JP2002134822A - Semiconductor light emitting device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the materials and structures of an electrode, solder, heat sink or the like which allow the formation of an efficient and reliable device wherein a semiconductor light emitting element including a nitride semiconductor layer is mounted on a GaN substrate. SOLUTION: On a face of the GaN substrate 7 opposite from one formed with nitride semiconductor laminates 101, 102, and 103, a first metal film 10 is formed of a material including A1 as an electrode. For metallization, a second metal film 11 is deposited on the lower face of the metal film 10 as a barrier layer for preventing the deterioration in ohmic contact of the electrode due to the diffusion of Au, Ni, solder or the like, and on the lower face of the second metal film 11, a third metal film 12 formed of Au, Ni, or the like is evaporated. Using the solder 13 formed of In, Sb or the like, the structure is bonded to the heat sink 14 formed of Au or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor light emitting device such as a semiconductor laser device or a semiconductor light emitting diode device in which a multilayer thin film (element structure) made of a nitride semiconductor is formed on a GaN substrate having a hexagonal crystal structure. More particularly, the present invention relates to a semiconductor light emitting device mounted (mounted) on a support base with the N-type electrode side as a bonding surface and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, nitride-based semiconductors have been receiving attention as materials for blue light-emitting devices. Heretofore, this nitride-based semiconductor has been laminated on a sapphire substrate, and at present, it has been reported that the nitride-based semiconductor has been made into a device and has a performance that can withstand practical use.

FIG. 11 is a diagram showing the structure of a semiconductor laser device disclosed in Japanese Patent Application Laid-Open No. 10-107384 regarding such a technique. In FIG. 11, reference numeral 71 denotes an oxide (sapphire) substrate; 72, a semiconductor laser main body composed of a multilayer thin film 72 of a nitride semiconductor formed on the substrate surface; and 73, 74 for supplying power to the semiconductor laser main body. 75, a heat sink (support base), 76
Is a conductive adhesive (solder) made of metal, and 77 is a metal film formed on the back surface of the oxide substrate 71.
Examples of the metal film 77 include Ti, Cr, W, Ni, Zr, which are known as metals having good adhesion to oxides.
Mo, Al, V, etc. are selected, and the film thickness is 0.1 μm or more.
0.2 μm. In this structure, since the metal film 77 having good adhesion to the oxide is formed on the back surface of the oxide substrate 71, the semiconductor laser chip and the solder are firmly bonded to each other, and the semiconductor laser chip and the support base are adhered to each other. Thermal conductivity improves.

[0004] Such a semiconductor laser device can be manufactured, for example, by the following steps. First, a multilayer thin film 72 made of a nitride-based semiconductor is formed on an oxide substrate 71 such as sapphire (surface side) by a crystal growth method, and a wafer having electrodes 73 and 74 formed on the upper surface thereof is appropriately produced. Next, the metal film 77 is formed on the back surface of the wafer.
Is formed into a thin film by a vapor deposition method or the like. Subsequently, a groove is formed at a predetermined position on the back surface of the substrate by a diamond point, and the wafer is divided along the groove to form individual laser chips (scribing method). At this time, the resonator mirror surface of the semiconductor laser chip can be formed at the same time. Thereafter, the semiconductor laser chip is soldered with a solder such as an Au-based solder that is usually used for mounting.
The semiconductor laser device is completed by die bonding on a supporting base such as a heat sink or a submount.

[0005]

However, the above-mentioned prior art has the following problems. Since the sapphire substrate is an insulator and has a feature that the cleavage surface is different from that of the nitride-based semiconductor laminated, it is difficult to form a high-quality waveguide end surface (resonator mirror surface). Further, the formation of the P-type electrode and the N-type electrode on the substrate surface complicates the device-forming process, thereby increasing the cost. Further, there is a problem that the current density in the active layer is reduced and the efficiency is reduced.

On the other hand, recently, studies have been made on using a GaN crystal, which is the same material as the nitride-based semiconductor to be laminated, as a substrate. The use of a GaN substrate solves the above-mentioned problems, but has not established a technique for mounting on a heat sink. In particular, it is expected that the heat sink also serves as a current path to the semiconductor laser chip by mounting the surface on which the N-type electrode is provided so as to be in close contact with the heat sink. It has been found that unless an appropriate structure is provided between the mold electrode and the heat sink, the characteristics of the N-type electrode deteriorate.

The present invention has been made in order to solve such problems of the prior art, and has high reliability when mounting a semiconductor light emitting device in which a nitride semiconductor is laminated on a GaN substrate. It is an object of the present invention to provide a semiconductor light emitting device capable of obtaining good characteristics and a method for manufacturing the same.

[0008]

A semiconductor light emitting device according to the present invention includes a semiconductor light emitting device having a support base and a semiconductor light emitting element mounted on the support base and provided with a nitride semiconductor laminated body on a GaN substrate. A light emitting device, comprising: a first metal that functions as an N-type electrode on a surface of the GaN substrate opposite to a surface on which the stacked body is provided, the material being made of a material capable of forming an ohmic junction with the GaN substrate. A second metal film made of a high melting point metal and functioning as a barrier layer; and a third metal film made of a material that is easily mixed with solder.
The solder is provided between the metal film and the supporting base, thereby achieving the above object.

The thickness of the second metal film is not less than 8 nm and not more than 80.
nm or less.

A semiconductor light emitting device according to the present invention is a semiconductor light emitting device having a support base and a semiconductor light emitting element mounted on the support base and provided with a nitride semiconductor laminated body on a GaN substrate. A first metal film, which is made of a material capable of forming an ohmic junction with the GaN substrate and functions as an N-type electrode, on a surface of the GaN substrate opposite to the surface on which the stacked body is provided; And a second metal film functioning as a barrier layer, comprising an alloy layer of a third metal and solder that is easily mixed with solder between the second metal film and the support base, The thickness of the second metal film is 8 nm or more and 80 nm or less, thereby achieving the above object.

The first metal film contains Al, and the second metal film includes
Contains at least one of Mo, W, Cr, Ta, Zr, and Mn, and the third metal film or the third metal contains at least one of Au and Ni. Is also good.

[0012] The crystal structure of the GaN base plate may be hexagonal, and a mounting surface on the support base may be substantially parallel to a c-plane.

The solder is made of In, Sn, Zn, Au, P
It may contain at least one of b, Ag, Cd, Bi, Ni, Mn and Cu.

[0014] The support base may be made of Si, and the third metal film or the third metal may contain at least one of Au, Ni and Al.

The supporting base is made of Si, and the solder is made of In, Sn, Zn, Au, Pb, Ag, Cd, Bi,
It may include at least one of Ni, Mn, Cu, SnCl ₂ and ZnCl ₂ .

The support base is made of Si, and Pt, Al, Ti, Cr, Co, and Pt are formed on the solder-side surface of the support base.
A metal film containing at least one of Ni, Pd, Hf, W, Mo and Ta may be provided.

[0017] The supporting base may be made of Si, and a metal film containing at least one of Au, Ni and Al may be provided on a portion of the supporting base in contact with the solder.

The light receiving element may be formed integrally with the supporting base made of Si.

A method for manufacturing a semiconductor light emitting device according to the present invention is a method for manufacturing a semiconductor light emitting device according to the present invention, wherein a wafer provided with a nitride-based semiconductor laminate on a GaN substrate is provided. Forming a first metal film, a second metal film, and a third metal film on a surface of the GaN substrate opposite to the surface on which the laminated body is provided; and forming the wafer into a semiconductor light emitting device. A dividing step and a step of bonding by heat treatment to a support base on which solder is previously laminated, or a step of laminating solder on the third metal film and bonding to the support base by heat treatment, whereby the above object is achieved. Is achieved.

A method for manufacturing a semiconductor light emitting device according to the present invention is a method for manufacturing a semiconductor light emitting device according to the present invention, wherein a wafer having a nitride semiconductor laminated body provided on a GaN substrate is provided. Forming a first metal film, a second metal film, and a third metal film on a surface of the GaN substrate opposite to the surface on which the laminated body is provided; and forming the wafer into a semiconductor light emitting device. A step of dividing, and forming and bonding an alloy layer made of the third metal and the solder by heat treatment with a support base on which solder is previously laminated, or laminating solder on the third metal film and performing heat treatment Forming an alloy layer made of the third metal and solder and bonding the alloy layer to a supporting base, thereby achieving the above object.

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

According to the present invention, a material such as Hf / Al capable of forming an ohmic junction with the GaN substrate is provided on the surface (back surface) of the GaN substrate opposite to the surface on which the laminated body is provided; A first metal film functioning as an N-type electrode;
A second metal film made of a high melting point metal such as Mo and functioning as a barrier layer, and a third metal film made of a soft material such as Au which is easily mixed with solder are laminated, and In is formed thereon.
And the like.

In this structure, a first metal film, a second metal film, and a third metal film are formed on a GaN substrate, and heat treatment is performed on a support base on which solder is previously laminated, so that the third metal film is formed. It is obtained by bonding the film side and the solder side. However,
During aging, the order of the layers is not limited by the diffusion of each metal, and an alloy layer is also formed. In addition, the third
When a thin metal film is formed, an alloy of a metal (third metal film) made of a material such as Au which is easily mixed with solder and a solder made of a material such as In is formed on the second metal film. A layer is formed.

In the present invention, the reason for forming the second metal film is as follows. The ohmic junction with the GaN substrate is obtained by a first metal film made of a material containing Al such as Hf / Al. In this layer, atoms such as Au from the third metal film and In from the solder are contained. When mixed and alloyed, deterioration of ohmic properties was observed.

Therefore, an Mo layer having an appropriate thickness is used as a second metal film, and a first metal film containing Al such as an Hf / Al layer and a third metal film (or a third metal film) such as an Au layer are used. When Mo is provided between the metal layer and the solder layer, Mo is a material having a high melting point and is therefore unlikely to diffuse, thereby preventing Au or In from forming an alloy with Hf / Al. In order to prevent the diffusion of solder or the like, the second metal film functions sufficiently as a barrier layer if the thickness of the second metal film is about 5 nm.
However, the first metal film contains Al, and the third metal film
In the case of containing u, since the reactivity between Al and Au is high, 8
If the thickness is not more than nm, peeling of the electrode frequently occurs. Preferably, the thickness of the second metal film is 15 nm or more.

GaN has a hexagonal crystal structure, and a plane parallel to the c-plane is used as a mount plane. Al and Au have a high linear thermal expansion coefficient with respect to the linear expansion coefficient of this plane. Further, since the supporting base made of Cu or the like also has a high linear expansion coefficient, the element is greatly deteriorated due to the influence of the strain applied to the element when the element is continuously driven for a long time. This is considered to be due to the fact that defects and the like in the crystal multiply and the luminous efficiency and the like deteriorate. Furthermore, if the second metal film is thick, the first metal film and the second metal film, and the second metal film and the third metal film become less familiar with heat treatment such as annealing or continuous driving for a long time. ,
Problems such as peeling of electrodes and electrical characteristics occur.

Therefore, an Mo layer having an appropriate thickness is used as a second metal film, and a first metal film containing Al such as an Hf / Al layer and a third metal film (or a third metal film) such as an Au layer are used. Provided between the support and the solder, the second metal film having a coefficient of linear thermal expansion relatively close to that of GaN, such as Mo, reduces distortion between the support base and the nitride-based compound semiconductor layer. As a result, the life of the device can be extended.

As a material of such a second metal film,
It is desirable that the coefficient of linear thermal expansion be substantially equal to that of the GaN substrate. For example, a material containing at least one of Mo, W, Cr, Ta, Zr and Mn can be used. The thickness of the second metal film is 8 nm or more and 80 nm or more.
The thickness is desirably not more than 8 nm, more desirably 8 nm or more and 50 nm or less.

In the present invention, the reason for providing the third metal film is as follows. Since GaN has a larger elastic constant than GaAs or the like, cracks and the like are likely to occur when stress such as thermal expansion is applied due to aging or the like. In addition, since GaN has a hexagonal crystal structure compared to GaAs or the like having a cubic crystal structure, it is necessary to divide the wafer into planes other than the cleavage interface in order to divide the wafer into rectangles. It is easy to crack diagonally.

Thus, by adhering a soft metal such as Au to the back surface of the substrate with good adhesion, it is possible to prevent such cracks from entering, and even if a crack occurs, the crack is used as a starting point. The effect of preventing the metal film from being peeled off can be obtained. Such materials include:
For example, when the supporting base is a heat sink or the like, a material containing at least one of Au and Ni can be used. When the supporting base is a Si substrate, a substrate containing at least one of Au, Ni and Al can be used.

In the present specification, the term “solder” refers to a metal having a melting temperature of 450 ° C. or lower used for joining electronic devices. Examples of such a material include In, Sn, Zn, and
Au, Pb, Ag, Cd, Bi, Ni, Mn and Cu
A material containing at least one of the above can be used. When the supporting base is a Si substrate, I
n, Sn, Zn, Au, Pb, Ag, Cd, Bi, N
A material containing at least one of i, Mn, Cu, SnCl ₂ and ZnCl ₂ can be used.

Further, in this specification, the heat sink as the support base may include a stem, and a Si substrate may be used as the support base instead of the heat sink.
In this case, a device such as a light receiving element can be formed. When a Si substrate is used as the supporting base, as described in a fifth embodiment described later, Pt, Al, and Pt are formed on the solder-side surface of the Si substrate as materials having high adhesion to the Si substrate and capable of forming an ohmic junction. Ti, Cr, Co, Ni,
It is preferable to provide a metal film containing at least one of Pd, W, Mo, Ta and Hf. Further, a metal silicide such as PtSi may be provided between the Si substrate and the metal film. Furthermore, Mo, Cr,
By providing a metal film containing at least one of W, Ti, Ta, Pt, and Pd, the metal film can function as a barrier layer. Further, by providing a metal film containing at least one of Au, Ni, and Al on a portion of the support base that is in contact with the solder, a strong bond between the Si substrate and the semiconductor light emitting element can be obtained.

[0033]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
FIG. 3 is a schematic diagram of the semiconductor laser device of FIG. 1, showing a state in which an N-type electrode (first metal film) is formed on the stacked body of the GaN substrate and the nitride-based semiconductor shown in FIG. 2 and mounted on a heat sink (such as a stem). ing.

In the semiconductor laser chip 300, a first metal film 10, a second metal film (diffusion preventing barrier layer) 11, a third metal film 12, and a solder 13 are laminated on a back surface of a GaN substrate 7. 14 mounted.

FIG. 2 is a schematic view of the semiconductor laser according to the first embodiment as viewed from an end face, and shows a state before an N-type electrode is provided and a semiconductor laser chip is formed. In FIG. 2, a part (semiconductor laser structure) of the semiconductor laser chip 300 shown in FIG. 1 is enlarged.

In this figure, 7 is a GaN substrate,
The nitride semiconductor laminates 101, 102, 10
3 are formed. Also, a nitride semiconductor laminate 1
A P-type electrode 100 is provided on the surface of the reference numeral 01. The nitride semiconductor laminates 101, 102 and 103 are made of GaN
From the substrate 7 side, the n-InAlGaN cladding layer 6, n-
InAlGaN guide layer 5, InAlGaN multiple quantum well active layer 102, p-InAlGaN barrier layer 4, p-
An InAlGaN guide layer 3, a p-InAlGaN cladding layer 2, and a p-InAlGaN contact layer 1 are stacked in this order.

The method of manufacturing the semiconductor laser device according to the first embodiment will be described below with reference to FIGS.

First, a semiconductor laser wafer having a number of individual semiconductor laser structures shown in FIG. 2 formed on a GaN substrate 7 was obtained by appropriately using a process used for manufacturing a semiconductor device. Since the process of obtaining such a wafer is a well-known technique, a detailed description is omitted. In the present embodiment, the thickness of the GaN substrate was 350 μm, and the total thickness of the nitride semiconductor laminate was 10 μm.

Next, a part of the GaN substrate is removed by polishing or etching from the back side of the GaN substrate, and the thickness of the wafer is adjusted to be thin to about 100 μm to 200 μm.
This is a process for making it easier to divide the wafer into individual semiconductor laser chips in a later process. In particular, when the laser end face mirror is also formed at the time of division, it is desirable to adjust the thickness of the wafer to be as thin as about 80 μm to 50 μm. In the present embodiment, the thickness of the wafer was adjusted to 100 μm using a grinding machine and a polishing machine. However, only a polishing machine may be used. The back surface of the wafer thus obtained is flat because it has been polished by a polishing machine, and is substantially parallel to the c-plane of GaN, which is hexagonal.

Next, a first metal film 10, a second metal film 11, and a third metal film 12 are formed in this order on the back side of the GaN substrate. Here, the first metal film 10 which is an N-type electrode
Need to take ohmic junction with the GaN substrate 7.
Further, the third metal film 12 must be made of a metal that is soft to prevent cracks when dividing the semiconductor laser chip and that is easily mixed with solder when the semiconductor laser chip is mounted on a heat sink. is there.
Further, it is necessary to select a high melting point metal for the second metal film 11 in order to prevent the metal and the solder constituting the third metal film 12 from diffusing and deteriorating the characteristics of the N-type electrode. In the first embodiment, a 100 nm Hf / Al layer is laminated as the first metal film 10, and the second metal film 1
As 1, a 30 nm-thick Mo layer was stacked, and as the third metal film 12, a 300 nm-thick Au layer was stacked. In order to form such a thin metal film with good controllability of the film thickness, a vacuum evaporation method is suitable, and this method is also used in the first embodiment. However, it goes without saying that another method such as an ion plating method or a sputtering method may be used. Further, in order to improve the N-type electrode characteristics, annealing was performed at 500 ° C. after the formation of the third metal film 12. There is no problem if this annealing is performed after the formation of the first metal film (N-type electrode) 10 or after the formation of the second metal film 11.

Thereafter, the wafer was divided into individual semiconductor laser chips in a chip dividing step. The split direction is
It is almost perpendicular to the cleavage interface. First, a scribe line was formed at the diamond point from the back surface, and the wafer was divided along the scribe line by appropriately applying a force to the wafer. This scribe line may be inserted from the surface. As other methods, a dicing method for making a cut or cut using a wire saw or a thin plate blade, a laser beam irradiation heating such as an excimer laser or the like and a subsequent quenching cause a crack to be generated in an irradiated portion, and this is used as a scribe line. Similarly, chip division can be performed by using a laser scribing method, a laser ablation method of irradiating a laser beam having a high energy density and evaporating this portion to perform grooving. As a result, a laser structure as shown in FIG. 2 was obtained.

Next, the semiconductor laser chip was mounted on a heat sink by a die bonding method. This step was performed as follows. First, as shown in FIG.
Solder 13 was applied to heat sink 14. In the first embodiment, the heat sink 14 is made of a metal mainly composed of Cu or Fe, and has Ni / Au
A film obtained by plating a film in order was used. In was used for the solder 13, and the thickness after the application was about 1 μm to 20 μm. As described above, the solder 13 may be formed into a film by coating in advance, or may be formed by using another film forming method such as an evaporation method, a sputtering method, a printing method, or a plating method. However, when the solder is particularly soft at room temperature, as in the case of solder mainly composed of In or Sn, it is preferable to use a coating method with extremely high productivity. Next, the heat sink 14 is heated to a temperature slightly higher than the melting point of the solder at about 190 ° C., and when the solder is melted, the laser chip obtained as described above is stacked with the N-type electrode side down, The third metal film 12 and the solder 13 were well blended with each other for about one minute while appropriately applying force. Then, the heat sink 14 is cooled and the solder 1
This process was completed when 3 was solidified. in this way,
When the third metal film, the solder, and the heat sink are brought into close contact with each other and heated, the solder diffuses into the third metal film and the heat sink, and is firmly bonded by alloying.
Here, when the third metal film is thick, the region where the solder is not diffused remains as the third metal film, and the region between the third metal film (the region where the solder is not diffused) and the third metal and the solder is formed. An alloy layer (shown as solder 13 in FIG. 1) is formed. When the third metal film is thin, all of the solder diffuses, and only an alloy layer 22 of the third metal and the solder is formed as described in a second embodiment described later. In the present embodiment, the thickness of the third metal film is the remaining layer thickness of the third metal after bonding.

Although the solder 13 is applied to the heat sink 14 before this step, the solder 13 may be applied to the semiconductor laser chip or a film may be formed. Thus, the semiconductor laser device of the first embodiment shown in FIG. 1 was obtained.

The characteristics of the semiconductor laser chip mounted on the heat sink by the above steps were evaluated. The present invention is intended to obtain a semiconductor laser device having excellent life characteristics, and for that purpose, it is necessary to make the N-type electrode characteristics robust and excellent in thermal resistance without deteriorating the characteristics. As a result of examining the semiconductor laser device of the first embodiment, good characteristics were obtained. At that time, for comparison, the following experiment was performed under different conditions.

First, in order to investigate the effect of the barrier layer as the second metal film, a high temperature (60
C.) and the oscillation threshold characteristics at room temperature (20 ° C.) (FIG. 4). The experimental conditions were
4. At room temperature (20 ° C.)
The average data of 50 devices mounted on a 6φ stem was totaled. The conditions of the metal film other than the barrier layer were fixed at the values described above.

The oscillation threshold value was determined from the result by measuring the current versus light output characteristics by applying a direct current to the automatic measuring instrument at room temperature (20 ° C.). In addition, the life characteristics are determined by using an aging device and oscillating under the condition that the light output is constant (5 mW) in a chamber where the ambient temperature is constant (60 ° C.), and is stable after initial deterioration (rapid deterioration). Was observed for its lifetime.

As a result of this measurement, as shown in FIGS. 3 and 4, the thickness of the barrier layer affects various characteristics, and almost good results are obtained in the range of 8 nm to 80 nm.

When the barrier layer was removed, continuous oscillation at room temperature stopped. When the characteristics of the N-type electrode were examined, no ohmic junction was obtained. This is because Au (third metal film 12) and In (solder 13) penetrate into the Hf / Al layer (first metal film 10), and in the presence of GaN, Al, Au, In, all or GaN substrate 7 containing several alloys
It is considered that the film was formed on the surface of the. Also, Al,
The bonding of Au was weak, and electrode failure occurred frequently.

When the barrier layer is thinned (<8 nm), the life is shortened. Such a thin Mo layer (second layer)
In the metal film 11), Au and In are not enough to prevent diffusion of Au and In, and Au and In penetrate the Hf / Al layer through the Mo layer during aging, and GaN, Al, Au,
It is considered that, in the presence of In, an alloy containing all or some of these was formed on the surface of the GaN substrate 7, so that the electrode characteristics were deteriorated. In addition, the peeling of the metal film also increased. This is because the reaction between Au and Al that has passed through the Mo layer causes peeling from the Au layer, and the peeling of the Au layer easily causes cracks in the GaN substrate, thereby causing peeling of the metal film starting therefrom. It is.

It has been found that when a barrier layer having an appropriate thickness is provided, device deterioration is reduced in continuous driving for an extremely long time. GaN is hexagonal, and a plane parallel to the c-plane is used for the mounting surface, and Al and Au have a higher linear thermal expansion coefficient than the linear expansion coefficient of this plane. Further, since the supporting base made of Cu or the like also has a high linear expansion coefficient, the element is greatly deteriorated due to the influence of the strain applied to the element when the element is continuously driven for a long time. This is considered to be due to the fact that defects and the like in the crystal multiply and the luminous efficiency and the like deteriorate.

Therefore, when a Mo layer or the like having an appropriate thickness is provided as a barrier layer (second metal film), the second metal film such as Mo, which has a linear thermal expansion coefficient relatively close to that of GaN, is formed on the supporting base by nitriding. Strain with the compound semiconductor layer can be reduced, and the life of the device can be extended.

However, when the barrier layer is thickened (> 80 n
m), the service life is shortened, and the oscillation threshold is increased. This is because if the second metal film is thick, the first metal film and the second metal film, and the second metal film and the third metal film become less familiar with heat treatment such as annealing or continuous driving for a long time. It is thought to be.

As a result, when a semiconductor laser chip using a GaN substrate is mounted on a heat sink with the N-type electrode side as a mounting surface, a diffusion preventing barrier having an appropriate thickness is used as a metal film on the back surface of the GaN substrate. Layer (second
Metal film) is required, and its film thickness is 8 nm to 80 nm.
It turned out to be good. Further, when the metal material of the barrier layer was examined, it was found that Cr, W, Zr and Ta, which are high melting point metals and have a linear thermal expansion coefficient in a direction parallel to the c-plane of the GaN substrate and a linear thermal expansion coefficient substantially similar to each other. Has a similar effect,
It has been found that the material of the second metal film may be Mo, Cr, W, Zr or Ta alone or a mixture containing at least one of them. In the case of Pt, which has a relatively high melting point, a high oscillation threshold value and a short life are obtained, and defects due to peeling of the metal film frequently occur. this is,
Since the adhesion of the Pt to the Al layer is poor due to the property of easily adsorbing Pt, the electrode characteristics are deteriorated, and the linear thermal expansion coefficient of Pt is larger than that of Mo, Cr, W, Zr or Ta. It is considered that the cause is that the adhesion between the film and the GaN substrate is deteriorated.

Next, the change when the thickness of the Au layer as the third metal film was changed was examined as follows.

First, a semiconductor laser device was manufactured in the same manner as in the first embodiment except that the thickness was set to 5 nm using Au as the third metal film. As a result, mounting failures occurred frequently. When the N-type electrode side surface of the peeled semiconductor laser chip was observed, almost no Au remained on the Mo surface, and Au as the third metal film was solder In.
It can be seen that the reaction with the second metal film was almost completed, and the bonding with the second metal film was weakened.

Next, a semiconductor laser device was manufactured in the same manner as in the first embodiment except that the thickness was set to 50 μm using Au as the third metal film. As a result, when a scribe line was formed at the diamond point from the back surface in the laser chip dividing process, peeling or sagging of Au was induced, and defective chips occurred frequently.

From the above results, the third metal film has a thickness of 50
It has been found preferable to use Au having a thickness of about 10 nm to about 10 nm. However, the material is not limited to Au alone, but may be Ni or Au.
Any alloy containing, for example, AuNi or AuPt was found to be usable.

It is known that the first metal film may be a material having good adhesion to the GaN substrate and capable of ohmic bonding. It mainly consists of a layer containing Al, Ti,
Any material containing a material selected from Zr and Hf may be used. Further, it was found that the thickness of the electrode should be about 10 nm to 1 μm.

Next, the material of the solder was examined. What is required for the solder is to select a material having high adhesion to the third metal film and the heat sink in order to keep the thermal resistance of the semiconductor laser device low. Since the third metal film and the heat sink (the surface thereof) are mainly composed of Au, solder having high adhesion to Au may be used. In addition to In used in the first embodiment, S
n, Zn, Au, Pb, Ag, Cd, Bi, Ni, Mn
Etc. showed good results. Further, an alloy containing the above solder as a main component may be used.

(Embodiment 2) FIG. 5 shows Embodiment 2 of the present invention.
FIG. 7 is a schematic view of the semiconductor laser device in FIG. 6, in which a first metal film (N-type electrode) is formed on the stacked body of the GaN substrate and the nitride-based semiconductor shown in FIG.
It shows the state mounted on.

The semiconductor laser chip 303 is mounted on a back surface of the GaN substrate 7 and mounted on a heat sink (such as a stem). On the back surface of the GaN substrate 7, a first metal film 20, a second metal film (diffusion prevention barrier layer) 21,
An alloy layer 22 of a third metal and solder is laminated and mounted on a heat sink 23.

FIG. 6 is a schematic view of the semiconductor laser according to the second embodiment as viewed from an end face, and shows a state before an N-type electrode is provided to form a semiconductor laser chip. In FIG. 6, a part (semiconductor laser structure) of the semiconductor laser chip 303 shown in FIG. 5 is enlarged.

In this figure, 7 is a GaN substrate,
The nitride-based semiconductor laminates 201, 202, 20
3 are formed. Also, a nitride semiconductor laminate 2
A P-type electrode 200 is provided on the surface of the reference numeral 01. The nitride semiconductor laminates 201, 202, and 203 are made of GaN
From the substrate 7 side, an n-InAlGaN cladding layer 209,
n-InAlGaN guide layer 208, InGaNAsP
Multiple quantum well active layer 202, p-InAlGaN barrier layer 207, p-InAlGaN guide layer 206, p-I
An nAlGaN cladding layer 205 and a p-InAlGaN contact layer 204 are stacked in this order.

A method of manufacturing the semiconductor laser device according to the second embodiment will be described below with reference to FIGS.

The main manufacturing method is the same as in the first embodiment. First, the nitride semiconductor-based laminates 201, 202, and 203 are formed by the method described in Embodiment 1 using a process used for manufacturing a semiconductor element as appropriate.
A metal film is laminated on the back surface of the GaN substrate 7 polished to about 100 μm by the method described in the first embodiment.

Next, a first metal film 20, a second metal film 21, and a third metal film are formed in this order on the back surface side of the GaN substrate. Here, the first metal film 20, which is an N-type electrode,
It is necessary to take ohmic junction with the GaN substrate 7. Further, as the third metal film, it is necessary to select a metal that is easily mixed with solder when the semiconductor laser chip is mounted on the heat sink. Further, it is necessary to select a metal having a high melting point for the second metal film 21 in order to prevent the third metal and the solder from being diffused and deteriorating the characteristics of the N-type electrode. In the second embodiment, a 100 nm Ti / Al layer is laminated as the first metal film 20, a 30 nm thick W layer is laminated as the second metal film 21, and a third metal film is formed. An Au layer having a thickness of 200 nm was laminated. Furthermore, in order to improve the N-type electrode characteristics, after forming the third metal film,
Annealing was performed at 500 ° C. There is no problem if this annealing is performed after forming the first metal film (N-type electrode) 20 or after forming the second metal film 21.

Thereafter, the wafer was divided into semiconductor laser chips by the method described in Embodiment 1, and the semiconductor laser chips were mounted on a heat sink by die bonding. This step was performed as follows. First, solder was applied on the third metal film. In the present embodiment, AuSn is used for the solder, and the thickness after coating is about 1 μm to 20 μm. The solder may be formed into a film by coating in advance as described above, or may be formed using another film forming method such as a vapor deposition method, a sputtering method, a printing method, or a plating method. However, when the solder is particularly soft at room temperature, as in the case of solder mainly composed of In or Sn, it is preferable to use a coating method with extremely high productivity. Next, the heat sink 23 is
The solder is heated to a temperature slightly higher than the melting point of the solder at about 0 ° C., and when the solder is melted, the laser chip obtained as described above is mounted with the N-type electrode side down, and 1 After holding for about a minute, the third metal film and the solder were well blended. Thereafter, when the heat sink 23 was cooled and the solder was solidified, the present process was terminated. In addition,
Here, solder was applied to the semiconductor laser chip side before this process, but on the contrary, solder was applied to the heat sink side,
A film may be formed.

In this step, the third metal film and the solder are sufficiently adapted to each other, and an alloy layer 22 of the third metal film and the solder is formed. Thus, the semiconductor laser device of the second embodiment shown in FIG. 5 is obtained. Was done.

When the characteristics of the semiconductor laser chip mounted by the above steps were evaluated in the same manner as in the first embodiment, the thickness of the W layer as the second metal film was 8n.
In the case of m to 80 nm, both the lifetime and the threshold characteristics showed good values.

As a result, when a semiconductor laser chip using a GaN substrate is mounted on a heat sink with the N-type electrode side as a mounting surface, a diffusion preventing barrier having an appropriate thickness is used as a metal film on the back surface of the GaN substrate. Layer (second
Metal film) is required, and the film thickness is 8 nm to 80 μm
It turned out to be good. Further, when the metal material of the barrier layer was examined, it was found that Cr, Mo, Zr
And Ta also show the same effect, and the material of the second metal film is Mo,
It turned out that Cr, W, Zr or Ta alone or a mixture containing at least one of them may be used. In the case of Pt, which has a relatively high melting point, a high oscillation threshold value and a short life are obtained, and defects due to peeling of the metal film frequently occur. This is because Pt easily adheres to the gas due to the property of easily adsorbing gas, and the electrode characteristics are deteriorated, and the linear thermal expansion coefficient of Pt is Mo, Cr, W, Zr.
This is considered to be caused by the fact that the adhesion between the metal film and the GaN substrate is deteriorated due to being larger than that of Ta or Ta.

Next, the change when the thickness of the Au layer as the third metal film was changed was examined.
It has been found that it is preferable to use Au of about 10 μm. However, the material is not limited to Au alone, but may be any alloy containing Ni or Au. For example, it has been found that AuNi, AuPt, or the like can be used.

It is known that the first metal film may be any material that has good adhesion to the GaN substrate and can be ohmic-joined. It mainly consists of a layer containing Al, Ti,
Any material containing a material selected from Zr and Hf may be used. Further, it was found that the thickness of the electrode should be about 10 nm to 1 μm.

Next, the material of the solder was examined. What is required for the solder is to select a material having high adhesion to the third metal film and the heat sink in order to keep the thermal resistance of the semiconductor laser device low. Since the third metal film and the heat sink (the surface thereof) are mainly composed of Au, a solder having high adhesion to Au may be used. In addition to AuSn used in the second embodiment,
Zn, Pb, Ag, Cd, Bi, Ni, Mn, In, S
n, Au, etc. showed good results. Further, an alloy containing the above solder as a main component may be used.

(Embodiment 3) FIG. 7 shows Embodiment 3 of the present invention.
FIG. 2 is a schematic diagram of a semiconductor laser device in FIG. The third embodiment is different from the first and second embodiments in the first embodiment.
In this case, the shapes of the metal film and the second metal film are changed.

As shown in FIG. 7, a first metal film 30 is provided on the back surface of the GaN substrate 7, and a second metal film 31 is laminated on the lower surface of the first metal film 30. The first metal film 30 has a stripe shape with a width of 50 μm and a thickness of 100 nm. Similarly, the second metal film 31 also has a stripe shape with a width of 50 μm and a thickness of 30 nm. The third metal film 32 is made of a metal containing Au, and has a thickness of 1 μm. A solder 33 (on which a third metal film and an alloy layer of solder are formed as in the first embodiment) is formed thereon, and the semiconductor laser chip 301 is mounted on the heat sink 14. Or, Embodiment 2
As described above, an alloy layer of a third metal film and solder may be formed.

An experiment was conducted on the characteristics of this semiconductor laser device, and as a result, the electric resistance and the thermal resistance showed almost the same values as in the first embodiment. Further, when the third embodiment is used, the end face formation and the chip division are facilitated, and the yield is improved. This is presumably because when the scribe line is formed, the metal film laminated at that location is thin.

In the structure of the third embodiment, the Al layer (the first metal film) and the Au layer (the third metal film) are partially in contact with each other, and GaN, Al, A
An alloy such as u, In or the like may be formed, and the electrode characteristics may be deteriorated. However, with respect to an electrode having a width of 50 μm, such a portion was about 0.2 μm or less on both sides of the electrode, and no problem occurred.

The first metal film and the second metal film are manufactured so that the stripe position is above the laser waveguide and the stripe position is shifted from above the laser waveguide. When made in the same way as above, no significant changes were seen. This is presumably because electrons supplied from the N-type electrode are diffused in the GaN substrate, so that there is no problem in current injection even if the electrons are shifted from the laser stripe.

Further, the thickness of the third metal film is set to 200 nm.
And the other method was the same as that of the third embodiment, a semiconductor laser chip with poor flatness on the surface of the third metal, frequent mounting failures, and high thermal resistance was observed. . From the above results, it is understood that the thickness of the third metal film needs to be larger than at least the sum of the thicknesses of the first metal film and the second metal film.

As a result, in the third embodiment, the first metal film and the second metal film are not limited to any particular shapes.
It has been found that each film thickness may be in accordance with the first embodiment. Further, it was found that the thickness of the third metal film may be the same as that of Embodiment 1 except that the thickness is larger than the sum of the thicknesses of the first metal film and the second metal film.

(Embodiment 4) FIG. 8 shows Embodiment 4 of the present invention.
FIG. 2 is a schematic diagram of a semiconductor laser device in FIG. The fourth embodiment is different from the first and second embodiments in the first embodiment.
Is a modification of the shape of the metal film.

As shown in FIG. 8, a first metal film 40 is provided on the back surface of the GaN substrate 7, and a second metal film 41 is laminated on the lower surface of the first metal film 40. The first metal film 40 has a stripe shape with a width of 50 μm and a thickness of 100 nm. The thickness of the second metal film 41 is 15
0 nm. The third metal film 42 is made of a metal containing Au and has a thickness of 1 μm. A solder 43 (an alloy layer of a third metal and a solder is formed as in the first embodiment) is formed thereon, and the semiconductor laser chip 302 is mounted on the heat sink 14. Alternatively, as in Embodiment 2, an alloy layer of a third metal and solder may be formed.

As a result of conducting an experiment on the characteristics of this semiconductor laser device, both the electric resistance and the thermal resistance showed almost the same values as in the first embodiment. Further, similarly to the third embodiment, the end face formation and the chip division were facilitated, and the yield was improved.

The first metal film and the second metal film are manufactured so that the stripe position is above the laser waveguide and the stripe position is shifted from above the laser waveguide. When made in the same way as above, no significant changes were seen.

Further, when the film thickness of the second metal film was set to 10 nm, and the others were manufactured in the same manner as in the fourth embodiment, deterioration of the electric resistance was observed. This is because the thickness of the second metal film becomes thinner at the corners of the first metal film, and A
It is considered that u diffused. From the above results, the second
It can be seen that the thickness of the metal film needs to be at least larger than that of the first metal film.

As a result, it has been found that, in the fourth embodiment, the first metal film (N-type electrode) is not limited to a particular shape, and its thickness may be in accordance with the first embodiment. Further, it was found that the thickness of the second metal film may be the same as that of Embodiment 1 except that the thickness of the second metal film is larger than the thickness of the second metal film.

(Embodiment 5) FIG. 9 shows Embodiment 5 of the present invention.
FIG. 2 is a schematic diagram of a semiconductor laser device in FIG. In the fifth embodiment, the stacked structure of the nitride-based semiconductor and the first metal film, the second metal film, and the third metal film manufactured on the GaN substrate are the same as those described in the first to fourth embodiments. Any of them may be used.

The semiconductor laser chip 406 is mounted on a Si substrate 401 instead of a heat sink, and a device such as a light receiving element 402 may be formed on the Si substrate 401. In FIG. 9, reference numeral 403 denotes an electrode, 404 denotes a wire bond, 405 denotes a solder, and 407 denotes a wire bond.

A structure 500 as shown in FIG. 10 is formed on the Si substrate side for bonding with a semiconductor laser chip. Si
A fourth metal film 51 is formed on the substrate 50, a fifth metal film 52 is stacked as a barrier layer on the upper surface of the fourth metal film 51, and solder and a solder are formed on the upper surface of the fifth metal film. A sixth metal film 53 is laminated to increase the adhesion of the metal.

The fourth metal film is required to have high adhesion to the Si substrate and to form an ohmic junction. Further, the fifth metal film is formed by diffusing the sixth metal and the solder to form the fourth metal film.
In order to prevent the electrode characteristics of the metal film from deteriorating, it is necessary to select a metal having a high melting point. Although several materials are known as such metals, the fifth embodiment
In the above, 170n of Pt / Ti is used as the fourth metal film.
m. After laminating the fourth metal film, an ohmic electrode can be obtained by heating at an appropriate temperature. At this time, PtSi which is a metal silicide may be formed at the interface between the Si substrate and the fourth metal film.

For the fifth metal film, Mo is 100 nm, and the sixth metal film is
The sixth metal film in which Au is laminated on the metal film of 1 μm is the same material as the third metal film for strong bonding between the semiconductor laser chip and the Si substrate.

The method of depositing Pt / Ti used for the fourth metal film is the same as the method of depositing a metal film on a GaN substrate in the first embodiment. Next, after the fifth and sixth metal films are deposited, the semiconductor laser chip is mounted on the Si substrate manufactured by the above-described process in the same manner as in the first embodiment.
Thus, the semiconductor laser device of the fifth embodiment shown in FIG. 9 was obtained.

Next, various metal materials were examined. As a fourth metal film, Pt, Ti, Mo, W, Cr, C
It has been found that o, Ni, Pd, Hf, Al or Ta alone or a mixture containing at least one of them may be used, and the thickness is preferably 10 nm to 1 μm.

As the fifth metal film, Mo, Cr, W,
A simple substance of Ti or Ta or a mixture containing at least one of them may be used. Further, even if the fourth metal film is single or multilayer, if the surface is not Al, as the fifth metal film, a single metal of Pt or Pd or Mo, W, Cr, Ti, Ta, Pt, Pd Among them, a mixture containing at least one of them may be used. Fifth
When the thickness of the metal film was 5 nm to 500 nm, good results were obtained.

The sixth metal film may be made of the same material as the third metal film, and is preferably Au or Ni alone, or a mixture containing any one of them, or Al alone.
Good results were shown if the thickness was 50 nm to 10 μm. Note that it is necessary to use a simple substance of Al as the third metal film only when the simple substance of Al is used as the sixth metal film. In the case where the sixth metal film is not Al alone, the same material as in the first embodiment can be used.

Here, along with the selection of the sixth metal film, the following material for the semiconductor laser chip was examined. (2nd metal film, 3rd and 6th metal film, solder) = (Mo, Au, In), (Mo, Au, Sn), (Mo, Au, Zn), (Mo, Au, Au) , (Mo, Au, Pb), (Mo, Au, Ag), (Mo, Au, Cd), (Mo, Au, Bi), (Mo, Au, Cu), (Mo, Au, Ni), ( Mo, Au, Mn), (W, Au, In), (W, Au, Sn), (W, Au, Zn), (W, Au, Au), (W, Au, Pb), (W, Au, Ag), (W, Au, Cd), (W, Au, Bi), (W, Au, Cu), (W, Au, Ni), (W, Au, Mn), (Mn, Au, In), (Mn, Au, Sn), (Mn, Au, Zn), (Mn, Au, Au), (Mn, Au, Pb), (Mn, Au, Ag), (Mn, Au, C) d), (Mn, Au, Bi), (Mn, Au, Cu), (Mn, Au, Ni), (Mn, Au, Mn), (Cr, Au, In), (Cr, Au, Sn) , (Cr, Au, Zn), (Cr, Au, Au), (Cr, Au, Pb), (Cr, Au, Ag), (Cr, Au, Cd), (Cr, Au, Bi), ( (Cr, Au, Cu), (Cr, Au, Ni), (Cr, Au, Mn), (Zr, Au, Sn), (Zr, Au, Sn), (Zr, Au, Zn), (Zr, Au, Au), (Zr, Au, Pb), (Zr, Au, Ag), (Zr, Au, Cd), (Zr, Au, Bi), (Zr, Au, Cu), (Zr, Au, Ni), (Zr, Au, Mn), (Ta, Au, In), (Ta, Au, Sn), (Ta, Au, Zn), (Ta, Au, A u), (Ta, Au, Pb), (Ta, Au, Ag), (Ta, Au, Cd), (Ta, Au, Bi), (Ta, Au, Cu), (Ta, Au, Ni) , (Ta, Au, Mn), (Mo, Ni, In), (Mo, Ni, Sn), (Mo, Ni, Zn), (Mo, Ni, Au), (Mo, Ni, Pb), ( (Mo, Ni, Ag), (Mo, Ni, Cd), (Mo, Ni, Bi), (Mo, Ni, Cu), (Mo, Ni, Ni), (Mo, Ni, Mn), (W, (Ni, In), (W, Ni, Sn), (W, Ni, Zn), (W, Ni, Au), (W, Ni, Pb), (W, Ni, Ag), (W, Ni, Cd), (W, Ni, Bi), (W, Ni, Cu), (W, Ni, Ni), (W, Ni, Mn), (Mn, Ni, In), (Mn, Ni, S) n), (Mn, Ni, Zn), (Mn, Ni, Au), (Mn, Ni, Pb), (Mn, Ni, Ag), (Mn, Ni, Cd), (Mn, Ni, Bi) , (Mn, Ni, Cu), (Mn, Ni, Ni), (Mn, Ni, Mn), (Cr, Ni, In), (Cr, Ni, Sn), (Cr, Ni, Zn), ( (Cr, Ni, Au), (Cr, Ni, Pb), (Cr, Ni, Ag), (Cr, Ni, Cd), (Cr, Ni, Bi), (Cr, Ni, Cu), (Cr, Ni, Ni), (Cr, Ni, Mn), (Zr, Ni, In), (Zr, Ni, Sn), (Zr, Ni, Zn), (Zr, Ni, Au), (Zr, Ni, Pb), (Zr, Ni, Ag), (Zr, Ni, Cd), (Zr, Ni, Bi), (Zr, Ni, Cu), (Zr, Ni, N i), (Zr, Ni, Mn), (Ta, Ni, In), (Ta, Ni, Sn), (Ta, Ni, Zn), (Ta, Ni, Au), (Ta, Ni, Pb) , (Ta, Ni, Ag), (Ta, Ni, Cd), (Ta, Ni, Bi), (Ta, Ni, Cu), (Ta, Ni, Ni), (Ta, Ni, Mn), ( Mo, Al, SnCl ₂ ), (Mo, Al, ZnCl ₂ ), (W, Al, SnCl ₂ ), (W, Al, ZnCl ₂ ), (Mn, Al, SnCl ₂ ), (Mn, Al, ZnCl ₂ ) ₂ ), (Cr, Al, SnCl ₂ ), (Cr, Al, ZnCl ₂ ), (Zr, Al, SnCl ₂ ), (Zr, Al, ZnCl ₂ ), (Ta, Al, SnCl ₂ ), (Ta , Al, ZnCl ₂₎ as a material of the first metal film, the same as in embodiment 1 It was used. The above-described materials were used as the materials of the fourth metal film and the fifth metal film.

As a result, good thermal resistance characteristics and good electric resistance characteristics were obtained in all combinations. Note that, in the above combination, solder represents a main component included.

In the fifth embodiment, devices such as a light receiving element and a pixel mirror may be formed on the Si substrate.
Diversification of applied products due to compactness is expected.

In the above embodiments, the semiconductor light emitting device of the present invention has been described by taking a semiconductor laser device as an example. However, as apparent from the gist of the present invention, the present invention is applicable to a semiconductor light emitting diode device. Is also possible. G
Regarding the nitride semiconductor layer laminated on the aN substrate,
In particular, the present invention is applicable to any structure and material.

[0101]

As described in detail above, according to the present invention,
The first metal film makes good ohmic contact with the GaN substrate, and the second metal film prevents the third metal film or solder from diffusing into the first metal film to form an alloy. The third metal film can prevent the substrate from cracking or peeling off the metal film. Therefore, without deteriorating thermal resistance and electric resistance, Ga
A semiconductor light emitting device in which an N substrate is mounted on a heat sink can be provided. Further, by providing the seventh metal film on the Si substrate, it is possible to provide a semiconductor light emitting device in which the GaN substrate is mounted on the Si substrate without deteriorating thermal resistance and electric resistance.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a semiconductor laser device according to a first embodiment;

FIG. 2 is a diagram illustrating a part of the semiconductor laser chip according to the first embodiment;

FIG. 3 is a graph showing life characteristics when a thickness x of a second metal film (barrier layer) is changed.

FIG. 4 is a diagram showing oscillation threshold characteristics when a second metal film (barrier layer) thickness x is changed.

FIG. 5 is a diagram showing a semiconductor laser device according to a second embodiment.

FIG. 6 is a diagram showing a part of a semiconductor laser chip according to a second embodiment.

FIG. 7 is a diagram illustrating a semiconductor laser device according to a third embodiment;

FIG. 8 is a diagram showing a semiconductor laser device according to a fourth embodiment.

FIG. 9 is a diagram showing a semiconductor laser device according to a fifth embodiment.

FIG. 10 shows S in the semiconductor laser device of the fifth embodiment.
It is a figure showing an i substrate.

FIG. 11 is a view showing a conventional semiconductor laser device.

[Explanation of symbols]

Reference Signs List 1 p-InAlGaN contact layer 2 p-InAlGaN cladding layer 3 p-InAlGaN guide layer 4 p-InAlGaN barrier layer 5 n-InAlGaN guide layer 6 n-InAlGaN cladding layer 7 GaN substrate 10 first metal film 11 second metal Film 12 third metal film 13 solder 14 heat sink 20 first metal film 21 second metal film 22 alloy layer of third metal and solder 23 heat sink 30 first metal film 31 second metal film 32 first 3 metal film 33 solder 40 1st metal film 41 2nd metal film 42 3rd metal film 43 solder 50 Si substrate 51 4th metal film 52 5th metal film 53 6th metal film 71 oxide Substrate 72 Multi-layer thin film of nitride semiconductor 73 Electrode 74 Electrode 75 Heat sink 76 Solder 77 Metal film 100 Type electrode 101 Nitride-based semiconductor laminate 102 Nitride-based semiconductor laminate (InAlGaN multiple quantum well active layer) 103 Nitride-based semiconductor laminate 200 P-type electrode 201 Nitride-based semiconductor laminate 202 Nitride-based Semiconductor laminate (InGaNAsP multiple quantum well active layer) 203 Nitride-based semiconductor laminate 204 p-InAlGaN contact layer 205 p-InAlGaN cladding layer 206 p-InAlGaN guide layer 207 p-InAlGaN barrier layer 208 n-InAlGaN guide layer 209 n-InAlGaN cladding layer 300 semiconductor laser chip 301 semiconductor laser chip 302 semiconductor laser chip 303 semiconductor laser chip 401 Si substrate 402 device such as light receiving element 403 electrode 404 wire bond 405 c Da 406 semiconductor laser chip 407 wire bonds

Continued on the front page F term (reference) 5F041 CA04 CA05 CA34 CA40 CA82 CA85 CA86 CA87 CA92 CA98 DA32 5F073 AA61 AA74 CA17 CB02 CB23 DA30 DA34 EA28 FA14 FA22

Claims (13)

[Claims] 1. A semiconductor light-emitting device comprising: a support base; and a semiconductor light-emitting element mounted on the support base and provided with a nitride-based semiconductor laminate on a GaN substrate. A first metal film made of a material capable of forming an ohmic junction with the GaN substrate and functioning as an N-type electrode, and a high melting point metal formed on a surface opposite to the surface on which the body is provided. A semiconductor light emitting device, comprising: a second metal film that functions; and a third metal film made of a material that is easily mixed with solder, and having solder between the third metal film and the support base. 2. The method according to claim 1, wherein the thickness of the second metal film is at least 8 nm.
2. The semiconductor light emitting device according to claim 1, wherein the thickness is 0 nm or less. 3. A semiconductor light-emitting device comprising: a support base; and a semiconductor light-emitting element mounted on the support base and having a nitride-based semiconductor stacked body provided on a GaN substrate. A first metal film made of a material capable of forming an ohmic junction with the GaN substrate and functioning as an N-type electrode, and a high melting point metal formed on a surface opposite to the surface on which the body is provided. A second metal film that functions, and an alloy layer of a third metal and solder that is easily mixed with solder between the second metal film and the supporting base; A semiconductor light emitting device having a thickness of 8 nm or more and 80 nm or less. 4. The first metal film contains Al, the second metal film contains at least one of Mo, W, Cr, Ta, Zr and Mn, and the third metal film or The third metal is Au and N
4. The semiconductor light emitting device according to claim 1, comprising at least one of i. 5. The semiconductor light emitting device according to claim 1, wherein a crystal structure of the GaN substrate is hexagonal, and a mounting surface on the support base is substantially parallel to a c-plane. 6. The solder includes In, Sn, Zn, Au,
The semiconductor light emitting device according to claim 1, further comprising at least one of Pb, Ag, Cd, Bi, Ni, Mn, and Cu. 7. The device according to claim 7, wherein the supporting base is made of Si,
Metal film or the third metal is made of Au, Ni and Al
4. The method according to claim 1, further comprising at least one of the following.
Alternatively, the semiconductor light emitting device according to claim 5. 8. The support base is made of Si, and the solder is made of In, Sn, Zn, Au, Pb, Ag, Cd, and B.
i, Ni, Mn, Cu, claims 1 to 3 including at least one of SnCl ₂ and ZnCl _2, a semiconductor light emitting device according to claim 5 or claim 7. 9. The support base is made of Si, and Pt, Al, Ti, Cr, C is formed on the surface of the support base on the solder side.
2. A metal film containing at least one of o, Ni, Pd, Hf, W, Mo and Ta is provided.
The semiconductor light emitting device according to claim 8. 10. The support base is made of Si, and Au, Ni and A are provided on a portion of the support base which is in contact with the solder.
10. The semiconductor light emitting device according to claim 1, further comprising a metal film including at least one of l. 11. The semiconductor light emitting device according to claim 9, wherein a light receiving element is formed integrally with the supporting base made of Si. 12. The method for manufacturing a semiconductor light emitting device according to claim 1, wherein a wafer provided with a nitride-based semiconductor laminate on a GaN substrate is formed, and a surface of the GaN substrate on which the laminate is provided. The first metal film, the second metal film, and the third metal film
Forming a metal film of the above, dividing the wafer into semiconductor light emitting devices, bonding the substrate to a supporting base on which solder is previously laminated by heat treatment, or laminating solder on the third metal film and performing heat treatment And a step of adhering to a supporting substrate by the method. 13. The method for manufacturing a semiconductor light emitting device according to claim 2, wherein a wafer provided with a nitride-based semiconductor laminate on a GaN substrate is formed, and a surface of the GaN substrate on which the laminate is provided. The first metal film, the second metal film, and the third metal film
Forming a metal film, and dividing the wafer into semiconductor light emitting devices; and forming and bonding an alloy layer made of the third metal and solder by heat treatment with a supporting base on which solder is previously laminated; Or a step of laminating solder on the third metal film, forming an alloy layer composed of the third metal and solder by heat treatment, and bonding the alloy layer to a supporting base.