JP2002223039A - Semiconductor light emitting element and method for manufacturing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light emitting element which can reduce a shock or damage to a ridge participating in a light emitting operation. SOLUTION: The semiconductor light emitting element is provided with ridges (8a, 9a) formed on the surface of a p-type etching stop layer 7, and dummy ridges (8b, 9b) which are formed by keeping a prescribed interval from the ridges (8a, 9a) and which comprise a side edge (side-face upper end) in the longitudinal direction not parallel to the side edge (side-face upper end) in the longitudinal direction of the ridges (8a, 9a).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor light emitting device and a method for manufacturing the same, and more particularly, to a semiconductor light emitting device having a ridge portion and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, semiconductor light emitting devices such as semiconductor lasers have been widely used as light sources for optical communication, consumer use, and industrial equipment. Then, in order to obtain a high-output semiconductor light emitting device, it is necessary to minimize absorption loss of light generated in the active layer. In order to reduce the light absorption loss, it is preferable to make the thickness (height) of the ridge portion made of the cladding layer that does not absorb light as large as possible. For this reason, conventionally, a semiconductor light emitting element having an inverted mesa-shaped (reverse trapezoidal) ridge portion capable of making the ridge portion higher than a normal mesa shape (trapezoidal shape) is often used. A semiconductor light emitting device having an inverted mesa-shaped ridge is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 5-21902.

FIG. 10 shows a conventional semiconductor light emitting device (semiconductor laser) disclosed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 5-21902.
FIG. 3 is a cross-sectional view showing the structure of FIG. Referring to FIG. 10, in this conventional semiconductor light emitting device, an n-type cladding layer 102 made of n-type AlGaAs and an active layer 103 are formed on an n-type GaAs substrate 101. On the active layer 103, a p-type cladding layer 104 made of p-type AlGaAs having an inverted mesa-shaped ridge is formed. On the upper surface of the ridge portion of the p-type cladding layer 104, p-type GaAs
A p-type ohmic contact layer 105 is formed. The current blocking layer 10 made of n-type GaAs is embedded so as to bury the ridge portion made up of the p-type cladding layer 104 and the p-type ohmic contact layer 105 and to expose the upper surface of the p-type ohmic contact layer 105.
7 are formed. On the p-type ohmic contact layer 105 and the current blocking layer 107 exposed on the upper surface of the ridge portion
A p-type electrode 109 is formed thereon. On the back surface of the n-type GaAs substrate 101, an n-type electrode 108 is formed.

FIGS. 11 to 13 are cross-sectional views for explaining a manufacturing process of the conventional semiconductor light emitting device shown in FIG. With reference to FIGS. 10 to 13, a description will be given of a manufacturing process of a conventional semiconductor light emitting device.

[0005] First, as shown in FIG.
On the substrate 101, MOCVD (Metal Organ)
ic Chemical Vapor Deposit
Using an ion) method, an n-type cladding layer 102 made of n-type AlGaAs, an active layer 103, a p-type cladding layer 104 made of p-type AlGaAs, and a p-type ohmic contact layer 105 made of p-type GaAs are continuously formed. Let it grow. Thereafter, a stripe-shaped S having a thickness of several μm is formed in a predetermined region on the p-type ohmic contact layer 105.
A mask layer 110 made of iO ₂ is formed.

[0006] Next, as shown in FIG.
By etching the p-type cladding layer 104 and the p-type ohmic contact layer 105 using 0 as a mask, a stripe-shaped inverted mesa ridge portion composed of the p-type cladding layer 104 and the p-type ohmic contact layer 105 is formed.

Then, using the mask layer 110 as a selective growth mask, a current blocking layer 107 made of n-type GaAs as shown in FIG. 13 is formed by MOCVD. At this time, the current blocking layer 107 is not grown on the mask layer 110 made of SiO ₂ , but is formed on the p-type cladding layer 1.
It is formed so as to completely bury the side surface of the ridge portion composed of the semiconductor device 04 and the p-type ohmic contact layer 105. After that, the mask layer 110 is removed.

[0010] Finally, as shown in FIG. 10, a p-type electrode 109 is formed on the p-type ohmic contact layer 105 and the current blocking layer 107 exposed on the upper surface of the ridge. Further, on the back surface of the n-type GaAs substrate 101, an n-type electrode 108 is formed. Thus, a conventional semiconductor light emitting device is formed.

[0009]

As described above, in the conventional semiconductor light emitting device, the p-type clad layer 104 and the p-type
By etching the ohmic contact layer 105, a ridge having an inverted mesa shape was formed. In this case, after the formation of the ridge, only the ridge protrudes from the element surface until the current blocking layer 107 is formed so as to fill the ridge in the next step. Conventionally, there has been a problem that the ridge portion is susceptible to impact or damage while only the ridge portion protrudes.

[0010] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide:
An object of the present invention is to provide a semiconductor light emitting device capable of reducing impact and damage to a ridge portion involved in light emission.

Another object of the present invention is to provide a method for manufacturing a semiconductor light emitting device capable of reducing impact and damage to a ridge portion involved in light emission.

[0012]

A semiconductor light emitting device according to one aspect of the present invention includes a semiconductor layer including an active layer, a ridge formed on a surface of the semiconductor layer, and a predetermined distance from the ridge. And a dummy ridge having a longitudinal side edge that is not parallel to the longitudinal side edge of the ridge portion.

In the semiconductor light emitting device according to this aspect,
As described above, by providing the dummy ridge portion,
Since the ridge portion and the dummy ridge portion have a protruding shape, it is possible to reduce the impact and damage to the ridge portion as compared with the shape where only the ridge portion protrudes. Also,
By providing a dummy ridge portion having a longitudinal side edge not parallel to the longitudinal side edge of the ridge portion, for example, when the longitudinal side edge of the ridge portion is formed in the [011] direction In addition, the current blocking layer can be sufficiently grown on the side edges in the longitudinal direction of the dummy ridge portion that is not parallel to the dummy ridge portion. Thereby, it is possible to effectively prevent the occurrence of a leak current.

In the semiconductor light emitting device according to the above aspect, preferably, the longitudinal side edge of the ridge portion is formed in a crystal direction which becomes an inverted mesa shape when etched and in a direction which becomes an optical axis direction. The longitudinal side edge of the dummy ridge is formed in a direction that is not parallel to the direction of the longitudinal side edge of the ridge. With this configuration, the current blocking layer can easily be sufficiently grown on the side edges in the longitudinal direction of the dummy ridge portion. Also,
Preferably, the ridge portion and the dummy ridge portion include Ga and As, and a side edge in a longitudinal direction of the ridge portion is [01].
1] direction, and the side edges in the longitudinal direction of the dummy ridge are formed in a direction that is not parallel to the [011] direction. Even with such a configuration, the current blocking layer can be easily grown sufficiently on the longitudinal side edge of the dummy ridge.

In the above case, it is preferable to further include a current blocking layer formed so as to cover the whole of the dummy ridge portion other than the ridge portion. According to this structure, since only the ridge portion is formed so as not to be covered with the current blocking layer, current can be easily supplied only to the ridge portion.

In the above case, it is preferable to further include a contact layer formed so as not to contact the dummy ridge portion but to contact only the ridge portion. With this configuration, it is possible to easily supply a current only to the ridge portion via the contact layer.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor light emitting device, comprising: forming a semiconductor layer including an active layer; forming a resist film in a predetermined region on the surface of the semiconductor layer; Forming a ridge portion and a dummy ridge portion having a longitudinal side edge that is not parallel to the longitudinal side edge of the ridge portion by etching the semiconductor layer with the mask as a mask.

In the method of manufacturing a semiconductor light emitting device according to another aspect, as described above, the dummy ridge is formed at a predetermined interval from the ridge, so that the ridge and the dummy ridge have a protruding shape. Therefore, the impact and damage to the ridge portion can be reduced as compared with the shape in which only the ridge portion protrudes. Further, by providing a dummy ridge portion having a longitudinal side edge that is not parallel to the longitudinal side edge of the ridge portion, for example, the longitudinal side edge of the ridge portion is formed in the [011] direction. In this case, the current blocking layer can be sufficiently grown on the longitudinal side edge of the dummy ridge portion that is not parallel thereto. This makes it possible to easily form a semiconductor light emitting device that can effectively prevent the occurrence of a leak current.

In the method for manufacturing a semiconductor light emitting device according to the above another aspect, preferably, the side edge in the longitudinal direction of the ridge portion is a crystal direction which becomes an inverted mesa shape when etched and a direction which becomes an optical axis direction. And the longitudinal side edge of the dummy ridge portion is formed in a direction that is not parallel to the direction of the longitudinal side edge portion of the ridge portion. With this configuration, the current blocking layer can easily be sufficiently grown on the side edges in the longitudinal direction of the dummy ridge portion.

In the above case, preferably, the ridge portion and the dummy ridge portion include Ga and As, and a longitudinal side edge of the ridge portion is formed parallel to the [011] direction. The longitudinal side edge of the part is [01
1] The direction is not parallel to the direction. Even with such a configuration, the current blocking layer can be easily grown sufficiently on the longitudinal side edge of the dummy ridge.

In this case, preferably, the step of forming a resist film includes a step of forming a first resist film parallel to the [011] direction and a second resist film not parallel to the [011] direction. Forming the first portion and the dummy ridge portion by etching the semiconductor layer using the first resist film and the second resist film as a mask;
Forming a ridge portion parallel to the [011] direction and a dummy ridge portion not parallel to the [011] direction. With this configuration, a ridge portion parallel to the [011] direction and a dummy ridge portion not parallel to the [011] direction can be easily formed.

In the above case, it is preferable that the method further comprises a step of growing a current blocking layer so as to cover the entire dummy ridge portion. With this configuration, it is possible to easily supply current only to the ridge portion without flowing current to the dummy ridge portion.

In the above case, preferably, in the step of forming the current blocking layer, the current blocking layer is grown so as to cover the ridge portion and the dummy ridge portion, and then the current blocking layer located on the ridge portion is removed. Forming an opening on the ridge. With this configuration, it is possible to easily supply current only to the ridge portion through the opening on the ridge portion.

In the above case, it is preferable that the method further comprises a step of forming a contact layer so as to contact only the ridge portion without contacting the dummy ridge portion. With this configuration, it is possible to easily supply current only to the ridge portion via the contact layer.

[0025]

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

FIG. 1 is a sectional view showing the structure of a semiconductor light emitting device (semiconductor laser) according to one embodiment of the present invention.

First, the structure of a semiconductor light emitting device (semiconductor laser) according to one embodiment will be described with reference to FIG. In the semiconductor light emitting device according to this embodiment, about 90
about 2.5 μm on an n-type GaAs substrate 1 having a thickness of μm.
n-type cladding layer 2 made of n-type AlGaAs having a thickness of μm, n-type AlGa having a thickness of about 0.05 μm
N-type carrier block layer 3 made of As and active layer 4
Are formed. This active layer 4 has a thickness of about 0.008 μm.
A well layer made of AlGaAs having a thickness of about 0.1 mm.
A guide layer made of AlGaAs having a thickness of about 018 μm, and an AlGa layer having a thickness of about 0.008 μm
It has a structure in which barrier layers made of As are stacked. A p-type AlG having a thickness of about 0.05 μm is formed on the active layer 4.
a-type p-type carrier blocking layer 5, about 0.13
p-type first layer made of p-type AlGaAs having a thickness of μm
A cladding layer 6 and a p-type etching stop layer 7 of p-type AlGaAs having a thickness of about 0.02 μm
Are formed.

Here, in the present embodiment, a p-type second layer made of p-type AlGaAs is formed on the p-type etching stop layer 7.
An inverted mesa-shaped ridge portion formed by the cladding layer 8a and the p-type cap layer 9a made of p-type GaAs is formed. The longitudinal side edge (upper end of the side surface) of the ridge portion is formed in the [011] direction which is the crystal direction in which the ridge portion has an inverted mesa shape during etching and is the optical axis direction of the laser. . The p-type second cladding layer 8b made of p-type AlGaAs is sandwiched between the ridge portion and the ridge portion located at the center at a predetermined distance.
And a p-type cap layer 9b made of p-type GaAs to form a dummy ridge portion. The longitudinal side edge (upper side end) of the dummy ridge is
It is formed in a direction that is not parallel to the [011] direction.

The left and right dummy ridge portions (8
n-type AlGaAs having a thickness of about 1.0 μm so as to cover the entire surface including the upper surface, side surfaces, and side edges of (b, 9b) and to expose only the upper surface of the central ridge portion (8a, 9a). Is formed.

A p-type GaAs having a thickness of about 6.0 μm covers the current blocking layer 10 and contacts the p-type cap layer 9a on the upper surface of the central ridge.
A p-type contact layer 11 made of s is formed.

The n-type cladding layer 2, the n-type carrier blocking layer 3, the active layer 4, the p-type carrier blocking layer 5,
First cladding layer 6 and p-type etching stop layer 7
Is an example of the “semiconductor layer including the active layer” of the present invention.
The p-type contact layer 11 is an example of the “contact layer” of the present invention.

The current path of the semiconductor light emitting device of the present embodiment having the above-described structure includes the p-type contact layer 1
A current flows from the portion located on the ridge portion 1 to the active layer 4 via the p-type cap layer 9a and the p-type second cladding layer 8a constituting the ridge portion. Thereby, laser light can be generated in the region of the active layer 4 located below the ridge portion. In addition, the upper surface, side surface, and side edge portion of the dummy ridge portion located on the left and right (upper end of the side surface)
Is sufficiently covered by the current blocking layer 10,
No current flows through the p-type cap layer 9b constituting the dummy ridge portion. Therefore, no laser light is generated in the region of the active layer 4 below the dummy ridge portion. That is, only the ridge located at the center is involved in light emission.

In this embodiment, as described above, the dummy ridge portion is provided so as to sandwich the ridge portion at a predetermined interval from the ridge portion, so that the ridge portion and the dummy ridge portion have a protruding shape. Therefore, the impact and damage to the ridge portion can be reduced as compared with the shape in which only the ridge portion protrudes.

In the present embodiment, as described above, the dummy ridges whose side edges are not parallel to the [011] direction are provided by providing the dummy ridges whose side edges in the longitudinal direction are not parallel to the [011] direction. Unlike the case where the portion is provided, the current blocking layer 10 can be sufficiently grown on the dummy ridge portion in a manufacturing process described later. This allows
Leakage current can be effectively prevented.

2 to 8 are a sectional view and a plan view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. Next, a manufacturing process of the semiconductor light emitting device according to the embodiment will be described with reference to FIGS.

First, as shown in FIG. 2, an n-type AlGaAs is formed on an n-type GaAs substrate 1 by MOCVD or the like.
n-type cladding layer 2 of s, n-type carrier block layer 3 of n-type AlGaAs, active layer 4, p-type AlGa
P-type carrier block layer 5 made of As, p-type AlGa
P-type first cladding layer 6 made of As, p-type AlGaAs
P-type etching stop layer 7 made of p-type AlGaAs
s p-type second cladding layer 8 and p-type GaAs
The p-type cap layer 9 made of s is continuously grown.

Thereafter, as shown in FIG. 3, a stripe-shaped resist film 12a is formed in a predetermined region on the p-type cap layer 9.
And 12b.

Here, in this embodiment, as shown in FIG. 4, the longitudinal side edge of the resist film 12a at the center is formed by G
It is formed in the [011] direction, which is the direction of the inverted mesa ridge of aAs (the direction in which the ridge portion becomes an inverted mesa shape during etching) and is the optical axis direction of the laser. Further, the side edges in the longitudinal direction of the left and right resist films 12b are formed in a direction inclined by a predetermined angle θ (30 ° in the present embodiment) from the [011] direction. In FIG. 4, the chip dividing line is
This indicates a dividing line when a chip is formed after the completion of the wafer process.

Next, using the resist films 12a and 12b shown in FIGS. 3 and 4 as a mask, the p-type second cladding layer 8 and the p-type cap layer 9 are wet-etched with a tartaric acid-based etchant. 5, a p-type second cladding layer 8a and a p-type cap layer 9
a) a ridge portion having an inverted mesa shape and a p-type second
The left and right dummy ridge portions composed of the cladding layer 8b and the p-type cap layer 9b are formed. In this case, FIG.
As shown in (1), the longitudinal side edge (upper end of the side surface) of the central ridge is formed in the [011] direction. On the other hand, the longitudinal side edges (upper end portions of the side surfaces) of the dummy ridge portions located on the left and right are formed in a direction inclined by 30 ° from the [011] direction. In the above-described wet etching process for forming the ridge portion and the dummy ridge portion, the p-type etching stop layer 7 functions as an etching stopper. After forming the ridge portion and the dummy ridge portion in this manner, the resist films 12a and 1
2b is removed.

Next, as shown in FIG. 7, a current blocking layer 10 made of n-type AlGaAs is grown so as to cover the p-type etching stop layer 7, the ridge portion, and the dummy ridge portion. At this time, the current blocking layer 10 has sufficient longitudinal edges of the dummy ridge portions not parallel to the [011] direction, so that not only the side and top surfaces of the dummy ridge portions but also the side edges (upper end portions of the side surfaces) are sufficient. To grow. In addition, since the longitudinal side edges of the central ridge are parallel to the [011] direction, the current blocking layer 10 grows on the longitudinal side edges (upper side edges) of the central ridge. Instead, it grows so as to cover portions other than the side edges of the ridge portion.

Here, referring to FIG. 9, as a comparative example of the present embodiment, the side edges in the longitudinal direction of the dummy ridge are
An example formed in parallel to the [011] direction will be described.
As shown in FIG. 9, the current blocking layer 20 does not grow on the longitudinal side edge (upper end of the side surface) of the dummy ridge portion parallel to the [011] direction. For this reason, the side edges in the longitudinal direction of the dummy ridge portion are in contact with the p-type GaAs contact layer 21. As a result, when a dummy ridge portion parallel to the [011] direction is formed, the p-type GaAs contact layer 21 is formed.
Therefore, there is an inconvenience that a leak current occurs in the direction indicated by the arrow through the longitudinal side edge of the dummy ridge.

Therefore, in the present embodiment, as described above,
The side edges in the longitudinal direction of the dummy ridge portion are formed so as not to be parallel to the [011] direction (inclined by 30 °). Thereby, as shown in FIG. 7, the current blocking layer 10 can be sufficiently grown even at the side edge of the dummy ridge portion, and as a result, the occurrence of a leak current can be effectively prevented. .

Thereafter, in a predetermined region on the current blocking layer 10,
A resist film 13 is formed. Then, using the resist film 13 as a mask, the current blocking layer 10 formed on the upper surface of the central ridge portion is removed by etching, and then the resist film 13 is removed. Thereby, as shown in FIG.
Only the upper surface (p-type cap layer 9a) of the central ridge portion is exposed, and a shape in which the entirety of the right and left dummy ridge portions is covered with the current blocking layer 10 is obtained.

Finally, as shown in FIG. 1, a p-type contact layer made of p-type GaAs covers the current blocking layer 10 and contacts the p-type cap layer 9a on the upper surface of the central ridge. 11 is formed. Thus, the semiconductor light emitting device of the present embodiment is formed.

In the manufacturing process of this embodiment, as described above, by forming the dummy ridge at a predetermined distance from the ridge, the ridge and the dummy ridge have a protruding shape. Shock and damage to the ridge portion can be reduced as compared with the shape in which only the protrusion protrudes.

Further, the semiconductor light emitting device of this embodiment can obtain a fundamental transverse mode light output of 150 mW or more at a horizontal spread angle of 8 ° and a 50 ° C at 60 ° C. and 130 mW.
It operated stably for more than 0 hours.

It should be noted that the embodiment disclosed this time is an example in all respects and is not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description of the embodiments, and includes all modifications within the scope and meaning equivalent to the terms of the claims.

For example, in the above embodiment, in the ridge portion containing GaAs, the longitudinal side edge of the ridge portion is formed in the [011] direction which is the reverse mesa ridge direction of GaAs and the optical axis direction of the laser. In addition, the example has been shown in which the side edges in the longitudinal direction of the dummy ridge portion are formed in a direction that is not parallel to the [011] direction. However, the present invention is not limited to this, and is applicable to a ridge portion made of another semiconductor material. It is possible. In this case, the longitudinal side edge of the ridge portion is formed in the direction opposite to the optical axis direction, which is the reverse mesa ridge direction of the semiconductor material constituting the ridge portion, and the longitudinal side edge portion of the dummy ridge portion is formed. Is formed in a direction that is the reverse mesa ridge direction of the semiconductor material and is not parallel to the direction that is the optical axis direction, the same effect can be obtained.

In the above embodiment, the longitudinal side edge of the dummy ridge portion is formed in a direction inclined by 30 ° from the longitudinal side edge of the central ridge portion involved in light emission. The invention is not limited to this, and other angles may be used.
In this case, it is preferable to form in the direction inclined in the range of 0.2 ° to 89.8 °, more preferably 30 °.
What is necessary is just to form in the range of 60 degrees.

In the above-described embodiment, two dummy ridges are provided. However, the present invention is not limited to this, and only one dummy ridge may be provided, or three or more dummy ridges may be provided. .

[0051]

As described above, according to the present invention, it is possible to provide a semiconductor light emitting device capable of reducing impact and damage to a ridge portion involved in light emission and a method of manufacturing the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a semiconductor light emitting device according to an embodiment of the present invention.

FIG. 2 is a sectional view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 3 is a sectional view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 4 is a plan view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 5 is a sectional view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 6 is a plan view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 7 is a cross-sectional view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 8 is a cross-sectional view for explaining a manufacturing process of the semiconductor light emitting device according to the embodiment shown in FIG.

FIG. 9 is a sectional view showing a comparative example of the semiconductor light emitting device according to the embodiment shown in FIG. 1;

FIG. 10 is a sectional view showing a conventional semiconductor light emitting device.

FIG. 11 is a cross-sectional view for explaining a manufacturing process of a conventional semiconductor light emitting device.

FIG. 12 is a cross-sectional view for explaining a manufacturing process of a conventional semiconductor light emitting device.

FIG. 13 is a cross-sectional view for explaining a manufacturing process of a conventional semiconductor light emitting device.

[Explanation of symbols]

 Reference Signs List 1 n-type GaAs substrate (semiconductor layer) 2 n-type cladding layer (semiconductor layer) 3 n-type carrier block layer (semiconductor layer) 4 active layer (semiconductor layer) 5 p-type carrier block layer (semiconductor layer) 6 p-type first Cladding layer (semiconductor layer) 7 p-type etching stop layer (semiconductor layer) 8a, 8bp p-type second cladding layer (semiconductor layer) 9a, 9b p-type cap layer (semiconductor layer) 8a, 9a Ridge portion 8b, 9b dummy ridge Part 10 current blocking layer 11 p-type contact layer (contact layer) 12a, 12b resist film

Claims (12)

[Claims] A semiconductor layer including an active layer; a ridge formed on a surface of the semiconductor layer; a ridge formed at a predetermined distance from the ridge, and a side edge in a longitudinal direction of the ridge. A dummy ridge having non-parallel longitudinal side edges. 2. A longitudinal edge of the ridge portion is formed in a crystal direction which becomes an inverted mesa shape when etched and in a direction which becomes an optical axis direction, and a longitudinal direction of the dummy ridge portion is formed. 2. The semiconductor light emitting device according to claim 1, wherein the side edge portion is formed in a direction that is not parallel to the direction of the side edge portion in the longitudinal direction of the ridge portion. 3. The ridge portion and the dummy ridge portion include Ga and As, and a longitudinal side edge of the ridge portion is formed parallel to a [011] direction. The side edges in the longitudinal direction of [011]
The semiconductor light emitting device according to claim 1, wherein the semiconductor light emitting device is formed in a direction that is not parallel to the direction. 4. The semiconductor light emitting device according to claim 1, further comprising a current blocking layer formed so as to cover the whole of said dummy ridge portion other than said ridge portion. 5. The semiconductor light emitting device according to claim 1, further comprising a contact layer formed so as not to contact said dummy ridge portion but to contact only said ridge portion. . 6. A step of forming a semiconductor layer including an active layer, a step of forming a resist film in a predetermined region on the surface of the semiconductor layer, and etching the semiconductor layer using the resist film as a mask. Forming a ridge portion and a dummy ridge portion having a longitudinal side edge that is not parallel to the longitudinal side edge of the ridge portion. 7. A longitudinal direction edge of the ridge portion is formed in a crystal direction which becomes an inverted mesa shape when etched and in a direction which becomes an optical axis direction, and a side of the dummy ridge portion in a longitudinal direction. The method according to claim 6, wherein the edge is formed in a direction that is not parallel to a direction of a side edge in a longitudinal direction of the ridge. 8. The ridge portion and the dummy ridge portion include Ga and As, and a side edge in a longitudinal direction of the ridge portion is formed parallel to a [011] direction, and a longitudinal edge of the dummy ridge portion is formed. Side edges in the direction [011]
8. Formed in a direction which is not parallel to the direction.
3. The method for manufacturing a semiconductor light emitting device according to item 1. 9. The step of forming the resist film includes the steps of: forming a first resist film parallel to the [011] direction;
1] a step of forming a second resist film not parallel to the direction; and the step of forming the ridge portion and the dummy ridge portion includes forming the semiconductor layer using the first resist film and the second resist film as a mask. 9. The method for manufacturing a semiconductor light emitting device according to claim 8, comprising a step of forming a ridge portion parallel to the [011] direction and a dummy ridge portion not parallel to the [011] direction by etching. 10. The method for manufacturing a semiconductor light emitting device according to claim 6, further comprising a step of growing a current blocking layer so as to cover the entirety of said dummy ridge portion. 11. The step of forming the current blocking layer comprises growing the current blocking layer so as to cover the ridge portion and the dummy ridge portion, and then removing the current blocking layer located on the ridge portion. The method for manufacturing a semiconductor light emitting device according to claim 6, further comprising a step of forming an opening on the ridge. 12. The semiconductor light emitting device according to claim 6, further comprising a step of forming a contact layer so as to contact only said ridge portion without contacting said dummy ridge portion. Device manufacturing method.