JPH11154765A - Semiconductor substrate and luminous element made of gallium nitride-based compound semiconductor, and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize good reliability along with a small driving voltage, by forming a luminous element using a semiconductor with high crystallinity, and reducing contact resistance of an electrode. SOLUTION: A semiconductor luminous element made of gallium nitride-based compound semiconductor has an n-type GaN layer 3 on a substrate 1. A selective growth region 15 and a non-selective growth region are formed on the n-type GaN layer 3. In the selective growth region 15, a laminated structure body 51 is formed on the n-type GaN layer 3. The laminated structural body 51 includes a pair of clad layers 6 and 8 made of gallium nitride-based compound semiconductor layer and an active layer 7. In the non-selective growth region, an n-type Inx Ga1-x N layer 4, where 0<x<=1, and an n-type electrode are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gallium nitride compound semiconductor substrate, a gallium nitride compound semiconductor light emitting device capable of emitting light in a blue region to an ultraviolet region using the substrate, and a method of manufacturing the same. The present invention relates to a gallium nitride-based compound semiconductor light emitting device that can be manufactured by a simple method that does not require a method, and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 1 is a schematic cross-sectional view of a conventional gallium nitride-based compound semiconductor light emitting device manufactured by using a selective growth method.
It is shown in FIG. The conventional technology for producing this light emitting element is as follows.
As a first growth step, n is placed on the sapphire substrate 100.
Type GaN low-temperature buffer layer 110 of 0.01 to 0.2 μm
Form. The sapphire substrate 100 is taken out from the growth apparatus, and an oxide film 210 for selective growth is formed on the n-type GaN low-temperature buffer layer 110. Oxide film 21 for selective growth
0 is etched to form the selective growth region 200. FIG. 11A shows the gallium nitride-based compound semiconductor light emitting device manufactured through the above steps.

Next, the sapphire substrate 100 is introduced into a growth apparatus, and the n-type GaN low-temperature buffer layer 110 is monocrystallized at a substrate temperature of 900 to 1200 ° C.
0, n-type AlGaN cladding layer 130, non-doped or p-type or n-type InGaN active layer 140, p-type A
lGaN cladding layer 150, p-type GaN cap layer 16
0 is sequentially crystal-grown. Thereafter, the oxide film 21 for selective growth is formed.
0 is removed, an n-type electrode 170 is formed on the n-type GaN low-temperature buffer layer 110, and the p-type GaN cap layer 1
A p-type electrode 180 is formed on 60. The nitride-based compound semiconductor light-emitting device manufactured by the steps described above is shown in FIG.
(B). A nitride-based compound semiconductor light-emitting device having the above structure is disclosed in Japanese Patent Application Laid-Open No. 8-255929.

[0004]

However, in the conventional semiconductor light emitting device, a semiconductor layer such as the n-type GaN layer 120, which is to be laminated on the selective growth region 200, is grown again on the n-type GaN low-temperature buffer layer 110 at a high temperature. However, only a semiconductor layer having many crystal defects was obtained. This is because the formation of the oxide film 210 for selective growth such as SiO ₂ for selective growth and the etching of the oxide film 210 for selective growth such as SiO _{2 in the} selective growth region 200 are performed to etch the regrown surface. This is because pits are generated, the surface is roughened, and residual impurities in the air are attached. It is difficult to stack a laminated structure having good crystallinity on the surface from which the selective growth oxide film 210 such as SiO ₂ has been removed by the conventional technique, and the driving voltage of the light emitting device manufactured by the conventional technique is difficult. However, there is a problem that the size becomes larger.

Further, the n-type electrode 170 of the gallium nitride based semiconductor light emitting device using the conventional selective growth method is an n-type G
Since the oxide film 210 for selective growth such as SiO ₂ formed on the aN layer 120 is formed on the etched surface, the contact resistance between the n-type electrode 170 and the n-type GaN layer 120 is large. There is also a problem that only a high value can be obtained when the driving voltage of the element is 4 to 5 V.

Accordingly, an object of the present invention is to provide a highly reliable gallium nitride-based compound semiconductor light emitting device which is made of a good crystalline semiconductor, has a low driving voltage by reducing the contact resistance of the electrode, and has high reliability. Is to provide a way.

[0007]

The gallium nitride-based compound semiconductor substrate of the present invention comprises an n-type GaN layer, an n-type In
_x Ga _1-x N (0 <x ≦ 1) layer, and the n-type In _x G
The a _1-x N (0 <x ≦ 1) layer is a surface protective layer. In the present invention, using the n-type InGaN layer as the surface protective layer has an effect of functioning as a protective film for the n-type GaN layer.

In addition, an n-type GaN layer is provided on the substrate, and the n-type GaN layer is divided into a selective growth region and a non-selective growth region. It has a laminated structure including a pair of cladding layers composed of a compound semiconductor layer and a layer having an active layer. In a non-selective growth region, an n-type In _x Ga ₁ -xN (0 <x ≦ 1) layer and an n-type It is characterized by having an electrode. By using the re-evaporation step of the n-type InGaN surface protective layer exposed in the selective growth region, there is an effect that a clean regrowth interface can be exposed. There is no increase in series resistance at the interface, and a laminated structure with good crystallinity can be manufactured.

Here, the thickness of the n-type InGaN surface protective layer is preferably 50 nm or more and 100 nm. The reason is that the mixing depth of oxygen and the like is about 20 nm,
m is necessary, and considering the ease of re-evaporation, 100 nm
The following is preferred.

[0010] The In composition ratio of the n-type InGaN surface protective layer is preferably 0 or more and 1 or less, and 0.5 or more and 1 or less for easy re-evaporation. The temperature is preferably from 600 ° C. to 850 ° C. so as not to adversely affect the re-evaporation rate and the n-type GaN underlayer. As for the re-evaporation amount of the n-type InGaN surface protective layer, it is preferable that all of the re-evaporation is performed in order to remove residual impurities mixed into the surface, but it is necessary to re-evaporate at least 20 nm or more.

Further, the present invention provides an n-type GaN on the substrate.
The layer has an n-type impurity concentration of 2 × 10 ¹⁸ cm ⁻³ to 1 × 10 ¹⁹
cm ⁻³ , and the n-type impurity concentration of the semiconductor layer of the multilayer structure in contact with the n-type GaN layer is 8 × 10 ¹⁷ cm.
^-3 to 2 × 10 ¹⁸ cm ^-3 . Further, according to the present light emitting device, it is possible to increase the n-type impurity concentration of the n-type GaN layer configured as the substrate and to select the optimum n-type impurity concentration of the n-type GaN layer of the regrown multilayer structure. Thereby, the light output of the light emitting element can be increased and the series resistance can be reduced. Therefore, in the light emitting device of the present invention, an increase in the light output and a low value of the driving voltage were obtained.

Further, according to the manufacturing method of the present invention, an n-type GaN layer is formed on a substrate, and an n-type GaN layer is formed on the n-type GaN layer.
forming a _{x Ga 1-x N (0} <x ≦ 1) layer, the n
Forming an oxide film on the type In _x Ga _1-x N (0 <x ≦ 1) layer, removing a part of the oxide film, and forming n-type In _x Ga _1-x N ( 0 <x ≦ 1) a step of re-evaporating the layer and a step of laminating a laminated structure in the selective growth region.

Further, a step of removing an oxide film on the n-type In _x Ga ₁ -xN (0 <x ≦ 1) layer remaining in the non-selective growth region; and a step of removing the n-type In _x Ga _{1 -x} An n-type electrode is formed on an N (0 <x ≦ 1) layer.

Further, the ratio of the non-selective growth region to the selective growth region is 0.1 to 0.5. By setting the ratio of the selective growth region to the non-selective growth region as described above, the crystallinity of the regrown laminated structure stacked on the selective growth region is improved.

[0015]

(Embodiment 1) FIG. 1 is a schematic sectional view of a gallium nitride based compound semiconductor light emitting device according to the present invention. In FIG. 1, reference numeral 1 denotes a sapphire substrate, 2 denotes an AlN buffer layer, 3 denotes an n-type GaN layer, and 4 denotes an n-type In.
_0.5 Ga _0.5 N surface protective layer, 5 is an n-type GaN layer, 6 is an n-type Al _0.1 Ga _0.9 N layer, 7 is undoped In _0.3 Ga _0.7 N
A quantum well active layer, 8 is a p-type Al _0.1 Ga _0.9 N cladding layer, 9 is a p-type GaN contact layer, 10 is a p-type electrode, 1
1 is an n-type electrode, 15 is a selective growth region, 50 is a nitride-based compound substrate, and 51 is a laminated structure.

The method of manufacturing the gallium nitride based compound semiconductor light emitting device of the present invention will be described below in detail with reference to FIGS. For example, in the case of manufacturing using metal organic chemical vapor deposition, ammonia NH ₃ is used as a group V material, trimethylgallium, trimethylaluminum, trimethylindium as a group III material, and biscyclopentadienyl magnesium (Cp) as a p-type impurity. ₂ Mg), monosilane is used as the n-type impurity, and hydrogen and nitrogen are used as the carrier gas.

First, a nitride compound substrate 50 is manufactured. Here, metal organic chemical vapor deposition (hereinafter referred to as MOCVD)
Method). An AlN buffer layer 2 is grown on a sapphire substrate 1 at a growth temperature of 550.degree.
Then, an n-type GaN layer 3 having an n-type impurity concentration of 2 × 10 ¹⁸ cm ⁻³ is grown to a thickness of 10 μm, and n-type In _{0.5 is} grown at a growth temperature of 850 ° C.
By forming the Ga _0.5 N surface protective layer 4 to a thickness of 50 nm, a nitride-based compound substrate 50 can be obtained. FIG. 5A is a cross-sectional view of the light-emitting element manufactured up to the above steps. Such a nitride-based compound substrate has an n-type In _0.5 Ga _0.5 N surface.
Since the n-type G is protected by the surface protection layer 4,
A substrate in which impurities such as oxygen do not adsorb to the aN layer 3 can be obtained. Therefore, a substrate that is easy to handle and does not deteriorate in characteristics even when stored can be obtained.

Next, the nitride-based compound substrate 50 is taken out of the growth furnace, and an SiO ₂ film 14 is formed by a P-CVD method.
A selective growth region 15 is formed on the SiO ₂ film 14 by photolithography and etching. FIG. 5B is a cross-sectional view of the light-emitting element manufactured up to the above steps. here,
Nitride compound substrate 50 on which selective growth region 15 is formed
FIG. 5 (c) shows a schematic top view of FIG. The shape of the selective growth region 15 is a shape in which one corner of a square 350 μm × 350 μm is cut out, but it goes without saying that another shape may be used.

In addition, for the manufacture of the nitride-based compound substrate 50, a hydride vapor phase epitaxy method (hereinafter, referred to as a high growth rate) having an excellent growth rate is used.
HVPE method). Hereinafter, in the case of the nitride-based compound substrate 50 manufactured using the HVPE method, ammonia NH _{3 is used} as a group V material, metal gallium and metal indium as a group III material, and H ₂ S is used as an n-type impurity.
Using H ₂ Se, it is reacted with a mixed gas of HCl and H ₂ . An n-type GaN layer 3 having an n-type impurity concentration of 2 × 10 ¹⁸ cm ⁻³ is laminated on the substrate at a substrate temperature of 1000 ° C., and then an n-type In _0.5 Ga _0.5 N surface protection layer is formed at a substrate temperature of 800 ° C. 4
Are stacked, a nitride-based compound substrate 50 is obtained.

Next, in order to form the laminated structure 51 on the nitride-based compound substrate 50 by regrowth, the MOCVD is performed again.
A nitride-based compound substrate 50 is introduced into the apparatus. First, a part of the n-type In _0.5 Ga _0.5 N surface protection layer 4 (selective growth region 1) is set in a nitrogen atmosphere at a substrate temperature of about 800 ° C. for 10 minutes.
5) is removed until the surface of the n-type GaN layer 3 is exposed.
FIG. 6D is a cross-sectional view of the light-emitting element manufactured up to the above steps.
Shown in Here, the n-type In _0.5 Ga _0.5 N surface protective layer 4
Functions as a layer to be re-evaporated (hereinafter, referred to as a re-evaporation layer) when forming a light emitting element.

Next, an n-type GaN layer 5 having an n-type impurity concentration of 2 × 10 ¹⁸ cm ^-3 is grown to 4 μm at a growth temperature of 1050 ° C.
The n-type Al _0.1 Ga _0.9 N layer 6 is 0.3 μm and the growth temperature is 8
The temperature is lowered to 00 ° C., and an undoped In _0.3 Ga _0.7 N quantum well active layer 7 is grown to 3 nm. Next, the growth temperature is set to 1050 ° C.
And the p-type Al _0.1 Ga _0.9 N cladding layer 8 is 0.3 μm thick.
The m and p-type GaN contact layers 9 are sequentially crystal-grown by 0.5 μm. Next, to inject current from outside,
forming a p-type electrode 10 on the p-type GaN contact layer 9;
In order to form the n-type electrode 11, the SiO ₂ film 14 is removed with a hydrofluoric acid-based etchant to expose the surface of the n-type In _0.5 Ga _0.5 N surface protection layer 4.
To form FIG. 6E is a cross-sectional view of the light-emitting element manufactured up to the above steps. At this time, the non-selective growth region is formed on the SiO ₂ film 14, and the stacked structure 51 is not grown. Finally, the device was divided into chips.

In this embodiment, the n-type In _0.5 Ga
_{The 0.5} N surface protective layer 4 is configured as a light emitting element that functions as a re-evaporation layer, so that re-growth is not performed immediately in the process of the re-growth layer, and crystal defects at the re-growth interface are reduced because the re-evaporation step is used. By doing so, the electrical series resistance could be reduced.

Furthermore, since the n-type In _0.5 Ga _0.5 N surface protective layer 4 is a soft crystal and has few crystal defects,
N _0.5 In _0.5 Ga _0.5 N surface protection layer 4
When the upper SiO ₂ film 14 is etched, the n-type electrode 1 has a smaller number of etch pits and surface roughness than the n-type GaN layer 3 and has less n-type impurity concentration near the surface.
(1) It is possible to form an electrode having a reduced contact resistance and excellent reproducibility.

For this reason, the driving voltage is as low as about 3.3 V,
Further, since a gallium nitride-based compound semiconductor light emitting device with excellent reproducibility and improved reliability can be manufactured, the manufacturing has been greatly simplified and the price of the chip has been significantly reduced.

(Embodiment 2) FIG. 2 is a schematic sectional view of a gallium nitride based compound semiconductor laser of the present invention. The same members as those in the first embodiment are denoted by the same reference numerals. In this embodiment, the same materials and gases as those used in Example 1 were used in the MOCVD method and the HVPE method.

In the present embodiment, the nitride-based compound substrate 50
In the n-type GaN layer 3, an SiH ₄ flow rate in making 1
The resistivity was 8 sccm, the resistivity was 0.0072 Ω · cm, and the n-type impurity concentration was about 4 × 10 ¹⁸ cm ⁻³ . Other than that, it is the same as the nitride-based compound substrate 50 of the first embodiment. FIG.
FIG. 3 shows the relationship between the flow rate of SiH ₄ added to the n-type GaN layer and the resistivity. It is shown that the resistivity decreases with increasing SiH ₄ flow rate. In this embodiment, n-type GaN
Although the n-type impurity concentration of the layer 3 is set to 4 × 10 ¹⁸ cm ⁻³ , a preferable range of the n-type impurity concentration is 2 × 10 ¹⁸ cm ⁻³ to 1
× 10 ¹⁹ cm ^-3 . n-type impurity concentration is 2 × 10 ¹⁸ c
When the resistivity is less than m ^-3, the series resistance of the semiconductor laser increases because of the large resistivity. When the resistivity is more than 1 × 10 ¹⁹ cm ^-3 , the n-type G
Since irregularities occur on the surface of the aN layer 3 and crystallinity deteriorates, the n-type impurity concentration is preferably 2 × 10 ¹⁸ cm ⁻³ to 1 × 10 ¹⁹ cm ⁻³ .

Next, in order to form the laminated structure 51, M
The nitride compound substrate 50 is introduced into the OCVD apparatus.
As in the first embodiment, the n-type GaN layer 5 and the n-type Al _0.1
A Ga _0.9 N layer 6 and an undoped In _0.3 Ga _0.7 N quantum well active layer 7 are formed. Here, the SiH ₄ of the n-type GaN layer 5
Flow rate is 6 sccm, and n-type impurity concentration is about 1 × 10 ¹⁸ c
m- ³ . FIG. 10 shows the relationship between the SiH ₄ flow rate and the light output when forming the n-type GaN layer 5. By optimizing the SiH ₄ concentration as shown in FIG. 10, the light output can be maximized. n-type GaN layer 3
Of the n-type GaN layer 5 for the range of n-type impurity concentration of
Mold impurity concentration of 8 × 10 ¹⁷ cm ⁻³ to 2 × 10 ¹⁸ cm ⁻³
, The optical output can be almost maximized.

Further, an n-type Al _0.1 Ga _0.9 N current blocking layer 80 is stacked, and a p-type regrown Al _0.1 Ga _0.9 N cladding layer 81 and a p-type regrown GaN contact layer 82 are sequentially stacked. Next, in order to inject a current from the outside, the p-type electrode 1
0, an n-type electrode 11 is formed. Finally, the device was divided into chips.

In the conventional selective growth method, when an n-type semiconductor layer is stacked on the n-type GaN layer 5 having a high impurity concentration as in this embodiment, n-type Ga having a high n-type impurity concentration is used.
There has been a problem that irregularities occur on the surface of the N layer.

However, according to the present light emitting device structure,
By increasing the n-type impurity concentration of the n-type GaN layer configured as a substrate and optimizing the n-type impurity concentration of the n-type GaN layer of the regrown multilayer structure, the light output of the light-emitting element is increased and the series resistance is increased. Can be reduced. Therefore, in the light emitting device of the present invention, an increase in the light output and a low value of the driving voltage were obtained.

(Embodiment 3) FIG. 3 is a schematic sectional view of a gallium nitride based compound semiconductor light emitting device of the present invention.
The same members as those in the first embodiment are denoted by the same reference numerals. Hereinafter, a method for manufacturing the gallium nitride-based compound semiconductor light emitting device of the present invention will be described in detail with reference to FIGS.

As the nitride-based compound substrate 50 used here, a substrate having the same configuration as in the first embodiment was used. FIG. 7A is a cross-sectional view of a light-emitting element manufactured up to the above steps.

Next, the nitride-based compound substrate 50 is taken out of the growth furnace, and a P-type layer is formed on the n-type In _0.5 Ga _0.5 N surface protective layer 4.
Forming a 200 μm square SiO ₂ film 14 as a region to be an electrode by the CVD method; FIG. 7B is a schematic top view of the light-emitting element manufactured up to the above steps. Where Si
Although the shape of the O ₂ film 14 is a 200 μm square shape, it goes without saying that another shape may be used.

Next, the nitride compound substrate 50 is introduced into the MOCVD apparatus in order to form a laminated structure on the nitride compound substrate 50 by regrowth. First, the substrate temperature 8
N-type In while irradiating with nitrogen at about 00 ° C. for 10 minutes
_{The 0.5} Ga _0.5 N surface protective layer 4 is removed until the surface of the n-type GaN layer 3 is exposed. By leaving the SiO ₂ film 14, the n-type In _0.5 Ga _0.5 N surface protective layer 4 is not removed in the non-selective growth region. FIG. 7C is a cross-sectional view of the light-emitting element manufactured up to the above steps. Here, n-type In _0.5 G
The a _0.5 N surface protective layer 4 functions as a reevaporation layer.

Next, the n-type GaN layer 5 and the n-type Al _0.1 Ga _0.9
An N layer 6, an undoped In _0.3 Ga _0.7 N quantum well active layer 7, a p-type Al _0.1 Ga _0.9 N clad layer 8, and a p-type GaN contact layer 9 are sequentially formed as in the first embodiment.
Note that the stacked structure 51 is not formed on the SiO ₂ film 14 because it is a non-selective growth region. FIG. 8D is a cross-sectional view of the light-emitting element manufactured up to the above steps.

Next, in order to inject a current from the outside, p
Electrode 10 is formed on the p-type GaN contact layer 9 and n
In order to form the type electrode 11, the SiO ₂ film 14 is removed with a hydrofluoric acid-based etchant to expose the surface of the n-type In _0.5 Ga _0.5 N surface protection layer 4, and the n-type electrode 11 is formed on this surface. I do. FIG. 8E is a schematic top view of the light-emitting element manufactured up to the above steps.

Finally, the scribe line 2 on the wafer
By scribing or dicing along 0,
The light emitting element was divided into chips.

In this embodiment, since the area of the non-growth region is small, the influence of the SiO ₂ film 14 on the regrowth is small, and a good laminated structure 51 can be formed. It is preferable that the area ratio between the non-selective growth region and the selective growth region is 0.1 or more and 0.5 or less. If the area ratio between the non-selective growth region and the selective growth region is 0.1 or less, it becomes difficult to form an electrode. If the area ratio is 0.5 or more, the crystallinity of the semiconductor layer in the selective growth region deteriorates.

Further, since the n-type electrode formation region can be exposed without using dry etching, the electrode can be formed without damaging the crystal plane, so that the contact resistance of the n-type electrode is reduced and the electrode is excellent in reproducibility. Can be formed.
Therefore, a gallium nitride-based compound semiconductor light-emitting device having a low driving voltage of about 3.3 V, excellent reproducibility, and improved reliability can be manufactured, and a gallium nitride-based compound semiconductor light-emitting device can be easily manufactured without using dry etching. Therefore, the fabrication was greatly simplified and the price of the chip was significantly reduced. Also, as in the first embodiment, the n-type electrode 1
The contact resistance of No. 1 was also reduced.

(Embodiment 4) FIG. 4 is a schematic sectional view of a gallium nitride-based compound semiconductor laser according to the present invention. In the present embodiment, the sapphire substrate 1 of the nitride-based compound substrate 50 uses the conductive substrate 41, does not form the buffer layer 2, and forms the nitride-based compound substrate 50 with the n-type InN surface protection layer 44. did. Here, the conductive substrate 41 may be, for example, an n-type SiC substrate or an n-type GaN substrate.

Next, in order to form the laminated structure 51, M
The nitride-based compound substrate 50 is introduced into the OCVD apparatus, the n-type InN surface protective layer 44 is re-evaporated at a processing temperature of 600 ° C., and the laminated structure 51 described in the first embodiment is sequentially laminated. Next, in order to inject a current from the outside, the p-type electrode 1
The 0, n-type electrode 11 is formed on the back side of the nitride-based compound substrate 50. Finally, the device was divided into chips. The dotted line 44 shown in FIG. 4 represents the film reduced by the re-evaporation.

In this embodiment, the nitride-based compound substrate 50 for forming the light emitting element is composed of at least a conductive substrate and an n-type InN surface protection layer 44. Therefore, since the conductive substrate 41 is used, electrode formation is easy.
Further, since the surface protective layer is made of InN, the re-evaporation temperature can be lowered, and the re-evaporation is easy. In the process of the regrowth layer, the series resistance at the regrowth interface could be reduced because the n-type InN surface protection layer 44 functions as a reevaporation layer. As a result, a gallium nitride-based compound semiconductor laser having a low driving voltage of about 3.5 V, excellent reproducibility, low cost of chips, and improved reliability was produced.

[0043]

According to the present invention, InGaN is applied to the outermost surface of the substrate.
By using a layer structure in which a surface protective layer made of is formed as a substrate, it is possible to provide a substrate which is easy to handle and whose characteristics are not deteriorated even when stored. Further, when such a substrate is used as a light emitting element, the surface protective layer functions as a reevaporation layer, so that the n-type GaN layer having a clean surface can be exposed, and the interface of regrowth may cause generation of etch pits. And rough surfaces,
Since the adhesion of impurities in the air atmosphere can be reduced, the series resistance at the regrowth interface can be reduced.

Further, in the case of a light emitting device having an n-type electrode and a p-type electrode on the same surface, by providing the electrode on the InGaN layer, an electrode with reduced contact resistance of the n-type electrode and excellent reproducibility can be formed. be able to.

Therefore, it is possible to provide a gallium nitride-based compound semiconductor light emitting device having a low driving voltage, excellent reproducibility, low cost of chips, and improved reliability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a gallium nitride-based compound semiconductor light emitting device of the present invention.

FIG. 2 is a sectional view of a gallium nitride-based compound semiconductor laser according to the present invention.

FIG. 3 is a cross-sectional view of a gallium nitride-based compound semiconductor light emitting device of the present invention.

FIG. 4 is a sectional view of a gallium nitride based compound semiconductor laser of the present invention.

FIG. 5 is a schematic diagram of a manufacturing process of the gallium nitride-based compound semiconductor light emitting device of the first embodiment.

FIG. 6 is a schematic view of a manufacturing process of the gallium nitride-based compound semiconductor light emitting device of the first embodiment.

FIG. 7 is a schematic diagram of a manufacturing process of the gallium nitride-based compound semiconductor light emitting device of Embodiment 3.

FIG. 8 is a schematic diagram of a manufacturing process of the gallium nitride-based compound semiconductor light emitting device of Embodiment 3.

FIG. 9 is a diagram showing the relationship between the flow rate of SiH _{4 in the} n-type GaN layer and the resistivity.

FIG. 10 is a diagram showing a relationship between a SiH ₄ flow rate of an n-type GaN layer and a light output.

FIG. 11 is a cross-sectional view of a conventional gallium nitride-based compound semiconductor light emitting device.

[Explanation of symbols]

1 sapphire substrate 2 AlN buffer layer 3 n-type GaN layer 4 n-type In _0.5 Ga _0.5 N the surface protective layer 5 n-type GaN layer 6 n-type Al _0.1 Ga _0.9 N cladding layer 7 undoped In _0.3 Ga _0.7 N quantum well active layer 8 p-type Al _0.1 Ga _0.9 N cladding layer 9 p-type GaN contact layer 10 p-type electrode 11 n-type electrode 14 SiO ₂ film 15 selective growth region 41 conductive substrate 50 nitride-based compound substrate 51 laminated structure 80 n-type Al _0.1 Ga _0.9 N current blocking layer 81 p-type regrown Al _0.1 Ga _0.9 N cladding layer 82 p-type regrown GaN contact layer 100 sapphire substrate 110 n-type low-temperature GaN buffer layer 120 n-type GaN layer 130 n-type AlGaN cladding layer 140 InGaN activity Layer 150 p-type AlGaN cladding layer 160 p-type GaN cap layer 170 n-type electrode 1 0 p-type electrode 200 for oxide film growth region 210 selective growth

Claims (6)

[Claims] 1. An n-type GaN layer and an n-type In _x Ga on a substrate
_{A 1-x} N (0 <x ≦ 1) layer, wherein the n-type In _x Ga _1-x
A gallium nitride-based compound semiconductor substrate, wherein the N (0 <x ≦ 1) layer is a surface protective layer. 2. An n-type GaN layer is provided on a substrate, and the n-type GaN layer is divided into a selective growth region and a non-selective growth region. It has a laminated structure including a pair of cladding layers made of a compound semiconductor layer and a layer having an active layer. In a non-selective growth region, n-type In _x Ga ₁ -xN (0 <x ≦
1) A gallium nitride-based compound semiconductor light-emitting device having a layer and an n-type electrode. 3. The laminated structure in contact with the n-type GaN layer, wherein an n-type impurity concentration of the n-type GaN layer on the substrate is in a range of 2 × 10 ¹⁸ cm ⁻³ to 1 × 10 ¹⁹ cm ^−3. The n-type impurity concentration of the body semiconductor layer is 8 × 10 ¹⁷ cm ⁻³ to 2 × 10 ¹⁸ cm
3. The gallium nitride-based compound semiconductor light emitting device according to claim 2, wherein the range is ^-3 . 4. An n-type GaN layer is formed on a substrate.
Type GaN n-type on the layer _{In x Ga 1-x N (} 0 <x ≦ 1) forming a layer, the n-type _{In x Ga 1-x N (} 0 <x ≦ 1) oxide film on the layer Forming an oxide film on the selective growth region and re-evaporating an n-type In _x Ga ₁ -xN (0 <x ≦ 1) layer in the selective growth region; And a step of laminating a laminated structure on the gallium nitride-based compound semiconductor light emitting device. 5. The n-type I in which a non-selective growth region remains.
removing the _{n x Ga 1-x N (} 0 <x ≦ 1) oxide film on the layer to form an n-type electrode on the n-type _{In x Ga 1-x N (} 0 <x ≦ 1) layer The method for manufacturing a gallium nitride-based compound semiconductor light emitting device according to claim 4, wherein: 6. The method according to claim 4, wherein a ratio of the non-selective growth region to the selective growth region is 0.1 to 0.5.