Algan / gan-based 35ghz millimeter wave rectifier and preparation method and application thereof

Abstract

This invention discloses an AlGaN / GaN-based 35GHz millimeter-wave rectifier, its fabrication method, and its application. The structure, from bottom to top, consists of an Al substrate, undoped Al... x Ga 1‑x The system includes an N-layer and an undoped GaN layer, and further comprises a mesa-shaped isolation groove and a Schottky contact electrode; the bottom of the mesa-shaped isolation groove is located at the undoped Al layer. x Ga 1‑x The N-layer has one side in contact with the undoped GaN layer and the other side in contact with the Schottky contact electrode. A layer of SiN is deposited on the inner surface of the mesa isolation groove. y Passivation layer; the bottom of the Schottky contact electrode is located on undoped Al. x Ga 1‑x The N-layer has one side in contact with the isolation groove on the platform, and the other side is the side of the rectifier. The rectifier obtained by this invention can be grown at room temperature, reducing energy consumption, with low target material cost, and can be mass-produced.

Description

Technical Field

[0001] This invention belongs to the field of rectifier technology, specifically relating to an AlGaN / GaN-based 35GHz millimeter-wave rectifier, its fabrication method, and its application. Background Technology

[0002] 35GHz millimeter-wave rectifiers are an essential component of space wireless power transmission systems, finding wide application in military and civilian fields such as satellite systems, aerospace vehicles, and home appliances. GaN, as a third-generation semiconductor, possesses characteristics such as high breakdown voltage, large bandgap, high thermal conductivity, high electron saturation velocity, and high carrier mobility, making it a promising candidate for 35GHz millimeter-wave rectifier fabrication. At high frequencies, heat dissipation capacity significantly impacts rectifier performance. Al has a high thermal conductivity of 237 W / mK and a very small lattice mismatch with AlGaN / GaN epitaxial layers, making it an ideal substrate for AlGaN / GaN 35GHz millimeter-wave rectifiers. Currently, AlGaN growth on Al substrates using the PLD method mostly employs pulsed laser ablation of the GaN target, where the Al substrate is heated and Al plasma escapes, thus synthesizing AlGaN; or directly using laser ablation of the AlGaN target. However, the former cannot be grown at room temperature, thus limiting the quality of AlGaN / GaN heterojunctions and increasing energy consumption; while the latter cannot be mass-produced due to the high cost of AlGaN targets. Therefore, exploring suitable PLD growth methods is particularly important for obtaining AlGaN / GaN-based 35GHz millimeter-wave rectifiers with high heat dissipation capabilities. Summary of the Invention

[0003] To address the shortcomings and deficiencies of existing technologies, the primary objective of this invention is to provide an AlGaN / GaN-based 35GHz millimeter-wave rectifier.

[0004] Another objective of this invention is to provide a method for fabricating an AlGaN / GaN-based 35GHz millimeter-wave rectifier, which has the advantages of high compatibility with existing production methods and ease of implementation.

[0005] Another object of the present invention is to provide an application of the aforementioned AlGaN / GaN-based 35GHz millimeter-wave rectifier.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] An AlGaN / GaN-based 35GHz millimeter-wave rectifier, the structure of which, from bottom to top, consists of an Al substrate and undoped Al... x Ga 1-xThe system includes an N-layer and an undoped GaN layer, and further comprises a mesa isolation groove and a Schottky contact electrode; the bottom of the mesa isolation groove is located at the undoped Al layer. x Ga 1-x The N-layer has one side in contact with the undoped GaN layer and the other side in contact with the Schottky contact electrode. A layer of SiN is deposited on the inner surface of the mesa isolation groove. y Passivation layer; the bottom of the Schottky contact electrode is located on undoped Al. x Ga 1- x Layer N, one side of which contacts the isolation groove on the platform, and the other side is the side of the rectifier, where x = 0.15~0.2 and y = 1.37~1.53.

[0008] Preferably, the undoped Al x Ga 1-x The thickness of the N layer is 300–320 nm, and the thickness of the undoped GaN layer is 20–30 nm.

[0009] Preferably, the depth of the isolation groove on the platform is 245–255 nm; and the thickness of the Schottky contact electrode is 190–200 nm.

[0010] Preferably, the bottom length of the isolation groove on the platform is 95-105 μm and the top length is 145-155 μm; the bottom length of the Schottky contact electrode is 155-165 μm and the top length is 115-125 μm; and the length of the AlGaN / GaN-based 35GHz millimeter-wave rectifier is 800 μm.

[0011] Preferably, the SiN on the inner surface of the platform isolation groove is... y The thickness of the passivation layer is 8–12 nm.

[0012] Preferably, the AlGaN / GaN-based 35GHz millimeter-wave rectifier epitaxial wafer is fabricated using Al and Ga targets as raw materials and pulsed laser technology.

[0013] More preferably, the AlGaN / GaN-based 35GHz millimeter-wave rectifier epitaxial wafer is fabricated by the following method: at room temperature, using Al and Ga targets as raw materials, undoped Al is grown on an Al substrate using pulsed laser technology (PLD). x Ga 1-x N layers, then using Ga target material as raw material, and utilizing PLD on undoped Al x Ga 1-x An undoped GaN layer is grown on the N-layer to obtain a rectifier epitaxial wafer.

[0014] The above-mentioned method for fabricating an AlGaN / GaN-based 35GHz millimeter-wave rectifier includes the following steps:

[0015] (1) At room temperature, using Al and Ga targets as raw materials, undoped Al is grown on an Al substrate using pulsed laser technology (PLD). x Ga 1-x N layers, then using Ga target material as raw material, and utilizing PLD on undoped Al x Ga 1-x An undoped GaN layer is grown on the N layer to obtain a rectifier epitaxial wafer, x = 0.15~0.2;

[0016] (2) The rectifier epitaxial wafer obtained in step (1) is placed in acetone and anhydrous ethanol for ultrasonic treatment in sequence. After being taken out, it is cleaned with deionized water and then dried with nitrogen.

[0017] (3) Transfer the Schottky contact pattern to the rectifier epitaxial wafer obtained in step (2): uniformly spin-coat photoresist on the rectifier epitaxial wafer obtained in step (2), expose it, and clean it with developer to make the pattern appear.

[0018] (4) Using reactive ion etching, grooves are etched along the Schottky contact electrode pattern in the rectifier epitaxial wafer obtained in step (3) to obtain the Schottky contact electrode pattern groove.

[0019] (5) The metal is deposited into the Schottky contact electrode pattern groove of the rectifier epitaxial wafer obtained in step (4) by vapor deposition, and then annealed to obtain the Schottky contact electrode.

[0020] (6) Immerse the rectifier epitaxial wafer obtained in step (5) in the desizing solution, rinse with deionized water, then place it in acetone for ultrasonic treatment, and dry it with nitrogen gas.

[0021] (7) Spin-coat photoresist uniformly onto the rectifier epitaxial wafer obtained in step (6), expose it, clean it with developer, prepare a mesa isolation pattern on the surface of the rectifier epitaxial wafer, and then use reactive ion etching to etch grooves along the mesa isolation pattern.

[0022] (8) Place the rectifier epitaxial wafer with the etched grooves of the mesa isolation pattern obtained in step (7) into a plasma-enhanced chemical vapor deposition (PECVD) apparatus, heat it up, and after evacuation, introduce carrier gas and reactive gas to deposit SiN on the surface of the rectifier epitaxial wafer. y Passivation layer, where y = 1.37–1.53;

[0023] (9) The residual photoresist and SiN on the surface of the rectifier epitaxial wafer obtained in step (8) are removed by soaking in a resist remover solution and ultrasonic cleaning. y Remove, leaving only the SiN within the etched grooves of the isolating pattern on the mesa. y An AlGaN / GaN-based 35GHz millimeter-wave rectifier was obtained.

[0024] Preferably, the laser energy of the pulsed laser technology in step (1) is 600mJ.

[0025] Preferably, the environment for metal deposition in step (5) is a vacuum, with a vacuum degree of 5 × 10⁻⁶. -5 Pa; the metals are Ni and Au; the annealing temperature is 400℃ and the time is 600min.

[0026] Preferably, the rectifier epitaxial wafer in step (6) is immersed in the adhesive stripping solution for 63 to 67 minutes.

[0027] The above describes the application of an AlGaN / GaN-based 35GHz millimeter-wave rectifier.

[0028] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0029] (1) The Al substrate described in this invention is a high thermal conductivity substrate, and the AlGaN layer is in direct contact with the Al substrate; therefore, when applied to high frequency, the large amount of heat generated can be dissipated quickly, which is suitable for high frequency applications and helps to extend the service life of the rectifier.

[0030] (2) When growing undoped AlGaN layers using the PLD method described in this invention, two pulsed lasers are used to ablate Al and Ga targets respectively to generate Al plasma and Ga plasma, which combine with N plasma to generate AlGaN. This method can grow at room temperature, reduce energy consumption, reduce target cost, and enable large-scale production. Attached Figure Description

[0031] Figure 1 This is a cross-sectional schematic diagram of the rectifier chip obtained in Embodiment 1 of the present invention; wherein 1-Al substrate, 2-undoped Al x Ga 1-x N-layer, 3-undoped GaN layer, 4-SiN y Passivation layer, 5-mesa isolation groove, 6-Schottky contact electrode.

[0032] Figure 2 The positive JV curve of the rectifier obtained in Embodiment 1 of the present invention is shown.

[0033] Figure 3 This is the reverse IV curve of the rectifier obtained in Embodiment 1 of the present invention. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0035] Unless otherwise specified in the embodiments of this invention, the conditions shall be performed according to conventional conditions or conditions recommended by the manufacturer. All raw materials and reagents used, unless otherwise specified, are commercially available conventional products.

[0036] Example 1

[0037] The structure of the AlGaN / GaN-based 35GHz millimeter-wave rectifier described in this embodiment is as follows: Figure 1 As shown, its structure from bottom to top consists of an Al substrate (1), an undoped Al substrate (2), and an undoped Al substrate (3). x Ga 1-x The N-layer (2) and the undoped GaN layer (3) further include a mesa isolation groove (5) and a Schottky contact electrode (6); the bottom of the mesa isolation groove (5) is located at the undoped Al x Ga 1-x The N-layer (2) is in contact with the undoped GaN layer (3) on one side and with the Schottky contact electrode (6) on the other side. A layer of SiN is deposited on the inner surface of the mesa isolation groove (5). y Passivation layer (4); the bottom of the Schottky contact electrode (6) is located on undoped Al x Ga 1-x The N layer (2) is in contact with the tabletop isolation groove (5) on one side and the side of the rectifier on the other side.

[0038] The undoped Al x Ga 1-x The N-layer (2) has a thickness of 300 nm; the undoped GaN layer (3) has a thickness of 20 nm; the Schottky contact electrode (6) has a thickness of 200 nm; the mesa isolation groove (5) has a depth of 250 nm; and SiN is deposited in the mesa isolation groove. y The passivation layer (4) has a thickness of 10 nm; the bottom length of the mesa isolation groove is 100 μm and the top length is 150 μm; the bottom length of the Schottky contact electrode is 160 μm and the top length is 120 μm; the length of the AlGaN / GaN-based 35 GHz millimeter-wave rectifier is 800 μm.

[0039] This embodiment describes a method for fabricating an AlGaN / GaN-based 35GHz millimeter-wave rectifier:

[0040] (1) As Figure 1 As shown, at room temperature, using Al and Ga targets as raw materials, a rectifier epitaxial wafer is grown on a silicon substrate using a PLD, including undoped Al grown on an Al substrate (1) using a PLD. x Ga 1-x N (x is 0.18) layer (2), and then using Ga target as raw material, PLD is used to build undoped Al x Ga 1-xAn undoped GaN layer (3) is grown on the N layer (2); the undoped Al x Ga 1-x The thickness of the N layer (2) is 300 nm; the thickness of the undoped GaN layer (3) is 20 nm, and the laser energy is 600 mJ;

[0041] (2) Place the rectifier epitaxial wafer in acetone and anhydrous ethanol in sequence for ultrasonic treatment for 5 minutes, then take it out, clean it with deionized water, and then dry it with nitrogen.

[0042] (3) A positive photoresist, model AZ5214, with a thickness of 0.3 μm, is spin-coated onto the cleaned rectifier epitaxial wafer. The epitaxial wafer coated with photoresist is placed on a hot stage for pre-baking for 45 s, and then placed in a lithography machine for exposure for 5 s. The exposed epitaxial wafer is then immersed in a developer, model RZX3038, for 60 s to reveal the pattern on the epitaxial wafer. The epitaxial wafer is then rinsed with deionized water and dried with nitrogen. Finally, the epitaxial wafer is placed on a hot stage for baking and hardening for 45 s.

[0043] (4) Using reactive ion etching, grooves are etched along the Schottky contact electrode pattern in the epitaxial wafer of the rectifier, with a groove depth of 200 nm.

[0044] (5) Place the rectifier epitaxial wafer with the Schottky contact electrode pattern groove obtained in step (4) into the electron beam evaporation equipment and evacuate the cavity to a vacuum level of 5×10⁻⁶. -5 Pa, then the electrode metal Ni / Au was deposited sequentially; after the deposition was completed, the rectifier epitaxial wafer was annealed at a temperature of 400℃ for 60 min to obtain the Schottky contact electrode (6).

[0045] (6) Immerse the prepared Schottky contact electrode of the rectifier epitaxial wafer in the desizing solution for 65 minutes, take it out, rinse it with deionized water and place it in acetone for 5 minutes, take it out, rinse it with deionized water and blow it dry with nitrogen.

[0046] (7) Repeat steps (3) and (4) to prepare a mesa isolation pattern on the surface of the epitaxial wafer by photolithography and development. Then, use a reactive ion etching device to etch grooves on the mesa isolation pattern with an etching depth of 250 nm. Finally, clean the surface of the epitaxial wafer with deionized water and blow it dry with nitrogen to obtain mesa isolation grooves (5).

[0047] (8) Fabrication of the mezzanine isolation passivation layer: The rectifier epitaxial wafer is placed in a plasma-enhanced chemical vapor deposition (PECVD) apparatus. The instrument is heated to 400°C, and the cavity vacuum is evacuated to 5×10⁻⁶. -5 Pa, depositing SiN in the etched grooves of the rectifier epitaxial wafer. yPassivation layer (y = 1.37–1.53), deposition time 75 min;

[0048] (9) Immerse the prepared rectifier epitaxial wafer in the desizing solution for 65 min, remove it, rinse with deionized water, and sonicate in acetone for 5 min. After removing it, rinse with deionized water and dry with nitrogen to remove residual SiN from the surface of the rectifier epitaxial wafer. y With photoresist, only the SiN within the etched grooves of the isolating pattern on the mesa is preserved. y (4) Complete the fabrication of AlGaN / GaN-based 35GHz millimeter-wave rectifier.

[0049] The rectifier structure obtained in this embodiment is as follows: Figure 1 As shown. The forward JV curve of the epitaxial wafer is as follows. Figure 2 As shown, the turn-on voltage is 0.81V, and the calculated specific on-resistance RON is 9.2mΩ / sq. Therefore, the device exhibits excellent stability and reliability under high-power operation. The reverse IV curve of the epitaxial wafer is shown below. Figure 3 As shown, under a reverse bias of -20V, the device leakage current is -0.0004A, exhibiting excellent reverse leakage performance. Simultaneously, the defect density of this embodiment was measured to be approximately 2 × 10⁻⁶. 8 cm -2 .

[0050] Example 2

[0051] The structure of the AlGaN / GaN-based 35GHz millimeter-wave rectifier described in this embodiment is as follows: Figure 1 As shown, its structure from bottom to top consists of an Al substrate (1), an undoped Al substrate (2), and an undoped Al substrate (3). x Ga 1-x The N-layer (2) and the undoped GaN layer (3) further include a mesa isolation groove (5) and a Schottky contact electrode (6); the bottom of the mesa isolation groove (5) is located at the undoped Al x Ga 1-x The N-layer (2) is in contact with the undoped GaN layer (3) on one side and with the Schottky contact electrode (6) on the other side. A layer of SiN is deposited on the inner surface of the mesa isolation groove (5). y Passivation layer (4); the bottom of the Schottky contact electrode (6) is located on undoped Al x Ga 1-x The N layer (2) is in contact with the tabletop isolation groove (5) on one side and the side of the rectifier on the other side.

[0052] The undoped Al x Ga 1-xThe N-layer (2) has a thickness of 320 nm; the undoped GaN layer (3) has a thickness of 30 nm; the Schottky contact electrode (6) has a thickness of 200 nm; the mesa isolation groove (5) has a depth of 250 nm; and SiN is deposited in the mesa isolation groove. y The passivation layer (4) has a thickness of 10 nm; the bottom length of the mesa isolation groove is 100 μm and the top length is 150 μm; the bottom length of the Schottky contact electrode is 160 μm and the top length is 120 μm; the length of the AlGaN / GaN-based 35 GHz millimeter-wave rectifier is 800 μm.

[0053] The fabrication method of the AlGaN / GaN-based 35GHz millimeter-wave rectifier in this embodiment:

[0054] (1) As Figure 1 As shown, at room temperature, using Al and Ga targets as raw materials, a rectifier epitaxial wafer is grown on a silicon substrate using a PLD, including undoped Al grown on an Al substrate (1) using a PLD. x Ga 1-x N layers (x is 0.20) (2), and then using Ga target material as raw material, PLD is used to process undoped Al. x Ga 1-x An undoped GaN layer (3) is grown on the N layer (2); the undoped Al x Ga 1-x The thickness of the N layer (2) is 320 nm; the thickness of the undoped GaN layer (3) is 30 nm, and the laser energy is 600 mJ;

[0055] (2) Place the rectifier epitaxial wafer in acetone and anhydrous ethanol in sequence for ultrasonic treatment for 5 minutes, then take it out, clean it with deionized water, and then dry it with nitrogen.

[0056] (3) Spin-coat the cleaned rectifier epitaxial wafer with positive photoresist, model AZ5214, with a photoresist thickness of 0.3μm. Place the photoresist-coated epitaxial wafer on a hot plate for pre-baking for 45s, then place it in a lithography machine for exposure for 5s. After exposure, immerse the epitaxial wafer in a developer solution, model RZX3038, for 60s to make the pattern on the epitaxial wafer visible. Rinse the epitaxial wafer with deionized water and dry it with nitrogen. Finally, place the epitaxial wafer on a hot plate for baking and hardening for 45s.

[0057] (4) Using reactive ion etching, grooves are etched along the Schottky contact electrode pattern in the epitaxial wafer of the rectifier, with a groove depth of 200 nm.

[0058] (5) Place the rectifier epitaxial wafer with the Schottky contact electrode pattern groove obtained in step (4) into the electron beam evaporation equipment and evacuate the cavity to a vacuum level of 5×10⁻⁶. -5Pa, then the electrode metal Ni / Au was deposited sequentially; after the deposition was completed, the rectifier epitaxial wafer was annealed at a temperature of 400℃ for 60 min to obtain the Schottky contact electrode (6).

[0059] (6) Immerse the prepared Schottky contact electrode of the rectifier epitaxial wafer in the desizing solution for 65 minutes, take it out, rinse it with deionized water and place it in acetone for 5 minutes, take it out, rinse it with deionized water and blow it dry with nitrogen.

[0060] (7) Repeat steps (3) and (4) to prepare a mesa isolation pattern on the surface of the epitaxial wafer by photolithography and development. Then, use a reactive ion etching device to etch grooves on the mesa isolation pattern with an etching depth of 250 nm. Finally, clean the surface of the epitaxial wafer with deionized water and blow it dry with nitrogen to obtain mesa isolation grooves (5).

[0061] (8) Fabrication of the mezzanine isolation passivation layer: The rectifier epitaxial wafer is placed in a plasma-enhanced chemical vapor deposition (PECVD) apparatus. The instrument is heated to 400°C, and the cavity vacuum is evacuated to 5×10⁻⁶. -5 Pa, depositing SiN in the etched grooves of the rectifier epitaxial wafer. y Passivation layer (y = 1.37–1.53), deposition time 75 min;

[0062] (9) Immerse the prepared rectifier epitaxial wafer in the desizing solution for 63 min, remove it, rinse with deionized water, and sonicate in acetone for 5 min. After removing it, rinse with deionized water and dry with nitrogen to remove residual SiN from the surface of the rectifier epitaxial wafer. y With photoresist, only the SiN within the etched grooves of the isolating pattern on the mesa is preserved. y (4) Complete the fabrication of AlGaN / GaN-based 35GHz millimeter-wave rectifier.

[0063] The forward JV curve of the rectifier epitaxial wafer obtained in this embodiment shows a turn-on voltage of 0.83V and a calculated specific on-resistance RON of 9.4mΩ / sq. Therefore, the device exhibits excellent stability and reliability under high-power operation. The reverse IV curve of the epitaxial wafer is shown below. Figure 3 As shown, under a reverse bias of -20V, the device leakage current is -0.0005A, exhibiting excellent reverse leakage performance. Simultaneously, the defect density of this embodiment was measured to be approximately 3.5 × 10⁻⁶. 8 cm -2 .

[0064] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. An AlGaN / GaN-based 35 GHz millimeter wave rectifier, characterized by, The structure is Al substrate, undoped Al x Ga 1-x N layer and undoped GaN layer from bottom to top, further comprising mesa isolation groove and Schottky contact electrode; the bottom of the mesa isolation groove is located in the undoped Al x Ga 1-x N layer, one side of which is in contact with the undoped GaN layer and the other side is in contact with the Schottky contact electrode, and a layer of SiN is deposited on the inner surface of the mesa isolation groove y passivation layer; the bottom of the Schottky contact electrode is located in the undoped Al x Ga 1-x N layer, one side of which is in contact with the mesa isolation groove and the other side is the side of the rectifier, wherein x = 0.15-0.2 and y = 1.37-1.

53. The non-doped Al x Ga 1-x The thickness of the GaN layer is 300-320 nm, and the thickness of the non-doped GaN layer is 20-30 nm. The mesa isolation groove depth is 245-255 nm; the thickness of the Schottky contact electrode is 190-200 nm; SiN of the inner surface of the mesa isolation groove y The thickness of the passivation layer is 8-12 nm.

2. The AlGaN / GaN-based 35 GHz millimeter wave rectifier of claim 1, wherein, The bottom length of the mesa isolation groove is 95-105 μm, and the upper length is 145-155 μm; the bottom length of the Schottky contact electrode is 155-165 μm, and the upper length is 115-125 μm; the length of the AlGaN / GaN-based 35 GHz millimeter wave rectifier is 800 μm.

3. The AlGaN / GaN-based 35 GHz millimeter wave rectifier of claim 1, wherein, The non-doped Al of the AlGaN / GaN-based 35GHz millimeter wave rectifier x Ga 1-x N layer and the non-doped GaN layer are prepared by the following method: at room temperature, taking an Al target and a Ga target as raw materials, growing a non-doped Al x Ga 1-x N layer on an Al substrate by using a pulse laser technology, then taking the Ga target as raw material, growing a non-doped GaN layer on the non-doped Al x Ga 1-x Ga layer, thereby obtaining a rectifier epitaxial wafer.

4. The method for preparing an AlGaN / GaN-based 35 GHz millimeter wave rectifier according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: (1) At room temperature, using Al target and Ga target as raw materials, a non-doped Al x Ga 1-x N layer is grown on an Al substrate by pulse laser technology, then using Ga target as raw material, a non-doped GaN layer is grown on the non-doped Al x Ga 1-x N layer by pulse laser technology, obtaining a rectifier epitaxial wafer, x=0.15-0.2; (2) The rectifier epitaxial wafer obtained in step (1) is sequentially subjected to ultrasonic treatment in acetone and anhydrous ethanol, and after being taken out, it is cleaned with deionized water and then dried with nitrogen; (3) The Schottky contact pattern is transferred to the rectifier epitaxial wafer obtained in step (2): the rectifier epitaxial wafer obtained in step (2) is uniformly spin-coated with photoresist, exposed, and cleaned with a developing solution to make the pattern appear; (4) A groove is etched along the Schottky contact electrode pattern of the rectifier epitaxial wafer obtained in step (3) by using a reactive ion etching method, to obtain a Schottky contact electrode pattern groove; (5) Metal is deposited into the Schottky contact electrode pattern groove of the rectifier epitaxial wafer obtained in step (4) by using an evaporation method, and annealing is performed to obtain a Schottky contact electrode; (6) The rectifier epitaxial wafer obtained in step (5) is immersed in a degreasing solution, then washed with deionized water, and then subjected to ultrasonic treatment in acetone and dried with nitrogen; (7) The rectifier epitaxial wafer obtained in step (6) is uniformly spin-coated with photoresist, exposed, and cleaned with a developing solution to prepare a mesa isolation pattern on the surface of the rectifier epitaxial wafer, and then a groove is etched along the mesa isolation pattern by using a reactive ion etching method; (8) Put the rectifier epitaxial wafer with mesa isolation pattern etching groove obtained in step (7) into a plasma enhanced chemical vapor deposition device, heat and after vacuum pumping, introduce carrier gas and reaction gas, deposit SiN on the surface of the rectifier epitaxial wafer y passivation layer, wherein y = 1.37-1.53; (9) The surface residual photoresist and SiN y are removed by soaking in a stripping solution and ultrasonic cleaning, only leaving SiN y in the mesa isolation pattern etching groove, to obtain an AlGaN / GaN-based 35 GHz millimeter wave rectifier.

5. The method for fabricating an AlGaN / GaN-based 35GHz millimeter-wave rectifier according to claim 4, characterized in that, The laser energy of the pulse laser technology in step (1) is 600 mJ; the environment of the metal deposition in step (5) is vacuum, and the vacuum degree is 5x10 -5 Pa; the metal is Ni and Au; and the annealing temperature is 400 ℃, and the time is 600 min.

6. The application of the AlGaN / GaN-based 35 GHz millimeter wave rectifier according to any one of claims 1-3 in a satellite system, an aerospace vehicle, or a household appliance.

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