CN116581143A - Enhanced HEMT device and preparation method and application thereof - Google Patents

Enhanced HEMT device and preparation method and application thereof Download PDF

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CN116581143A
CN116581143A CN202310352671.3A CN202310352671A CN116581143A CN 116581143 A CN116581143 A CN 116581143A CN 202310352671 A CN202310352671 A CN 202310352671A CN 116581143 A CN116581143 A CN 116581143A
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metal electrode
layer
barrier layer
gan
hemt device
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姚若河
张聪
耿魁伟
刘玉荣
朱映彬
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South China University of Technology SCUT
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South China University of Technology SCUT
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Abstract

The invention discloses an enhanced HEMT device, a preparation method and application thereof, wherein the enhanced HEMT device utilizes a polarization effect general formula of an intrinsic grid GaN cap layer and an AlGaN back barrier layer to modulate 2DEG in a channel below a gate metal electrode, and negative net polarization charges are generated at an interface of the intrinsic grid GaN cap layer and the AlInN barrier layer and an interface of a GaN channel layer and the AlGaN back barrier layer due to poor polarization effect of a GaN material and an AlInN material and an AlGaN material, so that energy bands of the AlInN barrier layer and the GaN channel layer are raised, the distance between a conduction band bottom and a Fermi energy level is raised, and then the 2DEG in a channel is exhausted, so that the enhanced HEMT device is realized.

Description

Enhanced HEMT device and preparation method and application thereof
Technical Field
The invention relates to the technical field of microelectronics, in particular to an enhanced HEMT device and a preparation method and application thereof.
Background
GaN is used as a third-generation semiconductor material, and is a popular research direction in the fields of high-temperature, high-power and high-frequency devices because of the advantages of large forbidden bandwidth, high thermal conductivity, high breakdown electric field and the like. HEMT devices formed based on AlGaN/GaN or AlInN/GaN heterojunction have been greatly developed in the high-frequency high-power field. Because the 2DEG is formed based on a heterostructure, the conventional GaN-based HEMT device is a normally-on device, i.e., operating in a depletion mode, requiring a negative voltage source to turn off the device in application, designing additional control circuitry. In view of design of a control circuit, circuit power consumption and safety, an enhanced HEMT device is generally required in the application of the high-power field, and the current mode for realizing the enhanced device comprises a groove grid type, an F ion implantation type and a p-GaN cap layer type. The p-GaN gate cap type is the only device structure currently commercially available in the structure to realize the enhancement device. However, since the ionization energy of the P-type impurity Mg doped with GaN is large, it is difficult to realize high-concentration doping, the threshold voltage is limited by the GaN forbidden band width, and at the same time, the carrier mobility in the channel is reduced due to the outdiffusion of the impurity. In addition, since the schottky diode with its gate metal to p-GaN and the pin diode of p-GaN/AlGaN/GaN form two back-to-back diode gate structures, the injection and emission of charge affects the potential of the p-GaN layer, causing instability of the device threshold voltage and large gate leakage current. While the schottky barrier capacitance changes when different gate voltages are operated, which can cause the device frequency response to change. Accordingly, there is a need for an improved enhancement mode HEMT device structure that addresses the problems with p-GaN cap enhancement mode devices.
Disclosure of Invention
The present invention aims to solve at least one of the above technical problems in the prior art. Therefore, the invention aims to provide an enhanced HEMT device, a preparation method and application thereof, and the device structure can obtain high threshold voltage by adjusting the structural parameters of an intrinsic grid GaN cap layer and an AlGaN back barrier layer, so that the threshold voltage of the device can be controlled more accurately.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the first aspect of the invention provides an enhanced HEMT device, which comprises a substrate layer, an AlGaN back barrier layer and a GaN channel layer which are sequentially stacked; the source metal electrode and the drain metal electrode are arranged at two ends of the GaN channel layer, the AlInN barrier layer is arranged in the middle of the GaN channel layer, and the AlInN barrier layer is respectively contacted with the source metal electrode and the drain metal electrode; a GaN cap layer is arranged at the gate metal electrode on the AlInN barrier layer; a grid metal electrode is arranged on the GaN cap layer; passivation layers are respectively arranged on the AlInN barrier layers between the source metal electrode, the drain metal electrode, the GaN cap layer and the gate metal electrode; the source metal electrode and the drain metal electrode respectively form ohmic contact with the GaN channel layer; the gate metal electrode forms a schottky contact with the GaN cap layer.
According to the invention, the polarization effect general formula of the intrinsic grid GaN cap layer and the AlGaN back barrier layer is utilized to modulate the 2DEG in the channel below the gate metal electrode, and negative net polarization charges are generated at the interface of the intrinsic grid GaN cap layer and the AlInN barrier layer and the interface of the GaN channel layer and the AlGaN back barrier layer due to the poor polarization effect of the GaN material, so that the energy band of the AlInN barrier layer and the GaN channel layer is raised, the distance between the bottom of a conduction band and the Fermi level is raised, and the 2DEG in the channel is exhausted, thereby realizing the enhancement device.
In some embodiments of the invention, the composition of the substrate layer comprises Si, siC, al 2 O 3 At least one of (2); preferably a SiC substrate layer; wherein the Si substrate layer has low cost but poor performance, the SiC substrate layer has good performance but high cost, al 2 O 3 The cost and performance of the substrate layer is intermediate between Si and SiC materials.
In some embodiments of the present invention, the AlGaN back barrier layer comprises 5% to 25% by mass of Al; preferably 8 to 20%.
In some embodiments of the invention, the AlGaN back barrier layer has a thickness of 0.1 μm to 3 μm; preferably 0.5 μm to 3 μm; more preferably 0.8 μm to 3. Mu.m. The thickness of the AlGaN back barrier layer modulates the 2DEG in the channel.
In some embodiments of the present invention, the enhanced HEMT device further comprises a nucleation layer disposed between the substrate and the AlGaN back barrier layer, the nucleation layer improving lattice quality.
In some embodiments of the invention, the nucleation layer has a thickness of 0.1 μm to 1 μm.
In some embodiments of the invention, the nucleation layer comprises at least one of an AlN nucleation layer, an AlGaN nucleation layer, which is integral with the AlGaN back barrier layer when an AlGaN nucleation layer is employed.
In some embodiments of the invention, the AlInN barrier layer has a thickness of 5nm to 100nm; preferably 15nm to 20nm; still more preferably 15nm. The AlInN barrier layer with the thickness can generate high-concentration 2DEG in the channel outside the gate metal electrode, so that parasitic resistance in the source and drain channels outside the gate metal electrode of the device is reduced, and the output current of the device is improved. Secondly, the thin AlInN barrier layer can increase the control capability of the gate metal electrode of the device, improve the transconductance and reduce the process complexity due to the undoped structure.
In some embodiments of the present invention, the AlInN barrier layer has a mass percentage of Al of 82% to 84%; the AlInN barrier layer with the Al content can be matched with lattice constants of the GaN channel layer and the GaN cap layer on the intrinsic gate, so that lattice stress is reduced; meanwhile, the Al component can also generate higher concentration of 2DEG through spontaneous polarization effect, and the output characteristic of the device can be improved.
In some embodiments of the invention, the GaN channel layer has a thickness of 10nm to 100nm; preferably 20nm to 50nm.
In some embodiments of the invention, the GaN cap layer has a thickness of 10nm to 100nm; preferably 15nm to 60nm.
In some embodiments of the invention, the passivation layer comprises SiN, siO 2 、Al 2 O 3 At least one of (a) and (b).
In some embodiments of the invention, the passivation layer has a thickness of 0.1 μm to 5 μm.
In some embodiments of the invention, the source metal electrode comprises a composition of Ti, al, ni, au; the source metal electrode is preferably a Ni/Au two-layer metal electrode.
In some embodiments of the invention, the composition of the drain metal electrode comprises Ti, al, ni, au; the source metal electrode is preferably a Ni/Au two-layer metal electrode.
In some embodiments of the invention, the composition of the gate metal electrode comprises Ti, al, ni, au; the gate metal electrode is preferably a Ti/Al/Ni/Au four-layer metal electrode.
The second aspect of the present invention provides a method for manufacturing the enhanced HEMT device, which includes the following steps:
s1: sequentially epitaxially growing an AlGaN back barrier layer and a GaN channel layer on the substrate layer; after a mask is used in the source metal electrode and drain metal electrode areas, an AlInN barrier layer, a GaN cap layer and a passivation layer are sequentially epitaxially grown;
s2: performing mesa isolation and etching to the AlGaN back barrier layer;
s3: etching to expose the gate metal electrode region;
s4: and depositing a source metal electrode, a drain metal electrode and a gate metal electrode to obtain the enhanced HEMT device.
In some embodiments of the present invention, in S1, an AlGaN back barrier layer, a GaN channel layer, an AlInN barrier layer, and a GaN cap layer are epitaxially grown on a substrate layer in this order using a Metal Organic Chemical Vapor Deposition (MOCVD) at a growth temperature of 850 ℃ to 950 ℃.
In some embodiments of the invention, in S1, a passivation layer is grown using plasma chemical vapor deposition (PECVD) at a temperature of 200 to 300 ℃.
In some embodiments of the invention, in S2, mesa isolation is performed using Reactive Ion Etching (RIE); and chlorine is adopted to etch the AlGaN back barrier layer, so that the conducting channel can be completely isolated.
In some embodiments of the present invention, in S3, a chemical etching process is used to remove the passivation layer in the area under the gate metal electrode; the etching liquid is HF, HN 4 F=1:6 Buffered Oxide Etchant (BOE) solution.
In some embodiments of the present invention, in S4, the source metal electrode, the drain metal electrode, and the gate metal electrode are deposited by electron beam evaporation.
In a third aspect of the present invention, an electronic device is provided, including the enhanced HEMT device.
The beneficial effects of the invention are as follows:
compared with the existing p-GaN gate enhanced HEMT device structure, the device structure has the beneficial effects that: firstly, the problems that the p-type Mg doping is difficult to realize and the mobility is influenced by the fact that Mg impurities are out-diffused into a channel can be avoided; secondly, the grid metal electrode structure of the device has no suspended potential, so that the problem of threshold voltage drift caused by the fact that the p-GaN back-to-back diode is connected with the grid metal electrode structure and the problem of large leakage current of the grid metal electrode are solved; thirdly, the threshold voltage is not limited by the doping concentration of the P-type layer and the forbidden band width of the P-type layer, and the large threshold voltage can be realized through the structural parameter adjustment of the cap layer and the back barrier layer; finally, compared with the p-GaN cap layer which does not need a doping process, compared with impurity activation, the device structure parameters can be accurately determined, so that the threshold voltage of the device can be accurately controlled, the device has good repeatability, and the device structure parameters can be adjusted to realize larger threshold voltage, so that the device is more beneficial to the use of the power device.
Drawings
Fig. 1 is a schematic structural diagram of an enhanced HEMT device according to an embodiment of the present invention.
The attached drawings are used for identifying and describing: 0101. a source metal electrode; 0102. a GaN channel layer; 0103. an AlGaN back barrier layer; 0104. a SiC substrate layer; 0105. an AlInN barrier layer; 0106. a drain metal electrode; 0107. al (Al) 2 O 3 A passivation layer; 0108. a GaN cap layer; 0109. a gate metal electrode.
Fig. 2 is a band diagram under a gate of the enhancement HEMT device according to embodiment 1 of the present invention.
Fig. 3 is a band diagram under a gate of the enhancement HEMT device according to embodiment 2 of the present invention.
Fig. 4 is a band diagram under a gate of an enhanced HEMT device according to embodiment 3 of the present invention.
Fig. 5 is a transfer characteristic diagram of the enhanced HEMT device according to embodiment 1 of the present invention.
Fig. 6 is an output characteristic diagram of the enhanced HEMT device according to embodiment 1 of the present invention.
Detailed Description
The present invention will be described in further detail with reference to specific examples. The starting materials, reagents or apparatus used in the examples and comparative examples were either commercially available from conventional sources or may be obtained by prior art methods unless specifically indicated. Unless otherwise indicated, assays or testing methods are routine in the art.
Example 1
An enhanced HEMT device (structure schematic diagram is shown in fig. 1), which comprises:
the SiC substrate layer 0104, the AlGaN back barrier layer 0103 and the GaN channel layer 0102 are laminated in this order; a source metal electrode 0101 and a drain metal electrode 0106 are arranged at two ends of the GaN channel layer 0102, an AlInN barrier layer 0105 is arranged in the middle of the GaN channel layer 0102, and the AlInN barrier layer 0105 is respectively contacted with the source metal electrode 0101 and the drain metal electrode 0106; a GaN cap layer 0108 is arranged on the AlInN barrier layer 0105 at the gate metal electrode; a gate metal electrode 0109 is arranged on the GaN cap layer 0108; al is arranged on the AlInN barrier layer 0105 between the source metal electrode 0101, the drain metal electrode 0106, the GaN cap layer 0108 and the gate metal electrode 0109 2 O 3 A passivation layer 0107; source metal electrode 0101 and drain metal electrode 0106 form ohmic contact with GaN channel layer 0102, respectively; the gate metal electrode 0109 forms a schottky contact with the GaN cap 0108.
The structural parameters of the enhanced HEMT device are as follows: the Al component of the AlGaN back barrier layer 0103 is 8% by mass and the thickness is 800nm; the thickness of the GaN channel layer 0102 is 20nm; the Al component of the AlInN barrier layer 0105 is 83% by mass and the thickness is 5nm; the thickness of the intrinsic grid GaN cap layer 0108 is 15nm, and the length is 1.5um; the width of the gate metal electrode is 1mm, the source-drain spacing is 7um, the gate-source spacing is 2um, and the gate-drain spacing is 5um; al (Al) 2 O 3 The thickness of the passivation layer 0107 is 500nm; the metal of the source metal electrode 0101 and the drain metal electrode 0106 is Ni/Au to form ohmic contact, and the thickness is thickThe degree is 505nm, the metal of the gate metal electrode 0109 is Ti/Al/Ni/Au to form ohmic contact, and the thickness is 480nm. The 2DEG in the channel below the grid is modulated simultaneously by utilizing the polarization effect of the intrinsic grid GaN cap layer 0108 and the AlGaN back barrier layer 0103, so that an enhanced device is realized, the grid control capability of the device is improved by the thin AlInN barrier layer 0103, the transconductance is improved, and the process complexity is reduced by an undoped structure.
The preparation method of the enhanced HEMT device comprises the following steps:
step 1: alGaN back barrier layer 0103 is epitaxially grown on SiC substrate layer 0104 by Metal Organic Chemical Vapor Deposition (MOCVD), and the organic source gases of group III metal aluminum (Al) and gallium (Ga) are Trimethylaluminum (TMAL) and trimethylgallium (TMGa), respectively, so TMGa needs to be introduced on the basis of the gas of step 1, and the nitrogen (N) source is also high-purity ammonia (NH) 3 ) Hydrogen (H) 2 ) And nitrogen (N) 2 ) The components of Al and Ga in the AlGaN back barrier layer 0103 can be controlled by controlling the flow mole ratio of TMAl and TMGa source gas entering the reaction chamber, and the growth temperature is 900 ℃;
step 2: then growing a GaN channel layer 0102 on the epitaxial wafer obtained in the step 1 by Metal Organic Chemical Vapor Deposition (MOCVD), wherein the gallium (Ga) source is trimethylgallium (TMGa) and high-purity ammonia (NH) as the nitrogen (N) source 3 ) Hydrogen (H) 2 ) And nitrogen (N) 2 ) As carrier gas, so that Al source Trimethylaluminum (TMAL) needs to be removed on the basis of the gas in the step 1, and the growth temperature is 900 ℃;
step 3: next, an AlInN barrier layer 0105 is grown on the epitaxial wafer obtained in step 2 by Metal Organic Chemical Vapor Deposition (MOCVD), because the source metal electrode 0101 and the drain metal electrode 0106 are above the GaN channel layer 0108, a mask is required so that the AlInN barrier layer is not grown at the source metal electrode and the drain metal electrode. The organic source gases of aluminum (Al) and indium (In) are Trimethylaluminum (TMAL) and trimethylindium (TMIn), respectively, so TMGa needs to be removed on the basis of the gases In the step 1, TMAL and TMIn are introduced, and the nitrogen (N) source is high-purity ammonia (NH) 3 ) Hydrogen (H) 2 ) And nitrogen (N) 2 ) Is used as the mixed gas of (1)As carrier gas, the components of Al and In the AlInN barrier layer can be controlled by controlling the flow mole ratio of TMAl and TMGa source gas entering the reaction chamber, and the growth temperature is 900 ℃;
step 4: then, an intrinsic gate GaN cap 0108 is grown on the epitaxial wafer obtained in step 3 by Metal Organic Chemical Vapor Deposition (MOCVD), because the intrinsic gate metal GaN cap 0108 is grown on the gate metal electrode portion of AlInN barrier 0105, a reticle is required to not grow the GaN cap on the gate outer portion. Gallium (Ga) source is trimethyl gallium (TMGa) and high purity ammonia (NH) as nitrogen (N) source 3 ) Hydrogen (H) 2 ) And nitrogen (N) 2 ) As carrier gas, TMGa needs to be added on the basis of the gas in the step 3, TMAL and TMIn are removed, and the growth temperature is 900 ℃;
step 5: next, al is grown on the epitaxial wafer obtained in step 4 by employing plasma chemical vapor deposition (PECVD) 2 O 3 Passivation layer 0107, using source metal electrode 0101 and drain metal electrode 0106 mask to not grow Al at source metal electrode 0101 and drain metal electrode 0106 2 O 3 And a passivation layer. The oxygen (O) source is formed by oxygen (O) 2 ) The aluminum (Al) source gas was Trimethylaluminum (TMAL) and the growth temperature was 250 ℃.
Step 6: then, the epitaxial wafer obtained in the step 5 is subjected to mesa isolation by using a Reactive Ion Etching (RIE) method, wherein the etching gas used is chlorine (Cl) 2 ) Etching to the AlGaN back barrier layer 0103 ensures that the conducting channel can be completely isolated.
Step 7: then removing Al in the area under the epitaxial wafer gate metal electrode obtained in the step 6 by a chemical etching treatment method 2 O 3 The passivation layer 0107, the etching liquid is HF, HN 4 F=1:6 Buffered Oxide Etchant (BOE) solution soak.
Step 8: and then, carrying out metal deposition on the source metal electrode 0101 and the drain metal electrode 0106 of the epitaxial wafer obtained in the step 7 by an electron beam evaporation mode, and forming ohmic contact by adopting a typical Ti/Al/Ni/Au four-layer alloy structure, wherein the thicknesses of the metals are 22nm, 140nm, 55nm and 45nm in sequence. And adjusting the metal evaporation rate according to the thickness of each layer of metal in the evaporation process, and performing high-temperature annealing in a rapid annealing furnace at the temperature of 830 ℃ after the evaporation is finished so as to form ohmic contact with good performance.
Step 9: and (3) carrying out metal deposition on the gate metal electrode 0109 of the epitaxial wafer obtained in the step (7) by an electron beam evaporation mode, wherein the metal structure of the gate metal electrode is Ni/Au alloy, and the thickness is 45nm and 100nm, so that Schottky contact is formed.
Example 2
The difference between the preparation enhancement type HEMT device and the embodiment 1 is that the thickness of the GaN cap layer is different:
the thicknesses of the GaN cap layers are 5nm, 10nm, 15nm, 20nm and 25nm respectively, and other structures and preparation methods of the device are the same as those of the embodiment 1.
Example 3
The difference between the preparation of the enhanced HEMT device and the preparation of the enhanced HEMT device in embodiment 1 is that the thickness of the AlGaN back barrier layer is 1 μm, and Al components with different mass percentage contents are arranged:
the mass percentage content of Al components in the AlGaN back barrier layer is respectively set to be 4%, 6%, 8%, 10% and 12%, and other structures and preparation methods of the device are the same as those in the embodiment 1.
Test examples
The band diagram under the gate of the enhanced HEMT device of embodiment 1 is shown in FIG. 2, wherein σ is the charge density of the interface, which is the gate metal interface charge σ, respectively s The method comprises the steps of carrying out a first treatment on the surface of the Net polarization charge sigma of intrinsic gate GaN cap layer GaN The method comprises the steps of carrying out a first treatment on the surface of the Net polarization charge sigma of AlInN barrier layer AlInN The method comprises the steps of carrying out a first treatment on the surface of the Net polarization charge sigma of GaN channel layer GaN The method comprises the steps of carrying out a first treatment on the surface of the Net polarization charge sigma of AlGaN back barrier layer AlGaN ；σ b The polarization charge from the AlGaN back barrier layer cooperates with the charge of the substrate layer as a net charge at the bottom interface of the back barrier layer. Because the polarization effect of the GaN material, the AlInN material and the AlGaN material is poor, negative net polarization charges can be generated at the interface of the intrinsic grid GaN cap layer and the AlInN barrier layer and the interface of the GaN channel layer and the AlGaN back barrier layer, thereby raising the energy bands of the AlInN barrier layer and the GaN channel layer and raising the conduction band bottom and the AlInN back barrier layerThe distance between the fermi levels, and thus the 2DEG in the channel, is depleted.
The band diagrams under the gates of the enhancement HEMT devices of embodiment 2 and embodiment 3 are shown in fig. 3 and fig. 4, respectively. It can be seen that as the GaN cap thickness increases, the band rise of the GaN channel layer increases, indicating an enhancement of depletion of the 2DEG in the channel below the gate metal electrode, whereas a 15nm thick GaN cap layer is chosen because the increase in GaN cap thickness reduces the controllability of the gate metal electrode to the channel, thus compromising the GaN cap thickness. While an enhancement mode device with higher threshold voltages can be achieved with an increase in the depletion of the 2DEG in the channel under the gate metal electrode with an increase in the Al composition of the AlGaN back barrier layer, the Al composition is preferably 8% because an increase in the Al composition simultaneously reduces the 2DEG at the channel outside the gate metal electrode.
The transfer characteristic curve and the output characteristic curve of the enhanced HEMT device of example 1 are shown in fig. 5 and 6, respectively, it can be seen that the enhanced device is successfully realized after the intrinsic gate GaN cap layer and the AlGaN back barrier layer are added, the enhanced device is successfully realized under the 15nm thick cap layer and the AlGaN back barrier layer with the thickness of 800nm and the Al composition of 8%, the threshold voltage of the device is 0.8V, the maximum transconductance is 240mS/mm, and the maximum output current is 1.71A/mm when the gate voltage is 10V and the drain electrode voltage is 10V.
The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.

Claims (10)

1. An enhancement mode HEMT device, its characterized in that: comprises a substrate layer, an AlGaN back barrier layer and a GaN channel layer which are sequentially laminated; the source metal electrode and the drain metal electrode are arranged at two ends of the GaN channel layer, the AlInN barrier layer is arranged in the middle of the GaN channel layer, and the AlInN barrier layer is respectively contacted with the source metal electrode and the drain metal electrode; a GaN cap layer is arranged at the gate metal electrode on the AlInN barrier layer; a grid metal electrode is arranged on the GaN cap layer; passivation layers are respectively arranged on the AlInN barrier layers between the source metal electrode, the drain metal electrode, the GaN cap layer and the gate metal electrode; the source metal electrode and the drain metal electrode respectively form ohmic contact with the GaN channel layer; the gate metal electrode forms a schottky contact with the GaN cap layer.
2. The enhancement HEMT device of claim 1, wherein: the mass percentage of Al in the AlGaN back barrier layer is 5% -25%.
3. The enhancement HEMT device of claim 1, wherein: the thickness of the AlGaN back barrier layer is 0.1-3 μm.
4. The enhancement HEMT device of claim 1, wherein: the thickness of the AlInN barrier layer is 5 nm-25 nm.
5. The enhancement HEMT device of claim 1, wherein: the mass percentage of Al in the AlInN barrier layer is 82-84%.
6. The enhancement HEMT device of claim 1, wherein: the thickness of the GaN cap layer is 10 nm-100 nm.
7. The enhancement HEMT device of claim 1, wherein: the thickness of the GaN channel layer is 10 nm-100 nm.
8. The enhancement HEMT device of claim 1, wherein: the enhanced HEMT device further comprises a nucleation layer arranged between the substrate and the AlGaN back barrier layer.
9. A method for manufacturing the enhanced HEMT device according to any one of claims 1-8, wherein: the method comprises the following steps:
s1: sequentially epitaxially growing an AlGaN back barrier layer and a GaN channel layer on the substrate layer; after a mask is used in the source metal electrode and drain metal electrode areas, an AlInN barrier layer, a GaN cap layer and a passivation layer are sequentially epitaxially grown;
s2: performing mesa isolation and etching to the AlGaN back barrier layer;
s3: etching to expose the gate metal electrode region;
s4: and depositing a source metal electrode, a drain metal electrode and a gate metal electrode to obtain the enhanced HEMT device.
10. An electronic device comprising the enhancement HEMT device of any one of claims 1-8.
CN202310352671.3A 2023-04-03 2023-04-03 Enhanced HEMT device and preparation method and application thereof Pending CN116581143A (en)

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