Ultraviolet Light Emitting Diode and its Fabrication Method

Abstract

This invention discloses an ultraviolet light-emitting diode and its fabrication method. The ultraviolet light-emitting diode includes a substrate and an N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer; the P-type contact layer includes porous Al atoms sequentially stacked on the P-type semiconductor layer. x Ga (1‑x) The invention provides an ultraviolet light-emitting diode (UVLED) with an N-layer and a P-type GaN layer. While maintaining good P-type ohmic contact, it reduces in-plane total internal reflection and light absorption loss in the P-type material, thus improving the light extraction efficiency of the UVLED.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic technology, and in particular to an ultraviolet light-emitting diode and its fabrication method. Background Technology

[0002] Ultraviolet light-emitting diodes based on group III nitride semiconductor materials have a series of excellent characteristics such as small size and portability, easy integration, mercury-free and environmentally friendly, low power consumption, and rapid switching. The emission wavelength covers the long-wave ultraviolet (UVA, 315-400nm), medium-wave ultraviolet (UVB, 280-315nm) to short-wave ultraviolet (UVC, 210-280nm) bands. They have a wide range of applications in sterilization and disinfection, medical and health care, industrial catalysis, photopolymerization, non-line-of-sight communication and biochemical detection, and are regarded as an ideal choice to replace traditional ultraviolet light sources such as mercury lamps.

[0003] However, the luminous efficiency of current ultraviolet (UV) light-emitting diodes (LEDs) remains relatively low, mostly below 10%, and decreases exponentially with decreasing wavelength. One of the main reasons is the severe light absorption loss and low light extraction efficiency of p-type materials. Since AlGaN materials typically achieve p-type doping through Mg acceptor doping, and the Mg acceptor activation energy in AlGaN is relatively high and increases linearly with increasing Al content (from 150 meV in GaN to 600 meV in AlN), this high Mg acceptor activation energy makes p-type doping of AlGaN difficult, resulting in a low hole concentration. Simultaneously, the subsequent p-type ohmic contact resistance is also relatively high, leading to low luminous efficiency in UV LEDs. Because achieving efficient doping of p-AlGaN is very difficult, the p-type layer of ultraviolet light-emitting diodes usually uses p-GaN materials with higher free hole concentration and better crystal quality. However, p-GaN is not transparent to ultraviolet light and almost completely absorbs the ultraviolet light emitted from the front. Due to the absorption loss of the epitaxial layer, the light extraction efficiency of ultraviolet LEDs is low, making it even more difficult to improve the luminous efficiency of short-wavelength AlGaN-based ultraviolet LEDs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an ultraviolet light-emitting diode that, while taking into account good P-type ohmic contact, reduces in-plane total internal reflection and light absorption loss of P-type material, which is beneficial to improving the light extraction efficiency of ultraviolet light-emitting diode.

[0005] The technical problem to be solved by the present invention is to provide a method for preparing an ultraviolet light-emitting diode, which has a simple process and can stably produce the above-mentioned ultraviolet light-emitting diode with good performance.

[0006] To solve the above-mentioned technical problems, the present invention provides an ultraviolet light-emitting diode, comprising a substrate and an N-type semiconductor layer, an active region light-emitting layer, an electron blocking layer, a P-type semiconductor layer and a P-type contact layer sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer;

[0007] The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

[0008] In one embodiment, the porous Al x Ga (1-x) The density of pores in layer N is 1×10 7 / cm 2 -1×10 10 / cm 2 .

[0009] In one embodiment, the porous Al x Ga (1-x) The Mg doping concentration of the N layer is 2 × 10⁻⁶. 19 atoms / cm 3 -5×10 22 atoms / cm 3 ;

[0010] The Mg doping concentration of the P-type GaN layer is 2 × 10⁻⁶. 20 atoms / cm 3 -5×10 22 atoms / cm 3 .

[0011] In one embodiment, the porous Al x Ga (1-x) The thickness of the N layer is 0.01 μm-0.2 μm;

[0012] The thickness of the P-type GaN layer is 0.02μm-0.5μm.

[0013] In one embodiment, the P-type semiconductor layer is Al doped with Mg. y Ga (1-y) N layers, where 0.2≤y≤0.6;

[0014] The thickness of the P-type semiconductor layer is 0.01 μm-2 μm;

[0015] The Mg doping concentration of the P-type semiconductor layer is 2 × 10⁻⁶. 18 atoms / cm 3 -5×10 21 atoms / cm 3 .

[0016] In one embodiment, the N-type semiconductor layer is Al doped with Si. z Ga (1-z) N layers, where 0.4≤z≤1;

[0017] The thickness of the N-type semiconductor layer is 0.1 μm-20 μm;

[0018] The Si doping concentration of the N-type semiconductor layer is 1×10⁻⁶. 18 atoms / cm 3 -1×10 20 atoms / cm 3 .

[0019] In one embodiment, the active region light-emitting layer is an alternating layer of Al. a GaN quantum barrier layer and Al b GaN quantum well layer, where 0.5≤a≤1, 0<b<a.

[0020] In one embodiment, the electron blocking layer is an Al layer with a ladder-like decrease in Al composition. c Ga (1-c) The structure consists of N multi-layer structures, where 0.4 ≤ c ≤ 1;

[0021] The thickness of the electron blocking layer is 1nm-500nm.

[0022] To address the above problems, the present invention also provides a method for fabricating an ultraviolet light-emitting diode, comprising the following steps:

[0023] Prepare the substrate;

[0024] An N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer are sequentially deposited on the substrate.

[0025] A P-electrode is fabricated on the P-type contact layer, and an N-electrode is fabricated on the N-type semiconductor layer to obtain the finished product;

[0026] The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x)N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

[0027] In one embodiment, the P-type semiconductor layer is subjected to H2 treatment before the P-type contact layer is deposited;

[0028] The H2 treatment was carried out at a temperature of 900℃ to 1200℃ for a time of 10s to 200s.

[0029] Implementing this invention has the following beneficial effects:

[0030] The ultraviolet light-emitting diode provided by this invention includes a P-type contact layer comprising porous Al atoms sequentially stacked on the P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) The N-layer and P-type GaN layer are stacked without gaps. The ultraviolet light-emitting diode of this invention, while maintaining good P-type ohmic contact and operating voltage, minimizes the amount of GaN material in the P-type contact layer. This reduces in-plane total internal reflection in the P-type material and light absorption loss caused by the GaN material, thereby improving the light extraction efficiency of the ultraviolet light-emitting diode and ultimately increasing its luminous efficiency. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the ultraviolet light-emitting diode provided by the present invention.

[0032] Wherein: 1. Substrate; 2. N-type semiconductor layer; 3. Active light-emitting layer; 4. Electron blocking layer; 5. P-type semiconductor layer; 6. P-type contact layer; 7. N-electrode; 8. Porous Al x Ga (1-x) N-layer 61 and P-type GaN layer 62. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below.

[0034] Unless otherwise stated or in case of contradiction, the terms or phrases used herein shall have the following meanings:

[0035] In this invention, "preferred" is merely a description of a more effective implementation method or embodiment, and should be understood as not constituting a limitation on the scope of protection of this invention.

[0036] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.

[0037] In this invention, numerical ranges are involved, and unless otherwise specified, they include the two endpoints of the numerical range.

[0038] Traditional ultraviolet (UV) light-emitting diodes (LEDs) typically use P-AlGaN or P-GaN layers as the P-type layer. However, achieving efficient doping of P-AlGaN is very difficult, leading to problems such as high ohmic contact resistance. While using P-GaN materials with higher free hole concentration and better crystal quality for the P-type layer presents the problem of P-GaN's opacity to ultraviolet light, almost completely absorbing the UV light emitted from the front, resulting in low UV LED light extraction efficiency.

[0039] To address the above problems, the present invention provides an ultraviolet light-emitting diode, such as... Figure 1 As shown, it includes a substrate 1 and an N-type semiconductor layer 2, an active region light-emitting layer 3, an electron blocking layer 4, a P-type semiconductor layer 5 and a P-type contact layer 6 sequentially stacked on the substrate 1, as well as an N-electrode 7 disposed on the N-type semiconductor layer 2 and a P-electrode 8 disposed on the P-type contact layer 6.

[0040] The P-type contact layer 6 includes porous Al layers sequentially stacked on the P-type semiconductor layer. x Ga (1-x) N-layer 61 and P-type GaN layer 62, wherein x≤0.4, the porous Al x Ga (1-x) The N-layer 61 has holes, and the GaN material of the P-type GaN layer 62 fills the holes to make the porous Al x Ga (1-x) N-layer 61 and P-type GaN layer 62 are stacked without gaps.

[0041] The ultraviolet light-emitting diode of this invention, while maintaining good P-type ohmic contact and operating voltage, minimizes the amount of GaN material in the P-type contact layer. This reduces in-plane total internal reflection in the P-type material and light absorption loss caused by GaN material, thereby improving the light extraction efficiency of the ultraviolet light-emitting diode and ultimately increasing its luminous efficiency. The inventors discovered that the Al... x Ga (1-x) The presence of holes in layer N is key to achieving the aforementioned effect. In one embodiment, the Al... x Ga(1-x) The N-layer has holes of uniform size and even distribution. Preferably, the porous Al... x Ga (1-x) The density of pores on layer N, 61 is 1×10⁻⁶. 7 / cm 2 -1×10 10 / cm 2 More preferably, the porous Al x Ga (1-x) The pores in layer N61 are V-shaped pores, which are pits with a V-shaped cross-section formed by controlling the material growth conditions. In one embodiment, during the deposition of the porous Al... x Ga (1-x) Before the N-layer 61, the P-type semiconductor layer 5 undergoes H2 treatment; the H2 treatment temperature is 900℃-1200℃, and the time is 10s-200s. This specific H2 treatment etches the surface of the P-type semiconductor layer, preferentially decomposing crystals with poor crystal quality, thereby forming an uneven, rough P-type semiconductor layer surface. This makes the subsequently deposited porous Al... x Ga (1-x) Layer N 61 can be deposited on uneven surfaces, which is beneficial to the porous Al x Ga (1-x) The formation of V-pits in layer N, 61.

[0042] In addition, in one embodiment, the porous Al x Ga (1-x) The Mg doping concentration of N-layer 61 is 2 × 10⁻⁶. 19 atoms / cm 3 -5×10 22 atoms / cm 3 The porous Al x Ga (1-x) The thickness of the N-layer 61 is 0.01 μm-0.2 μm; the Mg doping concentration of the P-type GaN layer 62 is 2 × 10⁻⁶. 20 atoms / cm 3 -5×10 22 atoms / cm 3 The thickness of the P-type GaN layer 62 is 0.02μm-0.5μm.

[0043] In one embodiment, the P-type semiconductor layer 5 is Al doped with Mg. y Ga (1-y) The N-layer has a density of 0.2 ≤ y ≤ 0.6; the thickness of the P-type semiconductor layer 5 is 0.01 μm-2 μm; and the Mg doping concentration of the P-type semiconductor layer 5 is 2 × 10⁻⁶. 18atoms / cm 3 -5×10 21 atoms / cm 3 .

[0044] In one embodiment, the N-type semiconductor layer 2 is Al doped with Si. z Ga (1-z) The N-type semiconductor layer 2 has an N-layer structure, where 0.4 ≤ z ≤ 1; the thickness of the N-type semiconductor layer 2 is 0.1 μm-20 μm; and the Si doping concentration of the N-type semiconductor layer 2 is 1 × 10⁻⁶. 18 atoms / cm 3 -1×10 20 atoms / cm 3 .

[0045] In one embodiment, the active region light-emitting layer 3 is an alternating layer of Al. a GaN quantum barrier layer and Al b GaN quantum well layer, where 0.5≤a≤1, 0<b<a.

[0046] In one embodiment, the electron blocking layer 4 is an Al composition with a ladder-like decrease in Al content. c Ga (1-c) The structure consists of N multilayers, where 0.4 ≤ c ≤ 1; the thickness of the electron blocking layer 4 is 1 nm-500 nm.

[0047] Accordingly, the present invention provides a method for fabricating an ultraviolet light-emitting diode, comprising the following steps:

[0048] Prepare substrate 1;

[0049] An N-type semiconductor layer 3, an active light-emitting layer 3, an electron blocking layer 4, a P-type semiconductor layer 5, and a P-type contact layer 6 are sequentially deposited on the substrate 1.

[0050] A P-electrode 8 is fabricated on the P-type contact layer 6, and an N-electrode 7 is fabricated on the N-type semiconductor layer 2 to obtain the finished product;

[0051] The P-type contact layer 6 includes porous Al atoms sequentially stacked on the P-type semiconductor layer 5. x Ga (1-x) N-layer 61 and P-type GaN layer 62, wherein x≤0.4, the porous Al x Ga (1-x) The N-layer 61 has holes, and the GaN material of the P-type GaN layer 62 fills the holes to make the porous Al x Ga (1-x) N-layer 61 and P-type GaN layer 62 are stacked without gaps.

[0052] In one embodiment, before depositing the P-type contact layer 6, the P-type semiconductor layer 5 is subjected to H2 treatment; the H2 treatment temperature is 900℃-1200℃, and the time is 10s-200s. The surface of the P-type semiconductor layer after the above H2 treatment forms an uneven, roughened surface, which can reduce in-plane total reflection of the P-type material. Simultaneously, H2 treatment of the P-type semiconductor layer 5 is also more conducive to porous Al. x Ga (1-x) A V-shaped pit is formed in layer N, 61.

[0053] In one embodiment, the step of fabricating a P-electrode 8 on the P-type contact layer 6 and an N-electrode 7 on the N-type semiconductor layer 2 includes the following steps:

[0054] Dry etching was used to etch the P-type contact layer 6, with the etching depth extending from the surface to the middle of the N-type semiconductor layer 2.

[0055] A P-electrode 8 is formed by depositing metal on the unetched P-type contact layer 6 using a metal sputtering method, and an N-electrode 7 is formed by depositing metal on the etched N-type semiconductor layer 2 using a metal sputtering method.

[0056] The above preparation process is completed using MOCVD equipment, CVD equipment or PVD equipment, and the present invention does not make specific limitations.

[0057] The present invention is further illustrated below with specific embodiments:

[0058] Example 1

[0059] This embodiment provides an ultraviolet light-emitting diode, including a substrate and an N-type semiconductor layer, an active region light-emitting layer, an electron blocking layer, a P-type semiconductor layer, a P-type contact layer, an N-electrode, and a P-electrode sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer;

[0060] The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x is 0.2, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

[0061] The Al x Ga (1-x) The Mg doping concentration of the N-layer is 1×10⁻⁶. 20 atoms / cm 3The thickness is 0.1μm.

[0062] The Mg doping concentration of the P-type GaN layer is 1×10⁻⁶. 21 atoms / cm 3 The thickness is 0.3μm.

[0063] The P-type semiconductor layer is Al doped with Mg. y Ga (1-y) The N-layer has a y-value of 0.4, and the thickness of the P-type semiconductor layer is 1 μm with a Mg doping concentration of 1 × 10⁻⁴. 19 atoms / cm 3 .

[0064] The above-mentioned method for fabricating an ultraviolet light-emitting diode includes the following steps:

[0065] Prepare the substrate;

[0066] An N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer are sequentially deposited on the substrate.

[0067] A P-electrode is fabricated on the P-type contact layer, and an N-electrode is fabricated on the N-type semiconductor layer to obtain the finished product;

[0068] Before depositing the P-type contact layer, the P-type semiconductor layer is subjected to H2 treatment; the H2 treatment temperature is 1100℃ and the time is 60s.

[0069] Example 2

[0070] This embodiment provides an ultraviolet light-emitting diode, including a substrate and an N-type semiconductor layer, an active region light-emitting layer, an electron blocking layer, a P-type semiconductor layer, a P-type contact layer, an N-electrode, and a P-electrode sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer;

[0071] The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x is 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

[0072] The Al x Ga (1-x) The Mg doping concentration of the N layer is 2 × 10⁻⁶. 19atoms / cm 3 The thickness is 0.18μm.

[0073] The Mg doping concentration of the P-type GaN layer is 5 × 10⁻⁶. 20 atoms / cm 3 The thickness is 0.45μm.

[0074] The P-type semiconductor layer is Al doped with Mg. y Ga (1-y) The N-layer has a y-value of 0.4, and the thickness of the P-type semiconductor layer is 1 μm with a Mg doping concentration of 1 × 10⁻⁴. 19 atoms / cm 3 .

[0075] The above-mentioned method for fabricating an ultraviolet light-emitting diode includes the following steps:

[0076] Prepare the substrate;

[0077] An N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer are sequentially deposited on the substrate.

[0078] A P-electrode is fabricated on the P-type contact layer, and an N-electrode is fabricated on the N-type semiconductor layer to obtain the finished product;

[0079] Before depositing the P-type contact layer, the P-type semiconductor layer is subjected to H2 treatment; the H2 treatment temperature is 1200℃ and the time is 30s.

[0080] Example 3

[0081] This embodiment provides an ultraviolet light-emitting diode, including a substrate and an N-type semiconductor layer, an active region light-emitting layer, an electron blocking layer, a P-type semiconductor layer, a P-type contact layer, an N-electrode, and a P-electrode sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer;

[0082] The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x is 0.1, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

[0083] The Al x Ga (1-x)The Mg doping concentration of the N-layer is 1×10⁻⁶. 22 atoms / cm 3 The thickness is 0.1μm.

[0084] The Mg doping concentration of the P-type GaN layer is 5 × 10⁻⁶. 22 atoms / cm 3 The thickness is 0.3μm.

[0085] The P-type semiconductor layer is Al doped with Mg. y Ga (1-y) The N-layer has a y-value of 0.4, and the thickness of the P-type semiconductor layer is 1 μm with a Mg doping concentration of 1 × 10⁻⁴. 19 atoms / cm 3 .

[0086] The above-mentioned method for fabricating an ultraviolet light-emitting diode includes the following steps:

[0087] Prepare the substrate;

[0088] An N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer are sequentially deposited on the substrate.

[0089] A P-electrode is fabricated on the P-type contact layer, and an N-electrode is fabricated on the N-type semiconductor layer to obtain the finished product;

[0090] Before depositing the P-type contact layer, the P-type semiconductor layer is subjected to H2 treatment; the H2 treatment temperature is 900°C and the time is 180s.

[0091] Example 4

[0092] This embodiment provides an ultraviolet light-emitting diode, which differs from Embodiment 1 in that the P-type semiconductor layer is not subjected to H2 treatment before depositing the P-type contact layer. All other aspects are the same as in Embodiment 1.

[0093] Comparative Example 1

[0094] This comparative example provides an ultraviolet light-emitting diode, which differs from Example 1 in that: the P-type contact layer includes Al atoms sequentially stacked on the P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, where x is 0.2, the Al x Ga (1-x) There are no holes on layer N. Everything else is the same as in Example 1.

[0095] The ultraviolet light-emitting diodes prepared in Examples 1-4 and Comparative Example 1 were tested. The specific test results are shown in Table 1.

[0096] Table 1. Performance test results of the ultraviolet light-emitting diodes prepared in Examples 1-4 and Comparative Example 1

[0097]

[0098]

[0099] As can be seen from the above results, the ultraviolet light-emitting diode provided by the present invention includes a P-type contact layer comprising porous Al atoms sequentially stacked on the P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) The N-layer and P-type GaN layer are stacked without gaps. The ultraviolet light-emitting diode of this invention, while maintaining good P-type ohmic contact and operating voltage, minimizes the amount of GaN material in the P-type contact layer. This reduces in-plane total internal reflection in the P-type material and light absorption loss caused by the GaN material, thereby improving the light extraction efficiency of the ultraviolet light-emitting diode and ultimately increasing its luminous efficiency.

[0100] The above description is a preferred embodiment of the invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the invention, and these improvements and modifications are also considered to be within the scope of protection of the invention.

Claims

1. An ultraviolet light-emitting diode, characterized in that, It includes a substrate and an N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer and a P-type contact layer sequentially stacked on the substrate, as well as an N-electrode disposed on the N-type semiconductor layer and a P-electrode disposed on the P-type contact layer; The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

2. The ultraviolet light-emitting diode as described in claim 1, characterized in that, The porous Al x Ga (1-x) The density of pores in layer N is 1×10 7 / cm 2 -1×10 10 / cm 2 .

3. The ultraviolet light-emitting diode as described in claim 1, characterized in that, The porous Al x Ga (1-x) The Mg doping concentration of the N layer is 2 × 10⁻⁶. 19 atoms / cm 3 -5×10 22 atoms / cm 3 ; The Mg doping concentration of the P-type GaN layer is 2 × 10⁻⁶. 20 atoms / cm 3 -5×10 22 atoms / cm 3 .

4. The ultraviolet light-emitting diode as described in claim 1, characterized in that, The porous Al x Ga (1-x) The thickness of the N layer is 0.01 μm-0.2 μm; The thickness of the P-type GaN layer is 0.02μm-0.5μm.

5. The ultraviolet light-emitting diode according to any one of claims 1 to 4, characterized in that, The P-type semiconductor layer is Al doped with Mg. y Ga (1-y) N layers, where 0.2≤y≤0.6; The thickness of the P-type semiconductor layer is 0.01 μm-2 μm; The Mg doping concentration of the P-type semiconductor layer is 2 × 10⁻⁶. 18 atoms / cm 3 -5×10 21 atoms / cm 3 .

6. The ultraviolet light-emitting diode according to any one of claims 1 to 4, characterized in that, The N-type semiconductor layer is Al doped with Si. z Ga (1-z) N layers, where 0.4≤z≤1; The thickness of the N-type semiconductor layer is 0.1 μm-20 μm; The Si doping concentration of the N-type semiconductor layer is 1×10⁻⁶. 18 atoms / cm 3 -1×10 20 atoms / cm 3 .

7. The ultraviolet light-emitting diode according to any one of claims 1 to 4, characterized in that, The active region light-emitting layer is composed of alternating Al atoms. a GaN quantum barrier layer and Al b GaN quantum well layer, where 0.5≤a≤1, 0<b<a.

8. The ultraviolet light-emitting diode according to any one of claims 1 to 4, characterized in that, The electron blocking layer is an Al composition with a trapezoidal decrease in Al content. c Ga (1-c) The structure consists of N multi-layer structures, where 0.4 ≤ c ≤ 1; The thickness of the electron blocking layer is 1nm-500nm.

9. A method for fabricating an ultraviolet light-emitting diode as described in any one of claims 1-8, characterized in that, Includes the following steps: Prepare the substrate; An N-type semiconductor layer, an active light-emitting layer, an electron blocking layer, a P-type semiconductor layer, and a P-type contact layer are sequentially deposited on the substrate. A P-electrode is fabricated on the P-type contact layer, and an N-electrode is fabricated on the N-type semiconductor layer to obtain the finished product; The P-type contact layer includes porous Al atoms sequentially stacked on a P-type semiconductor layer. x Ga (1-x) N-type and P-type GaN layers, wherein x ≤ 0.4, the porous Al x Ga (1-x) The N-layer has holes, and the GaN material of the P-type GaN layer fills the holes to make the porous Al x Ga (1-x) N-type and P-type GaN layers are stacked without gaps.

10. The method for fabricating an ultraviolet light-emitting diode as described in claim 9, characterized in that, Before depositing the P-type contact layer, the P-type semiconductor layer is subjected to H2 treatment; The H2 treatment was carried out at a temperature of 900℃ to 1200℃ for a time of 10s to 200s.

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