JP2002305322A - Group iii nitride semiconductor light emitting device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide cladding and emitting layers that are suitable for composing a light emitting section in hetero junction structure having high light emitting output in a group III nitride semiconductor light emitting device using an Si signal crystal as a substrate. SOLUTION: A low-temperature buffer layer is made of Bα GaγAs1- YPY. The clad layer is made of Bα Alβ GaγAs1-δ Pδ . The light emitting layer is made of GaNZP1- Z that is lattice-matched with the clad layer. On an Si substrate whose orientation is 111}, the light emitting section comprising the cladlayer and the light emitting layer is formed via the low-temperature buffer layer, thus composing the group III nitride semiconductor light emitting device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a single crystal substrate,
The present invention relates to a technology for forming a high-output group-III nitride semiconductor light-emitting device by providing a light-emitting portion having a heterojunction structure capable of emitting light from near-ultraviolet light to short-wavelength visible light.

[0002]

2. Description of the Related Art Electrically insulating sapphire (α-Al ₂ O ₃₎
Instead of single crystal), silicon (Si) single crystal (silicon)
III-nitride semiconductor light emitting diode (L
(ED) is disclosed (Electr).
on. Lett. , 33 (23) (1997), 198.
6-1987). When a substrate is made of a conductive Si single crystal, an electrode can be laid on the back surface of the substrate, and there is an advantage that an LED can be easily configured. Further, if a substrate is made of a Si single crystal, there is also an advantage that it can be easily divided into individual elements (chips) using the cleavage of the diamond crystal structure type in the [110] direction (Appl. Phys. Lett., 72 ( 4)
(1998), 415-417).

In a conventional group III nitride semiconductor light-emitting device using a Si single crystal as a substrate, it is customary to provide a low-temperature buffer layer formed at a relatively low temperature on the surface of the substrate (see Appl. Phys. Lett.). The low temperature buffer layer
Lattice mismatch with silicon single crystal substrate
Mismatch) is provided to obtain a constituent layer of a light emitting portion having a pn junction type heterojunction structure having excellent crystallinity. Conventionally, an example in which the low-temperature buffer layer is made of aluminum nitride (AlN) is known (Japanese Patent Laid-Open No. Hei 10-242586). In addition, boron phosphide (B
A technique for forming a low-temperature buffer layer from P) is known (JP-A-2-288388). There is also known an example in which a buffer layer is constituted by a multilayer structure in which a high-temperature buffer layer also made of boron phosphide (BP) is laminated on a low-temperature buffer layer made of boron phosphide (US Pat. No. 6,029). , 021
issue).

On a cubic crystal substrate such as a Si single crystal, 85
Utilizing a light emitting portion provided through a boron phosphide (BP) buffer layer grown at a relatively high temperature of 0 ° C. to 1150 ° C. in a vapor phase,
A technique for forming a group II nitride semiconductor LED has also been disclosed (Japanese Patent Application Laid-Open No. 2-288371). Sphalerite (z
The light emitting portion provided on the buffer layer composed of an inclining (BP) crystal type BP crystal layer is composed of a cubic group III nitride semiconductor layer (see Japanese Patent Application Laid-Open No. 2-2 / 1990).
No. 88371). Conventionally, a cladding (barrier) layer serving as a light emitting portion provided on a BP buffer layer is formed of a mixed crystal of BP and aluminum gallium nitride (Al _x Ga ₁ -x N: 0 ≦ X ≦
An example comprising a superlattice structure consisting of 1) is known (the above-mentioned JP-A-10-242567).

Further, a conventional Si single crystal substrate is used.
In a group I nitride semiconductor light emitting device, there is an example in which a heterojunction light emitting portion provided on a buffer layer is formed of a group III nitride semiconductor crystal layer containing nitrogen (N) as a sole group V constituent element.
For example, an aluminum nitride-gallium-indium mixed crystal layer (Al _X Ga _Y In _1-XY N: 0 ≦ X ≦ 1, 0 ≦ Y ≦
1, 0 ≦ X + Y ≦ 1
-321911). In addition, n-type and p-type Al _0.2
There is an example in which a light emitting portion having a pn junction type double hetero (DH) structure is constituted by a cladding layer made of Ga _0.8 N and a light emitting layer made of GaN (see JP-A-10-242586 described above).
No.). Further, there is also known an example in which the light emitting unit is formed from a group III nitride semiconductor containing a group V element other than nitrogen (N) as a constituent element. For example, Ga _0.3 Al _0.3 N _0.6 B
_{From 0.4} P _0.4 and Ga _0.25 Al _0.25 N _0.5 B _0.5 P _0.5
An n-junction type light emitting portion is configured (see the above-mentioned Japanese Patent Application Laid-Open No.
No. 88371).

However, the light emitting section in the above conventional example is
It does not consist of a group III nitride semiconductor containing nitrogen and a group V constituent element other than nitrogen, which have a lattice matching relationship with each other. As described above, the light emitting portion of the conventional group III nitride semiconductor LED using the Si single crystal as the substrate has a lattice mismatched structure composed of the group III nitride semiconductor layers having different lattice constants (described above). Appl.Phy
s. Lett, 72 (4) (1998) and Elec
tron. Lett. , 33 (23) (1997)).
Rather, the composition ratio of phosphorus (P) is made equal to the sum of the composition ratios of gallium (Ga) and aluminum (Al) so that the inter-bond distances (bond lengths) of the constituent elements (atoms) are equal to each other. It has been taught that it is important to form the light emitting section from a group III nitride semiconductor (see Japanese Patent Application Laid-Open No. 2-28-28).
No. 8371).

[0007]

SUMMARY OF THE INVENTION In the prior art,
A cubic Si single crystal (lattice constant: 5.431 °) or a gallium phosphide single crystal (Ga) exemplified as a substrate material
P: a lattice constant of 5.450 °) and BP (a lattice constant of 4.538 °), which is a constituent material of the conventional buffer layer, have different lattice constants. For example, a Si single crystal and a BP single crystal have a lattice mismatch of about 16% ("Journal of the Japan Society for Crystal Growth", Vol. 24, No. 2 (199).
7), p. 150). For this reason, for example, the adhesion between the surface of the Si single crystal and the BP buffer layer is inferior, and there is a defect that the BP buffer layer grown at a high temperature in a vapor phase is separated from the surface of the Si single crystal substrate. The weakness of the adhesion makes it possible to reduce the flow of the element operating current between the back electrode provided on the back side of the substrate and the front electrode provided above the light emitting portion by utilizing the good conductivity of the Si single crystal substrate. Inhibiting resistance. Therefore, for example, L
In the case of the ED, a problem such as a sudden increase in the forward voltage (Vf) has been induced.

Further, when the light-emitting portion is made of a group III nitride semiconductor having a lattice mismatch with each other as described above,
A light emitting unit that emits high-output light cannot be configured stably. This is because, for example, a light emitting layer laminated with a lower clad layer having a lattice mismatch relationship as an underlayer has a crystallinity including a large number of crystal defects such as misfit dislocations caused by lattice mismatch (mis-match). It is because it becomes inferior. As described above, the conventional lattice mismatch type light emitting layer has a problem that the light emission intensity of the light emitting element cannot be sufficiently increased. In order to obtain a group III nitride semiconductor light emitting device having a high light emission output, it was necessary to form the light emitting layer from a crystal layer having a low density of crystal defects caused by lattice mismatch.
In addition, it is important that the light emitting portion is also formed of a group III nitride semiconductor layer having excellent crystallinity. In addition, these light-emitting portions need to be provided on a buffer layer having excellent adhesion to a single crystal substrate.

The present invention provides a high-quality Group III nitride semiconductor having a low crystal defect density caused by lattice mismatch by laminating a light emitting layer with a cladding layer having a lattice matching relationship with the underlayer. Providing a means for constituting a light emitting portion composed of layers, and also by providing a technique for providing a buffer layer having excellent adhesion with a substrate crystal suitable for laminating such a lattice matching type light emitting portion, The present invention clarifies the structure of a group III nitride semiconductor light emitting device having excellent rectification characteristics and high light emission output, and a method of manufacturing the same.

[0010]

That is, the present invention provides (1) a substrate comprising a single crystal, and boron (B) and arsenic (As) or phosphorus (P) provided on the surface of the substrate.
A III-nitride semiconductor light-emitting device comprising a buffer layer including a low-temperature buffer layer made of a group V compound semiconductor, and a light-emitting portion having a heterojunction structure of a clad layer and a light-emitting layer provided on the buffer layer; The cladding layer is composed of a group III-V compound semiconductor single crystal layer containing boron (B) and phosphorus (P), and nitrogen (N) and a group V element other than nitrogen, which lattice-match the light emitting layer to the cladding layer. A group III nitride semiconductor light-emitting device comprising a group III nitride semiconductor layer.

In the present invention, in addition to the configuration of (1),
(2) a cladding layer was grown at a temperature higher than the low-temperature buffer layer, the formula _{B α Al β Ga γ As 1-} δ P δ (0 <α ≦
1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ
.Ltoreq.1).

In the present invention, particularly in the configuration of (2),
(3) The cladding layer is formed by a general formula B _α Ga _γ P (0 <α ≦
1, 0 ≦ γ <1, α + γ = 1)
It is preferable to use a group II-V compound semiconductor single crystal.

Further, in the present invention, in addition to any one of the constitutions (1) to (3), (4) the light emitting layer is made of gallium nitride phosphide (GaN _Z P _{1 -Z} : 0 <Z <1). It is characterized by comprising.

According to the present invention, in addition to any one of the constitutions (1) to (4), (5) the substrate has a plane orientation of # 11.
It is characterized in that it is an n-type or p-type silicon (Si) single crystal with 1｝.

According to the present invention, in addition to any one of the constitutions (1) to (5), (6) the low-temperature buffer layer is formed of B _α Ga _γ A
s _1-Y P _Y (0 <α ≦ 1, 0 ≦ γ <1, α + γ = 1, 0 ≦
Y ≦ 1).

The present invention also provides (7) a low-temperature buffer layer made of a III-V compound semiconductor containing boron (B) and arsenic (As) or phosphorus (P) on a surface of a substrate made of a single crystal. Forming a buffer layer including a heterojunction structure of a cladding layer and a light emitting layer on the buffer layer, the cladding layer is formed of boron (B) and phosphorous. A light emitting layer composed of a group III-V compound semiconductor single crystal layer containing (P) and a group III nitride semiconductor layer containing nitrogen (N) and a group V element other than nitrogen which lattice-match with the cladding layer; A method of manufacturing a group III nitride semiconductor light-emitting device.

In the present invention, in addition to the configuration of (7),
(8) a clad layer was grown at a temperature higher than the low-temperature buffer layer, the formula _{B α Al β Ga γ As 1-} δ P δ (0 <α ≦
1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ
.Ltoreq.1), and is made of a conductive group III-V compound semiconductor single crystal.

In the present invention, particularly in the configuration of (8),
(9) The cladding layer is formed by a general formula B _α Ga _γ P (0 <α ≦
1, 0 ≦ γ <1, α + γ = 1)
It is preferable to use a group II-V compound semiconductor single crystal.

In the present invention, in addition to any one of the constitutions (7) to (9), (10) the light emitting layer is made of gallium nitride phosphide (GaN _Z P _{1 -Z} : 0 <Z <1). It is characterized by comprising.

According to the present invention, in addition to any one of the constitutions (7) to (10), (11) the substrate has a plane orientation of {1}.
It is characterized by being an n-type or p-type silicon (Si) single crystal having an angle of 11 °.

Further, according to the present invention, in addition to any one of the constitutions (7) to (11), (12) the low-temperature buffer layer is formed of B _α Ga
_γ As _1−Y P _Y (0 <α ≦ 1, 0 ≦ γ <1, α + γ = 1,
0 ≦ Y ≦ 1).

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The group III nitride semiconductor light emitting device according to the present invention can be constituted by using a high resistance or insulating single crystal as a substrate, but the light emitting device of the first embodiment has n
The substrate is formed by suitably using a single crystal of p-type or low conductivity having low resistance as a substrate. If a single crystal having good conductivity is used as the substrate, electrodes can be laid on the substrate, and the electrodes can be easily installed. For example, a single crystal such as gallium phosphide (GaP), silicon (Si), silicon carbide (SiC), or gallium arsenide (GaAs) exhibiting n-type or p-type conductivity can be used as the substrate. A highly conductive single crystal having a specific resistance (resistivity) of several milliohm-cm (mΩ · cm) or less can be particularly preferably used. Also, 10
Even when stacking a group III nitride semiconductor layer at a high temperature exceeding 00 ° C., the substrate needs to be a single crystal having heat resistance without being denatured. S from good conductivity and heat resistance
An i-single crystal can be recommended as a suitable substrate material. Further, in a laser diode (LD) using a diamond crystal structure type Si single crystal as a substrate, the convenience of being able to easily form a mirror optical resonance surface by using a cleavage crystal plane in the [110] crystal direction of the substrate is provided. is there.

LED or LD according to the first embodiment
Buffer layer such as boron phosphide (BP: lattice constant 4.
538 °) and its mixed crystal, or boron arsenide (BAs: lattice constant 4.777 °) and its mixed crystal. From boron phosphide (BP) mixed crystal and boron arsenide (BAs) mixed crystal, Si
There is an advantage that a buffer layer that lattice-matches with a single crystal (lattice constant 5.431 °) can be formed. For example, constituting the buffer layer lattice-matched to the Si single crystal boron phosphide indium mixed crystal (B _0.33 In _{0. 67} P) or arsenide boron indium mixed crystal or the like (B _0.40 In _0.60 As). On the buffer layer made of a group III-V compound semiconductor material containing boron (B) and phosphorus (P) or arsenic (As) having a composition lattice-matched with the Si single crystal, a crystal caused by lattice mismatch is formed. The advantage is that a good quality deposited layer with few defects is provided.

The buffer layer can have a multilayer structure of a low-temperature buffer layer grown at a lower temperature than the next high-temperature buffer layer and a high-temperature buffer layer grown at a higher temperature than the low-temperature buffer layer. Disposing the low-temperature buffer layer between the substrate and the high-temperature buffer layer has an effect of preventing the growth layer from being separated from the substrate. In particular, when a lattice mismatch exists between the substrate crystal and the buffer layer, the low-temperature buffer layer has an effect of relaxing the mismatch to provide a high-temperature buffer layer having excellent crystallinity. For example, triethyl boron ((C ₂ H ₅ ) ₃ B) / phosphine (PH ₃ ) /
In order to obtain a low-temperature buffer layer composed mainly of amorphous boron phosphide (BP) using a hydrogen (H ₂ ) reaction-based MOCVD method, the growth temperature is, for example, about 250 ° C. to about 750.
C is suitable (US Pat. No. 6,069,021).
The low-temperature buffer layer is grown at a lower temperature than the cladding layer to be grown next. Also, as the thickness of the low-temperature buffer layer,
Generally, several nanometers (nm) to several tens nm are suitable. The high temperature buffer layer may not be required.

The clad layer according to the first embodiment, in particular, the lower clad layer provided on the buffer layer can be made of, for example, boron phosphide (BP). Or,
It can be composed of boron arsenide (BAs). Electronegativity (select) of boron (B) and phosphorus (P) constituting boron phosphide
Ronegatility is 2.0 and 2.1, respectively (Takeo Kawaguchi, "Semiconductor Chemistry" (February 10, 1967, published by Maruzen Co., Ltd., 3rd edition, p. 104)). ) And arsenic (As) have an electronegativity of 2.0 (see “Semiconductor Chemistry” above), ie, boron phosphide (B
P) or boron arsenide (BAs) or a mixed crystal thereof (B
The difference in electronegativity between the elements constituting As _1-X P _X : 0 ≦ X ≦ 1) is slight. Therefore, in these crystals, the bonds between the constituent atoms are all based on covalent bonds, and the ratio of ionic bonds is small. For example, in gallium nitride (GaN), the ionic bond is calculated to be as large as about 34.6%, whereas that of boron phosphide (BP) is only 1.64% (Kazuo Fueki et al.) Author, "Chemistry of Electronic Materials" (July 20, 1981,
Maruzen Co., Ltd., pp. 27-28). In addition, boron arsenide (B
In As), the ionicity is 0%, that is, it is suggested that all the bonds are covalent bonds ("Chemistry of Electronic Materials", pp. 27-28, supra). Therefore, in a group III-V compound semiconductor containing boron (B) and phosphorus (P) or arsenic (As), the electrical activation rate of impurities doped into the crystal becomes large, and a low-resistance crystal layer is obtained. There is an advantage that is easy to be. Therefore, boron (B) and phosphorus (P) or arsenic (A
s) as a constituent element, the cladding layer may be made of a group III-V compound semiconductor, for example, LE
D has the advantage of being able to form a cladding layer that is effective in reducing the forward voltage (Vf).

The cladding layer can be made of the same material as the buffer layer. For example, the cladding layer can be composed of a boron phosphide (BP) crystal layer deposited on a boron phosphide (BP) buffer layer. Further, the buffer layer and the cladding layer may be made of different semiconductor materials. Regardless of the material configuration, for example, in order to increase the light emission area by increasing the light emission area in an LED, the cladding layer is required to be a crystal layer having good conductivity. Therefore, in the second embodiment of the present invention, the cladding layer is made of a crystal layer grown at a higher temperature than the low-temperature buffer layer. In particular, it is composed of a crystal layer grown at a high temperature to become a single crystal. From a single-crystal layer, for example, short-circuit or local element operation current can be prevented from flowing through a grain boundary in a polycrystalline layer.
The effect is obtained in that the operating current is diffused over a wide range of the light emitting layer and the light emitting region is expanded.

In particular, B _α Al _β Ga _γ As _{1- δ} P _δ (0 <α ≦ 1, 0 ≦ β <
1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ ≦ 1) The cladding layer can be suitably formed from a single crystal layer. A group III-V compound semiconductor containing boron (B) and phosphorus (P) or arsenic (As) as constituent elements has a high electrical activation rate of doping impurities for the above-described reason, and thus has good conductivity. This is advantageous for obtaining a clad layer. In addition, aluminum arsenide (AlAs) or aluminum phosphide (AlP)
And BP or BAs are mixed, BP (lattice constant 4.538 °) or BAs (lattice constant 4.777)
A mixed crystal layer having a lattice constant other than the binary crystal of の) can be formed. For example, a zinc blende crystal type B _α Al _β As _{1- δ}
P _δ (0 <α ≦ 1, 0 ≦ β <1, α + β = 1, 0 <δ ≦
From 1), 4.538 ° to 5.661 ° (AlAs
Is the lattice constant of A cladding layer composed of a single crystal layer having a lattice constant in the range of (1) can be formed. Gallium arsenide (G
GaAs) or B gallium phosphide and (GaP) and BP or BAs were mixed crystal _{α Ga γ As 1- δ P δ} (0 <
α ≦ 1, 0 ≦ γ <1, α + γ = 1, 0 <δ ≦ 1) From the single crystal layer, a single crystal having a lattice constant in the range of 4.538 ° to 5.653 ° (a lattice constant of GaAs). A clad layer composed of layers can be formed. That is, B _α Al _β Ga _γ A
s _{1− δ} P _δ (0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α
+ Β + γ = 1, 0 <δ ≦ 1) From the single crystal layer, 4.53
There is an advantage that a cladding layer having an arbitrary lattice constant in a wide range of 8 ° to 5.661 ° and having excellent conductivity can be formed. That is, BP or BAs or BAs
_1-X P _X a buffer layer made of a mixed crystal can be accomplished lattice matching, therefore, an advantage of constituting less quality clad layer crystal defects due to lattice misfit.

A single heterojunction structure (S
H) The electric conduction type of the cladding layer constituting the light emitting portion is a buffer layer
To match that of. Double heterojunction
In the (DH) structured light emitting section, the lower cladding layer is the same as the buffer layer.
And the conduction type of the upper cladding layer is the lower conduction type.
Opposite to the layer. For example, for the n-type lower cladding layer,
Therefore, the upper cladding layer is grown at a higher temperature than the low-temperature buffer layer.
It comprises a p-type single crystal layer. The light emitting layer is, for example, a buffer.
A crystal layer of the same conductivity type as the lower cladding layer provided on the layer side or
Or it can be composed of a crystal layer of the opposite conductivity type. Preferably,
B_αAl_βGa_γAs_{1- δ}P_δ(0 <α ≦ 1, 0 ≦ β <
1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ ≦ 1) Single crystal
A cladding layer as a barrier layer joining the layer to the light emitting layer
At this time, the composition ratio of the constituent elements is more desirable than that of the light emitting layer.
More preferably 0.1 electron volts (eV) or more,
Desirably, a room temperature bandgap of about 0.3 eV is obtained.
Set to For example, B_αIn_βGa_γAs_{1- δ}
P_δ(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α + β +
Indium-containing compound single crystal layer such as γ = 1, 0 <δ ≦ 1)
Can form the cladding layer, but the indium
In general, the band gap is reduced
A cladding that exhibits sufficient barrier action on the light-emitting layer
It may not be possible to configure the layers. Direct
Or any transition (trans)
position) type B_αAl_βGa_γAs _{1- δ}P_δSimple connection
The cladding layer can also be composed of a crystal layer.

In particular, the range of 4.538 ° to 5.450 °
B that can take the lattice constant_αGa_γP (0 <α ≦ 1,0
≦ γ <1, α + γ = 1), BP or BAs or
BAs _1-XP_XMixed crystal (lattice constant 4.538Å to 4.777)
The cladding layer lattice-matched to the buffer layer composed of
There are advantages that can be achieved. In addition, B_αAl_βP (0 <α ≦
1, 0 ≦ β <1, α + β = 1) or B_αAl_βAs
BP or BAs or BAs_1-XP_XConsisting of mixed crystals
A cladding layer lattice-matched to the buffer layer can be formed. example
According to the MOCVD growth means, B_αGa_γP (0 <
α ≦ 1, 0 ≦ γ <1, α + γ = 1) indicates significant gas phase association
(Polymerization) A strong Lewis (Lewi) causing reaction
s) acidic trimethylaluminum ((CH_Three)_ThreeAl)
Is not used as a raw material.
Stable composition compared to III-V compound semiconductor
There is an advantage that you can grow with. Also, B_αGa_γAs
(0 <α ≦ 1, 0 ≦ γ <1, α + γ = 1) to BP
Or BAs or BAs_1-XP_XBuffer layer composed of mixed crystals
And a cladding layer that lattice-matches with. On the other hand,
Bandwidth of elemental (BAs) at room temperature is estimated to be about 1.2 eV
("Semiconductor Chemistry", p. 110). Hin
The room temperature bandgap of gallium arsenide (GaAs) is 1.43 eV.
Measured (Iwao Teramoto, “Semiconductor Device”),
Therefore, B_αGa _γAs (0 <α ≦ 1, 0 ≦ γ <1, α
+ Γ = 1) The allowable band gap at room temperature can be about 1.2 eV or less.
It is estimated that it is 1.43 eV or less above. Therefore B
_αGa_γAs is particularly suitable for light-emitting layers that emit short-wavelength visible light.
To form a cladding layer sufficient to exhibit
There are difficulties. Therefore, in the third embodiment of the present invention,
Is B as a constituent material of the cladding layer._αAl_βGa_γA
s_{1- δ}P_δ(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α
+ Β + γ = 1, 0 <δ ≦ 1), and especially B_αGa _γ
P (0 <α ≦ 1, 0 ≦ γ <1, α + γ = 1)
And a metal layer.

The gallium phosphide nitride according to the fourth embodiment of the present invention
Um (GaN_ZP_1-Z: 0 <Z <1) The lattice constant is cubic
Considering that the lattice constant of crystalline GaN is 4.510 °
Then, it is more than 4.510 ° and less than 5.450 °. one
On the other hand, B constituting the above-mentioned cladding layer_αAl_βGa_γAs
_{1- δ}P_δ(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α +
β + γ = 1, 0 <δ ≦ 1) Possible lattice constant of single crystal layer
Is equal to or greater than 4.538 ° (the lattice constant of BP).
5.661 ° (the lattice constant of AlAs)
It is an enclosure. That is, GaN_ZP_1-Z(0 <Z <1) and B_αA
l_βGa_γAs_δP _{1- δ}(0 <α ≦ 1, 0 ≦ β <1, 0
≦ γ <1, α + β + γ = 1, 0 <δ ≦ 1)
Can be taken to coincide with each other. Therefore, the light emitting layer
GaN_ZP_{1 -Z}(0 <Z <1), the lattice constant
B whose number is more than 4.510 and less than 5.450_αA
l_βGa_γAs_{1- δ}P_δLight emission lattice-matched to cladding layer
A layer is obtained. The crystal layer that lattice-matches with the cladding layer is
Crystal defects such as misfit dislocations due to lattice mismatch
Good quality with low densities. From this, the cladding
GaN lattice matched to layer_ZP_1-Z(0 <Z <1) crystalline layer
Can form a light-emitting layer with excellent crystallinity,
III-nitride semiconductor light-emitting device having a light-emitting layer
There are advantages.

On the other hand, for example, gallium arsenide nitride (GaN)
_ZAs_1-Z: 0 <Z <1) is determined by the nitrogen composition ratio (=
Depends on Z), exceeds 4.510Å and not 5.653Å
Is full. Therefore, the above GaN_ZP_1-Z(0 <Z <1)
Same as GaN_ZAs_1-ZFrom B_αAl_βGa_γAs
_{1- δ}P_δ(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α +
β + γ = 1, 0 <δ ≦ 1)
A combined light emitting layer can be formed. However, standard conditions (0 ° C,
Energy generated at 1 atm (= ΔH)₀)
For example, ΔH of GaN₀Is -26.2 kcal / mol
(Kcal / mol), whereas ΔH of GaAs
₀Is -19.5 kcal / mol (Japanese Unexamined Patent Publication No.
No. 53487). Therefore, GaN is compared to GaAs.
It can be formed more easily. For this reason, this thermodynamic feature
Depending on the difference in the properties, the desired
GaN with elemental composition ratio (= 1-Z)_ZAs_1-ZStabilize mixed crystals
Difficult to form. Conversely, ΔH of GaP₀Is -29.
2kcal / mol and ΔH of GaN₀Less than. Follow
GaN having a controlled phosphorus composition ratio (= 1-Z)
_ZP _1-Z(0 <Z <1) can be easily obtained, and
GaN difficult to control_ZAs_1-ZCompare with (0 <Z <1)
Thus, there is an advantage that the light emitting layer can be formed stably.

The light emitting layer is an undoped GaN _Z P ₁ -Z (0 <Z <) in which no impurity is intentionally added.
1) It can be composed of layers. Further, it can be constituted by a GaN _Z P _{1 -Z} layer doped with p-type and n-type impurities. As with obtaining an n-type or p-type buffer layer or cladding layer,
Beryllium (Be), magnesium (Mg) and zinc (Z
n) can be used as a p-type dopant. Examples of the n-type dopant include Group IV elements such as Si and tin (Sn) or V-group elements such as sulfur (S), selenium (Se), and tellurium (Te).
Group I elements can be used. Amphoteric impurities such as carbon (C) can also be used as dopants. In the light emitting layer, for example, LE
It is preferable that impurities are added to D so as to exhibit a carrier concentration that does not cause a sudden increase in the forward voltage (Vf). The carrier concentration is generally 5 × 10
^{A range of 16} cm ⁻³ or more and 5 × 10 ¹⁹ cm ⁻³ or less is suitable.
A carrier concentration within this range can be realized without doping a large amount of impurities. Therefore, it is possible to suppress expansion and contraction of the lattice of GaN _Z P _1-Z crystal layer due to the atomic radius of the difference between the constituent elements of the doping impurity and GaN _Z P _1-Z layer,
A good quality light emitting layer can be provided without disturbing the lattice matching with the cladding layer. If a large amount of impurities are doped to obtain a high carrier concentration exceeding about 5 × 10 ¹⁹ cm ⁻³ , lattice distortion may occur in the GaN _Z P _{1 -Z} layer. If strain occurs, the lattice matching with the cladding layer cannot be maintained, which is inconvenient for obtaining a light emitting layer having excellent crystallinity.

The GaN _Z P _{1 -Z} light emitting layer can be grown by metal organic chemical vapor deposition (MOCVD), like the buffer layer and the cladding layer. Ammonia (N
H ₃ ), hydrazine (H ₂ NNH ₂ ) and the like can be used.
As the group V element source, a raw material having a weak Lewis basicity is preferred in order to reduce the association reaction with the group III element source. Further, the GaN _Z P ₁ -Z light emitting layer is formed of a hydride (hyd).
(ride) It can be grown by vapor phase growth means such as vapor phase epitaxy and molecular beam epitaxy. The conductivity type of the light emitting layer can be either n-type or p-type. A cladding layer,
A light emitting portion having a pn junction type DH structure can be constituted by a light emitting layer having the same conductivity type as any of the upper and lower cladding layers. The light emitting layer also has a III-V compound semiconductor layer constituting a cladding layer as a barrier layer, and has a GaN _Z P _{1 -Z}
Single quantum well structure (SQ)
W) or a multiple quantum well structure (MQW). In addition, a single or multiple quantum well structure and a strained superlattice (strain) arranged below the lower cladding layer side.
The light-emitting layer can also be composed of both a laminated structure and a d-layer super-lattice structure (US Pat. No. 6,153,894). From the stacked structure consisting of both the strained superlattice structure and the quantum well structure,
There is an advantage that a light emitting layer including a quantum well structure having excellent crystallinity can be formed based on the relaxation effect of lattice strain due to the strained superlattice structure (US Pat. No. 6,153,894 described above).

In the fifth embodiment of the present invention, a group III nitride semiconductor light emitting device is formed using an n-type or p-type silicon (Si) single crystal having a plane orientation of {111} as a substrate. A high-resistance {111} -Si single crystal can also be used as a substrate, but low conductivity is disadvantageous for forming an ohmic electrode with low contact resistance on the back surface of the substrate.単 1 of Si single crystal
Si atoms are densely present in the {100} crystal plane as compared to the {100} crystal plane. Therefore, boron (B), phosphorus (P), or arsenic (A) constituting a buffer layer such as a low-temperature buffer layer is used.
Diffusion and penetration of s) into the Si single crystal are effectively suppressed. Thereby, the inversion of the conductivity type of the Si single crystal substrate due to the intrusion of the constituent elements of the buffer layer can be prevented. Further, since the surface of the Si substrate can be prevented from being irregularly uneven due to the erosion of the constituent elements of the buffer layer, the effect of obtaining a buffer layer having a flat surface can be obtained.

The low-temperature buffer layer is made of B_αAl_βGa_γAs_1-Y
P_Y(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α + β +
γ = 1, 0 ≦ Y ≦ 1), but aluminum
A low-temperature buffer layer containing aluminum (Al) is provided in contact with the Si substrate surface.
The surface of the Si substrate due to the erosion of aluminum (Al).
The flatness of the surface is lost. Therefore, a low-temperature buffer layer is preferable.
Is B_αGa_γIn_δAs_1-YP_Y(0 <α ≦ 1, 0 ≦ γ
<1, 0 ≦ δ <1, α + γ + δ = 1, 0 ≦ Y ≦ 1)
Constitute. B_αGa_γIn_δAs_1-YP_YFrom the crack
B which forms a layer_αAl_βGa_γAs_{1- δ}P_δ(0 <α ≦
1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ
≦ 1) A low-temperature buffer layer lattice-matched with the single crystal layer can be formed
There are advantages. In addition, in particular, the number of constituent elements has been reduced,
B that can grow easily_αGa_γAs_1-YP_Y(0 <α ≦ 1,0
≦ γ <1, α + γ = 1, 0 ≦ Y ≦ 1)
The number range is 4.538Å (corresponding to the lattice constant of BP).
You. 5.653Å (equivalent to the lattice constant of GaAs)
I do. ), The Si single crystal (lattice constant 5.4)
31Å) Advantages in forming a low-temperature buffer layer that is lattice-matched
There is. For example, the boron composition ratio (= α) is set to 0.02.
B_0.02Ga_0.98P (JP-A-11-266006)
B) with boron content ratio (= α) of 0.25_0.25G
a _0.75As (JP-A-11-260720) to S
A low-temperature buffer layer lattice-matched to the i-single crystal can be formed. low temperature
The buffer layer can have the same lattice constant as the Si single crystal.
When composed of a semiconductor material that lattice-matches with a single crystal, the lattice
High quality buffer layer with few crystal defects due to mismatch
There is an advantage to be taken. Therefore, a good quality
There is an advantage that a pad layer can be laminated.

B _α Ga _γ As _1-Y P _Y (0 <α ≦ 1, 0 ≦
The low-temperature buffer layer composed of γ <1, α + γ = 1, 0 ≦ Y ≦ 1) is preferably composed mainly of an amorphous material in an as-grown state. The low-temperature growth layer mainly composed of amorphous has a particularly effective effect in reducing the lattice mismatch with the Si single crystal substrate. Therefore, it is preferable that the growth temperature of the low-temperature buffer layer be a low temperature at which an amorphous layer can be obtained. In general, the thickness of the low-temperature buffer layer is desirably about several tens to several hundreds of nm. The low-temperature buffer layer having a thickness equal to or greater than the thickness that prevents the passage of carriers due to the tunnel effect is preferably doped with an impurity capable of providing the same conductivity type as the substrate. For example, a buffer layer may be formed by overlaying a high-temperature buffer layer grown at a higher temperature than a polycrystalline layer or a single-crystal layer can be obtained on the low-temperature buffer layer. It is not necessary to form the low-temperature buffer layer and the high-temperature buffer layer from the same material.However, in forming the buffer layer from the multilayer structure, the conduction type of each constituent layer constituting the buffer layer is the same as that of the substrate. It is preferred to do so.

[0037]

According to the present invention, a substrate made of a single crystal and an I-containing film containing boron (B) and arsenic (As) or phosphorus (P) provided on the surface of the substrate are provided.
A III-nitride semiconductor light-emitting device comprising a low-temperature buffer layer made of a II-V compound semiconductor, and a light-emitting portion having a heterojunction structure of a light-emitting layer and a cladding layer provided on the buffer layer. Boron (B) of the present invention provided above
A crystal layer composed of a group III-V compound semiconductor single crystal layer containing phosphorus and phosphorus (P) is excellent in the electrical activation rate of carriers due to its low ionic bonding property, so that a low-resistance cladding layer is provided. Having.

B _α A grown at a higher temperature than the low-temperature buffer layer
1 _β Ga _γ As _{1− δ} P _δ (0 <α ≦ 1, 0 ≦ β <1, 0
≦ γ <1, α + β + γ = 1, 0 <δ ≦ 1) A crystal layer made of a single crystal is particularly low-resistance and excellent in crystallinity in an LED, which can diffuse an element driving current over a wide range of a light emitting surface. Has the effect of providing a cladding layer.

In addition, B _α Ga _γ P (0 <α ≦ 1, 0 ≦ γ
The crystal layer composed of <1, α + γ = 1) has an effect of providing a clad layer having excellent crystallinity and a stable composition ratio, which can be easily grown.

The GaN _Z P _{1 -Z} (0 <Z <1) crystal layer is excellent in crystallinity because of lattice matching with the cladding layer, and therefore has an effect of providing a light emitting layer that is superior in providing high output light emission. .

An n-type or p-type silicon (Si) single crystal substrate having a plane orientation of {111} has an effect of suppressing penetration of elements constituting the buffer layer into the substrate. Also, B _α
Ga _γ As _1-Y P _Y (0 <α ≦ 1, 0 ≦ γ <1, α + γ =
1, 0 ≦ Y ≦ 1 low-temperature crystal layer was formed from) is, Si single crystal substrate and the _{B α Al β Ga γ As 1-} δ P δ (0 <α ≦ 1,
0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ ≦
1) Since lattice matching can be achieved with both the single crystal cladding layer, the lattice mismatch with the Si single crystal is alleviated, and an effect of providing a cladding layer having excellent crystallinity on a substrate is provided.

[0042]

(Example 1) Hereinafter, a group III nitride semiconductor L
The present invention will be specifically described using an ED as an example. FIG. 1 shows a schematic cross-sectional view of an LED 10 according to the present embodiment.

As the substrate 101, a boron (B) -doped p-type Si single crystal having a plane orientation of {111} was used. On the substrate 101, boron-gallium phosphide (B _0.02 Ga) lattice-matched with a Si single crystal (lattice constant: 5.431 °)
_A low temperature buffer layer 102 of _0.98 P) was deposited. The low-temperature buffer layer 102 was grown at 350 ° C. by a normal pressure MOCVD method based on triethylboron ((C ₂ H ₅ ) ₃ B) / phosphine (PH ₃ ) / hydrogen (H ₂ ). The layer thickness of the low-temperature buffer layer 102 was 15 nm.

On the surface of the low-temperature buffer layer 102, a trimethyl gallium ((CH ₃ ) ₃ Ga) / PH ₃ / H ₂ system normal pressure MOC
According to the VD method, p-type boron-gallium phosphide (B _0.98 Ga) doped with magnesium (Mg) at 1000 ° C.
_0.02 P) single crystal layer (lattice constant: 4.557 °) was laminated as the lower cladding layer 103. Bis-cyclopentadienyl magnesium (b
is- a _{(C 5 H 4) 2 Mg} ) was used. Lower cladding layer 1
03 had a carrier concentration of 7 × 10 ¹⁸ cm ⁻³ . The layer thickness was 1.8 μm.

On the lower cladding layer 103, a magnesium-doped p-type gallium phosphide nitride (GaN _0.95 P _0.05 ) layer having a phosphorus composition ratio of 0.05 (= 5%) was laminated as the light emitting layer 104. Cubic crystal G forming the light emitting layer 104
The lattice constant of the aN _0.95 P _0.05 layer was 4.557 °, and was lattice-matched to the lower cladding layer 103. The light-emitting layer 104 is made of trimethylgallium ((CH ₃ ) ₃ Ga).
/ PH ₃ / Ammonia (NH ₃ ) / H ₂ normal pressure MOCVD
It was grown at 950 ° C. by the method. The carrier concentration of the light emitting layer 104 was 3 × 10 ¹⁷ cm ⁻³ , and the layer thickness was 300 nm.

On the surface of the light emitting layer 104, (C ₂ H ₅ ) ₃
The upper cladding layer 105 was laminated at 1000 ° C. by a B / (CH ₃ ) ₃ Ga / PH ₃ / H ₂ normal pressure MOCVD method. The upper cladding layer 105 is made of Si-doped n-type B _0.98 Ga
_It was composed of a _0.02 P single crystal layer (with a lattice constant of 4.557 °). The upper cladding layer 105 was also formed of a single crystal layer lattice-matched to the light emitting layer 104. The carrier concentration of the upper cladding layer 105 was set to 8 × 10 ¹⁷ cm ⁻³ , and the layer thickness was set to 250 nm. The lower clad 103, the light emitting layer 104, and the upper clad layer 105 constitute a light emitting section 106 having a pn junction type double hetero junction structure of a lattice matching system.

On the back surface of the p-type Si single crystal substrate 101, a p-type ohmic (Ohmi) made of aluminum (Al) is provided.
c) The electrode 109 was formed. The upper cladding layer 10
In the central part of the surface of No. 5, gold-germanium (Au-G
e) An n-type ohmic electrode 108 made of an alloy was arranged. The diameter of the n-type ohmic electrode 108 was 130 μm. After that, the Si single crystal used as the substrate 101 was changed to [211].
Cut parallel and perpendicular to the direction, one side of 300μ
The LED chip (chip) 10 was set to m.

LE between both ohmic electrodes 108-109
A forward current for D drive was passed. Current-voltage (IV)
(Characteristics) showed normal rectification characteristics based on good pn junction characteristics of the light emitting section 106. The forward voltage (Vf) obtained from the IV characteristics was 3.1 V (forward current = 20 mA). The reverse voltage is 5 V (reverse current = 10 μA)
That's all. The center wavelength of light emission when a forward current of 20 mA was passed through the manufactured LED was 460 nm.
The half width of the emission spectrum was 20 nm. The light emission intensity in a chip state measured using a general integrating sphere is 16 microwatts (μW), and II of high light emission output
A Group I nitride semiconductor LED has been provided.

(Example 2) The present invention will be specifically described by taking a group III nitride semiconductor LED having a different structure from that of Example 1 as an example. FIG. 2 is a schematic cross-sectional view of the LED 20 according to the present embodiment. The same functional layers as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG.

Boron (B) doped with p-type plane orientation of $ 11
A low-temperature buffer layer 102 made of undoped boron phosphide (BP) was deposited on a substrate 101 made of 1% Si single crystal. The low-temperature buffer layer 102 is made of (C ₂ H ₅ ) ₃ B / PH ₃
It was grown at 350 ° C. by a / H ₂ system normal pressure MOCVD method. The layer thickness of the low-temperature buffer layer 102 was 5 nm.

On the low-temperature buffer layer 102, (C ₂ H ₅ ) ₃ B
/ PH ₃ / H ₂ Atmospheric pressure at 950 ° C.
A high temperature buffer layer 107 composed of a p-type boron phosphide (BP) layer doped with g was laminated. Bis-cyclopentadienyl magnesium (b
is- a _{(C 5 H 4) 2 Mg} ) was used. High temperature buffer layer 107
Was set to 7 × 10 ¹⁸ cm ⁻³ . Layer thickness is 30
It was set to 0 nm. According to a general transmission electron microscope (TEM) observation, the internal region extending 250 nm above the junction interface between the high-temperature buffer layer 107 and the low-temperature buffer layer 102 is mainly composed of BP polycrystal. Was. It was found that the upper surface region was mainly composed of a single crystal.

On the high temperature buffer layer 107, the above MOCV
The lower cladding layer 103 made of boron phosphide (BP) single crystal (lattice constant: 4.538 °) was laminated using D growth means. The BP single crystal layer forming the lower cladding layer 103 was grown at 950 ° C., which was higher than the low temperature buffer layer 102. The lower cladding layer 103 is formed of a normal hole (Hal
l) The carrier concentration measured by the effect method is set to 8 × 10 ¹⁸
cm ^-3 and a single crystal layer having a mobility at room temperature of 30 cm ² / V · s. The layer thickness was 2.2 μm.

On the lower cladding layer 103, a thickness of about 5
A light emitting layer 104 made of p-type gallium nitride phosphide (GaN _0.97 P _0.03 ) doped with Mg and having a thickness of 00 nm was laminated. The lattice constant of the cubic light emitting layer 104 was 4.538 °, and the lower cladding layer 103 and the light emitting layer 104 had a lattice matching relationship. The doping source magnesium _{(Mg) bis- (C 5 H} 4) using ₂ Mg. The growth temperature was set at 900 ° C. The carrier concentration of the light emitting layer 104 is 5
× 10 ¹⁷ cm ^-3 .

On the surface of the light emitting layer 104, (C ₂ H ₅ ) ₃
The upper cladding layer 105 was laminated at 1050 ° C. by a B / PH ₃ / H ₂ system normal pressure MOCVD method. Upper cladding layer 10
Reference numeral 5 is an Si-doped n-type boron phosphide (BP) single crystal layer (with a lattice constant of 4.538 °). The upper cladding layer 105 was lattice-matched to the GaN _0.97 P _0.03 light emitting layer 104. The carrier concentration of the upper cladding layer 105 is 2 × 1
0 ¹⁸ cm ^-3 and a layer thickness of 150 nm. The lower clad 103, the light emitting layer 104, and the upper clad layer 105 constitute a light emitting section 106 having a pn junction type double hetero junction structure of a lattice matching system.

On the back surface of the p-type Si single crystal substrate 101, a p-type ohmic (Ohmi) made of aluminum (Al) is provided.
c) The electrode 109 was formed. The upper cladding layer 10
The n-type ohmic electrode 108 made of Au.Ge alloy (95% by mass of Au.5% by mass of Ge)
Was placed. The diameter of the p-type ohmic electrode 108 is 110
μm. Thereafter, the Si single crystal serving as the substrate 101 was cut in a direction parallel and perpendicular to the [211] direction, thereby forming an LED chip (chip) 10 having a side of 260 μm.

LE between the ohmic electrodes 108 to 109
D drive current was passed. Current-voltage (IV characteristics)
Showed normal rectification characteristics based on good pn junction characteristics brought about by the light emitting unit 106 of the lattice matching system. I
The forward voltage (Vf) obtained from the -V characteristic was 3.1 V (forward current = 20 mA). The reverse voltage is 5
V (reverse current = 10 μA) or more. L made
When an operating current of 20 milliamperes (mA) was passed through the ED in the forward direction, blue-violet light having an emission center wavelength of 420 nm was emitted. The half width of the emission spectrum was 23 nm. The emission intensity in a chip state measured using a general integrating sphere is 11 microwatts (μW),
A III-nitride semiconductor LED with high light output has been provided.

[0057]

According to the present invention, a substrate made of a single crystal, and boron (B) and arsenic (As) provided on the surface of the substrate are provided.
Alternatively, III including a buffer layer including a low-temperature buffer layer made of a III-V compound semiconductor containing phosphorus (P), and a light emitting portion having a heterojunction structure of a light emitting layer and a cladding layer provided on the buffer layer. In the group nitride semiconductor light emitting device, the cladding layer provided on the buffer layer is composed of a group IIIV compound semiconductor single crystal layer containing boron (B) and phosphorus (P), and the light emitting layer is formed of a cladding layer. Lattice matched to
Since it is made of a group III nitride semiconductor layer containing nitrogen (N) and a group V element other than nitrogen, a pn junction type light emitting portion can be formed from a high quality semiconductor crystal layer with few crystal defects caused by lattice mismatch. Having excellent rectification characteristics and providing high output light emission II
A group I nitride semiconductor light emitting device can be provided.

Further, the clad layer is set at a higher temperature than the low-temperature buffer layer.
B grown in_αAl_βGa_γAs_{1- δ}P_δ(0 <α ≦
1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0 <δ
≦ 1) Since the light-emitting layer is composed of a single crystal,
Impurity due to low degree of ionic bonding
Including a clad layer with high electrical activation rate and excellent conductivity
Light emitting portion can be manufactured.

The cladding layer is made of B _α Ga _γ P (0 <α
.Ltoreq.1, 0.ltoreq..gamma. <1, .alpha. +. Gamma. = 1), it is possible to form a cladding layer having particularly excellent conductivity and lattice-matching to the light emitting layer.

Gallium phosphide nitride (GaN
_{When the} light emitting layer is formed from _Z P _{1 -Z} : 0 <Z <1), there is an effect that the light emitting layer lattice-matched to the cladding layer can be easily formed.

Further, an n-type or p-type Si single crystal having a plane orientation of {111} is used as a substrate, and a low-temperature buffer layer provided on the substrate is B _α Ga _γ As _1-Y P _Y (0 <α ≦ 1 , 0 ≦ γ <
1, α + γ = 1, 0 ≦ Y ≦ 1), a low-temperature buffer layer lattice-matched to the Si single crystal is provided, and an upper layer having excellent crystallinity is provided on the low-temperature buffer layer. Thus, it is possible to provide a group III nitride semiconductor light emitting device having a high light emission output.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an LED according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of an LED according to a second embodiment of the present invention.

[Explanation of symbols]

 10, 20 LED 101 Si single crystal substrate 102 Low temperature buffer layer 103 Lower cladding layer 104 Light emitting layer 105 Upper cladding layer 106 Light emitting section 107 High temperature buffer layer 108 n-type ohmic electrode 109 p-type ohmic electrode

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F041 AA04 CA04 CA34 CA49 CA57 CA65 CA85 CA87 5F045 AA04 AB17 AB18 AB19 AC01 AC09 AD07 AD13 AD14 AF03 BB17 CA02 CA10 DA53 5F073 AA55 CA07 CB04 CB19 DA05 EA24 EA29

Claims (12)

[Claims] A substrate comprising a single crystal and a low-temperature buffer layer comprising a group III-V compound semiconductor containing boron (B) and arsenic (As) or phosphorus (P) provided on the surface of the substrate. In a III-nitride semiconductor light emitting device including a buffer layer and a light emitting portion having a heterojunction structure of a light emitting layer and a cladding layer provided on the buffer layer, the cladding layer is formed of boron (B) and phosphorus (P). And the light-emitting layer is composed of a group III nitride semiconductor layer containing nitrogen (N) lattice-matched to the cladding layer and a group V element other than nitrogen. A group III nitride semiconductor light-emitting device, characterized by: 2. The method of claim 1, wherein the cladding layer is grown at a higher temperature than the low-temperature buffer layer, and has a general formula B _α Al _β Ga _γ As _{1- δ} P _δ (0 <
α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0
3. The group III nitride semiconductor light emitting device according to claim 1, wherein the group III nitride semiconductor light emitting device is formed of a conductive group III-V compound semiconductor single crystal represented by <δ ≦ 1). 3. The method according to claim 1, wherein the cladding layer has a general formula B _α Ga _γ P (0 <
3. A group III nitride semiconductor light emitting device according to claim 2, comprising a conductive group III-V compound semiconductor single crystal represented by α ≦ 1, 0 ≦ γ <1, α + γ = 1). . 4. The light emitting layer is made of gallium phosphide nitride (GaN _Z).
4. The group III nitride semiconductor light emitting device according to claim 1, wherein P _{1 -Z} : 0 <Z <1). 5. The group III according to claim 1, wherein the substrate is an n-type or p-type silicon (Si) single crystal having a plane orientation of {111}. Nitride semiconductor light emitting device. 6. The low-temperature buffer layer is formed of B _α Ga _γ As _1-Y P _Y (0 <
6. The group III nitride semiconductor light emitting device according to claim 1, wherein α ≦ 1, 0 ≦ γ <1, α + γ = 1, and 0 ≦ Y ≦ 1). 7. A substrate containing boron (B) and arsenic (As) or phosphorus (P) on a surface of a substrate made of a single crystal.
A method for manufacturing a group III nitride semiconductor light emitting device, comprising: forming a buffer layer including a low-temperature buffer layer made of a group V compound semiconductor, and forming a light emitting portion having a heterojunction structure of a cladding layer and a light emitting layer on the buffer layer In the above, the cladding layer is made of boron (B).
Group nitride semiconductor layer comprising nitrogen (N) and a group V element other than nitrogen for lattice-matching the light emitting layer to the cladding layer A method of manufacturing a group III nitride semiconductor light emitting device, comprising: 8. The general formula B _α Al _β Ga _γ As _{1- δ} P _δ (0 <) wherein the cladding layer is grown at a higher temperature than the low temperature buffer layer.
α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, α + β + γ = 1, 0
The method for manufacturing a group III nitride semiconductor light emitting device according to claim 7, comprising a conductive group III-V compound semiconductor single crystal represented by <δ≤1). 9. The method of claim 1, wherein the cladding layer has a general formula B _α Ga _γ P (0 <
9. A group III nitride semiconductor light emitting device according to claim 8, comprising a conductive group III-V compound semiconductor single crystal represented by α ≦ 1, 0 ≦ γ <1, α + γ = 1). Manufacturing method. 10. The light emitting layer is made of gallium nitride phosphide (GaN).
_The method for manufacturing a group III nitride semiconductor light-emitting device according to any one of claims 7 to 9, wherein Zp1 _-Z : 0 <Z <1). 11. The group III according to claim 7, wherein the substrate is an n-type or p-type silicon (Si) single crystal having a plane orientation of {111}. A method for manufacturing a nitride semiconductor light emitting device. 12. A low-temperature buffer layer comprising a B _α Ga _γ As _1-Y P _Y (0
12. The group III nitride semiconductor light emitting device according to claim 7, wherein <α ≦ 1, 0 ≦ γ <1, α + γ = 1, and 0 ≦ Y ≦ 1). Production method.