JP2002270965A - Semiconductor device and semiconductor light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device and a semiconductor light emitting device in which a crystal defect can be suppressed by relaxing strain caused by different physical properties even if semiconductor layers having different physical properties, e.g. a coefficient of thermal expansion or the like, are laid in layer. SOLUTION: The semiconductor device has a first semiconductor region, e.g. a substrate 10, and a second semiconductor region of a multilayer semiconductor ST comprising a strain relaxing film 11 provided at a one region on the first semiconductor region substrate, an at least a first clad layer of a first conductivity type, a first active layer 14 and a second clad layer of a second conductivity type provided on the first semiconductor region provided with no strain relaxing film 11 and on the strain relaxing film 11 and having specified physical properties, e.g. a coefficient of thermal expansion, different from those of the first semiconductor region. Strain caused by the different physical properties between the first and second semiconductor regions can be relaxed by the strain relaxing film 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a semiconductor light emitting device, and more particularly to a semiconductor device and a semiconductor light emitting device capable of structurally alleviating distortion generated when heat is generated.

[0002]

2. Description of the Related Art Today, a laser diode, which is one of the semiconductor light emitting devices, is a compact disk (CD) or a compact disk (DVD).
It is widely used in various fields as a light source for reproduction or recording in an optical disk device such as a (digital versatile disk) or in other electronic devices. In particular, a high-power laser diode that enables high output such as a W (watt) class is applied to various fields such as laser processing and plays an important role in industry.

FIG. 5A is a perspective view showing a schematic configuration of a laser diode which oscillates a laser beam in a near infrared region such as a 780 nm band. For example, a semiconductor stacked body ST including an active layer 14 is formed on an n-type substrate 10. The n-type substrate 10 is made of, for example, a GaAs-based material, and the semiconductor stacked body ST is made of an AlGaAs-based material.

FIG. 5B is a sectional view showing a more detailed layer structure of the laser diode of FIG. 5A. That is, for example, on an n-type substrate 10 of GaAs, for example, AlG
n-type cladding layer 12 made of aAs, for example, AlGaAs
s, the active layer 14 having a multiple quantum well structure (oscillation wavelength 780 nm) made of AlGaAs, for example, the second optical guide layer 1 made of AlGaAs
5, a p-type cladding layer 16 made of, for example, AlGaAs,
For example, a p-type contact layer 17 made of GaAs is laminated. Further, the p-type cladding layer 1 is removed from the surface of the p-type contact layer 17 except for the region serving as the current injection stripe.
An n-type current stop layer 18 made of, for example, GaAs is formed in the region up to the middle depth of 6, forming a stripe having a current confinement structure. As described above,
A semiconductor laminate ST is formed. In the above, n
For example, each of the type semiconductor layers is doped with Se, and each of the p-type semiconductor layers is doped with Zn, for example.

Further, a p-electrode 19a such as Ti / Pt / Au is formed so as to be connected to the p-type contact layer 17, while AuGe is formed so as to be connected to the n-type substrate 10.
An n electrode 19b of / Ni / Au or the like is formed.

In the above-mentioned laser diode, since the lattice constant of GaAs forming the semiconductor substrate 10 and AlGaAs forming the semiconductor stacked body ST hardly change, there is no problem even if lattice matching is not particularly taken into consideration. There is an advantage that the semiconductor stacked body ST can be stacked on the substrate.

FIG. 6A is a schematic view of a laser array in which several tens of laser diodes having the above-described configuration are integrated in parallel, and FIG.
FIG. 3 is a perspective view illustrating a schematic configuration of a portion corresponding to an individual laser diode. On the common n-type substrate 10, the semiconductor laminate ST having the above-described configuration including at least the n-type cladding layer, the active layer, and the p-type cladding layer is formed corresponding to each laser diode. By integrating several tens of laser diodes, the light output can be increased to the watt class, and is used industrially.

[0008]

However, a laser diode in recent years is required to have a high light output of, for example, about 200 mW or more, and realize a higher output as in the above-described laser array. In a situation where a configuration that performs
In a configuration in which an AlGaAs-based semiconductor laminated body is laminated on an As-based semiconductor substrate, although no distortion occurs during the lamination, there is a difference in thermal expansion coefficient between the GaAs-based material and the AlGaAs-based material. At the time of heat generation when used, GaAs-based material and AlGa
There arises a problem that strain occurs between As-based materials. When the magnitude of the strain increases, dislocations of the crystal are introduced due to the strain, which grows, and the function as a laser diode is lost.

FIG. 7A is a schematic diagram of the above-mentioned laser array at the time of use.
This shows a state in which a difference occurs in thermal expansion between the s-based semiconductor substrate and the AlGaAs-based semiconductor laminate, and the entire laser array warps. For example, the size of the laser array is 10 m in the direction in which several tens of laser diodes are arranged.
m, about 1 mm in the resonator direction, the magnitude of the warpage reaches 10 μm. Usually, a laser diode such as a laser array as described above is used by being fixed to a heat sink or the like. Therefore, distortion occurs when the above-described warpage occurs. For example, as shown in a schematic configuration diagram of FIG. 7B, an n-type semiconductor substrate 10 and an n-type cladding layer 12 are formed.
Interface, the p-type cladding layer 16 and the n-type current blocking layer 1
When the dislocations T of the crystal are generated and multiplied from the interface with the crystal 8 and reach the light emitting region R, the laser oscillation capability is extremely reduced, and the light output is greatly reduced.

The problem of crystal dislocation due to the above-described device distortion is not limited to a semiconductor light emitting device such as a laser diode and the like. This is a fundamental problem when the heat generation of the device is large enough to cause a strain that generates and proliferates.

[0011] The present invention has been made in view of the above situation, and therefore, the present invention eliminates the distortion generated due to different physical properties even when semiconductor layers having different physical properties such as thermal expansion coefficients are stacked. It is an object of the present invention to provide a semiconductor device and a semiconductor light emitting device which can relax and suppress dislocation of a crystal.

[0012]

In order to achieve the above object, a semiconductor device according to the present invention comprises a first semiconductor region, a strain relaxation film provided in one region on the first semiconductor region substrate, Provided on the first semiconductor region and on the strain relaxation film in a region where the strain relaxation film is not provided,
A second semiconductor region having a predetermined physical property different from that of the first semiconductor region.
A semiconductor region, wherein a strain caused by different physical properties between the first semiconductor region and the second semiconductor region is relaxed by the strain relaxation film.

The semiconductor device according to the present invention is preferably
The first semiconductor region and the second semiconductor region have different thermal expansion coefficients as the different physical properties.

Preferably, the above-described semiconductor device of the present invention
The strain relaxation film is bonded at least at the interface with the first semiconductor region or the second semiconductor region by substantially van der Waals force. Alternatively, preferably, the strain relaxation film is a layered semiconductor layer.

In the semiconductor device of the present invention, the first semiconductor region and the first semiconductor region are partially formed at the interface between the first semiconductor region and the second semiconductor region having predetermined physical properties different from each other.
A strain relieving film for relieving strain due to physical properties different from that of the semiconductor region is provided, so that dislocation of crystals can be suppressed.

According to another aspect of the present invention, there is provided a semiconductor light emitting device, comprising: a semiconductor substrate of a first conductivity type; a strain relief film provided in one region on the semiconductor substrate;
At least a first cladding layer of the first conductivity type, a first active layer, and a second cladding layer of the second conductivity type are laminated on the semiconductor substrate and the strain relaxation film in a region where the strain relaxation film is not provided. The semiconductor substrate and the semiconductor laminate have different predetermined physical properties, and the strain caused by the different physical properties of the semiconductor substrate and the semiconductor laminate is reduced by the strain relaxation film. It is configured to relax.

In the semiconductor light emitting device of the present invention, preferably, the semiconductor substrate and the semiconductor laminate have different thermal expansion coefficients as the different physical properties. More preferably, the semiconductor substrate and the semiconductor laminate have substantially the same lattice constant.

In the above semiconductor light emitting device of the present invention, preferably, the semiconductor substrate and the semiconductor laminate are each a compound semiconductor region. For example, the semiconductor substrate is Ga
Made of an As-based material, and the semiconductor laminate region is made of AlG
It is made of an aAs-based material.

In the above-described semiconductor light emitting device of the present invention, preferably, the strain relaxation film is bonded at least at an interface with the semiconductor substrate or the semiconductor laminate by substantially van der Waals force. For example, the strain relaxation film is a silicon oxide film or a silicon nitride film.

In the above-described semiconductor light emitting device of the present invention, preferably, the strain relaxation film is a layered semiconductor layer. For example, the strain relaxation film is a Ga ₂ Se ₃ film.

The semiconductor light emitting device of the present invention is preferably arranged such that at least a first conductive type first light-emitting device is provided on the semiconductor substrate.
A plurality of semiconductor laminates in which a clad layer, a first active layer, and a second conductive type second clad layer are laminated are integrated, and each of the plurality of semiconductor laminates constitutes a semiconductor light emitting device. More preferably, in the plurality of semiconductor laminates, a groove reaching the strain relief film or the semiconductor substrate is provided between one semiconductor laminate and another semiconductor laminate.

In the semiconductor light emitting device of the present invention described above, the semiconductor substrate and the semiconductor laminate have different physical properties such as thermal expansion coefficients, and at least a first conductive type first cladding layer, a first active layer and a first active layer. At a part of the interface with the semiconductor laminate in which the two-conductivity-type second clad layer is laminated, a strain relaxation film for relieving strain caused by different physical properties between the semiconductor substrate and the semiconductor laminate is provided. In addition, dislocation of the crystal can be suppressed.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a semiconductor light emitting device and a method of manufacturing the same according to the present invention will be described below with reference to the drawings.

First Embodiment A semiconductor light emitting device according to this embodiment has a thickness of, for example, 780 nm.
This is a laser diode that oscillates laser light in the near infrared region such as a band. FIG. 1A is a perspective view illustrating a schematic configuration of a laser diode according to the present embodiment. For example, a strain relaxation film 11 is formed in one region on the n-type substrate 10. Further, a semiconductor stacked body ST including an active layer 14 is formed on the n-type substrate 10 and the strain relaxation film 11 in a region where the strain relaxation film 11 is not provided. The n-type substrate 10 is made of, for example, a GaAs-based material, and the semiconductor stacked body ST is made of an AlGaAs-based material. Further, the strain relaxation film 11 is a film substantially bonded by van der Waals force at least at an interface with the n-type substrate 10 or the semiconductor stacked body ST, such as a silicon oxide film or a silicon nitride film, or , G
It is a layered semiconductor layer such as an a ₂ Se ₃ film.

FIG. 1B shows the laser diode of FIG.
FIG. 4 is a cross-sectional view showing a more detailed layer configuration of the card. That is, an example
For example, in one region on the n-type substrate 10 made of GaAs.
Thus, the strain relaxation film 11 is formed, and the strain relaxation film 1 is formed.
1 on the n-type substrate 10 in a region where the
And a film having a thickness of, for example, about 1500 nm
Al_0.4Ga_0.6 Example of n-type cladding layer 12 made of As
For example, Al having a thickness of about 10 nm_{0. Three} Ga_0.7 From As
The first light guide layer 13 having a thickness of, for example, about 10 nm
l _0.1 Ga_0.9 As quantum well of 10 nm
Al with moderate thickness_0.3 Ga _0.7 A barrier layer made of As
Of multiple quantum well structure (oscillation wavelength 780 nm) composed of
Layer 14, for example, Al having a thickness of about 10 nm_0.3 Ga
_0.7 The second light guide layer 15 made of As, for example, 1200
Al with a thickness of about nm_0.4 Ga_0.6 As-type p-type
Rad layer 16, for example, a p-type contact made of GaAs
Layer 17 is laminated. In addition, the current injection stripe
Except for the region where
In the region up to the middle depth of the mold cladding layer 16, for example, G
An n-type current stop layer 18 made of aAs is formed.
Thus, the stripe has a current constriction structure. that's all
Thus, the semiconductor stacked body ST is formed. Up
In the above description, for example, Se is doped in each of the n-type semiconductor layers.
Each of the p-type semiconductor layers has, for example, Zn
Is doped.

Further, a p-electrode 19a of Ti / Pt / Au or the like is formed so as to connect to the p-type contact layer 17, while AuGe is connected so as to connect to the n-type substrate 10.
An n electrode 19b of / Ni / Au or the like is formed.

When a predetermined voltage is applied to the p-electrode 19a and the n-electrode 19b, a current is injected while being narrowed by the n-type current stop layer 18, and the active layer is moved in the resonator direction D shown in FIG. 14 emits a laser beam having a predetermined wavelength in the 780 nm band, for example.

Here, the current is confined also by the stripe width of the strain relaxation film 11. The strain relaxation film 11 is provided on the side of the n-type cladding layer 12 and has high mobility of electrons as carriers.
Is relatively thick, electrons can be uniformly injected into the light emitting region of the active layer, but the width (strain) of the region where the strain relaxation film 11 is not provided with respect to the width x of the entire laser diode. The stripe width y of the relaxation film 11 is set in a range that does not affect the laser characteristics. For example, when the width x of the entire laser diode is 300 μm,
The stripe width y of the strain relaxation film 11 is set to about 100 μm, for example, so that y / x ≧ 0.3.

In the above-described laser diode according to the present embodiment, since the lattice constant of GaAs forming the semiconductor substrate 10 and AlGaAs forming the semiconductor laminate ST hardly change, there is no problem even if lattice matching is not particularly taken into consideration. There is an advantage that the semiconductor stacked body ST can be stacked on the semiconductor substrate 10 without any additional steps. On the other hand, Ga
Since there is a difference in the thermal expansion coefficient between the As-based material and the AlGaAs-based material, distortion occurs between the GaAs-based material and the AlGaAs-based material during heat generation when used as a laser diode. However, the strain relaxation film 11 is formed at the interface with the n-type substrate 10 or the semiconductor stacked body ST. The strain relaxation film 11 is made of an n-type substrate 1 such as a silicon oxide film or a silicon nitride film.
0 or a film substantially bonded by Van der Waals force at the interface with the semiconductor stacked body ST, when a strain is applied, the bond is easily cut on the surface of the strain relaxation film 11, and the n-type Substrate 10 or semiconductor laminate ST
The surface of the crystal and the surface of the strain relaxation film 11 slip in the direction of absorbing the strain, and the effect of expansion and contraction of the crystal is not easily transmitted, and the crystal is generated due to a difference in thermal expansion coefficient as described above. Distortion can be reduced. When the strain relaxing film 11 is a layered semiconductor layer such as a Ga ₂ Se ₃ film, for example, when a strain is applied, σ in the strain relaxing film 11 is reduced.
The interface between the layers of the layered semiconductor composed of the π bond weaker than the bond is shifted in the direction of absorbing the strain, and the influence of the expansion and contraction of the crystal is difficult to be transmitted, and is caused due to the difference in thermal expansion coefficient as described above. Distortion can be reduced.

As described above, in the laser diode according to the present embodiment, the n-type substrate and the semiconductor laminate have different physical properties such as the thermal expansion coefficient, and distortion occurs due to the difference in physical properties. Also, the strain can be relaxed by the strain relieving film formed at the interface between the n-type substrate and the semiconductor laminate. Thereby, the energy required for generating the dislocation can be reduced, and the energy given to the dislocation can be reduced, so that the dislocation can be prevented from growing. Further, regarding high-concentration impurities introduced into the contact layer and the like, unnecessary diffusion of impurities due to strain can be suppressed. In a laser diode or the like having a high output which has been particularly required in recent years, it is possible to realize an improvement in performance such as an improvement in reliability by suppressing dislocations and suppressing impurity diffusion. Further, the amount of warpage of the laser diode due to distortion during heat generation is reduced, and bonding to a heat sink or the like becomes easy.

Next, a method for manufacturing the laser diode according to this embodiment will be described. First, as shown in FIG. 2A, for example, a CVD (Chemical Vapor Deposit) is formed on an n-type substrate 10 made of, for example, GaAs.
n) A silicon oxide film or a silicon nitride film is deposited by a method, or a layered semiconductor layer such as a Ga ₂ Se ₃ film is formed by another method, and is patterned to open a predetermined stripe region, thereby relaxing strain. The film 11 is formed.

Next, as shown in FIG.
By an epitaxial growth method such as an OCVD (metal organic chemical vapor deposition method), an Al film having a thickness of, for example, about 1500 nm is entirely formed on the n-type substrate 10 and the strain relaxation film 11 in a region where the strain relaxation film 11 is not provided. _0.4 Ga _0.6
An n-type cladding layer 12 made of As is formed.

Next, as shown in FIG. 2C, the n-type cladding layer 12 is formed by the same epitaxial growth method as described above.
An Al _0.3 Ga _0.7 A film having a thickness of, for example, about 10 nm is formed _thereon.
s first light guide layer 13 made of, for example, a quantum well made of Al _0.1 Ga _0.9 As having a thickness of about 10 nm and a multiple quantum well structure made up of a barrier layer made of Al _0.3 Ga _0.7 As having a thickness of about 10 nm, for example. (Oscillation wavelength 780n
m) Active layer 14, for example, Al having a thickness of about 10 nm
_A second optical guide layer 15 made of _0.3 Ga _0.7 As, for example, a p-type clad layer 16 made of Al _0.4 Ga _0.6 As and having a thickness of about 1200 nm, for example, a p-type contact layer 17 made of GaAs, are laminated.

In the subsequent steps, a part of the semiconductor laminate obtained in the above step except for a part to be a current injection region is removed from the surface of the p-type contact layer 17 to a depth in the middle of the p-type cladding layer 16. Then, the ridge portion is processed into a ridge shape in which the current injection region protrudes convexly, and the ridge portion is
The n-type current stop layer 18 is formed by embedding with doped n-type GaAs or the like, the p-electrode 19a and the n-electrode 19b are respectively formed, and the end face of the resonator is formed by cleavage or the like. I do.

According to the method of manufacturing a laser diode of the present embodiment, the n-type substrate and the semiconductor laminate have different physical properties such as the coefficient of thermal expansion. Even in this case, the strain can be relaxed by the strain relieving film formed at the interface between the n-type substrate and the semiconductor laminate, and a laser diode that can suppress the generation and growth of crystal dislocation can be manufactured. .

Second Embodiment The semiconductor light emitting device according to the present embodiment is a laser diode that oscillates laser light in the near infrared region such as the 780 nm band, as in the first embodiment. FIG. 3A is a perspective view illustrating a schematic configuration of the laser diode according to the present embodiment. For example, a strain relaxation film 21 is formed in one region on the p-type substrate 20. Further, the semiconductor laminate ST including the active layer 24 is formed on the p-type substrate 20 and the strain relaxation film 21 in a region where the strain relaxation film 21 is not provided. The p-type substrate 20 is made of, for example, GaAs.
s-based material, and the semiconductor laminate ST is made of AlGaAs.
It consists of system material. Further, the strain relaxation film 21 is a film substantially bonded by van der Waals force at least at an interface with the p-type substrate 20 or the semiconductor stack ST, such as a silicon oxide film or a silicon nitride film, or , And a layered semiconductor layer such as a Ga ₂ Se ₃ film.

FIG. 3B shows the laser diode of FIG.
FIG. 4 is a cross-sectional view showing a more detailed layer configuration of the card. That is, an example
For example, in one region on a p-type substrate 20 made of GaAs.
Thus, the strain relaxation film 21 is formed, and the strain relaxation film 2 is formed.
1 on the p-type substrate 20 in the region where the
And a film having a thickness of, for example, about 1500 nm
Al_0.4Ga_0.6 Example of a p-type cladding layer 22 made of As
For example, Al having a thickness of about 10 nm_{0. Three} Ga_0.7 From As
The first light guide layer 23, for example, A having a thickness of about 10 nm.
l _0.1 Ga_0.9 As quantum well of 10 nm
Al with moderate thickness_0.3 Ga _0.7 A barrier layer made of As
Of multiple quantum well structure (oscillation wavelength 780 nm) composed of
Layer 24, for example, Al having a thickness of about 10 nm_0.3 Ga
_0.7 The second light guide layer 25 made of As, for example, 1200
Al with a thickness of about nm_0.4 Ga_0.6 N-type ku consisting of As
Rad layer 26, for example, n-type contact made of GaAs
The layer 27 is laminated. As described above, the semiconductor product
A layer body ST is formed. In the above, the n-type semiconductor
Each of the layers is doped with, for example, Se,
Each of the conductor layers is doped with, for example, Zn.

Further, an n-electrode 28a such as AuGe / Ni / Au is formed so as to be connected to the n-type contact layer 27, while Ti is formed so as to be connected to the p-type substrate 20.
A p electrode 28b such as / Pt / Au is formed.

In the laser diode having the above-described structure, as in the first embodiment, the p-type substrate and the semiconductor laminate have different physical properties such as thermal expansion coefficients, and the heat generation when the laser diode is used as a laser diode. Even if the strain occurs, the strain can be relaxed by the strain relief film formed at the interface between the p-type substrate and the semiconductor laminated body by the same mechanism as described in the first embodiment, and the crystal dislocations Generation and proliferation can be suppressed.

Further, in the laser diode having the above configuration, the strain relaxation film 21 forms a stripe having a current confinement structure. Thus, when a predetermined voltage is applied to the n-electrode 28a and the p-electrode 28b, a current is injected while being constricted by the strain relaxation film 21, and the current is injected from the active layer 24 in the resonator direction D shown in FIG. A laser beam having a predetermined wavelength in the band is emitted.

The stripe width of the current relaxation structure is determined in accordance with the designed laser characteristics. The width x of the entire laser diode and the stripe width y of the strain relaxation film 21 are set so that, for example, y / x ≧ 0.3.

As described above, in the laser diode according to the present embodiment, the p-type substrate and the semiconductor laminate have different physical properties such as the coefficient of thermal expansion, and distortion occurs due to the difference in physical properties. Also, the strain can be relaxed by the strain relieving film formed at the interface between the p-type substrate and the semiconductor laminate, and the generation and growth of crystal dislocation can be suppressed. It is possible to improve the performance of a high-output laser diode or the like that has been particularly required in recent years.

Third Embodiment A semiconductor light emitting device according to the third embodiment has a thickness of, for example, 780 nm.
This is a laser array in which several tens of laser diodes having the same structure as that of the first embodiment for oscillating laser light in a near infrared region such as a band are integrated in parallel. FIG. 4A is a schematic view of a laser array according to the present embodiment, and FIG. 4B is a perspective view showing a schematic configuration of a portion corresponding to two laser diodes in the laser array. Common n-type substrate 1
In one region on zero, a strain relaxation film 11 is formed. Further, the same as in the first embodiment, including at least an n-type cladding layer, an active layer, and a p-type cladding layer on the n-type substrate 10 and the strain relaxation film 11 in a region where the strain relaxation film 11 is not provided. The semiconductor laminate ST having the structure
It is formed corresponding to each laser diode. The n-type substrate 10 is made of, for example, a GaAs-based material, and the semiconductor stacked body ST is made of an AlGaAs-based material. Further, the strain relaxation film 11 is a film substantially bonded by van der Waals force at least at an interface with the n-type substrate 10 or the semiconductor stacked body ST, such as a silicon oxide film or a silicon nitride film, or , G
It is a layered semiconductor layer such as an a ₂ Se ₃ film. Further, the semiconductor laminates ST to be each laser diode are separated by a groove G.

In the laser array according to the present embodiment, the light output can be increased to the watt class by integrating several tens of laser diodes, so that the heat generation becomes larger than that of the laser diode of the first embodiment. . For this reason,
Although the strain caused by the difference in thermal expansion coefficient between the n-type substrate 10 made of a GaAs-based material and each semiconductor stacked body ST made of an AlGaAs-based material is larger than that of the laser diode of the first embodiment, the description in the first embodiment will be given. By the same mechanism as described above, n
The strain can be relaxed by the strain relieving film formed at the interface between the mold substrate and each semiconductor laminate, and the generation and growth of crystal dislocation can be suppressed. Further, the strain caused by the difference in the thermal expansion coefficient can be reduced by employing a structure in which the semiconductor laminates ST constituting each laser diode are separated by the groove G.

As described above, in the laser array according to the present embodiment, the n-type substrate and the semiconductor laminate have different physical properties such as the thermal expansion coefficient, and distortion occurs due to the difference in physical properties. Also, the strain can be relaxed by the strain relieving film formed at the interface between the n-type substrate and the semiconductor laminate, and the generation and growth of crystal dislocation can be suppressed. It is possible to improve the performance of a laser array whose light output, which has been particularly required in recent years, has been increased to the watt class. Further, the amount of warpage of the laser array due to distortion during heat generation is reduced, and bonding to a heat sink or the like becomes easy.

Although the present invention has been described with reference to the three embodiments, the present invention is not limited to these embodiments. For example, the present invention is not limited to a semiconductor light emitting device such as a laser diode, and can be applied to all semiconductor devices having a configuration in which semiconductor regions having different physical properties such as thermal expansion coefficients are in contact with each other. In addition, when the present invention is applied to a semiconductor light emitting device including a plurality of light emitting elements, the present invention can be applied to light emitting elements having different emission wavelengths, elements having different emission intensities even when the emission wavelengths are the same, and light emitting elements having the same emission characteristics. Further, the present invention is also applicable to a semiconductor light emitting device having three or more semiconductor light emitting elements having different characteristics. Further, as a laser diode, it is also possible to apply to other lasers having various characteristics such as an index guide type and a pulsation laser. In addition, various changes can be made without departing from the spirit of the present invention.

[0047]

According to the semiconductor device of the present invention, the first semiconductor region and the first semiconductor region are partially formed at the interface between the first semiconductor region and the second semiconductor region having different predetermined physical properties. There is provided a strain relaxation film for relaxing strain caused by physical properties different from those of the two semiconductor regions, so that dislocation of crystals can be suppressed.

According to the semiconductor light emitting device of the present invention,
A semiconductor substrate and a semiconductor laminate have different physical properties such as a coefficient of thermal expansion, and a semiconductor in which at least a first cladding layer of a first conductivity type, a first active layer, and a second cladding layer of a second conductivity type are laminated. At a part of the interface with the stacked body, a strain relieving film for reducing strain caused by different physical properties of the semiconductor substrate and the semiconductor stacked body is provided, so that dislocation of crystals can be suppressed.

[Brief description of the drawings]

FIG. 1A is a perspective view showing a schematic configuration of a laser diode according to a first embodiment, and FIG.
It is sectional drawing which shows the more detailed layer structure of the laser diode of (a).

FIGS. 2A and 2B are cross-sectional views illustrating a manufacturing process of the laser diode manufacturing method according to the first embodiment, wherein FIG. 2A illustrates up to a process of forming a strain relaxation film, and FIG. (C) shows the steps up to the step of forming the semiconductor laminate.

FIG. 3A is a perspective view showing a schematic configuration of a laser diode according to a second embodiment, and FIG.
It is sectional drawing which shows the more detailed layer structure of the laser diode of (a).

FIG. 4A is a schematic view of a laser array according to a third embodiment, and FIG. 4B is a diagram illustrating a portion corresponding to two laser diodes in the laser array of FIG. 4A; It is a perspective view which shows a schematic structure.

FIG. 5A is a perspective view showing a schematic configuration of a laser diode according to a first conventional example, and FIG.
It is sectional drawing which shows the more detailed layer structure of the laser diode of (a).

FIG. 6A is a schematic view of a laser array according to a second conventional example, and FIG. 6B is a diagram of a portion corresponding to two laser diodes in the laser array of FIG. 6A. It is a perspective view which shows a schematic structure.

FIG. 7A is a view showing the state of FIG.
FIG. 7A is a schematic diagram illustrating a state in which the entire laser array is warped, and FIG. 7B is a schematic configuration diagram illustrating a state in which crystal dislocations are generated and propagated due to distortion due to heat generation.

[Explanation of symbols]

10 ... n-type substrate, 11 ... strain relaxation film, 12 ... n-type cladding layer, 13 ... first light guide layer, 14 ... active layer, 15 ... second light guide layer, 16 ... p-type cladding layer, 17 ... p-type contact layer, 18 ... n-type current blocking layer, 19a ... p-electrode, 19b ... n-electrode, 20 ... p-type substrate, 21 ... strain relaxation film, 22 ... p-type cladding layer, 23 ... first optical guide layer , 2
4 Active layer, 25 Second light guide layer, 26 N-type cladding layer, 27 N-type contact layer, 28a N-electrode, 28
b: p electrode, ST: semiconductor laminate, G: groove, T: crystal dislocation, R: light emission region.

Claims (15)

[Claims] A first semiconductor region, a strain relaxation film provided in one region on the first semiconductor region substrate, and a first semiconductor region in a region where the strain relaxation film is not provided.
A second semiconductor region provided on the semiconductor region and on the strain relaxation film, wherein the second semiconductor region has predetermined physical properties different from those of the first semiconductor region; and a difference between the first semiconductor region and the second semiconductor region. A semiconductor device having a configuration in which strain caused by physical properties is relaxed by the strain relaxation film. 2. The semiconductor device according to claim 1, wherein the first semiconductor region and the second semiconductor region have different thermal expansion coefficients as the different physical properties. 3. The semiconductor device according to claim 1, wherein the strain relaxation film is bonded at least at an interface with the first semiconductor region or the second semiconductor region by substantially van der Waals force. 4. The semiconductor device according to claim 1, wherein said strain relaxation film is a layered semiconductor layer. 5. A semiconductor substrate of a first conductivity type, a strain relief film provided in one region on the semiconductor substrate, and a semiconductor substrate and the strain relief film in a region where the strain relief film is not provided. A semiconductor laminate having at least a first cladding layer of a first conductivity type, a first active layer, and a second cladding layer of a second conductivity type, wherein the semiconductor substrate and the semiconductor laminate are A semiconductor light emitting device having different predetermined physical properties, wherein a distortion caused by different physical properties between the semiconductor substrate and the semiconductor laminate is reduced by the strain relief film. 6. The semiconductor substrate and the semiconductor laminate have different thermal expansion coefficients as the different physical properties.
The semiconductor light emitting device according to claim 1. 7. The semiconductor light emitting device according to claim 6, wherein said semiconductor substrate and said semiconductor laminate have substantially the same lattice constant. 8. The semiconductor light emitting device according to claim 5, wherein said semiconductor substrate and said semiconductor laminate are each a compound semiconductor region. 9. The semiconductor light emitting device according to claim 8, wherein said semiconductor substrate is made of a GaAs-based material, and said semiconductor laminated body region is made of an AlGaAs-based material. 10. The semiconductor light emitting device according to claim 5, wherein said strain relaxation film is bonded at least at an interface with said semiconductor substrate or said semiconductor laminate by substantially van der Waals force. 11. The semiconductor light emitting device according to claim 10, wherein said strain relaxation film is a silicon oxide film or a silicon nitride film. 12. The semiconductor light emitting device according to claim 5, wherein said strain relaxation film is a layered semiconductor layer. 13. The semiconductor light emitting device according to claim 12, wherein said strain relaxation film is a Ga ₂ Se ₃ film. 14. A plurality of semiconductor laminates each having at least a first cladding layer of a first conductivity type, a first active layer and a second cladding layer of a second conductivity type laminated on the semiconductor substrate. The semiconductor light emitting device according to claim 5, wherein each of the plurality of semiconductor laminates constitutes a semiconductor light emitting element. 15. A semiconductor device according to claim 14, wherein the plurality of semiconductor laminates are provided with a groove reaching the strain relief film or the semiconductor substrate between one semiconductor laminate and another semiconductor laminate. Semiconductor light emitting device.