JP2002335053A - Semiconductor laser, manufacturing method thereof, semiconductor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily manufacture a semiconductor laser using a nitride III-V compound semiconductor whose operation current increases extremely little during energization, life is long and deterioration is extremely little over aging. SOLUTION: After an edge faced of a resonator of a semiconductor laser is formed wherein a nitride III-V compound semiconductor is used, a process for exposing a resonator edge to a plasma atmosphere of inert gas or heating it at a temperature of 30 deg.C or higher and 700 deg.C or lower in vacuum or inert gas atmosphere, and a process for exposing a resonator edge to a plasma atmosphere of inert gas, are carried out, or a resonator edge face is exposed to plasma atmosphere of inert gas at a temperature of 30 deg.C or higher and 700 deg.C or lower. After these treatments, edge face coating is performed for a resonator edge. Alternately, edge coating is performed for a resonator edge via an adhesion layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor laser, a semiconductor laser, a method for manufacturing a semiconductor device, and a semiconductor device, and more particularly, to a semiconductor laser, a light emitting diode, or a semiconductor laser using a nitride III-V compound semiconductor. It is suitable for application to the manufacture of an electron transit element.

[0002]

2. Description of the Related Art In recent years, as a semiconductor laser capable of emitting light from a blue region to an ultraviolet region, which is necessary for increasing the density of an optical disk, a nitride III-based laser such as AlGaInN has been used.
Research and development of semiconductor lasers using group V compound semiconductors have been actively conducted, and recently efforts have been made to further improve the life and characteristics for practical use.

[0003]

However, at present, an increase in operating current during energization is observed in a semiconductor laser using a nitride III-V compound semiconductor. This increase in operating current during energization is one of the important factors that determine the life of the semiconductor laser, and its suppression is desired.

Accordingly, an object of the present invention is to provide a semiconductor laser using a nitride-based III-V compound semiconductor, which has a very small increase in operating current during energization, a long life and an extremely small change with time. An object of the present invention is to provide a method of manufacturing a semiconductor laser which can be easily manufactured.

Another problem to be solved by the present invention is that
An object of the present invention is to provide a semiconductor laser using a nitride-based III-V compound semiconductor, which has a very small increase in operating current during energization, has a long life, and has very little change over time, and a method for manufacturing the same.

[0006] More generally, the problem to be solved by the present invention is that the increase in operating current during energization is extremely small.
It is an object of the present invention to provide a semiconductor laser using a group III-V compound semiconductor or another semiconductor which has a long life and extremely little change with time, and a method for manufacturing the same.

More generally, an object to be solved by the present invention is to improve an end face formed by processing a nitride III-V compound semiconductor, and to provide an end face on this end face. An object of the present invention is to provide a method of manufacturing a semiconductor device capable of improving the adhesion when coating is performed.

Another problem to be solved by the present invention is that
An end face formed by processing a nitride-based III-V compound semiconductor can be improved, and
It is an object of the present invention to provide a semiconductor device and a method for manufacturing the same, which can improve the adhesion when the end face is coated with the end face.

[0009] Another problem to be solved by the present invention is as follows.
A semiconductor device capable of improving an end face formed by processing a III-V compound semiconductor or another semiconductor, and improving the adhesion when the end face is coated with the end face; It is to provide a manufacturing method thereof.

[0010]

Means for Solving the Problems The present inventor has made intensive studies to solve the above-mentioned problems. The outline is as follows. That is, the present inventor:
As a result of various experiments and investigations, it was found that the nitride III-
An increase in operating current during energization in a semiconductor laser using a group V compound semiconductor destroys the vicinity of the end face of the resonator.
It has been found that so-called end face deterioration is the biggest factor. Here, in a semiconductor laser using a nitride-based III-V compound semiconductor, end face degradation or optical damage (COD; catastrophic optical damage)
The fact is that it has hardly been reported so far.

[0011] In order to prevent the end face deterioration from being suppressed, in a semiconductor laser of another material system, an end face coating is applied in order to prevent the crystal near the end face of the resonator from being oxidized. For example, in an AlGaAs semiconductor laser, SiO ₂ , Si ₃ N ₄ ,
Al ₂ O ₃ etc. (for example, J. Appl. Phy
s. 50 (1979) p. 5150, Appl. Phys. Lett. 30 (1977) p. 87).

However, according to the findings of the present inventors, in a semiconductor laser using a nitride III-V compound semiconductor, an end face coating material is formed to stabilize the end face of the resonator, and the end face of the resonator is formed. When a life test was performed on a device protected by the above, a sudden increase in operating current was confirmed in almost all devices, contrary to expectations. As a result of studying the cause, the present inventor has found that deterioration near the resonator end face is the dominant factor. In other words, in a semiconductor laser using a nitride-based III-V compound semiconductor, simply applying an end face coating that is considered to be effective for suppressing the end face deterioration in an AlGaAs semiconductor laser or the like prevents the end face deterioration. It came to the conclusion that it was difficult.

The inventor of the present invention has conducted various studies on a fundamental solution to the problem of a sudden increase in operating current. As a result, after forming the resonator end face, the end face of the resonator was exposed to an inert gas plasma atmosphere. It has been found that it is effective to perform heat treatment or to combine it with heat treatment, and further, various studies have been made on such conditions.

Thereafter, as a result of further investigation, it was confirmed that one of the factors of the end face deterioration was that the adhesion of the end face coat film itself to the end face of the resonator was not good. Therefore, the present inventor considered forming an end face coat film via an adhesion layer in order to improve the adhesion of the end face coat film to the cavity end face. As a result of searching for an optimum material for the adhesion layer, a material containing a metal such as Al or a metal such as Al and oxygen and the like that is sufficiently thin enough not to adversely affect the laser characteristics is preferable. I found something. Of these, metal such as Al is used for the resonator end face,
In particular, the formation in the region including the light-emitting portion was not considered with conventional common sense because of adverse effects on the laser characteristics. It was found that the adhesion of the coat film could be improved.

Although the above description is for a semiconductor laser, the above-described method improves the end face in a semiconductor device in which an end face is formed by processing a nitride III-V compound semiconductor by cleavage or dry etching. It is also effective in stabilizing the end face and in improving the adhesion when the end face is coated. Also, the method of forming an end face coat film on the cavity end face via an adhesion layer is effective for a semiconductor laser using a III-V compound semiconductor other than a nitride III-V compound semiconductor and other semiconductors. And a III-V compound semiconductor other than a nitride III-V compound semiconductor.
In a semiconductor device in which an end face is formed by processing a group V compound semiconductor or another semiconductor by cleavage, dry etching, or the like, it is also effective in improving the adhesion when the end face is coated with the end face. is there. The present invention was devised as a result of further studies based on the above studies by the present inventors.

That is, in order to solve the above problems, a first aspect of the present invention is to provide a method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, wherein a cavity facet of the semiconductor laser is formed. Thereafter, the end face of the resonator is exposed to a plasma atmosphere of an inert gas.

The second invention of the present invention relates to a nitride III
In the method for manufacturing a semiconductor laser using a group V compound semiconductor, after forming the cavity facet of the semiconductor laser, the semiconductor laser is heated to 30 ° C. or more in a vacuum or in an inert gas atmosphere.
The method is characterized by comprising a step of heating at a temperature of not more than ° C. and a step of forming a cavity facet of the semiconductor laser and exposing the cavity facet to a plasma atmosphere of an inert gas. Here, any of these steps may be performed first, but from the viewpoint of more completely performing surface treatment such as cleaning of the resonator end face, the heating step is preferably performed first. Further, in some cases, a heating step may be performed before and after the step of exposing to an inert gas plasma atmosphere.

The third invention of the present invention relates to a nitride III
In a method of manufacturing a semiconductor laser using a Group V compound semiconductor, after forming a cavity facet of the semiconductor laser, the cavity facet is exposed to a plasma atmosphere of an inert gas at a temperature of 30 ° C. or more and 700 ° C. or less. It is characterized by having made it.

The fourth invention of the present invention relates to a nitride III
In a method of manufacturing a semiconductor laser using a group V compound semiconductor, after forming a resonator end face by processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape, The end face of the resonator is exposed to a plasma atmosphere of an inert gas.

The fifth invention of the present invention is directed to a nitride III
In a method of manufacturing a semiconductor laser using a group V compound semiconductor, after forming a resonator end face by processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape, Heating at a temperature of 30 ° C. or more and 700 ° C. or less in a vacuum or an inert gas atmosphere, and processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape. Exposing the cavity end face to a plasma atmosphere of an inert gas after forming the cavity end face by using the above method. Here, any of these steps may be performed first, but from the viewpoint of more completely performing surface treatment such as cleaning of the resonator end face, the heating step is preferably performed first. Further, in some cases, a heating step may be performed before and after the step of exposing to an inert gas plasma atmosphere.

The sixth invention of the present invention relates to a nitride-based III
In a method of manufacturing a semiconductor laser using a group V compound semiconductor, after forming a resonator end face by processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape, Keep the end face of this resonator at 30 ° C.
It is characterized in that it is exposed to an inert gas plasma atmosphere at a temperature of 00 ° C. or less.

A seventh aspect of the present invention is directed to a nitride type III
A method for manufacturing a semiconductor device having an end face formed by processing a group V compound semiconductor, wherein the end face is formed and then exposed to an inert gas plasma atmosphere after forming the end face. It is.

An eighth invention of the present invention is directed to a nitride-based III
In the method for manufacturing a semiconductor device having an end face formed by processing a group V compound semiconductor, after forming the end face, the semiconductor device may be formed in a vacuum or in an inert gas atmosphere.
The method is characterized by comprising a step of heating at a temperature of not lower than 700 ° C. and a step of exposing the end face to a plasma atmosphere of an inert gas after forming the end face.
Here, any of these steps may be performed first,
From the viewpoint of more completely performing surface treatment such as cleaning of the end face, the heating step is preferably performed first. Further, in some cases, a heating step may be performed before and after the step of exposing to an inert gas plasma atmosphere.

The ninth invention of the present invention is directed to a nitride-based III
In the method for manufacturing a semiconductor device having an end face formed by processing a group V compound semiconductor, after forming the end face, the end face is exposed to a plasma atmosphere of an inert gas at a temperature of 30 ° C. or more and 700 ° C. or less. It is characterized by doing so.

According to a tenth aspect of the present invention, there is provided a nitride-based II
In a semiconductor laser using an IV group compound semiconductor,
An end face coat film is formed on the end face of the resonator via an adhesive layer.

According to an eleventh aspect of the present invention, there is provided a nitride-based II
A method of manufacturing a semiconductor laser using an IV group compound semiconductor, wherein a cavity facet of a semiconductor laser is formed, and then the cavity facet is coated with an end face via an adhesion layer. It is.

According to a twelfth aspect of the present invention, there is provided a nitride-based II
In a method of manufacturing a semiconductor laser using an IV group compound semiconductor, after forming a resonator end face by processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape An end face coating is applied to the end face of the resonator via an adhesive layer.

According to a thirteenth aspect of the present invention, there is provided a nitride-based II
In a semiconductor device having an end face formed by processing an IV group compound semiconductor, an end face coat film is formed on the end face via an adhesion layer.

The fourteenth invention of the present invention relates to a nitride-based II
In a method for manufacturing a semiconductor device having an end face formed by processing an IV compound semiconductor, after forming the end face, the end face is coated with an end face via an adhesion layer. Things.

In the first to fourteenth aspects of the present invention,
Ga, Al, I
At least one group III element selected from the group consisting of n and B, and a group V element containing at least N and optionally further containing As or P. Specific examples of the nitride III-V compound semiconductor include Ga
N, AlGaN, AlN, GaInN, AlGaIn
N, InN and the like.

In the first to ninth aspects of the present invention,
Typically, after exposing an inert gas to a plasma atmosphere or the like, an end face coating is applied to the end face of the resonator or the end face of the semiconductor device without exposing the end face of the resonator or the end face of the semiconductor device to the atmosphere. Specifically, for example, using an apparatus capable of performing plasma processing and film formation, continuously exposing an inert gas to a plasma atmosphere and coating an end face in the processing chamber, or using an inert gas in a plasma processing apparatus. After the exposure to the plasma atmosphere, the object to be processed is transferred to a film forming apparatus through a transfer path in a vacuum or inert gas atmosphere, and the end face is coated.

As the inert gas for generating the plasma or the inert gas used for the atmospheric gas during heating, any of a rare gas, a nitrogen gas or a mixed gas thereof may be used, and almost the same effect can be obtained. it can. As the rare gas, an argon gas or a xenon gas is preferably used from the viewpoint of efficiently performing surface treatment such as flattening or cleaning of the cavity end face or the end face.

The energy of the plasma, that is, the plasma output × the processing time, is preferably 0.5 kilowatt seconds (for example, from the viewpoint of obtaining a necessary or minimum surface treatment effect such as flattening or cleaning of the end face of the resonator or the end face thereof. 50 watts x 1
0 seconds) or more, and preferably 900 kilowatt seconds (for example, 500 watts x 1800 seconds) or less, more preferably 100 kilowatt seconds or more and 500 kilowatt seconds or less from the viewpoint of suppressing damage to the cavity end face or the end face by plasma. And In this case, the output of the plasma is preferably 50 watts or more, more preferably 100 watts or more, from the viewpoint of sufficiently obtaining surface treatment effects such as flattening and cleaning of the cavity end face or the end face. From the viewpoint of suppressing damage to the cavity end face or the end face due to the above, preferably 1000 watts or less, more preferably 800 watts or less.
Watts or less, more preferably 500 watts or less.
In addition, the exposure time of the inert gas to the plasma atmosphere is preferably 10 seconds or more, more preferably 10 seconds or more, from the viewpoint of sufficiently and stably obtaining a surface treatment effect such as flattening or cleaning of the cavity end face or the end face. Is at least 1 minute, more preferably at least 5 minutes, even more preferably at least 10 minutes. The pressure of the processing chamber before forming the plasma atmosphere of the inert gas is preferably 1 × 1 from the viewpoint of stably forming the plasma atmosphere.
0 ^-4 Pa or less. Further, the pressure of the processing chamber after forming the plasma atmosphere of the inert gas maintains the plasma atmosphere stably, and obtains a sufficient and stable surface treatment effect such as flattening or cleaning of the cavity end face or the end face. From a perspective,
It is preferably at least 0.8 × 10 ^-2 Pa and not more than 1.2 × 10 ^-2 Pa, particularly about 1 × 10 ^-2 Pa. Further, from the viewpoint of suppressing damage to the resonator end face or the end face due to plasma, the voltage is preferably not applied to the holding section, and the object to be processed for processing the resonator end face or the end face is in a self-biased state. To hold.

The heating temperature before and / or after the exposure of the inert gas to the plasma atmosphere or at the time of the exposure to the inert gas to the plasma atmosphere is sufficient for effecting the surface treatment such as the end face of the resonator or the cleaning of the end face. From the viewpoint of securing the cavity surface or stabilizing the cavity end face or the end face after the treatment, preferably at least 50 ° C., more preferably at 100 ° C.
In addition, the temperature is preferably set to 700 ° C. or less from the viewpoint of preventing deterioration of a growth layer of a nitride III-V compound semiconductor, particularly an active layer, and the like, and from the viewpoint of preventing deterioration of an electrode, particularly a p-side electrode. Therefore, the temperature is preferably set to 400 ° C. or less. The heating temperature can be set to a temperature within the range of any combination of the lower limit and the upper limit as necessary.
When heating is performed in a vacuum, the pressure is preferably set to 1 × from the viewpoint of flattening or cleaning the end face of the resonator or the end face.
It is set to 10 ⁻⁴ Pa or less.

In the tenth to twelfth aspects of the present invention, the adhesion layer is preferably formed on a region including at least the light emitting portion on the cavity end surface, that is, a region where the adhesion of the end surface coating film is most required. Typically, it is formed on the entire end face of the resonator. The adhesion layer may be either a continuous film or a fine particle, or may be a continuous film and fine particles thereon.

When a continuous film is used as the adhesion layer, its thickness is appropriately selected in consideration of the material to be used, but when the material to be used is a metal in particular, if it is too thick, light absorption increases. From the viewpoint of suppressing light absorption, it is preferably selected to be 10 nm or less, more preferably 5 nm or less, and still more preferably 2 nm or less. The lower limit of the thickness of the adhesion layer is a thickness corresponding to one atomic layer or one molecular layer. In the case where the material to be used is conductive, the continuous film is preferably formed of an n-type semiconductor laser to form a semiconductor laser structure in order to reliably prevent short-circuiting of the pn junction on the cavity end face. It is formed so as not to straddle the layer and the p-type layer.

On the other hand, in the case where a material composed of fine particles is used as the adhesion layer, if the fine particles are too large, the energy reflectivity of the cavity end face on which the fine particles are formed becomes too large, and the operating current of the semiconductor laser increases. Invite
Since it is not preferable, the size of the fine particles needs to be set so that the energy reflectance of the end face of the resonator becomes equal to or less than a predetermined value. Specifically, the energy reflectivity when the cavity facet is flat is R ₀ , and the energy reflectivity when the adhesion layer made of fine particles is formed on the cavity facet is R ₀ .
_{If s} , oscillation wavelength is λ, refractive index of the fine particles is n, and average height of the fine particles is σ, then R _s = R ₀ exp [− (4πn (σ / λ)) ² ] (Yoshida (Sadafumi, Hiroyoshi Yajima, “Thin Film / Optical Device”, University of Tokyo Press), σ is set so that R _s obtained from this equation is equal to or less than a predetermined value. As a specific example, assuming a front end face of the resonator, R ₀ =
0.10, λ = 400 nm, n (Al) = 3.90 for λ = 400 nm when the fine particles are made of Al, or n (AlN) = for λ = 400 nm when the fine particles are made of AlN When the change in R _s due to σ / λ is obtained by calculation using 2.224 as shown in FIG. 1, the result is as shown in FIG. Also, the change amount of R _s due to σ / λ = (R _s
When calculating (−0.1) × 100 (%), the result is as shown in FIG. Now, considering the case where R _s ≦ 0.6, for this purpose, when the fine particles are made of Al, σ / λ ≦ 0.028 When the fine particles are made of AlN, σ / λ ≦ 0.048 must be satisfied. No. Since λ = 400 nm,
In this case, when the fine particles are made of Al, σ ≦ 11.2 nm When the fine particles are made of AlN, σ ≦ 19.2 nm. Assuming that the surface tension acts on the fine particles formed on the cavity end face and the height and the width are the same, when the fine particles are made of Al, the width is 11.2 nm or less, and the fine particles are made of AlN. In that case, the width is 19.2 nm or less.

The material of the adhesion layer is selected as necessary,
Typically, at least one element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn and Si, or Al, Ti, Zr, Hf, T
a substance containing at least one element selected from the group consisting of a, Zn and Si, and oxygen and / or nitrogen. In addition, various film formation methods such as a sputtering method and a vacuum evaporation method (for example, an electron beam evaporation method) can be used for forming the adhesion layer.

The end face coat film is typically composed of a single-layer or multi-layer dielectric film (dielectric multilayer film). in this case,
Typically, the adhesion layer and the dielectric film in contact with the adhesion layer include at least one element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn, and Si;
Alternatively, it contains at least one and the same element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn and Si. Specifically, for example, the dielectric film in contact with the adhesion layer is made of Al ₂ O ₃ , and the adhesion layer is a substance made of Al and O, for example, a substance having an intermediate composition between Al and Al ₂ O ₃ , that is, AlO _x (where 0 <x <1.5). This adhesion layer may be a substance mainly containing at least Al and O, for example, a substance mainly containing AlO _x . Alternatively, the dielectric film in contact with the adhesion layer is made of AlN, and the adhesion layer is made of a material composed of Al and N, for example, a material having an intermediate composition between Al and AlN, that is, AlN.
_x (where, 0 <x <1) there also be a.

In the thirteenth and fourteenth aspects of the present invention, as for the adhesion layer and the end face coating film, basically the same as those described in relation to the tenth to twelfth aspects of the present invention hold, but a semiconductor laser There are no constraints specific to.

In the tenth to fourteenth aspects of the present invention, preferably, after forming the resonator end face or the end face,
After or while exposing the resonator end face or the end face to the plasma atmosphere of the inert gas, an adhesion layer is formed on the resonator end face or the end face. The conditions for the plasma treatment of the inert gas at this time are basically the same as described above. After the adhesion layer is formed, the end face of the resonator or the end face is preferably coated with an end face without exposing the end face of the resonator or the end face to the atmosphere.

Various substrates can be used as a substrate on which the nitride-based III-V compound semiconductor layer is grown. Specifically, a sapphire substrate, a SiC substrate, a Si substrate, a GaAs substrate, a GaP substrate, an InP In addition to a substrate, a spinel substrate, a silicon oxide substrate, and the like, a substrate made of a nitride III-V compound semiconductor layer such as a thick GaN layer may be used.

As a method of growing a nitride III-V compound semiconductor, for example, metal organic chemical vapor deposition (MOC)
VD), hydride vapor phase epitaxial growth or halide vapor phase epitaxial growth (HVPE).

The semiconductor device is formed by processing a nitride III-V compound semiconductor by cleavage or dry etching or the like to form an end face of an element portion (an end face of a semiconductor chip or formed on a nitride III-V compound semiconductor layer by etching). Basically, any material may be used as long as it forms an end face of a mesa portion to be formed.
An electron transit element such as an ET or a heterojunction bipolar transistor.

The first to fourteenth aspects of the present invention relate to
The present invention relates to a semiconductor laser or a semiconductor device using a II-V compound semiconductor.
A method similar to that of the fourteenth invention is basically based on nitride-based
Various III-V semiconductors other than II-V compound semiconductors, including AlGaAs-based semiconductors, AlGaInP-based semiconductors, etc.
The present invention can be applied to a semiconductor laser or a semiconductor device using a group III compound semiconductor.
The present invention can be applied to a semiconductor laser or a semiconductor device using various semiconductors including a group II-VI compound semiconductor in addition to a group III compound semiconductor.

That is, the fifteenth invention of the present invention relates to
A semiconductor laser using a II-V group compound semiconductor is characterized in that an end face coat film is formed on an end face of a resonator via an adhesion layer.

According to a sixteenth aspect of the present invention, in a method of manufacturing a semiconductor laser using a group III-V compound semiconductor, after forming a cavity facet of a semiconductor laser, the cavity facet is formed on the cavity facet via an adhesion layer. It is characterized in that a coating is applied.

According to a seventeenth aspect of the present invention, in a method of manufacturing a semiconductor laser using a group III-V compound semiconductor, a substrate on which a semiconductor laser structure using a group III-V compound semiconductor is formed is processed into a bar shape. Then, after forming the resonator end face, the end face coating is applied to the resonator end face via an adhesion layer.

According to an eighteenth aspect of the present invention, in a semiconductor device having an end face formed by processing a III-V compound semiconductor, an end face coat film is formed on the end face via an adhesion layer. It is a feature.

According to a nineteenth aspect of the present invention, in a method of manufacturing a semiconductor device having an end face formed by processing a III-V compound semiconductor, an end face is formed, and the end face is then interposed through an adhesive layer. An end face coating is applied.

According to a twentieth aspect of the present invention, there is provided a semiconductor laser, wherein an end face coating film is formed on an end face of the resonator via an adhesion layer.

According to a twenty-first aspect of the present invention, there is provided a method for manufacturing a semiconductor laser, comprising forming an end face of a resonator and then coating the end face of the resonator via an adhesive layer.

According to a twenty-second aspect of the present invention, a substrate on which a semiconductor laser structure is formed is processed into a bar shape to form a cavity end surface, and then the cavity end surface is coated with an end surface via an adhesion layer. A method for manufacturing a semiconductor laser, characterized in that:

According to a twenty-third aspect of the present invention, in a semiconductor device having an end face formed by processing a semiconductor, an end face coat film is formed on the end face via an adhesion layer. is there.

According to a twenty-fourth aspect of the present invention, there is provided a method for manufacturing a semiconductor device having an end face formed by processing a semiconductor, wherein the end face is formed, and the end face is coated with an end face via an adhesion layer. It is characterized by having made it.

In the fifteenth to twenty-fourth aspects of the present invention, what has been described with respect to the tenth to twelfth aspects of the present invention basically holds for the adhesion layer and the end face coating film.

[0057] The first to fifth embodiments of the present invention configured as described above.
According to the ninth aspect, after forming the cavity facet of the semiconductor laser or the facet of the semiconductor device, the cavity facet or the facet is exposed to a plasma atmosphere of an inert gas, or a vacuum or an inert gas atmosphere. 30 ° C in
Heating at a temperature of not less than 700 ° C. and exposing the cavity end face or end face to an inert gas plasma atmosphere, or plasma atmosphere of a resonator end face or end face inert gas at a temperature of 30 ° C. to 700 ° C. By exposing to the cavity, it is possible to remove fine irregularities, oxides, contaminants, and the like existing on the end face of the resonator or the end face, and to planarize or clean the end face. And
The end face of the resonator or the affinity of the coating material with respect to the end face can be improved, and thus the adhesion can be improved. In particular, in a semiconductor laser, since the cavity facet is cleaned, the interface state of the cavity facet can be significantly reduced, and the non-radiative recombination at the cavity facet is greatly reduced. In addition to this, the contamination of the coat film with the impurities can be suppressed, and the light deterioration due to the contamination can be suppressed.

According to the tenth to twenty-fourth aspects of the present invention, after forming the end face of the resonator of the semiconductor laser or the end face of the semiconductor device, the end face coating film is formed on the end face of the resonator or the end face via the adhesion layer. Is formed, the adhesion of the end face coat film can be greatly improved.

[0059]

Embodiments of the present invention will be described below with reference to the drawings. For convenience of explanation, first, the structure of a GaN-based semiconductor laser manufactured according to the following embodiment will be described.

FIGS. 3 and 4 show this GaN-based semiconductor laser. Here, FIG. 3 is a sectional view perpendicular to the resonator length direction, and FIG. 4 is a sectional view parallel to the resonator length direction. This G
The aN-based semiconductor laser has a ridge structure and SCH (Sepa).
Rate Confinement Heterostructure).

As shown in FIG. 3 and FIG.
In a semiconductor laser, an undoped Ga grown on a c-plane sapphire substrate 1 through a low-temperature undoped GaN buffer layer 2 using a lateral crystal growth technique such as ELO (Epitaxial Lateral Overgrowth).
N layer 3, n-type GaN contact layer 4, n-type AlGaN cladding layer 5, n-type GaN optical waveguide layer 6, for example, the activity of an undoped In _x Ga _1-x N / In _y Ga _1-y N multiple quantum well structure Layer 7, n-type undoped InGaN deterioration preventing layer 8, p-type AlGaN cap layer 9, p-type GaN optical waveguide layer 10, p-type AlGaN cladding layer 11, and p-type GaN
The contact layers 12 are sequentially stacked.

Here, the undoped GaN buffer layer 2 has a thickness of, for example, 30 nm. The undoped GaN layer 3 has a thickness of, for example, 0.5 μm. The n-type GaN contact layer 4 has a thickness of, for example, 4 μm, and is doped with, for example, silicon (Si) as an n-type impurity. n-type AlG
The aN cladding layer 5 has a thickness of, for example, 1.0 μm, and n
For example, Si is doped as the type impurity, and the Al composition is, for example, 0.07. The n-type GaN optical waveguide layer 6 has a thickness of, for example, 0.1 μm, and is doped with, for example, Si as an n-type impurity. Also, undoped In _x Ga _1-x N
For example, the active layer 7 of the / In _y Ga _{1- y} N multiple quantum well structure has an In _x Ga _1-x N layer as a well layer having a thickness of 3.
X = 0.08 at 5 nm, In _y Ga _1-y as barrier layer
The thickness of the N layer is 7 nm, y = 0.02, and the number of wells is 3.

The undoped InGaN deterioration preventing layer 8 has a graded structure in which the In composition gradually decreases monotonously from the surface in contact with the active layer 7 toward the surface in contact with the p-type AlGaN cap layer 9. The In composition on the surface in contact with the active layer 7 is In _y as a barrier layer of the active layer 7.
It is consistent with the In composition y of the Ga _1-y N layer, and the p-type AlG
The In composition on the surface in contact with the aN cap layer 9 is 0.
It has become. This undoped InGaN deterioration preventing layer 8
Is, for example, 20 nm.

The p-type AlGaN cap layer 9 has a thickness of, for example, 10 nm and is doped with, for example, magnesium (Mg) as a p-type impurity. The Al composition of the p-type AlGaN cap layer 9 is, for example, 0.2. The p-type AlGaN cap layer 9 includes a p-type GaN optical waveguide layer 10,
In order to prevent In from being desorbed from the active layer 7 during the growth of the p-type AlGaN cladding layer 11 and the p-type GaN contact layer 12 and to prevent deterioration, and to prevent carriers (electrons) from overflowing from the active layer 9. It is. The thickness of the p-type GaN optical waveguide layer 10 is, for example, 0.1 μm.
And Mg is doped as a p-type impurity. The p-type AlGaN cladding layer 11 has a thickness of, for example, 0.1.
5 μm, for example, Mg is doped as a p-type impurity, and the Al composition is, for example, 0.07. The p-type GaN contact layer 12 has a thickness of, for example, 0.1 μm, and is doped with, for example, Mg as a p-type impurity.

Upper layer of n-type GaN contact layer 4, n-type AlGaN cladding layer 5, n-type GaN optical waveguide layer 6, active layer 7, undoped InGaN deterioration preventing layer 8, p-type AlG
The aN cap layer 9, the p-type GaN optical waveguide layer 10, and the p-type AlGaN cladding layer 11 have a mesa shape having a predetermined width. P-type AlGaN cladding layer 11 in this mesa portion
The ridge 13 extending in, for example, the <1-100> direction or the <11-20> direction is formed in the upper layer portion and the p-type GaN contact layer 13. The width of the ridge 13 is, for example, 1.6 μm.

An insulating film 14 such as a 0.3 μm thick SiO ₂ film is provided so as to cover the entire mesa portion. This insulating film 14 is for electrical insulation and surface protection. An opening 14 a is provided in a portion of the insulating film 14 above the ridge 13, and the p-side electrode 15 is in contact with the p-type GaN contact layer 13 through the opening 14 a. This p-side electrode 15 is composed of Pd
Film, a Pt film, and an Au film are sequentially laminated.
The thickness of each of the d film, the Pt film and the Au film is, for example, 10
nm, 100 nm and 300 nm. On the other hand, an opening 14 is formed in a predetermined portion of the insulating film 14 adjacent to the mesa portion.
b through the opening 14b.
The n-side electrode 16 is in contact with the N contact layer 4. The n-side electrode 16 has a structure in which a Ti film, a Pt film, and an Au film are sequentially laminated, and the thicknesses of the Ti film, the Pt film, and the Au film are, for example, 10 nm, 50 nm, and 100 nm, respectively.
It is.

As shown in FIG. 4, end face coat films 19 and 20 are formed on the front facet 17 and the rear facet 18, respectively. Here, the front-side end face coat film 19 is made of, for example, a single-layer Al ₂ O ₃ film, and has a thickness of, for example, 3λ / 4n (where λ is a laser) so that the front-side end face reflectivity becomes, for example, 10%. The oscillation wavelength and n are set near (refractive index). The rear end face coat film 20 is made of, for example, a multilayer film of Al ₂ O ₃ / TiO ₂ , and its thickness is set to, for example, four periods of λ / 4n so that the rear end face reflectivity becomes 95%, for example. ing.

Next, G according to the first embodiment of the present invention will be described.
A method for manufacturing an aN-based semiconductor laser will be described. First, an undoped GaN buffer layer 2 is grown on a c-plane sapphire substrate 1 whose surface has been previously cleaned by thermal cleaning or the like at a temperature of, for example, about 500 ° C. by a metal organic chemical vapor deposition (MOCVD) method. Using a lateral crystal growth technique such as
An undoped GaN layer 3 is grown at a growth temperature of 00 ° C.

Subsequently, on the undoped GaN layer 3,
By MOCVD, n-type GaN contact layer 4, n-type AlGaN cladding layer 5, n-type GaN optical guide layer 6, the active layer of undoped _{Ga 1-x In x N /} Ga 1-y In y N multi quantum well structure 7, undoped InGaN deterioration preventing layer 8, p-type AlGaN cap layer 9, p-type GaN optical waveguide layer 10, p-type AlGaN cladding layer 11, and p-type GaN
The contact layers 12 are sequentially grown. Here, the n-type GaN contact layer 4 which is a layer containing no In, the n-type AlG
aN cladding layer 5, n-type GaN optical waveguide layer 6, p-type AlG
aN cap layer 9, p-type GaN optical waveguide layer 10, p-type Al
GaN cladding layer 11 and p-type GaN contact layer 1
The growth temperature of 2 is set to for example 1000 ° C. approximately, the growth temperature of the _{Ga 1-x In x N /} Ga 1-y In y N active layer 7 of multiple quantum well structure is a layer containing In, for example 700 to 800
° C, for example, 730 ° C. The growth temperature of the undoped InGaN deterioration preventing layer 8 is set to, for example, 730 ° C. at the start of growth, which is the same as the growth temperature of the active layer 7, and then, for example, is increased linearly. The temperature is set to, for example, 835 ° C. like the temperature.

The raw materials for growing these GaN-based semiconductor layers are as follows:
For example, as a raw material of Ga, trimethylgallium ((C
Trimethylaluminum ((CH ₃ ) ₃ Al, TMA) as a raw material for H ₃ ) ₃ Ga, TMG) and Al, and trimethyl indium ((CH ₃ ) ₃ I as a raw material for In.
n, TMI), and NH ₃ as a raw material of N. As the carrier gas, for example, H ₂ is used. As for the dopant, for example, silane (SiH ₄ ) is used as an n-type dopant, and bis = methylcyclopentadienyl magnesium ((CH
₃ C ₅ H ₄ ) ₂ Mg) or bis = cyclopentadienyl magnesium ((C ₅ H ₅ ) ₂ Mg) is used.

Next, the c-plane sapphire substrate 1 on which the GaN-based semiconductor layer has been grown as described above is taken out of the MOCVD apparatus. Then, the entire surface, for example, the CVD method of the p-type GaN contact layer 12, a vacuum deposition method, after the example of thickness such as a sputtering method to form a 0.1 [mu] m SiO ₂ film (not shown), in the SiO ₂ film A resist pattern (not shown) having a predetermined shape corresponding to the shape of the mesa portion is formed by lithography, and using this resist pattern as a mask, for example, wet etching using a hydrofluoric acid-based etchant, or CF ₄ or CHF ₃ RIE using an etching gas containing fluorine such as
The O ₂ film is etched and patterned. Next, using the SiO ₂ film of a predetermined shape as a mask, etching is performed by, for example, RIE until the n-type GaN contact layer 4 is reached. As the RIE etching gas, for example, a chlorine-based gas is used. By this etching, n-type GaN
Upper layer of contact layer 4, n-type AlGaN cladding layer 5, n-type GaN optical waveguide layer 6, active layer 7, undoped In
GaN degradation prevention layer 8, p-type AlGaN cap layer 9, p
-Type GaN optical waveguide layer 10, p-type AlGaN cladding layer 11
And p-type GaN contact layer 12 is patterned into a mesa shape.

Next, the Si used as an etching mask
After the O ₂ film is removed by etching, for example, CVD on the entire surface of the substrate again, a vacuum deposition method, after the example of thickness such as a sputtering method to form a 0.2 [mu] m SiO ₂ film (not shown), the SiO ₂ film A resist pattern (not shown) having a predetermined shape corresponding to the ridge portion is formed thereon by lithography, and using this resist pattern as a mask,
For example, the SiO ₂ film is etched by wet etching using a hydrofluoric acid-based etchant or RIE using an etching gas containing fluorine such as CF ₄ or CHF _{3 to} have a shape corresponding to the ridge portion.

Next, using this SiO ₂ film as a mask, RI
The ridge 13 is etched by etching to a predetermined depth in the thickness direction of the p-type AlGaN cladding layer 11 by the E method.
To form As the RIE etching gas, for example, a chlorine-based gas is used.

Next, the Si used as an etching mask
After the O ₂ film is removed by etching, for example, CV
An insulating film 14 such as a SiO ₂ film having a thickness of, for example, 0.3 μm is formed by a method D, a vacuum evaporation method, a sputtering method, or the like.

Next, a resist pattern (not shown) is formed by lithography to cover the surface of the insulating film 14 excluding the n-side electrode formation region. Next, the opening 14b is formed by etching the insulating film 14 using the resist pattern as a mask.

Next, a Ti film, a Pt film, and an Au film are sequentially formed on the entire surface of the substrate by, for example, a vacuum deposition method while the resist pattern is left, and then the resist pattern is formed on the Ti film, Pt film formed thereon. It is removed together with the film and the Au film (lift-off). As a result, an n-side electrode 16 contacting the n-type GaN contact layer 4 through the opening 14b of the insulating film 14 is formed. Here, the thicknesses of the Ti film, Pt film and Au film constituting the n-side electrode 16 are, for example, 10 nm, 50 nm and 100 nm, respectively.
It is. Next, an alloy process for bringing the n-side electrode 16 into ohmic contact is performed.

Next, in a similar process, the insulating film 14 on the ridge 13 is removed by etching to form an opening 14 a, and the opening 14 a is formed in the same manner as the n-side electrode 16.
A p-side electrode 15 having a Pd / Pt / Au structure in contact with the p-type GaN contact layer 12 through a is formed. Next, an alloy process for bringing the p-side electrode 15 into ohmic contact is performed.

Next, the substrate on which the laser structure and the electrodes are formed as described above is cleaved into a bar shape as shown in FIG. 5, thereby obtaining the cavity end face 17 as shown in FIGS. 18 are formed. Next, the bar thus obtained is introduced into a processing chamber of an apparatus capable of generating plasma. Here, an electron cyclotron resonance (ECR) plasma apparatus which can perform plasma treatment and has an Al target and a Ti target and can perform film formation by a sputtering method is used.

Next, the inside of the processing chamber of the ECR plasma apparatus is sufficiently evacuated to a high vacuum, specifically, a pressure of, for example, 1 × 10 ⁻⁴ Pa or less, so that plasma is easily generated. First in this high vacuum, preferably 100 ° C. or higher,
More preferably, the bar is heated at a temperature of 200 ° C. or more and 400 ° C. or less, and moisture and contaminants adhering to the resonator end faces 17 and 18 are removed as much as possible. Next, an inert gas, for example, an argon (Ar) gas is introduced into the processing chamber,
An Ar plasma is generated. The pressure in the processing chamber when the Ar plasma is generated is preferably, for example, 1 ×
It is set to about 10 ⁻² Pa. In addition, since the plasma itself damages a semiconductor laser using a nitride III-V compound semiconductor, it is preferable not to apply a voltage to a portion holding the bar. In other words, only the self-bias generated naturally by the plasma generation is used. The energy of the plasma is preferably 100 kW · s or more and 500 kW · s or less. Also,
The plasma output at this time is preferably 1 kW or less, more preferably 800 W or less, still more preferably 500 W or less, and preferably 50 W or more. The exposure time is preferably at least 1 minute, more preferably at least 5 minutes, even more preferably at least 10 minutes. This Ar plasma treatment is performed without heating the bar with a heater or the like. This Ar plasma treatment is preferably performed on both the front-side resonator end face 17 and the rear-side resonator end face 18, but at a minimum, only the front-side resonator end face 17 from which light is extracted is performed. Thereby, the end face deterioration can be prevented to a considerable extent.

After treating the resonator end faces 17 and 18 with Ar plasma as described above, the resonator end faces 17 and 18 are processed.
The end face coating material is formed on the resonator end faces 17 and 18 to protect the end faces. Specifically, as shown in FIG. 4, an end face coating film 19 having the above-described material and thickness is formed on the front-side resonator end face 17, and the above-described material and thickness are formed on the rear-side resonator end face 18. The end face coat film 20 is formed. The formation of these end face coat films 19 and 20 is preferably performed by ECR.
After the above-described Ar plasma treatment in the processing chamber of the plasma apparatus, the plasma treatment is performed by ECR plasma sputtering in a vacuum state.

Next, in this manner, the end face coat film 19,
The bar on which 20 is formed is taken out of the apparatus, and the bar is pelletized to produce a laser chip as shown in FIGS. Thereafter, the laser chip is packaged to manufacture a GaN-based semiconductor laser having a target ridge structure and SCH structure.

FIG. 8 shows a life test of a GaN-based semiconductor laser in which the cavity end faces 17 and 18 were formed, heated at 200 ° C. in vacuum for 20 minutes, and subsequently subjected to Ar plasma treatment at 500 W for 10 minutes. The results are shown. For comparison, FIG. 9 shows the results of a life test of a GaN-based semiconductor laser in which these treatments were not performed on the cavity end faces 17 and 18. However, the life test was performed at 60 ° C. and 30 mW. As is apparent from a comparison between FIGS. 8 and 9, in the GaN-based semiconductor laser without the heat treatment and the Ar plasma treatment (FIG. 9), an increase in the operating current is observed in a short time after energization is started, and the breakdown is caused. However, in the GaN-based semiconductor laser (FIG. 8) that has been subjected to the heat treatment and the Ar plasma treatment, the operating current hardly increases during energization, and the life is significantly extended.

FIG. 10 shows that after forming the cavity end faces 17 and 18, heating is performed at 200 ° C. for 20 minutes in a vacuum.
Next, the measurement results of the optical output (L) -current (I) characteristics of the GaN-based semiconductor laser subjected to Ar plasma treatment at 500 W for 10 minutes after energizing for 140 hours at 60 ° C. and 30 mW are shown. For comparison, FIG. 11 shows measurement results of similar LI characteristics of a GaN-based semiconductor laser in which these treatments have not been performed on the cavity end faces 17 and 18. However, the measurement was performed under the condition of 25 ° C. and continuous oscillation. FIG. 10 and FIG.
1 clearly shows that the GaN-based semiconductor laser not subjected to the heat treatment and the Ar plasma treatment (FIG. 1)
In 1), almost ideal LI characteristics were obtained before energization, but after 140 hours of energization, the LI characteristics deteriorated significantly, resulting in a decrease in kink level, an increase in operating current, and an increase in external quantum efficiency. Of the GaN-based semiconductor laser (FIG. 10) that has been subjected to the heat treatment and the Ar plasma treatment,
The -I characteristic has hardly changed from that before energization, and none of the reduction of the kink level, the increase of the operating current, the reduction of the external quantum efficiency, the reduction of the thermal saturation level, and the like have occurred.

After forming the cavity end faces 17 and 18, heating was performed in vacuum at 200 ° C. for 20 minutes, and subsequently, Ar plasma treatment was performed at 500 W for 10 minutes, and a life test (60 ° C., 30 mW) of the GaN-based semiconductor laser was performed. ), The cross sections of the end face coating films 19 and 20 of the resonator end faces 17 and 18 were observed by a transmission electron microscope. As a result, no peeling of the end face coating films 19 and 20 was observed, and good adhesion was obtained. Was confirmed. On the other hand, when a life test (60 ° C., 30 mW) was performed on a GaN-based semiconductor laser that had not been subjected to the heat treatment and the Ar plasma treatment, similar observations were made, and peeling of the end face coat films 19 and 20 was observed. It was confirmed that sex was bad.

The reason why the adhesion between the end face coat films 19 and 20 is good in the GaN-based semiconductor laser which has been subjected to the heat treatment and the Ar plasma treatment as described above has not been completely elucidated at present. The following can be considered as a model. That is, as shown in FIG. 12A, the cavity facets 17 and 18 formed by cleavage have irregularities of the order of nm (hereinafter referred to as “nano roughness”). The resonator end faces 17, 18
Is subjected to Ar plasma treatment, as shown in FIG.
Nano roughness is reduced or almost eliminated by the sputtering effect due to the collision of Ar ions, and the flatness of the cavity end faces 17 and 18 is improved. For this reason, when the end face coat films 19 and 20 are formed on the resonator end faces 17 and 18 having the improved flatness, it is considered that good adhesion is obtained.

As described above, according to the first embodiment, after forming the resonator end faces 17 and 18, heat treatment is performed in a vacuum to purify the resonator end faces 17 and 18 as much as possible. Ar plasma treatment is performed on the surfaces 17 and 18 to perform more complete cleaning, and thereafter, the end surfaces of the resonators 17 and 18 are coated with the end surface coating films 19 and 2 without being exposed to the air.
0, these end face coat films 19, 2
The adhesion of 0 can be greatly improved. For this reason, the end faces of the resonator end faces 17 and 18 can be effectively suppressed from deteriorating, an increase in operating current during energization can be suppressed, and the life of the GaN-based semiconductor laser can be greatly improved. it can. Further, the yield of the GaN-based semiconductor laser can be improved. In addition, a temporal change in the LI characteristic can be effectively suppressed, and the reliability of the GaN-based semiconductor laser can be improved. Further, since the increase in the operating current is reduced, the increase in the relative noise intensity (RIN) during energization can be suppressed.

Next, G according to the second embodiment of the present invention will be described.
A method for manufacturing an aN-based semiconductor laser will be described. First
In the second embodiment, after the resonator end faces 17 and 18 are formed, the heat treatment is performed in a vacuum before performing the Ar plasma treatment on the resonator end faces 17 and 18. However, in the second embodiment, Does not perform this heat treatment. That is, after the resonator end faces 17 and 18 are formed, the resonator end faces 17 and 18 are immediately subjected to Ar plasma treatment. The conditions for this Ar plasma treatment are the same as in the first embodiment. Other points are the same as in the first embodiment. According to the second embodiment, advantages similar to those of the first embodiment can be obtained.

Next, G according to the third embodiment of the present invention will be described.
A method for manufacturing an aN-based semiconductor laser will be described. In the third embodiment, after forming the resonator end faces 17 and 18, the resonator end faces 17 and 18 are subjected to Ar plasma treatment. At this time, the bar is preferably set to 100 ° C. or more, more preferably. Is heated to a temperature of 200 ° C. or more, preferably 400 ° C. or less. Other points are the same as in the first embodiment. According to the third embodiment, advantages similar to those of the first embodiment can be obtained.

Next, G according to the fourth embodiment of the present invention will be described.
A method for manufacturing an aN-based semiconductor laser will be described. In the fourth embodiment, as in the first embodiment,
The substrate on which the laser structure and the electrodes are formed is cleaved into a bar shape to form cavity end faces 17 and 18.

Next, the bar thus obtained is introduced into a processing chamber of an apparatus capable of performing end face coating in a vacuum. Here, an ECR plasma apparatus that includes an Al target and a Ti target and can form a film by a sputtering method is used.

Next, the processing chamber of the ECR plasma apparatus is sufficiently evacuated to a high vacuum, specifically, for example, a pressure of 1 × 10 ⁻⁴ Pa or less, so that plasma is easily generated. First in this high vacuum, preferably 100 ° C. or higher,
More preferably, the bar is heated at a temperature of 200 ° C. or more and 400 ° C. or less, and moisture and contaminants adhering to the resonator end faces 17 and 18 are removed as much as possible. Next, for example, Ar gas and O ₂ gas are introduced into the processing chamber to generate Ar plasma and oxygen plasma. Then, by performing ECR plasma sputtering using an Al target, as shown in FIG. 13, an AlO _x film 21 (provided that 0 <x <1.
5) is formed. Here, forming the AlO _x film 21 on both cavity end faces 17 and 18, the AlO _x film 21
Can be obtained at least on the front end face 17 of the resonator. The AlO _x film 21 may be a continuous film or may be made of fine particles in the form of islands (islands). This Al
When the O _x film 21 is a continuous film, particularly when the value of x is small, it is preferably 5 nm or less, more preferably 5 nm or less, in order to sufficiently suppress the absorption of light by the AlO _x film 21 during operation of the semiconductor laser. Is selected to be 2 nm or less. On the other hand, this A
When the 10 _x film 21 is made of fine particles, the height of the fine particles is selected to be, for example, 10 nm or less, depending on the value of x. Whether the AlO _x film 21 is a continuous film or a fine particle can be easily controlled by film forming conditions (temperature, thickness, etc.).

After the AlO _x film 21 is formed on the resonator end faces 17 and 18 as described above, as shown in FIG. 14, the front side resonator end face 17 is formed in the same manner as in the first embodiment. An end face coat film 19 is formed via an AlO _x film 21 and an end face coat film 20 is formed on the rear-side resonator end face 18 via an AlO _x film 21. The formation of these end face coat films 19 and 20 is preferably performed by ECR plasma sputtering in a processing chamber of an ECR plasma apparatus, in a vacuum state, following the formation of the AlO _x film 21 described above.

Next, the end surface coat film 19,
A laser chip is manufactured by pelletizing the bar on which 20 is formed, and the laser chip is packaged to manufacture a GaN-based semiconductor laser having a target ridge structure and SCH structure.

After the cavity end faces 17 and 18 are formed, heating is performed at 200 ° C. for 20 minutes in a vacuum. Subsequently, an AlO _x film 21 is formed on the cavity end faces 17 and 18 as an adhesion layer. G formed with coating films 19 and 20
When the life test of the aN-based semiconductor laser was performed, the same result as in FIG. 8 was obtained, and it was found that the operating current hardly increased during the energization, and the life was significantly extended.

After the resonator end faces 17 and 18 are formed, heating is performed at 200 ° C. for 20 minutes in a vacuum, and then an AlO _x film 21 is formed on the resonator end faces 17 and 18 as an adhesion layer. The optical output (L) -current (I) characteristics of the GaN-based semiconductor laser having the end face coat films 19 and 20 formed thereon after being energized for 140 hours under the conditions of 60 ° C. and 30 mW were measured. Is obtained, and 14
Even after the current supply for 0 hours, the LI characteristic hardly changes from that before the current supply, and neither a decrease in the kink level, an increase in the operating current, a decrease in the external quantum efficiency, nor a decrease in the thermal saturation level occurs. I understood that.

After the resonator end faces 17 and 18 are formed, heating is performed at 200 ° C. for 20 minutes in a vacuum. Subsequently, an AlO _x film 21 is formed on the resonator end faces 17 and 18 as an adhesion layer, and the end faces are formed thereon. G formed with coating films 19 and 20
After the life test (60 ° C., 30 mW) of the aN-based semiconductor laser, the end face coat films 19 on the cavity end faces 17, 18
Observation of the cross section of 20 with a transmission electron microscope showed that
Peeling of the end coat films 19 and 20 was not observed, and it was confirmed that good adhesion was obtained. On the other hand, Ga which has not been subjected to the heat treatment and the formation of the end face coat films 19 and 20 on the cavity end faces 17 and 18 via the AlO _x film 21 is not performed.
Life test (60 ° C, 30m
When the same observation was performed after W), peeling of the end face coat films 19 and 20 was observed, and it was confirmed that the adhesion was poor.

For the GaN-based semiconductor laser in which the peeling of the end face coat films 19 and 20 was not observed, the end face coat films 19 and 20 were removed from the cavity end faces 17 and 18.
When the cross-sectional structure of the lowermost layer of the Al ₂ O ₃ film was observed with a transmission electron microscope, a kind of transition layer was present between the cavity end faces 17 and 18 and this Al ₂ O ₃ film. I understood that. Then, when the composition of this transition layer was examined by electron energy loss spectroscopy (EELS), Al
AlO _x film 21 having an intermediate composition between Al ₂ O ₃ and Al ₂ O ₃
It turned out to be. Considering this result, this A
It can be considered that the presence of the 10 _x film 21 plays a role of improving the adhesion between the end face coat films 19 and 20.

As described above, the heat treatment and the cavity facet 1
End face coating film 1 via AlO _x film 21 to 7 and 18
As one model for explaining the reason why the adhesion between the end face coat films 19 and 20 is good in the GaN-based semiconductor laser on which the formations 9 and 20 are formed, the following model can be considered.
That is, as shown in FIG. 15A, the nano-roughness exists on the cavity end faces 17 and 18 formed by cleavage, as described above. This resonator end face 1
When the formation of AlO _x film 21 on layers 7 and 18 is started, FIG.
As shown in FIG. 5B, the nano roughness is reduced or almost eliminated by the sputtering effect due to the collision of Ar ions, the flatness of the resonator end faces 17 and 18 is improved, and Al and O are added to the resonator end faces 17 and 18. By Al
An _Ox film 21 is formed. It is considered that due to the improvement of the flatness of the resonator end faces 17 and 18 and the presence of the AlO _x film 21, good adhesion between the end face coat films 19 and 20 can be obtained.

As described above, according to the fourth embodiment, after forming the resonator end faces 17 and 18, heat treatment is performed in a vacuum to purify the resonator end faces 17 and 18 as much as possible. The AlO _x film 21 is formed by ECR plasma sputtering using Ar gas and O ₂ gas for 17 and 18.
Are formed, and the end face coat films 19 and 20 are formed on the end faces 17 and 18 of the resonator without being exposed to the air on the way. Therefore, the adhesion of the end face coat films 19 and 20 is greatly improved. Can be planned. For this reason, the end faces of the resonator end faces 17 and 18 can be effectively prevented from deteriorating, and an increase in operating current during energization can be suppressed.
The life of the aN-based semiconductor laser can be greatly improved. Further, the yield of the GaN-based semiconductor laser can be improved. In addition, a temporal change in the LI characteristic can be effectively suppressed, and the reliability of the GaN-based semiconductor laser can be improved. Further, since the increase in the operating current is reduced, the increase in RIN during energization can be suppressed.

Next, G according to the fifth embodiment of the present invention will be described.
A method for manufacturing an aN-based semiconductor laser will be described. In the fifth embodiment, as in the first embodiment,
After the substrate on which the laser structure and the electrodes are formed is cleaved into a bar shape to form resonator end faces 17 and 18, the bar is moved to a processing chamber of a plasma processing apparatus, and the resonator end faces 17 and 18 are set in the processing chamber. Ar plasma treatment is performed.
Next, AlO _x bar making this Ar plasma treatment was vacuum transferred from the processing chamber of a plasma processing apparatus to the deposition chamber of the deposition apparatus, the cavity end face 17 by the film forming chamber, for example, a sputtering method A film 21 is formed, and subsequently, end face coat films 19 and 20 are formed thereon.

The other points are the same as those of the first and fourth embodiments, and the description is omitted. According to the fifth embodiment, advantages similar to those of the fourth embodiment can be obtained.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above embodiments, and various modifications based on the technical concept of the present invention are possible.

For example, the numerical values, structures, substrates, raw materials, processes, and the like described in the above-described first to fifth embodiments are merely examples, and different numerical values, structures, substrates, and raw materials may be used as necessary. , A process or the like may be used.

More specifically, for example, in the above-described first to fifth embodiments, an ECR plasma apparatus is used for the plasma processing, but a different plasma apparatus may be used if necessary. . Further, the end face coating films 19 and 20
The method other than ECR plasma sputtering may be used for the formation.

Specifically, for example, in the above-described first to fifth embodiments, an n-type layer forming a laser structure is first stacked on a substrate, and a p-type layer is stacked thereon. However, the stacking order may be reversed so that a p-type layer is first stacked on a substrate and an n-type layer is stacked thereon.

In the first to fifth embodiments, the c-plane sapphire substrate is used. However, if necessary, a SiC substrate, a Si substrate, a spinel substrate, a thick GaN substrate may be used.
A substrate composed of layers may be used. Further, instead of the GaN buffer layer, an AlN buffer layer or an AlGaN buffer layer may be used.

In the first to fifth embodiments, the case where the present invention is applied to the manufacture of a GaN-based semiconductor laser having a SCH structure has been described.
For example, GaN with DH (Double Heterostructure) structure
Of course, it may be applied to the manufacture of GaN-based light emitting diodes,
Further, the present invention may be applied to an electron traveling device using a nitride III-V compound semiconductor such as a GaN-based FET or a GaN-based heterojunction bipolar transistor (HBT).

Further, in the above-described first to fifth embodiments, H ₂ gas is used as a carrier gas when growing by MOCVD. However, if necessary, another carrier gas, for example, H ₂ gas is used. A mixed gas of ₂ and N ₂ or He or Ar gas may be used.

[0109]

As described above, according to the present invention, after forming a cavity facet of a semiconductor laser, the cavity facet is exposed to a plasma atmosphere of an inert gas, Heating in a gas atmosphere at a temperature of 30 ° C. or more and 700 ° C. or less and exposure of the inert gas on the cavity end face to the plasma atmosphere, or removal of the inert gas on the cavity end face at a temperature of 30 ° C. or more and 700 ° C. or less By exposing to a plasma atmosphere, it is possible to easily manufacture a semiconductor laser using a nitride III-V compound semiconductor that has a very small increase in operating current during energization, a long life, and a very little change over time. Can be manufactured.

Further, according to the present invention, after forming the end face of the semiconductor device, this end face is exposed to an inert gas plasma atmosphere, or 30 to 700 ° C. in a vacuum or an inert gas atmosphere. Heating at a temperature of and exposure to an inert gas plasma atmosphere at the end face, or exposure to an inert gas plasma atmosphere at the end face at a temperature of 30 ° C. or more and 700 ° C. or less. The end face formed by processing the nitride-based III-V compound semiconductor can be improved, and the adhesion can be improved when the end face is coated with the end face.

Further, according to the present invention, after forming the cavity facet of the semiconductor laser or the facet of the semiconductor device,
Since the end face of the resonator or the end face is coated with an adhesion layer via an adhesion layer, the adhesion of the end face coat film can be improved, the operating current during energization is extremely small, and the life is long. The semiconductor laser using nitride-based III-V compound semiconductors and other semiconductors with very little change over time can be easily manufactured.
Alternatively, a highly reliable semiconductor device can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a relationship between an average height of fine particles and an energy reflectance when fine particles causing irregularities are formed on a front end face of a resonator.

FIG. 2 is a schematic diagram illustrating a relationship between an average height of fine particles and a change in energy reflectance when fine particles causing irregularities are formed on a front end face of a resonator;

FIG. 3 is a sectional view of a GaN-based semiconductor laser manufactured according to the first to fourth embodiments of the present invention, taken along a direction perpendicular to the cavity length direction.

FIG. 4 is a cross-sectional view of a GaN-based semiconductor laser manufactured according to the first to fourth embodiments of the present invention, taken in a direction parallel to the cavity length direction.

FIG. 5 is a perspective view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 6 is a perspective view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 7 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 8 shows a G manufactured according to the first embodiment of the present invention.
FIG. 4 is a schematic diagram illustrating a result of a life test of an aN-based semiconductor laser.

FIG. 9 shows a G manufactured according to the first embodiment of the present invention.
GaN manufactured for comparison with aN-based semiconductor laser
FIG. 7 is a schematic diagram illustrating a result of a life test of a system semiconductor laser.

FIG. 10 is a schematic diagram illustrating measurement results of LI characteristics of a GaN-based semiconductor laser manufactured according to the first embodiment of the present invention.

FIG. 11 shows a Ga manufactured for comparison with a GaN-based semiconductor laser manufactured according to the first embodiment of the present invention.
FIG. 9 is a schematic diagram illustrating measurement results of LI characteristics of an N-based semiconductor laser.

FIG. 12 is a schematic diagram for explaining the reason why the adhesion of the end face coat film is improved by Ar treatment in the first embodiment of the present invention.

FIG. 13 is a cross-sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the fourth embodiment of the present invention.

FIG. 14 is a cross-sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the fourth embodiment of the present invention.

FIG. 15 is a schematic diagram for explaining the reason why the adhesion of an end face coat film is improved by forming an AlO _x film on a resonator end face in a fourth embodiment of the present invention.

[Explanation of symbols]

1 ... c-plane sapphire substrate, 4 ... n-type GaN contact layer, 5 ... n-type AlGaN cladding layer, 6 ...
· N-type GaN optical waveguide layer, 7 ··· active layer, 8 ··· undoped InGaN degradation prevention layer, 9 ··· p-type AlGaN
Cap layer, 10 ... p-type GaN optical waveguide layer, 11 ...
-P-type AlGaN cladding layer, 12 ... p-type GaN contact layer, 13 ... ridge, 14 ... insulating film, 1
5 ... p-side electrode, 16 ... n-side electrode, 17, 18
..Resonator end faces, 19, 20 ... end face coating films, 21
... AlO _x film

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masao Ikeda 3-53-2 Shiratori, Shiroishi City, Miyagi Prefecture Inside Sony Shiroishi Semiconductor Co., Ltd. (72) Inventor Yoshio Ohto 3-53-2 Shiratori, Shiraishi City, Miyagi Prefecture Inside Sony Shiroishi Semiconductor Co., Ltd. (72) Inventor Shiro Uchida 3-53-3, Shiratori, Shiroishi City, Miyagi Prefecture Inside Sony Shiroishi Semiconductor Co., Ltd. No. within Sony Corporation (72) Inventor Etsuo Morita 6-35, Kita Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 5F004 AA14 BA14 BD05 CA06 DA23 EB08 FA08 5F073 AA46 AA74 AA83 CA07 CB05 CB07 CB19 DA07 DA16 DA35 EA28

Claims (117)

[Claims] 1. A method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, comprising: forming a cavity facet of the semiconductor laser; and exposing the cavity facet to a plasma atmosphere of an inert gas. A method for manufacturing a semiconductor laser, characterized in that: 2. An end face coating is applied to the resonator end face without exposing the resonator end face to the atmosphere after exposing the inert gas to a plasma atmosphere. 2. A method for manufacturing a semiconductor laser according to item 1. 3. The method according to claim 1, wherein the inert gas is a rare gas and / or a nitrogen gas. 4. The method according to claim 3, wherein the rare gas is an argon gas. 5. The method according to claim 1, wherein the energy of the plasma is not less than 0.5 kilowatt seconds and not more than 900 kilowatt seconds. 6. The method according to claim 5, wherein an output of said plasma is 50 watts or more. 7. The method according to claim 5, wherein an output of said plasma is 100 watts or more. 8. The method according to claim 5, wherein an output of said plasma is 1000 watts or less. 9. The method according to claim 5, wherein the output of the plasma is 800 watts or less. 10. The method according to claim 5, wherein the output of the plasma is 500 watts or less. 11. The method according to claim 5, wherein the exposure time of the inert gas to the plasma atmosphere is 10 seconds or more. 12. The exposure time of the inert gas to the plasma atmosphere is 1 minute or more.
The manufacturing method of the semiconductor laser according to the above. 13. The exposure time of said inert gas to a plasma atmosphere is 5 minutes or more.
The manufacturing method of the semiconductor laser according to the above. 14. The method according to claim 5, wherein the exposure time of the inert gas to the plasma atmosphere is 10 minutes or more. 15. The method of manufacturing a semiconductor laser according to claim 1, wherein the pressure of the processing chamber before forming the plasma atmosphere of the inert gas is 1 × 10 ⁻⁴ Pa or less. 16. The pressure in the processing chamber after forming the plasma atmosphere of the inert gas is 0.8 × 10 ⁻² Pa or more.
2. The method according to claim 1, wherein the pressure is not more than 2 × 10 ⁻² Pa. 17. The method according to claim 1, wherein the object to be processed is maintained in a self-biased state. 18. A method of manufacturing a semiconductor laser using a nitride-based III-V compound semiconductor, wherein after forming a cavity facet of the semiconductor laser, the semiconductor laser is heated to 30 ° C. or more and 700 ° C. in vacuum or an inert gas atmosphere A method of manufacturing a semiconductor laser, comprising: a step of heating at the following temperature; and a step of forming a cavity facet of the semiconductor laser and exposing the cavity facet to a plasma atmosphere of an inert gas after forming the cavity facet. . 19. After the heating and the exposure of the inert gas to the plasma atmosphere, an end face coating is applied to the end face of the resonator without exposing the end face of the resonator to the atmosphere. 19. The method for manufacturing a semiconductor laser according to claim 18, wherein: 20. The method according to claim 18, wherein the inert gas is a rare gas and / or a nitrogen gas. 21. The method according to claim 20, wherein the rare gas is an argon gas. 22. The method according to claim 18, wherein the energy of the plasma is not less than 0.5 kilowatt seconds and not more than 900 kilowatt seconds. 23. The method according to claim 22, wherein the output of the plasma is 50 watts or more. 24. The method according to claim 22, wherein an output of said plasma is 100 watts or more. 25. The method according to claim 22, wherein the output of the plasma is 1000 watts or less. 26. The method according to claim 22, wherein the output of the plasma is 800 watts or less. 27. The method according to claim 22, wherein an output of said plasma is 500 watts or less. 28. The method according to claim 22, wherein the exposure time of the inert gas to the plasma atmosphere is 10 seconds or more. 29. The exposure time of the inert gas to the plasma atmosphere is 1 minute or more.
3. The method for manufacturing a semiconductor laser according to item 2. 30. The exposure time of the inert gas to the plasma atmosphere is 5 minutes or more.
3. The method for manufacturing a semiconductor laser according to item 2. 31. The method according to claim 22, wherein the exposure time of the inert gas to the plasma atmosphere is 10 minutes or more. 32. The method of manufacturing a semiconductor laser according to claim 18, wherein the pressure in the processing chamber before forming the plasma atmosphere of the inert gas is 1 × 10 ⁻⁴ Pa or less. 33. The pressure of the processing chamber after forming the plasma atmosphere of the inert gas is 0.8 × 10 ⁻² Pa or more.
19. The pressure is set to 2 × 10 ⁻² Pa or less.
The manufacturing method of the semiconductor laser according to the above. 34. The method for manufacturing a semiconductor laser according to claim 18, wherein the object is held in a self-biased state. 35. The method according to claim 18, wherein the heating is performed at a temperature of 30 ° C. or more and 400 ° C. or less. 36. The method according to claim 18, wherein the heating is performed at a temperature of 50 ° C. or more and 700 ° C. or less. 37. The method according to claim 18, wherein the heating is performed at a temperature of 50 ° C. or more and 400 ° C. or less. 38. The method according to claim 18, wherein the heating is performed at a temperature of 100 ° C. or more and 700 ° C. or less. 39. The method according to claim 18, wherein the heating is performed at a temperature of 100 ° C. or more and 400 ° C. or less. 40. The method according to claim 18, wherein the vacuum pressure is 1 × 10 ⁻⁴ Pa or less. 41. The method according to claim 18, wherein the inert gas is a rare gas and / or a nitrogen gas. 42. The method according to claim 41, wherein the rare gas is an argon gas. 43. A method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, comprising: forming a cavity facet of the semiconductor laser;
A method for manufacturing a semiconductor laser, wherein the semiconductor laser is exposed to a plasma atmosphere of an inert gas at a temperature of from 700C to 700C. 44. An end face coating is applied to the resonator end face without exposing the resonator end face to the atmosphere after exposing the inert gas to a plasma atmosphere. 44. The method for manufacturing a semiconductor laser according to 43. 45. The method according to claim 43, wherein the semiconductor laser is exposed to a plasma atmosphere of the inert gas at a temperature of 30 ° C. or more and 400 ° C. or less. 46. The method of manufacturing a semiconductor laser according to claim 43, wherein the semiconductor laser is exposed to a plasma atmosphere of the inert gas at a temperature of 50 ° C. or more and 700 ° C. or less. 47. The method according to claim 43, wherein the semiconductor laser is exposed to a plasma atmosphere of the inert gas at a temperature of 50 ° C. or more and 400 ° C. or less. 48. The method according to claim 43, wherein the semiconductor laser is exposed to a plasma atmosphere of the inert gas at a temperature of 100 ° C. or more and 700 ° C. or less. 49. The method according to claim 43, wherein the semiconductor laser is exposed to a plasma atmosphere of the inert gas at a temperature of 100 ° C. or more and 400 ° C. or less. 50. The method according to claim 43, wherein the inert gas is a rare gas and / or a nitrogen gas. 51. The method according to claim 50, wherein the rare gas is an argon gas. 52. The method according to claim 43, wherein the energy of the plasma is not less than 0.5 kilowatt seconds and not more than 900 kilowatt seconds. 53. The method according to claim 52, wherein the output of the plasma is 50 watts or more. 54. The method according to claim 52, wherein an output of said plasma is 100 watts or more. 55. The method according to claim 52, wherein the output of said plasma is 1000 watts or less. 56. The method according to claim 52, wherein the output of said plasma is 800 watts or less. 57. The method according to claim 52, wherein the output of said plasma is 500 watts or less. 58. The method of manufacturing a semiconductor laser according to claim 52, wherein the exposure time of the inert gas to the plasma atmosphere is 10 seconds or more. 59. The exposure time of the inert gas to the plasma atmosphere is one minute or more.
3. The method for manufacturing a semiconductor laser according to item 2. 60. The exposure time of the inert gas to the plasma atmosphere is 5 minutes or more.
3. The method for manufacturing a semiconductor laser according to item 2. 61. The method according to claim 52, wherein the exposure time of the inert gas to the plasma atmosphere is 10 minutes or more. 62. The method for manufacturing a semiconductor laser according to claim 43, wherein the pressure of the processing chamber before forming the plasma atmosphere of the inert gas is set to 1 × 10 ⁻⁴ Pa or less. 63. The pressure of the processing chamber after forming the plasma atmosphere of the inert gas is 0.8 × 10 ⁻² Pa or more.
44. The pressure is set to 2 × 10 ⁻² Pa or less.
The manufacturing method of the semiconductor laser according to the above. 64. The method according to claim 43, wherein the object is held in a self-biased state. 65. A method of manufacturing a semiconductor laser using a nitride-based III-V compound semiconductor, comprising: processing a substrate on which a semiconductor laser structure using a nitride-based III-V compound semiconductor is formed into a bar shape. Forming a cavity facet by exposing the cavity facet to a plasma atmosphere of an inert gas. 66. A method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, comprising: processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape. Forming a cavity end face by heating at a temperature of 30 ° C. or more and 700 ° C. or less in a vacuum or an inert gas atmosphere, and forming a semiconductor laser structure using a nitride III-V compound semiconductor. Forming a resonator end face by processing the substrate thus formed into a bar shape, and exposing the resonator end face to a plasma atmosphere of an inert gas. 67. A method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, comprising: processing a substrate on which a semiconductor laser structure using a nitride III-V compound semiconductor is formed into a bar shape. Forming a cavity facet by exposing the cavity facet to a plasma atmosphere of an inert gas at a temperature of 30 ° C. or more and 700 ° C. or less. 68. A method for manufacturing a semiconductor device having an end face formed by processing a nitride III-V compound semiconductor, comprising: forming the end face, exposing the end face to a plasma atmosphere of an inert gas. A method of manufacturing a semiconductor device. 69. A method for manufacturing a semiconductor device having an end face formed by processing a nitride-based III-V compound semiconductor, comprising: forming the end face, forming the end face at 30 ° C. in a vacuum or in an inert gas atmosphere. A method for manufacturing a semiconductor device, comprising: a step of heating at a temperature of at least 700 ° C. and a step of exposing the end face to a plasma atmosphere of an inert gas after forming the end face. 70. A method of manufacturing a semiconductor device having an end face formed by processing a nitride-based III-V compound semiconductor, comprising: forming the end face;
A method of manufacturing a semiconductor device, comprising exposing the semiconductor device to an inert gas plasma atmosphere at the following temperature. 71. A semiconductor laser using a nitride III-V compound semiconductor, wherein an end face coat film is formed on an end face of the resonator via an adhesion layer. 72. The semiconductor laser according to claim 71, wherein said adhesion layer is formed on a region including at least a light emitting portion on said cavity facet. 73. The semiconductor laser according to claim 71, wherein said adhesion layer is formed of a continuous film. 74. The semiconductor laser according to claim 73, wherein said continuous film has a thickness of 10 nm or less. 75. The semiconductor laser according to claim 73, wherein said continuous film has a thickness of 5 nm or less. 76. The semiconductor laser according to claim 73, wherein said continuous film has a thickness of 2 nm or less. 77. The semiconductor laser according to claim 73, wherein said continuous film is formed so as not to extend over an n-type layer and a p-type layer forming a semiconductor laser structure. 78. The semiconductor laser according to claim 71, wherein said adhesion layer is made of fine particles. 79. The energy reflectivity when the resonator facet is flat is R ₀ , and the energy reflectivity when the close contact layer made of the fine particles is formed on the resonator facet is R ₀ .
_Assuming that _s , the oscillation wavelength is λ, the refractive index of the fine particles is n, and the average height of the fine particles is σ, R obtained from the formula R _s = R ₀ exp [− (4πn (σ / λ)) ² ] _79. The semiconductor laser according to claim 78, wherein σ is set so that _s is equal to or less than a predetermined value. 80. The semiconductor laser according to claim 71, wherein said adhesion layer comprises a continuous film and fine particles thereon. 81. The adhesion layer is made of Al, Ti, Zr, H
73. At least one element selected from the group consisting of f, Ta, Zn and Si.
A semiconductor laser as described in the above. 82. The adhesion layer is made of Al, Ti, Zr, H
72. The semiconductor laser according to claim 71, comprising a substance containing at least one element selected from the group consisting of f, Ta, Zn, and Si, and oxygen and / or nitrogen. 83. The semiconductor laser according to claim 71, wherein said end face coat film is formed of a single-layer or multi-layer dielectric film. 84. The adhesion layer and the dielectric film in contact with the adhesion layer include at least one element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn, and Si. 84. The semiconductor laser according to claim 83. 85. The contact layer and the dielectric film in contact with the contact layer include at least one and the same element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn and Si. 84. The semiconductor laser according to claim 83. 86. The dielectric film in contact with the adhesion layer is formed of A
consists l ₂ O _3, a semiconductor laser according to claim 83, wherein said adhesion layer is characterized by comprising Al and O. 87. In a method of manufacturing a semiconductor laser using a nitride III-V compound semiconductor, after forming a cavity facet of the semiconductor laser, the cavity facet is subjected to an end face coating via an adhesion layer. A method for manufacturing a semiconductor laser, characterized in that: 88. The method for manufacturing a semiconductor laser according to claim 87, wherein said adhesion layer is formed on a region including at least a light emitting portion on said cavity end face. 89. The method according to claim 87, wherein the adhesion layer is formed of a continuous film. 90. The method according to claim 89, wherein the thickness of the continuous film is 10 nm or less. 91. The method according to claim 89, wherein said continuous film has a thickness of 5 nm or less. 92. The method according to claim 89, wherein the thickness of the continuous film is 2 nm or less. 93. The method of manufacturing a semiconductor laser according to claim 89, wherein said continuous film is formed so as not to extend over an n-type layer and a p-type layer forming a semiconductor laser structure. 94. The method according to claim 87, wherein the adhesion layer is made of fine particles. The energy reflectance when the resonator facet is flat is R ₀ , and the energy reflectance when the adhesion layer made of the fine particles is formed on the resonator facet is R ₀ .
_Assuming that _s , the oscillation wavelength is λ, the refractive index of the fine particles is n, and the average height of the fine particles is σ, R obtained from the formula R _s = R ₀ exp [− (4πn (σ / λ)) ² ] _The method for manufacturing a semiconductor laser according to claim 94, wherein σ is set so that _s is equal to or less than a predetermined value. 96. The adhesion layer is made of Al, Ti, Zr, H
87. At least one element selected from the group consisting of f, Ta, Zn and Si.
The manufacturing method of the semiconductor laser according to the above. 97. The adhesion layer is made of Al, Ti, Zr, H
88. The method for manufacturing a semiconductor laser according to claim 87, comprising a substance containing at least one element selected from the group consisting of f, Ta, Zn and Si, and oxygen and / or nitrogen. 98. The method for manufacturing a semiconductor laser according to claim 87, wherein said end face coat film is formed of a single-layer or multi-layer dielectric film. 99. The adhesive layer and the dielectric film in contact with the adhesive layer include at least one element selected from the group consisting of Al, Ti, Zr, Hf, Ta, Zn and Si. A method for manufacturing a semiconductor laser according to claim 98. 100. The adhesion layer and the dielectric film in contact with the adhesion layer are formed of Al, Ti, Zr, Hf, Ta, and Zn.
100. The method of manufacturing a semiconductor laser according to claim 98, comprising at least one same element selected from the group consisting of Si and Si. 101. The method according to claim 98, wherein said dielectric film in contact with said adhesion layer is made of Al ₂ O ₃ , and said adhesion layer is made of Al and O. 102. After forming the resonator end face, after or while exposing the resonator end face to a plasma atmosphere of an inert gas, the adhesion layer is formed on the resonator end face. A method for manufacturing a semiconductor laser according to claim 87. 103. The method of manufacturing a semiconductor laser according to claim 102, wherein after forming the adhesion layer, an end face coating is applied to the end face of the resonator without exposing the end face of the resonator to the atmosphere. Method. 104. The energy of the plasma is 0.5
103. The method for manufacturing a semiconductor laser according to claim 102, wherein the time is not less than kilowatt seconds and not more than 900 kilowatt seconds. 105. A method of manufacturing a semiconductor laser using a nitride-based III-V compound semiconductor, comprising: processing a substrate on which a semiconductor laser structure using a nitride-based III-V compound semiconductor is formed into a bar shape. Forming a cavity end face by using an adhesive layer, and then applying an end face coating to the cavity end face via an adhesion layer. 106. A semiconductor device having an end face formed by processing a nitride III-V compound semiconductor, wherein an end face coat film is formed on the end face via an adhesion layer. Semiconductor device. 107. A method of manufacturing a semiconductor device having an end face formed by processing a nitride III-V compound semiconductor, comprising: forming the end face; and coating the end face with an adhesion layer via an adhesion layer. A method of manufacturing a semiconductor device, wherein the method is performed. 108. A semiconductor laser using a group III-V compound semiconductor, wherein an end face coat film is formed on an end face of the resonator via an adhesion layer. 109. A method of manufacturing a semiconductor laser using a III-V compound semiconductor, wherein after forming a cavity facet of the semiconductor laser, the cavity facet is coated with an end face via an adhesion layer. A method for manufacturing a semiconductor laser, comprising: 110. A method of manufacturing a semiconductor laser using a group III-V compound semiconductor, wherein a substrate on which a semiconductor laser structure using a group III-V compound semiconductor is formed is processed into a bar shape to form a cavity end face. After that, the end face of the resonator is coated with an end face via an adhesive layer. 111. A semiconductor device having an end face formed by processing a III-V compound semiconductor, wherein an end face coat film is formed on the end face via an adhesion layer. 112. A method for manufacturing a semiconductor device having an end face formed by processing a group III-V compound semiconductor, wherein the end face is formed, and the end face is coated with an end face via an adhesion layer. A method of manufacturing a semiconductor device, comprising: 113. A semiconductor laser characterized in that an end face coating film is formed on an end face of a resonator via an adhesion layer. 114. A method of manufacturing a semiconductor laser, comprising forming an end face of a resonator and then coating the end face of the resonator via an adhesion layer. 115. A method in which a substrate on which a semiconductor laser structure is formed is processed into a bar shape to form a cavity end face, and the cavity end face is coated with an end face via an adhesion layer. A method for manufacturing a semiconductor laser. 116. A semiconductor device having an end face formed by processing a semiconductor, wherein an end face coat film is formed on the end face via an adhesion layer. 117. A method of manufacturing a semiconductor device having an end face formed by processing a semiconductor, wherein after forming the end face, the end face is coated with an end face via an adhesion layer. Semiconductor device manufacturing method.