CN211719609U

CN211719609U - Photoelectric device structure

Info

Publication number: CN211719609U
Application number: CN201922263062.2U
Authority: CN
Inventors: 王巧; 刘宁炀; 梁锡辉; 卢瀚仑; 王君君; 林丹
Original assignee: Guangdong Semiconductor Industry Technology Research Institute
Current assignee: Institute of Semiconductors of Guangdong Academy of Sciences
Priority date: 2019-12-16
Filing date: 2019-12-16
Publication date: 2020-10-20
Anticipated expiration: 2029-12-16

Abstract

The application provides a photoelectric device structure, and relates to the technical field of semiconductor photoelectricity. The photoelectric device structure comprises a substrate, a buffer layer, an n-type semiconductor layer and Al which are connected layer by layer_xGa_1‑xN/Al_yGa_1‑yN light emitting active region, last Al_xGa_1‑xAn N quantum barrier layer, a p-type electron barrier layer, a p-type semiconductor layer and a contact layer, wherein x is not less than 0.01<y is less than or equal to 1; the first AlGaN quantum barrier layer in the light-emitting active region is arranged close to the n-type semiconductor layer, and the last quantum well layer in the light-emitting active region is arranged close to the last Al layer_xGa_1‑ _xThe N quantum barrier layer is arranged, and a plurality of AlGaN quantum barrier layers and the last Al_xGa_1‑xThe N quantum barrier layers are all aluminum component gradient layers. The application provides a photoelectric device structure has the advantage that quantum efficiency and luminous efficiency have been promoted.

Description

Photoelectric device structure

Technical Field

The application relates to the technical field of semiconductor photoelectricity, in particular to a photoelectric device structure.

Background

In recent years, the AlGaN-based deep ultraviolet LED has the advantages of environmental protection, no mercury, sterilization, high modulation frequency and the like, and has important commercial application value in the fields of ultraviolet curing, air and water purification, biomedical treatment, high-density storage, safety, secret communication and the like.

However, deep ultraviolet LEDs still exhibit lower radiative recombination and extraction efficiencies relative to more mature blue LEDs. Limiting its output with higher quantum efficiency for reasons including:

1. when the AlGaN-based deep ultraviolet LED epitaxial material grows, a quantum structure with larger strain generates excessive dislocation density, and a non-radiative recombination center is formed, so that the efficiency is reduced;

2. p-type doping is difficult, Mg in high Al components is very difficult to incorporate, and the activation efficiency is lower than 1%;

3. one key factor limiting the luminous efficiency of the AlGaN-based LED is electron current leakage caused by mismatching of electron hole injection under a high-current condition, and partial electrons cannot be sufficiently recombined to emit light in a light-emitting active region but leak from the active region to a p-type region, which makes the hole injection deficiency and the electron leakage of the AlGaN-based deep ultraviolet LED with a high Al composition more serious.

The reason is that the activation energy of Mg in AlGaN is as high as 510-600meV, so that the hole concentration of P-type AlGaN is far lower than that of n-type AlGaN, and a large amount of electrons are leaked from a quantum well into a P-type region and are lost. These leaked electrons also reduce the radiative recombination efficiency of the carriers, which in turn reduces the deep ultraviolet LED extraction efficiency.

In summary, the AlGaN-based deep ultraviolet LED has the problems of low recombination efficiency and low light extraction efficiency.

SUMMERY OF THE UTILITY MODEL

An object of the application is to provide a photoelectric device structure to solve the lower problem of compound efficiency and luminous efficiency of AlGaN base deep ultraviolet LED among the prior art.

In order to achieve the above purpose, the embodiments of the present application employ the following technical solutions:

in one aspect, an embodiment of the present application provides an optoelectronic device structure, which includes a substrate, a buffer layer, an n-type semiconductor layer, and Al, connected layer by layer_xGa_1-xN/Al_yGa_1-yN light emitting active region, last Al_xGa_1-xAn N quantum barrier layer, a p-type electron barrier layer, a p-type semiconductor layer and a contact layer, wherein x is not less than 0.01<y≤1；

Wherein said Al is_xGa_1-xN/Al_yGa_1-yThe N light-emitting active region comprises a plurality of quantum well layers and a plurality of AlGaN quantum barrier layers, wherein the quantum well layers and the AlGaN quantum barrier layers are alternately arranged, so that the first AlGaN quantum barrier layer in the light-emitting active region is arranged close to the N-type semiconductor layer, and the last quantum well layer in the light-emitting active region is arranged close to the last Al quantum barrier layer_xGa_1-xThe N quantum barrier layer is arranged, and the plurality of AlGaN quantum barrier layers and the last Al layer_xGa_1-xThe N quantum barrier layers are all aluminum component gradient layers.

Further, the Al_xGa_1-xN/Al_yGa_1-yThe N light-emitting active region comprises N quantum well layers and N AlGaN quantum barrier layers, wherein N is more than or equal to 2 and less than or equal to 20;

wherein the aluminum composition in the N quantum well layers is constant, and the N quantum well layers and the N AlGaN quantum barrier layers are alternately arranged;

each of AlGaN quantum barrier layer and the last Al_xGa_1-xThe aluminum component in the N quantum barrier layer changes linearly or nonlinearly in the growth direction.

Further, each AlGaN quantum barrier layer and the last Al_xGa_1-xThe aluminum components in the N quantum barrier layers are increased gradually, decreased gradually, increased gradually and decreased gradually in the growth direction.

Further, each AlGaN quantum barrier layer and the last Al_xGa_1-xThe initial value of the aluminum component in the N quantum barrier layer in the growth direction is a₁And increases to b along the growth direction₁Then decreases to a₁Is further increased by b₁Then decreases to a₁。

Further, each AlGaN quantum barrier layer and the last Al_xGa_1-xThe N quantum barrier layers are all Al_0.53Ga_0.47N/Al_aGa_1-aN/Al_bGa_1-bN/Al_aGa_1-aN/Al_bGa_1-bN/Al_0.53Ga_0.47An N structure, wherein, a is more than or equal to 0.53<b is less than or equal to 1, and a and b are gradually changed.

Further, each AlGaN quantum barrier layer and the last Al_xGa_1-xThe thickness of the N quantum barrier layers is 5-100 nm.

Further, each AlGaN quantum barrier layer and the last Al_xGa_1-xThe highest aluminum component value in the N quantum barrier layer is less than or equal to the aluminum component value in the p-type electron barrier layer;

each AlGaN quantum barrier layer and the last Al_xGa_1-xThe lowest aluminum component value in the N quantum barrier layer is larger than that in the quantum well layer.

Further, the buffer layer includes an AlN buffer layer; the n-type semiconductor layer includes an n-type AlGaN layer; the p-type electron blocking layer comprises a p-type AlGaN electron blocking layer; the p-type semiconductor layer includes a p-type AlGaN layer.

Further, the substrate is any one of a sapphire substrate, a SiC substrate, a Si substrate, and a GaN substrate.

In another aspect, an embodiment of the present application further provides a method for manufacturing an optoelectronic device structure, where the method is used to manufacture the optoelectronic device structure described above, and the method includes:

growing a buffer layer, an n-type semiconductor layer and Al in sequence along the surface of a substrate_xGa_1-xN/Al_yGa_1-yN light emitting active region, last Al_xGa_1-xAn N quantum barrier layer, a p-type electron barrier layer, a p-type semiconductor layer and a contact layer, wherein x is more than or equal to 0.01<y≤1；

And Al_xGa_1-xN/Al_yGa_1-yA plurality of quantum well layers and a plurality of AlGaN quantum barrier layers in an N light emitting active region, wherein the plurality of AlGaN quantum barrier layers and the last Al layer are grown_xGa_1-xThe N quantum barrier layer comprises the following steps:

in the reaction chamber, the temperature is adjusted to a target temperature, and the flow of the Al source and the Ga source is adjusted to gradually change along with the growth time so as to grow a plurality of AlGaN quantum barrier layers with gradually changed aluminum components and the last Al_xGa_1-xAnd an N quantum barrier layer.

Compared with the prior art, the method has the following beneficial effects:

the embodiment of the application provides a photoelectric device structure which comprises a substrate, a buffer layer, an n-type semiconductor layer and Al, wherein the substrate, the buffer layer, the n-type semiconductor layer and the Al are connected layer by layer_xGa_1-xN/Al_yGa_1-yN light emitting active region, last Al_xGa_1-xAn N quantum barrier layer, a p-type electron barrier layer, a p-type semiconductor layer and a contact layer, wherein x is not less than 0.01<y is less than or equal to 1; wherein, Al_xGa_1-xN/Al_yGa_1-yThe N light-emitting active region comprises a plurality of quantum well layers and a plurality of AlGaN quantum barrier layers, wherein the quantum well layers and the AlGaN quantum barrier layers are alternately arranged, so that the first AlGaN quantum barrier layer in the light-emitting active region is arranged close to the N-type semiconductor layer, and the last quantum well layer in the light-emitting active region is arranged close to the last Al layer_xGa_1-xThe N quantum barrier layer is arranged, and a plurality of AlGaN quantum barrier layers and the last oneAl (B) in_xGa_1-xThe N quantum barrier layers are all aluminum component gradient layers. Because the band structure of the AlGaN-based semiconductor deep ultraviolet device is optimized, a plurality of AlGaN quantum barrier layers and the last Al layer are arranged_xGa_1-xThe N quantum barrier layers are aluminum component gradient layers, and compared with a common ultraviolet structure, the structure of the AlGaN-based semiconductor ultraviolet device can effectively increase the electron limiting effect and enhance the hole injection efficiency through the change of the structure, so that the quantum efficiency and the luminous efficiency of the AlGaN-based semiconductor ultraviolet device are improved.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and it will be apparent to those skilled in the art that other related drawings can be obtained from the drawings without inventive effort.

Fig. 1 is a schematic cross-sectional view of an optoelectronic device structure provided in an embodiment of the present application.

Fig. 2 is a graph comparing the electroluminescence spectra of a photovoltaic device structure according to an embodiment of the present application with a conventional structure.

Fig. 3 is a diagram of one of the quantum barrier layer structure designs provided in the present application.

Fig. 4 is a second design of a quantum barrier layer structure according to the present embodiment.

Fig. 5 is a third design of a quantum barrier layer structure according to the present embodiment.

Fig. 6 is a fourth design of quantum barrier layer structure according to the present embodiment.

In the figure: 100-an optoelectronic device structure; 110-a substrate; 120-a buffer layer; a 130-n type semiconductor layer; 140-Al_xGa_1- _xN/Al_yGa_1-yAn N light emitting active region; 141-AlGaN quantum barrier layers; 142-a quantum well layer; 150-last Al_xGa_1-xAn N quantum barrier layer; a 160-p type electron blocking layer; 170-p type semiconductor layer; 180-contact layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally found in use of products of the application, and are used only for convenience in describing the present application and for simplification of description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application.

In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

As described in the background art, the AlGaN-based deep ultraviolet LED has a problem of low recombination efficiency and light extraction efficiency.

The reason is that the traditional AlGaN-based semiconductor ultraviolet device has the following structure: a substrate, a buffer layer, an n-type layer, a light emitting active region, a p-type electron blocking layer 160, a p-type layer, and a contact layer. And the barrier layer in the quantum well and the well layer are constant in aluminum composition. Under this structure, hole injection is insufficient and electron leakage is severe in the light emitting active region.

In view of this, in order to promote the recombination efficiency and the light extraction efficiency of the AlGaN-based deep ultraviolet LED, the present application provides a photoelectric device structure by optimizing the quantum barrier layer of the active region and the light extraction efficiencyLast Al_xGa_1-xThe structure of N quantum barrier layer, and then optimize this photoelectric device's energy band structure, effectively promote photoelectric device's compound efficiency and luminous efficiency.

The optoelectronic device structure provided in the present application is schematically illustrated below:

referring to fig. 1 and fig. 2, as an alternative implementation, the optoelectronic device structure 100 includes a substrate 110, a buffer layer 120, an n-type semiconductor layer 130, and Al connected in a layer-by-layer manner_xGa_1-xN/Al_yGa_1-yN light emitting active region 140, last Al_xGa_1-xAn N quantum barrier layer 150, a p-type electron barrier layer 160, a p-type semiconductor layer 170 and a contact layer 180, and x is more than or equal to 0.01<y≤1。

Wherein, Al_xGa_1-xN/Al_yGa_1-yThe N light emitting active region 140 includes a plurality of quantum well layers 142 and a plurality of AlGaN quantum barrier layers 141, the quantum well layers 142 and the AlGaN quantum barrier layers 141 are alternately disposed, so that a first AlGaN quantum barrier layer 141 in the light emitting active region is disposed near the N-type semiconductor layer 130, a last quantum well layer 142 in the light emitting active region is disposed near a last AlxGa1-xN quantum barrier layer 150, and the AlGaN quantum barrier layers 141 and the last AlxGa1-xN quantum barrier layer 150150 are aluminum composition gradient layers.

By arranging the plurality of AlGaN quantum barrier layers 141 and the last AlxGa1-xN quantum barrier layer 150 as aluminum component gradient layers, the band structure of the device can be optimized, the electron confinement effect is effectively increased, and the hole injection efficiency is enhanced, so that the quantum efficiency and the luminous efficiency of the AlGaN-based semiconductor ultraviolet device are improved.

Optionally, the substrate 110 provided in the present application is any one of a sapphire substrate, a SiC substrate, a Si substrate, and a GaN substrate, and the buffer layer 120 may be an AlN buffer layer; the n-type semiconductor layer 130 may be an n-type AlGaN layer; the p-type electron blocking layer 160 may be a p-type AlGaN electron blocking layer; the p-type semiconductor layer 170 may be a p-type AlGaN layer.

The light emitting principle of the optoelectronic device structure 100 is as follows:

electrons and p-type provided by n-type AlGaN layerHoles provided in the AlGaN layer are in Al_xGa_1-xN/Al_yGa_1-yN140 emits light in combination. Wherein, the p-type AlGaN electron blocking layer can play a role in blocking Al_xGa_1-xN/Al_yGa_1-yElectrons in N140 enter the p-type AlGaN layer, and recombination of electrons and holes in the p-type AlGaN layer is prevented.

Wherein, Al_xGa_1-xN/Al_yGa_1-yThe N140 comprises N quantum well layers 142 and N AlGaN quantum barrier layers 141, wherein N is more than or equal to 2 and less than or equal to 20.

Wherein, the aluminum composition in the N quantum well layers 142 is constant, and the N quantum well layers 142 and the N AlGaN quantum barrier layers 141 are alternately arranged; and each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe aluminum component in the N quantum barrier layer 150 changes linearly or nonlinearly in the growth direction.

As one implementation, the application takes Al_xGa_1-xN/Al_yGa_1-yThe N140 includes 5 quantum well layers 142 and 5 AlGaN quantum barrier layers 141 for illustration.

That is, the first AlGaN quantum barrier layer 141 is connected to the n-type semiconductor layer 130, the first quantum well layer 142 is connected to the first AlGaN quantum barrier layer 141, the second AlGaN quantum barrier layer 141 is connected to the first quantum well layer 142, and so on until the fifth quantum well layer 142 is connected. The last Al is then connected on the fifth quantum well layer 142_xGa_1-xAnd an N quantum barrier layer 150.

As an alternative implementation, please refer to FIG. 3, Al_xGa_1-xN/Al_yGa_1-yAlGaN quantum barrier layer 141 and the last Al in N140_xGa_1-xThe aluminum component in the N quantum barrier layer 150 is in a double triangle structure, i.e., each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe aluminum components in the N quantum barrier layer 150 all increase gradually, then decrease gradually, then increase gradually, and then decrease gradually in the growth direction.

By mixing Al_xGa_1-xN/Al_yGa_1-yAlGaN quantum barrier layer 141 in N140 and the top layerThe latter Al_xGa_1-xThe aluminum component in the N quantum barrier layer 150 is changed in a double triangle, so that the optoelectronic device structure 100 provided by the present application has the following beneficial effects:

first, the last Al can be eliminated_xGa_1-xThe polarized charges at the interface between the N quantum barrier layer and the p-type electron blocking layer 160 eliminate the electron concentration at the interface (the electrons concentrated at the interface are not beneficial to light emission), thereby improving the light emitting efficiency.

Second, negative body polarization charges are spontaneously formed in the double-triangular AlGaN quantum barrier layer 141 in the light emitting active region, and the body polarization charges can cause the last Al_xGa_1-xThe conduction band near the interface of the N quantum barrier layer and the electron barrier layer is increased, so that the electron blocking effect can be enhanced, and the electron leakage is reduced.

Third, last Al of triangular variation_xGa_1-xNegative body polarization charges can be spontaneously formed in the N quantum barrier layers, and then high hole concentration can be induced.

As an optional implementation manner, each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xTwo triangles formed by the aluminum components in the N quantum barrier layer 150 in the growth direction are consistent. For example, each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe initial value of the aluminum component in the N quantum barrier layer 150 in the growth direction is a₁And increases to b along the growth direction₁Then decreases to a₁Is further increased by b₁Then decreases to a₁。

That is, in the process of manufacturing the photoelectric device, when the AlGaN quantum barrier layer 141 is epitaxially grown on the n-type AlGaN layer, the value of the aluminum component is first set to a₁And gradually increasing the value of the aluminum component until the value of the aluminum component is increased to b in the process of epitaxy₁And in the protocol of continued epitaxy, the value of the aluminium composition is gradually reduced here, and so on.

The following are specifically exemplified:

each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xN quantum barrier layer150 is Al_0.53Ga_0.47N/Al_aGa_1-aN/Al_bGa_1-bN/Al_aGa_1-aN/Al_bGa_1-bN/Al_0.53Ga_0.47An N structure, wherein, a is more than or equal to 0.53<b is less than or equal to 1, and a and b are gradually changed.

As another optional implementation manner, please refer to fig. 4 and 5, each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xTwo triangles formed by the aluminum component in the N quantum barrier layer 150 in the growth direction may also be inconsistent. For example, each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe initial value of the aluminum component in the N quantum barrier layer 150 in the growth direction is a₁And increases to b along the growth direction₁Then decreases to a₁Is further increased by b₂Then decreases to a₁。

Of course, referring to fig. 6, in other embodiments, each AlGaN quantum barrier layer 141 and the last Al layer_xGa_1-xThe shape formed by the change of the aluminum component in the N quantum barrier layer 150 may also be a double trapezoid, which is not limited in this application.

It should be noted that, in the present application, each AlGaN quantum barrier layer 141 and the last Al are provided_xGa_1-xThe highest aluminum component value in the N quantum barrier layer 150 is less than or equal to the aluminum component value in the p-type electron blocking layer 160; each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe lowest aluminum component value in the N quantum barrier layer 150 is greater than the aluminum component value in the quantum well layer 142.

And, each AlGaN quantum barrier layer 141 and the last Al_xGa_1-xThe thickness of the N quantum barrier layer 150 is 5-100 nm.

Moreover, the optoelectronic device structure 100 provided by the present application can be applied to LEDs with a structure of a front mount, a flip-chip, a vertical structure, and the like. And the optoelectronic device structure 100 can be adapted to LED structures of all emission wavelengths.

In summary, the present application introduces the variation of aluminum composition into the double triangle by optimizing the energy band structure of the AlGaN-based semiconductor deep ultraviolet deviceThe structure is taken as the last Al_xGa_1-xThe N quantum barrier layer simultaneously transits a novel quantum barrier structure to the structure of a quantum barrier in the whole active region, and compared with a common ultraviolet structure, the change of the structure optimizes the energy band structure of the device, can effectively increase the electron limiting effect and enhance the hole injection efficiency, thereby improving the quantum efficiency and the luminous efficiency of the AlGaN-based semiconductor ultraviolet device, and is particularly more effective to the AlGaN-based semiconductor ultraviolet light-emitting device under high injection.

Based on the optoelectronic device structure 100, an embodiment of the present application further provides a method for manufacturing the optoelectronic device structure 100, where the method includes:

growing a buffer layer 120, an n-type semiconductor layer 130, and Al in sequence along the surface of a substrate 110_xGa_1-xN/Al_yGa_1- _yN140, last Al_xGa_1-xAn N quantum barrier layer 150, a p-type electron barrier layer 160, a p-type semiconductor layer 170 and a contact layer 180, wherein x is more than or equal to 0.01<y≤1。

And, Al_xGa_1-xN/Al_yGa_1-yN140 multiple quantum well layers 142 and multiple AlGaN quantum barrier layers 141, wherein multiple AlGaN quantum barrier layers 141 and the last Al layer are grown_xGa_1-xThe N quantum barrier layer 150 includes the steps of:

in the reaction chamber, the temperature is adjusted to the target temperature, and the flow of the Al source and the Ga source is adjusted to gradually change along with the growth time, so as to grow a plurality of AlGaN quantum barrier layers 141 with gradually changed aluminum components and the last Al_xGa_1-xAnd an N quantum barrier layer 150.

As an implementation manner, the AlGaN quantum barrier layer 141 is grown by Metal Organic Chemical Vapor Deposition (MOCVD), and the target temperature may be 900 to 1200 ℃.

In summary, the embodiments of the present application provide a photoelectric device structure, which includes a substrate, a buffer layer, an n-type semiconductor layer, and Al, connected layer by layer_xGa_1-xN/Al_yGa_1-yN light emitting active region, last Al_xGa_1-xN quantum barrier layer, pA type electron blocking layer, a p-type semiconductor layer and a contact layer, and x is not less than 0.01<y is less than or equal to 1; wherein, Al_xGa_1-xN/Al_yGa_1-yThe N light-emitting active region comprises a plurality of quantum well layers and a plurality of AlGaN quantum barrier layers, wherein the quantum well layers and the AlGaN quantum barrier layers are alternately arranged, so that the first AlGaN quantum barrier layer in the light-emitting active region is arranged close to the N-type semiconductor layer, and the last quantum well layer in the light-emitting active region is arranged close to the last Al layer_xGa_1-xThe N quantum barrier layer is arranged, and a plurality of AlGaN quantum barrier layers and the last Al_xGa_1-xThe N quantum barrier layers are all aluminum component gradient layers. Because the band structure of the AlGaN-based semiconductor deep ultraviolet device is optimized, a plurality of AlGaN quantum barrier layers and the last Al layer are arranged_xGa_1-xThe N quantum barrier layers are aluminum component gradient layers, and compared with a common ultraviolet structure, the structure of the AlGaN-based semiconductor ultraviolet device can effectively increase the electron limiting effect and enhance the hole injection efficiency through the change of the structure, so that the quantum efficiency and the luminous efficiency of the AlGaN-based semiconductor ultraviolet device are improved.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

It will be evident to those skilled in the art that the present application is not limited to the details of the foregoing illustrative embodiments, and that the present application may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. A photoelectric device structure is provided, which comprises a substrate,the photoelectric device structure is characterized by comprising a substrate, a buffer layer, an n-type semiconductor layer and Al which are connected layer by layer_xGa_1-xN/Al_yGa_1-yN light emitting active region, last Al_xGa_1-xAn N quantum barrier layer, a p-type electron barrier layer, a p-type semiconductor layer and a contact layer, wherein x is not less than 0.01<y≤1；

2. The optoelectronic device structure of claim 1, wherein the Al is_xGa_1-xN/Al_yGa_1-yThe N light-emitting active region comprises N quantum well layers and N AlGaN quantum barrier layers, wherein N is more than or equal to 2 and less than or equal to 20;

each AlGaN quantum barrier layer and the last Al_xGa_1-xThe aluminum component in the N quantum barrier layer changes linearly or nonlinearly in the growth direction.

3. The optoelectronic device structure of claim 2, wherein each of the AlGaN quantum barrier layers and the last Al layer_xGa_1-xThe aluminum components in the N quantum barrier layers are increased gradually, decreased gradually, increased gradually and decreased gradually in the growth direction.

4. The optoelectronic device structure according to claim 3, characterized in thatCharacterized in that each AlGaN quantum barrier layer and the last Al_xGa_1-xThe initial value of the aluminum component in the N quantum barrier layer in the growth direction is a₁And increases to b along the growth direction₁Then decreases to a₁Is further increased by b₁Then decreases to a₁。

5. The optoelectronic device structure of claim 3, wherein each of the AlGaN quantum barrier layers and the last Al layer_xGa_1-xThe N quantum barrier layers are all Al_0.53Ga_0.47N/Al_aGa_1-aN/Al_bGa_1-bN/Al_aGa_1-aN/Al_bGa_1-bN/Al_0.53Ga_0.47An N structure, wherein, a is more than or equal to 0.53<b is less than or equal to 1, and a and b are gradually changed.

6. The optoelectronic device structure of claim 1, wherein each of the AlGaN quantum barrier layers and the last Al layer_xGa_1-xThe thickness of the N quantum barrier layers is 5-100 nm.

7. The optoelectronic device structure of claim 1, wherein each of the AlGaN quantum barrier layers and the last Al layer_xGa_1-xThe highest aluminum component value in the N quantum barrier layer is less than or equal to the aluminum component value in the p-type electron barrier layer;

8. The optoelectronic device structure of claim 1, wherein the buffer layer comprises an AlN buffer layer; the n-type semiconductor layer includes an n-type AlGaN layer; the p-type electron blocking layer comprises a p-type AlGaN electron blocking layer; the p-type semiconductor layer includes a p-type AlGaN layer.

9. The optoelectronic device structure according to claim 1, wherein the substrate is any one of a sapphire substrate, a SiC substrate, a Si substrate, and a GaN substrate.