JP3239943B2 - Manufacturing method of semiconductor laser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser used for optical communication and a method for manufacturing the semiconductor laser.
In particular, the present invention relates to a semiconductor laser capable of realizing a low threshold current and high uniformity, and a method of manufacturing the semiconductor laser.

[0002]

2. Description of the Related Art In recent years, optical communication has been spreading from a long-distance, large-capacity trunk system to an access system. Lasers for optical communication used in access systems are required to have low power consumption, that is, low threshold current, high efficiency, and low cost. It is necessary to improve the stay.

As a promising technique for realizing these, for example, an all-selection M as disclosed in JP-A-8-330665 is disclosed.
OVPE (Metal organic vapor)
phase epitaxy). In this method, a mesa including an active layer is formed in a region sandwiched between growth inhibition masks formed of two dielectric films,
The width of the active layer is determined by the opening width of the growth blocking mask. According to this method, the width of the active layer can be determined more accurately than the method of forming the active layer mesa by wet etching, which is effective in making the characteristics uniform. Further, since the band gap of the active layer can be controlled by the width of the growth prevention mask, it is suitable for manufacturing an optical integrated device.

FIGS. 17 to 2 show the conventional method.
0 will be described. As shown in FIG.
On the (001) plane of the P substrate 1, a pair of SiO ₂ films 2
110> direction. Next, n-type InP is grown by metal organic chemical vapor deposition (MOVPE).
Cladding layer 3 (carrier concentration 1 × 10 ¹⁸ cm ⁻³ , layer thickness 1
50 nm), InGaAsP guide layer (wavelength composition 1.1)
3 μm, lattice matched to InP, layer thickness 60 nm), InGa
AsP well layer (wavelength composition 1.29 μm, strain 0.7
%, A layer thickness of 5 nm) and an InGaAsP barrier layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 8 nm), a multiple quantum well active layer (well layer number: 7), InGaAs
Waveguide layer 4 composed of three layers of a P guide layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 60 nm), p-type I
An nP cladding layer 5 (carrier concentration 7 × 10 ¹⁷ cm ⁻³ , layer thickness 200 nm) is formed (FIG. 18).

Next, an SiO ₂ film 6 is formed on the top of the p-type InP cladding layer 5 and the p-type InP cladding layer 5 is formed by metal organic chemical vapor deposition.
-Type InP current blocking layer 7 (carrier concentration 6 × 10 ¹⁷ c
m ⁻³ , layer thickness 0.6 μm), n-type InP current blocking layer 8
(Carrier concentration: 3 × 10 ¹⁸ cm ⁻³ , layer thickness: 0.6 μm) (FIG. 19). After that, the SiO ₂ film 6 is removed,
A p-type InP cladding layer (carrier concentration 1 × 10 ¹⁸⁾
cm ^-3 , layer thickness 2 μm) 9, p-type InGaAs contact layer (carrier concentration 5 × 10 ¹⁸ cm ^-3 , layer thickness 0.3 μm)
Is formed (FIG. 20).

[0006] The semiconductor laser manufactured by the above method can control the waveguide width with high precision, so that the characteristics can be made highly uniform.

[0007]

However, a problem of the semiconductor laser manufactured by the conventional method is that the threshold current is high. The reason is that the layer thickness of the n-type current block layer 8 in the <111> direction (t in FIG. 21).
Is thin.

That is, both the p-type current block layer 7 and the n-type current block layer 8 have the (111) B plane and the (001)
Although it is composed of a plane called a plane, the InP (111)
Since the growth rate on the B-plane is much lower than the growth rate on the (001) plane, the n-type current blocking layer 8 is thick in the <001> direction as shown in FIG. 111
> Direction becomes very thin.

As a result of examining the correlation between the thickness of the n-type current block layer 8 in the <111> direction and the threshold current, FIG.
As shown in FIG. 2, it was found that the threshold current decreased as the layer thickness of the n-type current blocking layer 8 in the <111> direction increased. In FIG. 22, the vertical axis represents the threshold current (unit is milliampere (mA)), and the horizontal axis represents the thickness (unit is micrometer (μm)) of the n-type current block layer in the <111> direction. I have.

FIG. 22 shows that n <1
The layer thickness in the 11> direction needs to be at least 0.05 μm or more.
It is difficult to accurately control the layer thickness in the <111> direction.

The present invention has been made in view of such a situation, and a semiconductor laser having a low threshold current can be provided by forming the first conductive type current block layer to be thick in the <111> direction. That can be provided.

[0012]

A semiconductor according to claim 1.
The method of manufacturing a laser includes the steps of:
Activities formed using selective growth by metal vapor deposition
Mesa consisting of a double heterostructure including a sexual layer and the top of the mesa
Except for the part, at least formed by selective growth,
A semiconductor layer including a current blocking layer of the second conductivity type;
The first conductivity type current block formed on the current type current block layer
Over the entire surface of the mesa and the first conductivity type current blocking layer.
Having at least a second conductivity type cladding layer,
The interface between the cladding layer and the first conductivity type current blocking layer is
Of a semiconductor laser comprising a (001) plane and a (111) B plane
A method of manufacturing, wherein the growth of a second conductivity type current block layer is completed.
After completion, the growth of the second conductivity type current blocking layer is stopped,
The temperature is raised to the first reference temperature, and waits for a predetermined time.
A current blower of the second conductivity type consisting of the (01) plane and the (111) B plane
A first step of deforming the surface shape of the backing layer into a curved surface;
The temperature is lowered to the second reference temperature, and the first conductivity type current blocking layer is removed.
And a second step of forming. Claim
2. The method of manufacturing a semiconductor laser according to item 2.
Selective growth on metal substrate by metalorganic vapor phase epitaxy
Consists of a double heterostructure including an active layer formed by
Formed by selective growth on the mesa and the part except the top of the mesa
Half including at least the second conductivity type current blocking layer
A conductive layer, and a second conductive type current blocking layer formed on the second conductive type current blocking layer.
One conductivity type current blocking layer, mesa and first conductivity type current
At least a second conductivity type clad layer is formed on the entire surface of the block layer.
Having a second conductivity type cladding layer and a first conductivity type current block
The interface with the layer consists of the (001) plane and the (111) B plane
A method of manufacturing a semiconductor laser, comprising:
After the completion of the growth of the backing layer, the formation of the second conductivity type current blocking layer is performed.
Length and stop the group V source gas flow to the first reference flow
Increase, wait for a predetermined time, (001) plane and (1)
11) Surface shape of second-conductivity-type current block layer composed of surface B
First step of deforming the shape into a curved surface, and a group V source gas flow
Returning the flow rate to the second reference flow rate,
And forming a second step. Also,
V group material gas can be such that PH _3.
In the method for manufacturing a semiconductor laser according to the present invention, the second conductive
After the completion of the growth of the current block layer of the second conductivity type,
The growth of the backing layer is stopped, and the temperature is raised to the first reference temperature.
Wait for a certain amount of time and check whether the (001) plane and the (111) B plane
Surface of the second conductivity type current block layer made of
A first step of deforming, and cooling to a second reference temperature;
A second step of forming a one conductivity type current block layer.
No. Alternatively, after completion of the growth of the second conductivity type current block layer.
Then, the growth of the second conductivity type current blocking layer is stopped,
Increase the source gas flow rate to the first reference flow rate and
Wait for a while and consist of (001) plane and (111) B plane
The surface shape of the current block layer of the second conductivity type is changed to a curved surface.
A first step of causing the group V source gas flow to a second reference flow rate
And forming a first conductivity type current block layer in the second step
And

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to FIGS.

(First Embodiment) FIGS. 1 to 10 show a method of manufacturing a semiconductor laser according to the present invention.
FIG. 2 is a block diagram illustrating a configuration example of a semiconductor laser manufactured according to the first embodiment. As shown in FIG.
In the embodiment, a pair of dielectric films (SiO ₂ films) 2 are formed in a stripe shape in the <110> direction on the (001) plane of a first conductivity type semiconductor substrate (n-type InP substrate) 1. (FIG. 1). Next, the first conductivity type clad layer 3, the waveguide layer 4 including the guide layer and the active layer 4, and the second conductivity type clad layer 5 are formed by metal organic chemical vapor deposition (FIG. 2).
Next, after a dielectric film 6 is formed on the top of the second conductivity type clad layer 5, a semiconductor layer including at least the second conductivity type current blocking layer 7 is formed by metal organic chemical vapor deposition. At this time, the surface of the second conductivity type current blocking layer 7
It is composed of a (001) plane and a (111) B plane (FIG. 3).

Next, the current blocking layer 7 of the second conductivity type is
Is stopped, and the temperature is made higher than the normal growth temperature of the current blocking layer. During this time, the surface of the second conductivity type current blocking layer 7 is deformed into a curved surface by mass transport (FIG. 4). Thereafter, the temperature is lowered to the normal growth temperature of the current block layer, and the first conductivity type current block layer 8 is grown, as shown in FIG.
The interface between the first conductive type current blocking layer 8 and the first conductive type current blocking layer 8 is a curved surface,
In addition, the surface of the first conductivity type current blocking layer 8 has a (001) plane and a (111) B plane.

Thereafter, the dielectric film 6 is removed, and a second conductivity type cladding layer 9 and a second conductivity type contact layer 10 are formed by metal organic chemical vapor deposition. According to this method, the interface between the second-conductivity-type current block layer 7 and the first-conductivity-type current block layer 8 has a curved surface, and the thickness of the first-conductivity-type current block layer 8 in the <111> direction is 0.05 μm. As described above, a semiconductor laser thicker than that of the conventional structure is manufactured (FIG. 6).

In the semiconductor laser manufactured by the method described in the first embodiment, the thickness (t in FIG. 7) of the first conductivity type current block layer 8 in the <111> direction is set to 0.05.
Since the thickness can be increased to μm or more, the leakage current and the threshold current can be reduced as compared with a semiconductor laser having a conventional structure.

(First Example) Next, a first example of the first embodiment of the present invention will be described in detail with reference to FIG.

On the (001) plane of the n-type InP substrate 1, 1
A pair of SiO ₂ films 2 are formed in a stripe shape in the <110> direction (FIG. 1). The width of the SiO ₂ film 2 is 5 μm, and the opening width is 1.5 μm. Next, by metal organic chemical vapor deposition,
n-type InP cladding layer 3 (carrier concentration 1 × 10 ¹⁸ cm
^-3 , layer thickness 150 nm), InGaAsP guide layer (wavelength composition 1.13 μm, lattice matching with InP, layer thickness 60 n)
m), InGaAsP well layer (wavelength composition 1.29 μm)
m, strain 0.7%, layer thickness 5 nm) and an InGaAsP barrier layer (wavelength composition 1.13 μm, lattice matching to InP, layer thickness 8 nm), a multiple quantum well active layer (well layer number: 7), InGaAsP guide layer (Wavelength composition 1.13μ
a waveguide layer 4 composed of three layers, lattice matched to m and InP, having a layer thickness of 60 nm, and a p-type InP clad layer 5 (carrier concentration 7).
× 10 ¹⁷ cm ^-3 , thickness 200 nm) (FIG. 2).

Next, on the top of the p-type InP cladding layer 5, S
An iO ₂ film 6 is formed, and a p-type InP current blocking layer 7 (carrier concentration of 6 × 10 ¹⁷ cm) is formed by metal organic chemical vapor deposition.
^-3 , layer thickness 0.6 μm) under the conditions of a growth temperature of 575 ° C., a growth pressure of 760 Torr, a flow rate of trimethylindium (TMIn) of 770 cc / sec (min), and a flow rate of phosphine (PH ₃ ) of 250 cc / min. At this time, p
The surface of the type InP current block layer 7 is composed of a (001) plane and a (111) B plane (FIG. 3).

Next, the supply of trimethylindium is stopped, and the growth of the p-type InP current blocking layer 7 is stopped.
The temperature is raised to 625 ° C. and waits for 5 minutes. Then
The surface of the p-type InP current block layer 7 composed of the (001) plane and the (111) B plane changes to a curved surface due to enhanced mass transport (FIG. 4). Thereafter, the temperature is returned to 575 ° C., growth is restarted by supplying trimethylindium, and an n-type InP current blocking layer 8 (carrier concentration 3 × 10 ¹⁸ cm ⁻³ , layer thickness 0.6 μm) is formed (FIG. 5). ).

Thereafter, the SiO ₂ film 6 is removed, and p
Type InP cladding layer 9 (carrier concentration 1 × 10 ¹⁸ c
m ⁻³ , layer thickness 2 μm), p-type InGaAs contact layer 1
0 (carrier concentration 5 × 10 ¹⁸ cm ^-3 , layer thickness 0.3 μm)
Is formed (FIG. 6).

(Second Embodiment) Next, a second embodiment according to the first embodiment of the present invention will be described in detail with reference to FIGS. 8 to 10 using a spot size converter integrated laser as an example. explain.

On the (001) plane of the n-type InP substrate 1, 1
A pair of SiO ₂ films 12 are formed in a stripe shape in the <110> direction (FIG. 8). The width of the SiO ₂ film 12 is 25 μm in the laser part, and changes from 25 μm to 5 μm in the spot size conversion part. The opening width of the SiO ₂ film 12 is 1.5 μm, the length of the laser section is 300 μm, and the length of the spot size conversion section is 200 μm.

Next, the n-type I
nP cladding layer 13 (carrier concentration 1 × 10 ¹⁸ cm ⁻³ ,
InGaAsP guide layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 60 nm), I
nGaAsP well layer (wavelength composition 1.29 μm, strain 0.7%, layer thickness 5 nm) and InGaAsP barrier layer (wavelength composition 1.13 μm, lattice matching to InP, layer thickness 8 nm)
Quantum well active layer (7 well layers) made of InG
a waveguide layer 14 composed of three layers of an aAsP guide layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 60 nm)
p-type InP cladding layer 15 (carrier concentration 7 × 10 ¹⁷ c
m ⁻³ , thickness 200 nm) (FIG. 9).

The composition, the amount of strain, and the layer thickness are all values in the laser portion. In the spot size conversion portion, as the mask width (the width of the SiO ₂ film 12) decreases,
The thickness of the waveguide layer 14 is reduced to about 1/3. Thereafter, an SiO ₂ film 16 is formed on the top of the p-type InP cladding layer 15.
(FIG. 10), and a current blocking layer, a cladding layer, and a contact layer are formed in the same manner as in the first embodiment.

In the spot size converter integrated laser manufactured as described above, the confinement of light is weakened due to the decrease in the thickness of the waveguide layer in the spot size conversion section. And good coupling efficiency with an optical fiber can be obtained without a lens. By applying the present invention to a device in which such a semiconductor laser and other functions are integrated, the threshold current can be reduced.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
The embodiment will be described in detail with reference to FIGS.

On the (001) plane of the first conductivity type semiconductor substrate 1, a pair of dielectric films 2 are formed in stripes in the <110> direction (FIG. 1). Next, a first conductivity type cladding layer 3, a waveguide layer 4 composed of a guide layer and an active layer, and a second conductivity type cladding layer 5 are formed by metal organic chemical vapor deposition (FIG. 2). Next, after forming the dielectric film 6 on the top of the second conductivity type clad layer 5, at least the second conductivity type current blocking layer 7 is formed by metal organic chemical vapor deposition. At this time, the surface of the second conductivity type current block layer 7 is (001)
It comprises a plane and a (111) B plane (FIG. 3).

Next, the current blocking layer 7 of the second conductivity type is
Is stopped and the flow rate of the group V source gas is increased. During this time, the surface of the second conductivity type current blocking layer 7 is deformed into a curved surface by mass transport (FIG. 4). Thereafter, the flow rate is returned to the normal group V source gas, and the first conductivity type current block layer 8 is grown, as shown in FIG.
Conductive current block layer 7 and first conductive current block layer 8
Is a curved surface, and the surface of the first-conductivity-type current block layer 8 has a (001) plane and a (111) B plane.

Thereafter, the dielectric film 6 is removed, and a second conductivity type cladding layer 9 and a second conductivity type contact layer 10 are formed by metal organic chemical vapor deposition. By this method, FIG.
As shown in (1), the interface between the second conductivity type current blocking layer 7 and the first conductivity type current blocking layer 8 is formed of a curved surface,
The layer thickness of the conductive type current block layer 8 in the <111> direction is set to 0.
It is possible to manufacture a semiconductor laser having a thickness of not less than 05 μm as compared with the conventional structure.

The semiconductor laser manufactured by the method described in the above embodiment has a structure in which the current blocking layer 8 of the first conductivity type is
The thickness in the 111> direction (t in FIG. 7) is 0.05 μm
Since the thickness can be increased as described above, the leakage current can be reduced and the threshold current can be reduced as compared with the semiconductor laser having the conventional structure.

(Example) Next, an example according to the second embodiment of the present invention will be described in detail with reference to FIGS.

On the (001) plane of the p-type InP substrate 31,
A pair of SiO ₂ films 32 are formed in a stripe shape in the <110> direction (FIG. 11). The width of the SiO ₂ film 32 is 5 μm.
m, and the opening width is 1.5 μm.

Next, p-type I
nP cladding layer 33 (carrier concentration 7 × 10 ¹⁷ cm ⁻³ ,
InGaAsP guide layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 60 nm), I
nGaAsP well layer (wavelength composition 1.29 μm, strain 0.7%, layer thickness 5 nm) and InGaAsP barrier layer (wavelength composition 1.13 μm, lattice matching to InP, layer thickness 8 nm)
Quantum well active layer (7 well layers) made of InG
a waveguide layer 34 composed of three layers of an aAsP guide layer (wavelength composition: 1.13 μm, lattice matching to InP, layer thickness: 60 nm);
n-type InP cladding layer 35 (carrier concentration 1 × 10 ¹⁸ c
m ⁻³ , thickness 200 nm) (FIG. 12).

Next, an SiO ₂ film 36 is formed on the top of the n-type InP cladding layer 35 and is formed by metal organic chemical vapor deposition.
p-type InP current blocking layer 37 (carrier concentration 6 × 10
¹⁷ cm ⁻³ , layer thickness 0.2 μm), n-type InP current blocking layer 38 (carrier concentration 1 × 10 ¹⁸ cm ⁻³ , layer thickness 0.4 μm)
m), the growth temperature is 625 ° C., the growth pressure is 760 Torr,
Trimethylindium flow rate 770cc / min, PH ₃
It is grown under the condition of a flow rate of 60 cc / min. At this time,
The surface of the n-type InP current block layer 38 has a (001) plane and a (111) B plane (FIG. 13).

Next, the supply of trimethylindium was stopped, the growth was stopped, and the PH ₃ flow rate was set to 250 cc / mi.
n and wait 5 minutes. Then (001)
The surface of the n-type InP current blocking layer 38 composed of the (111) B plane and the (111) B plane changes into a curved surface due to the promotion of mass transport (FIG. 14). Thereafter, the PH ₃ flow rate was returned to 60 cc / min, and the p-type InP current blocking layer 39 (carrier concentration 1 × 10 ¹⁸ cm ⁻³ , layer thickness 0.6 μm)
m) (FIG. 15).

Thereafter, the SiO ₂ film 36 is removed, and the n-type InP cladding layer 40 (carrier concentration 3 × 10 ¹⁸ c) is formed on the entire surface.
m ⁻³ , a layer thickness of 2 μm) (FIG. 16).

With such a configuration, the same effect as in the above embodiment can be obtained.

As described above, in each of the above embodiments, a reduction in threshold current can be realized. The reason is that the <111>
This is because the leakage current can be reduced because the thickness in the direction> 0.05 μm or more, which is thicker than the conventional structure.

In the first example of the first embodiment, since the thickness of the n-type current block layer in the <111> direction can be accurately controlled, the threshold current at 25 ° C. In contrast to the conventional semiconductor laser of 5.3 mA, the semiconductor laser in which the thickness of the n-type current block layer in the <111> direction is 0.05 μm is 4.8 mA and 0.12 μm. In a semiconductor laser, the current can be reduced to 4.2 mA, and the reproducibility and uniformity can be improved.

As described above, in the above embodiment, the interface between the second conductivity type current block layer 7 and the first conductivity type current block layer 8 is curved, and the first conductivity type current block layer 8 is The interface with the second conductivity type cladding layer 9 is (00
Since it can be composed of the 1) plane and the (111) B plane, the layer thickness of the first conductivity type current blocking layer 8 in the <111> direction can be made larger than that of the conventional structure.
As a result, the leakage current can be reduced and the threshold current can be reduced.

The specific numerical values used in each of the above embodiments are examples, and the present invention is not limited to these numerical values.

[0044]

As described above, the production of the semiconductor laser of the present invention is described.
According to the fabrication method, the growth of the second conductivity type current block layer is completed.
Later, the growth of the second conductivity type current blocking layer is stopped,
1 and then wait for a predetermined time,
A current block of the second conductivity type including the 1) plane and the (111) B plane.
A first step of deforming the surface shape of the work layer into a curved surface;
2 to form a first conductivity type current blocking layer.
And a second step. Alternatively, the current of the second conductivity type
After completion of the growth of the block layer, the second conductivity type current block layer
Is stopped and the flow rate of the group V source gas is reduced to the first reference flow rate.
And wait for a predetermined time until the (001) plane
Table of the second conductivity type current block layer composed of the (111) B plane
A first step of deforming the surface shape into a curved surface;
The flow rate is returned to the second reference flow rate.
And a second step of forming a mask layer .
The layer thickness of the conductivity type current block layer in the <111> direction can be set to a predetermined reference value, for example, 0.05 μm or more, and can be made thicker than that of the conventional structure, so that the leakage current is reduced and the threshold is reduced. The value current can be reduced. In addition, power consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

FIG. 2 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

FIG. 4 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

FIG. 5 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a first embodiment, a first example, and a second embodiment of the present invention.

7 is a diagram showing a thickness of a first conductivity type current blocking layer in the <111> direction in the embodiment of FIG. 6;

FIG. 8 is a diagram illustrating a second example of the first embodiment of the present invention.

FIG. 9 is a diagram illustrating a second example of the first embodiment of the present invention.

FIG. 10 is a diagram illustrating a second example of the first embodiment of the present invention.

FIG. 11 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 12 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 13 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 14 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 15 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 16 is a diagram illustrating an example of the second embodiment of the present invention.

FIG. 17 is a diagram illustrating a conventional method of manufacturing a semiconductor laser.

FIG. 18 is a diagram illustrating a conventional method for manufacturing a semiconductor laser.

FIG. 19 is a diagram illustrating a conventional method of manufacturing a semiconductor laser.

FIG. 20 is a diagram illustrating a conventional method of manufacturing a semiconductor laser.

FIG. 21 is a diagram showing a thickness of a first conductivity type current blocking layer of a conventional semiconductor laser in a <111> direction.

FIG. 22 shows the relationship <11 in the n-type current block layer of the semiconductor laser.
1 is a graph showing a relationship between a thickness in a 1> direction and a threshold current.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 First conductivity type semiconductor substrate (n-type InP substrate) 2,12 Dielectric film (SiO ₂ film) 3,13 First conductivity type clad layer (n-type InP clad layer) 4,14 Waveguide layer (InGaAsP waveguide) 5, 15 Second conductivity type cladding layer (p-type InP cladding layer) 6, 16 Dielectric film (SiO ₂ film) 7 Second conductivity type current blocking layer (p-type InP current blocking layer) 8 First conductivity type Current block layer (n-type InP current block layer) 9 Second conductivity type cladding layer (p-type InP cladding layer) 10 Second conductivity type contact layer (p-type InGaAs contact layer) 31 p-type InP substrate 32 SiO ₂ film 33 p -type InP cladding layer 34 InGaAsP waveguide layer 35 n-type InP cladding layer 36 SiO ₂ layer 37 p-type InP current blocking layer 38 n-type InP current blocking layer 39 p-type I P current blocking layer 40 n-type InP cladding layer

Claims (3)

(57) [Claims] An organic metal vapor is deposited on a first conductivity type semiconductor substrate.
The active layer formed by selective growth is grown by the phase growth method.
A mesa consisting of a double heterostructure including the top of the mesa
Excluding at least the portion formed by selective growth
A semiconductor layer including a second conductivity type current blocking layer;
A first conductive type current block formed on the conductive type current block layer;
A lock layer, the mesa and the first conductivity type current block.
Having at least a second conductivity type clad layer on the entire surface of the magnetic layer,
The second conductivity type cladding layer and the first conductivity type current block
The interface with the magnetic layer consists of the (001) plane and the (111) B plane.
A method of manufacturing a semiconductor laser , comprising:
Stopping the growth of the two-conductivity type current blocking layer, the first reference
The temperature is raised to the temperature, and waits for a predetermined time.
(111) The current block layer of the second conductivity type comprising a B surface
A first step of deforming a surface shape of the current block into a curved shape, and cooling the first conductivity type current block to a second reference temperature.
Semiconductors, characterized in that it comprises a second step of forming a layer
Manufacturing method of body laser. 2. The method according to claim 1, wherein the first conductive type semiconductor substrate has an organic metal
The active layer formed by selective growth is grown by the phase growth method.
A mesa consisting of a double heterostructure including the top of the mesa
Excluding at least the portion formed by selective growth
A semiconductor layer including a second conductivity type current blocking layer;
A first conductive type current block formed on the conductive type current block layer;
A lock layer, the mesa and the first conductivity type current block.
Having at least a second conductivity type clad layer on the entire surface of the magnetic layer,
The second conductivity type cladding layer and the first conductivity type current block
The interface with the magnetic layer consists of the (001) plane and the (111) B plane.
A method of manufacturing a semiconductor laser , comprising:
The growth of the two-conductivity type current block layer is stopped, and
Increase the flow rate to the first reference flow rate for a predetermined time
Waits for the (001) plane and the (111) B plane,
Deform the surface shape of the two-conductivity type current block layer into a curved surface
A first step of returning the group V source gas flow rate to a second reference flow rate;
This and a second step of forming a first conductivity type current blocking layer
And a method for manufacturing a semiconductor laser. Wherein the group V source gas that is PH ₃
3. The method for manufacturing a semiconductor laser according to claim 2, wherein: