JP2000228565A - Nitride semiconductor laser device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nitride semiconductor laser device that has, because of easy processing, superior reproducibility, and superior beam characteristic, and operates with high output and low current. SOLUTION: Comprising a plurality of nitride semiconductor layers (Gax Iny Alz B1-x-y-z N: O<= x, y, z, x+y+z<=1) laterally growth-formed from an opening part formed on a substrate, a contact layer 18 comprising the nitride semiconductor layer, an active layer 14 comprising the nitride semiconductor layer formed on the contact layer 18, and clad layers 13 and 15 comprising the nitride semiconductor layers of conductive types different from each other, respectively, that are formed so as to sandwich the active layer 14, are provided. The active layer 14 and the clad layers 13 and 15 are, in a plurality of nitride semiconductor layer, so formed as to be a distance of film thickness of the contact layer, away from the opening in the lateral direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a Ga _x In _y Al _z B
_{The present} invention relates to a nitride semiconductor laser device comprising _1-xyz N (0 ≦ x, y, z, x + y + z ≦ 1) and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, short-wavelength semiconductor laser devices have been developed for application to high-density optical disk systems and the like. In this type of laser, it is required to shorten the oscillation wavelength in order to increase the recording density.

[0003] At present, there are 6 semiconductors made of InGaAlP-based semiconductors.
A semiconductor laser device having a 00 nm band light source has already been put to practical use with its characteristics improved to a level at which both reading and writing of a disk are possible. Therefore, in order to further improve the recording density, GaN-based semiconductor laser devices having an oscillation wavelength band from blue to blue-violet have been actively developed.

It has been reported that a GaN-based semiconductor laser device has an oscillation wavelength band of up to 350 nm or less and has a reliability of room temperature continuous oscillation for several thousands hours or more in terms of reliability. L in this system
Laser devices are promising in the future, for example, reliability of 10,000 hours or more has been confirmed for ED. Therefore, a GaN-based semiconductor is expected as an excellent material for a semiconductor laser device that satisfies the conditions required for a next-generation optical disk system light source.

In order to apply a semiconductor laser device to an optical disk system or the like, stable high-output laser characteristics are indispensable. For example, it is important to manufacture a semiconductor laser having a low threshold current value and sufficiently low thermal resistance. G
In the case of an aN-based semiconductor laser, since it is formed by vapor phase growth on a sapphire substrate, lattice mismatch with the substrate is large, so that dislocations and the like occur, and a satisfactory film quality is never obtained. .

In addition, since the sapphire substrate has low thermal conductivity, it has poor heat dissipation, and thus has a problem that it is impossible to obtain a high output of laser light. In addition, the sapphire substrate has a problem in that it is difficult to cleave the device because it is not easily cleaved, and it is difficult to perform chip assembly.

[0007]

As described above, the conventional nitride-based semiconductor laser has a problem in that a good-quality nitride-based semiconductor film is not formed on a sapphire substrate, and desired laser characteristics cannot be selected. Further, the sapphire substrate has a problem that high output of laser light cannot be obtained due to poor heat dissipation. Furthermore, sapphire substrates are difficult to cleave,
There is a problem that element separation is difficult and chip assembly is not easy.

The present invention has been made in view of the above circumstances, and provides a nitride semiconductor laser device having a low threshold current and high output laser characteristics. It is intended to provide a manufacturing method.

[0009]

In order to achieve the above object, the present invention provides a method of manufacturing a semiconductor device comprising a plurality of nitride-based semiconductor layers (Ga _x In _y Al) grown laterally from openings formed on a substrate.
_z B _1-xyz N: 0 ≦ x, y, z, x + y + z ≦ 1), and a nitride-based semiconductor layer (Ga _x In _y Al _z B _1-xyz N)
: 0 ≦ x, y, z , x + y + z ≦ 1 and the contact layer consists of), the contact nitride formed on layer based semiconductor layer _{(Ga x In y Al z B} 1-xyz N: 0 ≦ x, y , Z,
x + y + z ≦ 1) and a nitride-based semiconductor layer (Ga) having different conductivity types formed so as to sandwich the active layer.
_{x In y Al z B 1-} xyz N: 0 ≦ x, y, z, x + y + z
≦ 1), wherein the active layer and the cladding layer are separated from the plurality of nitride-based semiconductor layers in a lateral direction from above the opening by a distance equal to or more than the thickness of the contact layer. A nitride-based semiconductor laser device characterized by being formed is provided.

The present invention also provides a step of forming an SiO ₂ film having an opening on a first substrate, and a step of forming a plurality of nitride semiconductor layers (Ga _x In _y Al _z B _1-xyz N:
Forming 0 ≦ x, y, z, x + y + z ≦ 1);
This plurality of nitride-based semiconductor layer, the nitride-based semiconductor layer _{(Ga x In y Al z B} 1-xyz N: 0 ≦ x, y, z, x + y
+ Z ≦ 1) and a nitride-based semiconductor layer (Ga _x In _y Al _z B) formed on the contact layer.
_1-xyz N: an active layer composed of 0 ≦ x, y, z, x + y + z ≦ 1) and a nitride-based semiconductor layer of different conductivity type (Ga _x In _y Al _z B) formed so as to sandwich the active layer. _1-xyz N
Forming a cladding layer comprising: 0 ≦ x, y, z, x + y + z ≦ 1), wherein the active layer and the cladding layer have a thickness of the contact layer in a lateral direction from the opening. A method for manufacturing a nitride-based semiconductor laser device characterized by being formed at a distance above is provided.

Further, the present invention provides a step of forming a metal electrode having an outermost surface of Au on the plurality of nitride-based semiconductor layers after forming the active layer and the cladding layer; Forming a eutectic solder containing Au, vertically etching the nitride-based semiconductor laminated structure by using a photoresist or an insulator as a mask, and isolating elements; and forming a second surface having Au formed on the surface. Attaching the metal electrode on the substrate via the eutectic solder,
Removing the first substrate and the SiO ₂ film and removing the first substrate; and forming a high-reflection coating made of a high-dielectric thin-film laminated structure on a side surface of the laminated structure of the separated elements. And a method for cleaving or mechanically cutting the second substrate.

According to the present invention, an insulating film such as SiO ₂ having a stripe-shaped opening is formed on a substrate such as sapphire, and a nitride-based semiconductor film is laminated using the opening as a nucleus. As a result of the study of the present inventors, dislocations and voids are easily generated in the nitride-based semiconductor film on the opening, and good film quality cannot be obtained. It has been found that when formed, the laser characteristics are significantly reduced.

Therefore, the present inventors have found that dislocations and voids are unlikely to occur at a position farther than the thickness of the contact layer in the lateral direction from above the opening, and to select this position. It has been found that the laser characteristics can be improved by forming the active layer and the cladding layer.

Further, the present invention is characterized in that, after the active layer and the cladding layer are grown and formed, the insulator is etched and cleaved at the opening. In this case, at the time of cleavage, dislocations are easily generated on the opening, and the active layer and the cladding layer cannot be formed on the opening. Therefore, forming the active layer and the clad layer in a lateral direction from the opening has an effect of not damaging the element even when the element is removed through the opening.

Further, in the present invention, a crystal growth substrate such as a sapphire substrate which is not suitable for chip formation is removed and transferred to another substrate, thereby improving the assemblability and improving the heat radiation so as to achieve low current driving. It is intended to obtain good characteristics such as high output operation and beam condensing property.

Here, as a desirable mode of the present invention,
Examples include the following: The substrate to be transferred is preferably a semiconductor substrate or a substrate having a higher thermal conductivity than a nitride-based semiconductor laser. Further, it is preferable to integrate a light receiving device having a light receiving surface that is not perpendicular to the light emitted from the nitride semiconductor laser on this substrate. This makes it possible to easily form a module of the high-density optical disk system.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a sectional view of a blue semiconductor laser device according to a first embodiment of the present invention. FIG. 2
FIG. 3 is a perspective view of a semiconductor laser module in which this is assembled on a substrate.

As shown in FIG. 1, an SiO ₂ insulating film 11 having a stripe-shaped opening is formed on a sapphire substrate 10. On this SiO ₂ insulating film 11, a laterally grown n-GaN contact layer (Si-doped, 5 ×
10 ¹⁸ cm ⁻³ , 80 μm) 12, n-Al _0.08 Ga _0.92 N
Cladding layer (Si-doped, 5 × 10 ¹⁸ cm ⁻³ , 1.5 μm
m) 13, n-GaN optical waveguide layer (Si-doped, 1 × 10
¹⁸ cm ⁻³ , 0.1 μm) and a multiple quantum well active layer (In _0.15
Ga _0.85 N well layer (3 nm, 3 layers) / In _0.02 Ga _0.98
SCH-M comprising an N barrier layer (6 nm) and a p-GaN optical waveguide layer (Mg doped, 1 × 10 ¹⁸ cm ⁻³ , 0.1 μm)
QW (Separate Confinement Heterostructure Multi-Qu
qntum Well) Active layer 14, p-Al _0.08 Ga _0.92 N clad layer (Mg doped, 1 × 10 ¹⁸ cm ⁻³ , 1.5 μm) 1
5 are formed.

The n-cladding layer 13, the active layer 14, and the p-cladding layer 14 are formed in a ridge shape at a position laterally separated from the opening by a distance d. This position is set so that distance d ≧ contact layer thickness h. The ridge shape may be formed by etching, or an insulating film having an opening may be formed and selectively grown on the opening.

On the side surface of the ridge portion, p-In _0.1 G
a _0.9 N light absorbing layer (Mg doped, 2 × 10 ¹⁸ cm ⁻³ ,
5 μm) 16 is regrown, and n-Al _0.08 Ga
_0.92 N current blocking layer (Si-doped, 5 × 10 ¹⁸ c
m ⁻³ , 2 μm) 17 are buried. On these layers, a p-GaN contact layer (Mg doped, 2
× 10 ¹⁸ cm ⁻³ , 0.5 μm) 18 are formed. p
On the contact layer 18, a p-side electrode 18 made of Pt / Ti / Pt / Au and an AuSn eutectic solder layer (2 μm) 20 are formed.

Thereafter, the SiO ₂ insulating layer 11 is removed by etching, and the element is removed at the opening. As shown in Figure 2,
The laser element portion formed in 1 is formed on the c-BN mount. 21 is an n-side electrode made of Ti / Au, 23 is
These are Ti / Pt / Au pads.

In this embodiment, the width of the SCH-MQW active region 14 is 4 μm. Although not particularly shown, a high-reflection coating in which TiO ₂ (quarter wavelength thickness) / SiO ₂ (quarter wavelength thickness) is laminated in multiple layers is applied to the laser light emitting end face.

Next, referring to FIGS. 1, 2, 3, and 4,
A method for manufacturing the nitride semiconductor laser device will be described. First, an SiO ₂ layer 11 was formed on a surface of one side of a sapphire substrate 10 having both sides mirror-polished by a vapor phase growth (CVD) method for 200 nm.
m Deposits. Next, the SiO ₂ layer 11 is formed by photolithography.
Openings of 10 μm × 500 μm (500 μm × 1000 μm pitch) are opened until the sapphire substrate 10 is exposed to form a selective growth mask.

Next, metal organic chemical vapor deposition (MOCVD)
The n-GaN contact layer 12 and n-GaN
AlGaN cladding layer 13, SCH-MQW active region 1
4. The p-AlGaN cladding layer 15 is sequentially grown. Here, the n-GaN contact layer 12 may use hydride vapor phase epitaxy (HVPE) or the like. However,
In any of the crystal growth methods, it is desirable that the carrier gas be nitrogen from the start of the growth of the n-GaN contact layer 12 to immediately before the end of the growth. This is because, in the case of nitrogen carrier, the crystal growth rate in the horizontal direction is twice as fast as the crystal growth rate in the vertical direction. In the case of a hydrogen carrier, the growth rate is opposite to that in the case of a nitrogen carrier, and a high aspect ratio can be obtained. However, in any case,
The crystal growth temperature of the n-GaN contact layer 12 is set to 1200
It is desirable that the temperature be higher than or equal to ° C.

By setting the pitch of the SiO ₂ selective growth mask 11 to four times or more the total thickness of the nitride semiconductor layer on which the crystal grows, the crystal growth can be completed while being completely separated from the adjacent element. . The setting of the pitch is important for the temperature lowering process after the crystal growth. If the adjacent nitride semiconductor layers come into contact with each other, the sapphire substrate 10 as well as the nitride semiconductor layer will be cracked due to a difference in thermal expansion coefficient between the nitride semiconductor layer and the sapphire substrate 10 when the temperature is lowered. Not only has an effect, but the yield drops sharply.

Next, a SiO ₂ film is deposited again, and a mesa having a width of 4 μm is formed by photolithography so that the cavity direction is perpendicular to the {EMBED Equation.2,} direction of the nitride semiconductor layer. The position of the mesa stripe is parallel to the underlying SiO ₂ selective growth mask 11 and n-GaN in the lateral direction.
The contact layer 12 is formed at a position separated by more than the thickness. This is because the nitride semiconductor layer immediately above the opening of the underlying SiO ₂ selective growth mask 11 has many crystal dislocations, and this position has the lowest dislocation density.

Next, using the SiO ₂ stripe film as a mask, the p-InGaN light absorbing layer 16 and the n-type
After selectively growing the AlGaN current block layer 17 and removing the SiO ₂ stripe mask, the p-G
An aN contact layer 18 is grown.

Next, a p-side electrode 19 is deposited in the order of Pt / Ti / Pt / Au by using an electron beam evaporation method or a resistance heating method, and Au and Sn are alternately deposited so that the Sn weight composition is 20%. Then, the AuSn eutectic solder layer 20 is formed.

Next, a mask is formed on the mesa shape formed of the nitride semiconductor laminated structure with a photoresist so as to have a width of 400 μm and a cavity length of 500 μm, and the entire side surface including the light emitting end face is vertically etched by dry etching. Etch.

Next, as shown in FIG. 4, a c / BN (cubic boron nitride) substrate 22 (thickness: 300 μm) is
/ Au23 is sequentially deposited, and the Ti / Pt / Au surface is 800
A mesa stripe (1000 μm pitch, width 200 μm, depth 100 μm) is formed so as to remain with a width of μm.

Next, one side of the metallized stripe of the substrate 22 and one emission end face of the sapphire substrate 10 on which the nitride semiconductor laser is to be formed are bonded together, and thermally bonded at 320 ° C. for 30 seconds in a nitrogen atmosphere. Let it. Here, in the bonding step, when optically observed from the sapphire substrate 10 side, since the sapphire substrate 10 is transparent, an accuracy of about 1 μm can be easily obtained.

Next, the SiO ₂ selective growth mask 11 is completely removed by immersion in hydrofluoric acid, and the sapphire substrate 10 is peeled off by ultrasonic cleaning or by irradiating a laser beam from the sapphire substrate 10 side. Here, when the wafer from which the sapphire substrate 10 has been peeled off is optically observed, a height of 0.2 μm and a width of 10 μm are formed at the center of the n-GaN contact layer 12.
Only one step stripe can be confirmed per element.
This is achieved by MOCVD using the SiO ₂ selective growth mask 11.
It is formed in the initial stage of growth and is a feature of the device formed by the present invention. Since only this step stripe is in contact with the sapphire substrate 10 after hydrofluoric acid erosion,
The sapphire substrate 10 can be peeled off without causing element destruction by ultrasonic cleaning or laser irradiation.

Next, TiO is deposited by ECR-CVD (Electron Cyclotron Resonance CVD) or sputtering so that the thickness of the light emitting end face becomes one quarter of the laser oscillation wavelength.
_A high reflection coat 24 made of ₂ / SiO ₂ is formed.

Next, for taking out the electrode, n-GaN
Ti / Pt / A exposed all over contact layer 12
The insulating film composed of TiO ₂ / SiO ₂ on a part of the u-plane is peeled off, and Ti / Au is sequentially deposited. At this time, after forming the high reflection coat, the entire surface of the wafer is buried flat with a resin such as polyimide, and further, n-GaN is formed using a photoresist.
By exposing the entire surface of the contact layer 12 and part of Ti / Pt / Au to form an electrode extraction pad, an extremely thin laser package can be formed.

Next, c-BN is cut out by a diamond cutter dicing device or the like at a position in the groove of the c-BN substrate 22 and at a position for separating each element in the vertical direction thereof, and element separation is performed.

In this embodiment, when the resonator length is 0.5 mm, the threshold current is 30 mA, the oscillation wavelength is 405 nm, and the operating voltage is 4.5 V, and the continuous oscillation is performed at room temperature. 50 ° C, 50 ° C
The device life in mW driving was 5000 hours or more. Further, the far field pattern (FFP) had a single peak at a horizontal angle of 7 ° and a vertical angle of 22 °, and beam characteristics suitable for optical disc application were obtained.

In this nitride-based semiconductor laser device, the active layer 14 is not located immediately above the SiO ₂ selective growth mask 11,
Since it is formed in the region having the lowest dislocation density, leakage current is suppressed, oscillation can be performed with a low threshold current, and the active layer 1
The heat generated in step 4 is easily dissipated by c-BN having high thermal conductivity. Also, the outgoing light is c-B
Since the N step surfaces coincide with each other, not only light is not kicked out, but also the exit end surface can be brought close to the lens without mechanical damage to the lower part of the c-BN step.

Further, in the manufacturing process of the present invention, since the chip is already mounted at the stage of chip formation, errors in the mount assembly due to fine dust and the like generated in the normal chip formation including the cleavage method are eliminated. Without occurring
A semiconductor laser applicable to a high-density optical disk system can be easily obtained with a high yield.

In the case of a thin module substrate in which resin is embedded, it can be easily assembled in contact with a collimating lens. FIG. 5 is for explaining a schematic configuration of a blue semiconductor laser device according to a second embodiment of the present invention. This embodiment is different from the first embodiment in that c-B
That is, a mirror having a 45 ° facet is attached to the N substrate 22. Accordingly, although there is no particular change in the manufacturing method, the 45 ° f.
The SiO ₂ / TiO ₂ high reflection coating film 24 on the acet surface is used as a reflection mirror, and the laser portion is c-B.
At the time of thermocompression bonding to N, the alignment between the light emitting surface and the c-BN substrate is performed on the 45 ° facet side.

In this embodiment, the same characteristics as the laser characteristics of the first embodiment are shown. However, the light emission direction is horizontal in the first embodiment, but is vertical in the present embodiment. is there. Thereby, for example, it is easy to finally embed the resin flatly on the upper surface of the module in the modularization process including the wire assembly, and the module can be reduced in size.

FIG. 6 is a view for explaining a schematic configuration of a blue semiconductor laser device according to a third embodiment of the present invention. This embodiment is different from the first embodiment in that Si having a PIN photodiode having a light receiving surface of 45 ° face is used as the substrate 22 instead of c-BN. Therefore, there is no particular change in the manufacturing method, and a description thereof will be omitted.

In this embodiment, the maximum light output is reduced by about 10% due to poor heat radiation compared to the first embodiment, but other characteristics show the same characteristics as the laser characteristics of the first embodiment. Was. Also, since the emitted light on the rear side can be monitored in the vicinity,
The drive current control for maintaining the stable output of the emitted light was easily performed. This embodiment can easily be combined with the vertical light extraction of the second embodiment. The PIN photodiode is located at the 45 ° position because it is located at 45 ° on the Si substrate.
° Facing can be easily performed by etching with hydrofluoric nitric acid or potassium hydroxide, p-dopant diffusion and electrode forming process can be performed by the conventional technology, and the highest surface of the Si substrate is used for bonding with the nitride semiconductor substrate. This is to prevent so-called return light noise, which is generated when light emitted from the laser end face returns to the active layer by reflection, as well as to facilitate the manufacturing process such as being able to be set within a range not in contact with the sapphire substrate.

FIG. 7 is for explaining a schematic configuration of a blue semiconductor laser device according to a fourth embodiment of the present invention. This embodiment is different from the first embodiment in that two elements in series constitute one chip, one is a laser element, and the other is a light receiving element. The manufacturing method of the present embodiment is different from that of the first embodiment in that in the vertical processing of dry etching for forming a laser end face, the laser element forms a vertical surface on the active layer, whereas the light receiving element side takes measures against return light. In order to form a surface that is shifted by 10 ° only in the horizontal direction, and to form a high-reflection coating on the light-emitting end face, the laser element is coated on both sides, whereas the light-receiving element is coated on the incident side. That is not. In the actual process, the photoresist mask for dry etching may be formed on the laser element side perpendicular to the active layer and on the light receiving element side in an 80 ° direction with respect to the active layer. Further, the high reflection coating film on the incident surface on the light receiving element side may be previously covered with a photoresist mask, or may be removed by etching after coating.

In this embodiment, the c-BN substrate 22 is used. However, when a semiconductor substrate such as Si is used, a Si substrate (a substrate on which a drive circuit is integrated) is used to electrically separate the laser element and the light receiving element. However, a SiO ₂ insulating film may be inserted between the Ti / Pt / Au surface.

In this embodiment, characteristics similar to the laser characteristics of the first embodiment were exhibited. Further, the same drive current control as in the third embodiment could be easily performed. In this embodiment, since the laser element and the light receiving element can be easily formed at the same time, the manufacturing process is not complicated, and the yield is high.

The present invention is not limited to the present embodiment. As the substrate 22, not only a semiconductor such as Si or GaAs but also a semiconductor substrate on which a laser driving circuit or a light receiving signal processing circuit is integrated, or a substrate made of SiC or diamond. And a single crystal substrate such as AlN, and a ceramic substrate such as AlN. Further, in the laser structure, various applications are possible without departing from the gist of the present invention.

[0047]

As described above in detail, according to the present invention, a nitride-based semiconductor laser having a low threshold value, good beam characteristics, and an easy manufacturing method can be realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a nitride semiconductor laser according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a nitride semiconductor laser according to a first embodiment of the present invention.

FIG. 3 is a diagram illustrating a method for manufacturing the nitride semiconductor laser according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a method for manufacturing a nitride semiconductor laser according to the first embodiment of the present invention.

FIG. 5 is a sectional view of a nitride semiconductor laser according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a nitride semiconductor laser according to a third embodiment of the present invention.

FIG. 7 is a sectional view of a nitride semiconductor laser according to a fourth embodiment of the present invention.

[Explanation of symbols]

10 ... sapphire substrate 11 ... SiO ₂ selective growth mask 12, ... n-GaN contact layer _{13 ··· n-Al 0.08 Ga 0.92} N clad layer 14 ... SCH-MQW active region 15.. p-Al _0.08 Ga _0.92 N cladding layer 16 ... p-In _0.1 Ga _0.9 N light absorbing layer 17 ... n-Al _0.08 Ga _0.92 N current blocking layer 18 ... p-GaN contact layer 19 ... p-side electrode 20 ... AuSn eutectic solder layer 21 ... n-side electrode 22 ... c-BN mount 23 ... Ti / Pt / Au pad 24 ... high reflection coating

Claims (3)

[Claims] A plurality of nitride-based semiconductor layers (Ga _x In _y Al _z) grown laterally from openings formed on a substrate.
B _1-xyz N: 0 ≦ x, y, z, x + y + z ≦ 1), and a nitride-based semiconductor layer (Ga _x In _{y Alz} B _1-xyz N: 0 ≦
x, y, z, x + y + z ≦ 1) and a nitride-based semiconductor layer (Ga _x In _y Al _z B _1-xyz N: 0 ≦ x, y, z, x + y
+ Z ≦ 1) and a nitride-based semiconductor layer of different conductivity type (Ga _x In _y ) formed so as to sandwich the active layer.
Al _z B _1-xyz N: 0 ≦ x, y, z, x + y + z ≦ 1)
The active layer and the cladding layer are formed in the plurality of nitride-based semiconductor layers in a lateral direction from above the opening, and are formed apart from the contact layer by a thickness equal to or more than the thickness of the contact layer. A nitride-based semiconductor laser device. A step of forming an SiO ₂ film having an opening on the first substrate; and forming a plurality of nitride-based semiconductor layers (Ga _x In _y ) on the first substrate.
Al _z B _1-xyz N: 0 ≦ x, y, z, x + y + z ≦ 1)
Forming a, while the plurality of the nitride-based semiconductor layer, the nitride semiconductor layer _{(Ga x In y Al z B} 1-xyz N: 0 ≦ x, y, z, x + y
+ Z ≦ 1) and a nitride-based semiconductor layer (Ga _x In _y Al _z B) formed on the contact layer.
_1-xyz N: an active layer composed of 0 ≦ x, y, z, x + y + z ≦ 1) and a nitride-based semiconductor layer of different conductivity type (Ga _x In _y Al _z B) formed so as to sandwich the active layer. _1-xyz N
Forming a cladding layer comprising: 0 ≦ x, y, z, x + y + z ≦ 1), wherein the active layer and the cladding layer have a thickness of the contact layer in a lateral direction from the opening. A method for manufacturing a nitride-based semiconductor laser device, which is formed at a distance above. 3. A step of forming a metal electrode having an outermost surface of Au on the plurality of nitride-based semiconductor layers after forming the active layer and the cladding layer; and including Au on the metal electrode. A step of forming a eutectic solder, a step of vertically etching the nitride-based semiconductor multilayer structure using a photoresist or an insulator as a mask, and separating the elements, and a step of forming an Au on the surface of the second substrate. Attaching the metal electrode via the eutectic solder, removing the first substrate and the SiO ₂ film, and removing the first substrate; and removing the first substrate. 3. The nitriding method according to claim 2, further comprising: forming a high-reflection coating made of a high-dielectric thin-film laminated structure on a side surface of the laminated structure; and cleaving or mechanically cutting the second substrate. Of semiconductor laser devices Law.