GaN-based HEMT epitaxial wafer and preparation method and application thereof

Abstract

The invention relates to a GaN-based HEMT (High Electron Mobility Transistor) epitaxial wafer and a preparation method and application thereof, in particular to the field of semiconductor materials, the GaN-based HEMT epitaxial wafer comprises a substrate, and a nucleating layer, a high-resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer which are sequentially arranged on the substrate from bottom to top; the high-resistance layer comprises a P-type AlGaN layer and an N-type GaN layer which are arranged in an alternate and matched mode in the direction perpendicular to the arrangement direction of the high-resistance layer. According to the GaN-based HEMT epitaxial wafer provided by the invention, the specific high-resistance layer is designed, and the high-resistance layer with high crystal growth quality is obtained by using the specific structure and the formed high-resistance layer, so that electric leakage is avoided, and the voltage resistance of a device is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor materials, and in particular to a GaN-based HEMT epitaxial wafer and a preparation method and application thereof. Background Art

[0002] At present, as the representative of the third generation wide bandgap semiconductor materials, gallium nitride (GaN) has attracted more and more attention due to its wider bandgap, larger critical breakdown electric field, high saturation electron velocity, high temperature resistance, radiation resistance, good thermal conductivity, and small dielectric constant. The two-dimensional electron gas with high electron concentration and high electron mobility that can be formed at the AlGaN / GaN heterojunction interface has great potential application value in high-power, high-voltage HEMT devices.

[0003] The existing epitaxial growth method of GaN-based high electron mobility transistors (HEMTs) is to directly grow an AlN buffer layer, an AlxGa1-xN buffer layer, a GaN high resistance layer, a GaN channel layer, an AlN insertion layer and an AlGaN barrier layer in sequence on a substrate (silicon or sapphire); among them, the high resistance layer can serve as an effective electron blocking layer due to its high resistance characteristics, which helps to form a two-dimensional electron gas with high electron mobility in the AlGaN / GaN heterostructure. The current method for obtaining a GaN high resistance layer is to introduce high concentrations of impurities such as Fe and C during the epitaxial growth process to obtain the high resistance layer.

[0004] For example, CN115360236A discloses a GaN HEMT device with a high-resistance buffer layer and a preparation method thereof, wherein the device comprises a substrate, an AlN nucleation layer, a stress regulation layer, a high-resistance buffer layer, a GaN channel layer, an AlN insertion layer, an AlGaN barrier layer and a GaN cap layer arranged in sequence from bottom to top, wherein the high-resistance buffer layer comprises an Fe-doped GaN buffer layer, a hexagonal BN buffer layer and a C-doped GaN buffer layer in sequence from bottom to top; a source electrode, a drain electrode and a gate electrode spaced apart from each other are arranged on the upper surface of the GaN cap layer, the source electrode and the drain electrode form an ohmic contact with the AlGaN barrier layer; and the gate electrode forms a Schottky contact with the AlGaN barrier layer.

[0005] However, when high concentrations of impurities such as Fe and C are introduced during the epitaxial growth process to obtain a high resistance layer, due to the memory effect of iron doping, it is difficult to control the concentration of iron impurities, resulting in poor crystal quality. At the same time, carbon doping is easy to carry out under low temperature and low pressure, but the crystal quality of the epitaxial layer obtained under low temperature and low pressure will deteriorate. Therefore, there is an urgent need for a preparation process that can effectively improve the quality of high resistance layer crystal growth. Summary of the invention

[0006] In view of the problems existing in the prior art, the object of the present invention is to provide a GaN-based HEMT epitaxial wafer and a preparation method and use thereof, so as to solve the defects of poor quality of high-resistance layer crystal growth and leakage.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a GaN-based HEMT epitaxial wafer, wherein the GaN-based HEMT epitaxial wafer comprises:

[0009] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0010] The high resistance layer comprises a P-type AlGaN layer and an N-type GaN layer which are alternately arranged perpendicular to the arrangement direction of the high resistance layer.

[0011] The GaN-based HEMT epitaxial wafer provided by the present invention obtains a high-resistance layer with high crystal growth quality by designing a specific high-resistance layer and utilizing the high-resistance layer with a specific structure and composition, which is beneficial to avoiding leakage and thus improving the voltage resistance performance of the device.

[0012] As a preferred technical solution of the present invention, the nucleation layer is an AlN nucleation layer with a thickness of 15-20 nm.

[0013] As a preferred technical solution of the present invention, the high resistance layer is an N-type GaN layer provided with a first groove and a P-type AlGaN layer provided in the first groove;

[0014] Alternatively, the high resistance layer is a P-type AlGaN layer provided with a second groove and an N-type GaN layer provided in the second groove.

[0015] Preferably, the thickness of the N-type GaN layer provided with the first groove is 5-20 μm.

[0016] Preferably, the first groove has a depth of 5-20 μm.

[0017] Preferably, the width of the first groove is 2-2.5 μm.

[0018] Preferably, the thickness of the P-type AlGaN layer disposed in the first groove is equal to the depth of the first groove.

[0019] Preferably, the thickness of the P-type AlGaN layer provided with the second groove is 5-20 μm.

[0020] Preferably, the second groove has a depth of 5-20 μm.

[0021] Preferably, the width of the second groove is 2-2.5 μm.

[0022] Preferably, the thickness of the N-type GaN layer disposed in the second groove is equal to the depth of the second groove.

[0023] As a preferred technical solution of the present invention, the channel layer is a GaN channel layer with a thickness of 50-200 nm.

[0024] Preferably, the insertion layer is an AlN insertion layer with a thickness of 1-1.5 nm.

[0025] Preferably, the barrier layer is an AlGaN barrier layer with a thickness of 20-30 nm.

[0026] Preferably, the capping layer is a GaN capping layer with a thickness of 10-20 nm.

[0027] In a second aspect, the present invention provides a method for preparing a GaN-based HEMT epitaxial wafer as described in the first aspect, the preparation method comprising:

[0028] The AlN nucleation layer growth, the P-type AlGaN-N-type GaN high resistance layer growth, the GaN channel layer growth, the AlN insertion layer growth, the AlGaN barrier layer growth and the GaN cap layer growth are sequentially performed on the substrate to obtain a GaN-based HEMT epitaxial wafer.

[0029] As a preferred technical solution of the present invention, the growth temperature of the AlN nucleation layer is 600-1200°C.

[0030] Preferably, the growth pressure of the AlN nucleation layer is 50-200 mbr.

[0031] Preferably, the thickness of the AlN nucleation layer obtained by growing the AlN nucleation layer is 15-20 nm.

[0032] As a preferred technical solution of the present invention, the growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence.

[0033] Preferably, the base layer growth includes N-type GaN layer growth or P-type AlGaN layer growth.

[0034] Preferably, when the base layer growth is N-type GaN layer growth, the trench filling growth is P-type AlGaN trench filling growth.

[0035] Preferably, the carrier gas used in the growth of the N-type GaN layer includes nitrogen.

[0036] Preferably, the flow rate of the carrier gas used in the growth of the N-type GaN layer is 50-100 slm.

[0037] Preferably, the Ga source used in the growth of the N-type GaN layer includes TMGa.

[0038] Preferably, the flow rate of the Ga source used in the growth of the N-type GaN layer is 100-500 sccm.

[0039] Preferably, the nitrogen source used in the growth of the N-type GaN layer includes ammonia.

[0040] Preferably, the flow rate of the nitrogen source used in the growth of the N-type GaN layer is 10-50 slm.

[0041] Preferably, the silicon source used in the growth of the N-type GaN layer includes silane.

[0042] Preferably, the flow rate of the silicon source used in the growth of the N-type GaN layer is 50-100 sccm.

[0043] Preferably, the growth temperature of the N-type GaN layer is 1000-1100°C.

[0044] Preferably, the growth pressure during the growth of the N-type GaN layer is 50-600 mbar.

[0045] Preferably, the doping concentration of the N-type GaN layer obtained by growing the N-type GaN layer is 1×10 17 -1×10 18 atom / cm 3 .

[0046] Preferably, the carrier gas used in the P-type AlGaN trench filling growth includes nitrogen.

[0047] Preferably, the flow rate of the carrier gas used in the P-type AlGaN trench filling growth is 50-100 slm.

[0048] Preferably, the Ga source used in the P-type AlGaN trench filling growth includes TMGa.

[0049] Preferably, the flow rate of the Ga source used in the P-type AlGaN trench filling growth is 100-500 sccm.

[0050] Preferably, the nitrogen source used in the P-type AlGaN trench filling growth includes ammonia.

[0051] Preferably, the flow rate of the nitrogen source used in the P-type AlGaN trench filling growth is 10-50 slm.

[0052] Preferably, the aluminum source used in the P-type AlGaN trench filling growth includes TMAl.

[0053] Preferably, the flow rate of the aluminum source used in the P-type AlGaN trench filling growth is 50-200 sccm.

[0054] Preferably, the growth temperature of the P-type AlGaN trench filling growth is 1000-1100°C.

[0055] Preferably, the growth pressure of the P-type AlGaN trench filling growth is 300-500 mbar.

[0056] Preferably, the doping concentration of the P-type AlGaN layer obtained by the P-type AlGaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 .

[0057] Preferably, when the base layer growth is a P-type AlGaN layer growth, the trench filling growth is an N-type GaN trench filling growth.

[0058] Preferably, the carrier gas used in the growth of the P-type AlGaN layer includes nitrogen.

[0059] Preferably, the flow rate of the carrier gas used in the growth of the P-type AlGaN layer is 50-100 slm.

[0060] Preferably, the Ga source used in the growth of the P-type AlGaN layer includes TMGa.

[0061] Preferably, the flow rate of the Ga source used in the growth of the P-type AlGaN layer is 100-500 sccm.

[0062] Preferably, the nitrogen source used in the growth of the P-type AlGaN layer includes ammonia.

[0063] Preferably, the flow rate of the nitrogen source used in the growth of the P-type AlGaN layer is 10-50 slm.

[0064] Preferably, the aluminum source used in the growth of the P-type AlGaN layer includes TMAl.

[0065] Preferably, the flow rate of the aluminum source used in the growth of the P-type AlGaN layer is 50-200 sccm.

[0066] Preferably, the growth temperature of the P-type AlGaN layer is 1000-1100°C.

[0067] Preferably, the growth pressure of the P-type AlGaN layer is 300-500 mbar.

[0068] Preferably, the doping concentration of the P-type AlGaN layer obtained by growing the P-type AlGaN layer is 1×1017 -1×10 18 atom / cm 3 .

[0069] Preferably, the carrier gas used in the N-type GaN trench filling growth includes nitrogen.

[0070] Preferably, the flow rate of the carrier gas used in the N-type GaN trench filling growth is 50-100 slm.

[0071] Preferably, the Ga source used in the N-type GaN trench filling growth includes TMGa.

[0072] Preferably, the flow rate of the Ga source used in the N-type GaN trench filling growth is 100-500 sccm.

[0073] Preferably, the nitrogen source used in the N-type GaN trench filling growth includes ammonia.

[0074] Preferably, the flow rate of the nitrogen source used in the N-type GaN trench filling growth is 10-50 slm.

[0075] Preferably, the silicon source used in the N-type GaN trench filling growth includes silane.

[0076] Preferably, the flow rate of the silicon source used in the N-type GaN trench filling growth is 50-100 sccm.

[0077] Preferably, the growth temperature of the N-type GaN trench filling growth is 1000-1100°C.

[0078] Preferably, the growth pressure of the N-type GaN trench filling growth is 50-600 mbar.

[0079] Preferably, the doping concentration of the N-type GaN layer obtained by the N-type GaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 .

[0080] Preferably, the thickness of the base layer obtained by growing the base layer is 5-20 μm.

[0081] Preferably, the base layer trench is etched by mask etching.

[0082] Preferably, the sidewall inclination angle of the groove obtained by etching the base layer groove is 86-90°.

[0083] Preferably, the depth of the grooves obtained by etching the base layer grooves is 5-20 μm.

[0084] Preferably, the width of the grooves obtained by etching the base layer grooves is 2-2.5 μm.

[0085] As a preferred technical solution of the present invention, the carrier gas used in the growth of the GaN channel layer includes nitrogen.

[0086] Preferably, the flow rate of the carrier gas used in the growth of the GaN channel layer is 50-100 slm.

[0087] Preferably, the Ga source used in the growth of the GaN channel layer includes TMGa.

[0088] Preferably, the flow rate of the Ga source used in the growth of the GaN channel layer is 100-200 sccm.

[0089] Preferably, the nitrogen source used in the growth of the GaN channel layer includes ammonia.

[0090] Preferably, the flow rate of the nitrogen source used in the growth of the GaN channel layer is 10-50 slm.

[0091] Preferably, the growth temperature of the GaN channel layer is 1100-1120°C.

[0092] Preferably, the growth pressure of the GaN channel layer is 100-200 mbar.

[0093] Preferably, the GaN channel layer grown by the GaN channel layer has a thickness of 50-200 nm.

[0094] Preferably, the carrier gas used in the growth of the AlN insertion layer includes nitrogen.

[0095] Preferably, the flow rate of the carrier gas used in the growth of the AlN insertion layer is 50-100 slm.

[0096] Preferably, the aluminum source used in the growth of the AlN insertion layer includes TMAl.

[0097] Preferably, the flow rate of the aluminum source used in the growth of the AlN insertion layer is 40-60 sccm.

[0098] Preferably, the nitrogen source used in the growth of the AlN insertion layer includes ammonia.

[0099] Preferably, the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 1-5 slm.

[0100] Preferably, the growth temperature of the AlN insertion layer is 1100-1120°C.

[0101] Preferably, the growth pressure of the AlN insertion layer is 100-200 mbar.

[0102] Preferably, the thickness of the AlN insertion layer obtained by growing the AlN insertion layer is 1-1.5 nm.

[0103] As a preferred technical solution of the present invention, the carrier gas used in the growth of the AlGaN barrier layer includes nitrogen.

[0104] Preferably, the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 50-100 slm.

[0105] Preferably, the Ga source used for growing the AlGaN barrier layer includes TMGa.

[0106] Preferably, the flow rate of the Ga source used for growing the AlGaN barrier layer is 50-100 sccm.

[0107] Preferably, the nitrogen source used for growing the AlGaN barrier layer includes ammonia.

[0108] Preferably, the flow rate of the nitrogen source used for growing the AlGaN barrier layer is 1-5 slm.

[0109] Preferably, the aluminum source used for growing the AlGaN barrier layer includes TMAl.

[0110] Preferably, the flow rate of the aluminum source used for growing the AlGaN barrier layer is 50-200 sccm.

[0111] Preferably, the growth temperature of the AlGaN barrier layer is 1100-1120°C.

[0112] Preferably, the growth pressure of the AlGaN barrier layer is 100-200 mbar.

[0113] Preferably, the thickness of the AlGaN barrier layer obtained by growing the AlGaN barrier layer is 20-30 nm.

[0114] Preferably, the carrier gas used for growing the GaN cap layer includes nitrogen.

[0115] Preferably, the flow rate of the carrier gas used for growing the GaN cap layer is 50-100 slm.

[0116] Preferably, the Ga source used for growing the GaN cap layer includes TMGa.

[0117] Preferably, the flow rate of Ga source used for growing the GaN cap layer is 30-60 sccm.

[0118] Preferably, the nitrogen source used for growing the GaN cap layer includes ammonia.

[0119] Preferably, the flow rate of the nitrogen source used for growing the GaN cap layer is 1-5 slm.

[0120] Preferably, the growth temperature of the GaN capping layer is 1110-1120°C.

[0121] Preferably, the growth pressure of the GaN cap layer is 100-200 mbar.

[0122] Preferably, the thickness of the GaN capping layer obtained by growing the GaN capping layer is 10-20 nm.

[0123] In a third aspect, the present invention provides a use of the GaN-based HEMT epitaxial wafer as described in the first aspect, the use comprising:

[0124] The GaN-based HEMT epitaxial wafer is used to prepare a power device.

[0125] Compared with the prior art solutions, the present invention has the following beneficial effects:

[0126] The GaN-based HEMT epitaxial wafer provided by the present invention improves the crystal growth quality of the obtained high-resistance layer by means of a specially designed high-resistance layer and utilizes the matching relationship between the P-type AlGaN layer and the N-type GaN layer, thereby improving the withstand voltage performance of the power device and facilitating improvement of leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0127] Figure 1 is a schematic diagram of a GaN-based HEMT epitaxial wafer provided by an embodiment of the present invention;

[0128] Figure 2 is a schematic diagram of a GaN-based HEMT epitaxial wafer provided in Example 1 of the present invention;

[0129] Figure 3 is a schematic diagram of a GaN-based HEMT epitaxial wafer provided in Example 2 of the present invention;

[0130] Figure 4 is a schematic diagram of a GaN-based HEMT epitaxial wafer provided in Example 3 of the present invention;

[0131] Figure 5 It is a schematic diagram of a GaN-based HEMT epitaxial wafer provided in Example 4 of the present invention.

[0132] In the figure: 1-substrate, 2-nucleation layer, 3-high resistance layer, 3.1-N-type GaN layer, 3.2-P-type AlGaN layer, 4-channel layer, 5-insertion layer, 6-barrier layer, 7-cap layer.

[0133] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims. DETAILED DESCRIPTION

[0134] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0135] This embodiment provides a GaN-based HEMT epitaxial wafer, such as Figure 1 As shown, the GaN-based HEMT epitaxial wafer includes:

[0136] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0137] The high resistance layer comprises a P-type AlGaN layer and an N-type GaN layer which are alternately arranged perpendicular to the arrangement direction of the high resistance layer.

[0138] In the present invention, the high resistance layer is set in a direction perpendicular to the substrate surface. At this time, the direction perpendicular to the high resistance layer setting direction is along the substrate surface, and the P-type AlGaN layer and the N-type GaN layer are alternately set. For example, if the substrate is taken as a reference and an xyz three-axis coordinate system is adopted, the z-axis is perpendicular to the substrate surface, which is the high resistance layer setting direction of the present invention. At this time, the y-axis or the x-axis is perpendicular to the high resistance layer setting direction.

[0139] The nucleation layer is an AlN nucleation layer with a thickness of 15-20 nm, for example, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm or 20 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0140] Wherein, the high resistance layer is an N-type GaN layer provided with a first groove and a P-type AlGaN layer provided in the first groove;

[0141] Alternatively, the high resistance layer is a P-type AlGaN layer provided with a second groove and an N-type GaN layer provided in the second groove.

[0142] Among them, the thickness of the N-type GaN layer provided with the first groove is 5-20μm, for example, it can be 5μm, 6μm, 8μm, 10μm, 12μm, 14μm, 16μm, 18μm or 20μm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0143] The depth of the first groove is 5-20 μm, for example, 5 μm, 6 μm, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm or 20 μm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0144] The width of the first groove is 2-2.5 μm, for example, 2 μm, 2.1 μm, 2.2 μm, 2.3 μm, 2.4 μm or 2.5 μm, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0145] Wherein, the thickness of the P-type AlGaN layer disposed in the first groove is equal to the depth of the first groove.

[0146] Among them, the thickness of the P-type AlGaN layer provided with the second groove is 5-20μm, for example, it can be 5μm, 6μm, 8μm, 10μm, 12μm, 14μm, 16μm, 18μm or 20μm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0147] The depth of the second groove is 5-20 μm, for example, 5 μm, 6 μm, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm or 20 μm, but is not limited to the listed values. Other values ​​not listed within the range also meet the requirements.

[0148] The width of the second groove is 2-2.5 μm, for example, 2 μm, 2.1 μm, 2.2 μm, 2.3 μm, 2.4 μm or 2.5 μm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0149] Wherein, the thickness of the N-type GaN layer disposed in the second groove is equal to the depth of the second groove.

[0150] The channel layer is a GaN channel layer with a thickness of 50-200 nm, for example, 50 nm, 60 nm, 80 nm, 100 nm, 120 nm, 140 nm, 160 nm, 180 nm or 200 nm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0151] The insertion layer is an AlN insertion layer with a thickness of 1-1.5 nm, for example, 1 nm, 1.1 nm, 1.2 nm, 1.3 nm, 1.4 nm or 1.5 nm, etc., but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0152] The barrier layer is an AlGaN barrier layer with a thickness of 20-30 nm, for example, 20 nm, 22 nm, 24 nm, 26 nm, 28 nm or 30 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0153] The capping layer is a GaN capping layer with a thickness of 10-20 nm, for example, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm or 20 nm, etc., but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0154] Furthermore, the present invention provides a method for preparing a GaN-based HEMT epitaxial wafer, the preparation method comprising:

[0155] The AlN nucleation layer growth, the P-type AlGaN-N-type GaN high resistance layer growth, the GaN channel layer growth, the AlN insertion layer growth, the AlGaN barrier layer growth and the GaN cap layer growth are sequentially performed on the substrate to obtain a GaN-based HEMT epitaxial wafer.

[0156] The growth temperature of the AlN nucleation layer is 600-1200°C, for example, 600°C, 700°C, 800°C, 900°C, 1000°C, 1100°C or 1200°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0157] Among them, the growth pressure of the AlN nucleation layer is 50-200mbar, for example, it can be 50mbar, 60mbar, 80mbar, 100mbar, 120mbar, 140mbar, 160mbar, 180mbar or 200mbar, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0158] The thickness of the AlN nucleation layer obtained by growing the AlN nucleation layer is 15-20 nm, for example, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm or 20 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0159] The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence.

[0160] Wherein, the base layer growth includes N-type GaN layer growth or P-type AlGaN layer growth.

[0161] Wherein, when the base layer growth is N-type GaN layer growth, the trench filling growth is P-type AlGaN trench filling growth.

[0162] Wherein, the carrier gas used in the growth of the N-type GaN layer includes nitrogen.

[0163] The flow rate of the carrier gas used in the growth of the N-type GaN layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0164] Wherein, the Ga source used in the growth of the N-type GaN layer includes TMGa.

[0165] The flow rate of the Ga source used in the growth of the N-type GaN layer is 100-500 sccm, for example, 100 sccm, 200 sccm, 300 sccm, 400 sccm or 500 sccm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0166] Wherein, the nitrogen source used in the growth of the N-type GaN layer includes ammonia.

[0167] The flow rate of the nitrogen source used in the growth of the N-type GaN layer is 10-50 slm, for example, 10 slm, 20 slm, 30 slm, 40 slm or 50 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0168] Wherein, the silicon source used in the growth of the N-type GaN layer includes silane.

[0169] Among them, the flow rate of the silicon source used in the growth of the N-type GaN layer is 50-100sccm, for example, it can be 50sccm, 60sccm, 70sccm, 80sccm, 90sccm or 100sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0170] The growth temperature of the N-type GaN layer is 1000-1100°C, for example, 1000°C, 1020°C, 1040°C, 1060°C, 1080°C or 1100°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0171] Among them, the growth pressure during the growth of the N-type GaN layer is 50-600mbar, for example, it can be 50mbar, 60mbar, 80mbar, 100mbar, 200mbar, 300mbar, 400mbar, 500mbar or 600mbar, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0172] The doping concentration of the N-type GaN layer obtained by growing the N-type GaN layer is 1×10 17 -1×10 18 atom / cm 3 , for example, it can be 1×10 17 atom / cm 3 , 2×10 17 atom / cm 3 , 4×10 17 atom / cm 3 , 6×10 17 atom / cm 3 , 8×10 17 atom / cm 3 or 1×10 18 atom / cm 3 The above values ​​are not limited to the above values. Other values ​​not listed in the above values ​​also meet the requirements.

[0173] In the present invention, atom / cm 3 Refers to the number of atoms contained in a unit volume.

[0174] Wherein, the carrier gas used in the P-type AlGaN trench filling growth includes nitrogen.

[0175] The flow rate of the carrier gas used in the P-type AlGaN trench filling growth is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0176] Wherein, the Ga source used in the P-type AlGaN trench filling growth includes TMGa.

[0177] Among them, the flow rate of the Ga source used in the P-type AlGaN trench filling growth is 100-500sccm, for example, it can be 100sccm, 200sccm, 300sccm, 400sccm or 500sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0178] Wherein, the nitrogen source used in the P-type AlGaN trench filling growth includes ammonia.

[0179] The flow rate of the nitrogen source used in the P-type AlGaN trench filling growth is 10-50 slm, for example, 10 slm, 20 slm, 30 slm, 40 slm or 50 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0180] Wherein, the aluminum source used in the P-type AlGaN trench filling growth includes TMAl.

[0181] Among them, the flow rate of the aluminum source used in the P-type AlGaN trench filling growth is 50-200sccm, for example, it can be 50sccm, 60sccm, 80sccm, 100sccm, 120sccm, 140sccm, 160sccm, 180sccm or 200sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0182] The growth temperature of the P-type AlGaN trench filling growth is 1000-1100°C, for example, it can be 1000°C, 1020°C, 1040°C, 1060°C, 1080°C or 1100°C, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0183] The growth pressure of the P-type AlGaN trench filling growth is 300-500 mbar, for example, 300 mbar, 350 mbar, 400 mbar, 450 mbar or 500 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0184] The doping concentration of the P-type AlGaN layer obtained by the P-type AlGaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 , for example, it can be 1×10 17 atom / cm 3 , 2×10 17 atom / cm 3 , 4×10 17 atom / cm 3 , 6×10 17 atom / cm 3 , 8×10 17 atom / cm 3 or 1×10 18 atom / cm 3The above values ​​are not limited to the above values. Other values ​​not listed in the above values ​​also meet the requirements.

[0185] Wherein, when the base layer growth is a P-type AlGaN layer growth, the trench filling growth is an N-type GaN trench filling growth.

[0186] Wherein, the carrier gas used in the growth of the P-type AlGaN layer includes nitrogen.

[0187] The flow rate of the carrier gas used in the growth of the P-type AlGaN layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0188] Wherein, the Ga source used in the growth of the P-type AlGaN layer includes TMGa.

[0189] The flow rate of the Ga source used in the growth of the P-type AlGaN layer is 100-500sccm, for example, 100sccm, 200sccm, 300sccm, 400sccm or 500sccm, etc., but is not limited to the listed values, and other values ​​not listed in this range also meet the requirements.

[0190] Wherein, the nitrogen source used in the growth of the P-type AlGaN layer includes ammonia.

[0191] The flow rate of the nitrogen source used in the growth of the P-type AlGaN layer is 10-50 slm, for example, 10 slm, 20 slm, 30 slm, 40 slm or 50 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0192] Wherein, the aluminum source used in the growth of the P-type AlGaN layer includes TMAl.

[0193] Among them, the flow rate of the aluminum source used in the growth of the P-type AlGaN layer is 50-200sccm, for example, it can be 50sccm, 60sccm, 80sccm, 100sccm, 120sccm, 140sccm, 160sccm, 180sccm or 200sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0194] The growth temperature of the P-type AlGaN layer is 1000-1100°C, for example, 1000°C, 1020°C, 1040°C, 1060°C, 1080°C or 1100°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0195] The growth pressure of the P-type AlGaN layer is 300-500 mbar, for example, 300 mbar, 350 mbar, 400 mbar, 450 mbar or 500 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0196] The doping concentration of the P-type AlGaN layer obtained by growing the P-type AlGaN layer is 1×10 17 -1×10 18 atom / cm 3 , for example, it can be 1×10 17 atom / cm 3 , 2×10 17 atom / cm 3 , 4×10 17 atom / cm 3 , 6×10 17 atom / cm 3 , 8×10 17 atom / cm 3 or 1×10 18 atom / cm 3 The above values ​​are not limited to the above values. Other values ​​not listed in the above values ​​also meet the requirements.

[0197] Wherein, the carrier gas used in the N-type GaN trench filling growth includes nitrogen.

[0198] The flow rate of the carrier gas used in the N-type GaN trench filling growth is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0199] Wherein, the Ga source used in the N-type GaN trench filling growth includes TMGa.

[0200] Among them, the flow rate of the Ga source used in the N-type GaN trench filling growth is 100-500sccm, for example, it can be 100sccm, 200sccm, 300sccm, 400sccm or 500sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0201] Wherein, the nitrogen source used in the N-type GaN trench filling growth includes ammonia.

[0202] The flow rate of the nitrogen source used in the N-type GaN trench filling growth is 10-50 slm, for example, 10 slm, 20 slm, 30 slm, 40 slm or 50 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0203] Wherein, the silicon source used in the N-type GaN trench filling growth includes silane.

[0204] Among them, the flow rate of the silicon source used in the N-type GaN trench filling growth is 50-100sccm, for example, it can be 50sccm, 60sccm, 70sccm, 80sccm, 90sccm or 100sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0205] Among them, the growth temperature of the N-type GaN trench filling growth is 1000-1100°C, for example, it can be 1000°C, 1020°C, 1040°C, 1060°C, 1080°C or 1100°C, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0206] Among them, the growth pressure of the N-type GaN trench filling growth is 50-600mbar, for example, it can be 50mbar, 60mbar, 80mbar, 100mbar, 200mbar, 300mbar, 400mbar, 500mbar or 600mbar, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0207] The doping concentration of the N-type GaN layer obtained by the N-type GaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 , for example, it can be 1×10 17 atom / cm 3 , 2×10 17 atom / cm 3 , 4×10 17 atom / cm 3 , 6×10 17 atom / cm 3 , 8×10 17 atom / cm 3 or 1×10 18 atom / cm 3 The above values ​​are not limited to the above values. Other values ​​not listed in the above values ​​also meet the requirements.

[0208] Among them, the thickness of the base layer obtained by growing the base layer is 5-20μm, for example, it can be 5μm, 6μm, 8μm, 10μm, 12μm, 14μm, 16μm, 18μm or 20μm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0209] Wherein, the base layer trench etching method is mask etching.

[0210] Among them, the side wall inclination angle of the groove obtained by etching the base layer groove is 86-90°, for example, it can be 86°, 87°, 88°, 89° or 90°, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0211] Among them, the depth of the grooves obtained by etching the base layer is 5-20μm, for example, it can be 5μm, 6μm, 8μm, 10μm, 12μm, 14μm, 16μm, 18μm or 20μm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0212] The width of the grooves obtained by etching the base layer grooves is 2-2.5 μm, for example, 2 μm, 2.1 μm, 2.2 μm, 2.3 μm, 2.4 μm or 2.5 μm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0213] In the present invention, if the filling height exceeds the groove depth after the groove is filled, polishing or other methods may be selected to remove the portion exceeding the groove.

[0214] Wherein, the carrier gas used in the growth of the GaN channel layer includes nitrogen.

[0215] The flow rate of the carrier gas used in the growth of the GaN channel layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0216] Wherein, the Ga source used in the growth of the GaN channel layer includes TMGa.

[0217] Among them, the flow rate of the Ga source used in the growth of the GaN channel layer is 100-200sccm, for example, it can be 100sccm, 120sccm, 140sccm, 160sccm, 180sccm or 200sccm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0218] Wherein, the nitrogen source used in the growth of the GaN channel layer includes ammonia.

[0219] The flow rate of the nitrogen source used in the growth of the GaN channel layer is 10-50 slm, for example, 10 slm, 20 slm, 30 slm, 40 slm or 50 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0220] The growth temperature of the GaN channel layer is 1100-1120°C, for example, 1100°C, 1105°C, 1110°C, 1115°C or 1120°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0221] The growth pressure of the GaN channel layer is 100-200 mbar, for example, 100 mbar, 120 mbar, 140 mbar, 160 mbar, 180 mbar or 200 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0222] The GaN channel layer grown by the GaN channel layer is 50-200nm, for example, it can be 50nm, 50nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm or 200nm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0223] Wherein, the carrier gas used in the growth of the AlN insertion layer includes nitrogen.

[0224] The flow rate of the carrier gas used in the growth of the AlN insertion layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0225] Wherein, the aluminum source used in the growth of the AlN insertion layer includes TMAl.

[0226] The flow rate of the aluminum source used in the growth of the AlN insertion layer is 40-60 sccm, for example, 40 sccm, 45 sccm, 50 sccm, 55 sccm or 60 sccm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0227] Wherein, the nitrogen source used in the growth of the AlN insertion layer includes ammonia.

[0228] The flow rate of the nitrogen source used in the growth of the AlN insertion layer is 1-5 slm, for example, 1 slm, 2 slm, 3 slm, 4 slm or 5 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0229] The growth temperature of the AlN insertion layer is 1100-1120°C, for example, 1100°C, 1105°C, 1110°C, 1115°C or 1120°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0230] The growth pressure of the AlN insertion layer is 100-200 mbar, for example, 100 mbar, 120 mbar, 140 mbar, 160 mbar, 180 mbar or 200 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0231] The thickness of the AlN insertion layer obtained by growing the AlN insertion layer is 1-1.5 nm, for example, 1 nm, 1.1 nm, 1.2 nm, 1.3 nm, 1.4 nm or 1.5 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0232] Wherein, the carrier gas used in the growth of the AlGaN barrier layer includes nitrogen.

[0233] The flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0234] Wherein, the Ga source used for growing the AlGaN barrier layer includes TMGa.

[0235] Among them, the flow rate of the Ga source used for growing the AlGaN barrier layer is 50-100sccm, for example, it can be 50sccm, 60sccm, 70sccm, 80sccm, 90sccm or 100sccm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0236] Wherein, the nitrogen source used for growing the AlGaN barrier layer includes ammonia.

[0237] The flow rate of the nitrogen source used for growing the AlGaN barrier layer is 1-5 slm, for example, 1 slm, 2 slm, 3 slm, 4 slm or 5 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0238] Wherein, the aluminum source used for growing the AlGaN barrier layer includes TMAl.

[0239] Among them, the flow rate of the aluminum source used for growing the AlGaN barrier layer is 50-200 sccm, for example, it can be 50 slm, 60 slm, 80 slm, 100 slm, 120 slm, 140 slm, 160 slm, 180 slm or 200 slm, but is not limited to the listed values, and other unlisted values ​​within the range also meet the requirements.

[0240] The growth temperature of the AlGaN barrier layer is 1100-1120°C, for example, 1100°C, 1105°C, 1110°C, 1115°C or 1120°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0241] The growth pressure of the AlGaN barrier layer is 100-200 mbar, for example, 100 mbar, 120 mbar, 140 mbar, 160 mbar, 180 mbar or 200 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0242] The thickness of the AlGaN barrier layer obtained by growing the AlGaN barrier layer is 20-30 nm, for example, 20 nm, 22 nm, 24 nm, 26 nm, 28 nm or 30 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0243] Wherein, the carrier gas used for growing the GaN cap layer includes nitrogen.

[0244] The flow rate of the carrier gas used for growing the GaN cap layer is 50-100 slm, for example, 50 slm, 60 slm, 70 slm, 80 slm, 90 slm or 100 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0245] Wherein, the Ga source used for growing the GaN cap layer includes TMGa.

[0246] Among them, the flow rate of Ga source used for growing the GaN cap layer is 30-60sccm, for example, it can be 30sccm, 35sccm, 40sccm, 45sccm, 50sccm, 55sccm or 60sccm, but is not limited to the listed values, and other unlisted values ​​within this range also meet the requirements.

[0247] Wherein, the nitrogen source used for growing the GaN cap layer includes ammonia.

[0248] The flow rate of the nitrogen source used for growing the GaN cap layer is 1-5 slm, for example, 1 slm, 2 slm, 3 slm, 4 slm or 5 slm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0249] The growth temperature of the GaN cap layer is 1110-1120°C, for example, 1100°C, 1105°C, 1110°C, 1115°C or 1120°C, but is not limited to the listed values, and other values ​​not listed in the range also meet the requirements.

[0250] The growth pressure of the GaN cap layer is 100-200 mbar, for example, 100 mbar, 120 mbar, 140 mbar, 160 mbar, 180 mbar or 200 mbar, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0251] The thickness of the GaN capping layer obtained by growing the GaN capping layer is 10-20 nm, for example, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm or 20 nm, but is not limited to the listed values, and other values ​​not listed within the range also meet the requirements.

[0252] Further, in order to illustrate the good withstand voltage performance that can be achieved by the GaN-based HEMT epitaxial wafer provided by the present invention, the following actual example is used for exemplary description, as follows:

[0253] Example 1

[0254] This embodiment provides a GaN-based HEMT epitaxial wafer, such as Figure 2 Said, including:

[0255] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0256] The nucleation layer is an AlN nucleation layer with a thickness of 18 nm;

[0257] The high resistance layer is a P-type AlGaN layer and an N-type GaN layer alternately arranged perpendicular to the setting direction of the high resistance layer; the high resistance layer is an N-type GaN layer provided with a first groove and a P-type AlGaN layer provided in the first groove; the thickness of the N-type GaN layer provided with the first groove is 10 μm; the depth of the first groove is 8 μm; the width of the first groove is 2.2 μm; the thickness of the P-type AlGaN layer provided in the first groove is equal to the depth of the first groove;

[0258] The channel layer is a GaN channel layer with a thickness of 100 nm;

[0259] The insertion layer is an AlN insertion layer with a thickness of 1.2 nm;

[0260] The barrier layer is an AlGaN barrier layer with a thickness of 25 nm;

[0261] The capping layer is a GaN capping layer with a thickness of 15 nm.

[0262] The preparation process is as follows:

[0263] The AlN nucleation layer, the P-type AlGaN-N-type GaN high resistance layer, the GaN channel layer, the AlN insertion layer, the AlGaN barrier layer and the GaN cap layer are sequentially grown on the substrate to obtain a GaN-based HEMT epitaxial wafer;

[0264] The growth temperature of the AlN nucleation layer is 800° C.; the growth pressure of the AlN nucleation layer is 150 mbr;

[0265] The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence;

[0266] When the base layer growth is an N-type GaN layer growth, the trench filling growth is a P-type AlGaN trench filling growth;

[0267] The carrier gas used in the growth of the N-type GaN layer is nitrogen; the flow rate of the carrier gas used in the growth of the N-type GaN layer is 60 slm; the Ga source used in the growth of the N-type GaN layer is TMGa; the flow rate of the Ga source used in the growth of the N-type GaN layer is 200 sccm; the nitrogen source used in the growth of the N-type GaN layer is ammonia; the flow rate of the nitrogen source used in the growth of the N-type GaN layer is 20 slm; the silicon source used in the growth of the N-type GaN layer is silane; the flow rate of the silicon source used in the growth of the N-type GaN layer is 80 sccm; the growth temperature in the growth of the N-type GaN layer is 1050°C; the growth pressure in the growth of the N-type GaN layer is 300 mbar; the doping concentration of the N-type GaN layer obtained by the growth of the N-type GaN layer is 4×1017 atom / cm 3 ;

[0268] The carrier gas used in the P-type AlGaN trench filling growth is nitrogen; the flow rate of the carrier gas used in the P-type AlGaN trench filling growth is 60 slm; the Ga source used in the P-type AlGaN trench filling growth is TMGa; the flow rate of the Ga source used in the P-type AlGaN trench filling growth is 300 sccm; the nitrogen source used in the P-type AlGaN trench filling growth is ammonia; the flow rate of the nitrogen source used in the P-type AlGaN trench filling growth is 30 slm; the aluminum source used in the P-type AlGaN trench filling growth is TMAl; the flow rate of the aluminum source used in the P-type AlGaN trench filling growth is 100 sccm; the growth temperature of the P-type AlGaN trench filling growth is 1050°C; the growth pressure of the P-type AlGaN trench filling growth is 400 mbar; the doping concentration of the P-type AlGaN layer obtained by the P-type AlGaN trench filling growth is 4×10 17 atom / cm 3 ;

[0269] The base layer groove is etched by mask etching; the side wall inclination angle of the groove obtained by etching the base layer groove is 88°;

[0270] The carrier gas used in the growth of the GaN channel layer is nitrogen; the flow rate of the carrier gas used in the growth of the GaN channel layer is 60 slm; the Ga source used in the growth of the GaN channel layer is TMGa; the flow rate of the Ga source used in the growth of the GaN channel layer is 150 sccm; the nitrogen source used in the growth of the GaN channel layer is ammonia; the flow rate of the nitrogen source used in the growth of the GaN channel layer is 30 slm; the growth temperature of the GaN channel layer is 1110°C; the growth pressure of the GaN channel layer is 150 mbar; the GaN channel layer obtained by the growth of the GaN channel layer is 100 nm;

[0271] The carrier gas used in the growth of the AlN insertion layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlN insertion layer is 60 slm; the aluminum source used in the growth of the AlN insertion layer is TMAl; the flow rate of the aluminum source used in the growth of the AlN insertion layer is 50 sccm; the nitrogen source used in the growth of the AlN insertion layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 2 slm; the growth temperature of the AlN insertion layer is 1110°C; the growth pressure of the AlN insertion layer is 150 mbar;

[0272] The carrier gas used in the growth of the AlGaN barrier layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 60 slm; the Ga source used in the growth of the AlGaN barrier layer is TMGa; the flow rate of the Ga source used in the growth of the AlGaN barrier layer is 60 sccm; the nitrogen source used in the growth of the AlGaN barrier layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlGaN barrier layer is 2 slm; the aluminum source used in the growth of the AlGaN barrier layer is TMAl; the flow rate of the aluminum source used in the growth of the AlGaN barrier layer is 100 sccm; the growth temperature of the AlGaN barrier layer is 1110°C; the growth pressure of the AlGaN barrier layer is 150 mbar;

[0273] The carrier gas used for the growth of the GaN cap layer is nitrogen; the flow rate of the carrier gas used for the growth of the GaN cap layer is 60slm; the Ga source used for the growth of the GaN cap layer is TMGa; the flow rate of the Ga source used for the growth of the GaN cap layer is 40sccm; the nitrogen source used for the growth of the GaN cap layer is ammonia; the flow rate of the nitrogen source used for the growth of the GaN cap layer is 2slm; the growth temperature of the GaN cap layer is 1114°C; the growth pressure of the GaN cap layer is 150mbar.

[0274] Example 2

[0275] This embodiment provides a GaN-based HEMT epitaxial wafer, such as Figure 3 As shown, including:

[0276] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0277] The nucleation layer is an AlN nucleation layer with a thickness of 17 nm;

[0278] The high resistance layer is a P-type AlGaN layer and an N-type GaN layer alternately arranged perpendicular to the setting direction of the high resistance layer; the high resistance layer is a P-type AlGaN layer provided with a second groove and an N-type GaN layer provided in the second groove; the thickness of the P-type AlGaN layer provided with the second groove is 15 μm; the depth of the second groove is 10 μm; the width of the second groove is 2.4 μm; the thickness of the N-type GaN layer provided in the second groove is equal to the depth of the second groove;

[0279] The channel layer is a GaN channel layer with a thickness of 150 nm;

[0280] The insertion layer is an AlN insertion layer with a thickness of 1.4 nm;

[0281] The barrier layer is an AlGaN barrier layer with a thickness of 28 nm;

[0282] The capping layer is a GaN capping layer with a thickness of 18 nm.

[0283] The preparation process is as follows:

[0284] The AlN nucleation layer, the P-type AlGaN-N-type GaN high resistance layer, the GaN channel layer, the AlN insertion layer, the AlGaN barrier layer and the GaN cap layer are sequentially grown on the substrate to obtain a GaN-based HEMT epitaxial wafer;

[0285] The growth temperature of the AlN nucleation layer is 1000° C.; the growth pressure of the AlN nucleation layer is 100 mbr;

[0286] The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence;

[0287] When the base layer growth is a P-type AlGaN layer growth, the trench filling growth is an N-type GaN trench filling growth;

[0288] The carrier gas used in the growth of the P-type AlGaN layer is nitrogen; the flow rate of the carrier gas used in the growth of the P-type AlGaN layer is 80 slm; the Ga source used in the growth of the P-type AlGaN layer is TMGa; the flow rate of the Ga source used in the growth of the P-type AlGaN layer is 300 sccm; the nitrogen source used in the growth of the P-type AlGaN layer is ammonia; the flow rate of the nitrogen source used in the growth of the P-type AlGaN layer is 30 slm; the aluminum source used in the growth of the P-type AlGaN layer is TMAl; the flow rate of the aluminum source used in the growth of the P-type AlGaN layer is 100 sccm; the growth temperature of the P-type AlGaN layer is 1080°C; the growth pressure of the P-type AlGaN layer is 400 mbar; the doping concentration of the P-type AlGaN layer obtained by the growth of the P-type AlGaN layer is 7×10 17 atom / cm 3 ;

[0289] The carrier gas used in the N-type GaN trench filling growth is nitrogen; the flow rate of the carrier gas used in the N-type GaN trench filling growth is 80 slm; the Ga source used in the N-type GaN trench filling growth is TMGa; the flow rate of the Ga source used in the N-type GaN trench filling growth is 400 sccm; the nitrogen source used in the N-type GaN trench filling growth is ammonia; the flow rate of the nitrogen source used in the N-type GaN trench filling growth is 40 slm; the silicon source used in the N-type GaN trench filling growth is silane; the flow rate of the silicon source used in the N-type GaN trench filling growth is 80 sccm; the growth temperature of the N-type GaN trench filling growth is 1080°C; the growth pressure of the N-type GaN trench filling growth is 300 mbar; the doping concentration of the N-type GaN layer obtained by the N-type GaN trench filling growth is 7×10 17 atom / cm 3 ;

[0290] The method of etching the base layer groove is mask etching, and the side wall inclination angle of the groove obtained by etching the base layer groove is 87°;

[0291] The carrier gas used in the growth of the GaN channel layer is nitrogen; the flow rate of the carrier gas used in the growth of the GaN channel layer is 80 slm; the Ga source used in the growth of the GaN channel layer is TMGa; the flow rate of the Ga source used in the growth of the GaN channel layer is 180 sccm; the nitrogen source used in the growth of the GaN channel layer is ammonia; the flow rate of the nitrogen source used in the growth of the GaN channel layer is 40 slm; the growth temperature of the GaN channel layer is 1115°C; the growth pressure of the GaN channel layer is 180 mbar; the GaN channel layer obtained by the growth of the GaN channel layer is 150 nm;

[0292] The carrier gas used in the growth of the AlN insertion layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlN insertion layer is 80 slm; the aluminum source used in the growth of the AlN insertion layer is TMAl; the flow rate of the aluminum source used in the growth of the AlN insertion layer is 55 sccm; the nitrogen source used in the growth of the AlN insertion layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 3 slm; the growth temperature of the AlN insertion layer is 1115°C; the growth pressure of the AlN insertion layer is 180 mbar;

[0293] The carrier gas used in the growth of the AlGaN barrier layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 80 slm; the Ga source used in the growth of the AlGaN barrier layer is TMGa; the flow rate of the Ga source used in the growth of the AlGaN barrier layer is 80 sccm; the nitrogen source used in the growth of the AlGaN barrier layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlGaN barrier layer is 3 slm; the aluminum source used in the growth of the AlGaN barrier layer is TMAl; the flow rate of the aluminum source used in the growth of the AlGaN barrier layer is 150 sccm; the growth temperature of the AlGaN barrier layer is 1115°C; the growth pressure of the AlGaN barrier layer is 180 mbar;

[0294] The carrier gas used for the growth of the GaN cap layer is nitrogen; the flow rate of the carrier gas used for the growth of the GaN cap layer is 80slm; the Ga source used for the growth of the GaN cap layer is TMGa; the flow rate of the Ga source used for the growth of the GaN cap layer is 50sccm; the nitrogen source used for the growth of the GaN cap layer is ammonia; the flow rate of the nitrogen source used for the growth of the GaN cap layer is 3slm; the growth temperature of the GaN cap layer is 1117°C; the growth pressure of the GaN cap layer is 180mbar.

[0295] Example 3

[0296] This embodiment provides a GaN-based HEMT epitaxial wafer, such as Figure 4 Said, including:

[0297] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0298] The nucleation layer is an AlN nucleation layer with a thickness of 15 nm;

[0299] The high resistance layer is a P-type AlGaN layer and an N-type GaN layer alternately arranged perpendicular to the setting direction of the high resistance layer; the high resistance layer is an N-type GaN layer provided with a first groove and a P-type AlGaN layer provided in the first groove; the thickness of the N-type GaN layer provided with the first groove is 5 μm; the depth of the first groove is 5 μm; the width of the first groove is 2 μm; the thickness of the P-type AlGaN layer provided in the first groove is equal to the depth of the first groove;

[0300] The channel layer is a GaN channel layer with a thickness of 50 nm;

[0301] The insertion layer is an AlN insertion layer with a thickness of 1.5 nm;

[0302] The barrier layer is an AlGaN barrier layer with a thickness of 20 nm;

[0303] The capping layer is a GaN capping layer with a thickness of 20 nm.

[0304] The preparation process is as follows:

[0305] The AlN nucleation layer, the P-type AlGaN-N-type GaN high resistance layer, the GaN channel layer, the AlN insertion layer, the AlGaN barrier layer and the GaN cap layer are sequentially grown on the substrate to obtain a GaN-based HEMT epitaxial wafer;

[0306] The growth temperature of the AlN nucleation layer is 600° C.; the growth pressure of the AlN nucleation layer is 200 mbr;

[0307] The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence;

[0308] When the base layer growth is an N-type GaN layer growth, the trench filling growth is a P-type AlGaN trench filling growth;

[0309] The carrier gas used in the growth of the N-type GaN layer is nitrogen; the flow rate of the carrier gas used in the growth of the N-type GaN layer is 50 slm; the Ga source used in the growth of the N-type GaN layer is TMGa; the flow rate of the Ga source used in the growth of the N-type GaN layer is 100 sccm; the nitrogen source used in the growth of the N-type GaN layer is ammonia; the flow rate of the nitrogen source used in the growth of the N-type GaN layer is 10 slm; the silicon source used in the growth of the N-type GaN layer is silane; the flow rate of the silicon source used in the growth of the N-type GaN layer is 50 sccm; the growth temperature in the growth of the N-type GaN layer is 1000°C; the growth pressure in the growth of the N-type GaN layer is 50 mbar; the doping concentration of the N-type GaN layer obtained by the growth of the N-type GaN layer is 1×10 17 atom / cm 3 ;

[0310] The carrier gas used in the P-type AlGaN trench filling growth is nitrogen; the flow rate of the carrier gas used in the P-type AlGaN trench filling growth is 50 slm; the Ga source used in the P-type AlGaN trench filling growth is TMGa; the flow rate of the Ga source used in the P-type AlGaN trench filling growth is 100 sccm; the nitrogen source used in the P-type AlGaN trench filling growth is ammonia; the flow rate of the nitrogen source used in the P-type AlGaN trench filling growth is 10 slm; the aluminum source used in the P-type AlGaN trench filling growth is TMAl; the flow rate of the aluminum source used in the P-type AlGaN trench filling growth is 50 sccm; the growth temperature of the P-type AlGaN trench filling growth is 1000°C; the growth pressure of the P-type AlGaN trench filling growth is 500 mbar; the doping concentration of the P-type AlGaN layer obtained by the P-type AlGaN trench filling growth is 1×10 17 atom / cm 3 ;

[0311] The base layer groove is etched by mask etching; the side wall inclination angle of the groove obtained by etching the base layer groove is 86°;

[0312] The carrier gas used in the growth of the GaN channel layer is nitrogen; the flow rate of the carrier gas used in the growth of the GaN channel layer is 50 slm; the Ga source used in the growth of the GaN channel layer is TMGa; the flow rate of the Ga source used in the growth of the GaN channel layer is 100 sccm; the nitrogen source used in the growth of the GaN channel layer is ammonia; the flow rate of the nitrogen source used in the growth of the GaN channel layer is 10 slm; the growth temperature of the GaN channel layer is 1100°C; the growth pressure of the GaN channel layer is 100 mbar;

[0313] The carrier gas used in the growth of the AlN insertion layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlN insertion layer is 50 slm; the aluminum source used in the growth of the AlN insertion layer is TMAl; the flow rate of the aluminum source used in the growth of the AlN insertion layer is 40 sccm; the nitrogen source used in the growth of the AlN insertion layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 1 slm; the growth temperature of the AlN insertion layer is 1100°C; the growth pressure of the AlN insertion layer is 100 mbar;

[0314] The carrier gas used in the growth of the AlGaN barrier layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 50 slm; the Ga source used in the growth of the AlGaN barrier layer is TMGa; the flow rate of the Ga source used in the growth of the AlGaN barrier layer is 50 sccm; the nitrogen source used in the growth of the AlGaN barrier layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlGaN barrier layer is 1 slm; the aluminum source used in the growth of the AlGaN barrier layer is TMAl; the flow rate of the aluminum source used in the growth of the AlGaN barrier layer is 50 sccm; the growth temperature of the AlGaN barrier layer is 1100°C; the growth pressure of the AlGaN barrier layer is 100 mbar;

[0315] The carrier gas used for the growth of the GaN cap layer is nitrogen; the flow rate of the carrier gas used for the growth of the GaN cap layer is 50slm; the Ga source used for the growth of the GaN cap layer is TMGa; the flow rate of the Ga source used for the growth of the GaN cap layer is 30sccm; the nitrogen source used for the growth of the GaN cap layer is ammonia; the flow rate of the nitrogen source used for the growth of the GaN cap layer is 1slm; the growth temperature of the GaN cap layer is 1110°C; the growth pressure of the GaN cap layer is 100mbar.

[0316] Example 4

[0317] This embodiment provides a GaN-based HEMT epitaxial wafer, such as Figure 5 As shown, including:

[0318] A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top;

[0319] The nucleation layer is an AlN nucleation layer with a thickness of 20 nm;

[0320] The high resistance layer is a P-type AlGaN layer and an N-type GaN layer alternately arranged perpendicular to the setting direction of the high resistance layer; the high resistance layer is a P-type AlGaN layer provided with a second groove and an N-type GaN layer provided in the second groove; the thickness of the P-type AlGaN layer provided with the second groove is 20 μm; the depth of the second groove is 20 μm; the width of the second groove is 2.5 μm; the thickness of the N-type GaN layer provided in the second groove is equal to the depth of the second groove;

[0321] The channel layer is a GaN channel layer with a thickness of 200 nm;

[0322] The insertion layer is an AlN insertion layer with a thickness of 1 nm;

[0323] The barrier layer is an AlGaN barrier layer with a thickness of 30 nm;

[0324] The capping layer is a GaN capping layer with a thickness of 10 nm.

[0325] The preparation process is as follows:

[0326] The AlN nucleation layer, the P-type AlGaN-N-type GaN high resistance layer, the GaN channel layer, the AlN insertion layer, the AlGaN barrier layer and the GaN cap layer are sequentially grown on the substrate to obtain a GaN-based HEMT epitaxial wafer;

[0327] The growth temperature of the AlN nucleation layer is 1200° C.; the growth pressure of the AlN nucleation layer is 50 mbr;

[0328] The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer trench etching and trench filling growth performed in sequence;

[0329] When the base layer growth is a P-type AlGaN layer growth, the trench filling growth is an N-type GaN trench filling growth;

[0330] The carrier gas used in the growth of the P-type AlGaN layer is nitrogen; the flow rate of the carrier gas used in the growth of the P-type AlGaN layer is 100 slm; the Ga source used in the growth of the P-type AlGaN layer is TMGa; the flow rate of the Ga source used in the growth of the P-type AlGaN layer is 500 sccm; the nitrogen source used in the growth of the P-type AlGaN layer is ammonia; the flow rate of the nitrogen source used in the growth of the P-type AlGaN layer is 50 slm; the aluminum source used in the growth of the P-type AlGaN layer is TMAl; the flow rate of the aluminum source used in the growth of the P-type AlGaN layer is 200 sccm; the growth temperature of the P-type AlGaN layer is 1100°C; the growth pressure of the P-type AlGaN layer is 500 mbar; the doping concentration of the P-type AlGaN layer obtained by the growth of the P-type AlGaN layer is 1×10 18 atom / cm 3 ;

[0331] The carrier gas used in the N-type GaN trench filling growth is nitrogen; the flow rate of the carrier gas used in the N-type GaN trench filling growth is 100 slm; the Ga source used in the N-type GaN trench filling growth is TMGa; the flow rate of the Ga source used in the N-type GaN trench filling growth is 500 sccm; the nitrogen source used in the N-type GaN trench filling growth is ammonia; the flow rate of the nitrogen source used in the N-type GaN trench filling growth is 50 slm; the silicon source used in the N-type GaN trench filling growth is silane; the flow rate of the silicon source used in the N-type GaN trench filling growth is 100 sccm; the growth temperature of the N-type GaN trench filling growth is 1100°C; the growth pressure of the N-type GaN trench filling growth is 50 mbar; the doping concentration of the N-type GaN layer obtained by the N-type GaN trench filling growth is 1×10 18 atom / cm 3 ;

[0332] The method of etching the base layer groove is mask etching, and the side wall inclination angle of the groove obtained by etching the base layer groove is 90°;

[0333] The carrier gas used in the growth of the GaN channel layer is nitrogen; the flow rate of the carrier gas used in the growth of the GaN channel layer is 100 slm; the Ga source used in the growth of the GaN channel layer is TMGa; the flow rate of the Ga source used in the growth of the GaN channel layer is 200 sccm; the nitrogen source used in the growth of the GaN channel layer is ammonia; the flow rate of the nitrogen source used in the growth of the GaN channel layer is 50 slm; the growth temperature of the GaN channel layer is 1120°C; the growth pressure of the GaN channel layer is 200 mbar;

[0334] The carrier gas used in the growth of the AlN insertion layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlN insertion layer is 100 slm; the aluminum source used in the growth of the AlN insertion layer is TMAl; the flow rate of the aluminum source used in the growth of the AlN insertion layer is 60 sccm; the nitrogen source used in the growth of the AlN insertion layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 5 slm; the growth temperature of the AlN insertion layer is 1120°C; the growth pressure of the AlN insertion layer is 200 mbar;

[0335] The carrier gas used in the growth of the AlGaN barrier layer is nitrogen; the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 100 slm; the Ga source used in the growth of the AlGaN barrier layer is TMGa; the flow rate of the Ga source used in the growth of the AlGaN barrier layer is 100 sccm; the nitrogen source used in the growth of the AlGaN barrier layer is ammonia; the flow rate of the nitrogen source used in the growth of the AlGaN barrier layer is 5 slm; the aluminum source used in the growth of the AlGaN barrier layer is TMAl; the flow rate of the aluminum source used in the growth of the AlGaN barrier layer is 200 sccm; the growth temperature of the AlGaN barrier layer is 1120°C; the growth pressure of the AlGaN barrier layer is 200 mbar;

[0336] The carrier gas used for the growth of the GaN cap layer is nitrogen; the flow rate of the carrier gas used for the growth of the GaN cap layer is 100slm; the Ga source used for the growth of the GaN cap layer is TMGa; the flow rate of the Ga source used for the growth of the GaN cap layer is 60sccm; the nitrogen source used for the growth of the GaN cap layer is ammonia; the flow rate of the nitrogen source used for the growth of the GaN cap layer is 5slm; the growth temperature of the GaN cap layer is 1120°C; the growth pressure of the GaN cap layer is 200mbar.

[0337] Example 5

[0338] The only difference from Embodiment 1 is that the thickness of the N-type GaN layer provided with the first groove is 2 μm.

[0339] Example 6

[0340] The only difference from Embodiment 1 is that the thickness of the N-type GaN layer provided with the first groove is 30 μm.

[0341] Comparative Example 1

[0342] The only difference from Embodiment 1 is that the P-type AlGaN layer in the high resistance layer is replaced by an N-type AlGaN layer.

[0343] Comparative Example 2

[0344] The only difference from Example 1 is that the N-type GaN layer in the high resistance layer is replaced by a P-type GaN layer.

[0345] Comparative Example 3

[0346] The only difference from Example 1 is that the N-type GaN layer in the high resistance layer is replaced by a GaN layer.

[0347] Comparative Example 4

[0348] The only difference from Embodiment 1 is that the P-type AlGaN layer in the high resistance layer is replaced by an AlGaN layer.

[0349] Comparative Example 5

[0350] The only difference from Embodiment 1 is that the high resistance layer is an N-type AlGaN layer and a P-type GaN layer which are alternately arranged perpendicular to the arrangement direction of the high resistance layer.

[0351] Comparative Example 6

[0352] The only difference from Example 1 is that the high resistance layer is a P-type AlGaN layer and an N-type GaN layer stacked from bottom to top, and the thickness of the single-layer P-type AlGaN layer and the N-type GaN layer are both 2.5 μm.

[0353] The GaN-based HEMT epitaxial wafers obtained in the embodiment and the comparative example were tested for crystal quality using a high-resolution X-ray diffractometer (HRXRD), and the voltage resistance was tested using the T / CASAS 028—2023Sub-6GHz GaN RF device reliability screening and acceptance method. The results are shown in Table 1 below.

[0354] Table 1

[0355] 002 Full width at half maximum (FWHM) 102 Full width at half maximum (FWHM) <![CDATA[Vertical breakdown voltage ~ 850V @ 1μA / mm 2 > Example 1 295 696 1109 Example 2 306 703 1128 Example 3 290 701 1168 Example 4 302 707 1126 Example 5 524 956 903 Example 6 540 986 934 Comparative Example 1 673 1034 760 Comparative Example 2 734 1124 742 Comparative Example 3 683 1078 756 Comparative Example 4 652 1098 762 Comparative Example 5 745 1135 734 Comparative Example 6 694 1146 784

[0356] As can be seen from Table 1, the GaN-based HEMT epitaxial wafer provided by the present invention obtains a high-resistance layer with high crystal growth quality by designing a specific high-resistance layer and utilizing a high-resistance layer with a specific structure and composition, which is beneficial to avoiding leakage and thus improving the voltage resistance performance of the device.

[0357] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0358] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0359] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A GaN-based HEMT epitaxial wafer, characterized in that: The GaN-based HEMT epitaxial wafer comprises: A substrate, and a nucleation layer, a high resistance layer, a channel layer, an insertion layer, a barrier layer and a cap layer sequentially arranged on the substrate from bottom to top; The high resistance layer comprises a P-type AlGaN layer and an N-type GaN layer which are alternately arranged perpendicular to the arrangement direction of the high resistance layer.

2. The GaN-based HEMT epitaxial wafer according to claim 1, characterized in that: The nucleation layer is an AlN nucleation layer with a thickness of 15-20 nm.

3. The GaN-based HEMT epitaxial wafer according to claim 1 or 2, characterized in that: The high resistance layer is an N-type GaN layer provided with a first groove and a P-type AlGaN layer provided in the first groove; Or, the high resistance layer is a P-type AlGaN layer provided with a second groove and an N-type GaN layer provided in the second groove; Preferably, the thickness of the N-type GaN layer provided with the first groove is 5-20 μm; Preferably, the depth of the first groove is 5-20 μm; Preferably, the width of the first groove is 2-2.5 μm; Preferably, the thickness of the P-type AlGaN layer disposed in the first groove is equal to the depth of the first groove; Preferably, the thickness of the P-type AlGaN layer provided with the second groove is 5-20 μm; Preferably, the depth of the second groove is 5-20 μm; Preferably, the width of the second groove is 2-2.5 μm; Preferably, the thickness of the N-type GaN layer disposed in the second groove is equal to the depth of the second groove.

4. The GaN-based HEMT epitaxial wafer according to any one of claims 1 to 3, characterized in that: The channel layer is a GaN channel layer with a thickness of 50-200 nm; Preferably, the insertion layer is an AlN insertion layer with a thickness of 1-1.5 nm; Preferably, the barrier layer is an AlGaN barrier layer with a thickness of 20-30 nm; Preferably, the capping layer is a GaN capping layer with a thickness of 10-20 nm.

5. A method for preparing a GaN-based HEMT epitaxial wafer according to any one of claims 1 to 4, characterized in that: The preparation method comprises: The AlN nucleation layer growth, the P-type AlGaN-N-type GaN high resistance layer growth, the GaN channel layer growth, the AlN insertion layer growth, the AlGaN barrier layer growth and the GaN cap layer growth are sequentially performed on the substrate to obtain a GaN-based HEMT epitaxial wafer.

6. The preparation method according to claim 5, characterized in that: The growth temperature of the AlN nucleation layer is 600-1200° C. Preferably, the growth pressure of the AlN nucleation layer is 50-200 mbr; Preferably, the thickness of the AlN nucleation layer obtained by growing the AlN nucleation layer is 15-20 nm.

7. The preparation method according to claim 5 or 6, characterized in that: The growth of the P-type AlGaN-N-type GaN high resistance layer includes base layer growth, base layer groove etching and groove filling growth performed in sequence; Preferably, the base layer growth includes N-type GaN layer growth or P-type AlGaN layer growth; Preferably, when the base layer growth is N-type GaN layer growth, the trench filling growth is P-type AlGaN trench filling growth; Preferably, the carrier gas used in the growth of the N-type GaN layer includes nitrogen; Preferably, the flow rate of the carrier gas used in the growth of the N-type GaN layer is 50-100 slm; Preferably, the Ga source used in the growth of the N-type GaN layer includes TMGa; Preferably, the flow rate of the Ga source used in the growth of the N-type GaN layer is 100-500 sccm; Preferably, the nitrogen source used in the growth of the N-type GaN layer includes ammonia; Preferably, the flow rate of the nitrogen source used in the growth of the N-type GaN layer is 10-50 slm; Preferably, the silicon source used in the growth of the N-type GaN layer includes silane; Preferably, the flow rate of the silicon source used in the growth of the N-type GaN layer is 50-100 sccm; Preferably, the growth temperature of the N-type GaN layer is 1000-1100° C.; Preferably, the growth pressure during the growth of the N-type GaN layer is 50-600 mbar; Preferably, the doping concentration of the N-type GaN layer obtained by growing the N-type GaN layer is 1×10 17 -1×10 18 atom / cm 3 ; Preferably, the carrier gas used in the P-type AlGaN trench filling growth includes nitrogen; Preferably, the flow rate of the carrier gas used in the P-type AlGaN trench filling growth is 50-100 slm; Preferably, the Ga source used in the P-type AlGaN trench filling growth includes TMGa; Preferably, the flow rate of the Ga source used in the P-type AlGaN trench filling growth is 100-500 sccm; Preferably, the nitrogen source used in the P-type AlGaN trench filling growth includes ammonia; Preferably, the flow rate of the nitrogen source used in the P-type AlGaN trench filling growth is 10-50slm; Preferably, the aluminum source used in the P-type AlGaN trench filling growth comprises TMAl; Preferably, the flow rate of the aluminum source used in the P-type AlGaN trench filling growth is 50-200 sccm; Preferably, the growth temperature of the P-type AlGaN trench filling growth is 1000-1100° C.; Preferably, the growth pressure of the P-type AlGaN trench filling growth is 300-500 mbar; Preferably, the doping concentration of the P-type AlGaN layer obtained by the P-type AlGaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 ; Preferably, when the base layer growth is a P-type AlGaN layer growth, the trench filling growth is an N-type GaN trench filling growth; Preferably, the carrier gas used in the growth of the P-type AlGaN layer includes nitrogen; Preferably, the flow rate of the carrier gas used in the growth of the P-type AlGaN layer is 50-100 slm; Preferably, the Ga source used in the growth of the P-type AlGaN layer includes TMGa; Preferably, the flow rate of the Ga source used in the growth of the P-type AlGaN layer is 100-500 sccm; Preferably, the nitrogen source used in the growth of the P-type AlGaN layer includes ammonia; Preferably, the flow rate of the nitrogen source used in the growth of the P-type AlGaN layer is 10-50 slm; Preferably, the aluminum source used in the growth of the P-type AlGaN layer includes TMAl; Preferably, the flow rate of the aluminum source used in the growth of the P-type AlGaN layer is 50-200 sccm; Preferably, the growth temperature of the P-type AlGaN layer is 1000-1100° C.; Preferably, the growth pressure of the P-type AlGaN layer is 300-500 mbar; Preferably, the doping concentration of the P-type AlGaN layer obtained by growing the P-type AlGaN layer is 1×10 17 -1×10 18 atom / cm 3 ; Preferably, the carrier gas used in the N-type GaN trench filling growth includes nitrogen; Preferably, the flow rate of the carrier gas used in the N-type GaN trench filling growth is 50-100 slm; Preferably, the Ga source used in the N-type GaN trench filling growth includes TMGa; Preferably, the flow rate of the Ga source used in the N-type GaN trench filling growth is 100-500 sccm; Preferably, the nitrogen source used in the N-type GaN trench filling growth includes ammonia; Preferably, the flow rate of the nitrogen source used in the N-type GaN trench filling growth is 10-50slm; Preferably, the silicon source used in the N-type GaN trench filling growth comprises silane; Preferably, the flow rate of the silicon source used in the N-type GaN trench filling growth is 50-100 sccm; Preferably, the growth temperature of the N-type GaN trench filling growth is 1000-1100° C.; Preferably, the growth pressure of the N-type GaN trench filling growth is 50-600 mbar; Preferably, the doping concentration of the N-type GaN layer obtained by the N-type GaN trench filling growth is 1×10 17 -1×10 18 atom / cm 3 ; Preferably, the thickness of the base layer obtained by growing the base layer is 5-20 μm; Preferably, the base layer groove etching method is mask etching; Preferably, the sidewall inclination angle of the groove obtained by etching the base layer groove is 86-90°; Preferably, the depth of the grooves obtained by etching the base layer grooves is 5-20 μm; Preferably, the width of the grooves obtained by etching the base layer grooves is 2-2.5 μm.

8. The preparation method according to any one of claims 5 to 7, characterized in that: The carrier gas used in the growth of the GaN channel layer includes nitrogen; Preferably, the flow rate of the carrier gas used in the growth of the GaN channel layer is 50-100 slm; Preferably, the Ga source used in the growth of the GaN channel layer includes TMGa; Preferably, the flow rate of the Ga source used in the growth of the GaN channel layer is 100-200 sccm; Preferably, the nitrogen source used in the growth of the GaN channel layer includes ammonia; Preferably, the flow rate of the nitrogen source used in the growth of the GaN channel layer is 10-50 slm; Preferably, the growth temperature of the GaN channel layer is 1100-1120°C; Preferably, the growth pressure of the GaN channel layer is 100-200 mbar; Preferably, the GaN channel layer grown by the GaN channel layer is 50-200nm; Preferably, the carrier gas used in the growth of the AlN insertion layer includes nitrogen; Preferably, the flow rate of the carrier gas used in the growth of the AlN insertion layer is 50-100 slm; Preferably, the aluminum source used in the growth of the AlN insertion layer comprises TMAl; Preferably, the flow rate of the aluminum source used in the growth of the AlN insertion layer is 40-60 sccm; Preferably, the nitrogen source used in the growth of the AlN insertion layer includes ammonia; Preferably, the flow rate of the nitrogen source used in the growth of the AlN insertion layer is 1-5 slm; Preferably, the growth temperature of the AlN insertion layer is 1100-1120°C; Preferably, the growth pressure of the AlN insertion layer is 100-200 mbar; Preferably, the thickness of the AlN insertion layer obtained by growing the AlN insertion layer is 1-1.5 nm.

9. The preparation method according to any one of claims 5 to 8, characterized in that: The carrier gas used in the growth of the AlGaN barrier layer includes nitrogen; Preferably, the flow rate of the carrier gas used in the growth of the AlGaN barrier layer is 50-100 slm; Preferably, the Ga source used for growing the AlGaN barrier layer includes TMGa; Preferably, the flow rate of the Ga source used for growing the AlGaN barrier layer is 50-100 sccm; Preferably, the nitrogen source used for growing the AlGaN barrier layer includes ammonia; Preferably, the flow rate of the nitrogen source used for growing the AlGaN barrier layer is 1-5 slm; Preferably, the aluminum source used for growing the AlGaN barrier layer includes TMAl; Preferably, the flow rate of the aluminum source used for growing the AlGaN barrier layer is 50-200 sccm; Preferably, the growth temperature of the AlGaN barrier layer is 1100-1120°C; Preferably, the growth pressure of the AlGaN barrier layer is 100-200 mbar; Preferably, the thickness of the AlGaN barrier layer obtained by growing the AlGaN barrier layer is 20-30 nm; Preferably, the carrier gas used for growing the GaN cap layer includes nitrogen; Preferably, the flow rate of the carrier gas used for growing the GaN cap layer is 50-100 slm; Preferably, the Ga source used for growing the GaN cap layer includes TMGa; Preferably, the flow rate of Ga source used for growing the GaN cap layer is 30-60 sccm; Preferably, the nitrogen source used for growing the GaN cap layer includes ammonia; Preferably, the flow rate of the nitrogen source used for growing the GaN cap layer is 1-5 slm; Preferably, the growth temperature of the GaN capping layer is 1110-1120° C.; Preferably, the growth pressure of the GaN capping layer is 100-200 mbar; Preferably, the thickness of the GaN capping layer obtained by growing the GaN capping layer is 10-20 nm.

10. A use of the GaN-based HEMT epitaxial wafer according to any one of claims 1 to 5, characterized in that: The uses include: The GaN-based HEMT epitaxial wafer is used to prepare a power device.

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