JP2000012970A - Semiconductor light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device with a nitride base group III-V compound semiconductor which can be implemented with a high reliability. SOLUTION: A GaN base semiconductor layer, forming a laser construction, is formed on a first major surface of a sapphire substrate 1. A p-side electrode 16 is formed on the GaN base semiconductor layer higher than an n-side electrode 17 to form a GaN base semiconductor laser. In this case, grooves 12 and 13 are formed in parallel in the upper side of the GaN base semiconductor layer in a p-side electrode forming area, and a ridge 14 is formed between them. A p-side electrode 16 is formed, covering the ridge 14 and the grooves 12 and 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light emitting device, and more particularly, to a semiconductor light emitting device which is suitably applied to a semiconductor laser or a light emitting diode using a nitride III-V compound semiconductor such as GaN.

[0002]

2. Description of the Related Art A GaN-based semiconductor is a direct transition semiconductor, and has a forbidden band ranging from 1.9 eV to 6.2 eV. It is possible to realize a light emitting device capable of emitting light in a visible region to an ultraviolet region. For this reason, it has attracted attention in recent years, and its development is being actively promoted.

As the GaN-based semiconductor light emitting device, a light emitting diode has already been put to practical use. The practical use of this GaN-based light-emitting diode has not only provided a short-wavelength light source in the wavelength range of green to ultraviolet, but also has ensured its application to full-color displays, etc. by providing a high-luminance three-primary-color light-emitting diode light source. became. On the other hand, although the GaN-based semiconductor laser has not been put to practical use yet, continuous oscillation at room temperature has already been achieved, and the life of the GaN-based semiconductor laser has been extended.

FIG. 17 shows a ridge structure and SCH (Separa).
1 shows an example of a conventional GaN-based semiconductor laser having a te Confinement Heterostructure) structure.

As shown in FIG. 17, in this GaN-based semiconductor laser, an undoped GaN layer 103, an n-type GaN contact layer 104, an undoped GaN buffer layer 102 formed on a c-plane sapphire substrate 101 via a low-temperature growth. n-type AlGaN cladding layer 105, n-type Ga
N optical waveguide layer 106, Ga _1-x In _x N / Ga _1-y In _y
N-quantum well active layer 107, p-type AlGaN cap layer 108, p-type GaN optical waveguide layer 109, p-type Al
A GaN cladding layer 110 and a p-type GaN contact layer 111 are sequentially stacked. Here, p-type AlGaN
The cap layer 108 is used for growing the p-type GaN optical waveguide layer 109, the p-type AlGaN cladding layer 110, and the p-type GaN contact layer 111 at a temperature of about 1000 ° C.
a _1-x In _x N / Ga _1-y In _y N This is for preventing the decomposition of InN from the active layer 107 having a multiple quantum well structure and for preventing the overflow of electrons from the active layer 107. .

An upper layer portion of the n-type GaN contact layer 104,
n-type AlGaN cladding layer 105, n-type GaN optical waveguide layer _{106, Ga 1-x In x} N / Ga 1-y In y N active layer having a multiple quantum well structure 107, p-type AlGaN cap layer 1
08, the p-type GaN optical waveguide layer 109, the p-type AlGaN cladding layer 110, and the p-type GaN contact layer 111 have a mesa shape having a predetermined width. Also, p in this mesa section
Layer of p-type AlGaN cladding layer 110 and p-type Ga
A ridge 112 having a predetermined width extending in one direction is formed in the N contact layer 111. An insulating film 113 such as a SiO ₂ film is provided on the surface of the mesa portion and the surface of the n-type GaN contact layer 104 other than the mesa portion. The insulating film 112 has an opening 113a above the ridge 112 and an n-type GaN portion adjacent to the mesa.
An opening 113b is provided above the contact layer 104. Further, a p-side electrode 114 is provided so as to straddle the ridge 112, and the opening 11 of the insulating film 113 is formed.
Ohmic contact is made with the p-type GaN contact layer 111 of the ridge 112 through 3a. Further, an n-side electrode 115 is provided on the n-type GaN contact layer 104 through an opening 113b of the insulating film 113 in ohmic contact.

[0007]

When the GaN-based semiconductor laser shown in FIG. 17 is mounted on a submount, the p-side electrode 114 and the n-side electrode 115 of the GaN-based semiconductor laser are It is necessary to connect the side electrode 114 and the n-side electrode 115 to an electrode formed in advance on the submount via solder or the like.

However, during this mounting, the ridge portion 112 of the p-side electrode 114 of the GaN-based semiconductor laser is
Because only the flat part above the sub-mount hits the submount,
The thermal resistance between the p-side electrode 114 and the submount is high, and the stability when the GaN-based semiconductor laser is placed on the submount is poor, and the GaN semiconductor laser is liable to be inclined.

Accordingly, an object of the present invention is to provide a semiconductor light emitting device using a nitride III-V compound semiconductor which can be mounted with high reliability.

[0010]

In order to achieve the above object, the present invention provides a nitride-based III-V compound semiconductor layer for forming a light-emitting device structure on one main surface of a substrate, comprising: In a semiconductor light-emitting element in which a first electrode is formed higher than a second electrode on a system III-V compound semiconductor layer,
A linear projection and a groove on at least one side of the projection are formed above the nitride-based III-V compound semiconductor layer in the formation region of the first electrode. .

In the present invention, the first electrode is typically formed so as to straddle the protrusion and the groove on at least one side of the protrusion. In addition, this groove is preferably formed on both sides of the protrusion in order to increase the area of the flat portion formed at the highest portion of the first electrode. In a typical example, the first electrode is in contact with the nitride-based III-V compound semiconductor layer at the protrusion, and is formed on the nitride-based III-V compound semiconductor layer at a portion other than the protrusion. Is in contact with the insulating film formed on the substrate. In another typical example, the first electrode is formed on the nitride-based III-V compound semiconductor layer of the protrusion, and the first electrode is formed on the nitride-based III-V compound semiconductor layer.
And cover the electrodes and straddle the protrusions and grooves.
Is formed as a part of the electrode. In this case, this pad electrode allows the projection-based nitride III
The first electrode formed on the -V compound semiconductor layer is mechanically protected. Here, typically, the first electrode is p
The second electrode is an n-side electrode.

In the present invention, the nitride III-V compound semiconductor contains at least one group III element selected from the group consisting of Ga, Al, In and B and at least N, and optionally further contains As or It is composed of a group V element containing P, and specific examples include GaN, In
N, AlN, AlGaN, GaInN, AlGaInN
And so on.

According to the present invention configured as described above, the nitride III-V in the region where the first electrode is formed is formed.
Since the linear protrusion and the groove on at least one side of the protrusion are formed on the upper part of the group III compound semiconductor layer, the linear protrusion is formed so as to straddle the protrusion and the groove on at least one side of the protrusion. When one electrode is formed, a flat portion is formed on the first electrode at substantially the same height as the projection and a portion outside the groove on at least one side of the projection. Therefore, this semiconductor light emitting device is
In the case where the first electrode and the second electrode are mounted on the submount with the first electrode and the second electrode facing down, the first electrode can hit the submount in a wider area.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In all the drawings of the embodiments, the same or corresponding portions are denoted by the same reference numerals.

FIG. 1 shows G according to a first embodiment of the present invention.
1 shows an aN-based semiconductor laser. This GaN-based semiconductor laser has a ridge structure and an SCH structure.

As shown in FIG. 1, in the GaN-based semiconductor laser according to the first embodiment, an undoped GaN layer 3, n is formed on a c-plane sapphire substrate 1 via an undoped GaN buffer layer 2 grown at a low temperature. -Type GaN contact layer 4, n-type AlGaN cladding layer 5, n-type GaN
Optical waveguide layer _{6, Ga 1-x In x} N / Ga 1-y In y N active layer 7 of multiple quantum well structure, p-type AlGaN cap layer 8, p-type GaN optical guide layer 9, p-type AlGaN cladding layer 10 And a p-type GaN contact layer 11 are sequentially stacked. Here, when growing the p-type GaN optical waveguide layer 9, the p-type AlGaN cladding layer 10, and the p-type GaN contact layer 11 at a temperature of about 1000 ° C., the p-type AlGaN cap layer 8 is Ga _1-x In _x N / Ga _1-y In _y N
This is for preventing the decomposition of InN from the active layer 7 having the multiple quantum well structure and for preventing the overflow of electrons from the active layer 7.

The undoped GaN buffer layer 2 has a thickness of, for example, 30 nm, and the undoped GaN layer 3 has a thickness of, for example, 1 μm. The n-type GaN contact layer 4 has a thickness of, for example, 4 μm, and is doped with, for example, Si as an n-type impurity. The n-type AlGaN cladding layer 5 has a thickness of, for example, 0.7 μm, and has an n-type impurity of, for example, Si.
Is doped. The n-type GaN optical waveguide layer 6 has a thickness of, for example, 0.1 μm, and is doped with, for example, Si as an n-type impurity. The p-type AlGaN cap layer 8 has a thickness of, for example, 20 nm.
Is doped. The p-type GaN optical waveguide layer 9 has a thickness of, for example, 0.1 μm, and is doped with, for example, Mg as a p-type impurity. The p-type AlGaN cladding layer 10 has a thickness of, for example, 0.7 μm, and is doped with, for example, Mg as a p-type impurity. The Al composition ratio of the n-type AlGaN cladding layer 5 and the p-type AlGaN cladding layer 10 is, for example, 0.07,
The 1 composition ratio is, for example, 0.16. Ga _1-x In _x N /
For the active layer 7 having a Ga _1-y In _y N multiple quantum well structure, for example, x = 0.11, y = 0.01, Ga _1-x In
_x N layer and Ga _1-y In y N layer having a thickness of, for example, respectively 3nm and 6 nm, number of wells is 4.

The upper layer of the n-type GaN contact layer 4, the n-type AlGaN cladding layer 5, the n-type GaN optical waveguide layer 6, the Ga
Active layer 7, p-type AlGaN cap layer 8, p-type GaN optical waveguide layer 9, p-type AlGaN cladding layer 10, and p-type Ga having a _1-x In _x N / Ga _1-y In _y N multiple quantum well structure.
N contact layer 11 has a mesa shape having a predetermined width. The height of the mesa portion is, for example, 2.3 μm, and the width is, for example, 250 to
It is 300 μm. In addition, the p-type Al
The upper layer of the GaN cladding layer 10 and the p-type GaN contact layer 11 are, for example, GaN-based semiconductor <11-20>.
Grooves 12 and 13 extending linearly in parallel with each other in the direction are provided.
4 are formed. The width of each of the grooves 12 and 13 is, for example, 20 nm, and the width of the ridge portion 14 is, for example, 4 μm.
It is. The distance between the groove 12 and one side surface of the mesa portion is, for example, 10 nm. These grooves 12 and 13 have a depth such that the thickness of the p-type AlGaN cladding layer 10 at the bottom thereof is, for example, 0.1 μm.

N of the surface of the mesa portion and portions other than the mesa portion
An insulating film 15 such as a SiO ₂ film is provided on the surface of the type GaN contact layer 4. The thickness of the insulating film 15 is, for example, 0.3 μm. This insulating film 15 has
An opening 15a is provided in a portion above the ridge portion 14, and an opening 15b is provided in a portion adjacent to the mesa portion above the n-type GaN contact layer 4. Further, a p-side electrode 16 is provided so as to straddle the ridge portion 14 and the grooves 12 and 13, and has an ohmic contact with the p-type GaN contact layer 11 of the ridge portion 14 through the opening 15 a of the insulating film 15. In this case, both ends of the p-side electrode 16 substantially coincide with both side surfaces of the mesa portion. The p-side electrode 16 is formed of, for example, a Ni / P film in which a Ni film, a Pt film, and an Au film are sequentially laminated.
t / Au structure, and these Ni film, Pt film and A
The thickness of the u film is, for example, 10 nm, 100 nm, and 300 nm, respectively. Further, an n-side electrode 17 is provided in ohmic contact on the n-type GaN contact layer 4 through the opening 15b of the insulating film 15. The n-side electrode 17 has, for example, a Ti / Al / Pt / Au structure in which a Ti film, an Al film, a Pt film, and an Au film are sequentially laminated, and has a thickness of the Ti film, Al film, Pt film, and Au film. For example, 10 nm, 100 nm, 100 nm, and 3
00 nm.

The resonator length of this GaN-based semiconductor laser is, for example, 1 mm, and the chip width is, for example, 600 μm. In addition, the end face of the resonator is, for example, (11-2) of the GaN-based semiconductor layer.
0) plane. The end face of the resonator is coated with an end face, and the reflectance of the front end face and the end face of the resonator are set to, for example, 64% and 88%, respectively.

Next, a method of manufacturing the GaN-based semiconductor laser according to the first embodiment configured as described above will be described.

In order to manufacture this GaN-based semiconductor laser, first, as shown in FIG. 2, undoped GaN is deposited on a c-plane sapphire substrate 1 at a temperature of, for example, about 560 ° C. by metal organic chemical vapor deposition (MOCVD). After the growth of the buffer layer 2, the undoped GaN layer 3, the n-type GaN contact layer 4, the n-type AlGaN cladding layer 5, the n-type GaN optical waveguide layer 6, Ga _1-x In _x N / G
a _1-y In _y N Active layer 7 with multiple quantum well structure, p-type Al
GaN cap layer 8, p-type GaN optical waveguide layer 9, p-type Al
GaN cladding layer 10 and p-type GaN contact layer 1
1 is grown sequentially. Here, the undoped GaN layer 3, which is a layer containing no In, the n-type GaN contact layer 4, and n
-Type AlGaN cladding layer 5, n-type GaN optical waveguide layer 6, p
-Type AlGaN cap layer 8, p-type GaN optical waveguide layer 9, p-type
The growth temperature of the AlGaN cladding layer 10 and the p-type GaN contact layer 11 is about 1000 ° C., and the active layer 7 has a Ga _1-x In _x N / Ga _1-y In _y N multiple quantum well structure, which is a layer containing In. Has a growth temperature of 700 to 800 ° C. The growth raw materials for these GaN-based semiconductor layers are, for example,
Trimethyl gallium (TMG) is used as a raw material for Ga as a group III element, trimethyl aluminum (TMA) is used as a raw material for Al as a group III element, and trimethyl indium (TM) is used as a raw material for In as a group III element.
MI), and ammonia (NH ₃ ) is used as a raw material of N which is a group V element. As the carrier gas, for example, a mixed gas of hydrogen (H ₂ ) and nitrogen (N ₂ ) is used. As the dopant, for example, monosilane (SiH ₄ ) is used as the n-type dopant, and methylcyclopentadienyl magnesium ((MCp) ₂ Mg) is used as the p-type dopant.

Next, a 0.4 μm-thick SiO ₂ film, for example, is formed on the entire surface of the p-type GaN contact layer 11 by, for example, a CVD method, a vacuum deposition method, a sputtering method, or the like, and then lithography is performed on the SiO ₂ film. To form a resist pattern (not shown) having a predetermined shape, and using this resist pattern as a mask, for example, wet etching using a hydrofluoric acid-based etchant, or CF ₄ or C
The SiO ₂ film is etched by dry etching (RIE or the like) using an etching gas containing fluorine such as HF ₃ . Thereby, as shown in FIG.
Mask 18 made of SiO ₂ film on N contact layer 11
Is formed.

Next, as shown in FIG. 3, etching is performed using the mask 18 by, for example, a reactive ion etching (RIE) method until the n-type GaN contact layer 4 is reached. At this time, for example, the n-type GaN contact layer 4 is etched by 0.5 μm. As an etching gas for this RIE, for example, a chlorine-based gas (Cl ₂ , S
iCl ₄ etc.).

Next, after the mask 18 is removed by etching, an Si film having a thickness of, for example, 0.2 μm is again formed on the entire surface of the substrate by, for example, a CVD method, a vacuum deposition method, or a sputtering method.
After forming the O ₂ film, a resist pattern (not shown) having a predetermined shape is formed on the SiO ₂ film by lithography, and wet etching using, for example, a hydrofluoric acid-based etchant using the resist pattern as a mask, or , Dry etching (RIE or the like) using an etching gas containing fluorine such as CF ₄ or CHF ₃
Etch the O ₂ film. As a result, as shown in FIG. 4, a mask 19 made of a SiO ₂ film is formed on the surface of the substrate including the mesa.

Next, as shown in FIG. 5, the p-type GaN contact layer 11 is
The grooves 12 and 13 are formed by etching to a predetermined depth in the thickness direction of the substrate, and the ridge portion 14 is formed.
As the RIE etching gas, for example, a chlorine-based gas is used.

Next, as shown in FIG. 6, a resist pattern 20 is formed by lithography to cover the surface of the region excluding the n-side electrode formation region.

Next, as shown in FIG. 7, an opening 15b is formed by etching the insulating film 15 using the resist pattern 20 as a mask.

Next, while the resist pattern 20 is left, a Ti film, A
1 film, a Pt film, and an Au film are sequentially formed, and then a resist pattern 20 is formed on the Ti film, the Al film, and the P film.
It is removed together with the t film and the Au film (lift-off). As a result, as shown in FIG.
b, Ti /
An n-side electrode 17 having an Al / Pt / Au structure is formed.

Next, for example, by performing a heat treatment at 800 ° C. for 10 minutes in a nitrogen gas atmosphere, the p-type AlG
aN cap layer 8, p-type GaN optical waveguide layer 9, p-type AlG
aN cladding layer 10 and p-type GaN contact layer 11
Is electrically activated, and an alloying process of the n-side electrode 17 is performed.

Next, as shown in FIG. 9, a resist pattern 21 is formed by lithography to cover the surface of the region other than the region of the ridge portion 14.

Next, as shown in FIG. 10, an opening 15a is formed by etching the insulating film 15 using the resist pattern 21 as a mask, and the upper surface of the ridge portion 14 is exposed.

Next, as shown in FIG. 11, a resist pattern 22 is formed by lithography to cover the surface of the region excluding the p-side electrode formation region.

Next, after a Ni film, a Pt film and an Au film are sequentially formed on the entire surface of the substrate by, for example, a vacuum deposition method, the resist pattern 22 is removed together with the Ni film, the Pt film and the Au film formed thereon. Thereby, as shown in FIG. 1, the p-side electrode 16 having the Ni / Pt / Au structure is formed across the ridge portion 14 and the grooves 12 and 13. Next, for example, at 600 ° C. in a nitrogen gas atmosphere.
The alloy processing of the p-side electrode 16 is performed by performing the heat treatment for 20 minutes.

Thereafter, the c-plane sapphire substrate 1 on which the laser structure is formed as described above is processed into a bar shape to form both resonator end faces, and after the end face coating is performed, the bar is formed into chips. I do. Thus, the intended GaN-based semiconductor laser having the ridge structure and the SCH structure is manufactured.

As described above, according to the first embodiment, the grooves 12, 1 are formed in the p-type GaN contact layer 11 and the p-type AlGaN cladding layer 10 in the p-side electrode formation region.
3 are formed in parallel with each other, and a ridge portion 14 is formed between the grooves 12 and 13.
Since the p-side electrode 16 is formed so as to straddle the grooves 12 and 13, the p-side electrode 16 has a flat portion at a portion corresponding to the ridge portion 14 and a portion outside the grooves 12 and 13. They are formed at substantially the same height. Therefore, the GaN-based semiconductor laser is connected to the p-side electrode 16 and the n-side
When the p-side electrode 16 is mounted on, for example, a submount of a can package with the side electrode 17 facing down, the p-side electrode 16 hits the submount at a flat portion thereof, and thus hits the submount with a sufficiently larger area than before. This reduces the thermal resistance between the p-side electrode 16 and the submount, and
Since the stability when the GaN-based semiconductor laser is placed on the submount becomes good and the inclination hardly occurs,
The reliability of mounting can be improved as compared with the related art.

FIG. 12 shows a GaN-based semiconductor laser according to a second embodiment of the present invention. This GaN-based semiconductor laser also has a ridge structure and an SCH structure.

As shown in FIG. 12, in the GaN-based semiconductor laser according to the second embodiment, a p-side electrode 16 is provided on the p-type GaN contact layer 11 of the ridge portion 14 through the opening 15a of the insulating film 15. , This p-side electrode 1
6, a pad electrode 23 is provided over the ridge portion 14 and the grooves 12, 13. The pad electrode 23 is electrically connected to the p-side electrode 16,
Acts as part of the side electrode. A pad electrode 24 is also provided on the n-side electrode 17. These pad electrodes 2
Reference numerals 3 and 24 each have, for example, a Ti / Au structure in which a Ti film and an Au film are sequentially stacked, and the thicknesses of the Ti film and the Au film are, for example, 50 nm and 450 nm, respectively. The other points are the same as those of the GaN-based semiconductor laser according to the first embodiment, and the description is omitted.

Next, a method of manufacturing the GaN-based semiconductor laser according to the second embodiment configured as described above will be described.

In order to manufacture this GaN-based semiconductor laser, first, the process is advanced to the step shown in FIG. 8 in the same manner as in the GaN-based semiconductor laser according to the first embodiment.
As shown in FIG. 13, the ridge portion 1 is formed by lithography.
Resist pattern 2 covering the surface of the region excluding region 4
5 is formed.

Next, as shown in FIG. 14, an opening 15a is formed by etching the insulating film 15 using the resist pattern 25 as a mask, and the upper surface of the ridge portion 14 is exposed.

Next, while the resist pattern 25 is left, an Ni film, a P
After sequentially forming the t film and the Au film, the resist pattern 25 is removed together with the Ni film, the Pt film, and the Au film formed thereon. Thereby, as shown in FIG. 15, the p of the ridge 14 at the opening 15a of the insulating film 15 is formed.
A p-side electrode 16 having a Ni / Pt / Au structure is formed on the type GaN contact layer 11.

Next, as shown in FIG. 16, a resist pattern 26 is formed by lithography to cover the surface of the region excluding the pad electrode formation region.

Next, a Ti film and an Au film are sequentially formed on the entire surface of the substrate by, for example, a vacuum evaporation method while leaving the resist pattern 26, and then the resist pattern 26 is formed on the Ti film and the Au film formed thereon. Together with it. As a result, as shown in FIG.
Pad electrode 23 is formed over ridge portion 14 and trenches 12 and 13 so as to cover n-side electrode 1.
A pad electrode 24 is formed on 7.

Thereafter, the process is advanced in the same manner as in the first embodiment to manufacture a target GaN-based semiconductor laser.

According to the second embodiment, the same advantages as those of the first embodiment can be obtained.
Since the pad electrode 23 is provided so as to cover the ridge portion 14 and the grooves 12 and 13 so as to cover the p-type electrode 6, the mechanical strength of the p-side electrode 16 formed in a strip shape can be improved. The advantage that the reliability and the manufacturing yield of the GaN-based semiconductor laser can be improved can also be obtained.

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

For example, the numerical values, structures, raw materials, processes, and the like described in the first and second embodiments are merely examples, and different numerical values, structures, raw materials, processes, and the like may be used as necessary. May be used.

[0049]

As described above, according to the present invention, the nitride III-V in the region where the first electrode is formed is formed.
Since the linear projection and the groove on at least one side of the projection are formed on the group III compound semiconductor layer, the semiconductor light emitting device can be mounted with high reliability.

[Brief description of the drawings]

FIG. 1 is a sectional view of a GaN-based semiconductor laser according to a first embodiment of the present invention, which is perpendicular to the cavity length direction.

FIG. 2 is a cross-sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 3 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

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

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

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

FIG. 8 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 9 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 10 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 11 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the first embodiment of the present invention.

FIG. 12 is a sectional view of a GaN-based semiconductor laser according to a second embodiment of the present invention, which is perpendicular to the cavity length direction.

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

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

FIG. 15 is a sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the second embodiment of the present invention.

FIG. 16 is a cross-sectional view for explaining the method for manufacturing the GaN-based semiconductor laser according to the second embodiment of the present invention.

FIG. 17 is a sectional view showing a conventional GaN-based semiconductor laser.

[Explanation of symbols]

1 ... c-plane sapphire substrate, 4 ... n-type GaN contact layer, 5 ... n-type AlGaN cladding layer, 6 ...
-N-type GaN optical waveguide layer, 7 ... active layer, 8 ... p-type AlGaN cap layer, 9 ... p-type GaN optical waveguide layer,
10 ... p-type AlGaN cladding layer, 11 ... p-type GaN contact layer, 12, 13 ... groove, 14 ...
Ridge part, 15: insulating film, 16: p-side electrode, 1
7 n-side electrode, 23, 24 pad electrode

Claims (6)

[Claims] 1. A nitride-based III-V compound semiconductor layer forming a light-emitting device structure is formed on one main surface of a substrate, and a first electrode is formed on the nitride-based III-V compound semiconductor layer. In the semiconductor light emitting device formed higher than the second electrode, the nitride III in the formation region of the first electrode
-A semiconductor light emitting device wherein a linear protrusion and a groove on at least one side of the protrusion are formed on the upper part of the group V compound semiconductor layer. 2. The semiconductor light emitting device according to claim 1, wherein said first electrode is formed so as to straddle said protrusion and said groove. 3. The semiconductor light emitting device according to claim 1, wherein said groove is formed on both sides of said projection. 4. The first electrode is in contact with the nitride-based III-V compound semiconductor layer of the protrusion, and the nitride-based III-V compound semiconductor layer is provided at a portion other than the protrusion. 2. The semiconductor light emitting device according to claim 1, wherein said semiconductor light emitting device is in contact with an insulating film formed thereon. 5. The semiconductor device according to claim 5, wherein the first electrode is formed on the nitride-based III-V compound semiconductor layer of the projection, and covers the first electrode, and the projection and the groove are formed. 2. A pad electrode constituting a part of the first electrode so as to cross over the first electrode.
The semiconductor light-emitting device according to claim 1. 6. The method according to claim 1, wherein the first electrode is a p-side electrode, and the second electrode is an n-side electrode.
The semiconductor light-emitting device according to claim 1.