above and below the active layer 32a.
To form a laser structure. Also, n
An n-substrate-side electrode 11 is formed on the back surface of the GaAs substrate 10.

The relatively high output Al
If the laser structures of the GaAs infrared laser element 20 and the AlGaInP infrared laser element 30 having a relatively low output are optimized respectively, the high output of the AlGaAs infrared laser element 20 is enabled. , AlGaAs
N-AlGaAs cladding layer 21a, p-AlGaAs cladding layer 23a, and p-A
The thickness of the lGaAs cladding layer 25a needs to be greater than the thickness of the n-AlGaInP cladding layer 31a or the p-AlGaInP cladding layer 33a of the AlGaInP-based infrared laser device 30. As a result, the height of the AlGaAs infrared laser device 20 from the surface of the n-GaAs substrate 10 (hereinafter simply referred to as “AlGaAs infrared laser device 2”).
0 height. " ) Is higher than the height of the AlGaInP-based infrared laser device 30 from the surface of the n-GaAs substrate 10 (hereinafter, simply referred to as “height of the AlGaInP-based infrared laser device 30”). A height difference h that cannot be ignored, for example, about 2 μm occurs between them.

When assembling the two-wavelength laser device shown in FIG. 12, as shown in FIG.
With the As substrate 10 inverted and the p-surface electrode 29 of the AlGaAs-based infrared laser device 20 and the p-striped surface electrode 35 of the AlGaInP-based infrared laser device 30 facing downward, the device of the submount base 51 is It must be mounted on the submount member 50 on which the pattern electrodes 52 and 53 made of In-Sn solder are formed on the mounting surface. Such a method of mounting the semiconductor device on the submount member with the surface electrode of the semiconductor device facing downward is generally called a downmount.

Then, when actual down-mounting is performed using a predetermined die bonding apparatus, the result is as shown in FIG. That is, p of the AlGaAs infrared laser device 20
The surface electrode 29 is joined to the pattern electrode 52 of the submount member 50, and the AlGaInP-based infrared laser device 3
0 p-stripe surface electrode 35 and submount member 5
The zero pattern electrode 53 is joined. At this time, the AlGaAs infrared laser element 20 and the AlGaI
Due to the height difference from the nP-based infrared laser element 30, the AlGa
The As-based infrared laser device 20 and the AlGaInP-based infrared laser device 30 are inclined, and the submount member 5
An inclination θ occurs with respect to the bottom surface of 0.

As a result, the light emitting points of the AlGaAs infrared laser element 20 and the AlGaInP infrared laser element 30 are displaced, the distance between the light emitting points is shortened, and the optical axis shifts to cause an optical pickup. However, there is a problem that optical system alignment becomes difficult.

Further, during down-mounting using a die bonding apparatus, pressure is applied to the AlGaAs infrared laser element 20 and the AlGaInP infrared laser element 30 in an oblique direction.
The s-based infrared laser device 20 and the AlGaInP-based infrared laser device 30 are distorted, causing a problem that the polarization angle at the time of light emission varies and causes poor characteristics.

As a method for solving such a problem, for example, the thickness of the p-surface electrode 29 of the AlGaAs infrared laser device 20 having a relatively high height is reduced by changing the thickness of the AlGaInP having a relatively low height. -Of the infrared laser element 30
It is conceivable that the thickness is made sufficiently larger than the thickness of the stripe surface electrode 35 so that the heights of the two semiconductor laser elements are effectively equal. However, in this case, AlGaAs
In general, the p-surface electrode 29 of the
Since u is used as a material and is formed by a vapor deposition method, it results in an increase in cost due to an increase in the amount of expensive raw materials used and a decrease in productivity in terms of lead time, which is not preferable.

Another solution is to use AlGaAs.
A relatively thin solder layer is interposed between the p-surface electrode 29 of the infrared laser device 20 and the pattern electrode 52 of the submount member 50, and the p-electrode of the AlGaInP infrared laser device 30 is formed. A method has been proposed in which a relatively thick solder layer is interposed between the stripe surface electrode 35 and the pattern electrode 53 of the submount member 50 to eliminate the difference in height between the two semiconductor laser elements (Japanese Patent Laid-Open No. H10-163,837). 7-23
No. 5729). However, in this case, when the molten solder layer is cooled and solidified during down mounting,
For example, when alloying with the p-surface electrode 29 and the p-stripe surface electrode 35 made of Au, the progress is not always uniform in each part, so that a variation occurs in volume change and the like, and the AlGaAs infrared laser element 20 And Al
It becomes difficult to accurately maintain the state in which the GaInP-based infrared laser element 30 is horizontally mounted on the sub-mount member 50, and eventually, a tilt occurs.

The present invention has been made in view of the above circumstances, and has been made in consideration of the above circumstances. In the case where a plurality of semiconductor elements formed on a semiconductor substrate are down-mounted on a submount member, a plurality of semiconductor elements are provided. It is an object of the present invention to provide a semiconductor device in which a plurality of semiconductor elements are horizontally mounted on a submount member even if there is a height difference therebetween, and stable characteristics and high reliability can be obtained, and a method for manufacturing the same.

[0017]

The above objects can be attained by a semiconductor device and a method of manufacturing the same according to the present invention described below. That is, in the semiconductor device according to the first aspect, a plurality of semiconductor elements formed on a semiconductor substrate have a plurality of semiconductor elements corresponding to each surface electrode, with each surface electrode of the plurality of semiconductor elements facing downward. A semiconductor device mounted on a submount member having a pattern electrode, wherein a projecting support formed on the semiconductor substrate is interposed between a semiconductor substrate surface and an element mounting surface of the submount member. The convex-shaped support has a height substantially equal to the height of the tallest semiconductor element among the plurality of semiconductor elements. Here, the “height” of the convex support or the plurality of semiconductor elements means the height from the surface of the semiconductor substrate.

In the semiconductor device according to the first aspect of the present invention, when the plurality of semiconductor elements formed on the semiconductor substrate are mounted on the submount member, the surface of the semiconductor substrate and the element on the submount member are mounted. Between the mounting surface, a convex-shaped support formed on the semiconductor substrate is interposed, and the convex-shaped support is formed of a plurality of semiconductor elements formed on the semiconductor substrate. Since the semiconductor device has the same height as the tallest semiconductor device, even if the height of the plurality of semiconductor devices is different and there is a height difference between the plurality of semiconductor devices, the semiconductor substrate and the The mounting member is substantially parallel to the mounting member, and the plurality of semiconductor elements are horizontally down-mounted on the sub-mounting member. For this reason,
It is possible to prevent the plurality of semiconductor elements mounted on the sub-mount member from being tilted due to the height difference between the plurality of semiconductor elements, thereby preventing the assembly position accuracy of the semiconductor device from being reduced.

Further, when a plurality of semiconductor elements formed on the semiconductor substrate are down-mounted on the submount member, no oblique pressure is applied to each of the semiconductor elements, so that each semiconductor element is distorted. It is also possible to prevent the occurrence of a defective characteristic.

In general, a substrate-side electrode is formed on the back surface of the semiconductor substrate, and the substrate-side electrode surface is exposed upward with down-mounting. Since it is parallel to the bottom surface of the member, wire bonding on the lower electrode surface can be easily and accurately performed.

Further, in order to mount the plurality of semiconductor elements horizontally on the submount member, a plurality of semiconductor elements may be provided with surface electrodes having different thicknesses, Compared with the conventional case in which a solder layer having a different thickness is interposed between the member and the pattern electrode, a rise in cost due to an increase in the electrode material and a decrease in productivity due to complicated processes are prevented.

In the semiconductor device according to claim 1, at least one of the plurality of semiconductor elements is preferably a semiconductor light emitting element (claim 2). That is, in the case of a semiconductor light emitting device, the accuracy of the assembling position strongly affects the characteristics, so that the effect of the present invention is more effectively exhibited.

For example, a plurality of semiconductor light emitting devices are mounted horizontally on a submount member, and the plurality of semiconductor light emitting devices are inclined due to a difference in height between the plurality of semiconductor light emitting devices. If the situation where the assembling position accuracy is reduced is prevented, a situation in which the optical axis is displaced due to the displacement of the light emitting point and, consequently, a characteristic failure such as a poor optical system alignment is prevented. Further, when a plurality of semiconductor light emitting devices formed on the semiconductor substrate are down-mounted on the sub-mount member, no oblique pressure is applied to each semiconductor light emitting device, and each semiconductor light emitting device is distorted. When it disappears, it is also possible to prevent the polarization angle from being varied or causing a defect during light emission.

In addition, at least one of the plurality of semiconductor elements
When each of the semiconductor light emitting devices is a semiconductor light emitting device, it is preferable that at least one of the group III elements Ga, Al, and In be contained in the composition of the semiconductor light emitting device. Alternatively, it is desirable that at least one of the elements belonging to Group V of As, P, and Sb be contained in the composition of the semiconductor light emitting device. Further, the semiconductor light emitting device is preferably a GaAs / AlGaAs light emitting device or an AlGaInP light emitting device.

In addition, at least one of the plurality of semiconductor elements
When each of the semiconductor light emitting devices is a semiconductor light emitting device, the semiconductor substrate of the semiconductor light emitting device is preferably a p-type, n-type, or semi-insulating GaAs substrate. Alternatively, the semiconductor substrate is a p-type, n-type, or semi-insulating substrate, and contains at least one mixed crystal of AlAs, InAs, InP, GaP, GaSb, or a mixed crystal of these. It is desirable that the substrate is a substrate containing a mixed crystal of at least one of GaAs (claim 7).

Further, in the method of manufacturing a semiconductor device according to the present invention, a first step of forming a first semiconductor element on a semiconductor substrate is opposed to a first step of forming a first semiconductor element on the semiconductor substrate at a predetermined interval. A second step of forming two insulating film masks, and selectively stacking and growing a plurality of epitaxial layers on the entire surface of the substrate excluding the two insulating film masks; A third step of forming the thickness of the plurality of epitaxial layers on the semiconductor substrate to be thicker than the plurality of epitaxial layers on the semiconductor substrate in the remaining region, and selectively etching away the plurality of epitaxial layers;
Forming a second semiconductor element comprising a plurality of epitaxial layers stacked on a semiconductor substrate, wherein the height of the second semiconductor element is lower than the height of the first semiconductor element; Forming a surface electrode of the first and second semiconductor elements, and covering the surface of a stacked body composed of a plurality of epitaxial layers on the semiconductor substrate sandwiched between the two insulating film masks with the insulating film. Forming a support having a convex shape by using a fifth support such that the height of the support having the convex shape is substantially equal to the height of the surface electrode of the first semiconductor element.
And mounting on the submount member with the surface electrodes of the first and second semiconductor elements formed on the semiconductor substrate facing downward, and disposed on the element mounting surface of the surface electrode and the submount member. And a sixth step of joining with the pattern electrode. Here, the “height” of the first and second semiconductor devices and the convex-shaped support means the height from the surface of the semiconductor substrate.

Thus, in the method of manufacturing a semiconductor device according to the eighth aspect, after forming the first semiconductor element having a relatively high height on the semiconductor substrate, a plurality of epitaxial layers are stacked on the semiconductor substrate. The plurality of epitaxial layers are selectively removed by etching to form a second semiconductor element having a relatively low height. On the semiconductor substrate sandwiched between the two opposing insulating film masks, a plurality of epitaxial layers are simultaneously formed to be thicker than the plurality of epitaxial layers constituting the second semiconductor element. A first semiconductor having a relatively high height by covering a surface of a stacked body composed of a plurality of epitaxial layers on a semiconductor substrate sandwiched between two insulating film masks with an insulating film; By forming a projecting support having substantially the same height as the semiconductor element, the surface electrodes of the first and second semiconductor elements formed on the semiconductor substrate are mounted on the submount member with the surface electrodes facing downward. In this case, even if there is a height difference between the first and second semiconductor elements, the semiconductor substrate and the submount member are substantially parallel, and the first and second semiconductor elements are horizontally lowered on the submount member. Will be mounted. Therefore, the first and second semiconductor elements are not tilted due to the difference in height and the assembly position accuracy of the semiconductor device is not reduced, and the semiconductor device according to claim 1 is manufactured. .

Further, the projection-shaped support for preventing the first and second semiconductor elements from tilting due to the difference in height is formed simultaneously with the formation of the second semiconductor element. Therefore, there is no need for a large increase in the number of steps, and there is no significant increase in cost or a large decrease in productivity.

In the method of manufacturing a semiconductor device according to the ninth aspect, the lower cladding layer, the active layer, and the upper layer constituting the semiconductor light emitting element may be formed when the plurality of epitaxial layers are grown in the third step. Preferably, at least the cladding layer is grown (claim 10). That is, in this case, a semiconductor light-emitting element is formed as the second semiconductor element, and in the case of a semiconductor light-emitting element, the assembling position accuracy has a strong influence on the characteristics, so that the effect of the present invention is more effectively exhibited. This is because that.

[0030]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described. FIG. 1 is a schematic sectional view showing a two-wavelength laser device according to one embodiment of the present invention, and FIG.
11 to 11 are process cross-sectional views for explaining a method of manufacturing the two-wavelength laser device of FIG.

As shown in FIG. 1, in the two-wavelength laser device according to the present embodiment, the output wavelength is 780 nm and the optical output is 100 to 150 m on the n-GaAs substrate 10.
AlGa for writing CD-R / RW of W
As-based infrared laser element 20 and an output wavelength of 650 nm
DVD read-only AlGaIn with optical output of 3 to 5 mW
P-type infrared laser elements 30 are respectively formed.

On the other hand, a relatively high-power AlGaAs-based infrared laser device 20 has an n-AlGaAs cladding layer 21a, an active layer 22a, a p-AlGaAs cladding layer 23a, which are sequentially stacked on an n-GaAs substrate 10. This p-
An etching stop layer 24a, a p-AlGaAs cladding layer 25a, and a p-GaAs cap layer 26a, which are sequentially stacked on the AlGaAs cladding layer 23a, a stripe ridge 27, an n-AlGaAs buried layer 28a embedding the stripe ridge 27, The active layer 22a is composed of a p-AlGaAs cladding layer 25a, a p-AlGaAs cladding layer 23a, and an n-AlGaAs layer, which are formed above and below the stripe ridge 27 and the n-AlGaAs buried layer 28a. It has a laser structure sandwiched between the cladding layer 21a.

The other relatively low output AlGaI
The nP-based infrared laser device 30 is formed of an n-GaAs substrate 10
N-AlGaInP clad layer 31 sequentially laminated on top
a, active layer 32a, p-AlGaInP cladding layer 33
a, the p-GaAs cap layer 34a, and the p-Ga
It is composed of a p-striped surface electrode 35 formed on an As cap layer 34a.
It has a laser structure sandwiched between an lGaInP cladding layer 33a and an n-AlGaInP cladding layer 31a. An n-substrate-side electrode 11 is formed on the back surface of the n-GaAs substrate 10.

Here, the active layer 22a of the AlGaAs infrared laser device 20 has a quantum well structure, and the thickness of the n-AlGaAs cladding layer 21a is 2 μm.
About p-AlGaAs cladding layer 23a and p-AlG
The combined thickness of the aAs cladding layer 25a is about 2 μm,
The thicknesses of the etching stop layer 24a and the p-GaAs cap layer 26a are 0.05 μm and 0.5 μm, respectively.
It is about. The active layer 32a in the AlGaInP-based infrared laser device 30 also has a quantum well structure, and has an n-AlGaInP cladding layer 31a and a p-Al
The thickness of the GaInP cladding layer 33a is about 1 μm, and the thickness of the p-GaAs cap layer 34a is 0.5 μm.
It is about.

When the laser structures of the AlGaAs infrared laser element 20 and the AlGaInP infrared laser element 30 are optimized as described above, the AlG
In order to enable the high output of the aAs infrared laser element 20, the n-AlG of the AlGaAs infrared laser element 20 is used.
The thickness of the aAs cladding layer 21a, the p-AlGaAs cladding layer 23a and the p-AlGaAs cladding layer 25a is n-AlGa of the AlGaInP-based infrared laser device 30.
It becomes thicker than the thickness of the InP cladding layer 31a and the p-AlGaInP cladding layer 33a. As a result, AlGaA
The height of the s-based infrared laser device 20 is higher than the height of the AlGaInP-based infrared laser device 30, and a height difference of about 2 μm is generated between the two semiconductor laser devices.

On the n-GaAs substrate 10, Al
Along with the GaAs-based infrared laser device 20 and the AlGaInP-based infrared laser device 30, the relatively high Al
The present embodiment is characterized in that a convex support 40 having a height substantially equal to that of the GaAs infrared laser element 20 is formed. This convex support 40 is made of n-GaAs.
two insulating film masks 41 and 42 made of, for example, SiO ₂ and formed on the s-substrate 10 at predetermined intervals.
And n between these two insulating film masks 41 and 42
N-AlGaI sequentially laminated on a GaAs substrate 10
nP clad layer 31, active layer 32, p-AlGaInP
It comprises a cladding layer 33, a p-GaAs cap layer 34, and an insulating film 43.

The AlGaAs infrared laser element 20, the AlGaInP infrared laser element 3
0, and n-G in which a convex support 40 is formed on the surface
With the p-surface electrode 29 of the AlGaAs-based infrared laser device 20 and the p-striped surface electrode 35 of the AlGaInP-based infrared laser device 30 turned downward, the submount substrate 51 is Submount member 5 in which pattern electrodes 52 and 53 made of In-Sn solder are formed on the element mounting surface.
It is down-mounted on 0.

That is, the AlGaAs infrared laser element 2
0 and the pattern electrode 52 of the submount member 50 are joined, and the p-stripe surface electrode 35 of the AlGaInP-based infrared laser device 30 and the pattern electrode 53 of the submount member 50 are joined. I have. At this time, the height between the surface of the n-GaAs substrate 10 and the device mounting surface of the submount member 50 is substantially the same as the height of the AlGaAs infrared laser device 20 having a relatively high height. The AlGaInP-based infrared laser element 30 and the AlGaInP-based
Even if there is a height difference of about 2 μm between the As-based infrared laser device 20 and the Al-based infrared laser device 20, the n-GaAs substrate 10 does not tilt due to the height difference. The AlGaInP-based infrared laser device 30 is horizontally down-mounted on the sub-mount member 50, and the n-substrate-side electrode 11 on the bottom surface of the sub-mount substrate 51 of the sub-mount member 50 and the back surface of the n-GaAs substrate 10. Are parallel to each other.

Next, a method of manufacturing the two-wavelength laser device shown in FIG. 1 will be described with reference to FIGS. First, as shown in FIG. 2, n-Al
GaAs cladding layer 21, active layer 22, p-AlGaAs
s cladding layer 23, etching stop layer 24, pA
An lGaAs cladding layer 25 and a p-GaAs cap layer 26 are sequentially grown.

As a crystal growth method at this time, for example, a metal organic chemical vapor deposition method or the like is used. Also, the active layer 2
2, a quantum well structure is formed. Also, n-AlGa
The thickness of the As cladding layer 21 is about 2 μm, and p-AlGa
As clad layer 23 and p-AlGaAs clad layer 25
The combined thickness is about 2 μm, and the etching stop layer 2
The thicknesses of the cap layer 4 and the p-GaAs cap layer 26 are about 0.05 μm and about 0.5 μm, respectively.

Next, as shown in FIG.
As cap layer 26, p-AlGaAs clad layer 2
5, the etching stop layer 24 is selectively removed by etching, and the etching stop layer 24
a, p-AlGaAs cladding layer 25a, and p-Ga
A stripe ridge 27 made of an As cap layer 26a is formed.

Next, as shown in FIG.
An n-AlGaAs buried layer 28 is selectively grown on the GaAs cladding layer 23. Thus, this n-A
The stripe ridge 27 is embedded in the lGaAs embedded layer 28.

Next, as shown in FIG.
GaAs buried layer 28, p-AlGaAs clad layer 23, active layer 22, and n-AlGaAs clad layer 2
1 is selectively removed by etching to form an n-GaAs substrate 1
N-AlGaAs cladding layer 21 sequentially laminated on
a, active layer 22a, p-AlGaAs cladding layer 23
a, and stripe ridge 27 and n-AlGaAs
The main part of the AlGaAs-based infrared laser device 20 including the buried layer 28a is formed. Also. At the same time, the surface of the n-GaAs substrate 10 in the other region is exposed again.

Next, as shown in FIG. 6, on the exposed n-GaAs substrate 10, two opposing insulating film masks 41 and 42 are formed at a predetermined interval. As a material of these two insulating film masks 41 and 42, for example, SiO ₂ or the like is used.

Next, as shown in FIG. 7, the n-AlGaInP cladding layer 31, the active layer 32 and the active layer 32 are formed on the entire surface of the substrate except for the two insulating film masks 41 and 42 by using, for example, metal organic chemical vapor deposition. The p-AlGaInP cladding layer 33 and the p-GaAs cap layer 34 are selectively grown in layers.

The n-AlGaInP cladding layer 31, the active layer 32, the p-AlGaInP cladding layer 33, and the p-GaAs cap layer 34 will be
The main part of the aInP-based infrared laser device 30 is constituted by the AlGaInP-based infrared laser device 30.
Is formed, the thickness of each of the n-AlGaInP cladding layer 31 and the p-AlGaInP cladding layer 33 is about 1 μm, and the thickness of the p-GaAs cap layer 34 is about 0.5 μm.

At this time, the two insulating film masks 4
Since no crystal growth occurs on 1 and 42,
N-G sandwiched between these two insulating film masks 41 and 42
On the aAs substrate 10, adjacent insulating film masks 41, 4
2 Raw materials for crystal growth diffuse from above. Due to the effect of the migration of the raw material, the insulating film mask 4
On the n-GaAs substrate 10 sandwiched between the first and the second 42, a larger amount of raw material is supplied than on the n-GaAs substrate 10 in a region where the AlGaInP-based infrared laser device 30 is formed. And the speed of crystal growth increases.

For this reason, the n-AlG grown on the n-GaAs substrate 10 sandwiched between the insulating film masks 41 and 42 is grown.
aInP clad layer 31, active layer 32, p-AlGaI
nP cladding layer 33 and p-GaAs cap layer 34
The thickness of the active layer 3 and the n-AlGaInP cladding layer 31 grown on the n-GaAs substrate 10 in the region where the remaining AlGaInP-based infrared laser device 30 is formed
2, p-AlGaInP cladding layer 33, and p-Ga
Each thickness becomes larger than the thickness of the As cap layer 34.

Next, as shown in FIG.
As cap layer 34, p-AlGaInP clad layer 3
3, active layer 32, and n-AlGaInP cladding layer 3
1 is selectively etched to remove a portion covering a main portion of the AlGaAs infrared laser device 20;
While exposing the stripe ridge 27 and the n-AlGaAs buried layer 28a, etc., the n-AlGaInP cladding layer 31a, the active layer 32a,
p-AlGaInP cladding layer 33a and p-GaAs
The main portion of the AlGaInP-based infrared laser device 30 on which the s cap layer 34a is sequentially stacked is formed separately from the main portion of the AlGaAs-based infrared laser device 20.

Here, the n-AlGaAs cladding layer 21
a, active layer 22a, p-AlGaAs cladding layer 23
a, and stripe ridge 27 and n-AlGaAs
The main part of the AlGaAs infrared laser device 20 comprising the buried layer 28a and the n-AlGaInP cladding layer 3
1a, active layer 32a, p-AlGaInP clad layer 3
3a and Al made of a p-GaAs cap layer 34a
Comparing with the main part of the GaInP-based infrared laser device 30, the n-Al
The thickness of the GaAs cladding layer 21a, the p-AlGaAs cladding layer 23a and the p-AlGaAs cladding layer 25a is n-AlG of the AlGaInP-based infrared laser device 30.
Since the thicknesses of the aInP cladding layer 31a and the p-AlGaInP cladding layer 33a are thicker,
Stripe ridge 27 of aAs infrared laser device 20
P-G of the surface of the AlGaInP-based infrared laser device 30
The height is higher than the surface of the aAs cap layer 34.

On the other hand, an AlGaAs infrared laser element 2
0 and n− between the insulating film masks 41 and 42.
Comparing the convex-shaped laminated body composed of the n-AlGaInP clad layer 31, the active layer 32, the p-AlGaInP clad layer 33, and the p-GaAs cap layer 34 grown on the GaAs substrate 10, both have almost the same height. It has become.

Next, as shown in FIG.
The n-substrate-side electrode 11 is formed on the back surface of the As substrate 10, and the p-surface electrode 29 of the AlGaAs infrared laser device 20 is formed on the stripe ridge 27 and the n-AlGaAs buried layer 28a. Layer 3
P- of the AlGaInP-based infrared laser device 30
A stripe surface electrode 35 is formed, and
The As-based infrared laser device 20 and the AlGaInP-based infrared laser device 30 are completed. At this time, AlG
The height of the p-surface electrode 29 of the aAs-based infrared laser device 20 is higher than the height of the p-striped surface electrode 35 of the AlGaInP-based infrared laser device 30, and between the two is, for example, about 2 μm. A height difference occurs.

Further, n-AlG grown sequentially on the n-GaAs substrate 10 sandwiched between the insulating film masks 41 and 42.
aInP clad layer 31, active layer 32, p-AlGaI
nP cladding layer 33 and p-GaAs cap layer 34
An insulating film 43 is formed to cover the surface of the convex-shaped laminate made of. Thus, the n-Al layer sequentially grown on the n-GaAs substrate 10 sandwiched between the insulating film masks 41 and 42 is formed.
GaInP clad layer 31, active layer 32, p-AlGa
InP cladding layer 33, p-GaAs cap layer 34,
Then, a convex-shaped support body 40 made of a convex-shaped laminated body composed of the insulating film 43 is formed. At this time, the height of the convex support 40 is set to be substantially equal to the height of the p-surface electrode 29 of the AlGaAs infrared laser device 20.

Next, as shown in FIGS. 10 and 11, the AlGaAs infrared laser element 20, the AlGaI
nP-based infrared laser element 30 and convex support 40
Inverts the n-GaAs substrate 10 formed on the surface,
P-surface electrode 2 of AlGaAs infrared laser element 20
9 and the AlGaInP-based infrared laser device 30 are mounted on the submount member 50 with the p-striped surface electrode 35 facing downward. The sub-mount member 50 has pattern electrodes 52 and 53 made of In-Sn-based solder on the element mounting surface of the sub-mount substrate 51, respectively.

In this way, the p-surface electrode 29 of the AlGaAs infrared laser device 20 and the pattern electrode 52 of the submount member 50 are joined, and the p-stripe surface electrode 35 of the AlGaInP infrared laser device 30 is The pattern electrode 53 of the mount member 50 is joined. At this time, the height between the surface of the n-GaAs substrate 10 and the device mounting surface of the submount member 50 is substantially the same as the height of the AlGaAs infrared laser device 20 having a relatively high height. The height of the AlGaInP-based infrared laser device 30 is A because the submount member 50 having
Even if the height is lower than the height of the lGaAs infrared laser element 20, n-G
The aAs substrate 10 does not tilt. That is, AlGaAs
The system infrared laser element 20 and the AlGaInP system infrared laser element 30 are horizontally mounted on the submount member 50, respectively, and the n-GaAs substrate 10 bottom surface of the submount member 50 and the n-GaAs substrate The substrate-side electrodes 11 are parallel to each other.

As described above, according to this embodiment, nG
An n-AlGaAs cladding layer 21a, an active layer 22a, a p-AlGaAs cladding layer 23a, and a p-AlGaAs cladding layer 23a sequentially laminated on the aAs substrate 10.
The etching stop layers 24a, p-
A stripe ridge 27 composed of an AlGaAs cladding layer 25a and a p-GaAs cap layer 26a, and n-AlGa embedding the stripe ridge 27
After forming the main part of the relatively high AlGaAs infrared laser element 20 composed of the As buried layer 28a, the n-AlGaInP is formed on the n-GaAs substrate 10.
The clad layer 31, the active layer 32, the p-AlGaInP clad layer 33, and the p-GaAs cap layer 34 are selectively stacked and grown, and these stacked layers are selectively etched to form the n-GaAs substrate 10. N stacked in order
-AlGaInP cladding layer 31a, active layer 32a, p
-AlGaInP cladding layer 33a and p-GaAs
A having a relatively low height composed of the cap layer 34a
The main part of the 1GaInP-based infrared laser device 30 is formed, and these n-AlGaInP cladding layers 31 and
During the stacked growth of the active layer 32, the p-AlGaInP cladding layer 33, and the p-GaAs cap layer 34, n-GaAs sandwiched between two opposing insulating film masks 41, 42 at a predetermined interval. N-AlG on the substrate 10
aInP clad layer 31, active layer 32, p-AlGaI
nP cladding layer 33 and p-GaAs cap layer 34
Is formed at the same time, and the thickness of the convex laminate is reduced to n-A by increasing the crystal growth rate due to the effect of the migration of the crystal growth raw material.
1GaInP cladding layer 31a, active layer 32a, p-A
The thickness of the main part of the AlGaInP-based infrared laser device 30 including the lGaInP cladding layer 33a and the p-GaAs cap layer 34a is made larger than the thickness of the main part, and the surface of the convex laminate is covered with an insulating film 43. This n-
AlGaInP clad layer 31, active layer 32, p-Al
GaInP cladding layer 33, p-GaAs cap layer 3
4 and the convex support 40 made of the insulating film 43 are connected to the relatively high AlGaAs infrared laser device 20.
The height of the n-GaAs substrate 1 is substantially the same as that of the n-GaAs substrate 1.
AlGaAs infrared laser element 20 formed on
When the AlGaInP-based infrared laser device 30 is down-mounted on the sub-mount member 50, n-GaAs
Since the submount member 50 having a height substantially equal to the height of the AlGaAs infrared laser element 20 is interposed between the surface of the s substrate 10 and the element mounting surface of the submount member 50, the AlGaAs type Infrared laser element 20 and Al
Even if there is a height difference of about 2 μm between the GaInP-based infrared laser device 30 and AlGaA
The s-based infrared laser device 20 and the AlGaInP-based infrared laser device 30 are not tilted, and the AlGaAs-based infrared laser device 20 and the AlGaInP-based infrared laser device 30 are horizontally lowered on the submount member 50. Can be mounted.

For this reason, the AlGaAs infrared laser elements 20 and AlGaInP infrared laser elements 20 and AlGaInP infrared laser elements 30 are reduced due to a decrease in assembly position accuracy due to a difference in elevation between the AlGaAs infrared laser elements 20 and AlGaInP infrared laser elements 30 as in the prior art.
The position shift of the light emitting point of the InP-based infrared laser element 30 occurs, the distance between the light emitting points is shortened, and the optical axis shift is caused, thereby causing characteristic defects such as making alignment of an optical system such as an optical pickup difficult. This makes it possible to prevent the situation, and to realize a two-wavelength laser device having stable characteristics and high reliability.

The n-type substrate-side electrode 11 on the back surface of the n-GaAs substrate 10
Since the surface is also horizontal and parallel to the bottom surface of the submount substrate 51 of the submount member 50, wire bonding on the n-substrate-side electrode 11 can be easily and accurately performed.

In the case of down mounting, AlGaAs
The oblique pressure is not applied to the infrared laser element 20 and the AlGaInP infrared laser element 30, and A
lGaAs infrared laser element 20 and AlGaInP
Since distortion does not occur in the system infrared laser device 30, it is possible to prevent the polarization angle from being varied or causing a defect during light emission, and to improve the characteristics of the two-wavelength laser device.

Further, an AlGaAs infrared laser device 2
The convex-shaped support body 40 which prevents the 0 and AlGaInP-based infrared laser elements 30 from being tilted due to the difference in height thereof has a main part formed when forming the AlGaInP-based infrared laser elements 30. Since it is formed simultaneously, it does not require a large increase in the number of steps, and prevents a significant increase in cost and a significant decrease in productivity as compared with the case of forming using an independent separate process. be able to.

[0061]

As described above, according to the semiconductor device and the method of manufacturing the same of the present invention, the following effects can be obtained. That is, according to the semiconductor device of the first aspect, in a state where the plurality of semiconductor elements formed on the semiconductor substrate are mounted on the submount member,
A convex support formed on the semiconductor substrate is interposed between the semiconductor substrate surface and the element mounting surface of the submount member, and the convex support is formed on the semiconductor substrate. Has the same height as the tallest semiconductor element among the plurality of semiconductor elements, even if the height of the plurality of semiconductor elements is different and the height difference between the plurality of semiconductor elements is different. However, the semiconductor substrate and the submount member are substantially parallel, and the plurality of semiconductor elements can be horizontally mounted on the submount member. For this reason, it is possible to prevent the plurality of semiconductor elements down-mounted on the sub-mount member from being inclined due to the height difference between the plurality of semiconductor elements, thereby preventing a decrease in assembly position accuracy of the semiconductor device. Thus, a semiconductor device having stable characteristics and high reliability can be realized.

Further, when a plurality of semiconductor elements formed on the semiconductor substrate are down-mounted on the sub-mount member, no oblique pressure is applied to each of the semiconductor elements. It is possible to prevent the semiconductor device from being caused to cause the characteristic failure, thereby contributing to achieving stable characteristics and high reliability of the semiconductor device.

The substrate-side electrode surface, which is exposed upward with the down-mounting, is also horizontal and parallel to the bottom surface of the submount member, so that wire bonding on this lower electrode surface can be performed easily and easily. This can be performed with high accuracy, which can contribute to achieving stable characteristics and high reliability of the semiconductor device.

Further, in order to horizontally mount the plurality of semiconductor elements on the submount member, a plurality of semiconductor elements may be provided with surface electrodes having different thicknesses, or the surface electrodes of the plurality of semiconductor elements may be connected to the submount. Compared with the conventional case in which a solder layer having a different thickness is interposed between the member and the pattern electrode, a rise in cost due to an increase in the electrode material and a decrease in productivity due to complicated processes are prevented.

According to a second aspect of the present invention, in the semiconductor device according to the first aspect, at least one of the plurality of semiconductor elements is a semiconductor light emitting element. When mounted horizontally on a member, it prevents optical axis displacement due to the displacement of the light emitting point, and thus prevents poor alignment of the optical system, etc.
Its optical characteristics can be improved.

Further, when the semiconductor light emitting device formed on the semiconductor substrate is down-mounted on the sub-mount member, no oblique pressure is applied to the semiconductor light emitting device. Gone
It is possible to prevent variations in the polarization angle at the time of light emission or to cause a defect, thereby contributing to an improvement in optical characteristics.

According to the method of manufacturing a semiconductor device of the present invention, after forming the first semiconductor element having a relatively high height on the semiconductor substrate, a plurality of epitaxial layers are stacked on the semiconductor substrate. The plurality of epitaxial layers are selectively removed by etching to form a second semiconductor element having a relatively low height. On the semiconductor substrate sandwiched between the two opposing insulating film masks, a plurality of epitaxial layers are simultaneously formed to be thicker than the plurality of epitaxial layers constituting the second semiconductor element. A first semiconductor element having a relatively high height by covering a surface of a stacked body including a plurality of epitaxial layers on a semiconductor substrate sandwiched between two insulating film masks with an insulating film; By forming the protrusion-shaped support having the same height, the formed on a semiconductor substrate 1
When mounting the semiconductor device on the submount member with the surface electrode of the second semiconductor device facing down, even if there is a height difference between the first and second semiconductor devices, the semiconductor substrate and the submount member are substantially parallel to each other. Thus, the first and second semiconductor elements can be horizontally down-mounted on the sub-mount member. Therefore, the first and second semiconductor elements are not tilted due to the difference in height, and the assembly position accuracy of the semiconductor device is not reduced, and the semiconductor device according to claim 1 is easily manufactured. Therefore, the same effect as the effect of the first aspect can be obtained.

Further, the convex support member for preventing the first and second semiconductor elements from tilting due to the difference in height is formed simultaneously with the formation of the second semiconductor element. Therefore, a large increase in the number of steps is not required, and a large increase in cost and a large decrease in productivity can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a two-wavelength laser device according to one embodiment of the present invention.

FIG. 2 is a process sectional view (part 1) for describing a method for manufacturing the two-wavelength laser device of FIG.

FIG. 3 is a process sectional view (part 2) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 4 is a process sectional view (part 3) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 5 is a process sectional view (part 4) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 6 is a process sectional view (part 5) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 7 is a process sectional view (part 6) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 8 is a process sectional view (part 7) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 9 is a process sectional view (part 8) for describing the method for manufacturing the two-wavelength laser device of FIG.

10 is a process sectional view (No. 9) for describing the method of manufacturing the two-wavelength laser device in FIG.

FIG. 11 is a process sectional view (part 10) for describing the method for manufacturing the two-wavelength laser device of FIG.

FIG. 12 is a schematic cross-sectional view (part 1) showing a state in which two different types of semiconductor laser elements formed on the same semiconductor substrate are down-mounted on a sub-mount member by a conventional method.

FIG. 13 is a schematic sectional view (part 2) showing how two different types of semiconductor laser elements formed on the same semiconductor substrate are down-mounted on a sub-mount member by a conventional method.

FIG. 14 is a schematic cross-sectional view (part 3) showing a state in which two different types of semiconductor laser elements formed on the same semiconductor substrate are down-mounted on a sub-mount member by a conventional method.

[Explanation of symbols]

10 ... n-GaAs substrate, 11 ... n-substrate side electrode,
20... AlGaAs infrared laser element, 21, 21
a ... n-AlGaAs cladding layer, 22, 22a ...
Active layer, 23, 23a p-AlGaAs cladding layer, 24, 24a Etching stop layer, 25, 2
5a ... p-AlGaAs cladding layer, 26, 26a ...
... p-GaAs cap layer, 27 ... stripe ridge, 28, 28a ... n-AlGaAs buried layer, 2
9: p-surface electrode, 30: AlGaInP-based infrared laser element, 31, 31a: n-AlGaInP clad layer, 32, 32a: active layer, 33, 33a, p
-AlGaInP cladding layer, 34, 34a ... pG
aAs cap layer, 35... p-stripe surface electrode,
40 ... a convex support, 41, 42 ... an insulating film mask, 43 ... an insulating film, 50 ... a submount member, 51
... Submount base, 52, 53... Pattern electrodes.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) H01S 5/22 610 (72) Inventor Yoshinobu Higuchi 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Stock In-company F term (reference) 5F041 CA34 CA36 CB29 DA04 DA09 DA19 DA20 5F073 AB06 BA04 CA05 CA14 CB02 EA15 FA11 FA22 FA23

Claims (9)

[Claims] A plurality of semiconductor elements formed on a semiconductor substrate, each of the plurality of semiconductor elements having a plurality of pattern electrodes corresponding to the respective surface electrodes with the respective surface electrodes facing downward; A semiconductor device mounted on a mounting member, wherein a convex support formed on the semiconductor substrate is interposed between the semiconductor substrate surface and an element mounting surface of the submount member. A semiconductor device, wherein the projection-shaped support has a height substantially equal to the highest semiconductor element of the plurality of semiconductor elements. 2. The semiconductor device according to claim 1, wherein at least one of the plurality of semiconductor elements is a semiconductor light emitting element. 3. The semiconductor device according to claim 3, wherein in the composition of the semiconductor light emitting element, Ga that is a Group 3 element,
A semiconductor device comprising at least one element of Al and In. 4. The semiconductor device according to claim 3, wherein the composition of the semiconductor light emitting element includes As, which is a Group 5 element,
A semiconductor device comprising at least one element of P and Sb. 5. The semiconductor device according to claim 3, wherein the semiconductor light emitting element is a GaAs / AlGaAs light emitting element or an AlGaInP light emitting element. 6. The semiconductor device according to claim 3, wherein said semiconductor substrate is formed of p-type, n-type, or semi-insulating GaAs.
A semiconductor device, which is an s substrate. 7. The semiconductor device according to claim 3, wherein the semiconductor substrate is a p-type, n-type, or semi-insulating substrate, and is composed of AlAs, InAs, InP, GaP, and GaS.
b. A semiconductor device comprising a substrate containing at least one mixed crystal of b or a mixed crystal of at least one of these mixed crystals and GaAs. 8. A first step of forming a first semiconductor element on a semiconductor substrate, and a second step of forming two opposing insulating film masks at a predetermined interval on the semiconductor substrate. And selectively growing a plurality of epitaxial layers on the entire surface of the substrate except for the two insulating film masks.
A third step of forming the plurality of epitaxial layers on the semiconductor substrate sandwiched between two insulating film masks to be thicker than the plurality of epitaxial layers on the semiconductor substrate in the remaining region; The plurality of epitaxial layers are selectively removed by etching to form a second semiconductor element including the plurality of epitaxial layers stacked on the semiconductor substrate. At this time, the height of the second semiconductor element is A fourth step of making the height lower than the height of the first semiconductor element; and forming the surface electrodes of the first and second semiconductor elements and the semiconductor sandwiched between the two insulating film masks. The surface of the stacked body composed of the plurality of epitaxial layers on the substrate is covered with an insulating film to form a convex support, and the height of the convex support is the first semiconductor. A fifth step of making the height substantially equal to the height of the front surface electrode of the device; and a submount member with the front surface electrodes of the first and second semiconductor elements formed on the semiconductor substrate facing downward. And bonding the surface electrode and the pattern electrode disposed on the element mounting surface of the submount member. 6. A method for manufacturing a semiconductor device, comprising: 9. The method for manufacturing a semiconductor device according to claim 8, wherein, during the step of growing the plurality of epitaxial layers in the third step, the lower clad layer, the active layer, and the upper layer constituting the semiconductor light emitting element. A method for manufacturing a semiconductor device, comprising growing a cladding layer.