JPH09307195A - Method for manufacturing semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method for manufacturing a semiconductor element capable of being disordered in only a super-lattice layer at a desired location with precision by a relatively simple process in which the entire is in a heating furnace, etc., without heating for a long period. SOLUTION: Only a region where a semiconductor laminated material 21 is disordered is heated in a short time without using a dielectric film, etc., For this reason, a light irradiation from a light source 25 having a shorter wavelength than the maximum band gap wavelength of a semiconductor super- lattice structure which is desired to establish non-order and a longer wavelength than a band gap wavelength of the other semiconductor layers stacking this semiconductor super-lattice structure is used. A shield plate 22 for shielding partially the light irradiation is arranged between light passages of a heating light source 25 and a semiconductor laminated material 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device having a quantum well active layer.

[0002]

2. Description of the Related Art Generally, heat treatment of a semiconductor superlattice such as a multi-quantum well layer at a high temperature causes diffusion of atoms at the interface of the semiconductor superlattice, resulting in loss of composition steepness at the heterointerface. . The disordering of a semiconductor superlattice causes a compositional change at the interface, which causes the superlattice to have different properties than originally designed. For this reason, disorder was initially thought to be deterioration, but research has progressed in recent years,
There is a tendency to actively use disorder.

As an example of positively utilizing disordering, for example, in a semiconductor laser having a quantum well active layer, the entire wafer is placed in a heating furnace and the quantum well active layer is disordered by heat treatment, and a low loss waveguide or There is an example of a modulator.

This example will be described. The band structure of the quantum well active layer before disordering is shown by dotted lines 101 and 10 in FIG.
Indicated by 2. The band structure when the quantum well active layer is disordered by heat treatment is shown by solid lines 103 and 104 in FIG.
Indicated by When disorder occurs, the band structure changes due to interdiffusion of atoms between the well layer and the barrier layer. Therefore, the lowest quantum rank of the quantum well changes as the disordering progresses, and the band gap energy wavelength shifts to the short wavelength side.

One of application examples is a laser with a waveguide in which only a partial region is disordered, a non-disordered part is processed as a semiconductor laser, and the disordered part is processed as an optical waveguide connected to the semiconductor laser. . In this case, the disordered portion becomes a waveguide that does not absorb the light of the semiconductor laser and guides it with low loss due to the shortening of the bandgap energy wavelength, so that the light can be routed for a long distance. Various forms such as a confluencer and a shunt can be realized.

Another application example is to process the disordered portion as a semiconductor laser and the undisturbed portion as an absorption modulator.

Although there are various applications as described above, in order to effectively utilize the disordering phenomenon, it is necessary to selectively disorder some regions of the quantum well and process it into an integrated device. When the quantum well structure of the entire device is disordered and processed into a discrete device, the meaning of disordering cannot be found so much. The quantum well structure may be designed so that disordering is not necessary from the beginning.

Several region limiting process methods for disordering the quantum well structure in only a partial region of the device have been reported so far. In one example, when a semiconductor crystal including a quantum well structure is covered with a dielectric material, the degree of disordering changes depending on the presence or composition of the dielectric material.

For example, a partial region of a semiconductor material having an InGaAs / InP superlattice structure is covered with silicon oxide,
When heated at an appropriate temperature for an appropriate time, interlayer diffusion occurs in the lower part of the portion covered with silicon oxide and disordering of the quantum well occurs, whereas interlayer diffusion occurs in the lower part of the portion not covered with silicon oxide. It doesn't progress that much and there isn't much disorder. Therefore, by controlling the coating shape of silicon oxide, it is possible to control the region in which the quantum well is disordered by heating.

[0010]

However, the conventional disordering method causes some problems because the whole semiconductor material has to be heat-treated for a long time.

One is crystal damage given to semiconductor materials. In a semiconductor material, particularly a compound semiconductor material forming a quantum well structure, atoms or molecules having a high vapor pressure are desorbed from the surface during heating. Desorption of atoms or molecules from the surface damages the crystal and significantly reduces the performance of electronic devices containing semiconductor materials. Thus, desorption of atoms from the semiconductor surface due to long-term heat treatment deteriorates the characteristics of the semiconductor device.

Second, there is a limit to the precision of disordering that limits the area. As described above, it is possible to limit the disordered region of the quantum well structure by covering a partial region of the semiconductor surface with a dielectric film such as silicon oxide when it is disordered by heat treatment for a long time. However, the heat treatment causes crystal lattice defects and impurities to act as promoters in the regions where it is not desired to be disordered to cause some atomic diffusion, thereby promoting disordering.

Third is the increase of crystal defects. In the conventional disordering method, the wafer has to be treated at a high temperature for a long time, which may increase crystal defects.

The fourth is relaxation of strain in the strained superlattice. The strained superlattice utilizes the stress due to the difference in lattice constant at the hetero interface. However, when the disordering progresses slightly even in the region where heat treatment is not desired, the steepness of the composition change at the hetero interface is lost, and the lattice constant changes gently with it, which reduces the stress. The strain is relaxed and the characteristics of the semiconductor element are changed.

In addition to the heat treatment process, the following problems occur. First, the number of steps is increased and the entire steps are complicated. In the process, the step of forming a dielectric film on the surface of the semiconductor material, the step of forming a pattern on the dielectric film with a photoresist, the dielectric film is etched using the photoresist as a mask, and the dielectric film is applied only in a predetermined area. Since the steps of leaving, removing the photoresist, and removing the dielectric film after the heat treatment are added, the number of steps increases. If the number of steps is increased due to the additional work of the capping process using the dielectric film, the yield of products is reduced, which is not preferable.

Secondly, defects may occur in the crystal during the process of forming and removing the dielectric film. These include crystal defects caused by heating of the semiconductor material during film formation of the dielectric film or electromagnetic waves generated by the film forming apparatus, and crystal defects caused by stress generated between the dielectric film and the semiconductor material.

Therefore, an object of the first invention according to the present application is, in a method for disordering a semiconductor superlattice active layer or the like, by using light irradiation, light shielding by a mask, and selection of an appropriate light source wavelength, the entire heating furnace, etc. It is an object of the present invention to provide a method for manufacturing a semiconductor device capable of precisely disordering only a superlattice layer at a desired position by a relatively simple process without heating for a long time.

A second object of the present invention is to provide a desired position by disordering the strained quantum well active layer and the like to alleviate strain by light irradiation, light shielding by a mask, and selection of an appropriate light source wavelength. Another object of the present invention is to provide a method for manufacturing a semiconductor device capable of relaxing disorder by precisely disordering only the strained quantum well active layer and the like.

A third object of the present invention is to provide a mask structure that effectively shields light irradiation partially.

The fourth, fifth and sixth inventions according to the present application are, respectively, by using the above method, a semiconductor laser array with a merging waveguide, an optical modulator integrated type semiconductor laser, and an oscillation which are stable and have good performance. It is an object of the present invention to provide a method for manufacturing a semiconductor laser capable of switching polarization modes.

[0021]

Therefore, the present invention solves the above problems by providing means for heating only a region of a semiconductor laminated material to be disordered in a short time without using a dielectric film or the like. .

Specifically, as a heating means, a light source having a wavelength shorter than the bandgap wavelength of the semiconductor superlattice structure to be disordered and longer than the bandgap wavelengths of other semiconductor layers on which this semiconductor superlattice structure is laminated. Light irradiation from is used. As a region limiting means, a mask that partially blocks or reflects light irradiation is installed between the heating light source and the optical path of the semiconductor laminated material. That is, the first according to the present application
The method for manufacturing a semiconductor device according to the invention of claim 1, wherein the semiconductor layered material having a semiconductor superlattice structure is irradiated with light from a light source, and the semiconductor superlattice structure is heated by absorption of light from the light source to disorder the semiconductor superlattice structure. In the method for manufacturing a semiconductor device including, the light source wavelength is shorter than the longest bandgap energy wavelength of the semiconductor superlattice structure, and longer than the bandgap energy wavelength of another semiconductor layer stacked on the semiconductor superlattice structure, By placing a light shielding plate that partially shields the light source light between the light source and the semiconductor laminated material and adjusting the position of the light shielding plate, it is possible to adjust the light source light irradiation position on the semiconductor laminated material. It is characterized by being.

The semiconductor device manufacturing method of the second invention according to the present application is the above manufacturing method, wherein the semiconductor superlattice structure has a lattice constant between semiconductor thin film layers constituting the semiconductor superlattice structure before heating. The stress-strain caused by the disagreement of the above is included and the semiconductor superlattice structure is disordered, so that the steep disagreement of the lattice constants at the interface of the semiconductor thin film layer is eliminated and the stress-strain is relaxed.

The method of manufacturing a semiconductor device according to a third aspect of the present application is the method of manufacturing as described above, wherein the light-shielding plate is a reflection plate in which a carrier that transmits the light source light is provided with a mirror surface portion that reflects the light source light. It is characterized in that it is possible to adjust the light source light irradiation position on the semiconductor laminated material by adjusting the position of the mirror surface portion. In this structure, unnecessary light is reflected by the mirror surface portion (that is, light is not shielded by absorption), so the light shield plate does not have much heat,
The distance between the semiconductor laminated material and the light shielding plate need not be too sensitive.

A method of manufacturing a semiconductor device according to a fourth invention of the present application is a method of manufacturing a semiconductor laser array with a merging waveguide, and a plurality of semiconductors are prepared by adjusting the position of the light shielding plate. The laser portion is not heated, but only the semiconductor superlattice active layer in the merging waveguide portion connected to the emission end of each semiconductor laser is heated.

The fifth aspect of the present invention is a method for producing a semiconductor device, which is a method for producing an optical modulator integrated semiconductor laser, in which the position of the light shielding plate is adjusted to adjust the semiconductor laser portion. It is characterized in that heating is not performed and only the semiconductor superlattice active layer of the optical modulator portion connected to the emission end of the semiconductor laser is heated.

The method of manufacturing a semiconductor device according to the sixth invention of the present application is a method of manufacturing a semiconductor laser capable of switching an oscillating polarization mode, and the tensile strain is adjusted by adjusting the position of the light shielding plate. It is characterized in that the quantum well active layer is partially heated.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment In this embodiment, a method for producing a merged waveguide integrated semiconductor laser array by partially disordering a superlattice active layer of a semiconductor laser to form a low loss waveguide of the semiconductor laser. An example is given.

FIG. 1 shows the final layer structure of the semiconductor laser of this embodiment. The disordering due to heating is caused by the transition of crystal defects in the semiconductor. Since the crystal defect density is highest at the outermost surface of the semiconductor crystal, in order to cause disorder by heating for a short time, it is desirable to position the layer to be disordered at a position relatively close to the surface of the crystal. In this case, the upper layer may be laminated and processed after disordering.

As shown in FIG. 1, for example, this semiconductor laser has InG on an InP substrate 11 having a first conductivity type.
An optical waveguide layer 12 having a composition of aAsP (bandgap wavelength 1.15 μm) is laminated to a thickness of 0.1 μm, and a multiple quantum well active layer 13 is laminated thereon. As the well layers of the multiple quantum well active layer 13, In _0.53 Ga _0.47 As is 6 nm each.
Five layers with a thickness of InGaAsP (bandgap wavelength 1.15 μm) were sandwiched between the well layers with a thickness of 10 nm as a barrier layer. InGaAsP (bandgap wavelength 1.15 μm) optical waveguide layer 14 is laminated thereon to a thickness of 0.1 μm, and is partially heat-treated.

However, the final layer structure (InP clad layer 15, InGaAs cap layer 1) shown in FIG.
After manufacturing up to 6), heat treatment may be performed. In that case, the heat treatment temperature may be raised to some extent or the heat treatment time may be lengthened. This is because, due to the above-mentioned crystal defect density, in order to cause disorder to the same degree, it is necessary to make the temperature higher or the heat treatment time longer than in the case of being close to the surface. .

The light source wavelength used for heating is simply selected in this embodiment. This is because, among the layers constituting the semiconductor laser, the superlattice active layer 1 to be disordered
This is because the longest band gap energy wavelength of 3 was the longest. In the case of a semiconductor laser, such a structure is often seen. Therefore, the light source wavelength is set to be shorter than the band gap energy wavelength of the well layer of the superlattice active layer 13 and longer than the band gap energy wavelength of the other layers. As a result, the light from the light source is well absorbed by the superlattice active layer 13 to be disordered and generates heat, and is hardly absorbed by the other layers and does not generate heat.

In this embodiment, the fundamental oscillation light (1060 nm) of the YAG laser is used after being converted to a wavelength of 1300 nm by parametric oscillation or difference frequency oscillation.

Although this is a mask used for light shielding for partial heat treatment, a transparent plate partially formed with a mirror is used in this embodiment. Since the mirror must reflect the light from the light source, a metal film or a dielectric multilayer film is used as the mirror portion. The light of the light source for heating the superlattice active layer 13 of the semiconductor laser shown in FIG. 1 is infrared light, and gold is a suitable material for the material of the mirror. On the contrary, the transparent plate must be capable of transmitting the light from the light source. As a material for the transparent plate, for example, quartz is an appropriate material because it transmits infrared light. In this embodiment, a quartz plate having a gold reflection mirror pattern is used as a light-shielding mask.

A semiconductor material including the light source, the light-shielding mask, and the quantum well to be disordered is arranged as shown in FIG. The light beam 26 emitted from the light source 25 is collimated by the lens 24, and the collimated light beam 26 reaches the semiconductor material 21 including the quantum well through the light shielding mask 22 which partially reflects and shields the light. In FIG. 2, the light source 25 includes a laser light source and a wavelength conversion mechanism. The light-shielding mask 22 on which the reflective film 23 is placed is arranged in close contact with the semiconductor material 21 including the quantum well. However, since the temperature of the light-shielding mask 22 may rise depending on the degree of heating, in that case, the light-shielding mask 22 may be separated from the semiconductor material 21 including the quantum wells by a distance of tens to hundreds of μm. Good. In addition, in FIG. 2, a semiconductor material 21 including a quantum well is formed using a lens 24.
Although the light from the light source is guided to, the light may be guided by an optical fiber or a beam expander may be used instead. The pattern of the reflective film 23 in FIG. 2 is an example, and does not represent the pattern required in this embodiment.

The heating is controlled by adjusting the output of the YAG laser which is the light source and the irradiation time. When the beam diameter of the heating laser light source is small, the beam or the object to be irradiated (in this case, the semiconductor material 2 including the quantum well 2 as shown by the arrow in FIG.
By scanning 1) vertically and horizontally, the entire surface of the irradiation target can be heated uniformly.

By the method described above, some quantum wells of the semiconductor laser material 21 are disordered. Specifically, the quantum well is disordered by irradiating the portion used as the merging waveguide with light, and the portion used as the semiconductor laser is shielded from light to prevent disorder.

When only the light guide layer 14 is laminated before heating, an InP clad layer 15 of a conductivity type different from the first conductivity type and a conductivity type different from the first conductivity type are formed on the light guide layer 14. InGaAs cap layer 16 is laminated.

Next, a merging waveguide is formed in the disordered portion. Here, after the etching mask is patterned in the shape of a rake of the merging waveguide, etching is performed and the surroundings are buried by burying growth. FIG. 3 shows a merging waveguide integrated semiconductor laser array in which even the merging waveguide is finally manufactured. In FIG. 3, 37 is a quantum well (active layer 3
6 is a non-disordered region, and 38 is a quantum well disordered region. In FIG. 3, semiconductor lasers 31, 32, 33, 34 are formed in an array in a non-disordered region 37, and the output light of these semiconductor lasers is 1
The merging waveguide 35 is formed so as to be integrated. In FIG. 3, the waveguide 35 and the like are processed as a buried type, but may be a ridge type. Waveguide part 3 for merging
The quantum well of No. 5 was the same as the light emitting units 31 to 34 before the disordering, but after the disordering, the bandgap energy wavelength becomes shorter and the light of the light emitting unit is not absorbed.
Therefore, the merging waveguide 35 with low absorption loss is obtained,
The light from the light emitting units 31 to 34 can be routed over a long distance, or the light from the light emitting units 31 to 34 can be combined to extract a large light output.

Moreover, in the semiconductor laser array with the waveguide for merging manufactured by the method of this embodiment, the light emitting portion is not heated, and the heating of the merging portion is performed only by the active layer 36. It took only a short time, and the temperature rise due to the heat conduction of the light-emitting part that was not desired to be heated was slightly suppressed, so no change due to the deterioration of the crystal or the disordering of the light-emitting part due to heating was not observed.

Second Embodiment This embodiment is characterized in that stress strain due to lattice constant mismatch is introduced into the quantum well active layer of a semiconductor laser. A part of this quantum well active layer is disordered to relieve stress strain and to have a desired function.

FIG. 4 shows the layer structure of the semiconductor laser manufactured according to this embodiment. The superlattice active layer of this semiconductor laser is the tensile strained quantum well active layer 43 having tensile strain stress in the quantum well. In a semiconductor laser having an ordinary strain-free quantum well active layer, the gain of TE polarization mode is T
Exceeds the gain of M polarization mode. However, in the semiconductor laser having the tensile strained quantum well active layer, the gain of the TM polarization mode is T if the tensile strain is set to a certain level or more.
The semiconductor laser exceeds the gain of the E polarization mode and always oscillates in the TM polarization mode.

This tensile strained quantum well active layer 43 is subjected to partial heat treatment by the method of the present invention to cause atomic diffusion at the hetero interface of the quantum well. Thus, the stress strain caused by the mismatch of the lattice constants at the interface is relaxed, the gain of the TE polarization mode exceeds the gain of the TM polarization mode, and the oscillation in the TE polarization mode is facilitated.

As shown in FIG. 4, for example, this semiconductor laser has an InP substrate 41 of the first conductivity type and an InP substrate 41.
An optical waveguide layer or optical guide layer 42 having a composition of GaAsP (bandgap wavelength 1.15 μm) is laminated to a thickness of 0.1 μm, and a strained quantum well activity having a tensile strain stress of about −1% on the well side is laminated thereon. Layer 43 is laminated. As the well layers of the strained quantum well active layer 43, In _x Ga _1-x As is 6 nm each.
Five layers with a thickness of InGaAsP (bandgap wavelength 1.15 μm) were sandwiched between the well layers with a thickness of 10 nm as a barrier layer. On top of this, an InGaAsP (bandgap wavelength 1.15 μm) optical waveguide layer or optical guide layer 44 is formed.
Heat treatment is performed only on a predetermined region in a state of being laminated in a thickness of μm.

The heat treatment is substantially the same as that of the first embodiment. The light source light wavelength used for heating is also substantially the same as in the first embodiment. This is because the band gap energy wavelength of the well layer of the tensile strained quantum well active layer 43 to be heat-treated is the longest among the layers constituting the semiconductor laser. The mask used for shading is also substantially the same as in the first embodiment.

A semiconductor laser material including the light source, the light-shielding mask, and the strained superlattice active layer 43 to be disordered is arranged as shown in FIG. This is also substantially the same as the description given in the first embodiment.

By the method described above, only the tensile strained quantum well active layer 43 of the semiconductor laser of this example was partially heat-treated to cause atomic diffusion at the hetero interface of the quantum well. In the region where atomic diffusion has occurred, the composition gently changes at the hetero interface, so the lattice constant also changes gently, the tensile strain stress is relaxed, and the state is almost strainless. When the layers up to the light guide layer 44 are stacked before heating, In having a conductivity type different from the first conductivity type is formed on the light guide layer 44.
The P clad layer 45 and the InGaAs cap layer 46 are laminated, and electrodes are independently formed on the tensile strained portion and the non-strained portion of the semiconductor laser to obtain a semiconductor laser. The polarization mode of the oscillation light of the semiconductor laser can be changed by changing the current ratio of the currents flowing through these electrodes. For example, when a large amount of current is applied to the tensile strain side electrode, TM mode oscillation occurs. On the contrary, when the current of the electrode on the tensile strain side is suppressed and the current of the electrode on the non-strain side is increased, the TE mode gain becomes dominant and the TE mode oscillation occurs. Thus, a semiconductor laser capable of arbitrarily switching the polarization mode by the electric current was obtained.

The polarization mode switch semiconductor laser described in this embodiment can be manufactured by a similar method using a conventional capping material such as silicon oxide and partial diffusion using an electric furnace.
However, the entire device is heated for a long time, and not only the portion capped with silicon oxide for which disordering is desired but also the disordering proceeds in other portions. Therefore, strain stress is relaxed up to an undesired portion of the tensile strained quantum well active layer, which makes it difficult for laser oscillation in the TM mode to occur.

On the other hand, in the semiconductor laser manufactured by the method of this embodiment, the temperature rise of the tensile strain quantum well active layer 43 which is not desired to be heated was slightly suppressed, so that the amount of tensile strain was increased due to the progress of diffusion due to heating. A good polarization switch can be observed without any change in the value.

Third Embodiment This embodiment relates to a method of manufacturing an electroabsorption type optical modulator integrated light source. This embodiment is an example in which a superlattice active layer of a semiconductor laser is partially disordered and processed as an electro-absorption optical modulator to manufacture an optical modulator integrated semiconductor laser.

FIG. 5 shows the final layer structure of the semiconductor laser of this embodiment. For example, in this semiconductor laser, an optical waveguide layer or optical guide layer 52 having a composition of InGaAsP (bandgap wavelength 1.15 μm) is laminated on an InP substrate 51 having the first conductivity type to a thickness of 0.1 μm, and the optical waveguide layer or optical guide layer 52 is laminated thereon. A multi-quantum well active layer 53 is laminated on the. As the well layers of the multiple quantum well active layer 53, In _0.53 Ga _0.47 As is 6 nm each.
Five layers with a thickness of InGaAsP (bandgap wavelength 1.15 μm) were sandwiched between the well layers with a thickness of 10 nm as a barrier layer. An InGaAsP (bandgap wavelength 1.15 μm) optical waveguide layer or optical guide layer 54 is formed on top of it by 0.1
Heat treatment is partially performed in a state of being laminated to a thickness of μm.

Also in this embodiment, the first heat treatment is the first.
It is substantially the same as the method of the embodiment. The light source light wavelength used for heating is also substantially the same as in the first embodiment.
This is because the band gap energy wavelength of the well layer of the multiple quantum well active layer 53 to be heat-treated is the longest among the layers constituting the semiconductor laser. The mask used for shading is also substantially the same as in the first embodiment.

A semiconductor laser material including the light source, the light-shielding mask, and the strained superlattice active layer 43 to be disordered is arranged as shown in FIG. This is also substantially the same as the description given in the first embodiment.

By the method described above, the partial superlattice active layer of the semiconductor laser material is disordered. The degree of disorder is small, and heating is performed so that the diffusion of atoms slightly occurs at the hetero interface between the quantum well layer and the barrier layer of the active layer 53 and the well width is reduced. When the layers up to the optical guide layer 54 are stacked before heating, an InP clad layer 55 and an InGaAs cap layer 56 having a conductivity type different from the first conductivity type are formed on the light guide layer 54.
Are laminated. After that, an electrode is provided separately for the disordered portion and the non-disordered portion to electrically separate them, and they are used as an optical modulator (disordered portion) and a semiconductor laser (non-disordered portion), respectively. Create a laser. The active layer 53 of the electro-absorption optical modulator portion was the same as the light emitting portion before the disordering, but after the disordering, the bandgap energy wavelength became shorter, so that the absorption of the semiconductor laser oscillation light decreased, The output of the semiconductor laser that is modulated and taken out increases. When a reverse voltage is applied to the optical modulator portion, the bandgap energy wavelength of the disordered active layer 53 becomes slightly longer and absorption of semiconductor laser oscillation light occurs.

In the optical modulator integrated type semiconductor laser manufactured by the method of this embodiment, the light emitting portion is not heated, and the optical modulator portion is heated only by the active layer. For this reason, the heat treatment was completed in a short time, the temperature of the light emitting portion, which is not desired to be heated due to heat conduction, was hardly increased, and the characteristics of the light emitting portion were not deteriorated due to crystal deterioration or disorder due to heating.

[0056]

As described above, the first embodiment according to the present application is described.
According to the invention of (1), it is possible to disorder only the superlattice active layer or the like at a desired position by light irradiation, light shielding by a mask (light shielding plate), and selection of an appropriate light source wavelength.

According to the second invention of the present application,
By irradiating light, blocking light by a mask, and selecting an appropriate light source wavelength, it is possible to disorder only the strained quantum well active layer at a desired position to relax the strain.

According to the third invention of the present application,
The light shielding plate does not have much heat, and the semiconductor laminated material and the light shielding plate can be arranged in close contact with each other.

Further, according to the fourth, fifth and sixth inventions of the present application, since only the desired portion can be accurately heated, a semiconductor laser array with a merging waveguide and an optical modulator integrated semiconductor laser having good characteristics. A semiconductor laser capable of switching the oscillation polarization mode can be manufactured with good reproducibility.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating the structure of a semiconductor laser layer manufactured in a first example.

FIG. 2 is a light source / mask / performing the manufacturing method of the present invention.
It is a perspective view explaining board arrangement.

FIG. 3 is a perspective view illustrating a final form produced in the first embodiment.

FIG. 4 is a cross-sectional view illustrating a semiconductor laser layer structure manufactured in a second example.

FIG. 5 is a cross-sectional view illustrating the structure of a semiconductor laser layer manufactured in the third example.

FIG. 6 is a diagram showing a band structure of a quantum well (before and after disordering).

[Explanation of symbols]

 11, 41, 51: Substrate 12, 14, 42, 44, 52, 54: Optical guide layer 13, 36, 53: Quantum well active layer 15, 45, 55: Clad layer 16, 46, 56: Cap layer 21: Semiconductor material 22: Mask 23: Reflecting film 24: Lens 25: Light source 26: Light flux 31, 32, 33, 34: Semiconductor laser 35: Converging waveguide 37: Non-disordered region 38: Disordered region 43: Strain quantum Well active layer 101: conduction band before disordering 102: valence band before disordering 103: conduction band after disordering 104: valence band after disordering

Claims (6)

[Claims] 1. A semiconductor device comprising a step of irradiating a semiconductor laminated material having a semiconductor superlattice structure with a light source to heat the semiconductor superlattice structure by absorbing light from the light source to disorder the semiconductor superlattice structure. In the manufacturing method, the light source wavelength is shorter than the longest bandgap energy wavelength of the semiconductor superlattice structure and longer than the bandgap energy wavelengths of other semiconductor layers stacked on the semiconductor superlattice structure, and the light source and the semiconductor A light-shielding plate that partially shields the light source light is placed between the laminated materials, and the position of the light-shielding plate is adjusted, whereby the light source light irradiation position on the semiconductor laminated material can be adjusted. Method of manufacturing a semiconductor element. 2. The semiconductor superlattice structure includes stress strain caused by mismatch of lattice constants between semiconductor thin film layers constituting the semiconductor superlattice structure before heating, thereby disordering the semiconductor superlattice structure. 2. The method for producing a semiconductor device according to claim 1, wherein a steep mismatch of lattice constants at the interface of the semiconductor thin film layer is eliminated to alleviate stress strain. 3. The method for manufacturing a semiconductor element according to claim 1, wherein the light shielding plate is a reflecting plate in which a carrier that transmits the light source light is provided with a mirror surface portion that reflects the light source light. 4. A method for manufacturing a semiconductor laser array with a merging waveguide, wherein the plurality of semiconductor laser portions are not heated by adjusting the position of the light-shielding plate and are connected to the emission end of each semiconductor laser. 4. The method for manufacturing a semiconductor device according to claim 1, wherein only the heating of the semiconductor superlattice active layer in the merging waveguide portion is performed. 5. A method for manufacturing an optical modulator integrated semiconductor laser, wherein the semiconductor laser portion is not heated by adjusting the position of the light shielding plate, and the optical modulator is connected to the emitting end of the semiconductor laser. 4. The method for producing a semiconductor device according to claim 1, wherein only a part of the semiconductor superlattice active layer is heated. 6. A method of manufacturing a semiconductor laser capable of switching an oscillation polarization mode, wherein the tensile strained quantum well active layer is partially heated by adjusting the position of the light shielding plate. Item 4. A method for manufacturing a semiconductor device according to any one of Items 1 to 3.