JP2000091704A - Semiconductor device and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device suited to high-temperature operation in which the efficiency of carrier injection is improved and its manufacturing method. SOLUTION: A semiconductor laser 100 is provided with an optical waveguide 120. The optical waveguide 120 is formed by piling up in order a lower clad layer 130 made of n-InP, a core layer 140 and an upper clad layer 150 made of p-InP. The core layer 140 is formed by piling up in order a lower SCH layer 141 made of InGaAsP, a Hall stop layer, an active layer 145 made of AlInGaAs, an electron stop layer 147, and an upper SCH layer 149 made of InGaAs from the side of the lower clad layer 130. In this semiconductor laser 100, the optical loss in the core layer 140 can be reduced by forming the SHC layer (optical confinement layer) of InGaAsP which absorbs less light than AlInGaAs. Further, the efficiency of carrier injection to the active layer 145 can be improved by providing both Hall stop layer 143 and electron stop layer 147.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device and a method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, with the development of optical communication technology and optoelectronic technology, semiconductor lasers used as light source devices have been developed. Under these circumstances, a semiconductor laser formed on an InP (indium phosphide) substrate is usually used as a light source device in a wavelength region of 1.3 μm or 1.55 μm used in optical communication.

Conventionally, in a semiconductor laser formed on an InP substrate, the active layer is formed of InGaAsP (indium gallium arsenide phosphorus) / InGaAsP-QW (Quantum).
A well (quantum well) structure is generally used. However, the active layer having such a composition has a small electron-side band offset between the well layer and the barrier (barrier) layer. Therefore, particularly at the time of operation at a high temperature, there is a problem that electrons overflow from the active layer and carrier injection efficiency is reduced, thereby deteriorating laser characteristics.

[0004] Such a problem is described in CE Zah, R .;
B. Bhat, B .; Pathak, F .; Fabire,
W. Lin, M .; C. Andrewakis, D .;
M. Hwang, T .; P. Lee Z. Wang, D .;
Darby, D .; C. Flanders and J.M.
J. "High-performance" by Hsieh
uncool 1.3 μm AlxGayIn1-x-
yAs / InP strained-layer qu
antum well lasers forsubs
criber loop application "I
EEE Journal of Quantum Ele
ctoron. , Vol. 30, pp. 511-52
In the semiconductor laser disclosed in US Pat.
A tentative solution is being planned.

In this document, the active layer uses an AlGaInAs (aluminum gallium indium arsenide) / AlGaInAs-QW structure in which the band offset on the electron side is larger than the InGaAsP / InGaAsP-QW structure. According to this document, as a result of adopting such a configuration, the overflow of electrons from the quantum well is suppressed, and the laser characteristics in a high temperature state are improved.

[0006]

However, in the above-mentioned conventional document, the Al layer is formed outside the active layer having the QW structure.
SCH layer (Separa) made of GaInAs-based material
te Confinement Heterostru
cure; a light confinement layer). The following facts have been discovered by the inventors regarding such a configuration. That is, the AlGaInAs-based material has a very large light absorption (about 50 cm −1 in absorption coefficient larger than that of the InGaAsP-based material), and the magnitude of such absorption cannot sufficiently bring out the laser characteristics of the AlGaInAs-based material. Cause.

The SCH layer has a lower refractive index than the active layer and a higher refractive index than the cladding layer. Forming such an SCH layer in the core layer is particularly effective when the active layer is very thin compared to the optical wavelength and the QW having a weak light wave confinement effect is weak.
In a laser, it is effective to enhance the effect of confining light waves in the core layer.

As a result, conventionally, in a semiconductor device such as a QW laser, which generates and amplifies light by current injection, such as a QW laser, improvement of carrier injection efficiency into an active layer and suppression of optical loss in a core layer are simultaneously performed. It could not be established, and the performance of the device could not be sufficiently brought out.

The present invention has been made in view of the above-mentioned problems of the conventional semiconductor device, and suppresses light wave absorption in the core layer and overflow of carriers from the active layer to reduce optical loss. It is an object of the present invention to provide a new and improved semiconductor device that achieves both reduction and improvement of carrier injection efficiency.

[0010]

The above-mentioned problems of the conventional semiconductor device are as follows: an n-type cladding layer formed from an n-type semiconductor; a p-type cladding layer formed from a p-type semiconductor; an n-type cladding layer; This problem can be solved by employing the following configuration in a semiconductor device having an optical waveguide structure having a core layer interposed between the cladding layer and the core layer.

That is, as in the first aspect of the present invention, the core layer is formed of at least an active layer formed of an AlGaInAs-based material, and formed of InGaAsP interposed between the active layer and the n-type clad layer. The core layer comprises at least an active layer formed of an AlGaInAs-based material, and an active layer and a p-type clad layer formed of an AlGaInAs-based material. InG interposed between
and an optical waveguide layer formed of aAsP.

In the invention having the above-described structure, the active layer is formed of an AlGaInAs-based material. Therefore, particularly when the active layer has a quantum well structure, the band offset between the well layer and the barrier (barrier) layer becomes large, a deep well potential is formed in the active layer, and injected carriers overflow from the active layer. Probability of delivery decreases. In the invention according to claim 1 or 4, the optical waveguide layer corresponding to the SCH layer is made of InG.
It is formed from aAsP. InGaAsP is made of Al
Absorption is smaller than that of GaInAs-based material. Therefore, light loss in the core layer is reduced, and light generated and amplified in the active layer can be efficiently extracted outside the device.

As a result, according to the first or fourth aspect of the present invention, both reduction of optical loss and improvement of carrier injection efficiency are achieved, and laser characteristics and amplification characteristics are greatly improved. The invention described in claim 1 and the invention described in claim 4 exhibit synergistic effects when combined.

However, InGaAsP and AlGaInAs
With respect to the system material, InGaAsP has lower energy at the upper end of the conduction band. Therefore, in the first aspect of the present invention, electrons that are not captured in the active layer easily reach the optical waveguide layer due to the band offset effect, particularly during operation in a high temperature state such as room temperature operation. Also, InGaAsP
The energy difference between the lower end of the valence band and that of the AlGaInAs-based material is small. Therefore, in the invention described in claim 4, holes not caught in the active layer easily reach the optical waveguide layer. Such leakage of carriers from the active layer causes deterioration of light emission / amplification characteristics due to a decrease in carrier injection efficiency.

Therefore, in the core layer, the energy at the upper end of the valence band is lower than that of the optical waveguide layer by being interposed between the active layer and the optical waveguide layer. A structure including a potential barrier layer and a structure further including a potential barrier layer interposed between the active layer and the optical waveguide layer and having a higher energy at the lower end of the conduction band than the active layer, as in the invention according to claim 5. It is preferable to employ

In the second aspect, the potential barrier layer acts as a potential barrier for holes between the active layer and the optical waveguide layer. Therefore, particularly at the time of high-temperature operation, it is possible to suppress overflow of holes from the active layer to the optical waveguide layer, which is a problem in the first aspect. In the invention according to claim 5, the potential barrier layer acts as a potential barrier for electrons between the active layer and the optical waveguide layer. Therefore, the flow of electrons from the active layer to the optical waveguide layer, which is a problem in the fourth aspect, can be cut off.

As described above, according to the present invention, the probability that carriers injected into the active layer penetrate the active layer or overflow from the active layer is reduced.
Therefore, by reducing the carrier loss, it is possible to improve the emission / amplification characteristics themselves and prevent deterioration at high temperature operation. Needless to say, claim 2
When the invention described in (5) and the invention described in claim 5 are combined, a structure in which a potential barrier layer is inserted on both sides of the active layer is obtained.
A semiconductor device with further improved carrier injection efficiency can be provided.

Here, the potential barrier layer may be formed of, for example, n-InP as in the third aspect of the present invention, or may be formed of n-InP as in the sixth aspect of the present invention. ,
A configuration formed from p-AlInAs can be adopted.

The configuration of the invention described in each of the above-described claims exerts a great effect particularly in the configuration in which the active layer is a quantum well type active layer as in the invention of the seventh aspect. The quantum well structure is a fine structure that can artificially design and change electronic properties different from the intrinsic properties of the material, and is effective for improving the characteristics of the optical device. The active layer having such a quantum well structure includes a single quantum well (Single Quantum).
um Well; hereinafter, referred to as “SQW”. ) Multiplexing Quwan (Multiplexing Quan)
tun Well; hereinafter, referred to as “MQW”. ) The light wave confinement effect is weak because the structure is very thin.

Therefore, in a semiconductor device having a quantum well type active layer, the provision of the SCH layer often improves the light wave confinement by the refractive index structure.
Therefore, by forming the optical waveguide layer as an SCH layer and applying the inventions of the above-described claims 1 to 6, it is possible to reduce the absorption of light in the core layer and improve the efficiency of carrier injection into the active layer. Thus, it is possible to provide a high-performance semiconductor laser or optical amplifier suitable for high-temperature operation that has been achieved.

It is preferable that the optical waveguide structure has a stripe waveguide structure, as in the eighth aspect of the present invention. This is because the stripe waveguide can intensively inject current into the active layer, and thus can generate and amplify light more efficiently than the planar waveguide. Here, as the stripe waveguide, a buried hetero waveguide structure such as the structure of the invention according to claim 9 or a ridge waveguide structure such as the structure of the invention according to claim 10 is particularly applied. Is preferred.

In the semiconductor device according to the first to tenth aspects of the present invention, the first cladding layer formed of the first conductivity type semiconductor is formed as in the eleventh aspect of the present invention. A second step of forming a core layer laminated on the surface of the first clad layer, and a third step of forming a second clad layer composed of the second conductive type semiconductor and laminated on the surface of the core layer. A step of forming an optical waveguide layer made of InGaAsP, a step of forming an active layer made of an AlGaInAs-based material, and a step of forming an optical waveguide. Forming a potential barrier layer interposed between the layer and the active layer and serving as a potential barrier for either electrons or holes.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments when the present invention is applied to a semiconductor laser will be described below in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, components having the same functions and configurations are denoted by the same reference numerals, and redundant description is omitted.

First, the configuration of the semiconductor laser 100 according to the present embodiment will be described with reference to FIGS. Here, FIG. 1 is a sketch drawing showing a schematic configuration of the semiconductor laser 100. FIG. 2 shows a semiconductor laser 1.
It is explanatory drawing about the band structure of 00.

As shown in FIG. 1, a semiconductor laser 100 according to the present embodiment has a substrate 110 made of n-InP.
The one-chip laser element having an oscillation wavelength of, for example, about 1.3 μm formed thereon.

The semiconductor laser 100 has a ridge-type optical waveguide 120 in which an optical wave confinement effect is improved by an SCH structure (separation confinement heterostructure). In the semiconductor laser 100, the optical waveguide 120 is
The lower clad layer 130, the core layer 140, and the upper clad layer 150 are sequentially laminated. In the optical waveguide 120, the lower cladding layer 13 corresponding to the n-type cladding layer
Numeral 0 is formed from n-InP, and the upper cladding layer 150 corresponding to the p-type cladding layer is formed from p-InP.

The core layer 140 includes a lower SCH layer 141, a hole stop layer 143, an active layer 145, an electron stop layer 147, and an upper SCH layer 149 sequentially stacked from the lower clad layer 130 side to the upper clad layer 150 side. Configuration. As shown in FIG. 2, in the core layer 140, the active layer 145 includes an SQW in which a barrier layer 145a, a well layer 145b, and a barrier layer 145c are sequentially stacked from the hole stop layer 143 side to the electron stop layer 147 side.
(Single quantum well) structure. In the active layer 145, the well layer 145b is formed of, for example, AlGaInAs having a bandgap wavelength of about 1.4 μm to a thickness of the quantum theory level (extremely thin). On the other hand, the barrier layers 145a and 145c are, for example, about 1.0
It is formed from AlGaInAs having a band gap wavelength of μm to a thickness of a quantum theory level.

The lower SCH layer 1 corresponding to the optical waveguide layer
41 is formed of, for example, InGaAsP having a band gap wavelength of 1.2 to 1.0 μm so as to have a refractive index larger than that of the lower cladding layer 130. Further, the upper SCH layer 149 corresponding to another optical waveguide layer has an I-band having a band gap wavelength of, for example, 1.2 to 1.0 μm.
The upper cladding layer 150 is formed of nGaAsP so as to have a higher refractive index.

The light generated and amplified by the active layer 145 is supplied to the optical waveguide 120 by the lower cladding layer 130 and the lower SCH layer 1.
A refractive index structure (SCH structure) that causes total reflection is formed at the boundary between the upper cladding layer 41 and the upper cladding layer 150 and the upper SCH layer 149. In the optical waveguide 120, with such a configuration, the effect of confining the light wave in the core layer 140 is improved, and the propagation loss due to leakage can be reduced.

The lower SCH layer 141 and the upper SCH
The layer 149 is made of In which absorbs less than AlGaInAs.
It is formed of GaAsP. In the semiconductor laser 100 according to the present embodiment,
Light loss due to absorption in the core layer 140 is reduced.

In the semiconductor laser 100, the relationship between the band offset of the barrier layer 145a and the band offset of the lower SCH layer 141 is, for example, about 180 meV on the electron side (lower end of the conduction band) smaller on the electron side. On the hole side (upper end of the valence band), for example, the barrier layer 145a is smaller by about 70 meV. Similarly,
Regarding the band offset relationship between the barrier layer 145c and the upper SCH layer 149, from the viewpoint of energy, the SCH layer 149 is smaller on the electron side, for example, about 180 meV, and is smaller on the hole side, for example, about 70 meV. I have.

Further, the hole stop layer 143 corresponding to the potential barrier layer is made of n-InP,
It has a band structure in which the upper end of the valence band is on the lower energy side than the lower cladding layer 141 made of AsP. Further, the hole stop layer 143 is formed to have a thickness of, for example, 100 Å or more so as to prevent tunneling of holes. The electron stop layer 147 corresponding to another potential barrier layer is formed of p-AlInAs, and has a band structure in which the lower end of the conduction band is on the higher energy side than the barrier layer 145c of AlGaAsP.
Further, the electron stop layer 147 is formed with a thickness of, for example, 100 angstroms or more so that electrons do not tunnel.

Semiconductor laser 100 according to the present embodiment
In this case, the hole stop layer 143 and the electron stop layer 1
With 47, the probability that carriers (electrons and holes) in the active layer 145 leak from the active layer 145 can be greatly reduced.

As shown in FIG. 1 again, the semiconductor laser 100 according to the present embodiment further includes an n-type electrode 105, a contact layer 160, a p-type electrode 165, and a pad electrode 17.
0, an insulating film 180, and a buried layer 190 are provided.

The n-side electrode 105 is provided so as to cover the entire back surface of the substrate 110. The contact layer 160
P ⁺ -I so as to be laminated on the surface of the upper cladding layer 150.
It is made of nGaAs. In the semiconductor laser 100, the contact layer 160 and the upper cladding layer 150
Thus, a ridge stripe is formed. Furthermore, p
The side electrode 165 is provided so as to cover the surface of the contact layer 160.

The insulating film 180 is formed so as to cover the side surface of the ridge stripe composed of the contact layer 160 and the upper cladding layer 150 and the surface of the upper SCH layer 149 on the side of the stripe. In the semiconductor laser 100, the active layer 14 is formed by the insulating film 180 for element isolation.
5 is performed only through the ridge stripe composed of the contact layer 160 and the upper cladding layer 150. Further, the burying layer 190 is formed of polyimide so as to bury the side of the stripe composed of the contact layer 160 and the upper cladding layer 150.

The semiconductor laser 1 having the configuration described above
00 is merely an example of the semiconductor laser according to the present embodiment. For example, the oscillation wavelength of the semiconductor laser 100 is, for example, about 1.3 μm, but the present embodiment can be applied to a semiconductor laser having other various oscillation wavelengths, for example, 1.5 μm. In addition, the semiconductor laser 100
Is a ridge waveguide, but in the present embodiment, various other optical waveguides, for example, BH (Burie)
d Heterostructure (embedded hetero structure) The present invention can also be applied to semiconductor lasers such as waveguides, rib waveguides, and planar waveguides.

Further, the active layer 14 of the semiconductor laser 100
Reference numeral 5 denotes an SQW structure having a repetition number of 1. The present embodiment is directed to a semiconductor laser having an active layer such as an MQW structure having a repetition number of 2 or more, a strained QW structure, a bulk structure, or the like. It is also applicable to Furthermore, the SCH layer of the semiconductor laser 100 (the lower SCH layer 1)
41 and the upper SCH layer 149) have a band gap wavelength of 1.2 to 1.0 μm as an example, but this embodiment is applicable to a semiconductor laser having an SCH layer having various other band gap wavelengths. Can also be applied.

Next, a method of manufacturing the semiconductor laser 100 according to the present embodiment will be described with reference to FIGS. FIGS. 3 to 7 are explanatory views of each manufacturing process of the semiconductor laser 100. FIG.

In the method of manufacturing the semiconductor laser 100 described here, first, a lamination process shown in FIG. 3 is performed as a pre-stage of the laser process. In such a lamination process, MOVPE (Metal-Organic Vap) is used.
Each layer is sequentially formed by using crystal growth by a metal-organic vapor phase epitaxy (or phase epitaxy) method.

In the laminating step, first, the lower cladding layer 120 is formed by growing InP on the surface of the substrate 110 made of InP. Furthermore, InGaAsP (lower SCH layer 141) and n-In
P (hole stop layer 143), AlGaInAs (active layer 145), p-AlInAs (electron stop layer 147) and I
The nGaAsP (upper SCH layer 149) is sequentially crystal-grown to form the core layer 140. Furthermore, p-InP is crystal-grown on the surface of the core layer 140 to form the upper cladding layer 150. Further, the upper cladding layer 15
A contact layer 160 is formed by crystal growth of p ⁺ -InGaAs on the zero surface.

In this embodiment, the MOVP
In addition to the E method, for example, MBE (Molecular B
beam epitaxy method and CB
An E (Chemical Beam Epitaxy) method or the like can also be used.

Next, in the method of manufacturing the semiconductor laser 100, an etching mask forming step shown in FIG. 4 is performed.
In this etching mask forming step, the contact layer 1
60, for example, SiO ₂ (silicon dioxide) or SiN
A striped etching mask 200 having a width of 2 to 5 μm and made of a dielectric film such as (silicon nitride) is formed. still,
In FIG. 4, the etching mask 200 extends in a stripe shape in a direction perpendicular to the paper surface.

Next, a ridge stripe forming step shown in FIG. 5 is performed. In this step, the etching mask 200
The contact layer 160 and the upper cladding layer 150 are mesa-etched by dry etching or wet etching using GaN. As a result, in this step, a ridge stripe composed of the contact layer 160 and the upper clad layer 150 is formed.

Next, an embedding step shown in FIG. 6 is performed. In this step, first, the etching mask 200 (FIGS. 4 and 5) remaining on the surface of the contact layer 160 is removed. Next, after a dielectric film for element isolation is formed on the entire wafer surface, the dielectric film formed on the surface of the ridge stripe remaining in the mesa shape is removed, and an insulating film 180 is formed. Further, the side of the ridge stripe left in the mesa shape is buried with polyimide to protect the device, and a buried layer 190 is formed.

Next, in the manufacturing process of the semiconductor laser 100, an electrode forming process shown in FIG. 7 is performed. In this process,
A p-type electrode 165 is formed above the ridge stripe composed of the upper cladding layer 150 and the contact layer 160, and a pad electrode 170 is formed so as to cover the surface of the buried layer 190 and a part of the surface of the p-type electrode 165. further,
After polishing the back surface of the substrate 110, an n-type electrode 105 is formed on the back surface.

Next, current injection during operation of the semiconductor laser 100 according to this embodiment will be described with reference to FIGS. First, the semiconductor laser 100
In, the laser beam formed in the active layer 145 is
The light is propagated by being confined in the core layer 140 and output outside the semiconductor laser 100.

As shown in FIG.
In operation 00, a forward bias voltage is applied to the optical waveguide 120 from outside the semiconductor laser 100 via the electrode pad 170, the p-type electrode 165 and the n-type electrode 105, and current is injected into the active layer 145. . As shown in FIG. 2, current injection into the active layer 145 is performed by injection of electrons from the lower cladding layer 130 to the active layer 145 and injection of holes from the upper cladding layer 150 to the active layer 145. .

Electrons injected from the lower cladding layer 130 flow into the active layer 145 via the lower SCH layer 141 and the hole stop layer 143. Such electrons are prevented from moving to the upper SCH layer 149 by a potential barrier formed at the boundary between the active layer 145 and the electron stop layer 147. Therefore, in the optical waveguide 120, even when the electrons have a high energy such as an operation at room temperature (high temperature state), the leakage of the electrons from the active layer 145 to the upper SCH layer 149 is suppressed.

The holes injected from the upper clad layer 150 side are the upper SCH layer 149 and the electron stop layer 147.
Through the active layer 145. Such holes are prevented from moving to the lower SCH layer 141 by a potential barrier formed at the boundary between the active layer and the hole stop layer 143. Therefore, in the optical waveguide 120, the active layer 1
Overflow of holes from 45 to the lower SCH layer 141 is suppressed.

From the above, it can be seen that in the semiconductor laser 100 according to the present embodiment, carriers are efficiently injected into the active layer 145.

As described above, according to this embodiment, light loss in the device can be reduced by using InGaAsP for the SCH layer. Further, by providing the carrier stop layers on both sides of the active layer, it is possible to reduce leakage of carriers to the SCH layer. Therefore,
In the present embodiment, it is possible to provide a low threshold, high temperature operation laser.

The preferred embodiment according to the present invention has been described above, but the present invention is not limited to this configuration.
A person skilled in the art can envisage various modified examples and modified examples within the scope of the technical idea described in the claims, and these modified examples and modified examples are also included in the technical scope of the present invention. It is understood to be included.

For example, in the above embodiment, a semiconductor laser having no temperature control mechanism has been described as an example, but the present invention is not limited to such a configuration. The present invention can be applied to a semiconductor laser having a temperature control mechanism. In the semiconductor laser to which the present invention is applied, the oscillation efficiency does not easily decrease as the temperature increases. Therefore, normal oscillation operation can be ensured without having a temperature control mechanism. In addition, when a temperature control mechanism is provided, it is not necessary to operate the temperature control mechanism more than necessary.

In the above embodiment, the semiconductor laser emitting light inside the optical waveguide has been described as an example, but the present invention is not limited to this configuration. The present invention can be applied to other various semiconductor devices, for example, a semiconductor device to which a surface emitting laser, an optical amplifier, or the like is applied.

[0056]

According to the present invention, A is suitable for high-temperature operation.
1GaInAs-based material is used for the active layer. Furthermore, A
In order to cover the drawback that the absorption of the lGaInAs-based material is large, the optical waveguide layer has InGa with low light loss.
AsP is used. As a result, according to the present invention, it is possible to provide a semiconductor device capable of operating in a high temperature state without deteriorating device performance.

Further, in the present invention, the AlGaInAs-based material caused by the band offset
A potential barrier layer is provided to suppress the movement of carriers to GaAsP. Thus, the probability of carrier leakage from the active layer such as carrier overflow due to thermal energy in a high temperature state is reduced, and the efficiency of carrier injection into the active layer is improved. As a result, according to the present invention, leakage of carriers from the active layer is suppressed, and good laser oscillation and optical amplification with small optical loss can be realized.

[Brief description of the drawings]

FIG. 1 is a sketch drawing showing a schematic configuration of a semiconductor laser to which the present invention can be applied.

FIG. 2 is an explanatory diagram of a band structure of the semiconductor laser shown in FIG.

FIG. 3 is an explanatory view illustrating a method of manufacturing the semiconductor laser shown in FIG. 1;

FIG. 4 is another explanatory view of the method for manufacturing the semiconductor laser shown in FIG. 1;

FIG. 5 is another explanatory view of the method for manufacturing the semiconductor laser shown in FIG. 1;

FIG. 6 is another explanatory view of the method for manufacturing the semiconductor laser shown in FIG. 1;

FIG. 7 is another explanatory view of the method for manufacturing the semiconductor laser shown in FIG. 1;

[Explanation of symbols]

Reference Signs List 100 semiconductor laser 130 lower cladding layer 140 core layer 141 lower SCH layer 143 hole stop layer 145 active layer 147 electron stop layer 149 upper SCH layer 150 upper cladding layer Reference number = KT-0171
(1/15)

Continuation of the front page F term (reference) 5F041 AA03 AA32 CA04 CA05 CA34 CA39 5F073 AA13 AA45 AA51 AA73 AA74 CA15 EA23 EA29

Claims (11)

[Claims] 1. An n-type cladding layer formed from an n-type semiconductor, a p-type cladding layer formed from a p-type semiconductor, and a core layer interposed between the n-type cladding layer and the p-type cladding layer. Wherein the core layer is at least an active layer formed of a material based on aluminum gallium indium arsenide (AlGaInAs), and the active layer and the n-type cladding layer. And indium gallium arsenide (In)
An optical waveguide layer formed of GaAsP). 2. The method according to claim 1, wherein the core layer further includes a potential barrier layer interposed between the active layer and the optical waveguide layer, the potential barrier layer having a lower energy at the upper end of the valence band than the optical waveguide layer. The semiconductor device according to claim 1. 3. The device of claim 2, wherein the potential barrier layer is formed of n-type indium phosphide (InP).
3. The semiconductor device according to claim 1. 4. An n-type cladding layer formed from an n-type semiconductor, a p-type cladding layer formed from a p-type semiconductor, and a core layer interposed between the n-type cladding layer and the p-type cladding layer. Wherein the core layer comprises at least an active layer formed of an aluminum gallium indium arsenide (AlGaInAs) -based material; and the active layer and the p-type cladding layer. And indium gallium arsenide (In)
An optical waveguide layer formed of GaAsP). 5. The semiconductor according to claim 1, wherein the core layer further includes a potential barrier layer interposed between the active layer and the optical waveguide layer, the potential barrier layer having a lower conduction band energy than the active layer. apparatus. 6. The semiconductor device according to claim 5, wherein the potential barrier layer is made of p-type aluminum indium arsenide (p-AlInAs). 7. The active layer according to claim 1, wherein the active layer is a quantum well type active layer.
The semiconductor device according to any one of the above. 8. The optical waveguide structure according to claim 1, wherein said optical waveguide structure is a stripe waveguide structure.
8. The semiconductor device according to any one of 5, 6, and 7. 9. The semiconductor device according to claim 8, wherein said optical waveguide structure is a buried hetero waveguide structure. 10. The semiconductor device according to claim 8, wherein said optical waveguide structure is a ridge waveguide structure. 11. A first step of forming a first cladding layer made of a first conductivity type semiconductor, a second step of forming a core layer laminated on the surface of the first cladding layer, and Forming a second cladding layer made of a semiconductor of the second conductivity type and laminated on the surface of the core layer, the method comprising: forming a second cladding layer on the surface of the core layer; Forming an optical waveguide layer made of arsenic phosphorus (InGaAsP), forming an active layer made of an aluminum gallium indium arsenide (AlGaInAs) -based material, and interposing an intermediate layer between the optical waveguide layer and the active layer. Forming a potential barrier layer serving as a potential barrier for either electrons or holes.