JP2003046120A - Light-emitting device, laminated structure therefor, lamp and light source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To present the constitution of a boron-containing III-V compound semiconductor layer to be stably given a light-emitting layer composed of a gallium-containing III-V compound semiconductor layer of a good quality on a single crystal substrate of silicon, etc. SOLUTION: A laminated structure for a light-emitting is provided with a single crystal substrate, a buffer layer laminated on the substrate, a barrier layer laminated on the buffer layer and composed of a III-V compound semiconductor containing boron, and the light-emitting layer composed of the gallium- containing III-V compound semiconductor layer. The barrier layer is composed of a composition inclination layer which has a boron composition ratio lattice- matched with the buffer layer on a surface facing the buffer layer, which has a boron composition ratio lattice-matched with the light-emitting layer and which is composed of the boron-containing III-V compound semiconductor obtained by inclining the boron composition ratio in the increasing direction of a layer thickness.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to gallium (Ga).
III-V group compound semiconductor containing (gallium-containing III-
A laminated structure for a light emitting device, which includes a light emitting layer made of a V group compound semiconductor) and a barrier layer made of a III-V group compound semiconductor containing boron (B) (boron-containing III-V group compound semiconductor), and the same. The present invention relates to a technique for forming a light emitting device, a lamp and a light source from a laminated structure.

[0002]

2. Description of the Related Art Conventionally, II containing gallium (Ga)
As a light-emitting element including a group IV compound semiconductor as a light-emitting layer, for example, a green band light-emitting diode (LED) including gallium phosphide (GaP) as a light-emitting layer is known (Iwao Teramoto, “Semiconductor Device”). Introduction ”(see Baifukan Co., Ltd., first edition issued March 30, 1995, pp. 118-121). As another conventional example, gallium arsenide phosphide (GaAs _1-X P _X : 0 ≦ X ≦ 1) Yellow band LEDs are known (above-mentioned "Introduction to Semiconductor Devices", 114-11).
(See page 6). Gallium-containing III that has been put to practical use
Each of the light-emitting devices including the group-V compound semiconductor layer as a light-emitting layer is usually composed of a laminated structure including a light-emitting portion having a pn junction single (homo) junction structure.

Boron phosphide (BP), which is a type of III-V compound semiconductor, has a low ionic bond level of 0.006 (see Phillips, "Semiconductor Coupling Theory" (Yoshioka Shoten Co., Ltd., July 1985). Published on 25th, 3rd printing), 49-51
(See page), in particular, a p-type conductive semiconductor layer is easily obtained. Such a feature of boron phosphide (BP) acts dominantly in, for example, simply forming a pn junction structure. Therefore, conventionally, boron phosphide-based III-V
A technique of forming a light emitting element such as a light emitting diode (LED) or a laser diode (LD) from a laminated structure including a group compound semiconductor layer is disclosed (Japanese Patent Laid-Open No. 2-28).
8388 publication). Conventionally, a laminated structure including a boron phosphide-based semiconductor layer is, for example, III-V such as gallium phosphide (GaP) and gallium nitride (GaN).
A group compound semiconductor single crystal is used as a substrate (
JP-A-2-275682 / Japanese Patent No. 280969
No. 0 and JP-A-10-247745). Further, silicon (Si) single crystal (silicon) is known as another substrate material (US Pat. No. 6,069,0).
21). Silicon carbide (SiC) is also used as a substrate material (see the above-mentioned Japanese Patent No. 2809690).

Conventionally, boron phosphide-based semiconductor layers have been used as various functional layers. For example, JP-A-10
The invention described in No. 242569 discloses a current confinement type green laser diode (LD) including a boron phosphide layer as a current blocking layer. There is also a known example in which a laminated structure is provided with a boron phosphide layer as a contact layer for forming an ohmic electrode (see JP-A-10-242568). An LED provided with a boron phosphide layer as a buffer layer
Is also known (see Japanese Patent Laid-Open No. 10-242514). In particular, there is an example in which a so-called low-temperature buffer layer formed at a relatively low temperature is composed of a boron phosphide-based semiconductor layer in order to better alleviate the lattice mismatch between the substrate material and the laminated structure constituting layer. Known (see US Pat. No. 6,069,021 above). For example, on a silicon (Si) or gallium phosphide (GaP) single crystal substrate, boron phosphide / gallium (B _X Ga _1-X P: 0 ≦ X ≦
1) or boron phosphide / indium (B _X In _1-X P: 0
A technique of forming a buffer layer from ≦ X ≦ 1) is disclosed (see Japanese Patent Laid-Open No. 11-266006).

On the other hand, conventionally, the band gap of boron phosphide (BP) at room temperature is said to be about 2 eV (R
CA Review, 25 (1964), 159-16.
Page 7, Z. anorg. allg. chem. , 34
9 (1967), pp. 151-157, and the above-mentioned "Introduction to Semiconductor Devices", page 28). A technique for forming a BP-based mixed crystal having a higher bandgap using boron phosphide having a bandgap as low as about 2 eV as a base material is also disclosed. For example,
A forbidden band of 2.7 eV from a superlattice structure of an undoped aluminum nitride / gallium mixed crystal (Ga _0.5 Al _0.5 N) thin layer (layer thickness = 1 nm) and a boron phosphide thin layer (layer thickness = 1 nm). The width has been obtained (see above-mentioned JP-A-1
0-247745). Also, for example, Ga _0.25 A
l _0.25 B _0.50 N _0.60 P _{0.40 As a} quaternary mixed crystal, a semiconductor layer having a band gap of 2.7 eV was obtained (Japanese Patent Laid-Open No. 2-28).
8371).

[0006]

Problems to be Solved by the Invention Gallium-containing III-V
In an LED having a group compound semiconductor layer as a light emitting layer, if the light emitting portion has a double (DH) structure instead of the conventional single (SH) structure, a "light confinement" effect or a "carrier (carrier)" Due to the "confinement" effect, the emission intensity is increased, and it is expected that a high-brightness LED is realized (see "Introduction to Semiconductor Devices", pages 124 to 126). For example, means for forming a DH structure light emitting part by joining a GaAlBNP ternary mixed crystal having a forbidden band width increased by the above-mentioned conventional means as a barrier layer to the light emitting layer is also considered. However, it is well known that it is difficult to maintain a stable composition of constituent elements of a multi-element mixed crystal such as a quinary mixed crystal in which composition of constituent elements is stable (above-mentioned “Introduction to Semiconductor Devices”, 24). See page).

Further, in the conventional technique for obtaining a semiconductor layer having a higher bandgap using boron phosphide having a bandgap of about 2 eV as a base material, ultrathin films of about several nm are alternately laminated alternately. Therefore, a superlattice structure must be obtained, and a complicated and redundant film forming operation is required to stably control the layer thickness and composition of the ultrathin film. In addition, a special film forming apparatus for forming a superlattice structure is also required (see Japanese Patent Laid-Open No. Hei 2).
-288371).

Recently, the complexity of the conventional growth operation is avoided.
The simple and easy vapor phase growth method that can be used, resulting in a higher temperature than ever before at room temperature.
A technology for obtaining boron phosphide (BP) with a wide band gap was developed.
ing. Also, boron phosphide having a high band gap at room temperature
Alternatively, a mixed crystal composed of the base material is used as a barrier (cla).
d) gallium arsenide phosphide (GaAs)
_1-XP_X: 0 ≦ X ≦ 1) forming a heterojunction structure with the light emitting layer
The technology to do is proposed.

However, boron-containing III-V compound semiconductors
Between the layer and the gallium-containing III-V compound semiconductor light emitting layer
Higher emission intensity even with the technology that constitutes terrorism junction
-Containing gallium II with excellent crystallinity to bring about luminescence
A junction structure for obtaining a group IV compound semiconductor light emitting layer is desired.
I was struck. That is, for example, GaAs with high emission intensity
_1-XP_XA barrier suitable for providing a light emitting device (cla)
d) Layer is composed of a boron-containing III-V group compound semiconductor
Further improvements in technology were required.

The present invention has been made to overcome the above-mentioned problems of the prior art, and is a boron-containing III-V group compound capable of stably providing a light emitting layer composed of a good-quality gallium-containing III-V group compound semiconductor layer. A structure of a semiconductor layer is presented, and a laminated structure for a light emitting device, a light emitting device, a lamp, and a boron-containing III-V compound semiconductor layer having the structure are presented.
And a light source.

[0011]

That is, the present invention is directed to a III-V group compound semiconductor containing a single crystal substrate, a buffer layer laminated on the substrate, and boron (B) laminated on the buffer layer. For a light emitting device comprising a barrier layer made of (boron-containing III-V group compound semiconductor) and a light-emitting layer made of III-V group compound semiconductor containing gallium (Ga) (gallium-containing III-V group compound semiconductor) A laminated structure for a light emitting device, which has the characteristics described in the following items (1) to (6). (1) The barrier layer has a composition ratio of boron (B) lattice-matched to the buffer layer on the surface facing the buffer layer, and boron (B) lattice-matched to the light emitting layer on the surface facing the light emitting layer (B). ) A laminated structure for a light emitting device, comprising a composition gradient layer composed of a boron-containing III-V group compound semiconductor having a composition ratio and a boron (B) composition ratio gradient in an increasing direction of the layer thickness. . (2) The light emitting layer made of a gallium-containing III-V compound semiconductor is made of the same material as the boron-containing III-V compound semiconductor forming the surface of the barrier layer facing the light emitting layer. The laminated structure for a light emitting device according to (1). (3) The light emitting layer is formed of boron arsenide phosphide / gallium ( _BY Ga).
_1-Y As _1-Z P _Z : 0 ≦ Y <1, 0 <Z ≦ 1), The laminated structure for a light-emitting element as described in (1) or (2) above. (4) A barrier layer made of a boron-containing III-V group compound semiconductor is provided on a buffer layer made of a boron-containing III-V group compound semiconductor having a composition lattice-matched to a single crystal material forming a substrate. The laminated structure for a light emitting device according to any one of (1) to (3), which is characterized. (5) The single crystal substrate is made of silicon single crystal (silicon), and the barrier layer made of a boron-containing III-V group compound semiconductor layer is formed of boron phosphide / gallium (B _X Ga _1-X P: 0 <X ≦ 1). The laminated structure for a light-emitting element according to any one of (1) to (4) above, which is configured by: (6) The single crystal substrate is made of silicon single crystal (silicon), and the barrier layer made of a boron-containing III-V group compound semiconductor layer is formed of boron phosphide / indium (B _X In _1-X P: 0 <X ≦ 1). The laminated structure for a light-emitting element according to any one of (1) to (4) above, which is configured by:

Further, the present invention is characterized in that the above laminated structure is used, and (7) the laminated structure for a light emitting device described in any one of (1) to (6) above is used. Light emitting element. (8) The light emitting device according to the above (7), which is provided with a light emitting device and an electronic component for controlling the intensity of light emitted from the light emitting device on the same single crystal substrate. (9) The light emitting device according to (8), wherein the electronic component is provided on a barrier layer made of a boron-containing III-V compound semiconductor. Further, the present invention provides (10) a lamp comprising the light emitting device according to any one of (7) to (9). (11) A light source comprising the lamp according to (10) above. I will provide a.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to the schematic sectional view of the laminated structure 1A shown in FIG. 1 as an example. Laminated structure 1A according to the first embodiment
Is, for example, {100}, {110} or {111}
The substrate 10 is made of n-type or p-type silicon having a crystal plane as a main surface.
Configure as 1. Silicon having a surface inclined from the main surface toward a specific crystal orientation can also be used as the substrate 101. For example, the substrate 101 can be made of silicon having {100} as a main surface, which has a surface inclined at an angle of several degrees to several tens of degrees with respect to the [110] crystal orientation. n-type or p-type gallium phosphide (GaP) or gallium arsenide (GaAs)
Alternatively, boron phosphide (BP) (J. Electroch
em. Soc. 120 (1973), p. p. 802
~ 806. , And U.S. Pat. No. 5,042,043)).
Available as 1.

If the conductive crystalline material is used as the substrate 101,
Depending on the electrical conductivity of the substrate 101, a positive or negative polarity ohmic electrode 10 is provided on the back surface of the substrate 101.
7 can be laid. Therefore, the conductive crystal substrate is complicated when the insulating crystal such as sapphire is used as the substrate, a part of the laminated structure is removed to expose the surface of the conductive constituent layer, and then the electrode is formed. Process (JP-A-10-321907)
(See Japanese Unexamined Patent Publication No. JP-A-2003-24035), and a convenient technical means for easily configuring a light emitting element is provided. In particular, the conductive single crystal substrate 101 having a low specific resistance, which has a resistivity of 10 milliohms (mΩ) or less, and more preferably 1 mΩ or less, has a forward voltage (so-called,
It is effective for constructing an LED that suppresses Vf) to a low level and an LD that provides stable oscillation because it has excellent heat dissipation.

Intermediate between single crystal substrate 101 and barrier layer 103
Therefore, it is desirable that the buffer layer 102 be provided.
The buffer layer 102 has, for example, the general formula B_αAl_βGa_γIn
_{1- α - β - γ}P_{1- δ}As_δ(0 <α ≦ 1, 0 ≦ β <1, 0
Table with ≦ γ <1 and 0 <α + β + γ ≦ 1, 0 ≦ δ <1)
The boron phosphide-based semiconductor described below can be preferably used. Well
For example, the general formula B_αAl_βGa_γIn_{1- α - β - γ}P
_{1- δ}N_δ(0 <α ≦ 1, 0 ≦ β <1, 0 ≦ γ <1, and
Nitrogen expressed as 0 <α + β + γ ≦ 1, 0 <δ <1)
It can be composed of a boron phosphide-based semiconductor containing (N). Preferred
Ideally, the number of constituent elements is small, and it is easy to form a binary structure.
It is composed of crystals or ternary mixed crystals. For example, monomer phosphorylation
Boron (BP), aluminum phosphide-boron mixed crystal (B_αA
l_βP: 0 <α ≦ 1, 0 ≦ β <1, and α + β = 1),
Boron phosphide / gallium mixed crystal (B_αGa_δP: 0 <α ≦
1, 0 ≦ γ <1 and α + δ = 1), or boron phosphide
・ Indium mixed crystal (B_αIn_{1- α}P: 0 <α ≤ 1) etc.
It consists of.

In particular, when the buffer layer 102 is composed of a crystal layer having a composition that lattice-matches the single crystal material forming the substrate 101, the single crystal substrate 101 and, for example, the constituent layers of the laminated structure 1A such as the barrier layer 103. There is an advantage that the lattice mismatch of is relaxed. Therefore, it is particularly effective in obtaining the barrier layer 103 or the light emitting layer 104 having excellent crystallinity. As a preferable constituent material of the buffer layer 102 for producing this effect, boron phosphide / gallium (B _0.02 Ga _0.98 P: lattice constant ≈5.431 Å) lattice-matched to silicon (lattice constant ≈5.431 Å) can be exemplified. (The above-mentioned JP-A-11-2
66006). In addition, boron phosphide / gallium (B
_0.32 Ga _0.68 P: lattice constant ≈ 5.450Å) or boron arsenide / gallium (B _0.23 Ga _0.77 As: lattice constant ≈ 5.45)
GaP single crystal (lattice constant ≈ 5.450) from 0Å)
Å) A boron-containing III-V group compound semiconductor mixed crystal layer that achieves lattice matching with the substrate can be formed (Japanese Patent Laid-Open No. 2000-22211).
(See the official gazette).

When the buffer layer 102 is composed of a thin film layer made of amorphous or polycrystalline, the substrate 101 and the barrier layer 103 are formed.
Barrier layer 1 due to the difference in the coefficient of thermal expansion between the materials constituting the
It is effective to prevent the peeling of 03 from the surface of the substrate 101. In particular, when the buffer layer 102 is made of the same boron-containing III-V group compound semiconductor material as that of the barrier layer 103, the effect of preventing peeling of the barrier layer 103 can be remarkably exhibited. Amorphous or polycrystalline B _α Al _β Ga _γ In _{1-
α - β - γ} P _{1- δ} As _δ (0 <α ≤ 1, 0 ≤ β <1, 0 ≤
The buffer layer 102 with γ <1 and 0 <α + β + γ ≦ 1, 0 ≦ δ <1 is formed by, for example, the MOCVD method (Inst. Phy).
s. Conf. Ser. , No. 129 (IOP Pu
blushing Ltd. , 1993), 157-1
(See page 62), the deposition temperature is set to a relatively low temperature of 250 ° C.
It can be formed at 750 ° C. At a low temperature of about 500 ° C. or lower, a boron-containing III-V group compound semiconductor layer mainly composed of an amorphous material is easily obtained. A polycrystalline boron-containing III-V group compound semiconductor layer is obtained in a higher temperature range of about 500 ° C to 750 ° C. The layer thickness of the thin film layer forming the amorphous or polycrystalline buffer layer 102 is preferably about 1 nm or more and 100 nm or less, and more preferably 2 nm or more and 50 nm or less. Whether the thin film layer is an amorphous layer or a polycrystalline layer can be known from, for example, analysis of a diffraction image by a general X-ray diffraction method or electron beam diffraction method.

Buffer layer 102 made of amorphous or polycrystalline
Also has a function of uniformly specifying the crystal plane that forms the barrier layer 103 that is an upper layer of the single crystal material that does not depend on the plane index of the crystal plane that forms the surface of the substrate 101. For example, if the barrier layer 103 is provided with the amorphous or polycrystalline buffer layer 102 provided on the surface of a cubic substrate of silicon or the like interposed, the crystal layer mainly composed of the {110} crystal plane is stabilized. Obtained. The crystal planes ({110} crystal planes) whose plane index is {110} are (110) and (-
1,1,0), (-1, -1,0), (1, -1,0)
Is a general term for crystal planes equivalent to (110). Buffer layer 1
02 or the crystal planes constituting the barrier layer 103 and the like are normal X
It can be identified by analyzing the line diffraction pattern or the electron beam diffraction pattern. Boron-containing I mainly composed of {110} crystal planes I
The II-V group compound semiconductor layer, for example, the boron phosphide layer can be formed in the range of approximately 750 ° C to 1200 ° C. 120
The film formation at a high temperature exceeding 0 ° C. remarkably generates pores (pits) due to the volatilization of the constituent elements of the boron-containing III-V group compound semiconductor layer, particularly the group V constituent elements, and the semiconductor having a smooth surface. It hinders stable formation of layers. A cubic zinc blende crystal type boron-containing III-V group compound semiconductor is [110]
It exhibits a clear cleavage property (see Takashi Kawatoda, “Electronics and Information Engineering Course, 12 Device Process” (January 15, 1993, first edition published by Baifukan Co., Ltd.), p. 161). Therefore, the boron-containing III-V group compound semiconductor layer having the {110} crystal plane can be easily cleaved. Therefore, for example, a laminated laser body having a crystal layer mainly composed of {110} crystal faces has an advantage that a rectangular parallelepiped laser diode having a cleavage plane as a resonance end face can be easily configured.

On the buffer layer 102, for example, the general formula B _{α
Al β Ga γ In 1- α -} β - γ P 1- δ As δ (0 <α ≦
1, 0 ≦ β <1, 0 ≦ γ <1, and 0 <α + β + γ ≦
1, 0 ≦ δ <1) or the general formula B _α Al _β Ga _γ In
_{1- α - β - γ} P _{1- δ} N _δ (0 <α ≦ 1, 0 ≦ β <1, 0 ≦
A barrier layer 103 composed of a boron-containing III-V group compound semiconductor layer represented by γ <1 and 0 <α + β + γ ≦ 1, 0 <δ <1) is provided. The barrier layer 103 is lattice-matched with the buffer layer 102 at the bonding interface with the substrate 101, and the light emitting layer 104 is provided.
It is composed of a composition gradient layer having a boron composition ratio that is lattice-matched to the light emitting layer 104 at the junction interface with. The composition gradient layer in which the barrier layer 103 is lattice-matched to both the buffer layer 102 and the light emitting layer 104 can contribute to providing a high quality light emitting layer 104 with low crystal defect density such as misfit dislocations and stacking faults. The boron-containing III-V group compound semiconductor composition gradient layer has an increasing layer thickness direction as seen in the conventional boron-containing III-V group compound semiconductor layer forming the buffer layer (see Japanese Patent Laid-Open No. 2000-22211 above). It can be configured in any manner that the boron composition ratio is increased or decreased uniformly, stepwise, or non-linearly. For example, a substrate 1 made of silicon
01 on the light emitting layer 10 made of gallium phosphide (GaP)
4 is provided, the boron composition ratio (= X) at the interface with the silicon substrate 101 is set to 0.02, and the boron composition ratio is linearly reduced to 0 (zero) at the interface with the GaP light emitting layer. ) Boron phosphide / gallium (B _α Ga _δ P: α = 0.02 → 0, which has a gradient in the composition ratio (= α), correspondingly, δ
= 0.98 → 1.00, α + δ = 1) The composition gradient layer can effectively act as a functional layer that relaxes the lattice mismatch between the substrate 101 or the buffer layer 102 and the light emitting layer 104.

In the fourth embodiment of the present invention, the barrier layer 103 having a composition gradient is provided on the buffer layer 102 from a boron-containing Group III-V compound semiconductor layer lattice-matched to the single crystal material forming the substrate 101. Is preferred. For example, substrate 1
01 is silicon (lattice constant≈5.431Å), and the buffer layer 102 is boron phosphide / gallium (B _0.02 Ga _0.98 P:
Lattice constant≈5.431Å), and the boron composition ratio (= X) is 0.
An example of the composition is a B _X Ga _{1 -X} P composition gradient layer having a content of 02 (= 2%). When the buffer layer 102 is made of a material that is lattice-matched to the single crystal material of the substrate 101, it is particularly effective in suppressing the generation of crystal defects such as misfit dislocations due to the lattice mismatch, and the crystallinity is improved. An excellent quality barrier layer 103 and thus a light emitting layer 104 can be provided.

The barrier layer 103 is composed of a composition gradient layer having a boron composition ratio that gives a larger bandgap than the light emitting layer 104. At least a region on the surface side facing the buffer layer 102 on the side opposite to the surface facing the light emitting layer 104 is composed of a boron-containing III-V compound semiconductor layer having a bandgap exceeding the light emitting layer 104. The barrier layer 103 having such a high forbidden band width can be preferably composed of a boron phosphide (BP) based semiconductor. For example, the growth rate, group III constituent elements and V
Supply ratio of raw materials of group constituent elements (so-called V / III ratio)
Can be constituted by using a monomeric boron phosphide (BP) having a bandgap at room temperature of 3.0 ± 0.2 eV, which is obtained by setting the above-mentioned value as a base material (the above-mentioned Japanese Patent Application No. Two
001-158282). For example, if a mixed crystal of gallium phosphide (GaP) is used as a base material of a monomer BP having a bandgap of 3.0 eV at room temperature, the bandgap of 2.
3.0e above 3eV (corresponding to the band gap of GaP)
A boron phosphide / gallium (B _X Ga _1-X P: 0 ≦ X ≦ 1) composition gradient layer having a V (corresponding to the band gap of BP) or less can be formed. By the way, even if boron phosphide (BP) having a conventional band gap of about 2.0 eV is mixed with GaP, 2.
B _X G with a small bandgap of more than 0 eV and less than 2.3 eV
It only results in a _1-X P. That is, for example, Ga
It is not possible to form a barrier layer that exerts a barrier action on the entire light emitting layer made of As _{1 -Z} P _Z (0 ≦ Z ≦ 1). The band gap is obtained from the wavelength (photon energy) dependence of the complex permittivity (ε ₂ = 2 · n · k) given by the product value of the refractive index (= n) and the extinction coefficient (= k), for example. To be

The light emitting layer 104 provided on the barrier layer 103 is
For example, it is composed of a gallium-containing III-V compound semiconductor layer containing gallium (Ga) and phosphorus (P). As an example, gallium arsenide phosphide (GaAs _1-Z P _Z : 0 ≦ Z ≦
Examples of forming the light emitting layer 104 from 1) are given. Ga
From P, a light emitting layer 104 that emits pure green (wavelength≈555 nm) to red band light can be formed. For example, zinc (Z
The GaP layer to which n) and oxygen (O) are added can be used as the light emitting layer 104 that emits red band light. Also, GaAs
_1-Z from P _Z mixed crystal, for example, may constitute the light emitting layer 104 to bring the emission of yellow band or orange band. Further, for example, an n-type GaAs _1-X P _X layer to which nitrogen (N) is added is nitrogen (N).
Isoelectronic traps of
rap) light-emitting layer 1 capable of producing high-intensity light emission by the action
It is useful as 04.

The light emitting layer 104 also includes the barrier layer 10 described above.
Boron-containing III-
It can also be composed of a group V compound semiconductor layer. On the surface of the composition gradient layer having a composition that lattice-matches the light emitting layer, a boron-containing group IIIV compound semiconductor layer forming the surface can be further laminated to a desired thickness to form the light emitting layer 104.
If a light emitting layer 104 made of the same material as the barrier layer 103 is laminated on the surface of the barrier layer 103, both layers 103,
Due to the matching of the lattice constants of 104, it is possible to obtain the light emitting layer 104 with a low crystal defect density due to the lattice mismatch. As a good example of the second embodiment of the present invention, both the barrier layer 103 and the light emitting layer 104 are made of conductive boron phosphide gallium (B _α Ga _δ P: 0 <α ≦ 1, 0 ≦ δ <1, α +
There is an example in which δ = 1). Further, both layers 103 and 104 are formed of a boron phosphide / indium mixed crystal (B _α I
An example including n _{1- α} P: 0 <α ≦ 1) is given.

The light emitting layer 104 is formed of boron arsenide phosphide.
Gallium (B _Y Ga _1-Y As _1-Z P _Z : 0 ≦ Y <1, 0 <Z
≦ 1). B _Y Ga _1-Y As _1-Z P _Z (0 ≦ Y
<1, 0 <Z ≦ 1, and the boron (B) composition ratio (=
If Y) is increased, a gallium-containing group III-V compound semiconductor having a forbidden band width of gallium arsenide phosphide (GaAs _1-Z P _Z : 0 ≦ Z ≦ 1) or more, which is a conventional constituent material of the light-emitting layer, can be obtained. Can be configured. Therefore, these are GaAs _1-Z P _Z (0 ≦ Z
It can be suitably used as the light emitting layer 104 that emits light having a wavelength shorter than ≦ 1). As a good example of the third embodiment of the present invention, the light emitting layer is made of silicon (lattice constant ≈5.431Å).
There is an example in which it is composed of B _0.02 Ga _0.98 P that lattice-matches with. _{B Y Ga 1-Y As 1} -Z P Z mixed crystals of boron phosphide is base material (BP) and phosphorus arsenic (BAs) are all indirect transition (indirect transition) type, group III-V compound semiconductor (See “Introduction to Semiconductor Devices” above, page 28). Therefore, the B _Y Ga _1-Y As _1-Z P _Z mixed crystal layer to which an element having a large electronegativity such as nitrogen (N) is added as an isoelectronic trap is predominantly used as the light-emitting layer 104 that provides high-intensity light emission Available.

In the fifth embodiment of the present invention, in particular, the substrate
101 is silicon, and the substrate 101 and the light emitting layer 104
The intermediate barrier layer 103 has the same conductivity as the silicon of the substrate 101.
Conductive n-type or p-type B_αGa_δP (0 <α ≦ 1, 0
≦ δ <1, α + δ = 1) layers. Also, the present invention
In the sixth embodiment of the present invention, in particular, the substrate 101 is made of silicon.
The barrier layer 103 is of the same conductivity type as the substrate silicon.
Shaped or p-shaped B_αIn _{1- α}Constructed from P (0 <α ≦ 1) layers
To achieve. B_αGa_δP (0 <α ≦ 1, 0 ≦ δ ≦ 1) and
B_αIn_{1- α}P (0 <α ≦ 1) depends on the boron composition ratio
As the substrate 101 (lattice constant ≈5.431)
Å) and B_YGa_1-YAs_1-ZP_ZLattice matched to both emitting layers
There is an advantage that the composition gradient layer can be easily constructed. p-type barrier
P-type dopant for obtaining layer 103
As zinc (Zn), magnesium (Mg) and beryl
Illustrative examples are Group II elements such as um (Be). Also,
Silicon (Si), tin (Sn), etc. as the n-type dopant
Group IV elements, as well as sulfur (S), selenium (Se) and tellurium
Examples thereof include Group VI elements such as Ru (Te).

The barrier layer 103 according to the present invention is used as the light emitting layer 1.
If the structure is provided on the upper part of 04, a double (DH) junction type light emitting part can be formed. Further, for example, it can be used as a barrier layer for forming a light emitting layer having a quantum well structure. In addition, a window (wi) that is provided in the LED in the direction of taking out the emitted light to the outside and that transmits the emitted light to the outside
It can be used as a layer.

In the seventh embodiment of the present invention, the laminated structure 1A is used as a base material to form a light emitting element. For example, L
The ED is configured by providing a front surface ohmic electrode 106 on the surface light emitting layer 104 forming the laminated structure 1A and disposing a back surface ohmic electrode 107 on the back surface of the substrate 101.
If the substrate 101 is made of a conductive single crystal material, an ohmic electrode can be provided on the back surface of the substrate 101, and the electrode forming process for manufacturing a light emitting element can be simplified. The p-type ohmic electrode can be made of, for example, a gold / zinc (Au / Zn) alloy, a gold / beryllium (Au / Be) alloy, or the like. In addition, gold / germanium (Au / Ge) alloy, gold /
Indium (Au / In) alloy, and gold / tin (Au / In)
An n-type ohmic electrode can be formed from a gold alloy such as Sn) alloy. The surface electrode 106 may be provided on the contact layer having good conductivity in order to form an electrode exhibiting good ohmic contact. The high bandgap boron-containing III-V compound semiconductor layer according to the present invention is a surface electrode 10 capable of transmitting emitted light in the extraction direction.
It is suitable for forming a contact layer for 6 purposes.

An integrated composite light emitting device can be obtained by additionally providing electronic components on the substrate 101 of the laminated structure 1A for controlling the operation of the light emitting device. Examples of electronic components for operation control include MES (Schottky metal junction type) and MOS.
Type (metal / oxide / semiconductor junction type) or pn junction type field effect transistor (FET), pn junction type surge diode, light receiving element and the like. For example, if an FET is attached, the light emitting element can be selectively turned on or off depending on, for example, a signal input to a gate electrode, and the light emitting element can be operated according to an electric signal. The emission intensity can be changed instantly. Further, by providing a surge diode, it is possible to avoid careless input of a large current to the light emitting element, and it is effective in stabilizing the light emitting element and extending the operating life. Further, if a light receiving element is attached, the intensity of light emitted from the light emitting element measured by the light receiving element is transmitted as an electric signal to, for example, the FET, and the light emission intensity of the light emitting element is modulated through the current amplification function of the FET. Composite element can be constructed. These electronic functional components can be attached, for example, to the surface of the substrate 101 made of silicon or the like.

The above-mentioned electronic component for controlling the operation of the light emitting device is as shown in the above-mentioned eighth embodiment of the present invention.
Directly provided on the surface of the substrate 101 such as silicon,
It can be provided on the boron-containing III-V group compound semiconductor layer forming the buffer layer 102 or the barrier layer 103 whose conductivity type can be easily controlled. An example of the ninth embodiment of the present invention will be described below. After once forming the laminated structure 1A, for example,
The light emitting layer 104 is removed only in a partial region of the laminated structure 1A by performing a plasma etching process, and the barrier layer 103 is removed.
Expose the surface of. Next, for example, a boron-containing III-V group compound semiconductor layer having a conductivity type opposite to that of the exposed layer 103 is bonded to the exposed surface of the barrier layer 103. By using the boron-containing III-V group compound semiconductor layer in this manner, a pn junction structure can be simply constructed, and therefore, for example, a pn junction Zener (Ze) which protects a light emitting element from destruction due to surge.
(nner) diode can be easily configured.

A high brightness lamp can be constructed from the light emitting device according to the present invention. For example, the lamp of the tenth embodiment of the present invention can be constructed by the following steps. As illustrated in FIG. 6, the boron-containing III according to the present invention on the substrate 11
The LED 10 provided with the group V compound semiconductor layer 12 is fixed to the central portion of the bowl body 16 plated with a metal such as silver (Ag) or aluminum (Al) on the pedestal 15 with a conductive bonding material. Thus, the unipolar electrode 14 provided on the bottom surface of the substrate 11 is electrically connected to the one terminal 17 attached to the pedestal 15. Further, the electrode 13 installed on the heterojunction structure light emitting portion 12 is connected to the other terminal 18 attached to the pedestal 15. A lamp can be constructed by encapsulating the bowl 16 with a general epoxy resin 19 for encapsulating a semiconductor. In addition, the laminated structure having the laminated structure according to the present invention can be easily cleaved, so that the laminated structure has a thickness of about 200 μm to about 300 μm.
A small-angle LED can also be formed, and thus a small-sized light-emitting diode lamp can be constructed which is particularly suitable as an indicator or the like having a small installation volume.

In the eleventh embodiment of the present invention, L
A light source is formed by assembling ED or resin-sealed diode lamps. For example, a constant voltage drive type light source can be configured by electrically connecting a plurality of LEDs in parallel.
Further, a constant current drive type light source can be configured by electrically connecting diode lamps in series. Unlike conventional incandescent lamp light sources, light sources using these LEDs do not radiate much heat when turned on, and thus can be particularly usefully used as cold light sources. For example, it can be used as a light source for displaying frozen foods. Further, for example, a light source suitably used for an outdoor display device, a traffic light for presenting a traffic signal, a direction indicator for an automobile, or a lighting device can be configured.

[0032]

Function: Single crystal substrate and boron arsenide phosphide / gallium (B _Y
Ga _1-Y As _1-Z P _Z : 0 ≦ Y <1, 0 <Z ≦ 1) The barrier layer made of a boron-containing III-V group compound semiconductor provided between the light-emitting layer and the light-emitting layer is a single substrate layer. It has an effect of relaxing the lattice mismatch between the crystalline material and the light emitting layer to provide a high quality light emitting layer having excellent crystallinity.

In particular, boron arsenide phosphide / gallium (B _Y G
a _1-Y As _1-Z P _Z : 0 ≦ Y <1, 0 <Z ≦ 1) The barrier layer made of a boron-containing group III-V compound semiconductor having the same lattice constant as that of the light emitting layer is particularly crystalline. It has an effect of providing a high quality light emitting layer excellent in

[0034]

Example 1 First Example A boron (phosphide) (BP) crystal layer and gallium phosphide (Ga) were formed on a silicon (Si) single crystal substrate.
P) The present invention will be described in detail with reference to a laminated structure having a single (SH) heterojunction structure with a single crystal layer and a case where a GaP-based LED is formed from the laminated structure.

A schematic plan view of the LED 2B according to this embodiment is shown in FIG. Moreover, LE along the broken line XX ′ of FIG.
The cross-sectional structure of D2B is shown in the schematic diagram of FIG. 2 and 3
In FIG. 1, the same components as those shown in FIG. 1 are designated by the same reference numerals.

Laminated structure 2A for light emitting device according to the present invention
The substrate 101 was made of boron (B) -doped p-type {100} -Si single crystal. The crystal plane that forms the surface of the substrate 101 is a {100} plane that is inclined by 2 degrees (°) in the [110] direction. Triethyl boron ((C ₂ H ₅ ) ₃ B) / phosphine (PH ₃ ) is formed on the surface of the substrate 101.
/ Hydrogen (H ₂ ) at 350 ° C. by atmospheric pressure MOCVD method
Then, in the as-grown state, a buffer layer 102 made of boron phosphide mainly composed of amorphous was deposited. The layer thickness of the buffer layer 102 was set to about 12 nm.

On the surface of the buffer layer 102, (C₂H_Five)₃
B / trimethylindium ((CH₃) ₃In) / PH₃
/ H₂System at atmospheric pressure by the MOCVD method
P-type B doped with um (Mg)_XIn_1-XP composition
The layered structure was laminated as the barrier layer 103. p type B_XIn_1-XP
The boron composition ratio (= X) of the composition gradient layer is equal to that of the buffer layer 102.
Straight line so that the joint interface is 1.00 and the surface is 0.32
Have been reduced. B used as the lower clad layer_XI
n_1-XIs the P composition gradient layer 103 mainly composed of {110} crystal faces?
It was composed of Magnesium (Mg)
The bis-cyclopentadienyl magnesi
Um (Molecular formula: bis- (C_FiveH_Four)₂Mg) was used.
P-type B forming the lower barrier layer 103_XIn_1-XP composition gradient layer
Carrier concentration is about 8 × 10¹⁸cm^-3And Layer thickness is about 1
000 nm. The buffer layer 102 was used as a base layer
Therefore, p-type B_XIn_1-XP (X = 1.00 → 0.32) obstacle
The wall layer 103 becomes a continuous film without cracks.
It was

A light emitting layer 104 made of n-type gallium phosphide (GaP) was laminated on the barrier layer 103 made of the p-type B _X In _{1 -X} P composition gradient layer. The light emitting layer 104 is a continuous film having no cracks because the surface is provided on the B _0.32 In _0.68 P barrier layer 103 having a composition that lattice-matches to GaP (lattice constant ≈ 5.450 Å). Silicon (Si) is used as the n-type dopant, and the carrier concentration is about 1 × 1.
It was set to 0 ¹⁷ cm ^-3 . The layer thickness of the light emitting layer 104 is about 180 nm.
And The light emitting layer 104 is formed by trimethylgallium ((C
According to the H ₃ ) ₃ Ga) / PH ₃ / H ₂ system atmospheric pressure MOCVD method, ammonia (N 2
Nitrogen (N) doped as isoelectronic traps using H _3). The nitrogen atom concentration inside the GaP light emitting layer 104 is determined by the secondary ion mass spectrometry (SIM
According to S), the amount was determined to be about 7 × 10 ¹⁸ atoms / cm ³ .

On the surface of the light emitting layer 104, a surface electrode 106 which also serves as a pedestal electrode for circular connection is arranged. The surface electrode 106 was composed of a gold (Au) / germanium (Ge) vacuum deposition film. The diameter of the surface electrode 106 is 120 μm
And Further, the back surface ohmic electrode 107 is arranged on substantially the entire back surface of the p-type Si substrate 101 to form the LED 1B. The p-type back electrode 107 is aluminum (Al)
It was composed of a vacuum deposited film. Next, a laminated structure 2A having a Si single crystal 101 having a {100} crystal plane as a main surface as a substrate
Is cleaved along the [110] crystal orientation, and one side is approximately 300
A square LED chip 2B having a size of μm was used.

When an operating current of 20 milliamperes (mA) was passed in the forward direction between the front and back electrodes 106 to 107, green light having an emission center wavelength of about 557 nm was emitted from the LED 2B. The brightness in a chip state measured using a general integrating sphere was about 6 millicandelas (mcd), and an SH junction green LED with high emission intensity was provided. The forward voltage (so-called Vf) obtained from the IV characteristic is about 2.2 V (forward current = 20 mA).
Became. The reverse voltage is about 8V (reverse current = 1
0 μA), and a high withstand voltage LED was provided.

(Second Embodiment) Gallium phosphide (GaP)
A {110} -boron phosphide / gallium (B _X Ga _1-X P: 0 ≦ X ≦ 1) crystal layer and a gallium boron phosphide (B _X Ga _1-X P) light emitting layer are formed on a single crystal substrate. Laminated structure having double (DH) heterojunction structure and its laminated structure to GaP
The present invention will be specifically described by taking a case of forming a system LED as an example.

A schematic sectional view of the LED 3B according to this embodiment is shown in FIG. 4, the same components as those shown in FIGS. 2 and 3 are designated by the same reference numerals.

Laminated structure 3A for light emitting device according to the present invention
Made a substrate 101 of silicon (Si) -doped n-type {100} -GaP single crystal. On the surface of the substrate 101, triethylboron ((C ₂ H ₅ ) ₃ B) / trimethylgallium ((CH ₃ ) ₃ Ga) / phosphine (PH ₃ ) / hydrogen (H ₂ ) based atmospheric pressure MOCVD method is used. A buffer layer 102 made of polycrystalline boron phosphide (BP) was deposited at 580 ° C. The layer thickness of the buffer layer 102 was set to about 30 nm.

On the surface of the buffer layer 102, (C ₂ H ₅ ) ₃
An n-type B _X Ga _{1 -X} P composition gradient layer was deposited as the barrier layer 103 at 800 ° C. by the B / (CH ₃ ) ₃ Ga / PH ₃ / H ₂ system atmospheric pressure MOCVD method. p-type B _X Ga _1-X P barrier layer 103
As for the boron composition (= X), the boron (B) composition ratio was set to 1.00 at the bonding interface with the buffer layer 102, and the boron composition ratio was linearly decreased to 0.05 on the surface. The B _X Ga _1-X P composition gradient layer used as the lower clad layer is B _X Ga _1-X P (X = 1.00 → 0.0) stacked in parallel with the surface of the Si substrate.
It was composed of the {110} crystal plane of 5).
The {110} B _X Ga _1-X P barrier layer 103 has a growth rate of 30 nm / min and a V / III ratio (= PH ₃ /
Since the (CH ₃ ) ₃ B supply ratio) was set to 50, the forbidden band width at room temperature obtained from the photon energy dependence of the complex dielectric constant was about 3.0 eV. A hydrogen-disilane (Si ₂ H ₆ ) mixed gas was used as a doping source of silicon (Si). The carrier concentration of the n-type B _X Ga _1-X P barrier layer 103 forming the lower clad layer was set to about 8 × 10 ¹⁸ cm ^-3 . The layer thickness was about 1000 nm. The n-type B _X Ga _{1 -X} P barrier layer 103 was a continuous film without cracks due to the effect of the buffer layer 102 as the underlayer.

N type B_XGa_1-XOn the P barrier layer 103, n
Boron phosphide / gallium (B_0.05Ga _0.95Consists of P)
The light emitting layer 104 was laminated. Silicon as n-type dopant
Using silicon (Si), the carrier concentration is about 1 × 10¹⁷cm^-3
And The layer thickness of the light emitting layer 104 was about 150 nm. Departure
Light layer 104 (C₂H_Five)₃B / (CH₃)₃Ga / PH₃/
H₂ Grow at 800 ° C according to the atmospheric pressure MOCVD method
At the time of ammonia (NH₃) To use nitrogen (N)
Doped as an isoelectronic trap
It was B_0.05Ga_0.95Nitrogen atom concentration inside the P emission layer 104
Is about 8 × by secondary ion mass spectrometry (SIMS)
10¹⁸Atom / cm³Was quantified.

N type B_0.05Ga_0.95Surface of P light emitting layer 104
Above, (C₂H_Five)₃B / PH₃/ H₂System atmospheric pressure MOCVD
P-type phosphide mainly composed of amorphous material at 350 ° C.
The elemental (BP) layer was bonded as the barrier layer 105. p-type
The above-mentioned biscyclopentadienylmer is used as the dopant.
Gnesium was used. Carrier concentration is about 2 x 10¹⁹cm
^-3And the layer thickness was 680 nm. Wavelength (= λ) and its
Absorption coefficient calculated from extinction coefficient (= k) at wavelength
(= 4 ・ π ・ k / λ: cm^-1) Obtained barrier layer
Room temperature prohibition of BP layer mainly composed of amorphous material constituting 105
The band width was about 3.1 eV. n type B_XGa_1-XP lower obstacle
Wall layer 103 and n-type B_0.05Ga_0.95P light emitting layer 104 and
And p-type BP layer as the upper barrier layer 105
A light emitting portion having a ruhetero (DH) structure was formed.

At the center of the surface of the upper barrier layer 105 composed mainly of amorphous boron phosphide, a p-type surface electrode 106 also serving as a circular connection base electrode was arranged. The p-type surface electrode 106 was composed of a gold (Au) / zinc (Zn) vacuum deposited film. The diameter of the surface electrode 106 was 130 μm. In addition, on the substantially entire back surface of the n-type GaP substrate 101,
The LED 3B was constructed by arranging the n-type back electrode 107.
The n-type back electrode 107 is made of gold (Au) / germanium (G).
e) It was composed of a vacuum deposited film. Next, a laminated structure 3A having a {100} crystal plane as a main surface but having a GaP single crystal 101 as a substrate is cleaved along the [110] crystal orientation to form a square LED chip 3B having a side of about 250 μm. did.

When an operating current of 20 milliamperes (mA) was passed in the forward direction between the front and back electrodes 106 to 107, the emission center wavelength was about 540 nm from the LED 3B.
And emitted green light. The brightness in a chip state measured by using a general integrating sphere is about 5 millicandelas (mcd), and a short wavelength visible light L with high emission intensity is obtained.
ED provided. The forward voltage (so-called Vf) obtained from the IV characteristic is about 2.3 V (forward current = 20 mA).
Became. The reverse voltage is about 8V (reverse current = 1
0 μA), and a high withstand voltage LED was provided.

(Third Embodiment) A case where a GaAsP-based LED is formed from a laminated structure provided with a buffer layer that is structurally matched to a Si single crystal on a silicon (Si) single crystal substrate will be described as an example. The present invention will be specifically described below.

A schematic sectional view of the LED 4B according to this embodiment is shown in FIG. 5, the same components as those shown in FIGS. 2 to 4 are designated by the same reference numerals.

Laminated structure for light emitting device 4A according to the present invention
Was configured with an antimony (Sb) -doped n-type {100} -Si single crystal as the substrate 101. On the surface of the substrate 101, triethylboron ((C ₂ H ₅ ) ₃ B) / trimethylindium ((CH ₃ ) ₃ In) / phosphine (PH ₃ ) is formed.
/ Hydrogen (H ₂ ) -based low pressure MOCVD method was used to form a buffer layer 102 of boron phosphide / indium (B _X In _1-X P) at 400 ° C. The composition ratio of boron (B) (= X) is S
It was set to 0.32, which yields the same lattice constant (≈5.431Å) as the i single crystal. The pressure during film formation was about 5 × 10 ⁴ Pascal (pressure unit: Pa). The layer thickness of the buffer layer 102 was set to about 10 nm.

On the surface of the buffer layer 102, (C ₂ H ₅ ) ₃
A Si-doped B _X In _1-X P composition gradient layer was deposited as the barrier layer 103 at 800 ° C. by the B / (CH ₃ ) ₃ In / PH ₃ / H ₂ system low pressure MOCVD method. Regarding the boron composition ratio (= X) of the n-type B _X In _1-X P composition gradient layer 102, the boron (B) composition ratio at the junction interface with the buffer layer 103 is 0.32, and the boron composition ratio at the surface is 0. .24 linearly. B _X Ga _1-X P (X = 0.32 → 0.
24) The composition gradient layer is mainly composed of B _X In _{1 -X} P crystal {11
0} crystal plane. Also, {11
0} -B _X In _1-X P composition gradient layer has a growth rate of 20 per minute.
and the V / III ratio (= PH ₃ / (CH ₃ ) ₃ B supply ratio) is 40, the forbidden band width at room temperature obtained from the photon energy dependence of the complex permittivity is about 2.
It became 8 eV. A hydrogen-disilane (Si ₂ H ₆ ) mixed gas was used as a doping source of silicon (Si). The carrier concentration of the n-type B _X In _1-X P barrier layer 103 forming the lower cladding layer was set to about 2 × 10 ¹⁸ cm ^-3 . Layer thickness is about 500n
m. Depending on the effect of the base layer, the buffer layer 102 is
The n-type B _X In _1-X P barrier layer 103 was a continuous film without cracks.

On the n-type B _X In _1-X P barrier layer 103, n
A light emitting layer 104 made of gallium arsenide phosphide (GaAs _0.50 P _0.50 ) was laminated. Silicon (Si) is used as an n-type dopant, and the carrier concentration is about 2 × 10 ¹⁷ cm ^−3.
And The layer thickness of the light emitting layer 104 was about 450 nm. The light emitting layer 104 is formed of (CH ₃ ) ₃ Ga / arsine (AsH ₃ ) /
According to the PH ₃ / H ₂ -based low pressure MOCVD method, when growing at 800 ° C., nitrogen (N) was doped as an isoelectronic trap using ammonia (NH ₃ ). The nitrogen atom concentration inside the GaAs _0.50 P _0.50 light emitting layer 104 was quantified by secondary ion mass spectrometry (SIMS) to be about 5 × 10 ¹⁸ atoms / cm ³ .

N-type GaAs_0.50P_0.50Surface of light emitting layer 104
On the surface, (C₂H_Five)₃B / PH₃/ H ₂ System reduction MOCVD
P-type phosphide mainly composed of amorphous material at 350 ° C.
The elemental (BP) layer was bonded as the upper barrier layer 105. p
The above-mentioned biscyclopentadiene is used as
Lumagnesium was used. Carrier concentration is about 2 x 10¹⁹
cm^-3And the layer thickness was 1080 nm. Wavelength (= λ)
And the extinction coefficient (= k) at that wavelength
Collection coefficient (= 4 ・ π ・ k / λ: cm^-1) Was used
Amorphous BP layer mainly constituting the upper barrier layer 105
The room temperature bandgap of was about 3.1 eV. n type B_XIn
_1-XP lower barrier layer 103 and n-type GaAs_{0. 50}P_0.50Departure
The optical layer 104 and the p-type BP layer as the upper barrier layer 105
Forming a light emitting part of a pn junction type double hetero (DH) structure
It was

At the central portion of the surface of the upper barrier layer 105 mainly composed of amorphous boron phosphide, a p-type surface electrode 106 also serving as a circular connection base electrode was arranged. The p-type surface electrode 106 was composed of a gold (Au) / zinc (Zn) vacuum deposited film. The diameter of the surface electrode 106 was 130 μm. In addition, on the substantially entire back surface of the n-type Si substrate 101, n
The shaped back electrode 107 is arranged to form the LED 4B. n
The shaped back electrode 107 was composed of a gold (Au) vacuum deposition film. Next, a laminated structure 4A having a {100} crystal plane as a main surface but a Si single crystal 101 as a substrate is cleaved along the [110] crystal orientation to form a square LED chip 4B having a side of about 250 μm. did.

When a forward operating current of 20 milliamperes (mA) was passed between the front and back electrodes 106 to 107, the emission center wavelength was about 600 nm from the LED 4B.
And emitted green light. The luminance in a chip state measured by using a general integrating sphere is about 7 millicandelas (mcd), and a short wavelength visible L with high emission intensity is obtained.
ED provided. The forward voltage (so-called Vf) obtained from the IV characteristic is about 2.3 V (forward current = 20 mA).
Became. The reverse voltage is about 5V (reverse current = 1
0 μA), and a high withstand voltage LED was provided.

[0057]

INDUSTRIAL APPLICABILITY In a laminated structure for a light emitting device, which is provided on a single crystal substrate and has a gallium-containing III-V group compound semiconductor layer as a light emitting layer, the light emitting layer is provided with a gradient in boron composition. With the structure provided on the boron-containing III-V group compound semiconductor composition gradient layer, the lattice mismatch between the single crystal material forming the substrate and the light emitting layer is relaxed, so that light emission with good crystallinity is achieved. A laminated structure for a light emitting device including layers can be formed. Further, in combination with the action of the boron-containing III-V group compound semiconductor composition gradient layer as a barrier layer exerting a barrier action to the light emitting layer, the laminated structure for a light emitting device according to the present invention provides high intensity light emission. A light emitting device, a lamp and a light source can be provided.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a laminated structure for a light emitting device showing an embodiment of the present invention.

FIG. 2 is a schematic plan view of the LED described in the first embodiment.

FIG. 3 is a schematic cross-sectional view of the LED shown in FIG. 2 taken along the broken line XX ′.

FIG. 4 is a schematic sectional view of an LED described in a second embodiment.

FIG. 5 is a schematic sectional view of an LED described in a third embodiment.

FIG. 6 is a schematic view illustrating the cross-sectional structure of the lamp according to the present invention.

[Explanation of symbols]

1A, 2A, 3A, 4A Light emitting element laminated structure 2B, 3B, 4B Light emitting element (LED) 11 board 12 Heterojunction light emitting part 13 Front side electrode 14 Substrate backside electrode 15 pedestal 16 bowl 17, 18 terminals 19 Sealing resin 101 single crystal substrate 102 buffer layer 103 barrier layer 104 light emitting layer 105 upper barrier layer 106 surface electrode 107 Back electrode

Claims (11)

[Claims] 1. A single crystal substrate, a buffer layer laminated on the substrate, and boron containing boron (B) laminated on the buffer layer.
Group V compound semiconductor (boron-containing III-V group compound semiconductor)
And a gallium (G) layer.
III-V group compound semiconductor containing a) (gallium-containing II
A laminated structure for a light emitting device, comprising a light emitting layer made of a group IV compound semiconductor), the barrier layer having a boron composition ratio lattice-matched to the buffer layer on a surface facing the buffer layer. And a composition gradient layer made of a boron-containing group III-V compound semiconductor having a boron composition ratio lattice-matched to the light emitting layer on the surface facing the light emitting layer and having a boron composition ratio gradient in the increasing direction of the layer thickness. A laminated structure for a light emitting device, which is characterized by comprising: 2. A light emitting layer made of a gallium-containing III-V group compound semiconductor is made of the same material as a boron-containing III-V group compound semiconductor forming a surface of a barrier layer facing the light emitting layer. The laminated structure for a light emitting device according to claim 1. 3. The light emitting layer is formed of boron arsenide phosphide / gallium (B).
_Y Ga _1-Y As _1-Z P _Z : 0 ≦ Y <1, 0 <Z ≦ 1), The laminated structure for a light-emitting element according to claim 1 or 2, characterized in that: 4. A barrier layer made of a boron-containing III-V group compound semiconductor is provided on a buffer layer made of a boron-containing III-V group compound semiconductor having a composition lattice-matched to a single crystal material constituting a substrate. The laminated structure for a light emitting device according to claim 1, wherein the laminated structure is a light emitting device. 5. A silicon single crystal (silicon) is used as a single crystal substrate, and a barrier layer made of a boron-containing III-V group compound semiconductor layer is formed of boron phosphide / gallium (B _X Ga _1-X P: 0 <X ≦
The laminated structure for a light-emitting device according to claim 1, wherein the laminated structure for a light-emitting device is configured from 1). 6. A single crystal substrate is made of silicon single crystal (silicon), and a barrier layer composed of a boron-containing III-V group compound semiconductor layer is formed of boron phosphide / indium (B _X In _1-X P: 0 <X ≦
The laminated structure for a light-emitting device according to claim 1, wherein the laminated structure for a light-emitting device is configured from 1). 7. A light emitting device comprising the laminated structure for a light emitting device according to any one of claims 1 to 6. 8. A light emitting device according to claim 7, wherein the same single crystal substrate is provided with a light emitting device and an electronic component for controlling the intensity of light emitted from the light emitting device. 9. The light emitting device according to claim 8, wherein the electronic component is provided on a barrier layer made of a boron-containing III-V group compound semiconductor. 10. A lamp comprising the light emitting device according to claim 7. 11. A light source comprising the lamp according to claim 10.