JP2002164617A - Semiconductor laser device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a Gaussian beam of high reliability and high quality from low power to high power, in a semiconductor laser device composed of GaN based material. SOLUTION: An N-GaN contact layer 15, an N-Ga1-z1Alz1N/GaN super lattice clad layer 16, an N-Ga1-y2Aly2N optical waveguide layer 17, an Inx2Ga1-x2N/Inx1 Ga1-x1N multiple quantum well active layer 18, a P-Ga1-y3Aly3N carrier blocking layer 19, a P-Ga1-y2Aly2N optical waveguide layer 20, a P-Ga1-z1Alz1N/GaN super lattice clad layer 21 and a P-GaN contact layer 22 are grown in this order on a GaN film 14. Etching is performed as far as the super lattice clad layer 21, and a ridge part is formed. The contact layer 22 of a region (L) of an end surface of the ridge part is eliminated, an insulating film 26 is formed, and the vicinity of the end surface is made a part in which a current is not injected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser device made of a GaN-based semiconductor.

[0002]

2. Description of the Related Art In a field such as an optical disk memory and printing using a photosensitive material, a 400 nm band semiconductor laser having a minute spot has a light density with a reliability of Gaussian distribution due to its high density and high image quality. There is a demand for high quality beams. For example, as a short-wavelength semiconductor laser in the 410 nm band, Jpn. J. Appl. Phys.
t., Vol. 37, pp. L1020, InGaN / GaN by Nakamura et al.
/ AlGaN-Based Laser Diodes Grown on GaN Substrates
With a Fundamental Transverse Mode, after forming GaN on a sapphire substrate, forming a GaN layer using selective growth using SiO ₂ as a mask, and removing GaN from the sapphire substrate to a part of the GaN layer N-
GaN buffer layer, n-InGaN crack prevention layer, n-AlGaN / GaN
Modulation-doped superlattice cladding layer, n-GaN optical waveguide layer, n-InGaN
A semiconductor laser has been reported that has a multi-layered InGaN / InGaN multiple quantum well active layer, p-AlGaN carrier blocking layer, p-GaN optical waveguide layer, p-AlGaN / GaN modulation-doped superlattice cladding layer, and p-GaN contact layer. I have.

[0003]

SUMMARY OF THE INVENTION
Although the element resistance is reduced by using the modulation-doped superlattice cladding layer, it is not sufficient, so that the reliability is degraded due to Joule heat during driving. Heat generation is particularly remarkable at the cavity end face where the light density is high. Although the generation of Joule heat is dealt with by cooling using a heat sink or the like, the n-electrode cannot be formed on the back surface of the GaN substrate because the thermal conductivity of the GaN substrate is low in the above element structure. ,
Since the device side surface is formed on the exposed n-GaN layer by etching, it is difficult to cool from the p-electrode side close to the active layer where the device shape is complicated and generate heat, and n
Since cooling can be performed only from the electrode surface, heat radiation is not sufficient. Therefore, the mode of the oscillation beam is disturbed with the increase in the output.

Therefore, in order to reduce heat generation at the end face of the resonator due to an increase in output, a current non-injection region is provided so that current injection near the end face of the resonator is suppressed.

The present invention has been made in view of the above circumstances, and has been described in view of heat generation of an element.
In particular, it is an object of the present invention to provide a highly reliable semiconductor laser device having a high quality beam having a uniform Gaussian distribution of light density from low output to high output by reducing heat generation at a cavity end face. It is.

[0006]

A semiconductor laser device according to the present invention comprises a GaN layer provided with one of a pair of electrodes, at least a first conductivity type cladding layer made of a GaN-based semiconductor, an active layer, and a GaN-based semiconductor layer. In the semiconductor laser device in which the second conductivity type cladding layer, the second conductivity type GaN contact layer, and the other electrode are laminated in this order, at least one of the two cavity facets facing each other has a current non-contact area. It is characterized by being an injection region.

It is desirable that the current non-injection region ranges from 5 μm to 50 μm from the end face toward the inside of the device.

[0008] The current non-injection region may be formed by removing the second conductivity type GaN contact layer near the end face.

An insulating film is formed so as to cover the second conductivity type cladding layer exposed near the end face and the second conductivity type contact layer inside the vicinity of the end face. An opening for current injection may be provided on the two-conductivity-type contact layer, and the other electrode may be formed so as to cover the opening. That is, the opening may be formed continuously from above the contact layer to the second conductivity type cladding layer near the end face, which is a current non-injection region.

The current non-injection region may be formed by forming the other electrode in a region other than the vicinity of the end face.

Note that the GaN-based material is at least Ga
And N are included in the constituent elements.

[0012]

According to the semiconductor laser device of the present invention, at least G is formed on the GaN layer provided with one of the pair of electrodes.
a first conductivity type cladding layer made of an aN-based semiconductor, an active layer, a second conductivity type cladding layer made of a GaN-based semiconductor,
A semiconductor laser device in which a second-conductivity-type GaN contact layer and the other electrode are laminated in this order, and a region near at least one of two opposing optical cavity end surfaces is a current non-injection region. As a result, since no current is injected near the optical resonator end face, non-radiative recombination current is reduced, and heat generation at the end face can be reduced. Therefore, since disturbance of the oscillation mode due to heat generation can be suppressed, a high-quality Gaussian distribution beam from low output to high output can be obtained.

It is preferable that the current non-injection region ranges from 5 μm to 50 μm from the end face toward the inside of the device. When the thickness is smaller than 5 μm, the current easily spreads to the end face, and a substantially non-current injection region cannot be formed. On the other hand, when it is larger than 50 μm, light loss due to light absorption in the non-current injection region increases, and the light output decreases.

The current non-injection region is preferably formed by removing the second conductivity type GaN contact layer in the vicinity of the end face. Injection is suppressed,
Non-radiative recombination current is reduced, and heat generation at the end face can be reduced. Therefore, a high-quality Gaussian oscillation beam can be obtained from a low output to a high output.

The current non-injection region may be one in which the other electrode is formed in a region other than the vicinity of the end face. Injection of current at the end face is suppressed, and non-radiative recombination current is reduced. In addition, heat generation at the end face can be reduced. Accordingly, a high-quality Gaussian oscillation beam from low output to high output can be obtained.

[0016]

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

The semiconductor laser device according to the first embodiment of the present invention will be described along the manufacturing process. FIG. 1 shows a perspective view of the semiconductor laser device. Note that trimethylgallium (TMG), trimethylindium (TMI), trimethylaluminum (TMA) and ammonia were used as raw materials for growing each semiconductor layer described below, and silane gas was used as an n-type dopant gas, and p-type Cyclopentadienyl magnesium (Cp ₂ Mg) is used as a dopant.

As shown in FIG. 1, metalorganic vapor phase epitaxy
Thickness on the (0001) C-plane sapphire substrate 11 at 500 ° C
A GaN low-temperature layer 10 of 30 nm is formed, and a low-pressure 1.33
× 10^Four(Pa) and a GaN buffer layer 12 of about 2 μm thickness
It is formed with a thickness. 0.1 μm thick SiO_TwoFilm 13 with P-CVD equipment
Formed and photolithographically etched at 5 μm at intervals of 2 μm.
μm wide SiO_TwoForm a stripe pattern to leave film 13
Followed by this SiO_Two2 on the mask pattern by the film 13
A GaN film 14 having a thickness of 0 μm is grown. Then, n-G
aN contact layer 15, n-Ga_1-z1Al_z1N (2.5nm) / G
aN superlattice cladding layer (2.5 nm) 16, n-Ga_1-y2Al_y2
N optical waveguide layer 17, In_x2Ga_1-x2N (Si-doped) / In_x1
Ga_1-x1N multiple quantum well active layer (0.5> x1> x2 ≧ 0) 18,
p-Ga _1-y3Al_y3N carrier blocking layer 19, p-G
a_1-y2Al_y2N optical waveguide layer 20, p-Ga_1-z1Al_z1N (2.5
nm) / GaN (2.5 nm) superlattice cladding layer 21, p-GaN layer
A contact layer 22 (not shown) is grown.

Subsequently, the SiO_TwoMembrane 23 (not shown) and resist
24 (not shown) and are formed by ordinary lithography.
Resist 24 (not shown) other than 3 μm wide ridge
And SiO _TwoThe film 23 (not shown) is removed. RIE (Reactive Io
P-Ga by selective etching
_1-z1Al_z1N (2.5 nm) / GaN (2.5 nm) superlattice cladding layer 2
Etching is performed part way. Clutch by etching
The remaining thickness of the pad layer 21 is the thickness that can achieve the fundamental transverse mode oscillation.
And Next, a resist 24 (not shown) and SiO_TwoMembrane 23
(Not shown), then remove the SiO 2_TwoMembrane (shown
) And a resist (not shown).
3 μm wide ridge created earlier by lithography
Resist and Si other than the 10 μm wide region
O_TwoRemove the film (3μ width is located at the center of 10μm width area)
Is preferably placed). Next, RIE (reactive ion
Etching) Selective etching with equipment, n-GaN
Etching is performed up to the layer contact layer 15.

Next, after removing the resist and the SiO ₂ film, the Si
The O ₂ film 25 (not shown) and the resist are formed again, and the resist is formed from the expected end face position formed by the cleavage to the position (L) that enters the 25 μm resonator side on the ridge by a normal photolithographic etching technique. Film and SiO ₂ film 25
(Not shown) is removed by etching. After selectively etching the p-GaN contact layer 22 near the end face by RIE, the resist and the SiO ₂ film 25 (not shown) are once removed.

The SiO ₂ film 26 is formed again, the resist on the ridge portion and the SiO ₂ film 26 are removed by a usual photolithographic etching technique, and a region of the SiO ₂ film 26 where current is injected is opened.
At this time, the opening where the SiO ₂ film 26 is etched is on the p-GaN contact layer 22 on the ridge. Next, Ni / Au
A p-electrode material is formed, and the resist and p-electrode material other than the opening are peeled off by a lift-off method to form a p-electrode 27 on the p-GaN contact layer.

Thereafter, a resist is applied again and n-Ga
The SiO ₂ film 26 on the N-layer contact layer 15 is coated with p by photolithography.
Form a stripe opening of 10 μm width parallel to the ridge stripe formed on the electrode surface, form an n-electrode material made of Ti / Al, peel off the resist other than the opening by lift-off method, n-electrode material, An n-electrode 28 is formed on the n-GaN contact layer 15.

Next, the sapphire substrate 11 is
Polish to a thickness of μm. Applying a high reflectance coating to one of the resonator surfaces formed by cleaving the sample prepared as described above,
On the other side, a non-reflection coating is performed. Thereafter, the semiconductor laser device is formed by chipping.

In the present semiconductor laser device, the p-GaN contact layer 22 near the end face of the ridge portion is removed, and the Si
An O ₂ film 26 is formed to form a current non-injection region a. Since there is no contact layer at the end faces, no ohmic junction is made, so that the injection current at both end faces is reduced. Therefore, non-radiative recombination current is reduced, and heat generation is reduced. Therefore, a high-quality Gaussian beam can be obtained up to a high output.

The composition of GaAlN is as follows: 1>z1> y2 ≧ 0;
0.4>y3> y2.

The equivalent refractive index of light propagating in the vertical direction at both end faces on both sides of the ridge is defined as nA, the equivalent refractive index of light propagating in the vertical direction of the ridge portion is defined as nB, and p-Ga _{1 -z 1} Al _z1 N
By controlling the thickness of the (2.5 nm) / GaN (2.5 nm) superlattice cladding layer 21, the equivalent refractive index step nB-nA is reduced by 7 × 10
^-3 >nB-nA> 1.5.times.10.sup.- ³ .

It is also possible to use a SiN film instead of the SiO ₂ film 26. When an SiN film is used, the film becomes denser, it is possible to reduce a leak current due to a defect or the like, and an improvement in yield is expected.

FIG. 2 shows a graph of a reliability test result of the aging test of the semiconductor laser device. The horizontal axis indicates time, and the vertical axis indicates drive current. The driving conditions of the semiconductor laser device were such that the output was 1 mW, the APC was driven, and the ambient temperature was 50 ° C. In the figure, (a) shows the characteristics of the conventional semiconductor laser device, and (b) shows the characteristics of the semiconductor laser device shown in the first embodiment. The structure of the conventional semiconductor laser device is the same as that of the semiconductor laser device of the present invention.
The structure is such that the p-GaN contact layer 22 on the end face of the resonator is not removed, and a current is injected also into the end face of the resonator.

As shown in FIG. 2A, the conventional semiconductor laser device is deteriorated in about 80 hours, but as shown in FIG. 2B, the semiconductor laser device of the present invention is deteriorated by about 400 hours.
The current increase is only 1.4 times.

Next, a semiconductor laser device according to a second embodiment of the present invention will be described along the manufacturing process. FIG. 3 shows a perspective view of the semiconductor laser device. The fabrication of the GaN substrate 35 'is the same as the fabrication up to the GaN layer 14 according to the first embodiment. As a raw material for growing each semiconductor layer described below, trimethyl gallium (TMG), trimethyl indium (TMI), trimethyl aluminum (TMA) and ammonia are used as raw materials, a silane gas is used as an n-type dopant gas, and a p-type dopant is used. As cyclopentadienyl magnesium (Cp ₂ Mg). A 30-nm-thick GaN low-temperature layer 1 at 500 ° C. on a (0001) C-plane sapphire substrate 11 by metalorganic chemical vapor deposition.
0, and a low pressure of 1.33 × 10 ⁴ (Pa)
The aN buffer layer 12 is formed with a thickness of about 2 μm. 0.
A 1 μm thick SiO ₂ film 13 is formed by a P-CVD apparatus, and a stripe pattern is formed by photolithographic etching so as to leave an SiO ₂ film 13 with a width of 2 μm and a width of 5 μm.
A 20 μm thick GaN film 14 is grown on the O ₂ mask pattern. Up to this point, the operation is the same as that of the first embodiment.
Further, a non-doped GaN film 35 (not shown) having a thickness of 200 μm is grown at 1000 ° C. using HVPE (hydride vapor phase epitaxy). Here, the sapphire substrate 11
Non-doped GaN layer 35 grown by HVPE from the back of
The non-doped GaN substrate 35 'is manufactured by cutting and polishing to a thickness of 0 μm.

Subsequently, the n-GaN contact layer 36, n
_{-Ga 1-z1 Al z1 N (} 2.5nm) / GaN superlattice cladding layer
(2.5 nm) 37, n-Ga _1-y2 Al _y2 N optical waveguide layer 38, In _x2
Ga _{1-x 2} N (Si- _{doped) / In x1 Ga 1-x1} N multiple quantum well active layer (0.5>x1> x2 ≧ 0 ) 39, p-Ga 1-y3 Al y3 N
Carrier blocking layer 40, p-Ga _1-y2 Al _y2 N optical waveguide layer 41, p-Ga _1-z1 Al _z1 N (2.5 nm) / GaN (2.5 nm)
A superlattice cladding layer 42 and a p-GaN contact layer 43 (not shown) are grown.

Subsequently, an SiO ₂ film 44 (not shown) and a resist are formed, and the resist and the SiO ₂ film 44 other than the ridge portion having a width of 50 μm are removed by ordinary lithography. RIE
(Reactive ion etching) Etching is performed halfway of the p-type superlattice cladding layer 42 by selective etching using an apparatus. The remaining thickness of the cladding layer in this etching is a thickness that can achieve the fundamental transverse mode oscillation. Thereafter, the resist and the SiO ₂ film 44 are once removed, a SiO ₂ film 45 (not shown) is formed again, and a 20 μm resonator side from a predetermined end face position formed by cleavage at the upper portion of the ridge by a normal photolithographic etching technique. Then, the resist and the SiO ₂ film 45 are removed by etching up to the position (L) where the resist enters. P-GaN with RIE
After selectively etching the contact layer 43, the resist and
The SiO ₂ film 45 is once removed. The insulating film SiO ₂ film 46 is formed again.

Next, an opening having a width (W) is formed in the SiO ₂ film 46 above the ridge by a usual photolithographic etching technique. A p-electrode 47 made of Ni / Au is formed over the p-type superlattice cladding layer near the end face and on the p-type contact layer inside the vicinity of the end face. Non-doped GaN formed by HVPE method
A 200 μm wide (W ′) stripe opening parallel to the stripe formed on the p-electrode surface is formed in the substrate 35 ′ by photolithography, and the n-GaN contact is formed by ECR dry etching using Cl ₂ gas. Etching is performed up to the layer 36 surface. After stripping the resist, an n-electrode made of Ti / Al is formed on the entire surface of the non-doped GaN substrate 35 'formed by HVPE including the groove.
Form 48. Then, after forming a solvent containing an Au material as shown in JP-A-10-22574 by spin coating,
By performing annealing at about 400 ° C. for 30 minutes, the Au layer 49 in which the concave portion is buried flat is formed. One of the resonator surfaces formed by cleaving the sample is coated with a high reflectivity, and the other is coated with a non-reflective coating. Thereafter, it is chipped to complete a semiconductor laser device. This element is bonded to the heat sink on the n side using AuSn brazing material.

The semiconductor laser device according to the present embodiment is
The p-GaN contact layer 43 near the end face of the ridge is removed, an insulating film 46 having an opening and a p-electrode 47 are formed thereon, and a current non-injection region a is formed.
In the region a, since there is no p-GaN contact layer 43,
Since the p-GaN contact layer 43 and the p-electrode 47 are not in contact with each other and no ohmic junction is made, no current is injected and the non-radiative recombination current can be reduced. Therefore, since heat generation at the end face can be reduced, a high quality Gaussian beam can be obtained up to a high output.

The composition of GaAlN is as follows: 1>z1> y2 ≧ 0, 0.4
>Y3> y2.

The equivalent refractive index of light propagating in the vertical direction of the bottom side on both sides of the ridge is defined as nA, the equivalent refractive index of light propagating in the vertical direction of the ridge portion is defined as nB, and p-Ga _{1 -z 1} Al _z1 N
By controlling the thickness of the (2.5 nm) / GaN (2.5 nm) superlattice cladding layer 42, the equivalent refractive index step nB-nA becomes 7 × 10
^-3 >nB-nA> 1.5.times.10.sup.- ^3, and the equivalent refractive index step can be controlled.

The insulating film is not limited to the SiO ₂ film but may be a SiN film.

The n-electrode 48 is connected to a non-doped GaN substrate 35 '.
The current injected from the p-electrode side flows uniformly, and a stable Gaussian beam can be obtained even in a 50 μm width ridge stripe by forming a contact directly with the exposed n-GaN contact layer 36 by partially etching Becomes possible. In addition, since non-injection regions are formed at both end surfaces, non-radiative recombination current can be reduced, so that heat generation is reduced.

Further, since the groove on the n-electrode side is buried with an Au material and flattened, and the bonding to the heat sink is performed uniformly, the effect of cooling the heat generated by the element is high, and highly reliable laser emission is realized. It is possible.

After the grooves are formed in the GaN substrate 35 ', a heat sink provided with a passage for the cooling medium may be attached to the substrate side without embedding Au, and the cooling medium may flow into the grooves. Thereby, it becomes easy to effectively release the heat generated by the element.

In the semiconductor laser device according to the above two embodiments, the region where the p-GaN contact layer is etched enters the cavity side of 5 μm minimum and 50 μm at maximum including the end face from the expected end face position formed by cleavage. It is desirable to be within the position. By making the current non-injection at both end portions of the laser element, non-radiative recombination current at both end portions is reduced, and heat generation is reduced. Therefore, it is possible to provide a Gauss-type, high-quality, high-reliability laser element from low output to high output.

Next, a semiconductor laser device according to a third embodiment of the present invention will be described along its manufacturing process. FIG. 4 shows a perspective view of the semiconductor laser device. As a raw material for growing each semiconductor layer described below, trimethyl gallium (TMG), trimethyl indium (TMI), trimethyl aluminum (TMA) and ammonia are used as raw materials, and n
Silane gas as the p-type dopant gas and cyclopentadienyl magnesium (Cp ₂ M
Use g). (0001) C by metal organic chemical vapor deposition
1.33 × 10 ⁴ (Pa) of low pressure on the surface sapphire substrate 51
To form a GaN buffer layer 52 with a thickness of about 2 μm.
A 0.1 μm thick SiO ₂ film 53 is formed by a P-CVD apparatus, and a 5 μm wide SiO ₂ film is formed at 2 μm intervals by photolithographic etching.
A stripe pattern is formed so as to leave 53, and a GaN layer 54 having a thickness of 20 μm is grown on the SiO ₂ mask pattern. Subsequently, the n-GaN contact layer 55, n-
Ga _{1- z1} Al _z1 N (2.5 nm) / GaN superlattice cladding layer (2.5
nm) 56, n-Ga _1-y2 Al _y2 N optical waveguide layer 57, In _x2 Ga
_1-x2 N (Si- _{doped) / In x1 Ga 1-x1} N multiple quantum well active layer (0.5>x1> x2 ≧ 0 ) 58, p-Ga 1-y3 Al y3 N carrier blocking layer 59, p-Ga _1-y2 Al _y2 n optical waveguide layer _{60, p-Ga 1-z1} Al z1 n (2.5nm) / GaN (2.5nm) superlattice first clad layer _{61, n-Al x4 Ga 1} -x4 n (x4> x
3) Grow current blocking layer 62. Subsequently, the resist in a portion serving as a current injection region having a width of 3 μm is removed by ordinary lithography, and the n-Al _x4 Ga _{1 -x4N} current blocking layer 62 is etched by a RIE (reactive ion etching) device. After removing the resist, to grow a _{p-Al x3 Ga 1-x} 3 N second cladding layer 63, p-GaN contact layer 64. Etching is performed by a reactive ion etching method until the n-GaN contact layer 55 is exposed, using an SiO ₂ mask in which a region on the side of the current injection region is opened by photolithography. A p-electrode 65 made of Ni / Au is formed in a region other than near the end face of the surface of the p-GaN contact layer 64. Since the p-electrode is formed by the lift-off method, the p-electrode material at the laser end surface scheduled portion is not formed in advance. The region where the p-electrode 65 is not formed is 5 μm or more from the end surface including the end surface.
It is desirable that the range is not more than μm. Thereafter, on the n-GaN contact layer 55 exposed by the reactive ion etching method, a 10 μm-wide stripe opening parallel to the stripe formed on the p-electrode side is formed by the photolithography method, and n / n of Ti / Al is formed. An electrode material is formed. The resist and the n-electrode material other than the opening are peeled off by the lift-off method to form the n-electrode 66. The sapphire substrate 51 is polished to a thickness of 70 μm by a polishing method. A high-reflectance coat is applied to one of the resonator surfaces formed by cleaving the sample manufactured as described above, and a non-reflection coat is applied to the other.

The composition of GaAlN is as follows: 1>z1> y2 ≧ 0, 0.4
>Y3> y2, x4> x3.

The equivalent refractive index of light propagating in the vertical direction in the region where the current confinement layer exists is nA, and the equivalent refractive index of light propagating in the vertical direction in the region where the current confinement layer does not exist is nB.
By controlling the thickness of the p-Ga _{1 -z 1} Al _z1 N (2.5 nm) / GaN (2.5 nm) superlattice first cladding layer 61, 7 × 10 ⁻³ > n
B-nA> 1.5 × 10 ⁻³ and the equivalent refractive index step can be controlled.

A GaN low-temperature layer formed at 500 ° C. between the sapphire substrate 51 and the GaN buffer layer 52 has a thickness of 30 nm.
It may be formed with a thickness of about.

Since the semiconductor laser device of the present invention emits a high-quality and highly-reliable beam having a Gaussian distribution from low output to high output, it can be used for high-speed information / image processing, communication, measurement, medical care, and printing. It can be applied as a light source in a computer.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a semiconductor laser device according to a first embodiment of the present invention.

FIG. 2 is a graph showing the aging reliability test results of the present invention and a conventional semiconductor laser device;

FIG. 3 is a perspective view showing a semiconductor laser device according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a semiconductor laser device according to a third embodiment of the present invention.

[Explanation of symbols]

11 (0001) C-plane sapphire substrate 10 GaN low-temperature layer 12 GaN buffer layer 13 SiO ₂ film 14 GaN layer 15 n-GaN contact layer 16 n-Ga _1-z1 Al _z1 N / GaN superlattice cladding layer 17 n-Ga _{1 -y2} Al _y2 N optical waveguide layer 18 In _x2 Ga _1-x2 N / In _x1 Ga _1-x1 N multiple quantum well active layer 19 p-Ga _1-y3 Al _y3 N carrier blocking layer 20 p-Ga _1-y2 Al _y2 N optical waveguide layer 21 p-Ga _1-z1 Al _z1 N / GaN superlattice cladding layer 26 insulating film 27 p electrode 28 n electrode

Claims (5)

[Claims] A first conductive type clad layer made of a GaN-based semiconductor, an active layer, a second conductive type clad layer made of a GaN-based semiconductor, A semiconductor laser device in which a two-conductivity type GaN contact layer and the other electrode are laminated in this order, wherein at least one of two opposing resonator end faces is near a current non-injection region. Laser element. 2. The semiconductor laser device according to claim 1, wherein said current non-injection region ranges from 5 μm to 50 μm from an end face toward the inside of the device. 3. The semiconductor laser device according to claim 1, wherein the current non-injection region is formed by removing the second conductivity type GaN contact layer near the end face. 4. An insulating film is formed so as to cover the second conductive type cladding layer exposed near the end face and the second conductive type contact layer inside the vicinity of the end face. 4. The semiconductor laser device according to claim 3, wherein an opening for injecting current is provided at least on said second conductivity type contact layer, and said other electrode is formed so as to cover said opening. 5. The semiconductor laser device according to claim 1, wherein the current non-injection region is formed by forming the other electrode in a region other than near the end face.