A gallium nitride high electron mobility transistor resistant to single event radiation hardening

Abstract

The application discloses a kind of anti single particle radiation reinforced gallium nitride high electron mobility transistor, comprising: Si substrate, GaN buffer layer, N type AlGaN layer being arranged in the top layer local position of GaN buffer layer, AlGaN barrier layer being arranged on GaN buffer layer and N type AlGaN layer, P type GaN layer being arranged above N type AlGaN layer and inside AlGaN barrier layer, surface SiN passivation layer, and drain electrode, gate electrode, source electrode;The N type AlGaN layer is generated below barrier layer between gate and drain in the application, so that output current is improved;By generating P type GaN layer and N type AlGaN layer between source and drain, the conduction band energy level can be raised, the injection of electrons from source to buffer layer under off state is blocked, the buffer layer leakage current is reduced, the internal electric field of device is weakened, the collision ionization generation of electron-hole pair is reduced, the single particle transient current is reduced, and the device radiation resistance performance is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of semiconductor devices, and particularly relates to a gallium nitride high electron mobility transistor with single-particle radiation hardening. BACKGROUND

[0002] Gallium nitride material is widely used in the fields of automobile electronics, power supply, 5G base station, etc. due to its excellent characteristics such as wide band gap, high temperature and pressure resistance, and high electron saturation velocity. In addition, gallium nitride material has a unique advantage in aerospace and satellite detection fields due to its high switching frequency and power density. Due to long time in space environment, the influence of high-energy particles in space on device reliability cannot be ignored. Research shows that high-energy particles in space will affect the electrical characteristics of the device such as output characteristics, transfer characteristics and transconductance, and some will directly damage the structure of the device. Single-particle effect is an important factor affecting the application of devices in space.

[0003] Single-particle effect is due to the incidence of high-energy particles in space into the device to produce a large number of hole-electron pairs. Under the action of the electric field, these electrons will continue to collide and ionize more hole-electron pairs in the device. These hole-electron pairs are absorbed by the electrode through the ways of recombination, diffusion and drift, which produces a large transient current and makes the device performance degrade. Single-particle effect also changes the characteristics of traps in the device material, introduces leakage current between the drain and the substrate, damages the device characteristics, or causes damage between the drain and the source. When the damage is serious, even gate breakdown may occur. In recent years, domestic and foreign scholars have studied single-particle effect through simulation software and space environment ground simulation devices. It is found that the degradation of the electrical characteristics of the device is related to the type of incident particles and the time of particle incidence.

[0004] Research shows that the transient current can be reduced by introducing an additional electrode to absorb electron-hole pairs in time and by changing the leakage current path through the device structure. At present, there are few studies on the anti-radiation reinforcement structure of gallium nitride devices.

[0005] In the prior art, Zhou T et al. proposed to realize an anti-radiation reinforcement device by adding a grounded Schottky metal. This method adds a grounded Schottky metal between the gate metal and the drain metal by electron beam evaporation. The grounded Schottky metal can extract electrons generated by heavy ion radiation in time, reduce the transient current of the device, and enable the device to resist stronger radiation in the off state. However, the anti-radiation reinforcement structure of the Schottky metal needs an additional ground electrode to discharge electrons in time to reduce the transient current, which will make the device structure complex and increase the difficulty of circuit design. Moreover, the Schottky metal will also increase the on-resistance and seriously degrade the output characteristics of the device.

[0006] Neha et al. proposed to realize the anti-radiation hardened device by double field plate structure. The method adds a long field plate on the right side of the source electrode and a short field plate on the right side of the gate electrode, changes the internal electric field distribution of the device, reduces the internal electric field of the device, reduces the generation of electron-hole pairs, and reduces the transient current generated by single particle injection when the device is in off state. However, the double field plate structure changes the internal electric field distribution of the device at the same time, which increases the area of the metal electrode and generates additional parasitic capacitance, which seriously degrades the high frequency characteristics of the device, reduces the current gain cutoff frequency and the highest oscillation frequency of the device, and affects the performance and stability of the device in the working process.

[0007] Hu X et al. proposed to realize the anti-radiation hardened device by introducing an AlGaN insertion layer. The method inserts an AlGaN insertion layer below the gallium nitride channel layer, which raises the conduction band level and plays the role of back barrier, preventing the injection of electrons from the source electrode to the buffer layer when the device is in off state, thereby reducing the transient current. However, the AlGaN insertion layer only makes it difficult for electrons to inject into the buffer layer by introducing a new quantum well, and does not reduce the peak electric field inside the device, so the degree of transient current reduction is less, and the process requirements are improved, which has low feasibility in actual production and cannot meet the industrialization demand well.

[0008] It can be seen that the existing technology introduces a series of reliability problems by introducing field plates, AlGaN insertion layers, and Schottky metals while hardening gallium nitride devices. For example, the gate field plate generates additional parasitic capacitance, which reduces the cutoff frequency of the device; the hardening effect of the AlGaN insertion layer is not obvious; and the Schottky metal has a great impact on the saturation current.

[0009] As people's exploration of the universe deepens, the damage of high-energy particles in space to devices is a problem that must be faced and solved, so the radiation reliability of devices in space is particularly important. Therefore, the anti-radiation hardening structure of gallium nitride devices still needs to be further studied, and it is necessary to design a new structure device with strong anti-single particle effect under the premise of ensuring good output characteristics of the device. SUMMARY

[0010] In order to solve the above problems existing in the prior art, the present application provides a preparation method of a gallium nitride high electron mobility transistor resistant to single particle radiation hardening. The technical problem to be solved by the present application is solved by the following technical scheme:

[0011] In a first aspect, the embodiments of the present application provide a gallium nitride high electron mobility transistor resistant to single particle radiation hardening, comprising:

[0012] A Si substrate, a GaN buffer layer disposed on the Si substrate, an N-type AlGaN layer disposed at a top layer local position in the GaN buffer layer, an AlGaN barrier layer disposed on the GaN buffer layer and the N-type AlGaN layer, a P-type GaN layer disposed above the N-type AlGaN layer and inside the AlGaN barrier layer, a SiN passivation layer disposed on the AlGaN barrier layer and the P-type GaN layer, and a drain electrode, a gate electrode, and a source electrode;

[0013] The drain electrode is located outside a laminated structure of the AlGaN barrier layer, the P-type GaN layer, and the SiN passivation layer, close to one side of the P-type GaN layer, the source electrode is located on the other side of the laminated structure, the gate electrode is located inside the SiN passivation layer, close to one side of the AlGaN barrier layer above the P-type GaN layer, a lower surface of the P-type GaN layer contacts an upper surface of the N-type AlGaN layer, and a width of the P-type GaN layer is less than a width of the N-type AlGaN layer.

[0014] In an embodiment of the present application, the GaN buffer layer has a thickness of 1.945 μm.

[0015] In an embodiment of the present application, the N-type AlGaN layer has a doping concentration of 1×1018 cm-3 and a thickness of 0.01 μm. 18 cm -3

[0016] In an embodiment of the present application, the AlGaN barrier layer has a thickness of 0.015 μm.

[0017] In an embodiment of the present application, the P-type GaN layer has a doping concentration of 1×1018 cm-3 and a thickness of 0.015 μm. 16 cm -3

[0018] In an embodiment of the present application, a distance between the source electrode and the drain electrode is 1.5 μm.

[0019] In an embodiment of the present application, a distance between the source electrode and the gate electrode is 4 μm.

[0020] In a second aspect, an embodiment of the present application provides a preparation method of a single-event radiation hardening gallium nitride high electron mobility transistor, and the method comprises:

[0021] A GaN buffer layer is epitaxially grown on a Si substrate by a metal organic chemical vapor deposition method;

[0022] ​​A first recess is made at a top layer local position in the grown GaN buffer layer by an etching process, AlGaN is grown in the first recess by a metal organic chemical vapor deposition method, and an N-type AlGaN layer is formed by ion implantation;

[0023] An AlGaN barrier layer is epitaxially grown on the whole surface of the GaN buffer layer by a metal organic chemical vapor deposition method;

[0024] A second recess is made at a position opposite to the N-type AlGaN layer in the grown AlGaN barrier layer by an etching process, wherein a lower surface of the second recess contacts an upper surface of the N-type AlGaN layer, and a width of the second recess is smaller than a width of the first recess;

[0025] After GaN is grown in the second recess by a metal organic chemical vapor deposition method, Mg ion doping is performed by an ion implantation process to form a P-type GaN layer;

[0026] SiN is deposited on the surface where the AlGaN barrier layer and the P-type GaN layer are located by a PECVD process, and a SiN passivation layer is formed by high-temperature annealing;

[0027] Source electrode, drain electrode and gate electrode positions are obtained by removing the SiN passivation layer in the source electrode, drain electrode and gate electrode regions through an etching process after the source electrode, drain electrode and gate electrode regions are defined by a photolithography process;

[0028] The corresponding metals are deposited at the source electrode position, the drain electrode position and the gate electrode position by metal evaporation, and the metals deposited at the source electrode and the drain electrode position form source and drain electrode ohmic contacts after high-temperature annealing, and the metal deposited at the gate electrode position directly forms a Schottky contact.

[0029] In an embodiment of the present application, the source electrode region, the drain electrode region and the gate electrode region defined by the photolithography process are located as follows:

[0030] The drain electrode region is located outside the laminated structure composed of the AlGaN barrier layer, the P-type GaN layer and the SiN passivation layer, and close to one side of the P-type GaN layer;

[0031] The source electrode region is located at the other side of the laminated structure;

[0032] The gate electrode region is located in the SiN passivation layer and close to one side of the source electrode region above the AlGaN barrier layer.

[0033] In an embodiment of the present application, when the N-type AlGaN layer is formed by ion implantation, the doping concentration is 1×1018cm-2. 18 cm-3 ;

[0034] When Mg ion doping is carried out by an ion implantation process to generate a P-type GaN layer, the doping concentration is 1x10 16 cm -3 .

[0035] Compared with the existing anti-radiation reinforced device technology, the application has the following advantages:

[0036] (1) The P-type GaN layer is located at the gate and drain interlayer (i.e. the AlGaN interlayer), which can raise the band of the AlGaN side, i.e. raise the conduction band level of the heterojunction, and has no effect on the high-frequency characteristics of the device, so that the device has high anti-radiation performance without increasing the additional parasitic capacitance of the metal electrode area. The structure can effectively avoid the problems of increased parasitic capacitance and degraded high-frequency characteristics of the double field plate structure device;

[0037] (2) The N-type AlGaN layer is introduced below the P-type GaN layer, which can compensate the two-dimensional electron gas in the channel and improve the output current. The P-type GaN layer and the N-type AlGaN layer work together to weaken the internal electric field of the device and reduce the generation of hole-electron pairs and the single particle transient current;

[0038] (3) The application does not introduce additional electrodes, optimizes the device structure, and makes the circuit design simpler. The device can meet the actual application well while still having high anti-radiation capability. The structure can effectively avoid the problem of introducing an additional ground electrode in the Schottky metal structure, which makes the device structure complex and increases the difficulty of circuit design;

[0039] (4) By changing the position structure parameters and doping concentration of the P-type GaN layer and the N-type AlGaN layer, high anti-radiation performance and output characteristics can be achieved to ensure the radiation reliability of the device and make the application field of the device more extensive. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 A structure schematic diagram of a single particle radiation reinforced gallium nitride high electron mobility transistor provided by the embodiment of the application is shown in the figure;

[0041] Figure 2 A flowchart of a preparation method of a single particle radiation reinforced gallium nitride high electron mobility transistor provided by the embodiment of the application is shown in the figure;

[0042] Figures 3a-3j A process flowchart of a preparation method of a single particle radiation reinforced gallium nitride high electron mobility transistor provided by the embodiment of the application is shown in the figure.

[0043] Reference signs:

[0044] 1, Si substrate; 2, GaN buffer layer; 3, N-type AlGaN layer; 4, AlGaN barrier layer; 5, P-type GaN layer; 6, SiN passivation layer; 7, drain electrode; 8, gate electrode; 9, source electrode. DETAILED DESCRIPTION

[0045] The application will be described in further detail below with reference to specific embodiments, but the embodiments of the application are not limited thereto.

[0046] Gallium nitride devices are widely used in aerospace, space exploration and satellite communication due to their high switching frequency, high temperature resistance, high electron saturation velocity and high critical breakdown field strength. In space radiation environment, high-energy particles and cosmic rays have a great impact on the electrical parameters of electronic devices, and may even directly cause permanent failure of the devices. For high-voltage devices, single particle effect is a key factor affecting their space application. At present, radiation hardening of gallium nitride devices is usually achieved by introducing Schottky metal, field plate and AlGaN insertion layer, which brings new reliability problems and does not take into account the changes of the band structure of the device and the internal electric field distribution.

[0047] In view of the above-mentioned deficiencies in process and structure of the anti-radiation hardened device, based on the current technical level and process development, the embodiments of the present application provide a single particle radiation hardened gallium nitride high electron mobility transistor and a preparation method thereof.

[0048] In a first aspect, the embodiments of the present application provide a single particle radiation hardened gallium nitride high electron mobility transistor, as shown in Figure 1 , comprising:

[0049] Si substrate 1, GaN buffer layer 2 arranged on the Si substrate 1, N-type AlGaN layer 3 arranged at a local position of the top layer in the GaN buffer layer 2, AlGaN barrier layer 4 arranged above the GaN buffer layer 2 and the N-type AlGaN layer 3, P-type GaN layer 5 arranged above the N-type AlGaN layer 3 and inside the AlGaN barrier layer 4, SiN passivation layer 6 arranged above the AlGaN barrier layer 4 and the P-type GaN layer 5, and drain electrode 7, gate electrode 8 and source electrode 9;

[0050] The drain electrode 7 is located outside the laminated structure of the AlGaN barrier layer 4, the P-type GaN layer 5 and the SiN passivation layer 6, close to one side of the P-type GaN layer 5, and the source electrode 9 is located outside the other side of the laminated structure; the gate electrode 8 is located inside the SiN passivation layer 6, above the AlGaN barrier layer 4 and close to one side of the source electrode 9; the lower surface of the P-type GaN layer 5 contacts the upper surface of the N-type AlGaN layer 3, and the width of the P-type GaN layer 5 is smaller than the width of the N-type AlGaN layer 3.

[0051] Specifically, the thickness of the Si substrate 1 can be selected as needed.

[0052] The GaN buffer layer 2 is arranged on the upper surface of the Si substrate 1, and the thickness thereof can also be selected as needed. In a preferred embodiment, the thickness of the GaN buffer layer 2 can be 1.945 μm after the device parameters are adjusted by using SILVACO TCAD simulation software, so as to achieve the optimal device performance.

[0053] The N-type AlGaN layer 3 is arranged at a local position of the top layer of the GaN buffer layer 2, and is formed by etching a groove in the GaN buffer layer 2, depositing AlGaN by using metal organic chemical vapor deposition and performing ion implantation of a certain concentration. As shown in Figure 1 The upper surface of the N-type AlGaN layer 3 is flush with the upper surface of the surrounding GaN buffer layer 2, and the N-type AlGaN layer 3 is located close to one side edge of the GaN buffer layer 2 and is not located at the center position.

[0054] The thickness and doping concentration of the N-type AlGaN layer 3 can be selected as needed. In the embodiment, Si ions are used for doping, and in a preferred embodiment, the doping concentration of the N-type AlGaN layer 3 can be 1×1018cm-3, and the thickness thereof can be 0.01 μm, so as to achieve the optimal anti-radiation effect. 18 cm -3

[0055] As shown in Figure 1 ​As shown, the AlGaN barrier layer 4 is located on the upper surface of the GaN buffer layer 2 and the N-type AlGaN layer 3, and the AlGaN barrier layer 4 is divided into two parts. Between the two parts of the AlGaN barrier layer 4 is a P-type GaN layer 5, and the P-type GaN layer 5 is formed by groove etching the original complete AlGaN barrier layer 4, depositing GaN by metal organic chemical vapor deposition, and then ion doping, wherein the doped ions are Mg ions; in the embodiment of the present invention, the AlGaN barrier layer 4 and the P-type GaN layer 5 have the same thickness, but it should be noted that the P-type GaN layer 5 is located directly above the N-type AlGaN layer 3, the two surfaces are in contact, and the width of the P-type GaN layer 5 is smaller than the width of the N-type AlGaN layer 3. This is because P-type gallium nitride can raise the conduction band barrier, hindering electron movement and reducing the single-particle transient current. At the same time, the N-type aluminum gallium nitride below can improve the problem of output characteristics degradation caused by P-type doping, thereby improving the output characteristics of the device, thereby reducing the single-particle transient current of the device, enhancing radiation resistance, and maintaining good output characteristics. In a preferred embodiment, the thickness of the AlGaN barrier layer 4 and the P-type GaN layer 5 can be 0.015μm; the doping concentration of the P-type GaN layer 5 can be 1×10 16 cm -3 , in order to achieve the best anti-radiation effect.

[0056] The SiN passivation layer 6 is located on the upper surfaces of the AlGaN barrier layer 4 and the P-type GaN layer 5 , and the thickness can be selected as needed.

[0057] like Figure 1 As shown, for the stacked structure consisting of the AlGaN barrier layer 4, the P-type GaN layer 5, and the SiN passivation layer 6, the drain electrode 7 is located outside the stacked structure, close to the P-type GaN layer 5, and its lower surface is in contact with the upper surface of the GaN buffer layer 2; the source electrode 9 is located outside the stacked structure, away from the P-type GaN layer 5, and its lower surface is in contact with the upper surface of the GaN buffer layer 2; the gate electrode 8 is located in the SiN passivation layer 6, and its lower surface is in contact with the AlGaN barrier layer 4, and the gate electrode 8 is located on the side close to the source electrode 9; that is, from a spatial position point of view, the region where the P-type GaN layer 5 and the N-type AlGaN layer 3 are located is between the gate electrode 8 and the drain electrode 7.

[0058] The spacing between the electrodes can be selected as needed. In a preferred embodiment, the spacing between the source electrode 9 and the drain electrode 7 can be 1.5 μm. The spacing between the source electrode 9 and the gate electrode 8 can be 4 μm. The above preferred parameters can achieve optimal device performance.

[0059] In order to facilitate understanding of the effect of the anti-single particle radiation reinforced gallium nitride high electron mobility transistor in the embodiment of the present application, the principle thereof is described below.

[0060] The existing reinforcement structure introduces additional electrodes, generates additional parasitic capacitance or has low anti-radiation performance, the anti-radiation structure of the present application avoids the above problems by doping in the device, so that the present application has high anti-radiation performance and high output current at the same time.

[0061] Specifically, the P-type GaN layer 5 between the gate electrode 8 and the drain electrode 7 raises the conduction band level of the heterojunction, so that a partial depletion region is formed near the P-type GaN layer 5 and the N-type AlGaN layer 3 when the device is in an off state. Due to the back channel effect, a large number of electrons generated from the source electrode 9 can only pass through the GaN buffer layer 2 near the P-type GaN layer 5 and the N-type AlGaN layer 3, and finally reach the drain electrode 7. Since the GaN buffer layer 2 contains a large number of acceptor defects, the number of electrons reaching the drain electrode 7 is reduced during the movement of the electrons to the drain electrode 7, and the transient current of the device is reduced.

[0062] The N-type AlGaN layer 3 can compensate the two-dimensional electron gas in the channel and improve the output current of the device. At the same time, the P-type GaN layer 5 and the N-type AlGaN layer 3 will jointly reduce the internal electric field of the device, weaken the impact ionization in the device, reduce the generation of electron-hole pairs, and reduce the single particle transient current.

[0063] The present application changes the internal structure of the device and dopes at a suitable position, so that it has high anti-radiation performance. Since the design is made inside the device, no additional parasitic capacitance is introduced, the high frequency characteristics of the device are not affected, and the design and application of the device in the circuit are not affected. Under the joint action of P-type doping and N-type doping, the internal electric field of the device is weakened as a whole, the radiation reliability of the device is enhanced, and the N-type doping makes the device have high output current. The present application avoids the problems brought by the previous reinforcement structure, so that the device has high anti-radiation performance and still has good output characteristics, and the radiation reliability of the device is improved.

[0064] Compared with the existing anti-radiation reinforcement device technology, the present application has the following advantages:

[0065] (1) The P-type GaN layer is located at the barrier layer (i.e. the AlGaN barrier layer) between the gate and the drain, which raises the energy band of the AlGaN side and does not affect the high frequency characteristics of the device, so that the device has high anti-radiation performance without increasing the metal electrode area to generate additional parasitic capacitance. This structure can effectively avoid the problems of increased parasitic capacitance and degraded high frequency characteristics of the double field plate structure device;

[0066] (2) The N-type AlGaN layer can compensate the two-dimensional electron gas in the channel, and improve the output current. The P-type GaN layer and the N-type AlGaN layer jointly weaken the internal electric field of the device, reduce the generation of hole-electron pairs, and reduce the single event transient current;

[0067] (3) The present application does not introduce an additional electrode, optimizes the device structure, and makes the circuit design simpler. The device can meet the actual application well while still having high radiation resistance. The structure can effectively avoid the problem that the introduction of an additional ground electrode in the Schottky metal structure makes the device structure complex and increases the difficulty of circuit design;

[0068] (4) By changing the position structure parameters and doping concentration of the P-type GaN layer and the N-type AlGaN layer, high radiation resistance and output characteristics can be achieved, the radiation reliability of the device is ensured, and the application field of the device is more extensive.

[0069] In a second aspect, an embodiment of the present application provides a preparation method of a single event radiation hardened gallium nitride high electron mobility transistor, please refer to Figure 2 , the method comprises the following steps:

[0070] S1, on a Si substrate, a GaN buffer layer is epitaxially grown by a metal organic chemical vapor deposition method;

[0071] This step can be understood by referring to Figure 3a and Figure 3b . The thickness of the Si substrate and the GaN buffer layer can be selected as needed.

[0072] In a preferred embodiment, the thickness of the GaN buffer layer can be 1.945 μm.

[0073] S2, a first recess is made at a local position of the top layer of the grown GaN buffer layer by an etching process, AlGaN is grown in the first recess by a metal organic chemical vapor deposition method, and an N-type AlGaN layer is generated by ion implantation;

[0074] This step can be understood by referring to Figure 3c and Figure 3d .

[0075] The upper surface of the N-type AlGaN layer is flush with the upper surface of the surrounding GaN buffer layer, and the position of the N-type AlGaN layer is close to one side edge of the GaN buffer layer and is not in the center position.

[0076] The thickness and doping concentration of the N-type AlGaN layer can be selected as needed. In a preferred embodiment, when the N-type AlGaN layer is generated by ion implantation, the doping concentration is 1×10 18 cm -3The thickness of the N-type AlGaN layer can be 0.01 μm.

[0077] S3, epitaxially growing an AlGaN barrier layer on the whole surface of the GaN buffer layer by a metal organic chemical vapor deposition method;

[0078] This step can be understood by referring to Figure 3e understanding.

[0079] The AlGaN barrier layer is located on the upper surface of the GaN buffer layer and the N-type AlGaN layer, and the thickness thereof can be set as required. In a preferred embodiment, the thickness of the AlGaN barrier layer can be 0.015 μm.

[0080] S4, making a second groove in the grown AlGaN barrier layer at a position opposite to the N-type AlGaN layer by an etching process, wherein the lower surface of the second groove contacts the upper surface of the N-type AlGaN layer, and the width of the second groove is smaller than that of the first groove;

[0081] This step can be understood by referring to Figure 3f understanding.

[0082] S5, after growing a GaN layer in the second groove by a metal organic chemical vapor deposition method, performing Mg ion doping by an ion implantation process to generate a P-type GaN layer;

[0083] This step can be understood by referring to Figure 3g understanding.

[0084] In the embodiment of the present application, when the P-type GaN layer is generated by performing Mg ion doping by an ion implantation process, the doping concentration can be 1×1018cm-2. 16 -3 The thickness of the P-type GaN layer is the same as that of the AlGaN barrier layer. Similarly, in a preferred embodiment, the thickness of the P-type GaN layer can be 0.015 μm;

[0085] S6, depositing SiN on the surface where the AlGaN barrier layer and the P-type GaN layer are located by a PECVD (Plasma Enhanced Chemical Vapor Deposition) process, and generating a SiN passivation layer by high-temperature annealing;

[0086] This step can be understood by referring to Figure 3h understanding.

[0087] In this step, the temperature of the high-temperature annealing can be 500 ℃, and the annealing time can be 20 min.

[0088] ​S7, defining source electrode region, drain electrode region and gate electrode region by photolithography process, removing SiN passivation layer of source electrode region, drain electrode region and gate electrode region by etching process, obtaining source electrode position, drain electrode position and gate electrode position;

[0089] The step can be seen from Figure 3i understood.

[0090] In the source electrode region, drain electrode region and gate electrode region defined by the photolithography process,

[0091] The drain electrode region is located outside the laminated structure of the AlGaN barrier layer, the P-type GaN layer and the SiN passivation layer, and is close to one side of the P-type GaN layer.

[0092] The source electrode region is located on the other side of the laminated structure.

[0093] The gate electrode region is located in the SiN passivation layer and above the AlGaN barrier layer, close to one side of the source electrode region.

[0094] S8, depositing corresponding metals at the source electrode position, the drain electrode position and the gate electrode position by metal evaporation, and the metals deposited at the source electrode and the drain electrode position form source and drain electrode ohmic contact after high-temperature annealing, and the metal deposited at the gate electrode position directly forms Schottky contact.

[0095] The metal deposited at the source electrode position can be Ti / Al / Ni / Au multilayer metal, the metal deposited at the drain electrode position can be Ti / Al / Ni / Au multilayer metal, and the metal deposited at the gate electrode position can be Ni / Au multilayer metal.

[0096] The temperature used for high-temperature annealing of the metal deposited at the source electrode and the drain electrode position can be 840 DEG C, and the annealing time can be 30s.

[0097] The device structure formed by the above processing can be seen from Figure 3j understood, wherein S represents the source electrode, G represents the gate electrode, and D represents the drain electrode.

[0098] The preparation method of the anti-single particle radiation reinforced gallium nitride high electron mobility transistor provided by the embodiment of the application generates an N-type AlGaN layer below the barrier layer between the gate and the drain, so that the output current is improved; by generating a P-type GaN layer and an N-type AlGaN layer between the source and the drain, the conduction band level is raised, the injection of electrons from the source to the buffer layer in the off state is blocked, and thus the buffer layer leakage current is reduced. At the same time, the internal electric field of the device can be weakened, the collision ionization of electron-hole pairs can be reduced, the single particle transient current can be reduced, the radiation resistance of the device is improved, the device structure is optimized, and the circuit design is simplified.

[0099] The application changes the barrier structure by doping inside the device, hinders the movement of electrons inside the device, increases the time of collecting electrons, thereby reducing the single particle transient current. The application changes the structure inside the device, does not affect the design and use of the device in the actual circuit, improves the anti-radiation performance of the device without affecting the circuit design.

[0100] The application changes the barrier structure by doping inside the device, hinders the movement of electrons inside the device, increases the time of collecting electrons, thereby reducing the single particle transient current. The application changes the structure inside the device, does not affect the design and use of the device in the actual circuit, improves the anti-radiation performance of the device without affecting the circuit design.

[0101] The application does not introduce additional electrodes, simplifies the circuit design, only performs doping inside the device, does not generate additional parasitic capacitance, avoids the problem of unstable device characteristics. The P-type GaN layer and the N-type AlGaN layer in contact with the upper and lower surfaces can also reduce the electric field, reduce the collision ionization inside the device, reduce the generation of electron-hole pairs, and realize the anti-radiation reinforcement performance of the gallium nitride-based HEMT device.

[0102] It should be noted that in the description of the application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0103] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0104] In the description of the specification, reference to "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" means that a particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the application. The appearances of the phrases "in one embodiment", "in some embodiments", "an example", "a specific example", or "some examples" in various places in the specification are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples. Also, the terminology used in the description is for the purpose of describing particular embodiments only and is not intended to be limiting. It is also possible in the present application that additional or

[0105] The above descriptions are only the preferred embodiment of the application, not intended to limit the protection scope of the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A gallium nitride high electron mobility transistor hardened against single event radiation, characterized in that: include: Si substrate (1), a GaN buffer layer (2) arranged on the Si substrate (1), an N-type AlGaN layer (3) arranged at a local position of the top layer in the GaN buffer layer (2), an AlGaN barrier layer (4) arranged on the GaN buffer layer (2) and the N-type AlGaN layer (3), a P-type GaN layer (5) arranged above the N-type AlGaN layer (3) and inside the AlGaN barrier layer (4), a SiN passivation layer (6) arranged on the AlGaN barrier layer (4) and the P-type GaN layer (5), and a drain electrode (7), a gate electrode (8), and a source electrode (9); The drain electrode (7) is located outside the stacked structure formed by the AlGaN barrier layer (4), the P-type GaN layer (5), and the SiN passivation layer (6), on one side close to the P-type GaN layer (5), and the source electrode (9) is located outside the stacked structure; the gate electrode (8) is located inside the SiN passivation layer (6), on the side above the AlGaN barrier layer (4) close to the source electrode (9); the lower surface of the P-type GaN layer (5) contacts the upper surface of the N-type AlGaN layer (3), and the width of the P-type GaN layer (5) is smaller than the width of the N-type AlGaN layer (3).

2. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The thickness of the GaN buffer layer (2) is 1.945 μm.

3. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The doping concentration of the N-type AlGaN layer (3) is 1×10 18 cm -3 , thickness is 0.01μm.

4. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The thickness of the AlGaN barrier layer (4) is 0.015 μm.

5. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The doping concentration of the P-type GaN layer (5) is 1×10 16 cm -3 , thickness is 0.015μm.

6. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The distance between the source electrode (9) and the drain electrode (7) is 1.5 μm.

7. The single event radiation hardened gallium nitride high electron mobility transistor according to claim 1, wherein: The distance between the source electrode (9) and the gate electrode (8) is 4 μm.

8. A method for preparing a single-event radiation-hardened gallium nitride high electron mobility transistor, characterized in that: include: On the Si substrate, a GaN buffer layer is epitaxially grown by metal organic chemical vapor deposition; Forming a first groove at a local position of the top layer of the grown GaN buffer layer by an etching process, growing AlGaN in the first groove by metal organic chemical vapor deposition, and performing ion implantation to form an N-type AlGaN layer; Epitaxially growing an AlGaN barrier layer on the entire surface of the GaN buffer layer by metal organic chemical vapor deposition; forming a second groove by etching at a position in the grown AlGaN barrier layer facing the N-type AlGaN layer, wherein a lower surface of the second groove contacts an upper surface of the N-type AlGaN layer, and a width of the second groove is smaller than a width of the first groove; After growing GaN in the second groove by metal organic chemical vapor deposition, Mg ion doping is performed by ion implantation to form a P-type GaN layer; Depositing SiN on the surface of the AlGaN barrier layer and the P-type GaN layer by a PECVD process, and forming a SiN passivation layer by high-temperature annealing; The source electrode region, the drain electrode region, and the gate electrode region are defined by a photolithography process, and the SiN passivation layer of the source electrode region, the drain electrode region, and the gate electrode region is removed by an etching process to obtain the source electrode position, the drain electrode position, and the gate electrode position; Corresponding metals are deposited at the source electrode, the drain electrode and the gate electrode by metal evaporation. The metals deposited at the source electrode and the drain electrode form ohmic contacts of the source and drain electrodes after high-temperature annealing, and the metal deposited at the gate electrode directly forms a Schottky contact.

9. The method for preparing a single event radiation hardened gallium nitride high electron mobility transistor according to claim 8, characterized in that: In the source electrode region, drain electrode region and gate electrode region defined by the photolithography process, The drain electrode region is located outside the stacked structure consisting of the AlGaN barrier layer, the P-type GaN layer, and the SiN passivation layer, and is close to one side of the P-type GaN layer; The source electrode region is located on the other side outside the stacked structure; The gate electrode region is located in the SiN passivation layer and above the AlGaN barrier layer on a side close to the source electrode region.

10. The method for preparing a single event radiation hardened gallium nitride high electron mobility transistor according to claim 8, wherein: When ion implantation is performed to generate an N-type AlGaN layer, the doping concentration is 1×10 18 cm -3 ; When Mg ions are doped by ion implantation to generate a P-type GaN layer, the doping concentration is 1×10 16 cm -3 .

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