JP2006108518A - Semiconductor light-emitting element, and epitaxial wafer therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting element that can obtain an LED and an LD and has a structure that is high in luminance, high in reliability and reduced in time deterioration caused by a reverse breakdown voltage by suppressing the dispersion of zinc into an active layer, even if zinc is used as a dopant in a p-type semiconductor layer in the vicinity of the active payer. <P>SOLUTION: The semiconductor light-emitting element forms a light-emitting part obtained by inserting the active layer between n-type and p-type clad layers on an n-type substrate. Between p-type semiconductor layers (an Mg-doped p-type current diffusion layer 8, an Mg-doped p-type contact layer 9, an Mg-doped p-type clad layer 11) which are doped with magnesium at least and the active layer, a p-type semiconductor layer (a Zn-doped p-type clad layer 5) at least doped with zinc is installed. Zinc is diffused to a side distant from the active layer 4 by the mutual diffusion of magnesium and zinc. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a structure of a semiconductor light emitting device (light emitting diode LED, semiconductor laser LD) having a high brightness and a long life and an epitaxial wafer for a semiconductor light emitting device, and in particular, zinc (Zn) and magnesium (Mg) are used as p-type impurities. The present invention relates to a structure suitable for the AlGaInP light emitting element.

  Light emitting diodes (LEDs) are widely used as industrial and consumer display elements. As a high-brightness LED, there was an AlGaAs red LED. However, although LEDs with shorter wavelengths than red were GaAsP and GaP, only low luminance was obtained. However, since it has recently become possible to grow AlGaInP-based crystal layers by the MOVPE method, it has become possible to produce orange, yellow, and green high-intensity LEDs.

  Conventionally, it is known that when a LED or LD operates at a high output or at a high temperature, a leakage current due to an overflow of electrons from the active layer to the p-type cladding layer increases, and a threshold current and an operating current increase. In order to achieve stable high temperature and high output operation, it is desirable to increase the carrier concentration of the p-type cladding layer as much as possible. Therefore, zinc (Zn) is generally used as the p-type impurity of the p-type cladding layer.

However, when Zn is used as the p-type impurity, there is a problem that Zn is diffused to the active layer as the carrier concentration of the p-type cladding layer is increased, leading to deterioration of device characteristics and reliability. For this reason, Zn had to be doped at a low concentration. The carrier concentration of the p-type cladding layer when Zn is used as the p-type impurity is normally set to a relatively low concentration of about 4 × 10 ¹⁷ cm ⁻³ .

  As a countermeasure against this problem, a light emitting part in which an active layer is sandwiched between an n-type and a p-type cladding layer is formed on an n-type substrate, and a Zn-doped p-type current spreading layer is formed on the Zn-doped p-type cladding layer. In the structure of the semiconductor light emitting device, it has been proposed to insert a Zn diffusion suppression layer (undoped AlGaInP spacer layer) of 500 nm or more between the undoped active layer and the p-type cladding layer (see, for example, Patent Document 1). This Patent Document 1 is a layer structure of a semiconductor light emitting device in which a Zn-doped p-type cladding layer and a Zn-doped p-type current distribution layer are sequentially laminated on an active layer, and it is assumed that Zn is directed to the active layer side. ing.

  It is also known to increase the carrier concentration of the p-type cladding layer and the p-type contact layer thereon using magnesium (Mg) having a smaller diffusion constant than Zn as the p-type impurity (for example, patents) Reference 2). In Patent Document 2, a layered structure of a semiconductor light emitting device is formed in which an Mg-doped p-type cladding layer and an Mg-doped p-type contact are sequentially laminated on an active layer.

In addition, a Zn-doped p-type cladding layer and a Zn-doped p-type current diffusion layer are sequentially stacked on the active layer, and a thin high-resistance layer doped with Mg is provided in the Zn-doped p-type current diffusion layer. The structure is known (see, for example, Patent Document 3). This Mg-doped p-type high resistance layer is inserted for the purpose of diffusing the current injected from the p-side electrode in the cross-sectional lateral direction. In this Patent Document 3, a layer structure of a semiconductor light emitting device in which a Zn-doped p-type cladding layer, an Mg-doped p-type high-resistance layer, and a Zn-doped p-type cladding layer are sequentially laminated on an active layer.
JP 2003-179254 A Japanese Patent No. 2778405 JP-A-8-3211

  As described above, in a semiconductor light emitting device having a structure in which an active layer is sandwiched between an n-type and a p-type cladding layer on an n-type substrate, Zn has conventionally been used as a p-type dopant for the p-type cladding layer. Although it has been used, since Zn has a feature of being easily diffused, when Zn is doped into the p-type cladding layer, this Zn diffuses to the active layer, resulting in a decrease in emission luminance and reliability. There has been a problem that it causes a decrease and a reverse breakdown with time.

  On the other hand, as a p-type dopant instead of Zn, Mg can be added to the p-type cladding layer because it is less diffusible than Zn. For example, a GaP layer is used for the current diffusion layer. In the case of an AlGaInP-based LED epitaxial structure, there is an energy barrier between the p-type AlGaInP cladding layer and the p-type GaP current diffusion layer due to the band discontinuity, and there is a property that current does not easily flow. Therefore, a p-type AlGaInP semiconductor layer (band discontinuity eliminating layer) with a high carrier concentration is inserted to reduce this energy barrier. However, since the desired carrier concentration cannot be obtained with Mg dopant, there is a problem that this energy barrier cannot be relaxed and the Vf becomes high.

  In short, conventionally, when Zn is used as the p-type dopant of the p-type cladding layer, there is a problem that Zn diffuses to the active layer, and when Mg is used, a desired carrier concentration is difficult to obtain.

  Therefore, the object of the present invention is to solve the above problems, and even if Zn is used as a dopant in the p-type semiconductor layer in the vicinity of the active layer, Zn diffusion into the active layer is reduced, resulting in high brightness, high reliability, Another object of the present invention is to provide a light-emitting element capable of obtaining an LED and an LD having a reverse breakdown voltage structure with little deterioration with time.

  In order to achieve the above object, the present invention is configured as follows.

  The semiconductor light-emitting device according to the invention of claim 1 is a semiconductor light-emitting device having a structure in which a light-emitting portion is formed by sandwiching an active layer between a first conductive type and a second conductive type cladding layer on a first conductive type substrate. A p-type semiconductor layer doped with at least zinc (Zn) is disposed between the p-type semiconductor layer doped with at least magnesium (Mg) and the active layer, and zinc is diffused from the active layer by mutual diffusion of magnesium and zinc. It is characterized by a structure that diffuses to the far side.

  The present invention includes a structure (FIGS. 1 and 2) in which a Zn-doped p-type cladding layer is disposed between an Mg-doped p-type current diffusion layer and an active layer, and an Mg-doped p-type cladding layer and an active layer. 3 includes a structure in which a Zn-doped p-type cladding layer is provided (FIG. 3), and a structure in which a Zn-doped p-type cladding layer is provided between the Mg-doped p-type contact layer and the active layer. Here, the semiconductor light emitting device includes a light emitting diode and a laser diode.

  According to a second aspect of the present invention, there is provided a semiconductor light-emitting device comprising: a light-emitting portion in which an active layer is sandwiched between a first conductive type and a second conductive type cladding layer on a first conductive type substrate; In a semiconductor light emitting device having a structure in which a type current spreading layer is formed, a p-type semiconductor layer doped with at least zinc is disposed between a p-type semiconductor layer doped with at least magnesium and an active layer, and magnesium and zinc The structure is characterized in that zinc is diffused to the side farther from the active layer by interdiffusion. This specifies the structure (FIGS. 1 and 2) having the second conductivity type current spreading layer on the light emitting portion, and is different from claim 1 only in that respect.

  According to a third aspect of the present invention, in the semiconductor light emitting device according to the first or second aspect, the p-type semiconductor layer doped with at least magnesium and the p-type semiconductor layer doped with at least zinc are adjacent to each other. .

  According to a fourth aspect of the present invention, in the semiconductor light emitting device according to any one of the first to third aspects, of the first conductive type and the second conductive type clad layer constituting the light emitting portion, the side closer to the active layer. The p-type cladding layer is characterized in that at least zinc is doped.

  According to a fifth aspect of the present invention, in the semiconductor light emitting device according to any one of the first to fourth aspects, the first conductivity type substrate is GaAs and the light emitting portion is formed of AlGaInP or GaInP.

  An epitaxial wafer for a semiconductor light emitting device according to a sixth aspect of the present invention is a semiconductor light emitting device having a structure in which a light emitting portion is formed by sandwiching an active layer between a first conductive type and a second conductive type cladding layer on a first conductive type substrate. In an epitaxial wafer for devices, a p-type semiconductor layer doped with at least zinc is placed between a p-type semiconductor layer doped with at least magnesium and an active layer, and Zn is diffused from the active layer by mutual diffusion of magnesium and zinc. It is characterized by a structure that diffuses to the far side.

  The present invention includes a structure (FIGS. 1 and 2) in which a Zn-doped p-type cladding layer is disposed between an Mg-doped p-type current diffusion layer and an active layer, and an Mg-doped p-type cladding layer and an active layer. 3 includes a structure in which a Zn-doped p-type cladding layer is provided (FIG. 3), and a structure in which a Zn-doped p-type cladding layer is provided between the Mg-doped p-type contact layer and the active layer. Here, the epitaxial wafer for a semiconductor light emitting device includes the forms of an epitaxial wafer for a light emitting diode and an epitaxial wafer for a laser diode.

  According to a seventh aspect of the present invention, a light emitting portion is formed by sandwiching an active layer between a first conductive type and a second conductive type cladding layer on a first conductive type substrate, and a second conductive type current spreading layer is formed thereon. In the epitaxial wafer for a semiconductor light emitting device having the formed structure, a p-type semiconductor layer doped with at least zinc is disposed between the p-type semiconductor layer doped with at least magnesium and the active layer, and mutual diffusion of magnesium and zinc is performed. The structure is characterized in that zinc is diffused to the side farther from the active layer. This specifies the structure (FIGS. 1 and 2) having the second conductivity type current spreading layer on the light emitting portion, and is different from claim 6 only in that respect.

  The invention according to claim 8 is the epitaxial wafer for semiconductor light emitting device according to claim 6 or 7, wherein the p-type semiconductor layer doped with at least magnesium and the p-type semiconductor layer doped with at least zinc are adjacent to each other. Features.

  The invention of claim 9 is the epitaxial wafer for a semiconductor light emitting device according to any one of claims 6 to 8, wherein the active layer of the first conductivity type and the second conductivity type clad layer constituting the light emitting portion is used. The p-type cladding layer on the near side is doped with at least zinc.

  A tenth aspect of the present invention is the epitaxial wafer for a semiconductor light emitting device according to any one of the sixth to ninth aspects, wherein the first conductivity type substrate is GaAs and the light emitting portion is formed of AlGaInP or GaInP. And

<Key points of the invention>
In order to achieve the above object, according to the present invention, a p-type semiconductor layer (for example, a p-type cladding layer) near the active layer is doped with zinc and magnesium is doped adjacent to the semiconductor layer ( For example, a p-type current diffusion layer, a p-type contact layer, a p-type cladding layer, etc.) are provided. By doing so, zinc diffuses in the p-type semiconductor layer doped with magnesium, and as a result, zinc diffusion occurs in a direction away from the active layer. As a result, a light emitting device capable of obtaining an LED and an LD having a structure in which zinc is less diffused into the active layer can be manufactured. Thus, a semiconductor light emitting device with high luminance, high reliability, and low withstand voltage deterioration over time can be obtained. .

  The present invention differs from Patent Documents 1 to 3 in the following points.

  Patent Document 1 discloses a configuration in which only an undoped spacer layer, a Zn-doped p-type cladding layer, and a Zn-doped p-type current spreading layer exist on the active layer, that is, a configuration in which no Mg-doped layer exists on the active layer. Therefore, the idea of utilizing the interdiffusion of the present invention does not exist.

  Patent Document 2 has a configuration in which only an Mg-doped p-type cladding layer and an Mg-doped p-type contact layer exist on the active layer, that is, a configuration in which no Zn-doped layer exists on the active layer. The idea of utilizing the interdiffusion of the present invention does not exist.

  Patent Document 3 discloses a configuration in which a Zn-doped p-type cladding layer, a Zn-doped p-type current spreading layer, a Mg-doped p-type high resistance layer, and a Zn-doped p-type current spreading layer are present on the active layer. . However, this Mg-doped p-type high resistance layer is inserted for the purpose of diffusing the current injected from the p-side electrode in the lateral direction of the cross section. That is, Patent Document 3 belongs to a completely different technique that does not have the technical idea of the present invention that diffuses Zn to the side farther from the active layer by interdiffusion.

  According to the present invention, the following excellent effects can be obtained.

  According to the semiconductor light emitting device or the epitaxial wafer for a semiconductor light emitting device of the present invention, a p-type semiconductor layer doped with at least Zn is disposed between the p-type semiconductor layer doped with at least Mg and the active layer, and magnesium Since zinc is diffused to the side farther from the active layer by interdiffusion of zinc and zinc, zinc does not diffuse into the active layer compared to conventional light emitting diodes or laser diodes doped with zinc. Therefore, according to the present invention, it is possible to manufacture an LED or LD that does not have a decrease in light emission luminance, a decrease in reliability, and a reverse breakdown voltage with time.

  In addition, according to the semiconductor light emitting device or the epitaxial wafer for semiconductor light emitting device of the present invention, zinc is not diffused from the p-type semiconductor layer doped with Zn into the active layer due to its structure. Since the semiconductor layer (for example, the undoped spacer layer of Patent Document 1) for preventing Zn diffusion inserted between the layer and the p-type cladding layer can be eliminated, the manufacturing cost can be reduced.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

  1 is an n-type (first conductivity type) substrate 2 made of GaAs, an n-type cladding layer 3, an active layer 4, and a Zn-doped p-type (second conductivity type). The cladding layer 5, the Zn-doped p-type band discontinuity eliminating layer 6, the Zn-doped p-type current diffusion layer 7, the Mg-doped p-type current diffusion layer 8, and the Mg-doped p-type contact layer 9 are sequentially laminated. In this epitaxial wafer for semiconductor light emitting device, the back electrode 1 is formed on the entire back surface of the n-type substrate 2 side, and the surface electrode 10 is formed on a part of the Mg-doped p-type contact layer 9. The semiconductor light emitting device shown in FIG. 1 is manufactured by being divided into chips.

  An epitaxial wafer for producing the semiconductor light emitting device shown in FIG. 2 is formed on an n-type (first conductivity type) substrate 2 made of GaAs, an n-type cladding layer 3, an active layer 4, and a Zn-doped p-type (second conductivity type). The cladding layer 5, the Mg-doped p-type current diffusion layer 8, and the Mg-doped p-type contact layer 9 are sequentially laminated. In this epitaxial wafer for semiconductor light emitting device, the back electrode 1 is formed on the entire back surface of the n-type substrate 2 side, and the surface electrode 10 is formed on a part of the Mg-doped p-type contact layer 9. The semiconductor light emitting device shown in FIG. 2 is manufactured by being divided into chips.

  An epitaxial wafer for producing the semiconductor light emitting device shown in FIG. 3 is formed on an n-type (first conductivity type) substrate 2 made of GaAs, an n-type cladding layer 3, an active layer 4, and a Zn-doped p-type (second conductivity type). The cladding layer 5, the Mg-doped p-type cladding layer 11, and the Mg-doped p-type contact layer 9 are sequentially stacked. In this epitaxial wafer for semiconductor light emitting device, the back electrode 1 is formed on the entire back surface of the n-type substrate 2 side, and the surface electrode 10 is formed on a part of the Mg-doped p-type contact layer 9. The semiconductor light emitting device shown in FIG. 2 is manufactured by being divided into chips.

  In the semiconductor light emitting device of FIGS. 1 to 2, a light emitting part in which an active layer 4 is sandwiched between an n type cladding layer 3 and a p type cladding layer 5 is formed on an n type substrate 2, and an Mg doped p type current is formed thereon. In the structure in which the diffusion layer 8 and the Mg-doped p-type contact layer 9 are formed, a Zn-doped p-type cladding layer 5 is provided between the Mg-doped p-type current diffusion layer 8 and the active layer 4.

  In the semiconductor light emitting device of FIG. 3, a light emitting part is formed on an n type substrate 2 with an active layer 4 sandwiched between an n type clad layer 3 and a p type clad layer 5, and an Mg doped p type clad layer 11 is formed thereon. In the structure in which the Mg-doped p-type contact layer 9 is formed, a Zn-doped p-type cladding layer 5 is provided between the Mg-doped p-type cladding layer 11 and the active layer 4.

  In any of the semiconductor light emitting devices of FIGS. 1 to 3, a Zn-doped layer (Zn-doped p-type cladding layer 5, Zn-doped p-type band discontinuity eliminating layer 6, Zn-doped p-type) is formed above the active layer 4. A current diffusion layer 7) and an Mg doped layer (Mg doped p-type current diffusion layer 8, Mg doped p-type contact layer 9, Mg-doped p-type cladding layer 11) are sequentially provided. However, in the form of FIG. 1, the Zn-doped p-type cladding layer 5 and the p-type semiconductor layer (Mg-doped p-type current diffusion layer 8) are sandwiched between the Zn-doped p-type band discontinuity eliminating layer 6 and the Zn-doped p-type. 2 and 3, the Zn-doped p-type cladding layer 5 and the p-type semiconductor layer (Mg-doped p-type current diffusion layer 8, Mg-doped p-type cladding layer) are provided. 11) are provided adjacent to each other.

  Because of this structure, between the Zn-doped p-type cladding layer 5 and the like and the Mg-doped p-type semiconductor layer (Mg-doped p-type current diffusion layer 8, Mg-doped p-type contact layer 9 or Mg-doped p-type cladding layer 11), Interdiffusion between Zn and Mg occurs, and Zn such as the Zn-doped p-type cladding layer 5 is diffused farther from the active layer 4. Therefore, diffusion of Zn into the active layer 4 is suppressed.

  The structure of a light emitting diode (LED) according to an embodiment of the present invention is shown in FIG. In the following description, each layer is described as having a specific conductivity type, but the present invention is not limited to this, and the n-type and p-type semiconductor layers may be reversed.

On the n-type substrate 2 made of GaAs by the MOVPE method, the n-type cladding layer 3 made of Si-doped AlGaInP having a thickness of 0.5 μm and a carrier concentration of 1 × 10 ¹⁸ cm ⁻³ has a thickness of 0.5 μm. An active layer 4 made of undoped AlGaInP, a Zn-doped p-type cladding layer 5 made of Zn-doped AlGaInP with a thickness of 0.5 μm and a carrier concentration of 5 × 10 ¹⁷ cm ⁻³ , a thickness of 0.1 μm and a carrier concentration of 2 Zn doped p-type band discontinuity eliminating layer 6 made of Zn doped AlGaInP with × 10 ¹⁸ cm ⁻³ , Zn doped p type made of Zn doped GaP with a thickness of 0.5 μm and a carrier concentration of 1 × 10 ¹⁸ cm ⁻³ Current diffusion layer 7, Mg-doped p-type current diffusion layer 8 made of Mg-doped GaP with a thickness of 8 μm and a carrier concentration of 3 × 10 ¹⁸ cm ⁻³ , a thickness of 0.2 μm and a carrier concentration of 1 × 10 ¹⁹ cm ^- Mg-doped p-type contact layers 9 made of ³ Mg-doped GaP were sequentially formed.

  SIMS analysis (secondary ion analysis) confirmed that the p-type semiconductor layer contained both Zn and Mg, but the active layer did not diffuse and was an undoped layer.

  Then, after forming the back electrode 1 on the entire surface of the epitaxial wafer for semiconductor light emitting elements on the n-type substrate 2 side and the surface electrode 10 on a part of the Mg-doped p-type contact layer 9, the epitaxial wafer for semiconductor light emitting elements is used. An LED chip was manufactured and its characteristics were evaluated. As a result, compared with a normal Zn-doped LED, the output and operating voltage Vf of the LED remain unchanged at about 2.2 mW and 1.98 V, and the initial output after the continuous energization test is improved and increased by 20%. The reliability was as high as 100.3%.

  In the LED structure using GaP for the Mg-doped p-type current diffusion layer 8 as described above, since there is Zn diffusion of the Zn-doped p-type band discontinuity eliminating layer 6, this Zn-doped p-type band discontinuity eliminating layer 6 It is desirable that the semiconductor layer adjacent to Zn is doped with Zn (Zn-doped p-type current diffusion layer 7).

  The structure of a light emitting diode (LED) according to the second embodiment of the present invention is shown in FIG. In the following description, each layer is described as having a specific conductivity type, but the present invention is not limited to this, and the n-type and p-type semiconductor layers may be reversed.

On the n-type substrate 2 made of GaAs by the MOVPE method, the n-type cladding layer 3 made of Si-doped AlGaInP having a thickness of 0.5 μm and a carrier concentration of 1 × 10 ¹⁸ cm ⁻³ , and undoped having a thickness of 0.5 μm An active layer 4 made of AlGaInP, a Zn-doped p-type cladding layer 5 made of Zn-doped AlGaInP with a thickness of 0.5 μm and a carrier concentration of 5 × 10 ¹⁷ cm ⁻³ , a thickness of 8 μm and a carrier concentration of 3 × 10 ¹⁸ Mg doped p-type current diffusion layer 8 composed of Mg-doped AlGaAs of cm ^-3, a Mg-doped p-contact layer 9 of a carrier concentration in thickness 0.2μm is made of Mg-doped GaAs of 1 × 10 ¹⁹ cm ^-3 sequentially Formed.

  SIMS analysis confirmed that the p-type semiconductor layer contained both Zn and Mg, but neither diffused into the active layer and was an undoped layer.

  An LED chip was manufactured from this epitaxial wafer for a semiconductor light emitting device, and its characteristics were evaluated. As a result, compared with a normal Zn-doped LED, the output of the LED chip and the operating voltage Vf remain unchanged at about 2.1 mW and 1.92 V, and the initial output after the continuous energization test is improved by 20%. High reliability with 100.3% of increase.

[Other Examples, Modifications]
In the above embodiment, the light emitting diode has been described as an example. However, even in the epitaxial structure for a laser diode, if the p-type cladding layer is doped with Zn and an Mg-doped layer is provided thereon, Zn is activated by mutual diffusion. High reliability due to diffusion away from

1 is a cross-sectional view showing a semiconductor light emitting element according to a first embodiment of the present invention. It is sectional drawing which shows the semiconductor light-emitting device concerning 2nd embodiment of this invention. It is sectional drawing which shows the semiconductor light-emitting device concerning 3rd embodiment of this invention.

Explanation of symbols

1 Back electrode 2 n-type substrate 3 n-type cladding layer 4 active layer 5 Zn-doped p-type cladding layer 6 Zn-doped p-type band discontinuity eliminating layer 7 Zn-doped p-type current diffusion layer 8 Mg-doped p-type current diffusion layer 9 Mg Doped p-type contact layer 10 Surface electrode 11 Mg-doped p-type cladding layer

Claims (10)

In a semiconductor light emitting device having a structure in which a light emitting portion is formed by sandwiching an active layer between a first conductive type and a second conductive type cladding layer on a first conductive type substrate,
A p-type semiconductor layer doped with at least zinc is disposed between the p-type semiconductor layer doped with at least magnesium and the active layer;
A semiconductor light emitting device characterized by having a structure in which zinc is diffused farther from the active layer by mutual diffusion of magnesium and zinc. A semiconductor light emitting device having a structure in which a light emitting portion in which an active layer is sandwiched between a first conductive type and a second conductive type cladding layer is formed on a first conductive type substrate, and a second conductive type current spreading layer is formed thereon. In
A p-type semiconductor layer doped with at least zinc is disposed between the p-type semiconductor layer doped with at least magnesium and the active layer;
A semiconductor light emitting device characterized by having a structure in which zinc is diffused farther from the active layer by mutual diffusion of magnesium and zinc. The semiconductor light emitting device according to claim 1 or 2,
A semiconductor light emitting device comprising a p-type semiconductor layer doped with at least magnesium and a p-type semiconductor layer doped with at least zinc. The semiconductor light-emitting device according to claim 1,
A semiconductor light-emitting device, wherein at least zinc is doped in a p-type cladding layer on the side close to the active layer of the first conductivity type and second conductivity type cladding layers constituting the light emitting portion. In the semiconductor light-emitting device according to claim 1,
A semiconductor light emitting element, wherein the first conductivity type substrate is GaAs and the light emitting part is formed of AlGaInP or GaInP. In an epitaxial wafer for a semiconductor light emitting device having a structure in which a light emitting portion is formed by sandwiching an active layer between a first conductive type and a second conductive type cladding layer on a first conductive type substrate,
A p-type semiconductor layer doped with at least zinc is disposed between the p-type semiconductor layer doped with at least magnesium and the active layer;
An epitaxial wafer for a semiconductor light-emitting device, characterized in that zinc is diffused to the side farther from the active layer by mutual diffusion of magnesium and zinc. A semiconductor light emitting device having a structure in which a light emitting portion in which an active layer is sandwiched between a first conductive type and a second conductive type cladding layer is formed on a first conductive type substrate, and a second conductive type current spreading layer is formed thereon. For epitaxial wafers,
A p-type semiconductor layer doped with at least zinc is disposed between the p-type semiconductor layer doped with at least magnesium and the active layer;
An epitaxial wafer for a semiconductor light emitting device, characterized in that zinc is diffused to the side farther from the active layer by mutual diffusion of magnesium and zinc. In the epitaxial wafer for semiconductor light-emitting devices according to claim 6 or 7,
An epitaxial wafer for a semiconductor light emitting device, wherein a p-type semiconductor layer doped with at least magnesium and a p-type semiconductor layer doped with at least zinc are adjacent to each other. In the epitaxial wafer for semiconductor light emitting elements in any one of Claims 6-8,
An epitaxial for a semiconductor light emitting device, wherein at least zinc is doped in a p-type clad layer on the side close to an active layer of the first conductivity type and second conductivity type clad layers constituting the light emitting portion. Wafer. In the epitaxial wafer for semiconductor light emitting elements in any one of Claims 6-9,
An epitaxial wafer for a semiconductor light emitting device, wherein the first conductivity type substrate is GaAs and the light emitting portion is formed of AlGaInP or GaInP.

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