Light emitting diode and preparation method thereof

Abstract

The invention discloses a light emitting diode and a preparation method thereof, and belongs to the technical field of semiconductors. The light emitting diode comprises a first semiconductor layer, a second semiconductor layer and a multi-quantum well layer located between the first semiconductor layer and the second semiconductor layer. The first semiconductor layer comprises a plurality of N-type doped Al < x > Ga < 1-x > N layers and C-doped Al < y > Ga < 1-y > N layers which are periodically and alternately stacked, x is less than or equal to 1, 0lt; y < = 1.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of semiconductor technology, and in particular, to a light emitting diode and a preparation method thereof. BACKGROUND

[0002] A light emitting diode is a kind of semiconductor electronic component capable of emitting light, which is widely used in lighting, display and other fields.

[0003] In the related art, a light emitting diode includes a first semiconductor layer, a multi-quantum well layer and a second semiconductor layer which are sequentially stacked.

[0004] How to improve the above-mentioned light emitting diode structure and improve the light emitting efficiency of the light emitting diode is the focus of current research. SUMMARY

[0005] Embodiments of the present disclosure provide a light emitting diode and a preparation method thereof, which can improve the light emitting efficiency of the light emitting diode. The technical solutions are as follows: In one aspect, the present disclosure provides a light emitting diode, which includes a first semiconductor layer, a second semiconductor layer and a multi-quantum well layer between the first semiconductor layer and the second semiconductor layer. The first semiconductor layer includes a plurality of periodically and alternately stacked N-type doped Al x Ga (1-x) N layers and C-doped Al y Ga (1-y) N layers. Wherein, 0 < x ≤ 1, 0 < y ≤ 1.

[0006] Optionally, along the direction from the first semiconductor layer to the second semiconductor layer, the doping concentration of C in the plurality of C-doped Al y Ga (1-y) N layers gradually decreases.

[0007] Optionally, along the direction from the first semiconductor layer to the second semiconductor layer, the thickness of the plurality of C-doped Al y Ga (1-y) N layers gradually decreases.

[0008] Optionally, the first semiconductor layer includes three periodically and alternately stacked N-type doped Al x Ga (1-x) N layers and C-doped Al y Ga (1-y) N layers.

[0009] Optionally, along the direction from the first semiconductor layer to the second semiconductor layer, the doping concentration of C in the plurality of C-doped Al y Ga (1-y)The doping concentration of C in the N layers is 1×10 18 2×10 18 cm -3 , 5×10 17 1×10 18 cm -3 , 1×10 17 5×10 17 cm -3 .

[0010] Optionally, the thicknesses of the plurality of C-doped Al y Ga (1-y) N layers are 150-200 nm, 100-150 nm, and 50-100 nm, respectively, along a direction from the first semiconductor layer to the second semiconductor layer.

[0011] Optionally, the plurality of N-type doped Al x Ga (1-x) N layers are Si-doped GaN layers.

[0012] Optionally, the doping concentration of Si in the plurality of N-type doped Al x Ga (1-x) N layers is the same, and the thicknesses of the plurality of N-type doped Al x Ga (1-x) N layers are the same.

[0013] Optionally, the doping concentration of Si in the N-type doped Al x Ga (1-x) N layer is 1×10 19 1×10 21 cm -3 .

[0014] Optionally, the thickness of the N-type doped Al x Ga (1-x) N layer is 0.5-1 μm.

[0015] In another aspect, a preparation method of a light emitting diode is provided, the preparation method comprising: growing a first semiconductor layer, the first semiconductor layer comprising a plurality of periodically and alternately stacked N-type doped Al x Ga (1-x) N layers and C-doped Al y Ga (1-y) N layers, wherein 0 growing a multi-quantum well layer on the first semiconductor layer; growing the second semiconductor layer on the multi-quantum well layer.

[0016] The beneficial effects of the technical solutions provided in this disclosure are: In this embodiment of the disclosure, in N-type doped Al x Ga (1-x) Multiple C-doped Al atoms were inserted in the middle of the N-layer. y Ga (1-y) N-layer, due to C doping with Al y Ga (1-y) The relatively high band barrier of the N-layer improves the lateral current spread of the LED, allowing current to flow through more paths, which is equivalent to a multi-parallel circuit, thus reducing the overall parasitic resistance. C-doped Al y Ga (1-y) The N-layer, as the current spreading layer of the LED, can improve the uniformity of the current distribution, reduce the operating voltage of the LED, increase the luminous efficiency, enhance the external quantum efficiency, and reduce the reverse leakage current, thereby improving the photoelectric performance of the LED. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure; Figure 2 This is a schematic diagram of the structure of a first semiconductor layer provided in an embodiment of this disclosure; Figure 3 This is a schematic diagram of another light-emitting diode structure provided in an embodiment of this disclosure; Figure 4 This is a flowchart of a method for fabricating a light-emitting diode provided in an embodiment of this disclosure; Figure 5 This is a flowchart of another method for fabricating a light-emitting diode provided in this embodiment.

[0019] The attached figures are labeled as follows: 100: Substrate; 101: First semiconductor layer; 102: Active layer; 103: Second semiconductor layer; 104: Buffer layer; 105: Undoped GaN layer; 106: Electron blocking layer; 107: Contact layer; 111: N-type doped Al x Ga (1-x) N-layer; 112: C-doped Al y Ga (1-y) N layers. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0021] This disclosure provides an epitaxial structure and its fabrication method for enhancing the current spread capability of a light-emitting diode (LED). The purpose is to enhance the lateral current spread capability, reduce the stress during the growth of multiple quantum well layers, improve the crystal quality and current injection uniformity of the grown multiple quantum well layers, thereby improving the overall optoelectronic performance of the LED.

[0022] Figure 1 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure, with reference to... Figure 1 As can be seen, the present disclosure provides a light-emitting diode, which includes a first semiconductor layer 101, a multiple quantum well layer 102 and a second semiconductor layer 103 stacked sequentially.

[0023] Figure 2 This is a schematic diagram of the structure of a first semiconductor layer provided in an embodiment of this disclosure. See also... Figure 2 The first semiconductor layer 101 includes multiple N-type doped Al layers stacked alternately in a periodic manner. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) Nth floor 112.

[0024] Among them, 0 <x≤1,0<y≤1。

[0025] It should be noted that the first semiconductor layer 101 needs to be connected to the first electrode, and the second semiconductor layer 103 needs to be connected to the second electrode, with current flowing between the first and second electrodes. One of the first and second electrodes is an N-electrode, and the other is a P-electrode.

[0026] In this embodiment of the disclosure, in N-type doped Al x Ga (1-x) Multiple C-doped Al atoms were inserted in the middle of the N-layer. y Ga (1-y) N-layer, due to C doping with Al y Ga (1-y) The relatively high band barrier of the N-layer improves the lateral current spread of the LED, allowing current to flow through more paths, which is equivalent to a multi-parallel circuit, thus reducing the overall parasitic resistance. C-doped Al y Ga (1-y)The N-layer, as the current spreading layer of the LED, can improve the uniformity of the current distribution, reduce the operating voltage of the LED, increase the luminous efficiency, enhance the external quantum efficiency, and reduce the reverse leakage current, thereby improving the photoelectric performance of the LED.

[0027] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) In the N-layer 112, the C doping concentration gradually decreases.

[0028] C substitutes for N sites in the AlGaN layer, thereby generating acceptor CN, in N-type doped Al x Ga (1-x) C-doped Al was introduced in the middle of the N-layer. y Ga (1-y) The N-layer forms a PN junction, raising the energy band barrier. As charge carriers overcome this barrier, a secondary distribution occurs, leading to current expansion. However, excessively high carbon doping concentration in the AlGaN layer can actually decrease the luminous efficiency of the LED due to the introduced barrier. Therefore, a doping method with gradually decreasing carbon doping concentration is employed. The AlGaN layer near the multiple quantum well layer has a low carbon doping concentration to ensure effective carrier transport, while the AlGaN layer further away from the multiple quantum well layer has a high carbon doping concentration to improve the efficiency of N-type doped AlGaN. x Ga (1-x) The carriers in the N-layer are effectively expanded, thereby improving the photoelectric performance of the light-emitting diode.

[0029] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The thickness of the N-layer 112 gradually decreases.

[0030] In this implementation, C-doped Al is used. y Ga (1-y) The doping pattern of gradually decreasing thickness of the N-layer 112 involves a low C doping concentration and small thickness in the AlGaN layer near the multi-quantum-well layer, ensuring effective carrier transport, while a high C doping concentration and large thickness in the AlGaN layer further away from the multi-quantum-well layer, which is beneficial for N-type doped AlGaN. x Ga (1-x) The carriers in the N-layer are effectively expanded.

[0031] In this embodiment of the disclosure, the first semiconductor layer 101 comprises 3 to 5 alternating layers of N-type doped Al. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) Nth floor 112.

[0032] For example, the first semiconductor layer 101 includes three periodically alternating layers of N-type doped Al. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) Nth floor 112.

[0033] In this implementation, three alternating layers of N-type doped Al are used. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) N-layer 112, as the first semiconductor layer, can not only be used to insert three C-doped Al atoms... y Ga (1-y) The N-layer significantly improves the photoelectric performance of the light-emitting diode, and is not affected by the inserted C-doped Al. y Ga (1-y) Too many N layers cause problems such as excessive manufacturing complexity and excessive overall thickness.

[0034] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The C doping concentration in the N-layer 112 is 1×10⁻⁶. 18 ~2×10 18 cm -3 5×10 17 ~1×10 18 cm -3 1×10 17 ~5×10 17 cm -3 .

[0035] In this implementation, three C atoms are doped with Al y Ga (1-y) The N-layer 112 uses the above-mentioned doping concentration, which can ensure both effective carrier transport and effective carrier expansion.

[0036] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The thicknesses of the N-layer 112 are 150~200nm, 100~150nm, and 50~100nm, respectively.

[0037] In this implementation, three C atoms are doped with Al y Ga (1-y)The N-layer 112 uses the aforementioned thickness, which ensures that each C-doped Al y Ga (1-y) The N-layer serves a purpose without making the overall thickness of the first semiconductor layer too large.

[0038] In some examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) In the N-layer 112, the C doping concentration can decrease at equal or proportional rates.

[0039] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, the three C-doped Al atoms y Ga (1-y) The C doping concentration in the N-layer 112 is 1.5 × 10⁻⁶. 18 cm -3 1×10 18 cm -3 5×10 17 cm -3 .

[0040] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, the three C-doped Al atoms y Ga (1-y) The C doping concentration in the N-layer 112 is 2×10⁻⁶. 18 cm -3 1×10 18 cm -3 5×10 17 cm -3 .

[0041] In other examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) The doping concentration of C in the N-layer 112 can decrease in an irregular manner.

[0042] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The C doping concentration in the N-layer 112 is 1.5 × 10⁻⁶. 18 cm -3 7.5×10 17 3×10 17 cm -3 .

[0043] In some examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y)The thickness of layer N112 can decrease at equal or proportional rates.

[0044] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 150nm, 100nm, and 50nm, respectively.

[0045] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 200nm, 100nm, and 50nm, respectively.

[0046] In other examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) The thickness of the N-layer 112 can decrease in an irregular manner.

[0047] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 180nm, 120nm, and 80nm, respectively.

[0048] In this embodiment of the disclosure, a plurality of the N-type doped Al x Ga (1-x) The N-layer 111 is a Si-doped GaN layer.

[0049] Multiple N-type doped Al x Ga (1-x) The Si doping concentration is the same in the N-layer 111, and multiple N-type doped Al atoms... x Ga (1-x) The thickness of layer N is the same as that of layer 111.

[0050] In this implementation, multiple N-type doped Al x Ga (1-x) In the N-layer, the Si doping concentration and thickness are the same, which facilitates the doping of multiple N-type Al layers. x Ga (1-x) The creation of layer N.

[0051] In this embodiment of the disclosure, the N-type doped Al x Ga (1-x) The Si doping concentration in the N-layer 111 is 1×10⁻⁶. 19 ~1×10 21 cm -3 .

[0052] For example, the N-type doped Al x Ga (1-x) The Si doping concentration in the N-layer 111 is 1×10⁻⁶. 20 cm -3 .

[0053] In this implementation, the doping concentration of Si described above ensures the carrier concentration provided by the first semiconductor layer.

[0054] In this embodiment of the disclosure, the N-type doped Al x Ga (1-x) The thickness of the N-layer 111 is 0.5~1μm.

[0055] For example, the N-type doped Al x Ga (1-x) The thickness of the N-layer 111 is 0.8 μm.

[0056] In this implementation, N-type doped Al with the aforementioned thickness is used. x Ga (1-x) The N-layer ensures the carrier concentration provided by the first semiconductor layer.

[0057] In this embodiment of the disclosure, the multiple quantum well layer 102 can be a superlattice structure composed of a quantum well layer and a quantum barrier layer.

[0058] The quantum well layer can be an InGaN quantum well layer, and the quantum barrier layer can be a GaN quantum barrier layer.

[0059] In the embodiments disclosed herein, the thickness of the InGaN quantum well layer is 2-4 nm, the In content in the InGaN well layer is 0.1-0.4, and the thickness of the GaN quantum barrier layer is 5-15 nm.

[0060] For example, the InGaN quantum well layer has a thickness of 3 nm, the In content in the InGaN well layer is 0.2, and the GaN quantum barrier layer has a thickness of 10 nm.

[0061] In this embodiment of the disclosure, the multi-quantum well layer 102 may include 5 to 15 cycles.

[0062] For example, the multi-quantum well layer 102 may include 10 cycles.

[0063] In this embodiment of the disclosure, the second semiconductor layer 103 is a P-type layer.

[0064] For example, the second semiconductor layer 103 is a P-type GaN layer.

[0065] In this embodiment of the disclosure, the doping element of the second semiconductor layer 103 can be Mg, and the doping concentration of Mg can be 1×10⁻⁶. 19 ~5×10 21 cm -3 .

[0066] For example, the thickness of the second semiconductor layer 103 can be 30~100nm.

[0067] For example, the thickness of the second semiconductor layer 103 is 50 nm.

[0068] Figure 3 This is a schematic diagram of another light-emitting diode structure provided in this disclosure embodiment, see below. Figure 3 The light-emitting diode may also include a substrate 100, on which a first semiconductor layer 101 is located.

[0069] For example, the substrate 100 may be a sapphire substrate 100.

[0070] See Figure 3 The light-emitting diode may also include a buffer layer 104 and an undoped GaN layer 105, the buffer layer 104 and the undoped GaN layer 105 being stacked on the substrate 100, and the first semiconductor layer 101 being located on the undoped GaN layer 105.

[0071] For example, buffer layer 104 can be an AlN buffer layer.

[0072] For example, the thickness of the buffer layer 104 can be 15~30nm.

[0073] For example, the thickness of the buffer layer 104 is 20 nm.

[0074] For example, the thickness of the undoped GaN layer 105 can be 1~3µm.

[0075] For example, the thickness of the undoped GaN layer 105 is 2µm.

[0076] See Figure 3 The light-emitting diode may also include an electron blocking layer 106, which is located between the multiple quantum well layer 102 and the second semiconductor layer 103.

[0077] For example, the electron blocking layer 106 can be an AlGaN electron blocking layer.

[0078] For example, the thickness of the electron blocking layer 106 can be 50~100nm.

[0079] For example, the electron blocking layer 106 has a thickness of 80 nm.

[0080] SeeFigure 3 The light-emitting diode may also include a contact layer 107, which is located on the second semiconductor layer 103.

[0081] For example, the contact layer 107 may be a GaN layer with the same doping as the second semiconductor layer 103, such as a P-type GaN contact layer.

[0082] For example, the thickness of the contact layer 107 can be 10~30nm.

[0083] For example, the thickness of the contact layer 107 is 20 nm.

[0084] Alternatively, the light-emitting diode may include more or fewer film layers.

[0085] For example, the light-emitting diode may further include a low-temperature GaN layer located between the first semiconductor layer and the multiple quantum well layer. The low-temperature GaN layer may also adopt an improved version of the first semiconductor layer of the present disclosure, that is, inserting multiple C-doped Al atoms therein. y Ga (1-y) N layers.

[0086] Figure 4 This is a flowchart of a method for fabricating a light-emitting diode according to an embodiment of this disclosure, with reference to... Figure 4 As can be seen, this disclosure provides a method for fabricating a light-emitting diode, the method comprising: S101: Grow a first semiconductor layer, the first semiconductor layer comprising multiple periodically alternating N-type doped Al layers. x Ga (1-x) N-layer and C-doped Al y Ga (1-y) N layers.

[0087] Among them, 0 <x≤1,0<y≤1。

[0088] S102: Grow a multi-quantum-well layer on the first semiconductor layer.

[0089] S103: Grow the second semiconductor layer on the multi-quantum-well layer.

[0090] In this embodiment of the disclosure, in N-type doped Al x Ga (1-x) Multiple C-doped Al atoms were inserted in the middle of the N-layer. y Ga (1-y) N-layer, due to C doping with Al y Ga (1-y) The relatively high band barrier of the N-layer improves the lateral current spread of the LED, allowing current to flow through more paths, which is equivalent to a multi-parallel circuit, thus reducing the overall parasitic resistance. C-doped Aly Ga (1-y) The N-layer, as the current spreading layer of the LED, can improve the uniformity of the current distribution, reduce the operating voltage of the LED, increase the luminous efficiency, enhance the external quantum efficiency, and reduce the reverse leakage current, thereby improving the photoelectric performance of the LED.

[0091] Figure 5 This is a flowchart of another method for fabricating a light-emitting diode provided in this disclosure embodiment, see reference. Figure 5 It can be seen that the method for fabricating this light-emitting diode includes: S201: Provide a substrate.

[0092] The substrate can be a sapphire substrate, for example, (0001) crystal orientation sapphire (Al2O3) as the substrate.

[0093] Optionally, step S201 may further include: placing the sapphire substrate in a graphite disk in an epitaxial vapor deposition reaction chamber, and treating the surface of the substrate for epitaxial layer growth for 2-30 minutes under a hydrogen atmosphere.

[0094] S202: Growing a buffer layer on the substrate.

[0095] The buffer layer can be an AlN buffer layer.

[0096] In this embodiment of the disclosure, an AlN buffer layer can be grown using a physical vapor deposition (PVD) apparatus with a sputtering power of 2500~4000W, for example 3000W.

[0097] For example, an AlN buffer layer of 15-30 nm is grown in an environment with a growth temperature of 500-650 °C and a growth pressure of 1-10 torr.

[0098] For example, a 20 nm AlN buffer layer was grown at a growth temperature of 600 °C and a growth pressure of 5 torr.

[0099] Optionally, after growth is complete, the substrate is transferred to a metal-organic chemical vapor deposition (MOCVD) apparatus for in-situ annealing under a hydrogen atmosphere. The annealing temperature is 1000~1200℃, the chamber pressure is 150~500 Torr, and the annealing time is 5~10 minutes.

[0100] For example, the annealing temperature is 1100℃, the cavity pressure is 300 Torr, and the annealing time is 8 minutes.

[0101] After annealing, subsequent semiconductor films are grown in an MOCVD device.

[0102] S203: An undoped GaN layer is grown on the buffer layer.

[0103] In this embodiment of the disclosure, after annealing, an NH3 and TMGa source are introduced to grow an undoped GaN layer.

[0104] For example, an undoped GaN layer of 1-3 μm is grown at a growth temperature of 1050-1200°C and a growth pressure of 100-300 Torr.

[0105] For example, a 2 μm undoped GaN layer was grown at a growth temperature of 1100 °C and a growth pressure of 200 Torr.

[0106] S204: The first semiconductor layer is grown on an undoped GaN layer.

[0107] The first semiconductor layer 101 includes multiple N-type doped Al layers stacked alternately in a periodic manner. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) N-layer 112, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, contains a plurality of C-doped Al atoms. y Ga (1-y) In the N-layer 112, the C doping concentration gradually decreases.

[0108] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The thickness of the N-layer 112 gradually decreases.

[0109] In this implementation, C-doped Al is used. y Ga (1-y) The doping pattern of gradually decreasing thickness of the N-layer 112 involves a low C doping concentration and small thickness in the AlGaN layer near the multi-quantum-well layer, ensuring effective carrier transport, while a high C doping concentration and large thickness in the AlGaN layer further away from the multi-quantum-well layer, which is beneficial for N-type doped AlGaN. x Ga (1-x) The carriers in the N-layer are effectively expanded.

[0110] In this embodiment of the disclosure, the first semiconductor layer 101 comprises 3 to 5 alternating layers of N-type doped Al. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y)Nth floor 112.

[0111] For example, the first semiconductor layer 101 includes three periodically alternating layers of N-type doped Al. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) Nth floor 112.

[0112] In this implementation, three alternating layers of N-type doped Al are used. x Ga (1-x) N-layer 111 and C-doped Al y Ga (1-y) N-layer 112, as the first semiconductor layer, can not only be used to insert three C-doped Al atoms... y Ga (1-y) The N-layer significantly improves the photoelectric performance of the light-emitting diode, and is not affected by the inserted C-doped Al. y Ga (1-y) Too many N layers cause problems such as excessive manufacturing complexity and excessive overall thickness.

[0113] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The C doping concentration in the N-layer 112 is 1×10⁻⁶. 18 ~2×10 18 cm -3 5×10 17 ~1×10 18 cm -3 1×10 17 ~5×10 17 cm -3 .

[0114] In this implementation, three C atoms are doped with Al y Ga (1-y) The N-layer 112 uses the above-mentioned doping concentration, which can ensure both effective carrier transport and effective carrier expansion.

[0115] In this embodiment of the disclosure, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al atoms are formed. y Ga (1-y) The thicknesses of the N-layer 112 are 150~200nm, 100~150nm, and 50~100nm, respectively.

[0116] In this implementation, three C atoms are doped with Al y Ga (1-y)The N-layer 112 uses the aforementioned thickness, which ensures that each C-doped Al y Ga (1-y) The N-layer serves a purpose without making the overall thickness of the first semiconductor layer too large.

[0117] In some examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) In the N-layer 112, the C doping concentration can decrease at equal or proportional rates.

[0118] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, the three C-doped Al atoms y Ga (1-y) The C doping concentration in the N-layer 112 is 1.5 × 10⁻⁶. 18 cm -3 1×10 18 cm -3 5×10 17 cm -3 .

[0119] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, the three C-doped Al atoms y Ga (1-y) The C doping concentration in the N-layer 112 is 2×10⁻⁶. 18 cm -3 1×10 18 cm -3 5×10 17 cm -3 .

[0120] In other examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) The doping concentration of C in the N-layer 112 can decrease in an irregular manner.

[0121] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The C doping concentration in the N-layer 112 is 1.5 × 10⁻⁶. 18 cm -3 7.5×10 17 3×10 17 cm -3 .

[0122] In some examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y)The thickness of layer N112 can decrease at equal or proportional rates.

[0123] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 150nm, 100nm, and 50nm, respectively.

[0124] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 200nm, 100nm, and 50nm, respectively.

[0125] In other examples of embodiments of this disclosure, a plurality of the C-doped Al y Ga (1-y) The thickness of the N-layer 112 can decrease in an irregular manner.

[0126] For example, along the direction from the first semiconductor layer 101 to the second semiconductor layer 103, a plurality of C-doped Al y Ga (1-y) The thicknesses of the N-layer 112 are 180nm, 120nm, and 80nm, respectively.

[0127] In this embodiment of the disclosure, a plurality of the N-type doped Al x Ga (1-x) The N-layer 111 is a Si-doped GaN layer.

[0128] Multiple N-type doped Al x Ga (1-x) The Si doping concentration is the same in the N-layer 111, and multiple N-type doped Al atoms... x Ga (1-x) The thickness of layer N is the same as that of layer 111.

[0129] In this implementation, multiple N-type doped Al x Ga (1-x) In the N-layer, the Si doping concentration and thickness are the same, which facilitates the doping of multiple N-type Al layers. x Ga (1-x) The creation of layer N.

[0130] In this embodiment of the disclosure, the N-type doped Al x Ga (1-x) The Si doping concentration in the N-layer 111 is 1×10⁻⁶. 19 ~1×10 21 cm -3 .

[0131] For example, the N-type doped Al x Ga (1-x) The Si doping concentration in the N-layer 111 is 1×10⁻⁶. 20 cm -3 .

[0132] In this implementation, the doping concentration of Si described above ensures the carrier concentration provided by the first semiconductor layer.

[0133] In this embodiment of the disclosure, the N-type doped Al x Ga (1-x) The thickness of the N-layer 111 is 0.5~1μm.

[0134] For example, the N-type doped Al x Ga (1-x) The thickness of the N-layer 111 is 0.8 μm.

[0135] In this implementation, N-type doped Al with the aforementioned thickness is used. x Ga (1-x) The N-layer ensures the carrier concentration provided by the first semiconductor layer.

[0136] In this embodiment of the disclosure, along the direction from the first semiconductor layer to the second semiconductor layer, a plurality of C-doped Al atoms are formed. y Ga (1-y) The growth temperature of the N layer gradually decreases, and multiple C-doped Al layers are added. y Ga (1-y) The growth pressure of the N layer remains unchanged.

[0137] In this implementation, C is doped with Al y Ga (1-y) The gradual decrease in the growth temperature of the N-layer can help release the accumulated stress in the initially grown GaN layer, reducing the stress during the growth of multiple quantum wells and decreasing the well-barrier polarization effect; moreover, when C is doped with Al... y Ga (1-y) When the N-layer grows at a low temperature, its growth thickness is relatively thinner, ensuring that the overall crystal quality does not degrade.

[0138] In some examples of embodiments of this disclosure, multiple C-doped Al y Ga (1-y) The growth temperature of the N-layer can decrease at an arithmetic or proportional rate.

[0139] In other examples of embodiments of this disclosure, multiple C-doped Al y Ga (1-y) The way the growth temperature of the N-layer decreases can be irregular.

[0140] In this embodiment of the disclosure, along the direction from the first semiconductor layer to the second semiconductor layer, a plurality of N-type doped Al atoms are... x Ga (1-x) The growth temperature and growth pressure of the N layer remain unchanged.

[0141] The growth process of the first semiconductor layer is illustrated below using three cycles as an example: The first step involves introducing NH3 and TMGa sources, along with SiH4, after the undoped GaN layer has grown. The first N-type doped Al layer is then grown at a growth temperature of 1100–1200 °C and a growth pressure of 100–300 Torr. x Ga (1-x) N layers.

[0142] For example, the first layer of N-type doped Al was grown at a growth temperature of 1150℃ and a growth pressure of 200 Torr. x Ga (1-x) N layers.

[0143] The second step is to dope Al in the first N-type layer. x Ga (1-x) After the N-layer growth is complete, NH3, TMGa, and TMAl sources are introduced, along with C2H4. The first C-doped Al layer is grown at a growth temperature of 1000–1100 °C and a growth pressure of 100–200 Torr. y Ga (1-y) N layers.

[0144] For example, the first layer of C-doped Al was grown at a growth temperature of 1050℃ and a growth pressure of 150 Torr. y Ga (1-y) N layers.

[0145] The third step is to dope Al in the first layer of C. y Ga (1-y) After the N-layer growth is complete, NH3 and TMGa sources are introduced, along with SiH4. The second N-type doped Al layer is grown at a growth temperature of 1100–1200 °C and a growth pressure of 100–300 Torr. x Ga (1-x) N layers.

[0146] For example, a second layer of N-type doped Al was grown at a growth temperature of 1150℃ and a growth pressure of 200 Torr. x Ga (1-x) N layers.

[0147] The fourth step is to dope Al in the second N-type layer. x Ga (1-x)After the N-layer growth is complete, NH3, TMGa, and TMAl sources are introduced, along with C2H4. The second C-doped Al layer is grown at a growth temperature of 900–1000 °C and a growth pressure of 100–200 Torr. y Ga (1-y) N layers.

[0148] For example, a second layer of C-doped Al is grown at a growth temperature of 950℃ and a growth pressure of 150 Torr. y Ga (1-y) N layers.

[0149] The fifth step is to dope Al in the second C layer. y Ga (1-y) After the N-layer growth was completed, NH3 and TMGa sources were introduced, along with SiH4. The third N-type doped Al layer was grown at a growth temperature of 1100–1200 °C and a growth pressure of 100–300 Torr. x Ga (1-x) N layers.

[0150] For example, a third layer of N-type doped Al was grown at a growth temperature of 1150℃ and a growth pressure of 200 Torr. x Ga (1-x) N layers.

[0151] Step 6: Doping Al with N-type in the third layer x Ga (1-x) After the N-layer growth is complete, NH3, TMGa, and TMAl sources are introduced, along with C2H4. The third C-doped Al layer is grown at a growth temperature of 800–900 °C and a growth pressure of 100–200 Torr. y Ga (1-y) N layers.

[0152] For example, a third layer of C-doped Al was grown at a growth temperature of 850℃ and a growth pressure of 150 Torr. y Ga (1-y) N layers.

[0153] S205: A multi-quantum-well layer is grown on the first semiconductor layer.

[0154] In this embodiment of the disclosure, the multiple quantum well layer 102 can be a superlattice structure composed of a quantum well layer and a quantum barrier layer.

[0155] The quantum well layer can be an InGaN quantum well layer, and the quantum barrier layer can be a GaN quantum barrier layer.

[0156] In the embodiments disclosed herein, the thickness of the InGaN quantum well layer is 2-4 nm, the In content in the InGaN well layer is 0.1-0.4, and the thickness of the GaN quantum barrier layer is 5-15 nm.

[0157] For example, the InGaN quantum well layer has a thickness of 3 nm, the In content in the InGaN well layer is 0.2, and the GaN quantum barrier layer has a thickness of 10 nm.

[0158] In this embodiment of the disclosure, the multi-quantum well layer 102 may include 5 to 15 cycles.

[0159] For example, the multi-quantum well layer 102 may include 10 cycles.

[0160] In this embodiment of the present disclosure, after the first semiconductor layer is grown, NH3, TEGa, and TMI sources are introduced to grow a multi-quantum well layer.

[0161] In this embodiment of the disclosure, step S205 may include: The InGaN layer is grown at a growth temperature of 800~900℃ and a growth pressure of 100~300 torr. The GaN layer is grown in an environment with a growth temperature of 900~1000℃ and a growth pressure of 100~300 torr; Repeat the above steps multiple times to obtain the multi-quantum well layer.

[0162] For example, the InGaN layer is grown at a growth temperature of 850°C and a growth pressure of 200 torr; The GaN layer was grown at a growth temperature of 950°C and a growth pressure of 200 torr.

[0163] S206: An electron blocking layer is grown on a multi-quantum-well layer.

[0164] In this embodiment of the disclosure, after the multi-quantum well layer is grown, NH3, TEGa and TMAl sources are introduced to grow an electron blocking layer.

[0165] In this embodiment of the disclosure, step S206 may include: An AlGaN layer of 50-100 nm was grown at a growth temperature of 950-1050℃ and a growth pressure of 50-100 Torr to serve as an electron blocking layer.

[0166] For example, an 80nm AlGaN layer was grown at a growth temperature of 1000℃ and a growth pressure of 80Torr.

[0167] In the embodiments disclosed herein, the Al content in the AlGaN layer is between 0.1 and 0.5.

[0168] S207: A second semiconductor layer is grown on the electron blocking layer.

[0169] In this embodiment of the disclosure, after the electron blocking layer is grown, NH3, TEGa and Cp2Mg are introduced to grow a second semiconductor layer.

[0170] In this embodiment of the disclosure, step S207 may include: A 30-100 nm P-type GaN layer is grown at a growth temperature of 950-1050℃ and a growth pressure of 100-600 Torr as the second semiconductor layer.

[0171] For example, a 50 nm P-type GaN layer was grown at a growth temperature of 1000 °C and a growth pressure of 400 Torr.

[0172] In this embodiment, the doping concentration of Mg in the P-type GaN layer can be 1×10⁻⁶. 19 ~5×10 21 cm -3 .

[0173] S208: A contact layer is grown on the second semiconductor layer.

[0174] In this embodiment of the present disclosure, after the second semiconductor layer is grown, NH3, TEGa and Cp2Mg are introduced to grow a contact layer.

[0175] In this embodiment of the disclosure, step S208 may include: P-type GaN contact layers of 10-30 nm were grown at a growth temperature of 1000-1100℃ and a growth pressure of 100-300 Torr.

[0176] For example, a 20 nm P-type GaN contact layer was grown at a growth temperature of 1050 °C and a growth pressure of 200 Torr.

[0177] In this embodiment, the doping concentration of Mg in the P-type GaN contact layer can be 1×10⁻⁶. 19 ~5×10 21 cm -3 .

[0178] After step S208, the method may further include: The reaction chamber temperature was lowered, and the cells were annealed in a nitrogen atmosphere at a temperature range of 650~850℃ for 5~15 minutes. The cells were then cooled to room temperature, and the epitaxial growth was completed.

[0179] It should be noted that, Figure 5 The method for fabricating the light-emitting diode shown is relatively... Figure 4 The method for fabricating a light-emitting diode shown provides a more detailed approach to the growth of light-emitting diodes.

[0180] It should be noted that, in the embodiments disclosed herein, a PVD equipment and a Veeco K465iorC4orRB MOCVD equipment are used to realize the growth method of light-emitting diodes. Trimethylaluminum (TMAl), trimethylgallium (TMGa) and / or triethylgallium (TEGa) and trimethylaluminum indium (TMIn) are used as precursors for group III sources, ammonia (NH3) is used as a precursor for group V sources, silane (SiH4) and magnesium pyrocene (Cp2Mg) are used as precursors for N-type dopant and P-type dopant, respectively, ethylene (C2H4) is used as a precursor for carbon doping, and nitrogen and hydrogen are used as carrier gases.

[0181] After testing, the embodiments of this disclosure were applied to green light-emitting diodes, fabricated into chips with a size of 9*24mil, and subjected to a 120mA current test. The test data are shown in Table 1 below: Table 1

[0182] As shown in Table 1, when this embodiment of the present disclosure is applied to a light-emitting diode, the luminous brightness is increased from 214mW to 223mW, the forward operating voltage is reduced from 3.12V to 3.03V, the ESD yield is increased from 92.6% to 96.8%, and the reverse breakdown voltage is increased from 45V to 58V.

[0183] In Table 1, ESD-6kV (%) refers to the percentage (%) of LED products that still function normally after a 6 kV electrostatic discharge (ESD) test. This indicator has also seen a slight improvement.

[0184] The above description is only a preferred embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A light-emitting diode, characterized in that, The light-emitting diode includes a first semiconductor layer (101), a second semiconductor layer (103), and a multi-quantum well layer (102) located between the first semiconductor layer (101) and the second semiconductor layer (103). The first semiconductor layer (101) comprises multiple periodically alternating layers of N-type doped Al. x Ga (1-x) N-layer (111) and C-doped Al y Ga (1-y) Nth layer (112); Among them, 0 <x≤1,0<y≤1。 2. The light-emitting diode according to claim 1, characterized in that, Along the direction from the first semiconductor layer (101) to the second semiconductor layer (103), the plurality of C-doped Al y Ga (1-y) The doping concentration of C in the N layer (112) gradually decreases.

3. The light-emitting diode according to claim 2, characterized in that, Along the direction from the first semiconductor layer (101) to the second semiconductor layer (103), the plurality of C-doped Al y Ga (1-y) The thickness of layer N (112) gradually decreases.

4. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The first semiconductor layer (101) comprises three alternating N-type doped Al layers. x Ga (1-x) N-layer (111) and C-doped Al y Ga (1-y) Nth layer (112).

5. The light-emitting diode according to claim 4, characterized in that, Along the direction from the first semiconductor layer (101) to the second semiconductor layer (103), the plurality of C-doped Al y Ga (1-y) The C doping concentration in the N layer (112) is 1×10 18 ~2×10 18 cm -3 5×10 17 ~1×10 18 cm -3 1×10 17 ~5×10 17 cm -3 .

6. The light-emitting diode according to claim 5, characterized in that, Along the direction from the first semiconductor layer (101) to the second semiconductor layer (103), the plurality of C-doped Al y Ga (1-y) The thicknesses of the N layer (112) are 150~200nm, 100~150nm, and 50~100nm, respectively.

7. The light-emitting diode according to any one of claims 1 to 3, characterized in that, Multiple N-type doped Al x Ga (1-x) The N layer (111) is a Si-doped GaN layer.

8. The light-emitting diode according to claim 7, characterized in that, The N-type doped Al x Ga (1-x) The Si doping concentration in the N-layer (111) is 1×10⁻⁶. 19 ~1×10 21 cm -3 .

9. The light-emitting diode according to claim 7, characterized in that, The N-type doped Al x Ga (1-x) The thickness of the N layer (111) is 0.5~1μm.

10. A method for fabricating a light-emitting diode, characterized in that, The preparation method includes: A first semiconductor layer is grown, the first semiconductor layer comprising multiple N-type doped Al layers stacked alternately in a periodic manner. x Ga (1-x) N-layer and C-doped Al y Ga (1-y) N layers; where 0 <x≤1,0<y≤1; A multi-quantum-well layer is grown on the first semiconductor layer; A second semiconductor layer is grown on the multi-quantum-well layer.

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