JP2001230491A - Semiconductor laser element and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor laser element that can more easily reduce a drive current and a drive voltage at a high output with excellent long term reliability by intentionally using a film with a high stress for a film providing void atoms in the case of forming a window structure of the semiconductor laser element through disordering, and to provide its manufacturing method. SOLUTION: In the case of manufacturing a semiconductor laser element consisting of a layer structure including a lower clad layer, an active layer and an upper clad layer on a substrate by using a chemical semiconductor containing at least gallium, after forming a SixOyNz (x, y, z are 1 or over. Hereinafter the same holds) to an upper part of the layer structure in the vicinity of an area acting like an end face of a laser resonator, annealing is conducted to generate voids under the SixOyNz, the voids are diffused up to the active layer so as to disorder the active layer in the vicinity of the area acting like the end face of the laser resonator.

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 an optical disk or the like and a method of manufacturing the same, and more particularly to a semiconductor laser having a window structure excellent in high output operation characteristics and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, various semiconductor lasers have been widely used as light sources for optical disk devices. Above all,
The high-output 780 nm band AlGaAs semiconductor laser has an M
It is used as a light source for writing on discs such as D players and CD-R drives, and higher output is strongly required.

One of the factors limiting the increase in the output of a semiconductor laser is optical damage (COD; Catas) caused by an increase in the optical output density in the active layer region near the light emitting end face.
(Tropic Optical Damage).

[0004] The cause of the COD is that the active layer region near the light emitting end face is an absorption region for laser light. At the light emitting end face, there are many non-radiative recombination centers called surface states or interface states. Since the carriers injected into the active layer near the light emitting end face are lost by the non-radiative recombination, the injected carrier density of the active layer near the light emitting end face is lower than that at the center. As a result, the active layer region near the light emitting end face becomes an absorption region for the wavelength of the laser light generated by the high injected carrier density at the center.

[0005] As the light output density increases, local heat generation in the absorption region increases, the temperature rises, and the band gap energy decreases. As a result, a positive feedback that the absorption coefficient further increases and the temperature rises is applied, and the temperature of the absorption region near the light emitting end surface finally reaches the melting point,
D occurs.

To improve the COD level, one method of increasing the output of a semiconductor laser is disclosed in JP-A-9-23.
No. 037, a method utilizing a window structure by disordering of a multiple quantum well structure active layer has been employed.

FIG. 13 shows a structure diagram of a semiconductor laser device disclosed in Japanese Patent Application Laid-Open No. 9-23037 as a prior art of a semiconductor laser having this window structure.

In FIG. 13, (a) is a perspective view including a light emitting end face, (b) is a cross-sectional view of the waveguide taken along the line Ia-Ia 'in FIG. (A), and (c) is Ib in FIG. It is sectional drawing of the layer thickness direction in the -Ib 'line. In FIG. 13, 10
01 is a GaAs substrate, 1002 is an n-type AlGaAs lower cladding layer, 1003 is a quantum well active layer, 1004a is a p-type AlGaAs first upper cladding layer, and 1004b is a p-type AlG
aAs second upper cladding layer, 1005 is a p-type GaAs contact layer, 1006 (shaded portion) is a vacancy diffusion region, 1007
(Shaded area) is a proton injection region, 1008 is an n-side electrode, 1
009 is a p-side electrode, 1020 laser resonator end face, 100
Reference numeral 3a denotes a region of the quantum well active layer 1003 which contributes to laser oscillation, and reference numeral 1003b denotes a window structure region formed in the vicinity of the laser resonator end face 1020 of the quantum well active layer 1003.

Next, a conventional method of manufacturing a semiconductor laser device will be described with reference to a process chart shown in FIG. n-type GaAs
An n-type AlGaAs lower cladding layer 100 is formed on a substrate 1001.
2. A quantum well active layer 1003 and a p-type AlGaAs first upper cladding layer 1004a are sequentially epitaxially grown (FIG. 14A). Next, an SiO ₂ film 1010 is formed on the surface of the p-type AlGaAs first upper cladding layer 1004a, and a stripe-shaped opening 1010a extending in the laser resonator direction and having a length not reaching the laser resonator end face is formed (FIG. 14 (b)). Next, the wafer is placed in an As atmosphere at 800
When annealing is performed at a temperature equal to or higher than ° C., Ga atoms are absorbed from the surface of the p-type AlGaAs first upper cladding layer 1004a in contact with the SiO ₂ film 1010, and Ga vacancies are generated in the p-type AlGaAs first upper cladding layer 1004a. The holes diffuse until reaching the quantum well layer active layer 1003 inside the crystal, thereby disordering the quantum well layer structure. In the disordered active layer region, the effective band gap widens, so that it functions as a window transparent to the oscillating laser light.

Further, the SiO ₂ film 1010 is removed, and p
P-type AlGaAs on the first upper cladding layer 1004a
A GaAs second upper cladding layer 1004b and a p-type GaAs contact layer 1005 are sequentially grown epitaxially.
(FIG. 14 (c)). Next, the p-type GaAs contact layer 10
A resist film is formed on the 05, the resist 1 in stripes same region as the opening 1010a of the stripe of the SiO ₂ film 1010 by photolithography
011 is formed. Next, this striped resist 1
011 as a mask, p-type GaAs contact layer 100
5 is implanted from the surface side to form a high-resistance region 1007 to be a current blocking layer. (FIG. 14
(D)). Finally, the n-side electrode 1 is placed on the GaAs substrate 1001 side.
008, a p-side electrode 1009 is formed on the p-type GaAs contact layer 1005, and the wafer is cleaved to obtain the semiconductor laser device of FIG.

[0011]

Disordered region formed in the vicinity of the light emitting facet of the invention Problems to be Solved conventional window structure semiconductor laser device, so as to be larger than the band gap energy corresponding to the lasing wavelength, SiO ₂ film 1010 To the p-type AlGaAs first upper cladding layer 1004a in contact with
Vacancy generation and Ga in the quantum well layer active layer 1003
It is formed by diffusing vacancies.

However, in the above-described conventional method using the SiO ₂ film, in order to make the band gap energy of the active layer near the light emitting end face larger than the band gap energy corresponding to the laser oscillation wavelength, it is necessary to use a high temperature. It is necessary to make the annealing time longer.

As a result, impurities such as Zn atoms present in each layer having p-type conductivity are removed from the quantum well layer active layer 1003.
As a result, the driving current and the driving voltage at the time of high output are increased, and the long-term reliability is reduced.

If the annealing temperature is lowered or the annealing time is shortened, the quantum well layer active layer 10
03 can suppress the diffusion of impurities such as Zn atoms, but the generation of vacancy atoms and the diffusion of vacancy atoms into the quantum well layer active layer 1003 become insufficient. Absorb.

As a result, COD is likely to occur in the active layer region near the light emitting end face, causing a decrease in the maximum light output at the time of high output driving, and failing to provide sufficient long-term reliability.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and when a window structure of a semiconductor laser device is formed by disordering, a film for giving vacancy atoms is intentionally subjected to a higher stress. It is an object of the present invention to provide a semiconductor laser device which can easily reduce a driving current and a driving voltage at the time of high output by using a high film, and is excellent in long-term reliability, and a manufacturing method thereof. is there.

[0017]

According to a method of manufacturing a semiconductor laser device according to the present invention, a laminated structure including a lower cladding layer, an active layer, and an upper cladding layer on a substrate using at least a compound semiconductor containing gallium. When manufacturing a semiconductor laser device composed of: a SixOyNz film (x, y and z are 1 to 1) above the laminated structure in the vicinity of a region to be an end face of a laser cavity.
that's all. The same applies hereinafter. ) Is formed, annealing is performed to generate holes under the SixOyNz film, and the holes are diffused until reaching the active layer, whereby the active layer in the vicinity of the laser cavity facet is formed. The above-mentioned object is achieved by disordering.

[0018] Here, the Si _x O _y N _z film, a sputtering method, preferably formed by any one of a plasma CVD method. This is because in the formation of Si _x O _y N _z film, is generated vacancies atoms by plasma damage to the wafer surface is epitaxially grown, effectively effective active layer near the light-emitting end face from the cavity inside of the active layer This is because a window region having a wide forbidden band can be formed.

As described above, by forming the film that triggers the disordering as the SixOyNz film, gallium atoms and the like are removed from the surface of the epitaxially grown wafer immediately below the film.
Vacancy atoms are generated inside the laminated structure that has been sucked up into the z film and epitaxially grown.In addition, due to the difference in thermal expansion coefficient and crystal lattice structure between this laminated structure and the SixOyNz film, the stack Rapid thermal stress occurs in the structure, and the diffusion speed of the vacancy increases. as a result,
Even in the case of annealing aimed at shortening the annealing time and lowering the annealing temperature, a sufficient amount of vacancy atoms diffuses in the direction of the substrate, and the active layer immediately below the SixOyNz film is disordered, and other than the film immediately below the film. The band gap becomes larger than the active layer,
It becomes possible to form a window region without absorption of laser light. Furthermore, since the expansion of the vacancies is promoted by using the stress caused by the film, the annealing time can be reduced and the annealing temperature can be reduced, and unnecessary diffusion of impurities such as Zn can be prevented. Become.

According to a method of manufacturing a semiconductor laser device according to the present invention, a semiconductor laser device having a laminated structure including a lower cladding layer, an active layer, and an upper cladding layer is formed on a substrate using a compound semiconductor containing at least gallium. During manufacturing, a SixOyNz film is formed above the stacked structure near the region to be the laser cavity end face, and after forming a dielectric film on the upper surface of the stacked structure including the SixOyNz film, annealing is performed. The above object is achieved by generating vacancies under the SixOyNz film and diffusing the vacancies until reaching the active layer, thereby disordering the active layer in the vicinity of the laser cavity end face. To achieve.

As described above, since annealing is performed after forming the dielectric film on the laminated structure, it is possible to prevent re-evaporation of impurity atoms from the uppermost layer surface of the laminated structure. It is possible to suppress the diffusion of the impurity atoms generated by the re-evaporation of the impurity atoms. For example,
The top layer of the stacked structure is p-G containing Zn atoms as impurities.
In the case of an aAs layer, re-evaporation of Zn atoms by annealing,
It is possible to suppress the diffusion due to the re-evaporation, and therefore, it is possible to suppress the formation of the remote junction due to the diffusion of Zn atoms into the AlGaAs layer below the stacked structure that forms the n-type cladding layer. It is possible to improve the temperature characteristics of the element.

This dielectric film is preferably a film in which the generation of vacancy atoms in the laminated structure is smaller than that of the SixOyNz film. For example, a Six1Oy1 film, an Alx1Oy1 film, an Alx1Ny1 film
Either a film, a Six1Ny1 film (x1, y1 is 1 or more), or a combination thereof is conceivable.

According to a method of manufacturing a semiconductor laser device according to the present invention, a semiconductor laser device having a laminated structure including a lower cladding layer, an active layer, and an upper cladding layer is formed on a substrate using a compound semiconductor containing at least gallium. In manufacturing, a step of forming a film containing at least silicon among silicon, oxygen, and nitrogen above the stacked structure; and forming an oxygen-containing film in the vicinity of a region to be a laser cavity end face of the film containing at least silicon. After ion implantation of atoms and / or nitrogen atoms to form a SixOyNz film, annealing is performed to generate holes under the SixOyNz film, and the holes are diffused until reaching the active layer, A step of disordering the active layer in the vicinity of a region to be the laser resonator end face, thereby achieving the above object.

As described above, a film containing at least silicon among silicon, oxygen, and nitrogen is formed above the laminated structure, and the film is formed near the laser cavity end face near the region.
Oxygen atoms and / or nitrogen atoms are implanted into SixOyN
By performing annealing after the formation of the z film, the above-described effects can be obtained with a simpler process.

The method of manufacturing a semiconductor laser device according to the present invention achieves the above object by forming the SixOyNz film by implanting nitrogen atoms into the SixOy film.

As described above, by implanting nitrogen atoms into the SixOy film to form the SixOyNz film, the nitrogen atom ions collide with the oxygen atoms in the SixOy film to give energy to the oxygen atoms. These oxygen atoms enter the stacked structure with a certain amount of energy, causing a phenomenon in which vacancy atoms are generated in the semiconductor film forming the stacked structure, so that oxygen atoms are simply implanted without ion implantation of nitrogen atoms. Plasma CV
Compared to the case where a SixOyNz film is formed by using the D method or the sputtering method, it is possible to effectively disorder the active layer by annealing at a lower temperature and for a shorter time.

In the method for manufacturing a semiconductor laser device according to the present invention, the above object is achieved by forming the SixOyNz film by implanting oxygen atoms into the SixNy film.

As described above, oxygen atoms are ion-implanted into the SixNz film to form a SixOyNz film, whereby the oxygen atom ions collide with the nitrogen atoms in the SixNz film and give energy to the nitrogen atoms. The top layer of the laminated structure is GaAs or AlGaA
In the case of s, since nitrogen atoms can penetrate deeper into the stacked structure than oxygen atoms, it is possible to effectively disorder the active layer by annealing at a lower temperature and for a shorter time. Become.

The method of manufacturing a semiconductor laser device according to the present invention achieves the above object by forming the SixOyNz film by implanting nitrogen and oxygen atoms into a Si film.

At this time, after ion implantation of nitrogen atoms,
Oxygen atoms are preferably ion-implanted, and this configuration makes it possible to effectively disorder the active layer by annealing at a lower temperature and for a shorter time.

A method of manufacturing a semiconductor laser device according to the present invention is directed to a multiple quantum well structure in which at least a first conductivity type clad layer, a barrier layer and a well layer are alternately stacked on a first conductivity type semiconductor substrate. Step of sequentially epitaxially growing an active layer sandwiched by a light guide layer and a cladding layer of the second conductivity type, and forming a SixOyNz film on the vicinity of a region to be a light emitting end face of the epitaxially grown layer, followed by annealing. And the step of
Achieve the above objectives.

As described above, when the active layer has a multiple quantum well structure, the effect of not only the diffusion of vacancy atoms but also the diffusion of constituent atoms of the active layer having a multilayer structure of a thin barrier layer and a well layer. Therefore, disordering can be performed more effectively at a lower temperature and in a shorter time.

A method of manufacturing a semiconductor laser device according to the present invention is directed to a multiple quantum well structure in which at least a first conductivity type clad layer, a barrier layer and a well layer are alternately stacked on a first conductivity type semiconductor substrate. Layer, a lower conductive layer of the second conductivity type, an etching stop layer of the second conductivity type, an upper cladding layer of the second conductivity type, and a protective layer of the second conductivity type are sequentially epitaxially grown. Forming a SixOyNz film in the vicinity of a region to be a light emitting end face of the epitaxially grown layer, and annealing; removing the SixOyNz film, and then removing the SixOyNz film; Forming a ridge-shaped stripe structure in the direction of the resonator on the conductive type protective layer, the second conductive type protective layer left by the step, and the second conductive type etch exposed by the step The Gusutoppu layer, by comprising a step of epitaxially growing a first conductivity type current confinement layer, and to achieve the above object.

The method of manufacturing a semiconductor laser device according to the present invention is the same as the method of manufacturing a semiconductor laser device described above, except that
After epitaxially growing the conductivity type current confinement layer, the second
Removing the region of the first conductivity type current confinement layer formed on the conductivity type protection layer, excluding the region near the light emitting end face;
The above object is achieved by being included.

In the method of manufacturing a semiconductor laser device according to the present invention, a multiple quantum well structure in which at least a first conductivity type clad layer, a barrier layer, and a well layer are alternately stacked on a first conductivity type semiconductor substrate is provided. A step of sequentially epitaxially growing an active layer sandwiched between light guide layers, a second conductive type lower clad layer, a second conductive type etching stop layer, a second conductive type upper clad layer, and a second conductive type protective layer. Forming a SixOyNz film in the vicinity of a region to be a light emitting end face of the epitaxially grown layer and annealing the same; and, while leaving the SixOyNz film, the upper cladding layer of the second conductivity type; Forming a ridge-shaped stripe structure in the resonator direction on the protection layer of the mold, the second conductivity type protection layer left by the step, and the second conductivity type etch exposed by the step. The Gusutoppu layer, by comprising a step of epitaxially growing a first conductivity type current confinement layer, and to achieve the above object.

As described above, by leaving the SixOyNz film used for forming the window region, the film can be used as a current non-injection region, and it is not necessary to form a current non-injection region again.

A semiconductor laser device according to the present invention is characterized in that a laminated structure including at least a lower clad layer, an active layer, and an upper clad layer formed on a substrate, and a laser cavity end face above the laminated structure. SixO formed near the region
a semiconductor laser device including a yNz film, wherein the band gap of the active layer is smaller inside the resonator than below the SixOyNz film, thereby achieving the above object.

The semiconductor laser device according to the present invention has a multiple quantum well structure formed on a semiconductor substrate of the first conductivity type, in which at least a first conductivity type cladding layer, a barrier layer and a well layer are alternately stacked. An active layer sandwiching the light guide layer, a lower cladding layer of the second conductivity type, an upper cladding layer of the second conductivity type having a ridge-shaped stripe in the resonator direction, and a first formed to bury the side surfaces of the ridge-shaped stripe. A semiconductor laser device comprising: a conductive type current confinement layer; and a second conductive type protective layer formed on a second conductive type upper cladding layer, which is a light emitting end surface on the second conductive type protective layer. A first conductivity type epitaxial growth layer sandwiched between the (111) plane and the (1-1-1) plane is formed near the region, and the band gap of the active layer near the region serving as the light emitting end face is: Resonator By becoming greater than the band gap of the internal active layer parts, to achieve the above object.

Hereinafter, the operation of the present invention will be described.

According to the semiconductor laser of the present invention and the method of manufacturing the same,
Is the light emission end face of the wafer surface grown epitaxially
Si on the neighboring area_xO_yN_z(X, y, z are 1 or more
Above) After forming the film, the Si_xO_yN_z(X, y, z are 1 or more
Above) film, formed by the epitaxial growth
Since each layer is annealed,_xO_yN_z(X, y, z
Is one or more) Table of epitaxially grown wafers directly under the film
Ga atoms etc. from the surface_xO_yN_z(X, y, z are 1 or more
Above) Wafers absorbed into the film and grown epitaxially
Vacancy atoms are generated inside the c
Lengthened wafer and Si _xO_yN_z(X, y, z are 1 or more)
Due to differences in the coefficient of thermal expansion and crystal lattice structure of the film,_xO_y
N_z(X, y, z are 1 or more)
Rapid thermal stress occurs on the elongated wafer,
The diffusion rate of pore atoms increases. As a result, the annealing time
Annealing that shortens the annealing time and lowers the annealing temperature
However, a sufficient amount of vacancy atoms diffuse toward the substrate,
Si_xO_yN_z(X, y, z are 1 or more) of the active layer immediately below the film
Window with large band gap and no absorption of laser light
Can be an area. Furthermore, shortening of annealing time
And the annealing temperature can be lowered, so that Zn
Diffusion of impurities such as atoms can be suppressed.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail. Embodiment 1 FIG. 1 is a sectional view showing the structure of a semiconductor laser device of Embodiment 1. 1A is a perspective view including a light emitting end face, FIG. 1B is a cross-sectional view of a waveguide taken along the line Ia-Ia ′ in FIG. 1A, and FIG. It is sectional drawing in the layer thickness direction in Ib 'line. 1 is n-type GaAs
The substrate, 2 is an n-type AlGaAs first cladding layer, 3 is an active layer (MQW active layer) in which a multiple quantum well structure in which barrier layers and well layers are alternately stacked is sandwiched between optical guide layers, and 4 is p-type AlGaAs. The second clad layer, 5 is a p-type etching stop layer, 6 is a p-type AlGaAs third clad layer composed of a ridge stripe in the resonator direction, and 7 is p-type GaAs.
A protective layer 8 is a p-type AlGaAs composed of a ridge stripe.
An n-type AlGaAs current blocking layer formed so as to bury the side surface of the s third cladding layer, 9 is a p-type GaAs planarization layer, 10 is a p-type GaAs contact layer, 11 is a p-side electrode, and 12 is an n-side electrode. is there. Also, 13 Si _x O _y N _z
(X, y, z are 1 or more) a region (window region) where the bandgap energy of the MQW active layer immediately below the film is larger than the bandgap energy of the MQW active layer 3 inside the resonator;
Reference numeral 14 denotes an n-type AlG formed on the p-type GaAs protective layer 7.
aAs current blocking layer 8a and p-type GaAs planarization layer 9a
15 is a p-type AlGaAs third region.
This is a stripe-shaped ridge composed of a cladding layer 6 and a p-type GaAs protective layer 7.

Next, the manufacturing method will be described with reference to FIG. A multiple quantum well structure in which an n-type AlGaAs first cladding layer 2, a barrier layer, and a well layer are alternately stacked on an n-type GaAs substrate 1 sequentially by metal organic chemical vapor deposition (MOCVD) is sandwiched by optical guide layers. An active layer (MQW active layer) 3, a p-type AlGaAs second cladding layer 4, a p-type etching stop layer 5, a p-type AlGaAs third cladding layer 6, and a p-type GaAs protective layer 7 are epitaxially grown (FIG. 2 (a)). )).

Thereafter, the p-type Ga in the vicinity of the light emitting end face portion is formed.
On the surface of As protective layer 7, by a plasma CVD method and the photolithography method, the width 40μm stripe in a direction perpendicular to the ridge _{stripe, Si x O y N z (} x,
(y and z are 1 or more) The film 16 is formed. Si _x O _y N _z by plasma CVD (x, y, z is 1 or more) film formation conditions, as the raw material gas, SiH _4, N ₂ O, and N ₂ used, RF
The film was formed at a power of 100 W, a substrate temperature of 280 ° C. and a film thickness of 5000 °. The stripe pitch was 800 μm, which is the same as the resonator length (FIG. 2B).

The Si _x O _y N obtained by the above film forming method
_z (x, y, z is 1 or more) the film 16 secondary ion mass spectrometry (SIMS) results of measurement in the apparatus, the nitrogen atom is a high density detection, also using an ellipsometer, the Si _x O _y
As a result of measuring the refractive index of the N _z (x, y, z is 1 or more) film 16, the refractive index of the SiO ₂ film (1.4) and the refractive index of the SiN film (1.8 to 2.5) are intermediate. The value was 1.6. Than the _{result, Si x O y N z (} x, y, z is 1 or more) it is clear that the film is formed.

Next, rapid thermal annealing (RT
A) Annealing by the method _xO_yN_z(X,
y, z are 1 or more) MQW active layer immediately below the film 16 (window region)
13 band gap energy to the MQW inside the resonator.
From the band gap energy of the active layer (active region) 3
Also make it bigger. The annealing condition at this time is a temperature of 950.
C., the temperature was raised at a rate of 100 ° C./second, and the holding time was 20 seconds.

Thereafter, the p-type Ga in the vicinity of the light-emitting end face is obtained.
Formed on the surface of the As protecting layer _{7 Si x O y N z (} x,
y, z are 1 or more) The film 16 is removed, a striped resist mask 17 is formed on the p-type GaAs protective layer 7 using a known photolithography technique, and p-type etching is performed using a known etching technique. The p-type GaAs protective layer 7 and the p-type AlGaAs
The cladding layer 6 is formed as a stripe-shaped ridge 15 having a width of about 3 μm.
(FIG. 2C).

Next, the striped resist mask 17 formed on the p-type GaAs protective layer 7 is removed, and the p-type GaAs protective layer 7 and the p-type AlGaAs third cladding layer 6 are removed by the second MOCVD method. The side surface of the ridge 15 is formed with the n-type AlGaAs current block layer 8 and the p-type GaAs.
It is buried with the flattening layer 9 (FIG. 2D).

Using a part of the wafer, the cross section of the wafer was measured with a scanning electron microscope (SEM). As a result, the n-type Al formed on the p-type GaAs protective layer 7 of the ridge 15 was measured.
GaAs current blocking layer 8 and p-type GaAs planarizing layer 9
Has a shape sandwiched between the (111) plane and the (1-1-1) plane, and the ridge-like stripe shape in the wafer plane is similarly arranged. The width (stripe width) of the cladding layer 6 on the substrate side is 2.9 to
The side surfaces of the ridge 15 were buried with the n-type AlGaAs current blocking layer 8 and the p-type GaAs planarization layer 9 very flatly, having a very small variation of 3.0 μm.

The n-type AlGaAs current blocking layer 8
If the crystallinity of the wafer is poor, the function as a current confinement part may be reduced and a leak current may occur. However, as a result of measuring the current confinement part of the wafer by the X-ray diffraction method, n-type Al
The half width of the GaAs current blocking layer 8 was 25 seconds, and a film having good crystallinity was obtained, which was a result without any problem.

Thereafter, the p-type GaAs planarization layer 9 formed on the side surface of the ridge 15 using a known photolithography technique, and the p-type GaAs formed on the ridge 15
A resist mask 18 is provided near the light emitting end face of the planarizing layer 9.
Is formed, and the n-type AlGaAs current blocking layer 8 and the p-type GaAs planarization layer 9 at the opening of the resist mask 18 are selectively removed using a known etching technique (FIG. 2).
(E)).

The n-type AlGaAs formed on the ridge 15
The step of removing the s current block layer 8 and the p-type GaAs planarization layer 9 also serves as a step of forming the current non-injection region 14, so that the number of steps can be reduced. Since the current non-injection region 14 is located immediately above the window region 13, current injection into the window region is prevented, and carrier loss due to the presence of a vacancy defect in the window region can be suppressed. Reduced.

In the step of selectively removing the n-type AlGaAs current blocking layer 8 and the p-type GaAs planarization layer 9, the n-type AlGaAs current blocking layer formed on the p-type GaAs protection layer 7 of the ridge 15 is removed. Layer 8 and p-type Ga
When the As flattening layer 9 is shifted from the shape sandwiched between the (111) plane and the (1-1-1) plane, it cannot be selectively removed, and the p-type of the ridge 15 in the cavity inside region cannot be removed. GaAs
Since the n-type AlGaAs current blocking layer 8 remains on the protective layer 7, the ridge has a reduced function as a current path. However, in the present embodiment, as described above, (11
Since the shape is sandwiched between the (1) plane and the (1-1-1) plane, the ridge 15 in the cavity internal region is formed over the entire surface of the wafer.
Since the n-type AlGaAs current blocking layer 8 does not remain on the p-type GaAs protective layer 7, the electric characteristics such as the driving current in the wafer surface do not vary.

Next, the resist mask 18 formed on the p-type GaAs planarization layer 9 is removed, and the third MOCVD
The p-type GaAs contact layer 10 is formed by the method
(F)). Further, a p-electrode 11 is formed on the upper surface, and an n-electrode 12 is formed on the lower surface.

Next, a scribe line is placed substantially at the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

Using a part of the wafer after annealing by the RTA method, a photoluminescence (PL) method is used.
_{Si x O y N z (x} , y, z is 1 or more) MQ directly below membrane 16
The respective wavelengths of the W active layer (window region) 13 and the MQW active layer (active region) 3 inside the resonator were measured. For comparison, the _{Si x O y N z (x} , y, z is 1 or more)
The film 16 is a prior art Si _x O _{y (x, y} is 1 or more) at the same time the wafer was changed to the film at PL method, Si _x O
_y (x and y are 1 or more) MQW active layer directly under the film (window area)
And the respective wavelengths of the MQW active layer (active region) inside the resonator.

[0056] As a _{result, Si x O y N z (} x, y, z is 1
Above) The emission spectrum from the MQW active layer 13 immediately below the film 16 is shifted by 30 nm to a shorter wavelength side than the emission spectrum from the MQW active layer 3 inside the resonator.
i _x O _{y (x, y} is 1 or more) emission spectrum from the MQW active layer immediately below membranes were wavelength shift to 10nm shorter wavelength side than the emission spectrum from the resonator inside the MQW active layer. Therefore, if the annealing conditions by RTA method is the _{same, Si x O y N z (} x, y, z is 1 or more) is used, it is obvious that increasing the amount of wavelength shift of the window region.

[0057] Further, the annealing time by the RTA method in FIG. 10, Si _x O _y N _z of the present invention (x, y, z is 1 or more) when using a membrane, and a prior art Si _x O _y (X, y
Indicates the relationship between the wavelength of the active region and the wavelength shift amount of the window region when a film is used. At this time, the annealing temperature was 950 ° C., the rate of temperature rise was 100 ° C./sec, and the wavelengths in the window region were all shifted to the shorter wavelength side with respect to the wavelengths in the active region. In FIG. 10, the vertical axis represents the wavelength shift amount (nm) of the window region with respect to the wavelength of the active region, and the horizontal axis represents the annealing time (second).
, And the solid lines show the present invention _{Si x O y N z (x} , y,
When z is using one or more) _{film, Si x O y (x,} y broken line shows the prior art in the figure shows one or more) wavelength shift amount of the window region when using a membrane.

[0058] As can be seen from FIG. 10, in order to 30nm shifting a wavelength of the window region to the shorter wavelength side with respect to the wavelength of the active region is a prior art Si _x O _{y (x, y} is 1 or more)
When a film is used, an annealing time of 60 seconds is required,
Si _x O _y N _z of the present invention if (x, y, z are the 1 or higher) was used, the annealing time may be a 20-second, Si _x O _y of the present invention
It is clear that the annealing time can be shortened by using N _z (x, y, z is 1 or more).

[0059] In the manufacturing method of the present invention, by performing the annealing by RTA _{method, Si x O y N z (} x,
y, z is 1 or more) Ga from the surface of the p-type GaAs protective layer 7 directly under film 16, As atoms are _{Si x O y N z (x} , y, z is 1 or more) sucked up in the film 16, GaAs crystals inside voids atom is generated, also, the wafer and Si have been grown epitaxially _x O _y N _z by the difference of (x, y, z is 1 or more) thermal expansion coefficient and the crystal lattice structure of the film 16, Si _x O _y N
_z (x, y, z is 1 or more) Abrupt thermal stress occurs in the epitaxially grown wafer immediately below the film 16. The _{stress, Si x O y (x,} y is 1 or more) greater than with film, the greater the stress, an attempt to dissipate the stress on the rapidly epitaxially grown wafer, the vacancy atoms Accelerates the diffusion speed and diffuses in the direction of the n-type GaAs substrate 1. As a result, even in the case of RTA for a very short time, a sufficient amount of vacancy atoms diffuse in the direction of the n-type GaAs substrate 1 and M
Since the QW active layer can be disordered, Si _x O _y
The band gap energy of the MQW active layer 13 immediately below the N _z (x, y, z is 1 or more) film 16 increases, and the window has a wider bandgap than the MQW active layer (active region) 3 inside the resonator. An area is formed.

The characteristics of the semiconductor laser device obtained by the above-described manufacturing method of the present invention were measured.

For comparison, the production of the present invention
In the method, the Si_xO_yN_z(X, y, z are 1 or more)
16 to Si_xO_y(X and y are 1 or more) Change to membrane, and
Si _xO_y(X and y are 1 or more) from the MQW active layer immediately below the film
Emission spectrum from the MQW active layer inside the resonator
The wavelength will be shifted by 30nm shorter than the optical spectrum.
As described above, the annealing conditions were set at a temperature of 950 ° C. and a temperature increase rate of 100 ° C.
/ S, half of the prior art obtained by changing the holding time to 60 seconds.
The characteristics of the semiconductor laser element were also measured at the same time.

As a result, the oscillation wavelength (λ) at a CW of 120 mW was 785 nm for both the semiconductor laser device of the present invention and the prior art, and the CW of 120 m for the semiconductor laser device of the present invention.
The drive current (Iop) at W is 170 mA, and the drive current (Io) at CW of 120 mW of the conventional semiconductor laser device.
p) is 210 mA, CW1 of the semiconductor laser device of the present invention.
The driving voltage (Vop) at 20 mW is 2.1 V, and the driving voltage (Vop) at 120 mW of CW of the conventional semiconductor laser device is
op) is 2.4 V, and it is clear that in the method for manufacturing a semiconductor laser device of the present invention, a lower drive current and a lower drive voltage are realized. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by shortening the annealing time by the RTA method.

The results of the maximum light output test show that the semiconductor laser devices of the present invention and the prior art are COD-free even at a light output of 300 mW or more.
When a reliability test of 120 mW was performed, the average life of the semiconductor laser device of the prior art was 1000 hours, whereas the average life of the semiconductor laser device of the present invention was approximately 2000 hours, which is about twice as long.

[0064] In this _{example, Si x O y N z (} x, y, z
1 or more), but the film 16 was formed by a plasma CVD method, even by using a sputtering _{method, Si x O y N z (} x, y, z
At the time of film formation, vacancy atoms are generated due to plasma damage on the surface of the epitaxially grown wafer, and the active layer near the light emitting end face is effectively made more effective than the active layer (active region) inside the resonator. Since a window region having a wide forbidden band width can be formed at the same time, the same effect as described above can be obtained.

In this embodiment, an AlGaAs semiconductor laser has been described, but the same effect can be obtained with an AlGaInP semiconductor laser. Second Embodiment A manufacturing method according to a second embodiment will be described with reference to FIG.
On the n-type GaAs substrate 301, n is sequentially formed by MOCVD.
-Type AlGaAs first cladding layer 302, MQW active layer 3
03, a p-type AlGaAs second cladding layer 304, a p-type etching stop layer 305, a p-type AlGaAs third cladding layer 306, and a p-type GaAs protective layer 307 are epitaxially grown.

Thereafter, the p-type Ga in the vicinity of the light-emitting end face is obtained.
On the surface of As protective layer 307 by plasma CVD method and photolithography, the width 40μm stripe in a direction perpendicular to the ridge _{stripe, Si x O y (x,} y
1 or more) film 319 is _{formed, Si x O y (x,} y in a region where one or more) film 319 is not formed, the protective film 322
To form a resist mask. Si _x O _y by plasma CVD (x, y is 1 or more) film formation conditions, as the raw material gas, SiH _4, N ₂ O, and N ₂ used, RF power 15
W was formed at a substrate temperature of 280 ° C. and a film thickness of 5000 °.
The protective layer 322 _{is, Si x O y (x,} y is 1 or more) film 3
P-type GaAs protective layer 30 in a region where 19 is not formed
7, which nitrogen atom is formed in order not ion-implanted, the film thickness is Si _x O _y protective layer 322 (x, y is 1 or more) is preferable to thicker than the thickness of the film 319. Note that the stripe pitch is 800, which is the same as the resonator length.
μm (FIG. 3A).

Next, a p-type GaAs near the light emitting end face is used.
Si formed on the surface of the s protective layer 307 _x O _{y (x, y} is 1 or more) to the membrane 319, ion implantation of nitrogen atoms. Thereby, the surface Si _x O _y N _z of the p-type GaAs protective layer 307 serving as a light emission end surface portion near (x, y, z is 1 or more) film 316 is formed. The ion implantation conditions include an ion acceleration energy of 150 keV and a dose of 1E14c.
m ^-2 . After the ion implantation step, only the protective film 322 is removed (FIG. 3B), and thereafter, annealing by the RTA method is performed. The annealing conditions at this time are as follows: temperature 750 ° C.
The test was carried out at a heating rate of 100 ° C./sec and a holding time of 60 sec.

[0068] Then, the light-emitting end becomes face near the nitrogen atom formed on the surface of the p-type GaAs protective layer 307 is implanted Si _x O _{y (x, y} is 1 or more) film 316 is removed, known P-type Ga using photolithography technology
Striped resist mask 3 on As protective layer 307
17 is formed, and p-type GaAs is reached using a known etching technique so as to reach the p-type etching stop layer 305.
s protective layer 307 and p-type AlGaAs third cladding layer 30
6 is processed into a stripe-shaped ridge 315 having a width of about 3 μm (FIG. 3C).

Next, the striped resist mask 317 formed on the p-type GaAs protective layer 307 is removed.
By the second MOCVD method, the p-type GaAs protective layer 3 is formed.
07 and the p-type AlGaAs third cladding layer 306 are embedded on the side surfaces of the ridge 315 with an n-type AlGaAs current block layer 308 and a p-type GaAs planarization layer 309 (FIG. 3).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 315 by using a known photolithography technique.
Planarization layer 309 and p formed on ridge 315
Mask 318 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 309, and the n-type AlGaAs current block layer 308 and the p-type GaAs planarization layer 309 at the opening of the resist mask 318 are formed by a known etching technique. It is selectively removed to form a current non-injection region 314 (FIG. 3E).

Next, the resist mask 318 formed on the p-type GaAs planarization layer 309 is removed, and the third MO
A p-type GaAs contact layer 310 is formed by a CVD method (FIG. 3F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed almost at the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

[0073] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 31 immediately below the film 316
3 and inside the resonator of the MQW active layer (active region) 303 of the result of the respective wavelengths were measured, despite the low temperature of _{750 ℃, Si x O y N} z (x, y, z is 1 or more) film The emission spectrum from the MQW active layer 313 immediately below 316 was shifted to a shorter wavelength side by 40 nm than the emission spectrum from the MQW active layer 303 inside the resonator.

[0074] Further, the annealing temperature by RTA method in FIG. 11, Si _x O _y N _z of the present invention (x, y, z is 1 or more) when using a membrane, and a prior art Si _x O _y (X, y
Indicates the relationship between the wavelength of the active region and the wavelength shift amount of the window region when a film is used. At this time, the annealing time was 60 seconds, the heating rate was 100 ° C./second, and the wavelengths in the window region were all shifted to the shorter wavelength side with respect to the wavelengths in the active region. Vertical axis indicates the wavelength shift amount of the window region to the wavelength of the active region in FIG. 11 (nm), the horizontal axis represents the annealing temperature _{(℃), Si x O y} N z (x solid lines present invention in FIG., Y , Z
1 or more) when using the _{film, Si x O y (x,} y broken line shows the prior art in the figure shows one or more) wavelength shift amount of the window region when using a membrane.

[0075] As can be seen from Figure 11, in order to 30nm shifting a wavelength of the window region to the shorter wavelength side with respect to the wavelength of the active region is a prior art Si _x O _{y (x, y} is 1 or more)
When a film is used, the annealing temperature must be 950 ° C., but when _Six O _y N _z (x, y, z is 1 or more) of the present invention is used, the annealing temperature may be as low as 730 ° C. , Si _x O _y N _z of the present invention (x, y, z is 1 or more)
It is clear that the annealing temperature can be lowered by using.

[0076] In the above manufacturing method, the surface of the p-type GaAs protective layer 307 serving as a light emission end surface portion near Si _x O _{y (x,}
y is 1 or more) to form a film 319, by ion implantation of nitrogen _{atom, Si x O y N z (} x, y, z is 1 or more) film 316 is formed. At this time, the nitrogen atom _{ions, Si x O y (x,} y is 1 or more) collide with oxygen atoms in the film 319, providing energy to the oxygen atom. The colliding oxygen atoms enter the p-type GaAs protective layer 307 with a certain amount of energy, and the p-type GaAs protective layer 307
Vacancy atoms are generated inside. In this state, annealing by the RTA method is performed. Therefore, even at a low temperature of 750 ° C., the amount of vacancies generated inside the GaAs crystal increases as compared with the manufacturing method of the first embodiment, and a rapid thermal stress occurs. This increases the diffusion rate of the vacancy atoms. as a result,
Even when annealing by the RTA method at a very low temperature, a sufficient amount of vacancy atoms diffuse in the direction of the n-type GaAs substrate 1 and the MQW active layer can be disordered.
_{Si x O y N z (x} , y, z is 1 or more) M directly below membrane 316
The band gap energy of the QW active layer 313 increases, and a window region having a wider forbidden band than the MQW active layer (active region) 303 inside the resonator is formed.

The characteristics of the semiconductor laser device obtained by the manufacturing method of the present embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW is 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, and it is clear that a lower drive current and a lower drive voltage are realized as compared with the semiconductor laser device obtained by the manufacturing method of the first embodiment. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method.

The result of the maximum light output test was 300 mW.
COD-free even at the above light output, 70 ° C1
When a reliability test of 20 mW was performed, the average life was improved to about 2500 hours.

This is because the difference in band gap energy between the active region 303 and the window region 313 is further increased.
This is because the absorption of the wavelength of the laser light generated in the active region 303 is reduced as compared with the semiconductor laser device obtained by the manufacturing method of the first embodiment.

In the present embodiment, the Si
_The conditions for forming the _xOy (x, y is 1 or more) film 319 were that SiH ₄ , N ₂ O, and N ₂ were used as source gases, but SiH ₄ , O ₂
The same effect as described above can be obtained by using.

[0082] In this _{example, Si x O y (x,} y is 1 or more), but the film 319 is formed using a plasma CVD method,
The same effect as described above can be obtained by using the sputtering method.

In this embodiment, an AlGaAs semiconductor laser has been described. However, similar effects can be obtained with an AlGaInP semiconductor laser. Third Embodiment A manufacturing method according to a third embodiment will be described with reference to FIG.
On the n-type GaAs substrate 401, n is sequentially formed by MOCVD.
Type AlGaAs first cladding layer 402, MQW active layer 4
03, the p-type AlGaAs second cladding layer 404, the p-type etching stop layer 405, the p-type AlGaAs third cladding layer 406, and the p-type GaAs protection layer 407 are epitaxially grown.

Thereafter, the p-type Ga in the vicinity of the light emitting end face portion is formed.
On the surface of As protective layer 407 by plasma CVD method and photolithography, the width 40μm stripe in a direction perpendicular to the ridge _{stripe, Si x N z (x,} z
1 or more) film 420 is _{formed, Si x N z (x,} z in a region where one or more) film 420 is not formed, the protective film 422
To form a resist mask. The conditions for forming a Si _x N _z (x, z is 1 or more) film by plasma CVD are as follows: SiH ₄ , NH ₃ , N ₂ are used as source gases, and RF power is 150.
W was formed at a substrate temperature of 280 ° C. and a film thickness of 5000 °.
The protective layer 422 _{is, Si x N z (x,} z is 1 or more) film 4
P-type GaAs protective layer 40 in a region where 20 is not formed
7, which is an oxygen atom is formed in order not ion-implanted, the film thickness is Si _x N _Z of the protective film 422 (x, z is 1 or more) is preferable to thicker than the thickness of the film 420. Note that the stripe pitch is 800, which is the same as the resonator length.
μm (FIG. 4A).

Next, a p-type GaAs near the light emitting end face is used.
Si _x N _z formed on the surface of the s protective layer 407 (x, z is 1 or more) to the membrane 420, ion implantation of oxygen atoms. Thereby, the surface Si _x O _y N _z of the p-type GaAs protective layer 407 serving as a light emission end surface portion near (x, y, z is 1 or more) film 416 is formed. As the ion implantation conditions, the ion acceleration energy is 150 keV and the dose is 1E15c.
m ^-2 . After the ion implantation step, only the protective film 422 is removed (FIG. 4B), and then annealing is performed by the RTA method. The annealing conditions at this time are as follows: temperature 750 ° C.
The test was carried out at a heating rate of 100 ° C./sec and a holding time of 60 sec.

After that, the Si _x N _z (x, z is 1 or more) film 416 implanted with oxygen atoms formed on the surface of the p-type GaAs protective layer 407 near the light emitting end face is removed. P-type Ga using photolithography technology
Striped resist mask 4 on As protective layer 407
17 is formed and p-type GaAs is formed using a known etching technique so as to reach the p-type etching stop layer 405.
s protective layer 407 and p-type AlGaAs third cladding layer 40
6 is processed into a stripe-shaped ridge 415 having a width of about 3 μm (FIG. 4C).

Next, the striped resist mask 417 formed on the p-type GaAs protective layer 407 is removed.
By the second MOCVD method, the p-type GaAs protective layer 4 is formed.
7 and the p-type AlGaAs third cladding layer 406 are buried with side surfaces of a ridge 415 with an n-type AlGaAs current blocking layer 408 and a p-type GaAs planarization layer 409 (FIG. 4).
(D)).

Then, the p-type GaAs formed on the side surface of the ridge 415 by using a known photolithography technique.
Planarization layer 409 and p formed on ridge 415
Mask 418 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 409, and the n-type AlGaAs current block layer 408 and the p-type GaAs planarization layer 409 at the opening of the resist mask 418 are formed by using a known etching technique. It is selectively removed to form a current non-injection region 414 (FIG. 4E).

Next, the resist mask 418 formed on the p-type GaAs planarization layer 409 is removed, and the third MO
A p-type GaAs contact layer 410 is formed by a CVD method (FIG. 4F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed substantially in the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

[0091] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 41 immediately below film 416
3 and inside the resonator of the MQW active layer (active region) results of each wavelength was measured for _{403, Si x O y N z} (x, y,
(z is 1 or more) The emission spectrum from the MQW active layer 413 immediately below the film 416 was shifted by 50 nm to a shorter wavelength side than the emission spectrum from the MQW active layer 403 inside the resonator.

[0092] In the above manufacturing method, the surface of the p-type GaAs protective layer 407 serving as a light emission end surface portion near Si _x N _{z (x,}
z is 1 or more) to form a film 420, by ion implantation of oxygen _{atoms, Si x O y N z (} x, y, z is 1 or more) film 416 is formed. At this time, an oxygen atom _{ions, Si x N z (x,} z is 1 or more) collide with the nitrogen atom in the film 420, energizes nitrogen atom, p-type GaAs the nitrogen atom with a certain degree of energy Protective layer 4
Go into 07. Nitrogen atom is more GaAs than oxygen atom
Since it can penetrate deep into the s crystal, vacancy atoms are generated deeper from the surface of the p-type GaAs protective layer 407 as compared with the manufacturing methods of the first and second embodiments. Therefore, by performing the annealing by the RTA method, the region where the vacancy atoms generated inside the GaAs crystal are expanded, and a sufficient amount of the vacancy atoms quickly reach the MQW active layer. it is possible to _{disordering, Si x O y N z (} x, y, z
The band gap energy of the MQW active layer 413 immediately below the film 416 increases, and the MQW
A window region having a wider bandgap is formed effectively than the active layer (active region) 403.

The characteristics of the semiconductor laser device obtained by the manufacturing method of the present embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW was 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, and it is clear that a lower drive current and a lower drive voltage are realized as compared with the semiconductor laser device obtained by the manufacturing method of the first embodiment. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method.

The result of the maximum light output test was 300 mW.
COD-free even at the above light output, 70 ° C1
When a reliability test of 20 mW was performed, the average life was improved to about 3000 hours.

This is because the difference in band gap energy between the active region 403 and the window region 413 is further increased.
This is because the absorption of the wavelength of the laser light generated in the active region 403 is reduced as compared with the semiconductor laser devices obtained by the manufacturing methods of the first and second embodiments.

[0097] In this _{example, Si x N z (x,} z is 1 or more), but the film 420 is formed using a plasma CVD method,
The same effect as described above can be obtained by using the sputtering method.

In this embodiment, an AlGaAs semiconductor laser is described, but the same effect can be obtained with an AlGaInP semiconductor laser. Embodiment 4 A manufacturing method of Embodiment 4 will be described with reference to FIG.
On the n-type GaAs substrate 501, n is sequentially formed by MOCVD.
Type AlGaAs first cladding layer 502, MQW active layer 5
03, a p-type AlGaAs second cladding layer 504, a p-type etching stop layer 505, a p-type AlGaAs third cladding layer 506, and a p-type GaAs protective layer 507 are epitaxially grown.

Thereafter, the p-type Ga in the vicinity of the light emitting end face is formed.
An Si film 521 is formed on the surface of the As protective layer 507 by electron beam evaporation and photolithography in a stripe shape having a width of 40 μm in a direction orthogonal to the ridge stripe, and protection is performed in a region where the Si film 521 is not formed. A resist mask is formed as the film 522. The protective film 5
Reference numeral 22 denotes a p-type G in a region where the Si film 521 is not formed.
The aAs protection layer 507 is formed so that nitrogen atoms and oxygen atoms are not ion-implanted.
2 is preferably formed thicker than the Si film 521. Note that the stripe pitch is the same as the resonator length, 8
The thickness was set to 00 μm (FIG. 5A).

Next, the p-type GaAs near the light emitting end face is used.
Nitrogen atoms are ion-implanted into the Si film 521 formed on the surface of the s protective layer 507, and then oxygen atoms are ion-implanted. Thus, Si on the surface of the p-type GaAs protective layer 507 serving as a light emission end surface portion near _{x O y N z (x,} y,
z is 1 or more) A film 516 is formed. The condition for ion implantation of oxygen atoms is that the ion acceleration energy is 150 ke.
V, the dose is 1E15 cm ^-2 , and the ion implantation energy of the nitrogen atom is 150 k.
eV and the dose were 1E14 cm ^-2 .

After the ion implantation step, only the protective film 522 is removed (FIG. 5B), and thereafter, annealing by the RTA method is performed. The annealing conditions at this time were a temperature of 750 ° C., a temperature rising rate of 100 ° C./sec, and a holding time of 60 seconds.

[0102] Then, the light-emitting end becomes face near the nitrogen atom formed on the surface of the p-type GaAs protective layer 507 is implanted Si _x O _{y (x, y} is 1 or more) film 516 is removed, known P-type Ga using photolithography technology
Striped resist mask 5 on As protective layer 507
17 is formed, and p-type GaAs is formed using a known etching technique so as to reach the p-type etching stop layer 505.
s protective layer 507 and p-type AlGaAs third cladding layer 50
6 is processed into a stripe-shaped ridge 515 having a width of about 3 μm (FIG. 5C).

Next, the striped resist mask 517 formed on the p-type GaAs protective layer 507 is removed.
By the second MOCVD method, the p-type GaAs protective layer 5 is formed.
07 and a p-type AlGaAs third cladding layer 506, the side surface of the ridge 515 is embedded with an n-type AlGaAs current blocking layer 508 and a p-type GaAs planarization layer 509 (FIG. 5).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 515 by using a known photolithography technique.
The planarization layer 509 and the p formed on the ridge 515
A resist mask 518 is formed in the vicinity of the light emitting end face of the type GaAs flattening layer 509, and the n-type AlGaAs current block layer 508 and the p-type GaAs flattening layer 509 at the opening of the resist mask 518 are formed by using a known etching technique. It is selectively removed to form a current non-injection region 514 (FIG. 5E).

Next, the resist mask 518 formed on the p-type GaAs planarization layer 509 is removed, and the third MO
A p-type GaAs contact layer 510 is formed by a CVD method (FIG. 5F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed substantially at the center of the window area having a width of 40 μm, and the resonator is divided into bars in the length of the resonator to form a resonator. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

[0107] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 51 immediately below film 516
3 and inside the resonator of the MQW active layer (active region) results of each wavelength was measured for _{503, Si x O y N z} (x, y,
(z is 1 or more) The emission spectrum from the MQW active layer 513 immediately below the film 516 was shifted by 60 nm to a shorter wavelength side than the emission spectrum from the MQW active layer 503 inside the resonator.

In the above-described manufacturing method, the Si film 521 is formed on the surface of the p-type GaAs protective layer 507 near the light emitting end face, and nitrogen atoms are ion-implanted. Collides with Si atoms in the
Gives energy to the i atom. Si atom ions having a certain amount of energy are more G
Although it does not enter the aAs crystal much, the vicinity of the interface between the Si film 521 and the p-type GaAs protective layer 507 is mixed and crystallized. Subsequently by ion implantation of oxygen atoms, Si _x O _y N
_{A z} (x, y, z is 1 or more) film 516 is formed. At this time, oxygen atom ions collide with nitrogen atoms in the Si film 521 to give energy to the nitrogen atoms. Si film 52
Due to the mixed crystal in the vicinity of the interface of the 1 / p-type GaAs protective layer 507, it becomes difficult for the Si film 521 / p-type GaAs protective layer 507 to be trapped at the interface level. A large amount of vacancy atoms are generated deep from the surface of the layer 507. Therefore, by performing annealing by the RTA method, the region where vacancy atoms are generated inside the GaAs crystal and the vacancy amount are further increased, and a sufficient amount of vacancy atoms quickly reach the MQW active layer. , MQW active layer can be disordered,
_{i x O y N z (x} , y, z is 1 or more) MQ directly below membrane 516
The band gap energy of the W active layer 513 is increased, and a window region having a wider bandgap is formed effectively than the MQW active layer (active region) 503 inside the resonator.

In the above manufacturing method, the p-type Ga
After forming a Si film on the entire surface of the As protective layer 507,
By performing ion implantation of oxygen atoms and nitrogen atoms into the Si film on the neighboring region which becomes the light emitting end face, the Si _x O _y N
_z (x, y, z is 1 or more) film is formed,
By implanting nitrogen atoms into the film and then implanting oxygen atoms, the p-type GaAs protective layer 50 is effectively removed.
The region where the vacancy atoms exist inside 7 can be enlarged, and a window region having a wider bandgap than the active region 503 can be formed effectively.

The characteristics of the semiconductor laser device obtained by the manufacturing method of the present embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW was 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, and it is clear that a lower drive current and a lower drive voltage are realized as compared with the semiconductor laser device obtained by the manufacturing method of the first embodiment. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method.

The result of the maximum light output test was 300 mW.
COD-free even at the above light output, 70 ° C1
When a reliability test of 20 mW was performed, the average life was improved to about 4000 hours.

This is because the difference in band gap energy between the active region 503 and the window region 513 is further increased.
This is because the absorption of the wavelength of the laser light generated in the active region 503 is reduced as compared with the semiconductor laser devices obtained by the manufacturing methods of Examples 1 to 3.

In this embodiment, an AlGaAs semiconductor laser has been described. However, similar effects can be obtained with an AlGaInP semiconductor laser. Fifth Embodiment A manufacturing method according to a fifth embodiment will be described with reference to FIG.
On the n-type GaAs substrate 601, n is sequentially formed by MOCVD.
AlGaAs first cladding layer 602, MQW active layer 6
03, a p-type AlGaAs second cladding layer 604, a p-type etching stop layer 605, a p-type AlGaAs third cladding layer 606, and a p-type GaAs protection layer 607 are epitaxially grown.

Thereafter, the p-type Ga in the vicinity of the light-emitting end face is obtained.
On the surface of As protective layer 607 by plasma CVD method and photolithography, the width 40μm stripe in a direction perpendicular to the ridge stripe, Si _x O _y N
_{A z} (x, y, z is 1 or more) film 616 is formed. Plasma by _{CVD Si x O y N z (} x, y, z is 1 or more) film formation conditions, 500 as a source gas, SiH _4, N ₂ O, with N _2, RF power 100W, at a substrate temperature of 280 ° C.
It was formed with a thickness of 0 °. The pitch of the stripe was 800 μm, which is the same as the length of the resonator (FIG. 6A).

Next, the p-type GaAs near the light emitting end face is used.
formed on the surface of the s protective layer _{607 Si x O y N z (} x,
y, z 1 or more) film 616 _{and,, Si x O y N z} (x,
y and z are 1 or more) p-type Ga in which the film 616 is not formed
The As protecting layer 607 surface by a plasma CVD method, a dielectric film Si _x O _{y (x, y} is 1 or more) to form a film 623. Si _x O _y by plasma CVD (x, y is 1 or more) film formation conditions, as the raw material gas, SiH _4, N ₂ O,
Using N ₂ , RF power 15W, substrate temperature 280 ° C, 50
The film was formed with a thickness of 0 ° (FIG. 6B).

Thereafter, annealing by the RTA method is performed.
The annealing conditions at this time are a temperature of 950 ° C.,
The test was performed at 0 ° C./sec and a holding time of 20 seconds.

[0118] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 61 immediately below the film 616
3 and the MQW active layer (active region) 603 inside the resonator, the emission spectrum from the window region 613 was shifted by 30 nm to the shorter wavelength side than the emission spectrum from the active region 603. cage, Si _x O _y
N _z (x, y, _z is 1 or more) film 616 surface, and, p-type GaAs protective layer 607 surface, Si _x O _y is a dielectric film
(X and y are 1 or more) The same as in the case where annealing was performed using the RTA method without forming the film 623.

[0119] Thereafter, the Si _x O _{y (x, y} is 1 or more)
Film 623 and the _{Si x O y N z (x} , y, z is 1 or more) film 6
16 is removed, a stripe-shaped resist mask 617 is formed on the p-type GaAs protective layer 607 by using a known photolithography technique, and the p-type etching stop layer 605 is reached by using a known etching technique. A p-type GaAs protective layer 607 and a p-type AlGaAs third cladding layer 606 are formed into a stripe-shaped ridge 61 having a width of about 3 μm.
5 (FIG. 6C).

Next, the striped resist mask 617 formed on the p-type GaAs protective layer 607 is removed.
By the second MOCVD method, the p-type GaAs protective layer 6 is formed.
7 and the p-type AlGaAs third cladding layer 606 are embedded on the side surfaces of the ridge 615 with an n-type AlGaAs current block layer 608 and a p-type GaAs planarization layer 609 (FIG. 6).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 615 by using a known photolithography technique.
The planarization layer 609 and the p formed on the ridge 615
Mask 618 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 609, and the n-type AlGaAs current block layer 608 and the p-type GaAs planarization layer 609 at the opening of the resist mask 618 are formed by using a known etching technique. It is selectively removed to form a current non-injection region 614 (FIG. 6E).

Next, the resist mask 618 formed on the p-type GaAs planarization layer 609 is removed, and the third MO
A p-type GaAs contact layer 610 is formed by a CVD method (FIG. 6F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed almost at the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflective film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area at both ends of the light emission of a 800 μm resonator is manufactured. Is done.

The semiconductor laser device obtained by the above-described manufacturing method, and the Zn inside the resonator of the semiconductor laser device of the present invention obtained by the manufacturing method described in the first embodiment.
Depth distribution of atoms in secondary ion mass spectrometer (SIM
It measured in S). FIG. 12 shows the measurement results. The vertical axis is the impurity atom concentration (atoms / cm ³ ), and the horizontal axis is p-type GaAs.
The depth is from the s protective layer 609 (μm). For reference, FIG. 12 also shows the distribution of Zn atoms in the depth direction after the first MOCVD epitaxial growth.

As can be seen from FIG. 12, inside the resonator of the semiconductor laser device obtained by the manufacturing method of Example 1, the Zn atom concentration of each of the layers 4 to 7 exhibiting p-type conductivity is reduced. Although diffusion of Zn atoms to the n-type AlGaAs first cladding layer 2 side is also observed, inside the resonator of the semiconductor laser device obtained by the manufacturing method of this embodiment,
Diffusion of Zn atoms to the n-type AlGaAs first cladding layer 602 side and Zn in each of the layers 604 to 607 exhibiting p-type conductivity
There is almost no decrease in atomic concentration.

The characteristics of the semiconductor laser device obtained by the manufacturing method of this embodiment were measured. For comparison, the characteristics of the semiconductor laser device obtained by the manufacturing method of Example 1 were also measured.

As a result, the oscillation wavelength (λ) at a CW of 120 mW was 785 nm for both the semiconductor laser devices of this embodiment and the first embodiment, and the characteristic temperature (T0) at 60 ° C. of the semiconductor laser device of this embodiment was 130 K. The characteristic temperature (T0) at 60 ° C. of the semiconductor laser device of Example 1 was 100 K, and the semiconductor laser device obtained by the method of manufacturing a semiconductor laser device of the present example was obtained by the manufacturing method of Example 1. It is clear that the temperature characteristics are improved as compared with the semiconductor laser device.

[0128] In the manufacturing method of the semiconductor laser device of this embodiment, the surface of the p-type GaAs protective layer 607 Si _x O _y N
_{A z} (x, y, z is 1 or more) film 616 and a Si _x O _y (x, y is 1 or more) film 623 which is a dielectric film are covered by RT.
Since the annealing by the method A is performed, the p-type GaAs protective layer 6 is formed.
07 can be prevented from re-evaporating from the surface of ZnO.
The diffusion of Zn atoms generated by the re-evaporation of n atoms can be suppressed, and the formation of a remote junction due to the diffusion of Zn atoms toward the n-type AlGaAs first cladding layer 602 can be suppressed, thereby improving the temperature characteristics. Is possible.

In this embodiment, p near the light emitting end face portion is used.
Formed on the surface of the p-type GaAs protective layer 607_xO_yN
_z(X, y, and z are 1 or more) A film 616 and Si_xO_yN_z
(X, y, and z are 1 or more) p where the film 616 is not formed
Type GaAs protective layer 607 as a dielectric film formed on the surface
And Si_xO_y(X and y are 1 or more). _x
O_y, Al_xN_y, Si_xN_y(X and y are 1 or more)
If so, the p-type GaAs protective layer 6 under the dielectric film 623
07, a small amount of vacancy is generated, and this vacancy is Zn
Since atoms are captured, the diffusion of Zn atoms can be suppressed,
To the n-type AlGaAs first cladding layer 602 side
Suppress formation of remote junction due to diffusion of atoms
can do.

[0130] In this _{example, Si x O y N z (} x, y, z
Although the film 616 is formed by using the plasma CVD method, the same effect as described above can be obtained by using the sputtering method. _{Further, Si x O y N z (} x, y, z is 1 or more) of the film 616, on the near region to be a light emitting end face Si _x O
_y (x, y is 1 or more) after forming the film, the Si _x O _{y (x, y}
1 or higher) method of forming by a nitrogen atom is ion-implanted in the film, on a neighboring region as a light emitting end face Si _x
N _z (x, z is 1 or more) after forming the film, the Si _x N _{z (x,}
z is 1 or more) a method of forming the film by ion implantation of oxygen atoms into the film,
The same effect as described above can be obtained by using a method in which oxygen and nitrogen atoms are ion-implanted into the Si film after the film is formed. In the present embodiment, AlGaAs
Although the description has been made with respect to the semiconductor laser based on AlGaInP, similar effects can be obtained with an AlGaInP semiconductor laser. Embodiment 6 A manufacturing method of Embodiment 6 will be described with reference to FIG.
On the n-type GaAs substrate 701, n is sequentially formed by MOCVD.
Type AlGaAs first cladding layer 702, MQW active layer 7
03, a p-type AlGaAs second cladding layer 704, a p-type etching stop layer 705, a p-type AlGaAs third cladding layer 706, and a p-type GaAs protective layer 707 are epitaxially grown.

[0131] Thereafter, the entire surface of the p-type GaAs protective layer 707 surface by a plasma CVD _{method, Si x O y (x,} y
1 or more) film 719 is formed, the Si _x O _{y (x, y} is 1 or more) on the surface of the membrane 719, by photolithography, the width 40μm in the direction perpendicular to the ridge stripe
A resist mask 724 having a stripe-shaped opening is formed. The stripe-shaped opening was formed so as to be over the region near the light-emitting end face, and the pitch of the stripe was 800 μm, which was the same as the resonator length (FIG. 7A). Si _x O _y by plasma CVD (x, y is 1 or more) film formation conditions, as the raw material gas, SiH _4, N ₂ O, and N ₂ using,
The film was formed at a RF power of 15 W, a substrate temperature of 280 ° C. and a film thickness of 5000 °.

Next, p-type GaAs near the light emitting end face is used.
Si formed on the surface of the s protective layer 707 _x O _{y (x, y} is 1 or more) to the membrane 719, ion implantation of nitrogen atoms. Thereby, the surface Si _x O _y N _z of the p-type GaAs protective layer 707 serving as a light emission end surface portion near (x, y, z is 1 or more) film 716 is formed. The ion implantation conditions include an ion acceleration energy of 150 keV and a dose of 1E14c.
m ^-2 . After the ion implantation step, the resist mask 7
By removing only 24, Si for increasing the band gap of the light emitting end surface vicinity region of the MQW active layer 703 than the band gap of the resonator inside the active layer _x O _y N _z
(X, y, z are 1 or more) film 716 and p-type GaAs
A thin film for preventing re-evaporation of Zn atoms from the surface of the protective layer _{707 Si x O y (x,} y is 1 or more) film 719 is formed (FIG. 7 (b)) since, in Example 5 The number of steps can be greatly reduced as compared with the manufacturing method.

Thereafter, annealing by the RTA method is performed.
The annealing conditions at this time are as follows: temperature 750 ° C., temperature rising rate 10
The test was performed at 0 ° C./sec and a holding time of 60 seconds.

[0134] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 71 immediately below film 716
3 and the MQW active layer (active region) 703 inside the resonator, the emission spectrum of the window region 713 is shifted by 40 nm shorter than the emission spectrum of the active region 703. And p-type Ga
Si in As protecting layer 707 surface _x O _{y (x, y} is 1 or more) in the state in which film 719 is not formed was the same as when performing annealing using an RTA method.

[0135] Then, Si was formed on the surface of the p-type GaAs protective layer _{707 x O y N z (x} , y, z is 1 or more) film 7
16 and Si _x O _{y (x, y} is 1 or more) to remove the membrane 719,
P-type GaAs using known photolithography technology
Striped resist mask 717 on protective layer 707
Then, the p-type GaAs protective layer 707 and the p-type AlGaAs third cladding layer 706 are processed into a stripe-shaped ridge 715 having a width of about 3 μm using a known etching technique so as to reach the p-type etching stop layer 705. (FIG. 7C).

Next, the striped resist mask 717 formed on the p-type GaAs protective layer 707 is removed.
By the second MOCVD method, the p-type GaAs protective layer 7 is formed.
07 and a p-type AlGaAs third cladding layer 706 are embedded on the side surfaces of a ridge 715 with an n-type AlGaAs current blocking layer 708 and a p-type GaAs planarization layer 709 (FIG. 7).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 715 by using a known photolithography technique.
Planarization layer 709 and p formed on ridge 715
Mask 718 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 709, and the n-type AlGaAs current block layer 708 and the p-type GaAs planarization layer 709 at the opening of the resist mask 718 are formed by a known etching technique. It is selectively removed to form a current non-injection region 714 (FIG. 7E).

Next, the resist mask 718 formed on the p-type GaAs planarization layer 709 is removed, and the third MO
A p-type GaAs contact layer 710 is formed by a CVD method (FIG. 7F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed substantially at the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

The characteristics of the semiconductor laser device obtained by the manufacturing method of this embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW was 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, the result of the maximum light output test is 300 mW
COD-free even at the above light output, 70 ° C1
A 20 mW reliability test showed that the average life was about 2
500 hours.

Further, the characteristic temperature (T0) at 60 ° C. of the semiconductor laser device obtained by the manufacturing method of the present embodiment and the semiconductor laser device obtained by the manufacturing method of the first embodiment was measured. The semiconductor laser device of the present embodiment is 140K, the semiconductor laser device of the first embodiment is 100K.
It was K.

The semiconductor laser device obtained by the method of manufacturing a semiconductor laser device of this embodiment has a lower driving current and a lower driving voltage than the semiconductor laser device obtained by the manufacturing method of the first embodiment. Voltage and temperature characteristics are improved. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method. The improvement of
The epitaxially grown wafer surface Si _x O _y N
_z (x, y, _z is 1 or more) film 716 and the Si _x O _{y (x, y}
Is one or more).
This is an effect of suppressing formation of a remote junction due to diffusion of Zn atoms to the s-first cladding layer 702 side.

In this embodiment, an AlGaAs semiconductor laser has been described. However, the same effect can be obtained with an AlGaInP semiconductor laser. Example 7 A manufacturing method of Example 7 will be described with reference to FIG.
On the n-type GaAs substrate 801, n is sequentially formed by MOCVD.
Type AlGaAs first cladding layer 802, MQW active layer 8
03, a p-type AlGaAs second cladding layer 804, a p-type etching stop layer 805, a p-type AlGaAs third cladding layer 806, and a p-type GaAs protection layer 807 are epitaxially grown.

[0145] Thereafter, the entire surface of the p-type GaAs protective layer 807 surface by a plasma CVD _{method, Si x N z (x,} z
1 or more) film 820 is formed, the Si _x N _{z (x, z} is 1 or more) on the surface of the membrane 820, by photolithography, the width 40μm in the direction perpendicular to the ridge stripe
A resist mask 824 having a stripe-shaped opening is formed. The stripe-shaped opening was formed so as to be over the region near the light-emitting end face, and the pitch of the stripe was 800 μm, which was the same as the resonator length (FIG. 8A). The conditions for forming a Si _x N _z (x, z is 1 or more) film by plasma CVD are as follows: SiH ₄ , NH ₃ , and N ₂ are used as source gases.
The film was formed at a RF power of 150 W, a substrate temperature of 280 ° C. and a film thickness of 5000 °.

Next, the p-type GaAs near the light emitting end face is used.
Oxygen atoms are ion-implanted into the Si _x N _z (x, z is 1 or more) film 820 formed on the surface of the s protective layer 807. Thereby, the surface Si _x O _y N _z of the p-type GaAs protective layer 807 serving as a light emission end surface portion near (x, y, z is 1 or more) film 816 is formed. As the ion implantation conditions, the ion acceleration energy is 150 keV and the dose is 1E15c.
m ^-2 .

After the ion implantation step, the resist mask 82
By removing only 4, Si _x O _y N for making the band gap in the region near the light emitting end face of the MQW active layer 803 larger than the band gap of the active layer inside the resonator.
_z (x, y, and z are 1 or more) film 816 and p-type GaAs
Since a Si _x N _z (x, z is 1 or more) film 820 is formed as a thin film for preventing re-evaporation of Zn atoms from the surface of the s protective layer 807 (FIG. 8B), the fifth embodiment is performed. The number of steps can be significantly reduced as compared with the manufacturing method of (1).

Thereafter, annealing by the RTA method is performed.
The annealing conditions at this time are as follows: temperature 750 ° C., temperature rising rate 10
The test was performed at 0 ° C./sec and a holding time of 60 seconds.

[0149] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 81 immediately below the film 816
As a result of measuring the wavelengths of the active region 3 and the MQW active layer (active region) 803 inside the resonator, the emission spectrum from the window region 813 is shifted by 50 nm to the shorter wavelength side than the emission spectrum from the active region 803. And p-type Ga
Si in As protecting layer 807 surface _x N _{z (x, z} is 1 or more) in the state in which film 820 is not formed was the same as when performing annealing using an RTA method.

[0150] Then, Si was formed on the surface of the p-type GaAs protective layer _{807 x O y N z (x} , y, z is 1 or more) film 8
16 and Si _x N _{z (x, z} is 1 or more) to remove the membrane 820,
P-type GaAs using known photolithography technology
Striped resist mask 817 on protective layer 807
Then, the p-type GaAs protective layer 807 and the p-type AlGaAs third cladding layer 806 are processed into a stripe-shaped ridge 815 having a width of about 3 μm using a known etching technique so as to reach the p-type etching stop layer 805. (FIG. 8C).

Next, the striped resist mask 817 formed on the p-type GaAs protective layer 807 is removed.
By the second MOCVD method, the p-type GaAs protective layer 8 is formed.
7 is buried with an n-type AlGaAs current block layer 808 and a p-type GaAs planarization layer 809 (FIG. 8).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 815 by using a known photolithography technique.
Planarization layer 809 and p formed on ridge 815
Mask 818 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 809, and the n-type AlGaAs current block layer 808 and the p-type GaAs planarization layer 809 at the opening of the resist mask 818 are formed by using a known etching technique. It is selectively removed to form a current non-injection region 814 (FIG. 8E).

Next, the resist mask 818 formed on the p-type GaAs planarization layer 809 is removed, and the third MO
A p-type GaAs contact layer 810 is formed by a CVD method (FIG. 8F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed almost in the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

The characteristics of the semiconductor laser device obtained by the manufacturing method of this embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW was 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, the result of the maximum light output test is 300 mW
COD-free even at the above light output, 70 ° C1
When a 20 mW reliability test was performed, the average life was about 3
000 hours.

Further, the characteristic temperature (T0) at 60 ° C. of the semiconductor laser device obtained by the manufacturing method of the present embodiment and the semiconductor laser device obtained by the manufacturing method of the first embodiment was measured. The semiconductor laser device of the present embodiment is 140K, the semiconductor laser device of the first embodiment is 100K.
It was K.

The semiconductor laser device obtained by the method for manufacturing a semiconductor laser device of this embodiment has a lower driving current and a lower driving voltage than the semiconductor laser device obtained by the manufacturing method of the first embodiment. Voltage and temperature characteristics are improved. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method. The improvement of
The epitaxially grown wafer surface Si _x O _y N
_z (x, y, _z is 1 or more) film 816 and the Si _x N _{z (x, z}
Is one or more).
This is an effect of suppressing formation of a remote junction due to diffusion of Zn atoms to the s-first cladding layer 802 side.

In this embodiment, an AlGaAs semiconductor laser has been described. However, similar effects can be obtained with an AlGaInP semiconductor laser. Example 8 A manufacturing method of Example 8 will be described with reference to FIG.
On the n-type GaAs substrate 901, n is sequentially formed by MOCVD.
AlGaAs first cladding layer 902, MQW active layer 9
03, a p-type AlGaAs second cladding layer 904, a p-type etching stop layer 905, a p-type AlGaAs third cladding layer 906, and a p-type GaAs protection layer 907 are epitaxially grown.

Thereafter, a Si film 921 (thickness 5000 °) is formed on the entire surface of the p-type GaAs protective layer 907 by an electron beam evaporation method, and the surface of the Si film 921 is
A resist mask 924 having a 40 μm-wide stripe-shaped opening in a direction orthogonal to the ridge stripe is formed by photolithography. The stripe-shaped opening is formed so as to be on a region near the light emitting end face (FIG. 9A).

Thereafter, the p-type Ga in the vicinity of the light-emitting end face is obtained.
The Si film 921 formed on the surface of the As protective layer 907 includes
Ion implantation of nitrogen atoms is performed, followed by ion implantation of oxygen atoms. Thereby, p near the light emitting end face portion is obtained.
On the surface of the mold GaAs protective layer _{907 Si x O y N z (} x,
(y and z are 1 or more) A film 916 is formed. The conditions for ion implantation of nitrogen atoms are as follows:
keV and a dose amount of 1E14 cm ^-2. The ion implantation conditions of oxygen atoms are as follows.
The test was performed at 0 keV and a dose of 1E15 cm ⁻² .

After the ion implantation step, a resist mask 92 is formed.
By removing only 4, Si _x O _y N for increasing the band gap in the region near the light emitting end face of the MQW active layer 903 to be larger than the band gap of the active layer inside the resonator.
_z (x, y, and z are 1 or more) film 916 and p-type GaAs
An Si film 921 which is a thin film for preventing re-evaporation of Zn atoms from the surface of the s protective layer 907 is formed (FIG. 9B).
Therefore, the number of steps can be significantly reduced as compared with the fifth embodiment.

Thereafter, annealing by the RTA method is performed.
The annealing conditions at this time are as follows: temperature 750 ° C., temperature rising rate 10
The test was performed at 0 ° C./sec and a holding time of 60 seconds.

[0164] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
Is 1 or more) MQW active layer (window region) 91 immediately below film 916
3 and the MQW active layer (active region) 903 inside the resonator, the emission spectrum from the window region 913 was shifted by 60 nm to the shorter wavelength side than the emission spectrum from the active region 903. And p-type Ga
In the state where the Si film 921 is not formed on the surface of the As protective layer 907, the same as the case where the annealing using the RTA method is performed.
Si _x O _y N formed on the surface of the aAs protective layer 907
_z (x, y, and z are 1 or more) film 916 and Si film 92
1 is removed and using a known photolithography technique
A stripe-shaped resist mask 917 is formed on the p-type GaAs protective layer 907, and the p-type GaAs protective layer 907 and the p-type AlGaAs third cladding are formed by a known etching technique so as to reach the p-type etching stop layer 905. The layer 906 is formed into a stripe-shaped ridge 91 having a width of about 3 μm.
5 (FIG. 9C).

Next, the striped resist mask 917 formed on the p-type GaAs protective layer 907 is removed.
By the second MOCVD method, the p-type GaAs protective layer 9 is formed.
07 and a p-type AlGaAs third cladding layer 906, the side surface of the ridge 915 is filled with an n-type AlGaAs current block layer 908 and a p-type GaAs planarization layer 909 (FIG. 9).
(D)).

Thereafter, the p-type GaAs formed on the side surface of the ridge 915 by using a known photolithography technique.
The planarization layer 909 and the p formed on the ridge 915
Mask 918 is formed in the vicinity of the light emitting end face of the n-type GaAs planarization layer 909, and the n-type AlGaAs current block layer 908 and the p-type GaAs planarization layer 909 at the opening of the resist mask 918 are formed by using a known etching technique. It is selectively removed to form a current non-injection region 914 (FIG. 9E).

Next, the resist mask 918 formed on the p-type GaAs planarization layer 909 is removed, and the third MO
A p-type GaAs contact layer 910 is formed by a CVD method (FIG. 9F). Furthermore, the upper surface is a p-electrode, and the lower surface is n-electrode.
Form electrodes.

Next, a scribe line is placed substantially in the center of the window region having a width of 40 μm, and the cavity is divided into bars in the length of the cavity to form a cavity. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

The characteristics of the semiconductor laser device obtained by the manufacturing method of the present embodiment were measured.

As a result, the oscillation wavelength (λ) at a CW of 120 mW was 785 nm, and the driving current (I
op) is a drive voltage (V) at 150 mA and CW 120 mW.
op) is 2.0 V, the result of the maximum light output test is 300 mW
COD-free even at the above light output, 70 ° C1
A 20 mW reliability test showed that the average life was about 4
000 hours.

Further, the characteristic temperature (T0) at 60 ° C. of the semiconductor laser device obtained by the manufacturing method of the present embodiment and the semiconductor laser device obtained by the manufacturing method of the first embodiment was measured. The semiconductor laser device of the present embodiment is 140K, the semiconductor laser device of the first embodiment is 100K.
It was K.

The semiconductor laser device obtained by the method for manufacturing a semiconductor laser device of the present embodiment has a lower driving current and a lower driving voltage than the semiconductor laser device obtained by the manufacturing method of the first embodiment. Voltage and temperature characteristics are improved. The lowering of the driving current and the lowering of the driving voltage are the effects of reducing the diffusion of Zn atoms into the MQW active layer inside the resonator by lowering the annealing temperature by the RTA method. The improvement of
The epitaxially grown wafer surface Si _x O _y N
By covering with a _z (x, y, z is 1 or more) film 916 and a Si film 921, the n-type AlGaAs first cladding layer 902 is formed.
This is an effect of suppressing formation of a remote junction due to diffusion of Zn atoms to the side.

In this embodiment, an AlGaAs semiconductor laser has been described. However, the same effect can be obtained with an AlGaInP semiconductor laser. Ninth Embodiment FIG. 15 is a sectional view showing the structure of a semiconductor laser device according to a ninth embodiment. 15A is a perspective view including a light emitting end face, FIG. 15B is a cross-sectional view of the waveguide taken along the line Ia-Ia ′ in FIG. 15A, and FIG. I
It is sectional drawing of the layer thickness direction in the b 'line. Also, 110
1 is an n-type GaAs substrate, 1102 is an n-type AlGaAs first
A cladding layer 1103 is an active layer (MQW active layer) in which a multiple quantum well structure in which barrier layers and well layers are alternately stacked is sandwiched between optical guide layers, and 1104 is a p-type AlGaAs.
The second cladding layer, 1105 is a p-type etching stop layer, 1106 is a p-type AlGaAs third cladding layer composed of a ridge stripe in the resonator direction, 1107 is p-type Ga
An As protective layer 1108 is an n-type AlGaAs current blocking layer formed so as to bury the side surface of the p-type AlGaAs third cladding layer composed of a ridge stripe, and 1109 is a p-type AlGaAs current blocking layer.
1111 denotes a p-type GaAs contact layer, 1111 denotes a p-side electrode, and 1112 denotes an n-side electrode. Further, 1113 _{Si x O y N z (x} , y, z is 1 or more) greater area than the band gap energy of the MQW active layer right under film inside the resonator of the MQW active layer 1103 (window area ), 1115 is p
-Type AlGaAs third cladding layer 1106 and p-type GaAs
Stripe-shaped ridge 111 composed of a protective layer 1107
6 is Si _x O _y N _z formed in a stripe shape in a direction perpendicular to the ridge stripe (x, y, z is 1 or more) is a membrane.

Next, a manufacturing method will be described with reference to FIG. MOCV is sequentially formed on an n-type GaAs substrate 1101.
An active layer (MQW active layer) 1 in which a multiple quantum well structure in which an n-type AlGaAs first cladding layer 1102, a barrier layer, and a well layer are alternately stacked by an optical guide layer is formed by the D method.
103, p-type AlGaAs second cladding layer 1104, p
The type etching stop layer 1105, the p-type AlGaAs third cladding layer 1106, and the p-type GaAs protective layer 1107 are epitaxially grown (FIG. 16A).

Thereafter, the p-type Ga in the vicinity of the light-emitting end face is obtained.
On the surface of As protective layer 1107, by the plasma CVD method and the photolithography method, the width 40μm stripe in a direction perpendicular to the ridge stripe, Si _x O _y N
_{A z} (x, y, z is 1 or more) film 1116 is formed. According to the plasma _{CVD Si x O y N z (} x, y, z is 1 or more)
The conditions for forming the film are as follows: SiH ₄ , N ₂ O, N ₂
Using an RF power of 100 W and a substrate temperature of 280 ° C.
It was formed with a thickness of 00 °. The stripe pitch was 800 μm, which is the same as the resonator length (FIG. 16B).

Next, annealing by the RTA method is performed. The annealing conditions at this time are a temperature of 950 ° C. and a temperature rising rate of 100 ° C.
/ Sec and a holding time of 20 seconds.

[0177] using a portion of the wafer after annealing by the RTA method at PL _{method, Si x O y N z (} x, y, z
1 or more) MQW active layer (window region) 1 immediately below the film 1116
113 and MQW active layer (active region) 110 inside the resonator
As a result of measuring each wavelength of No. 3, the emission spectrum from the window region 1113 was shifted by 30 nm to a shorter wavelength side than the emission spectrum from the active region 1103.

[0178] Then, Si was formed on the surface of the p-type GaAs protective layer 1107 serving as the light emission end surface portion near _x O _y N
_z (x, y, z is 1 or more) while leaving the film 1116, using a known photolithography technique, Si _x O _y N _z
(X, y, and z are 1 or more) Striped resist mask 1117 on film 1116 and p-type GaAs protective layer 1107
It is formed and by using a known etching technique, Si so as to reach the p-type etching stop layer 1105 _x O _y N _z
(X, y, and z are 1 or more) A film 1116, a p-type GaAs protective layer 1107, and a p-type AlGaAs third cladding layer 1106
Is processed into a stripe-shaped ridge 1115 having a width of about 3 μm (FIG. 16C).

[0179] _{Then, Si x O y N z (} x, y, z is 1 or more) film 1116 and the p-type GaAs protective layer 1107 stripe-shaped resist mask 1117 formed on removal, the second MOCVD The p-type GaAs protective layer 1107 and the p-type AlGaAs third cladding layer 1106 are formed by a method.
The side surface of the ridge 1115 is embedded with an n-type AlGaAs current blocking layer 1108 and a p-type GaAs planarization layer 1109 (FIG. 16D).

Thereafter, the p-type GaAs formed on the side surface of the ridge 1115 by using a known photolithography technique.
A resist mask 1118 is formed on the s planarization layer 1109, and the resist mask 1118 is formed using a known etching technique.
118 n-type AlGaAs current blocking layer 110 with opening
8 and the p-type GaAs planarization layer 1109 are selectively removed (FIG. 16E).

Next, the resist mask 1118 formed on the p-type GaAs planarization layer 1109 is removed, and a p-type GaAs contact layer 1110 is formed by a third MOCVD method (FIG. 16F). Furthermore, the p electrode 11 is provided on the upper surface.
11, an n-electrode 1112 is formed on the lower surface.

Next, a scribe line is placed substantially in the center of the window region having a width of 40 μm, and the cavity is divided into bar lengths to form a resonator. Finally, the light emission on both sides of the bar is coated with a reflection film, and further divided into chips, and an element having a window area of about 20 μm and a current non-injection area on both ends of the light emission of an 800 μm resonator is manufactured. Is done.

In the semiconductor laser of this embodiment, the surface of the p-type GaAs protective layer 1107 near the light-emitting end face is coated with Si _x
The step of forming the O _y N _z (x, y, z is 1 or more) film 1116 also serves as a step of forming a current non-injection region, so that the number of steps can be reduced. Since the formed Si _x O _y N _z (x, y, z is 1 or more) film 1116 also serves as a current non-injection region, the window region 1113 is located immediately below the current non-injection region, and there is no displacement. Since current injection into the region is prevented and carrier loss due to the presence of vacancy defects in the window region can be suppressed, the reactive current that does not contribute to light emission is reduced.

The characteristics of the semiconductor laser device obtained by the manufacturing method of the present embodiment were measured.

As a result, the oscillation wavelength (λ) at CW 120 mW was 785 nm, and the driving current (I
op) is a driving voltage (V) at 170 mA and a CW of 120 mW.
op) is 2.1 V, the result of the maximum light output test is 300 mW
COD-free even at the above light output, 70 ° C1
A 20 mW reliability test showed that the average life was about 2
000 hours.

[0186] In this _{example, Si x O y N z (} x, y, z
The film 1116 is formed by using the plasma CVD method, but the same effect as described above can be obtained by using the sputtering method. _{Further, Si x O y N z (} x, y, z is 1 or more)
The film 1116, on the region near the light emission facet Si _x O _y
(X, y is 1 or more) after forming the film, the Si _x O _y (x, y is 1 or more) a method of forming by ion implantation of nitrogen atoms in the film, on a neighboring region as a light emitting end face Si _x N _z
(X, z is 1 or more) after forming the film, the Si _x N _z (x, z is 1 or more) a method of forming by ion implantation of oxygen atoms in the film, on a neighboring region as a light emitting end face The same effect as described above can be obtained by using a method of forming an Si film by ion-implanting oxygen atoms and nitrogen atoms into the Si film.

In this embodiment, an AlGaAs semiconductor laser has been described. However, similar effects can be obtained with an AlGaInP semiconductor laser.

[0188]

As described above, according to the present invention, Si
_{x O y N z (x,} y, z is 1 or more) film, and annealing the layered structure formed by the epitaxial growth, the _{Si x O y N z (x} , y, z is 1 or more) film A hole is generated underneath, and the hole is diffused to reach the active layer and is disordered, so that the band gap of the active layer in the vicinity of the light emitting end face is reduced to the band gap of the active layer inside the resonator. As a result, the diffusion of impurities such as Zn atoms into the active layer can be suppressed by shortening the annealing time, and the active layer in the vicinity of the light-emitting end face is more effectively made to have a forbidden band width than the active layer inside the resonator. Since a wide window region can be formed, the driving current and voltage at the time of high output are reduced, and there is an effect that a semiconductor laser device excellent in long-term reliability in high output driving can be obtained.

As described in the present invention, after disordering, Si
_x O _y N _z (x, y, z is 1 or more) film is removed, and the second
By forming a ridge-shaped stripe on the conductive-type upper cladding layer and the second-conductive-type protective layer, the ridge-shaped stripe has almost no variation in the wafer surface, and the first conductive-type current formed on the side surface of the ridge-shaped stripe. Since a constriction layer having a very good crystallinity can be obtained, there is an effect that a semiconductor laser device having no leakage current and excellent in long-term reliability in high-output driving can be obtained with high yield.

Further, as in the present invention, the method further includes the step of forming a current non-injection region in the region near the end face of the laser cavity, thereby preventing an increase in the number of production steps due to the formation of the current non-injection region. The non-injection region prevents current injection into the window region, suppresses carrier loss due to the presence of vacancies in the window region, and reduces reactive current that does not contribute to light emission. There is an effect that a semiconductor laser device having excellent long-term reliability in high output driving can be obtained.

On the other hand, as in the present invention, after disordering, SixO
By leaving the yNz film in the device without removing it, there is no need to form a current non-injection region again, preventing an increase in the number of production steps due to the formation of the current non-injection region, and the positions of the window region and the current non-injection region. Since no displacement occurs, the current non-injection region prevents current injection into the window region, suppresses carrier loss due to the presence of vacancy defects in the window region, and reduces reactive current that does not contribute to light emission. The driving current at the time of high output is reduced, and there is an effect that a semiconductor laser device excellent in long-term reliability in high output driving can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a structure of a semiconductor laser device according to a first embodiment.

FIG. 2 is an explanatory diagram of a method for manufacturing the semiconductor laser device of Example 1.

FIG. 3 is an explanatory diagram of a method for manufacturing a semiconductor laser device of Example 2.

FIG. 4 is an explanatory diagram of a method for manufacturing a semiconductor laser device of Example 3.

FIG. 5 is an explanatory diagram of a method for manufacturing a semiconductor laser device of Example 4.

FIG. 6 is an explanatory diagram of the method for manufacturing the semiconductor laser device of the fifth embodiment.

FIG. 7 is an explanatory diagram of a method for manufacturing a semiconductor laser device of Example 6.

FIG. 8 is an explanatory diagram of the method for manufacturing the semiconductor laser device of the seventh embodiment.

FIG. 9 is an explanatory diagram of a method for manufacturing a semiconductor laser device of Example 8.

FIG. 10 shows the relationship between the annealing time by RTA and the wavelength shift amount of the window region with respect to the wavelength of the active region.

FIG. 11 shows the relationship between the annealing temperature by the RTA method and the wavelength shift amount of the window region with respect to the wavelength of the active region.

FIG. 12 is a depth direction distribution of Zn atoms inside a resonator of a semiconductor laser device.

FIG. 13 is a cross-sectional view showing the structure of a conventional semiconductor laser device.

FIG. 14 is an explanatory view of a conventional method for manufacturing a semiconductor laser device.

FIG. 15 is a sectional view showing a structure of a semiconductor laser device of Example 9;

FIG. 16 is an explanatory diagram of the method for manufacturing the semiconductor laser device of the ninth embodiment.

[Explanation of symbols]

1,301,401,501,601,701,80
1,901,1001,1101... N-type GaAs substrate 2,302,402,502,602,702,80
2,902,1102... N-type AlGaAs first cladding layer 3,303,403,503,603,703,80
3,903,1103... MQW active layer 4,304,404,504,604,704,80
4,904,1104... P-type AlGaAs second cladding layer 5,305,405,505,605,705,805
5,905,1105 ... p-type etching stop layer 6,306,406,506,606,706,80
6,906,1106... P-type AlGaAs third cladding layer 7,307,407,507,607,707,80
7,907,1107... P-type GaAs protective layer 8,308,408,508,608,708,80
8,908,1108... N-type AlGaAs current blocking layer 9,309,409,509,609,709,80
9,909,1109 ... p-type GaAs planarization layer 10,310,410,510,610,710,81
0,910,1005,1110... P-type GaAs contact layer 11,311,411,511,611,711,81
1,911,1009,1111... P-type electrode 12,312,412,512,612,712,81
2,912,1008,1112... N-type electrode 13,313,413,513,613,713,81
3,913,1113 ... window area 14,314,414,514,614,714,81
4,914... Current non-injection region 15,315,415,515,615,715,81
5,915,1115 ・ ・ ・ Striped ridges 16,316,416,516,616,716,81
_{6,916,1116 ··· Si x O y N z} (x, y, z
Is 1 or more) membrane 17, 18, 317, 318, 417, 418, 51
7,518,617,618,717,718,72
4,817,818,824,917,918,92
4,1011,1117,1118 ... resist mask 319,719 ··· Si _x O _y film (x, y 1 or more) 420,820 ··· Si _x N _z film (x, z is 1 or more) 521, 921: Si film 322, 422, 522: protective film 623: dielectric film 1002: n-type AlGaAs lower cladding layer 1003: quantum well active layer 1003a: quantum well activity Region contributing to laser oscillation of layer 1003b ... window structure region formed near the laser resonator end face of quantum well active layer 1004a ... p-type AlGaAs first upper cladding layer 1004b ... p-type AlGaAs second Upper cladding layer 1006: hole diffusion region 1007: proton injection region 1010: SiO ₂ film 1020: laser cavity end face

Claims (12)

[Claims] 1. A laser resonator end face when a semiconductor laser device having a laminated structure including a lower cladding layer, an active layer, and an upper cladding layer is formed on a substrate using a compound semiconductor containing at least gallium. After forming a SixOyNz film (x, y, and z are 1 or more; the same applies hereinafter) above the stacked structure near a region, annealing is performed to generate holes under the SixOyNz film, A method for manufacturing a semiconductor laser device, characterized in that the holes are diffused until they reach the active layer, and the active layer in the vicinity of the laser cavity end face is disordered. 2. A laser resonator end face when a semiconductor laser device comprising a laminated structure including a lower cladding layer, an active layer, and an upper cladding layer on a substrate using a compound semiconductor containing at least gallium. After forming a SixOyNz film above the stacked structure near the region and forming a dielectric film on the upper surface of the stacked structure including the SixOyNz film, annealing is performed.
A semiconductor, wherein holes are generated under the SixOyNz film, and the holes are diffused until the holes reach the active layer, and the active layer is disordered in the vicinity of a region serving as an end face of the laser resonator. Laser element manufacturing method. 3. A method of manufacturing a semiconductor laser device having a laminated structure including a lower clad layer, an active layer, and an upper clad layer on a substrate using a compound semiconductor containing at least gallium. Among silicon, oxygen and nitrogen,
Forming a film containing at least silicon; and ion-implanting oxygen atoms and / or nitrogen atoms in the vicinity of the region of the film containing at least silicon which is to be a laser cavity end face to form a SixOyNz film, followed by annealing. Performing a step of generating vacancies under the SixOyNz film, diffusing the vacancies until reaching the active layer, and disordering the active layer in the vicinity of the laser cavity end face. A method of manufacturing a semiconductor laser device, comprising: 4. The method according to claim 1, wherein the SixOyNz film is formed by implanting nitrogen atoms into the SixOy film. 5. The method according to claim 1, wherein the SixOyNz film is formed by ion-implanting oxygen atoms into the SixNy film. 6. The method according to claim 1, wherein the SixOyNz film is formed by implanting nitrogen atoms and oxygen atoms into a Si film. . 7. An active layer having a multi-quantum well structure in which at least a first conductivity type clad layer, a barrier layer, and a well layer are alternately stacked on a first conductivity type semiconductor substrate by an optical guide layer. And a step of sequentially epitaxially growing a cladding layer of the second conductivity type; and a step of forming a SixOyNz film near the region of the epitaxially grown layer that is to be a light emitting end face, and annealing.
The method for manufacturing a semiconductor laser device according to claim 1, wherein the method comprises: 8. An active layer in which a multiple quantum well structure in which at least a first conductivity type clad layer, a barrier layer and a well layer are alternately stacked on a first conductivity type semiconductor substrate is sandwiched by an optical guide layer. Sequentially epitaxially growing a lower cladding layer of the second conductivity type, an etching stop layer of the second conductivity type, an upper cladding layer of the second conductivity type, and a protective layer of the second conductivity type; Forming a SixOyNz film in the vicinity of a region to be an emission end face and annealing; and, after removing the SixOyNz film, a ridge in a resonator direction on the second conductive type upper cladding layer and the second conductive type protective layer. Forming a stripe-shaped stripe structure, a second-conductivity-type protective layer left by the above-described process, and a first-conductivity-type current confinement layer on the second-conductivity-type etching stop layer exposed by the process. The method of manufacturing a semiconductor laser device according to any one of claims 1 to 6, characterized by comprising a step of epitaxially growing, a. 9. The method for manufacturing a semiconductor laser device according to claim 8, wherein after the first conductivity type current confinement layer is epitaxially grown,
A method for manufacturing a semiconductor laser device, comprising a step of removing a region of the first conductivity type current confinement layer formed on a second conductivity type protection layer, excluding a region near a light emitting end face. 10. An active layer having a multi-quantum well structure in which at least a first conductivity type clad layer, a barrier layer, and a well layer are alternately stacked on a first conductivity type semiconductor substrate by an optical guide layer; A step of sequentially epitaxially growing a lower cladding layer of the second conductivity type, an etching stop layer of the second conductivity type, an upper cladding layer of the second conductivity type, and a protective layer of the second conductivity type; and light emission of the epitaxially grown layer Forming a SixOyNz film in the vicinity of the region to be the end face and annealing; and forming a ridge in the resonator direction on the second conductive type upper clad layer and the second conductive type protective layer while leaving the SixOyNz film. Forming a stripe-shaped stripe structure, a second conductivity type protection layer left by the process, and a first conductivity type current confinement on the second conductivity type etching stop layer exposed by the process. The method of manufacturing a semiconductor laser device according to any one of claims 1 to 6, comprising the steps of epitaxially growing, characterized by comprising a. 11. A laminated structure including at least a lower clad layer, an active layer, and an upper clad layer formed on a substrate, and formed near a region to be a laser cavity end face above the laminated structure. A semiconductor laser device comprising: a SixOyNz film, wherein the band gap of the active layer is smaller inside the resonator than below the SixOyNz film. 12. A multiple quantum well structure formed on a semiconductor substrate of a first conductivity type, in which at least a first conductivity type clad layer, a barrier layer and a well layer are alternately stacked, with an optical guide layer interposed therebetween. An active layer, a second conductivity type lower cladding layer,
A second conductivity type upper cladding layer having a ridge-shaped stripe in the resonator direction, a first conductivity type current confinement layer formed to bury the side surface of the ridge-shaped stripe, and a second
A second conductive type protective layer formed on the conductive type upper cladding layer, wherein a (111) plane is formed on the second conductive type protective layer in the vicinity of a region to be a light emitting end face. And the (1-1-1) plane
A semiconductor laser device in which a conductive type epitaxial growth layer is formed and a band gap of an active layer near a region to be a light emitting end face is larger than a band gap inside an active layer inside a resonator.