Light-emitting diode epitaxial wafer, preparation method thereof and LED

Abstract

The invention relates to the technical field of photoelectricity, and discloses a light-emitting diode epitaxial wafer and a preparation method thereof, and an LED, the light-emitting diode epitaxial wafer comprises a substrate, and the substrate is sequentially provided with a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer; the multi-quantum well layer comprises quantum well layers and quantum barrier layers which are sequentially and alternately stacked, and the quantum barrier layers comprise at least one group of first GaN layer, AlN layer, InN layer and second GaN layer which are sequentially stacked. The light-emitting diode epitaxial wafer provided by the invention can improve the wavelength consistency and reduce the blue shift of the wavelength.

Description

Technical Field

[0001] The invention relates to the field of optoelectronic technology, and in particular to a light emitting diode epitaxial wafer and a preparation method thereof, and an LED. Background Art

[0002] LED chips are semiconductor electronic components that can emit light. They are small in size, high in brightness, and low in energy consumption. They are widely used in lighting and other fields. LED chips are obtained by splitting LED epitaxial wafers. LED epitaxial wafers include a substrate and a GaN epitaxial layer grown on the substrate.

[0003] At present, materials such as sapphire, silicon or silicon carbide are often used as substrates. With the application of LED in different fields, the requirements for chip performance have also been emphasized. For example, the application in the display field requires chip consistency, especially the consistency under different current drives. As the wavelength of LED chips will blue shift as the applied current increases, if the chips are very different, the amplitude of the wavelength blue shift will also be different, so the difference in wavelength will be amplified, and ultimately cause color difference to affect the display effect. Therefore, the consistency of LED chips is a very important technical indicator at present, and the wavelength is determined by epitaxy. Growing highly uniform epitaxial wafers is a technical difficulty that urgently needs to be overcome. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a light emitting diode epitaxial wafer which can improve the wavelength consistency and reduce the blue shift of the wavelength.

[0005] The technical problem to be solved by the present invention is to provide a method for preparing a light emitting diode epitaxial wafer, which has a simple process and can stably prepare a light emitting diode epitaxial wafer with good luminous efficiency.

[0006] In order to solve the above technical problems, the present invention provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially arranged;

[0007] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes at least one group of a first GaN layer, an AlN layer, an InN layer, and a second GaN layer that are alternately stacked in sequence.

[0008] In some embodiments, the quantum barrier layer includes 1 to 5 groups of a first GaN layer, an AlN layer, an InN layer, and a second GaN layer stacked in sequence.

[0009] In some embodiments, the quantum barrier layer has a thickness of 8 nm to 12 nm.

[0010] In some embodiments, the thickness of the first GaN layer is 0.1 nm to 5 nm.

[0011] In some embodiments, the second GaN layer has a thickness of 0.1 nm to 5 nm.

[0012] In some embodiments, the AlN layer has a thickness of 0.1 nm to 3 nm.

[0013] In some embodiments, the thickness of the InN layer is 0.1 nm to 3 nm.

[0014] In some embodiments, the quantum well layer is an InGaN layer.

[0015] To solve the above problems, the present invention also provides a method for preparing a light emitting diode epitaxial wafer, comprising the following steps:

[0016] S1. providing a substrate;

[0017] S2, depositing a buffer layer, an undoped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer on the substrate in sequence;

[0018] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes at least one group of a first GaN layer, an AlN layer, an InN layer, and a second GaN layer that are alternately stacked in sequence.

[0019] Correspondingly, the present invention further provides an LED, which includes the light-emitting diode epitaxial wafer as described above, or includes the light-emitting diode epitaxial wafer manufactured by the method for manufacturing the light-emitting diode epitaxial wafer as described above.

[0020] The implementation of the present invention has the following beneficial effects:

[0021] In the light-emitting diode epitaxial wafer provided by the present invention, by designing a quantum barrier layer of a composite structure, compared with the quantum barrier layer of a traditional single-layer structure, stress can be better released and electron overflow can be more effectively blocked, thereby improving current expansion. Since Ga atoms, Al atoms, and In atoms have different diameters, Al atoms are the smallest and Ga atoms are the largest, the GaN / AlN / InN / GaN stack can fill gaps and improve the direction of defect extension, thereby releasing stress to a certain extent, so that a more uniform In component distribution can be achieved in the subsequent growth quantum well layer. In addition, the potential barrier of AlN is higher, and the potential barrier of InN is lower. The stack of GaN / AlN / InN / GaN can form a stepped barrier, and electrons need to obtain more energy to overflow, so the overflow of current can be better limited. Improvement and expansion. Through the above two effects, the In component distribution in the quantum well can be improved, the electron overflow can be reduced, and the current expansion can be improved, thereby improving the wavelength consistency and reducing the blue shift of the wavelength. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of the light emitting diode epitaxial wafer provided by the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. In addition, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] In the description of the present invention, it is necessary to understand that the terms "length", "width", "up", "down", "left", "right", "horizontal", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the examples of various specific processes and materials provided by the present invention, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0029] In the present invention, "preferred" and "better" are only used to describe implementation methods or embodiments with better effects, and it should be understood that they do not constitute a limitation on the scope of protection of the present invention. In the present invention, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features. In the present invention, when involving numerical ranges, unless otherwise specified, the two endpoints of the numerical range are included.

[0030] To solve the above problems, the present invention provides a light emitting diode epitaxial wafer, such as Figure 1 As shown, it includes a substrate 100, on which a buffer layer 200, a non-doped GaN layer 300, an N-type GaN layer 400, a stress release layer 500, a multi-quantum well layer 600, an electron blocking layer 700, and a P-type GaN layer 800 are sequentially arranged;

[0031] The multi-quantum well layer 600 includes quantum well layers 610 and quantum barrier layers 620 that are alternately stacked in sequence. The quantum barrier layer 620 includes at least one group of a first GaN layer 621 , an AlN layer 622 , an InN layer 623 , and a second GaN layer 624 that are alternately stacked in sequence.

[0032] The specific structure of the quantum barrier layer 620 provided by the present invention is as follows:

[0033] In some embodiments, the multi-quantum well layer 600 includes 1 to 20 groups of quantum well layers 610 and quantum barrier layers 620 that are alternately stacked in sequence; the quantum well layer 610 is an InGaN layer; the quantum barrier layer 620 includes 1 to 5 groups of first GaN layer 621, AlN layer 622, InN layer 623 and second GaN layer 624 that are stacked in sequence.

[0034] In some embodiments, the thickness of the quantum well layer 610 is 2nm to 5nm; exemplary thicknesses of the quantum well layer 610 are 2nm, 3nm, and 4nm, not limited to the above. The thickness of the quantum barrier layer 620 is 8nm to 12nm. Exemplary thicknesses of the quantum barrier layer 620 are 9nm, 10nm, and 11nm, not limited to the above.

[0035] In some embodiments, the thickness of the first GaN layer 621 is 0.1 nm to 5 nm; exemplary thicknesses of the first GaN layer 621 are 0.5 nm, 1 nm, 1.5 nm, 2 nm, 2.5 nm, 3 nm, 3.5 nm, 4 nm, and 4.5 nm, but are not limited to the above list.

[0036] In some embodiments, the thickness of the AlN layer 622 is 0.1 nm to 3 nm; exemplary thicknesses of the AlN layer 622 are 0.5 nm, 1 nm, 1.5 nm, 2 nm, and 2.5 nm, but are not limited to the above examples.

[0037] In some embodiments, the thickness of the InN layer 623 is 0.1 nm to 3 nm; exemplary thicknesses of the InN layer 623 are 0.5 nm, 1 nm, 1.5 nm, 2 nm, and 2.5 nm, but are not limited to the above examples.

[0038] In some embodiments, the thickness of the second GaN layer 624 is 0.1 nm to 5 nm; exemplary thicknesses of the second GaN layer 624 are 0.5 nm, 1 nm, 1.5 nm, 2 nm, 2.5 nm, 3 nm, 3.5 nm, 4 nm, and 4.5 nm, but are not limited to the above list.

[0039] In the light-emitting diode epitaxial wafer provided in the above embodiment, by designing a quantum barrier layer of a composite structure, compared with the quantum barrier layer of a traditional single-layer structure, stress can be better released and electron overflow can be more effectively blocked, thereby improving current expansion. Since the diameters of Ga atoms, Al atoms, and In atoms are different, Al atoms are the smallest and Ga atoms are the largest, the GaN / AlN / InN / GaN stack can fill the gaps and improve the defect extension direction, thereby releasing stress to a certain extent, so that a more uniform In component distribution can be achieved in the subsequent growth of the quantum well layer. In addition, the potential barrier of AlN is higher and the potential barrier of InN is lower. The GaN / AlN / InN / GaN stack can form a stepped barrier. Electrons need to obtain more energy to overflow, so the overflow of current can be better limited and the expansion can be improved. Through the above two effects, the In component distribution in the quantum well can be improved, the electron overflow can be reduced, and the current expansion can be improved, thereby improving the wavelength consistency and reducing the blue shift of the wavelength.

[0040] Accordingly, the present invention provides a method for preparing a light emitting diode epitaxial wafer, comprising the following steps:

[0041] S1, providing a substrate 100;

[0042] In some embodiments, the substrate 100 may be selected from one of a sapphire substrate, a SiO2 sapphire composite substrate, a silicon substrate, a silicon carbide substrate, a gallium nitride substrate, and a zinc oxide substrate. Preferably, the substrate 100 is a sapphire substrate, which is a commonly used GaN-based LED substrate material. The sapphire substrate has a mature preparation process, a low price, is easy to clean and handle, and has good stability at high temperatures.

[0043] S2, sequentially depositing a buffer layer 200, a non-doped GaN layer 300, an N-type GaN layer 400, a stress release layer 500, a multi-quantum well layer 600, an electron blocking layer 700, and a P-type GaN layer 800 on the substrate 100;

[0044] The multi-quantum well layer 600 includes quantum well layers 610 and quantum barrier layers 620 that are alternately stacked in sequence. The quantum barrier layer 620 includes at least one group of a first GaN layer 621 , an AlN layer 622 , an InN layer 623 , and a second GaN layer 624 that are alternately stacked in sequence.

[0045] Specifically, the above step S2 specifically includes the following steps:

[0046] S21 , depositing the buffer layer 200 on the substrate 100 .

[0047] In some embodiments, the buffer layer 200 is an AlN buffer layer.

[0048] S22 , depositing the undoped GaN layer 300 on the buffer layer 200 .

[0049] In some embodiments, the temperature of the reaction chamber is controlled at 1050° C. to 1200° C., the pressure is controlled at 100 torr to 600 torr, N source and Ga source are introduced, and a non-doped GaN layer with a thickness of 1 μm to 5 μm is grown.

[0050] S23 , depositing the N-type GaN layer 400 on the undoped GaN layer 300 .

[0051] In some embodiments, the temperature of the reaction chamber is controlled at 1050° C. to 1200° C., the pressure is controlled at 100 torr to 600 torr, and an N source, a Ga source, and a Si source are introduced to grow the N-type GaN layer.

[0052] S24 , depositing the stress release layer 500 on the N-type GaN layer 400 .

[0053] In some embodiments, the temperature of the reaction chamber is controlled at 700° C. to 900° C., the pressure is controlled at 50 torr to 600 torr, N source, Ga source, and In source are introduced, and a periodic structure of alternating InGaN layers and GaN layers is grown as a stress release layer.

[0054] S25 , depositing the multi-quantum well layer 600 on the stress release layer 500 .

[0055] In some embodiments, the growth temperature is 850°C to 950°C, the growth pressure is 100torr to 300torr, the MO source is TEGa, TMIn and TMAl, the gases introduced into the growth of GaN layer are N2, H2 and NH3, NH3 is used as the reaction gas, N2 is used as the carrier gas, and H2 is used as the reducing gas to improve the crystal quality; the gases introduced into the growth of AlN layer and InN layer are N2 and NH3, and H2 needs to be turned off. Because TMAl and TMIn will have a strong pre-reaction in the H2 atmosphere, Al atoms and In atoms are decomposed and taken away before they are combined with N atoms, and cannot form AlN and InN layers.

[0056] S26, depositing the electron blocking layer 700 on the multi-quantum well layer 600;

[0057] In some embodiments, the temperature of the reaction chamber is controlled at 900° C. to 1000° C., the pressure is controlled at 100 torr to 300 torr, N source, Al source, Ga source, and In source are introduced to grow an AlInGaN electron blocking layer with a thickness of 10 nm to 40 nm.

[0058] S27 , depositing the P-type GaN layer 800 on the electron blocking layer 700 .

[0059] In some embodiments, the temperature of the reaction chamber is controlled at 900° C. to 1050° C., the pressure is controlled at 100 torr to 600 torr, and an N source, a Mg source, and a Ga source are introduced to grow the P-type GaN layer.

[0060] Accordingly, the present invention further provides an LED, which comprises the above-mentioned light-emitting diode epitaxial wafer, wherein the photoelectric efficiency of the LED is effectively improved and other electrical properties are good.

[0061] The present invention is further described below with specific embodiments:

[0062] Example 1

[0063] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0064] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes a group of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The thickness of the first GaN layer is 4nm, the thickness of the second GaN layer is 4nm, the thickness of the AlN layer is 1nm, the thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0065] Example 2

[0066] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0067] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes two groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 1nm, the total thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0068] Example 3

[0069] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0070] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 1nm, the total thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0071] Example 4

[0072] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0073] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes 4 groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 1nm, the total thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0074] Example 5

[0075] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0076] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes 5 groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 1nm, the total thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0077] Example 6

[0078] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0079] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 0.5nm, the total thickness of the InN layer is 1.5nm, and the quantum well layer is an InGaN layer.

[0080] Example 7

[0081] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0082] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 4nm, the total thickness of the second GaN layer is 4nm, the total thickness of the AlN layer is 1.5nm, the total thickness of the InN layer is 0.5nm, and the quantum well layer is an InGaN layer.

[0083] Example 8

[0084] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0085] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 3nm, the total thickness of the second GaN layer is 3nm, the total thickness of the AlN layer is 2nm, the total thickness of the InN layer is 2nm, and the quantum well layer is an InGaN layer.

[0086] Example 9

[0087] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0088] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 3nm, the total thickness of the second GaN layer is 3nm, the total thickness of the AlN layer is 1nm, the total thickness of the InN layer is 3nm, and the quantum well layer is an InGaN layer.

[0089] Example 10

[0090] This embodiment provides a light-emitting diode epitaxial wafer, comprising a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially provided;

[0091] The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes three groups of first GaN layers, AlN layers, InN layers, and second GaN layers that are stacked in sequence. The total thickness of the first GaN layer is 3nm, the total thickness of the second GaN layer is 3nm, the total thickness of the AlN layer is 3nm, the total thickness of the InN layer is 1nm, and the quantum well layer is an InGaN layer.

[0092] Comparative Example 1

[0093] This comparative example provides a light emitting diode epitaxial wafer, which is different from the other embodiment 1 in that: its quantum barrier layer is a GaN layer with a thickness of 10 nm, and the rest is the same as the embodiment 1.

[0094] The light-emitting diode epitaxial wafers prepared in Example 10 and Comparative Example 1 were prepared into 5 mil×8 mil chips using the same chip process conditions. 300 LED chips were extracted respectively and tested at a current of 20 mA. The blue shift value was a wavelength difference of 20 mA-1 mA. The specific test results are shown in Table 1.

[0095] Table 1 Performance test results of LEDs obtained in Example 10 and Comparative Example 1

[0096]

[0097]

[0098] In the test results, smaller STD values ​​and blue shift values ​​represent better consistency. From the above results, it can be seen that the light-emitting diode epitaxial wafer provided by the present invention can improve wavelength consistency and reduce wavelength blue shift.

[0099] In the description of this specification, the description with reference to the terms "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0100] The above is a preferred embodiment of the invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the invention. These improvements and modifications are also considered to be within the scope of protection of the invention.

Claims

1. A light emitting diode epitaxial wafer, characterized in that: It comprises a substrate, on which a buffer layer, a non-doped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially arranged; The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes at least one group of a first GaN layer, an AlN layer, an InN layer, and a second GaN layer that are alternately stacked in sequence.

2. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The quantum barrier layer includes 1 to 5 groups of a first GaN layer, an AlN layer, an InN layer and a second GaN layer stacked in sequence.

3. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The thickness of the quantum barrier layer is 8nm-12nm.

4. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The thickness of the first GaN layer is 0.1 nm to 5 nm.

5. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The thickness of the second GaN layer is 0.1 nm to 5 nm.

6. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The thickness of the AlN layer is 0.1 nm to 3 nm.

7. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The thickness of the InN layer is 0.1 nm to 3 nm.

8. The light emitting diode epitaxial wafer according to claim 1, characterized in that: The quantum well layer is an InGaN layer.

9. A method for preparing a light emitting diode epitaxial wafer according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. providing a substrate; S2, depositing a buffer layer, an undoped GaN layer, an N-type GaN layer, a stress release layer, a multi-quantum well layer, an electron blocking layer, and a P-type GaN layer on the substrate in sequence; The multi-quantum well layer includes quantum well layers and quantum barrier layers that are alternately stacked in sequence, and the quantum barrier layer includes at least one group of a first GaN layer, an AlN layer, an InN layer, and a second GaN layer that are alternately stacked in sequence.

10. An LED, characterized in that: The LED comprises the light emitting diode epitaxial wafer as claimed in any one of claims 1 to 8 or comprises a light emitting diode epitaxial wafer manufactured by the method for manufacturing a light emitting diode epitaxial wafer as claimed in claim 9.

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