Hydrogen terminal diamond metal oxide semiconductor field effect transistor (MOSFET) / enhanced gallium nitride high electron mobility transistor (HEMT) monolithic integrated complementary circuit and preparation method thereof

Abstract

The invention belongs to the technical field of semiconductor devices, and particularly relates to a hydrogen terminal diamond MOSFET (Metal Oxide Semiconductor Field Effect Transistor) / enhanced gallium nitride HEMT (High Electron Mobility Transistor) monolithic integrated complementary circuit and a preparation method thereof. A p-type diamond MOSFET and an n-type enhanced gallium nitride HEMT are combined together through a heterogeneous integration method to prepare a logic complementary circuit; the technical problems that an n-type device is difficult to realize by diamond and a p-type device is difficult to realize by gallium nitride are effectively avoided; the monolithic integration of diamond / gallium nitride is beneficial to reducing the size of the device, improving the integration level and ensuring that the complementary circuit has high switching speed and low loss; the diamond is high in heat conductivity, the distribution of a heat generation field of the gallium nitride HEMT is modulated, the heat dissipation capability of the device is improved, and a solution is provided for application of a high-temperature CMOS (Complementary Metal Oxide Semiconductor).

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor devices, and in particular relates to a hydrogen-terminated diamond MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit and a preparation method thereof. Background Art

[0002] In recent years, in order to meet the needs of market applications, the replacement of semiconductor materials has been accelerating: from the first generation of semiconductor materials represented by silicon (Si) and germanium (Ge), to the second generation of semiconductor materials mainly based on gallium arsenide (GaAs), to the third generation of semiconductor materials such as gallium nitride (GaN) and silicon carbide (SiC), which are currently widely used, they are progressing towards a wider bandgap and a wider range of application scenarios. In recent years, ultra-wide bandgap semiconductor materials such as diamond with a wider bandgap have gradually entered everyone's field of vision.

[0003] Diamond has a large bandgap of 5.47 eV, a high breakdown field strength of 10 MV / cm, and a high carrier mobility of 4500 cm 2 / (V·s), hole 3800cm 2 / (V·s), high thermal conductivity 22W / (cm·K), more suitable for use in harsh environments. Studies have found that when hydrogen-terminated diamond treated with hydrogen plasma is exposed to air for a period of time, a layer of two-dimensional hole gas (2DHG) will form on its surface, showing p-type conductivity, and the hole concentration is generally 10 12 -10 14 cm -2 , the surface hole mobility is 20-680cm 2 ·V -1 ·s -1 The GaN HEMT (High Electron Mobility Transistor) structure has high electron mobility and can be used to prepare high-performance n-type field effect transistors. However, the thermal conductivity of GaN material is extremely low, only 130W / m·K, and in practical applications, the device performance will be reduced due to thermal effects.

[0004] As an important component in logic circuit applications, the design of CMOS inverters (Complementary Metal-Oxide-Semiconductor) has always been a research hotspot. In applications, CMOS inverters have the advantages of low static power consumption, large output swing, and strong anti-interference ability. However, diamond itself is difficult to achieve the problem of n-type devices required for the preparation of CMOS devices. New material systems and device structures are needed to solve the current problems of integrated circuit applications faced by diamond and the heat dissipation problems faced by CMOS devices. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithic integrated complementary circuit and preparation method, which utilizes the two-dimensional hole gas channel on the surface of the hydrogen terminal and the two-dimensional electron gas channel of gallium nitride to respectively realize p-type conductive channel and n-type conductive channel enhancement transistors, thereby realizing a complementary circuit in diamond / gallium nitride heterogeneous integration.

[0006] The present invention is specifically achieved through the following technical solutions.

[0007] The present invention provides a hydrogen-terminated diamond MOSFET / enhanced gallium nitride HEMT monolithically integrated complementary circuit, which is essentially a CMOS device, including a diamond substrate, an intermediate layer is arranged on one side of the surface of the diamond substrate, and an enhanced gallium nitride HEMT structure is arranged on the intermediate layer;

[0008] A hydrogen-terminated diamond is arranged on the other side of the surface of the diamond substrate, oxygen-terminated diamonds are arranged on the diamond substrate and at both ends of the hydrogen-terminated diamond, a second source electrode is arranged on one side of the surface of the hydrogen-terminated diamond, and a second drain electrode is arranged on the other side, a second dielectric layer is arranged on the surface of the hydrogen-terminated diamond, a second gate electrode is arranged on the second dielectric layer, and the second dielectric layer and the second gate electrode are both located between the second source electrode and the second drain electrode;

[0009] The hydrogen-terminated diamond serves as a p-type conductive channel, the gallium nitride HEMT structure serves as an n-type conductive channel, and carriers migrate in the p-type conductive channel and the n-type conductive channel.

[0010] Wherein, the enhancement mode gallium nitride HEMT structure is a recessed gate gallium nitride HEMT structure, or the enhancement mode gallium nitride HEMT structure is a p-GaN gate structure gallium nitride HEMT structure.

[0011] In a preferred embodiment of the present invention, when the enhancement-mode gallium nitride HEMT structure is a recessed gate gallium nitride HEMT structure, the recessed gate gallium nitride HEMT structure includes a gallium nitride HEMT structure, a passivation layer, a first dielectric layer, a first source electrode, a first drain electrode and a first gate electrode, the gallium nitride HEMT structure is located on the intermediate layer, a gate recess is opened on the surface of the gallium nitride HEMT structure, the passivation layer is arranged on the surface of the gallium nitride HEMT structure and outside the gate recess, the first dielectric layer is arranged on the passivation layer and the surface of the gate recess, and the first gate electrode is located in the gate recess region on the first dielectric layer; a first source electrode is arranged on one side of the surface of the gallium nitride HEMT structure, and a first drain electrode is arranged on the other side, and the first gate electrode, the first dielectric layer and the passivation layer are all located between the first source electrode and the first drain electrode; the first drain electrode and the second drain electrode are metal interconnected through a first interconnection line, and the first gate electrode and the second gate electrode are metal interconnected through a second interconnection line.

[0012] In a preferred embodiment of the present invention, when the enhancement-mode gallium nitride HEMT structure is a p-GaN gate structure gallium nitride HEMT structure, the p-GaN gate structure gallium nitride HEMT structure includes a gallium nitride HEMT structure, a surface layer of the gallium nitride HEMT structure is configured as a p-GaN cap layer, the p-GaN cap layer on the surface layer of the gallium nitride HEMT structure except for a gate region is etched or passivated, and a p-GaN layer is formed in the gate region, a first gate electrode is arranged on the p-GaN layer, a first source electrode and a first drain electrode are respectively arranged on both sides of the etched or passivated region of the gallium nitride HEMT structure, and the first gate electrode is located between the first source electrode and the first drain electrode; the first drain electrode and the second drain electrode are metal interconnected through a first interconnection line, and the first gate electrode and the second gate electrode are metal interconnected through a second interconnection line.

[0013] In a preferred embodiment of the present invention, the material of the diamond substrate is homogeneous or heterogeneous diamond prepared by high temperature and high pressure (HPHT) technology or vapor phase epitaxy CVD technology, including single crystal diamond;

[0014] The intermediate layer material includes but is not limited to amorphous carbon, SiO2, AlN, SiN x , BN, thickness is 5 to 200 nm;

[0015] The GaN HEMT structure includes, from bottom to top, but is not limited to, a GaN or AlGaN buffer layer, a GaN channel layer, an AlN spacer layer, an AlGaN barrier layer, and a GaN cap layer;

[0016] The material of the passivation layer includes SiN x , SiO2, thickness is 10~500nm;

[0017] The first source electrode and the first drain electrode are made of the same material, including Ti, Al, Ni and Au from bottom to top, with a thickness of 20 nm for Ti, 150 nm for Al, 30 to 40 nm for Ni, and 50 to 80 nm for Au;

[0018] The material of the first dielectric layer includes SiN x , SiO2, Al2O3, thickness is 10~500nm;

[0019] The material of the first gate electrode includes Ni and Au from bottom to top, the Ni thickness is 30nm, and the Au thickness is 200nm;

[0020] The two-dimensional hole density of the hydrogen-terminated diamond (i.e., the surface carrier concentration in the p-type conductive channel) is 1×10 12 ~5×10 14 cm -2 , the mobility is 20~2500cm 2 / (V·s), the thickness of the hydrogen-terminated diamond is 1 to 20 nm;

[0021] The second source electrode and the second drain electrode are made of the same material, including one or more of Au, Pd, Ir, Pt, Ti, and Ni, and have a thickness of 50 to 500 nm;

[0022] The material of the second dielectric layer includes one or more of Al2O3, TiO2, and MoO3, and the thickness is 10 to 500 nm;

[0023] The material of the second gate electrode includes one or more of Al, Zr, Hf, and Mo, and the thickness is 50-500 nm.

[0024] When the enhancement-mode gallium nitride HEMT structure is a recessed gate gallium nitride HEMT structure, the method for preparing the above-mentioned hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit comprises the following steps:

[0025] Step 1, providing a sample, including a diamond substrate, an intermediate layer and a gallium nitride HEMT structure;

[0026] Step 2: using etching technology to remove the GaN HEMT structure and the middle layer on one side until the diamond substrate is exposed, and at the same time forming a GaN HEMT device mesa structure to achieve device isolation;

[0027] Step 3, depositing a passivation layer on the sample surface;

[0028] Step 4, using photolithography and etching technology, remove the passivation layer in the source and drain electrode regions of the GaN HEMT structure to expose the source and drain electrode regions, and remove the passivation layer on the other side of the diamond substrate;

[0029] Step 5, using a deposition technique, depositing a first source electrode and a first drain electrode ohmic contact respectively in the source and drain electrode regions of the GaN HEMT structure, followed by annealing;

[0030] Step 6, using photolithography and etching technology, etching the passivation layer under the gate region and the AlGaN barrier layer of the GaN HEMT structure to form a gate groove;

[0031] Step 7, depositing a protective layer on the GaN HEMT structure and performing a hydrogenation treatment on the other side of the diamond substrate to form hydrogen-terminated diamond, while repairing the diamond and AlGaN lattices damaged by etching;

[0032] Step 8, using photolithography and deposition technology, depositing a second source electrode and a second drain electrode ohmic contact at both ends of the hydrogen terminal diamond;

[0033] Step 9, performing oxygen termination treatment on the surfaces of both sides of the diamond to form oxygen-terminated diamond to achieve device isolation;

[0034] Step 10, removing the protective layer on the gallium nitride HEMT structure, depositing a first dielectric layer on the passivation layer and the surface of the gate groove by using photolithography and deposition technology, and depositing a second dielectric layer on the hydrogen-terminated diamond;

[0035] Step 11, depositing a first gate electrode on the gate groove region by using photolithography and deposition technology;

[0036] Step 12, depositing a second gate electrode in the middle area between the second source electrode and the second drain electrode on the second dielectric layer, and at the same time depositing a first interconnection line and a second interconnection line on the sample, so that the first drain electrode and the second drain electrode are metal interconnected through the first interconnection line, and the first gate electrode and the second gate electrode are metal interconnected through the second interconnection line.

[0037] In a preferred embodiment of the present invention, in step 1, the connection method between the diamond substrate and the gallium nitride HEMT structure includes bonding of diamond and the gallium nitride HEMT structure, epitaxial growth of the gallium nitride HEMT structure on single crystal diamond, or epitaxial growth of single crystal diamond on the gallium nitride HEMT structure.

[0038] In a preferred embodiment of the present invention, the etching technology in step 2, step 4 and step 6 is to use inductively coupled plasma etching, with a plasma power of 50 to 1000 W and a rate of 1 to 1000 nm / min;

[0039] In a preferred embodiment of the present invention, in step 5, the annealing conditions are: the annealing atmosphere is N2, the annealing temperature is 750°C to 900°C, and the annealing time is 25 to 180s;

[0040] In a preferred embodiment of the present invention, the protective layer material in step 7 is SiO2 or SiN x , thickness is 100~500nm; hydrogenation treatment uses MPCVD equipment, H2 flow rate is 50~1000sccm, treatment temperature is 500~900℃, and treatment time is 10s to 2h;

[0041] In a preferred embodiment of the present invention, the oxygen terminal treatment in step 9 specifically includes: using ultraviolet rays or ozone, oxygen plasma to treat the diamond surface, wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 min.

[0042] In a preferred embodiment of the present invention, the deposition methods involved in steps 1 to 12 include plasma enhanced chemical vapor deposition (PECVD), low pressure chemical vapor deposition (LPCVD), atomic layer deposition (ALD), electron beam evaporation or sputtering; the lithography technology includes ultraviolet lithography, electron beam lithography or step-by-step non-contact lithography.

[0043] When the enhancement-mode gallium nitride HEMT structure is a p-GaN gate structure gallium nitride HEMT structure, the method for preparing the above-mentioned hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit comprises the following steps:

[0044] A sample is provided, comprising a diamond substrate, an intermediate layer and a gallium nitride HEMT structure; the connection method between the diamond substrate and the gallium nitride HEMT structure comprises bonding of diamond and the gallium nitride HEMT structure, epitaxy of the gallium nitride HEMT structure on a single crystal diamond, or epitaxy of a single crystal diamond on the gallium nitride HEMT structure;

[0045] The gallium nitride HEMT structure and the middle layer on one side are removed by etching technology until the diamond substrate is exposed, and at the same time, the mesa structure of the gallium nitride HEMT device is formed to achieve device isolation;

[0046] Using etching or plasma treatment technology, etching or passivating the p-GaN cap layer on the surface of the GaN HEMT structure, leaving only the p-GaN layer in the gate area;

[0047] Using photolithography and deposition technology, a first source electrode and a first drain electrode ohmic contact are deposited at both ends of the gallium nitride HEMT structure, followed by annealing; the annealing conditions are: annealing atmosphere is N2, annealing temperature is 750° C. to 900° C., and annealing time is 25s to 180s;

[0048] A protective layer is deposited on the GaN HEMT structure, and a hydrogenation treatment is performed on one side of the diamond substrate to form hydrogen-terminated diamond, while repairing the diamond and AlGaN lattices damaged by etching; the protective layer material is SiO2, SiN x , thickness is 100~500nm, hydrogenation treatment uses MPCVD equipment, H2 flow rate is 50~1000sccm, treatment temperature is 500~900℃, and treatment time is 10s to 2h;

[0049] The surfaces on both sides of the diamond are oxygen-terminated to form oxygen-terminated diamond to achieve device isolation; the oxygen-terminated treatment specifically includes: using ultraviolet light or ozone or oxygen plasma to treat the diamond surface, wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 minutes.

[0050] forming a second source electrode, a second drain electrode, a second dielectric layer, and a second gate electrode on the hydrogen-terminated diamond;

[0051] Using photolithography and deposition technology, a first gate electrode is deposited on the p-GaN layer, and then a first interconnection line and a second interconnection line are deposited on the sample to achieve metal interconnection between the first drain electrode and the second drain electrode through the first interconnection line, and metal interconnection between the first gate electrode and the second gate electrode through the second interconnection line.

[0052] In a preferred embodiment of the present invention, the deposition method involved includes plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atomic layer deposition, electron beam evaporation or sputtering; the photolithography technology includes ultraviolet lithography, electron beam lithography or step-by-step non-contact lithography.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] The hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit of the present invention is essentially a CMOS device. A p-type diamond MOSFET and an n-type enhancement-mode gallium nitride HEMT structure (including a groove gate gallium nitride HEMT structure or a p-GaN gate structure gallium nitride HEMT structure) are combined together by a heterogeneous integration method to prepare a logic complementary circuit, which effectively avoids the technical difficulties that it is difficult to realize n-type devices with diamond and difficult to realize p-type devices with gallium nitride; the monolithic integration of diamond / gallium nitride is conducive to reducing the device volume, improving the integration level, and ensuring that the complementary circuit has a high switching speed and low loss; diamond has high thermal conductivity and simultaneously modulates the heat generation field distribution of the gallium nitride HEMT, thereby improving the heat dissipation capacity of the device, providing a solution for high-temperature CMOS applications.

[0055] The CMOS device of the present invention utilizes the complementary characteristics of the p-type diamond MOSFET and the n-type enhanced gallium nitride HEMT structure to realize logic inversion, and controls the output signal by controlling the input signal. It has multiple functions in digital system design, computer processors and communication circuits, including logic gate implementation, clock signal driving, buffer amplifier, signal inversion control and digital signal processing, etc., which promotes the development of digital circuit technology and provides an efficient and reliable working basis for digital systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 The present invention is a schematic diagram of a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit; Figure 1 In the figure, diamond substrate 1; intermediate layer 2; gallium nitride HEMT structure 3; hydrogen-terminated diamond 4; oxygen-terminated diamond 5; passivation layer 6; first source electrode 7; first drain electrode 8; first dielectric layer 9; first gate electrode 10; second source electrode 11; second drain electrode 12; second dielectric layer 13; second gate electrode 14; first interconnection line 15; second interconnection line 16.

[0057] Figure 2 The present invention is a flow chart of a method for preparing a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit.

[0058] Figure 3 It is a top view of a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit of the present invention.

[0059] Figure 4 yes Figure 2 Three preparation processes of diamond / gallium nitride heterogeneous integrated substrate in the preparation method.

[0060] Figure 5 The present invention is a schematic diagram of a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated complementary circuit; Figure 5 In the figure, diamond substrate 1; intermediate layer 2; gallium nitride HEMT structure 3; hydrogen-terminated diamond 4; oxygen-terminated diamond 5; first source electrode 7; first drain electrode 8; p-GaN layer 17; first gate electrode 10; second source electrode 11; second drain electrode 12; second dielectric layer 13; second gate electrode 14; first interconnection line 15; second interconnection line 16.

[0061] Figure 6 It is a flow chart of a method for preparing a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated complementary circuit according to Example 4 of the present invention.

[0062] Figure 7 It is a top view of a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated complementary circuit of the present invention. DETAILED DESCRIPTION

[0063] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0064] In order to solve the current integrated circuit application problems faced by diamond and the thermal problems faced by CMOS devices, the present invention combines p-type diamond MOSFET and n-type enhancement-mode gallium nitride HEMT structures together through a heterogeneous integration method to prepare a logic complementary circuit, effectively avoiding the technical difficulty that diamond is difficult to achieve in preparing n-type devices required for CMOS devices; the monolithic integration of diamond / gallium nitride is conducive to reducing the device volume, improving the integration level, and ensuring that the complementary circuit has a high switching speed and low loss; diamond has high thermal conductivity and modulates the heat generation field distribution of GaN HEMT at the same time, improving the device's heat dissipation capability, and providing a solution for high-temperature CMOS applications.

[0065] The n-type enhancement-mode gallium nitride HEMT structure in the present invention may adopt a recessed gate gallium nitride HEMT structure, or may adopt a p-GaN gate structure gallium nitride HEMT structure.

[0066] When using a recessed gate GaN HEMT structure, please refer to Figure 1 and Figure 3 As shown, it includes a diamond substrate 1, an intermediate layer 2, a gallium nitride HEMT structure 3, a hydrogen-terminated diamond 4, an oxygen-terminated diamond 5, a passivation layer 6, a first source electrode 7, a first drain electrode 8, a first dielectric layer 9, a first gate electrode 10, a second source electrode 11, a second drain electrode 12, a second dielectric layer 13, a second gate electrode 14, a first interconnection line 15, and a second interconnection line 16.

[0067] The gallium nitride HEMT structure 3 is located on one side of the diamond substrate 1, the intermediate layer 2 is located between the diamond substrate 1 and the gallium nitride HEMT structure 3, the first source electrode 7 is located on one side of the gallium nitride HEMT structure 3, the first drain electrode 8 is located on the other side of the gallium nitride HEMT structure 3, the passivation layer 6 is located on the upper surface of the gallium nitride HEMT structure 3, the first dielectric layer 9, the passivation layer 6, and the first gate electrode 10 are all located between the first source electrode 7 and the first drain electrode 8, and the first gate electrode 10 is located in the gate groove region on the first dielectric layer 9; the hydrogen-terminated diamond 4 is located on the other side of the diamond substrate 1, and the first source electrode 7 is located on the diamond substrate 1. Oxygen-terminated diamonds 5 are respectively arranged on a stone substrate 1 and at both ends of a hydrogen-terminated diamond 4, the second source electrode 11 is located on one side of the hydrogen-terminated diamond 4, the second drain electrode 12 is located on the other side of the hydrogen-terminated diamond 4, the second dielectric layer 13 covers the upper surface of the hydrogen-terminated diamond 4, the second gate electrode 14 is located on the second dielectric layer 13, and the second dielectric layer 13 and the second gate electrode 14 are both located between the second source electrode 11 and the second drain electrode 12; the first drain electrode 8 and the second drain electrode 12 are metal-interconnected through a first interconnect line 15, and the first gate electrode 10 and the second gate electrode 14 are metal-interconnected through a second interconnect line 16.

[0068] The diamond substrate 1 is used as the substrate of the entire CMOS device. On the one hand, it is used as a p-type enhancement device, and on the other hand, it can provide good heat dissipation. The middle layer 2 is a composite layer of the diamond substrate and the HEMT structure. The gallium nitride HEMT structure 3 is the material basis for forming an n-type enhancement device (i.e., an n-type conductive channel). The hydrogen-terminated diamond 4 is used as a conductive channel for a p-type enhancement device (i.e., a p-type conductive channel). The oxygen-terminated diamond 5 is used for device isolation, similar to the mesa etching of the HEMT device. The passivation layer 6 protects the surface of the HEMT device and reduces The first source electrode 7 and the first drain electrode 8 are ohmic contacts, providing voltage for both ends of the n-type conductive channel; the first dielectric layer 9 is used to improve gate control and reduce gate leakage current; the first gate electrode 10 provides gate voltage to regulate the n-type conductive channel current; the second source electrode 11 and the second drain electrode 12 have the same functions as the first source electrode 7 and the first drain electrode 8; the second dielectric layer 13 has the same functions as the first dielectric layer 9; the second gate electrode 14 has the same functions as the first gate electrode 10; the first interconnection line 15 and the second interconnection line 16 are used to form a logic device.

[0069] The hydrogen-terminated diamond MOSFET is a p-type enhancement-mode device, and the recessed-gate gallium nitride HEMT structure is an n-type enhancement-mode device.

[0070] The material of the diamond substrate 1 includes single-crystal diamond.

[0071] The materials of the intermediate layer 2 include but are not limited to amorphous carbon, SiO2, AlN, SiN x , BN, thickness is 5 to 200 nm.

[0072] The GaN HEMT structure 3 includes but is not limited to a GaN or AlGaN buffer layer, a GaN channel layer, an AlN spacer layer, an AlGaN barrier layer, and a GaN cap layer; the material of the passivation layer 6 includes SiN x , SiO2, etc., with a thickness of 10 to 500 nm; the materials of the first source electrode 7 and the first drain electrode 8 include Ti, Al, Ni, and Au from bottom to top, with thicknesses of 20 nm, 150 nm, 30 to 40 nm, and 50 to 80 nm, respectively; the material of the first dielectric layer 9 includes SiN x , SiO2, Al2O3, etc., with a thickness of 10 to 500nm; the material of the first gate electrode 10 includes Ni and Au from bottom to top, with thicknesses of 30nm and 200nm respectively.

[0073] The thickness of the hydrogen-terminated diamond 4 is 1 to 20 nm; the material of the second source electrode 11 and the second drain electrode 12 is the same, including one or more of Au, Pd, Ir, Pt, Ti, and Ni, with a thickness of 50 to 500 nm; the material of the second dielectric layer 13 includes one or more of Al2O3, TiO2, and MoO3, with a thickness of 10 to 500 nm; the material of the second gate electrode 14 includes one or more of Al, Zr, Hf, and Mo, with a thickness of 50 to 500 nm.

[0074] See also Figure 2 As shown, a method for preparing a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit of the present invention is carried out in sequence according to the following steps:

[0075] Step 1, providing a sample, including a diamond substrate 1, an intermediate layer 2 and a gallium nitride HEMT structure 3;

[0076] Step 2, using etching technology to remove the GaN HEMT structure 3 and the intermediate layer 2 on one side until the diamond substrate 1 is exposed, and at the same time, a GaN HEMT device mesa structure is formed to achieve device isolation;

[0077] Step 3, depositing a passivation layer 6 on the surface of the sample;

[0078] Step 4, using photolithography and etching technology, remove the passivation layer 6 in the source and drain electrode regions of the gallium nitride HEMT structure 3 to expose the source and drain electrode regions, and remove the passivation layer 6 on the other side of the diamond substrate 1 at the same time;

[0079] Step 5, using deposition technology, depositing the first source electrode 7 and the first drain electrode 8 ohmic contacts in the source and drain electrode regions of the gallium nitride HEMT structure 3, respectively, and then performing annealing;

[0080] Step 6, using photolithography and etching technology, etching the passivation layer 6 under the gate region and a portion of the AlGaN barrier layer of the gallium nitride HEMT structure 3 to form a gate groove;

[0081] Step 7, depositing a protective layer on the gallium nitride HEMT structure, and performing a hydrogenation treatment on one side of the diamond substrate 1 to form a hydrogen-terminated diamond 4, while repairing the diamond and aluminum gallium nitride lattices damaged by etching;

[0082] Step 8, using photolithography and deposition technology, deposit the second source electrode 11 and the second drain electrode 12 at both ends of the hydrogen terminal diamond 4 to form ohmic contacts;

[0083] Step 9, performing oxygen termination treatment on the surfaces of both sides of the diamond substrate to form oxygen-terminated diamond 5 to achieve device isolation;

[0084] Step 10, removing the protective layer on the upper surface of the gallium nitride HEMT structure 3, depositing a first dielectric layer 9 on the passivation layer 6 and the surface of the gate groove by using photolithography and deposition technology, and depositing a second dielectric layer 13 on the hydrogen-terminated diamond;

[0085] Step 11, depositing a first gate electrode 10 on the gate groove region by using photolithography and deposition technology;

[0086] Step 12, depositing a second gate electrode 14 in the middle area between the second source electrode 11 and the second drain electrode 12 on the second dielectric layer 13, depositing a first interconnection line 15 and a second interconnection line 16 on the sample, so that the first drain electrode 8 and the second drain electrode 12 are metal interconnected through the first interconnection line 15, and the first gate electrode 10 and the second gate electrode 14 are metal interconnected through the second interconnection line 16.

[0087] Wherein, in step 1, the connection method between the diamond substrate and the gallium nitride HEMT structure includes bonding of diamond and the gallium nitride HEMT structure, epitaxial growth of the gallium nitride HEMT structure on a single crystal diamond, or epitaxial growth of a single crystal diamond on the gallium nitride HEMT structure, corresponding to Figure 4 Method 1, Method 2 and Method 3 are shown.

[0088] The etching technology in step 2, step 4 and step 6 utilizes inductively coupled plasma etching, with a plasma power of 50 to 1000 W and a rate of 1 to 1000 nm / min.

[0089] Annealing conditions in step 5: annealing atmosphere is N2, annealing temperature is 750°C to 900°C, and annealing time is 25s to 180s.

[0090] The protective layer material in step 7 is SiO2, SiN x The thickness is 100-500nm; the hydrogen terminal treatment uses MPCVD equipment, the H2 flow rate is 50-1000sccm, the treatment temperature is 500-900℃, and the treatment time is 10s to 2h.

[0091] The oxygen terminal treatment in step 9 specifically includes: using ultraviolet rays or ozone or oxygen plasma to treat the diamond surface, wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 min.

[0092] The first drain electrode 8 and the second drain electrode 12 are interconnected through a first interconnection line 15, the first gate electrode 10 and the second gate electrode 14 are interconnected through a second interconnection line 16, the first source electrode 7 is grounded, and the second source electrode 11 is connected to a power supply voltage. Figure 3 shown.

[0093] The deposition methods described in the above steps include plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atomic layer deposition, electron beam evaporation or sputtering, etc.; the photolithography technology includes ultraviolet lithography, electron beam lithography or step-by-step non-contact lithography, etc.

[0094] The following embodiments define the materials of some components. In order to avoid confusion between numbers and letters, the reference numerals of the components are not marked.

[0095] Example 1

[0096] A method for preparing a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit comprises the following steps:

[0097] 1) providing a diamond substrate, epitaxially growing an AlN intermediate layer on the diamond substrate, epitaxially growing a gallium nitride substrate on the AlN intermediate layer using a metal organic chemical vapor deposition technique, and growing an epitaxial structure on the surface of the gallium nitride substrate, wherein the epitaxial structure includes a GaN channel layer, an AlN spacer layer, and an AlGaN barrier layer sequentially grown on the surface of the gallium nitride substrate, to form a gallium nitride HEMT structure;

[0098] 2) Using Al as a mask, photolithography and ICP processes are used to etch and remove the AlGaN barrier layer, AlN spacer layer, GaN channel layer, gallium nitride substrate and AlN intermediate layer on one side until the diamond substrate is exposed as an electronic-grade single-crystal diamond epitaxial layer substrate, and at the same time, a GaN HEMT device table is formed to achieve HEMT device isolation; the etching conditions are: the reaction gases are Cl2, BCl3 and Ar, and their flow rates are 80sccm, 10sccm and 5sccm respectively, and the RF powers of the upper electrode and the lower electrode are 1000W and 100W respectively; then the sample is placed in a hydrochloric acid solution for cleaning to completely remove the Al mask, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0099] 3) Use LPCVD equipment to deposit the passivation layer SiN on the AlGaN barrier layer x , thickness is 60nm, NH3 and SiH2Cl2 flow rates are 280sccm and 70sccm respectively, and the deposition temperature is 780℃;

[0100] 4) Use photolithography to form a patterned photoresist layer, and use RIE etching to remove the passivation layer SiN in the exposed diamond area and source and drain electrode area x , exposing the source and drain electrode areas, while removing the passivation layer on the other side of the diamond substrate. The etching conditions are: SF6 flow rate is 50sccm, O2 flow rate is 10sccm, chamber pressure is 11Pa, and RF power is 250W;

[0101] 5) forming source and drain electrode patterns by photolithography, and then placing the sample in an electron beam evaporator chamber, depositing four metals of titanium, aluminum, nickel and gold in sequence, with the thickness of the four metal layers being 20 nm, 150 nm, 30 nm and 50 nm respectively, and the first source electrode and the first drain electrode being made of the same material. After the evaporation, the sample is placed in an acetone solution for stripping, and the multiple layers of metal on the photoresist are removed; and then annealing is performed, with the annealing temperature being 900° C. and the annealing time being 30 s, to form ohmic contacts between the first source electrode and the first drain electrode;

[0102] 6) Using Al as a mask, forming a pattern by photolithography, and removing the AlGaN barrier layer under the gate region by ICP etching, the etching conditions are: the gas flow rates of Cl2 and BCl3 are 4sccm and 10sccm respectively, the chamber pressure is 0.5Pa, the RF power is 15W, and the etching rate is 6.5nm / min. Then, the sample is placed in an acetone solution for cleaning to remove the photoresist on the surface of the sample, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0103] 7) A 300nm SiO2 protective layer with a thickness of 200nm was deposited on one side of the GaN HEMT structure as a mask to protect the sample ohmic contact and active area. The sample was placed in the MPCVD chamber, and the microwave plasma power was controlled to make the chamber temperature 700℃. The hydrogen flow rate was maintained at 500sccm. The diamond substrate was hydrogenated and the lattice of the etched diamond and AlGaN surfaces was repaired. The treatment time was 20min, and a two-dimensional hole gas surface density of 2×10 13 cm -2 , the mobility is 150cm 2 / V·s of hydrogen-terminated diamond;

[0104] 8) Apply and spin photoresist on the sample, and bake it on a hot plate at 100°C for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form a source-drain electrode pattern on one side of the diamond; then place the sample in an electron beam evaporation chamber to deposit 150nm of Au, the second source electrode and the second drain electrode are made of the same material, and after the evaporation, place the sample in an acetone solution for stripping to form an ohmic contact between the second source electrode and the second drain electrode;

[0105] 9) Apply and spin photoresist on the sample and bake it on a 100°C hot plate for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds so that the photoresist covers the p-type conductive channel; place the sample in a UV / Ozone device and treat the sample for 15 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond;

[0106] 10) placing the sample in an RIE etcher, completely removing the SiO2 protective layer on the gallium nitride, and depositing a layer of Al2O3 on the sample by atomic layer deposition, with a thickness of 20 nm, a reaction chamber temperature of 200° C., a pressure of 1.2 torr, an aluminum source of trimethylaluminum, a flow rate of 300 sccm, and an oxygen source of ozone; using a photolithography process, covering the dielectric layer area with a photoresist, placing the sample in a phosphoric acid solution, and removing the Al2O3 outside the dielectric layer area; then placing the sample in an acetone solution, removing excess photoresist, and forming a first dielectric layer and a second dielectric layer;

[0107] 11) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist on the gate strip; then placing the sample in an electron beam evaporation chamber, depositing nickel and gold in sequence, with thicknesses of 30nm and 200nm respectively, and after the evaporation, placing the sample in an acetone solution for stripping, removing the multi-layer metal on the photoresist, and obtaining the first gate electrode;

[0108] 12) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for development for 80 seconds to remove the photoresist on the gate strip; then placing the sample in an electron beam evaporation machine chamber, depositing aluminum metal with a thickness of 100 nm, and after the evaporation, placing the sample in an acetone solution for stripping, removing the multi-layer metal on the photoresist, obtaining a second gate electrode, and depositing a first interconnection line and a second interconnection line of Al metal to achieve interconnection between the first drain electrode and the second drain electrode, as well as the first gate electrode and the second gate electrode.

[0109] Example 2

[0110] A method for preparing a hydrogen-terminated diamond MOSFET / recessed-gate gallium nitride HEMT monolithically integrated complementary circuit comprises the following steps:

[0111] 1) providing a diamond gallium nitride composite wafer, comprising a diamond substrate, an intermediate layer and a gallium nitride HEMT structure, wherein the gallium nitride HEMT structure is the same as the gallium nitride HEMT structure described in Example 1, and is prepared by epitaxially growing a single crystal diamond on the gallium nitride HEMT structure, wherein the specific steps include growing a 200 nm thick silicon nitride SiN on the gallium nitride surface by LPCVD; x as an intermediate layer; ultrasonically clean the gallium nitride / silicon nitride sample and dry it with an air gun; use the electrostatic self-assembly method for pretreatment, that is, heat the dried sample to 250°C and keep it in an oxygen-rich atmosphere for 100 minutes, then cool it naturally, and make the gallium nitride / silicon nitride sample carry a negative charge in the oxygen-rich atmosphere to complete the pretreatment; put the pretreated sample into MPCVD for single crystal diamond growth, using a mixed gas of hydrogen, methane and nitrogen to grow at 700°C, with a hydrogen ratio of 95%, a methane ratio of 2%, and a nitrogen ratio of 3%, and finally obtain a high-quality diamond gallium nitride composite wafer;

[0112] 2) Using Al as a mask, photolithography and ICP process are used to etch and remove the AlGaN barrier layer, AlN spacer layer, GaN channel layer, GaN substrate and SiN on one side. x The middle layer is formed until the diamond substrate is exposed as an electronic-grade single-crystal diamond epitaxial layer substrate, and at the same time, the GaN HEMT device table is formed to achieve HEMT device isolation; the etching conditions are: the reaction gases are Cl2, BCl3 and He, and their flow rates are 50sccm, 8sccm and 150sccm respectively, the reaction chamber pressure is 1500 mTorr, and the forward power is 200W; then the sample is placed in a hydrochloric acid solution for cleaning to completely remove the Al mask, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0113] 3) Use LPCVD equipment to deposit the passivation layer SiN on the AlGaN barrier layer x , thickness is 60nm, NH3 and SiH2Cl2 flow rates are 280sccm and 70sccm respectively, and the deposition temperature is 750℃;

[0114] 4) Use photolithography to form a patterned photoresist layer, and use RIE etching to remove the passivation layer SiN in the exposed diamond area and source and drain electrode area x , exposing the source and drain electrode areas, and removing the passivation layer on the other side of the diamond substrate at the same time. The etching conditions are: SF6 flow rate is 50sccm, O2 flow rate is 10sccm, chamber pressure is 11Pa, and RF power is 250W;

[0115] 5) forming source and drain electrode patterns by photolithography, and then placing the sample in an electron beam evaporator chamber, depositing titanium, aluminum, nickel and gold in sequence, with the thickness of the four metal layers being 20 nm, 150 nm, 40 nm and 80 nm respectively, and the first source electrode and the first drain electrode being made of the same material. After the evaporation, the sample is placed in an acetone solution for stripping, and the multiple layers of metal on the photoresist are removed; and then annealing is performed, with the annealing temperature being 750° C. and the annealing time being 30 s, to form ohmic contacts of the first source electrode and the first drain electrode;

[0116] 6) Using Al as a mask, photolithography was used to form a patterned mask layer, and ICP etching was used to remove the AlGaN barrier layer in the lower part of the gate region. The etching conditions were: the gas flow rates of Cl2 and BCl3 were 4 and 10 sccm respectively, the chamber pressure was 0.5 Pa, the RF power was 15 W, and the etching rate was 6.5 nm / min. After the Al mask was removed, the sample was placed in an acetone solution for cleaning, and then the sample was rinsed with ultrapure water and dried with nitrogen;

[0117] 7) A 500nm SiO2 protective layer with a thickness of 100nm was deposited on one side of the GaN HEMT structure as a mask to protect the sample ohmic contact and active area. The sample was placed in the MPCVD chamber, and the microwave plasma power was controlled to make the chamber temperature 850℃. The hydrogen flow rate was maintained at 100sccm, and the exposed diamond was hydrogenated. At the same time, the lattice of the etched diamond and the AlGaN surface was repaired. The processing time was 30min, and the two-dimensional hole gas surface density was 2×10 13 cm -2 , the mobility is 220cm 2 / V·s of hydrogen-terminated diamond;

[0118] 8) Apply and spin photoresist on the sample, and bake it on a hot plate at 100°C for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form a source-drain electrode pattern on one side of the diamond; then place the sample in an electron beam evaporation chamber, deposit 50nm and 100nm of Ti and Au in sequence, and the second source electrode and the second drain electrode have the same material. After the evaporation is completed, place the sample in an acetone solution for stripping to obtain an ohmic contact between the second source electrode and the second drain electrode;

[0119] 9) Applying and spinning photoresist on the sample, and baking it on a 100°C hot plate for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to form an isolation pattern; placing the sample in a UV / Ozone device and treating the sample for 20 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond; and then removing the photoresist on the sample surface using an acetone solution;

[0120] 10) Place the sample in an RIE etcher to completely remove the SiO2 protective layer on the gallium nitride; apply and spin photoresist on the sample, and bake it on a 100°C hot plate for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form a dielectric layer pattern; then place the sample in an electron beam evaporator chamber to deposit 20nm of HfO2, and after the evaporation, place the sample in an acetone solution for stripping to obtain a first dielectric layer and a second dielectric layer;

[0121] 11) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to form a gate electrode pattern; then placing the sample in an electron beam evaporation chamber, depositing nickel and gold in sequence, with thicknesses of 50nm and 200nm respectively, and placing the sample in an acetone solution for stripping after evaporation to remove the multiple layers of metal on the photoresist to obtain a first gate electrode;

[0122] 12) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for development for 80 seconds to form a gate dielectric layer pattern; placing the sample in an electron beam evaporator chamber, depositing 150nm of Al, and obtaining a second gate electrode after stripping, depositing a first interconnection line and a second interconnection line of Al metal, and realizing the interconnection between the first drain electrode and the second drain electrode, and the interconnection between the first gate electrode and the second gate electrode.

[0123] Based on the same inventive concept, the present invention also provides another implementation scheme. When a p-GaN gate structure gallium nitride HEMT structure is used, please refer to Figure 5 As shown, a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated complementary circuit of the present invention includes a diamond substrate 1, an intermediate layer 2, a gallium nitride HEMT structure 3, a hydrogen-terminated diamond 4, an oxygen-terminated diamond 5, a first source electrode 7, a first drain electrode 8, a first gate electrode 10, a second source electrode 11, a second drain electrode 12, a second dielectric layer 13, a second gate electrode 14, a first interconnection line 15, and a second interconnection line 16.

[0124] The gallium nitride HEMT structure 3 is located on one side of the diamond substrate 1 and includes a p-GaN layer 17 (the p-GaN layer 17 is used to form an enhancement mode device), that is, by etching or passivating the p-GaN cap layer on the surface of the gallium nitride HEMT structure 3, only the p-GaN layer 17 in the gate region is retained, the intermediate layer 2 is located between the diamond substrate 1 and the gallium nitride HEMT structure 3, the first source electrode 7 is located on one side of the gallium nitride HEMT structure 3, the first drain electrode 8 is located on the other side of the gallium nitride HEMT structure 3, and the first gate electrode 10 is located on the p-GaN layer 17; the hydrogen-terminated diamond 4 is located on the other side of the diamond substrate 1, and the first source electrode 7 is located on the other side of the diamond substrate 1. Oxygen-terminated diamonds 5 are respectively arranged on a diamond substrate 1 and at both ends of a hydrogen-terminated diamond 4, the second source electrode 11 is located on one side of the hydrogen-terminated diamond 4, the second drain electrode 12 is located on the other side of the hydrogen-terminated diamond 4, the second dielectric layer 13 covers the upper surface of the hydrogen-terminated diamond 4, the second gate electrode 14 is located on the second dielectric layer 13, and the second dielectric layer 13 and the second gate electrode 14 are both located between the second source electrode 11 and the second drain electrode 12; the first drain electrode 8 and the second drain electrode 12 are metal-interconnected through a first interconnect line 15, and the first gate electrode 10 and the second gate electrode 14 are metal-interconnected through a second interconnect line 16.

[0125] The hydrogen-terminated diamond 4 serves as a p-type conductive channel, the gallium nitride HEMT structure 3 serves as an n-type conductive channel, and carriers migrate in the p-type conductive channel and the n-type conductive channel.

[0126] The material of the diamond substrate 1 is homogeneous or heterogeneous diamond prepared by high temperature and high pressure HPHT technology or vapor phase epitaxy CVD technology.

[0127] The materials of the intermediate layer 2 include but are not limited to amorphous carbon, SiO2, AlN, SiN x , BN, thickness is 5 to 200 nm.

[0128] The GaN HEMT structure 3 includes but is not limited to a GaN or AlGaN buffer layer, a GaN channel layer, an AlN spacer layer, an AlGaN barrier layer, and a p-GaN cap layer; the materials of the first source electrode 7 and the first drain electrode 8 include Ti, Al, Ni, and Au from bottom to top, with thicknesses of 20nm, 150nm, 30-40nm, and 50-80nm, respectively; the material of the first dielectric layer 9 includes SiN x , SiO2, Al2O3, etc., with a thickness of 10 to 500nm; the material of the first gate electrode 10 includes Ni and Au from bottom to top, with thicknesses of 30nm and 200nm respectively.

[0129] The thickness of the hydrogen-terminated diamond 4 is 1 to 20 nm; the material of the second source electrode 11 and the second drain electrode 12 is the same, including one or more of Au, Pd, Ir, Pt, Ti, and Ni, with a thickness of 50 to 500 nm; the material of the second dielectric layer 13 includes one or more of Al2O3, TiO2, and MoO3, with a thickness of 10 to 500 nm; the material of the second gate electrode 14 includes one or more of Al, Zr, Hf, and Mo, with a thickness of 50 to 500 nm.

[0130] The method for preparing a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated complementary circuit of the present invention is carried out in sequence according to the following steps:

[0131] Providing a sample, including a diamond substrate 1, an intermediate layer 2 and a gallium nitride HEMT structure 3;

[0132] The gallium nitride HEMT structure 3 and the intermediate layer 2 on one side are removed by etching technology until the diamond substrate 1 is exposed, and at the same time, a mesa structure of the gallium nitride HEMT device is formed to achieve device isolation;

[0133] Etch or passivate the p-GaN cap layer on the surface of the GaN HEMT structure by using photolithography and etching or plasma processing technology, and only retain the p-GaN layer 17 in the gate area;

[0134] Using photolithography and deposition technology, a first source electrode 7 and a first drain electrode 8 are deposited at both ends of the gallium nitride HEMT structure 3 to form ohmic contacts, followed by annealing;

[0135] Depositing a protective layer on the GaN HEMT structure and performing a hydrogenation treatment on one side of the diamond substrate 1 to form a hydrogen-terminated diamond 4, while repairing the diamond and AlGaN lattices damaged by etching;

[0136] Performing oxygen termination treatment on the surface of one side of the diamond substrate 1 to form oxygen-terminated diamond 5 to achieve device isolation;

[0137] A second source electrode 11, a second drain electrode 12, a second dielectric layer 13 and a second gate electrode 14 are formed on the hydrogen-terminated diamond 4;

[0138] By using photolithography and deposition technology, a first gate electrode 10 is deposited on the gallium nitride HEMT, and then a first interconnection line 15 and a second interconnection line 16 are deposited on the sample to realize metal interconnection between the first drain electrode 11 and the second drain electrode 12 through the first interconnection line 15, and metal interconnection between the first gate electrode 10 and the second gate electrode 14 through the second interconnection line 16.

[0139] The connection method between the diamond substrate and the gallium nitride HEMT structure includes bonding of diamond and the gallium nitride HEMT structure, epitaxial growth of the gallium nitride HEMT structure on a single crystal diamond, or epitaxial growth of a single crystal diamond on the gallium nitride HEMT structure;

[0140] Annealing conditions: annealing atmosphere is N2, annealing temperature is 750℃~900℃, annealing time is 25s~180s.

[0141] The protective layer material is SiO2, SiN x The thickness is 100 to 500 nm. The hydrogenation treatment uses MPCVD equipment, the H2 flow rate is 50 to 1000 sccm, the treatment temperature is 500-900°C, and the treatment time is 10s to 2h.

[0142] The oxygen terminal treatment specifically includes: using ultraviolet rays or ozone or oxygen plasma to treat the diamond surface, wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 minutes.

[0143] The first drain electrode 8 and the second drain electrode 12 are metal interconnected through a first interconnection line 15, the first gate electrode 10 and the second gate electrode 14 are metal interconnected through a second interconnection line 16, the first source electrode 7 is grounded, and the second source electrode 11 is connected to a power supply voltage. Figure 7 shown.

[0144] The deposition methods described in the above steps include plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atomic layer deposition, electron beam evaporation, sputtering, etc.; the photolithography technology includes ultraviolet lithography, electron beam lithography and step-by-step non-contact lithography.

[0145] Example 3

[0146] A method for preparing a complementary circuit of a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated comprises the following steps:

[0147] 1) providing a diamond substrate, epitaxially growing an AlN intermediate layer on the diamond substrate, epitaxially growing a gallium nitride substrate on the AlN using a metal organic chemical vapor deposition technique, and growing an epitaxial structure on the surface of the gallium nitride substrate, wherein the epitaxial structure includes a GaN channel layer, an AlN spacer layer, an AlGaN barrier layer, and a p-GaN cap layer sequentially grown on the surface of the substrate;

[0148] 2) Using Al as a mask, photolithography and ICP processes are used to etch and remove the p-GaN cap layer, AlGaN barrier layer, AlN spacer layer, GaN channel layer, gallium nitride substrate and AlN intermediate layer on one side until the diamond substrate is exposed as an electronic-grade single-crystal diamond epitaxial layer substrate, and at the same time, a GaN HEMT device table is formed to achieve HEMT device isolation; the etching conditions are: the reaction gases are Cl2, BCl3 and Ar, and their flow rates are 80sccm, 10sccm and 5sccm respectively, and the RF powers of the upper electrode and the lower electrode are 1000W and 100W respectively; then the sample is placed in a hydrochloric acid solution for cleaning to completely remove the Al mask, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0149] 3) Etching the p-GaN layer outside the gate region by photolithography and ICP process to form a p-GaN layer. The etching conditions are as follows: the reaction gases are Cl2 and N2, with flow rates of 30 and 10 sccm respectively, the ICP source power is 200 W, the RF power is 60 W, the pressure is 20 mTorr, and the etching temperature is 20°C;

[0150] 4) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist in the area corresponding to the source and drain electrodes; then placing the sample in an electron beam evaporation chamber, depositing titanium, aluminum, nickel and gold in sequence, with the thickness of the four metal layers being 20nm, 150nm, 30nm and 50nm respectively; after the evaporation, placing the sample in an acetone solution for stripping, and removing the multiple layers of metal on the photoresist; then performing annealing at a temperature of 900°C for 30 seconds to form ohmic contacts of the first source electrode and the first drain electrode;

[0151] 5) A 300nm SiO2 protective layer was deposited on one side of the GaN HEMT structure as a mask to protect the sample ohmic contact and active area. The sample was placed in the MPCVD chamber, and the microwave plasma power was controlled to make the chamber temperature 700℃. The hydrogen flow rate was maintained at 500sccm. The diamond substrate was hydrogenated and the lattice of the etched diamond, p-type GaN, and AlGaN surfaces was repaired. The processing time was 20min, and a two-dimensional hole gas surface density of 2×10 13 cm-2 , the mobility is 150cm 2 / V·s hydrogen-terminated diamond, the thickness of hydrogen-terminated diamond is 1nm;

[0152] 6) Apply photoresist and spin the sample, and bake it on a 100°C hot plate for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form an active area pattern on one side of the diamond; then place the sample in an electron beam evaporator chamber to deposit 150nm of Au, and after the evaporation, place the sample in an acetone solution for stripping;

[0153] 7) Place the sample in a UV / Ozone device and perform oxygen termination treatment on the surfaces of both sides of the diamond substrate for 15 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond;

[0154] 8) Place the sample in a RIE etcher to completely remove the SiO2 protective layer on the GaN;

[0155] The sample is coated with photoresist and spun on it, and then baked on a hot plate at 100°C for 90 seconds; the sample is placed in a photolithography machine for exposure; the exposed sample is placed in a developer for 80 seconds to remove the photoresist on the Au layer; then KI / I2 solution is used for etching to form a gate window; the sample is placed in an electron beam evaporator chamber, 50 / 150nm ZrO2 / Al is deposited, and after stripping, the second source electrode and the second drain electrode are ohmic contacts, and the second dielectric layer and the second gate electrode are obtained;

[0156] 9) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100° C. for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist on the gate strip; then placing the sample in an electron beam evaporation machine chamber, depositing nickel and gold in sequence, with thicknesses of 30 nm and 200 nm respectively, and after the evaporation, placing the sample in an acetone solution for stripping, removing the multilayer metal on the photoresist, and obtaining a first gate electrode, a first interconnection line, and a second interconnection line, thereby realizing the interconnection between the first drain electrode and the second drain electrode, and the interconnection between the first gate electrode and the second gate electrode.

[0157] Example 4

[0158] A method for preparing a complementary circuit of a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated, referring to Figure 6 , including the following steps:

[0159] 1) Bonding single crystal diamond to GaN HEMT structure, GaN HEMT structure includes SiC substrate, GaN buffer layer, GaN channel layer, AlN interface layer, Al 0.25 Ga 0.75 N barrier layer and p-GaN cap layer, the main bonding steps include using photoresist to bond the surface of the GaN epitaxial layer of the GaN HEMT on the SiC substrate to the silicon wafer (temporary carrier); using mechanical grinding to thin the SiC substrate to 40μm; polishing the SiC substrate and the single crystal diamond to make the surface roughness less than 0.5nm; using the SiC substrate and the polished surface of the single crystal diamond as the surface to be bonded, and subjecting them to argon plasma treatment, with a plasma discharge power of 50W and a treatment time of 5min; then in situ depositing a 2nm thick tungsten buffer layer and a 10nm thick gold film on the surface to be bonded; Without exposure to the atmosphere, the gallium nitride HEMT and the single crystal diamond were pre-bonded by mechanical pressure, with an applied pressure of 0.3 MPa and a pressurization time of 3 min. Then, the wafer was placed in a bonding device for secondary bonding, with an applied pressure of 5 MPa and a pressurization time of 5 min. Subsequently, the wafer was placed in an acetone solution to remove the photoresist and temporary carrier on the surface of the gallium nitride on the single crystal diamond substrate, and a diamond-based gallium nitride composite wafer was obtained. Finally, the diamond-based gallium nitride composite wafer was annealed in a vacuum environment, with an annealing temperature of 150°C and an annealing time of 40 min, to complete the bonding between the single crystal diamond and the gallium nitride HEMT.

[0160] 2) Using SiO2 as a mask, photolithography and RIE etching are used to remove the gallium nitride HEMT on one side until the single crystal diamond substrate is exposed as an electronic grade single crystal diamond epitaxial layer substrate, and at the same time, the GaN HEMT device table is formed, the active area is defined, and the HEMT device isolation is realized; the etching conditions are: the reaction gases are Cl2, BCl3 and He, and their flow rates are 50sccm, 8sccm and 150sccm respectively, the reaction chamber pressure is 1500 mTorr, and the forward power is 200W; then the sample is placed in BOE solution (Buffered Oxide Etch) for cleaning to completely remove the SiO2 mask, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0161] 3) The p-GaN layer in the source and drain deposition area was etched using photolithography and ICP processes. The etching conditions were as follows: the reaction gases were Cl2 and N2, with flow rates of 30 and 10 sccm, respectively, the ICP source power was 200 W, the RF power was 60 W, the pressure was 20 mTorr, and the etching temperature was 20 ° C. The sample was placed in acetone for cleaning to completely remove the photoresist, and then the sample was rinsed with ultrapure water and dried with nitrogen;

[0162] 4) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist in the area corresponding to the source and drain electrodes; then placing the sample in an electron beam evaporation chamber, depositing titanium, aluminum, nickel and gold in sequence, with the thickness of the four metal layers being 17.5nm, 175nm, 40nm and 80nm respectively; after the evaporation, placing the sample in an acetone solution for stripping, and removing the multiple layers of metal on the photoresist; then performing an annealing treatment, with the annealing temperature being 850°C and the annealing time being 45s, to form an ohmic contact between the first source electrode and the first drain electrode;

[0163] 5) A 400nm SiO2 protective layer was deposited on one side of the GaN HEMT structure as a mask to protect the sample ohmic contact and active area, and to leak out part of the p-GaN area between the gate source and the gate drain. The sample was placed in an MPCVD chamber, and the microwave plasma power was controlled to make the chamber temperature 600°C. The hydrogen flow rate was maintained at 100sccm, and the exposed diamond was hydrogenated. At the same time, the lattice of the etched diamond and aluminum gallium nitride surface was repaired, and the p-GaN cap layer outside the gate area was passivated to make it a high-resistance state. The processing time was 30min, and a two-dimensional hole gas surface density of 1×10 13 cm -2 , the mobility is 180cm 2 / V·s hydrogen-terminated diamond, the thickness of hydrogen-terminated diamond is 20nm;

[0164] 6) Apply and spin photoresist on the sample, and bake it on a hot plate at 100°C for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form a source-drain electrode pattern on one side of the diamond; then place the sample in an electron beam evaporation chamber to deposit 100nm of Au, and after the evaporation, place the sample in an acetone solution for stripping to obtain a second source electrode and a second drain electrode ohmic contact;

[0165] 7) Apply and spin photoresist on the sample, and bake it on a 100°C hot plate for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form an isolation pattern; place the sample in a UV / Ozone device and treat the sample for 20 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond; then use an acetone solution to remove the photoresist on the sample surface;

[0166] 8) Place the sample in a RIE etcher to completely remove the SiO2 protective layer on the GaN;

[0167] The sample was coated with photoresist and spun, and then placed on a 100°C hot plate for baking for 90 seconds; the sample was placed in a photolithography machine for exposure; the exposed sample was placed in a developer for 80 seconds to form a gate dielectric layer pattern; the sample was placed in an electron beam evaporator chamber, 50 / 150nm HfO2 / Al was deposited, and the second dielectric layer and the second gate electrode were obtained after peeling;

[0168] 9) Apply and spin photoresist on the sample, and bake it on a hot plate at 100°C for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form a gate pattern; then place the sample in an electron beam evaporator chamber, and deposit nickel and gold on the p-GaN layer in turn with thicknesses of 20nm and 150nm, respectively. After the evaporation, place the sample in an acetone solution for stripping, remove the multi-layer metal on the photoresist, and obtain a first gate electrode, a first interconnection line and a second interconnection line, thereby realizing the interconnection between the first drain electrode and the second drain electrode, and the interconnection between the first gate electrode and the second gate electrode.

[0169] Example 5

[0170] A method for preparing a complementary circuit of a hydrogen-terminated diamond MOSFET / p-GaN gate structure gallium nitride HEMT monolithically integrated comprises the following steps:

[0171] 1) Bonding single crystal diamond to GaN HEMT structure, GaN HEMT structure includes SiC substrate, GaN buffer layer, GaN channel layer, AlN interface layer, Al 0.25 Ga 0.75 N barrier layer and p-GaN cap layer. The main bonding steps include bonding the surface of the GaN epitaxial layer of the GaN HEMT on the SiC substrate to the silicon wafer (temporary carrier) with photoresist; thinning the SiC substrate to 20 μm by mechanical grinding; polishing the SiC substrate and the single crystal diamond to a surface roughness of less than 0.2 nm; treating the SiC substrate and the polished surface of the single crystal diamond as the bonding surface with argon plasma, with a plasma discharge power of 50 W and a treatment time of 1 0min; then, the GaN HEMT and the single crystal diamond were pre-bonded by mechanical pressure in situ, with an applied pressure of 5MPa and a pressurization time of 8min; then, the photoresist and temporary carrier on the surface of the GaN single crystal diamond substrate were removed in an acetone solution to obtain a diamond-based GaN composite wafer; finally, the diamond-based GaN composite wafer was annealed in a vacuum environment at a temperature of 200°C and an annealing time of 60min to complete the bonding of the single crystal diamond and the GaN HEMT;

[0172] 2) Using SiO2 as a mask, photolithography and ICP etching are used to remove the gallium nitride HEMT on one side until the single crystal diamond substrate is exposed as an electronic grade single crystal diamond epitaxial layer substrate, and at the same time, the GaN HEMT device table is formed, the active area is defined, and the HEMT device isolation is realized; the etching conditions are: the reaction gases are Cl2, BCl3 and Ar, and their flow rates are 50, 8 and 5 sccm respectively, the reaction chamber pressure is 1500mTorr, the ICP power is 1000W, and the forward power is 200W; then the sample is placed in a BOE solution for cleaning to completely remove the SiO2 mask, and then the sample is rinsed with ultrapure water and blown dry with nitrogen;

[0173] 3) The p-GaN layer in the source and drain deposition area was etched using photolithography and ICP processes. The etching conditions were as follows: the reaction gases were Cl2 and N2, with flow rates of 25 and 8 sccm, respectively, the ICP source power was 200 W, the RF power was 60 W, the pressure was 20 mTorr, and the etching temperature was 20°C. After etching, the sample was placed in acetone for cleaning to completely remove the photoresist, and then the sample was rinsed with ultrapure water and dried with nitrogen;

[0174] 4) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100°C for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist in the area corresponding to the source and drain electrodes; then placing the sample in an electron beam evaporation chamber, sequentially depositing four metals of titanium, aluminum, nickel and gold, with the thickness of the four metal layers being 20nm, 160nm, 50nm and 100nm respectively; after the evaporation, placing the sample in an acetone solution for stripping, and removing the multiple layers of metal on the photoresist; then performing annealing at a temperature of 870°C for 30 seconds to form ohmic contacts of the first source electrode and the first drain electrode;

[0175] 5) A 300nm SiO2 protective layer was deposited on one side of the GaN HEMT structure as a mask to protect the sample ohmic contact and active area, and to expose the p-GaN layer outside the p-GaN gate area. The sample was placed in an MPCVD chamber, and the microwave plasma power was controlled to make the chamber temperature 650°C. The hydrogen flow rate was maintained at 300sccm, and the diamond substrate was hydrogenated. At the same time, the lattice of the etched diamond and aluminum gallium nitride surfaces was repaired, and the p-GaN cap layer outside the gate area was passivated to make it a high-resistance state. The processing time was 30min, and a two-dimensional hole gas surface density of 1×10 13 cm -2 , the mobility is 180cm 2 / V·s hydrogen-terminated diamond, the thickness of hydrogen-terminated diamond is 10nm;

[0176] 6) Apply photoresist and spin the sample, and bake it on a 100°C hot plate for 90 seconds; place the sample in a photolithography machine for exposure; place the exposed sample in a developer for 80 seconds to form an active area pattern on one side of the diamond; then place the sample in an electron beam evaporator chamber to deposit 150nm of Au, and after the evaporation, place the sample in an acetone solution for stripping;

[0177] 7) Place the sample in a UV / Ozone device and treat the sample for 20 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond;

[0178] 8) Place the sample in a RIE etcher to completely remove the SiO2 protective layer on the GaN;

[0179] The sample is coated with photoresist and spun on it, and then baked on a hot plate at 100°C for 90 seconds; the sample is placed in a photolithography machine for exposure; the exposed sample is placed in a developer for 80 seconds to remove the photoresist on the Au layer; then KI / I2 solution is used for etching to form a gate window; the sample is placed in an electron beam evaporator chamber, and 20 / 300nm LaB6 / Al is deposited, and after stripping, the second source electrode and the second drain electrode are ohmic contacts, and the second dielectric layer and the second gate electrode are obtained;

[0180] 9) Applying and spinning photoresist on the sample, and baking it on a hot plate at 100° C. for 90 seconds; placing the sample in a photolithography machine for exposure; placing the exposed sample in a developer for 80 seconds to remove the photoresist on the gate strip; then placing the sample in an electron beam evaporation machine chamber, depositing nickel and gold in sequence, with thicknesses of 30 nm and 200 nm respectively, and after the evaporation, placing the sample in an acetone solution for stripping, removing the multilayer metal on the photoresist, and obtaining a first gate electrode, a first interconnection line, and a second interconnection line, thereby realizing the interconnection between the first drain electrode and the second drain electrode, and the interconnection between the first gate electrode and the second gate electrode.

[0181] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, they are also intended to be included.

Claims

1. A hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit, characterized in that: It comprises a diamond substrate (1), an intermediate layer (2) is arranged on one side of the surface of the diamond substrate (1), and an enhanced gallium nitride HEMT structure is arranged on the intermediate layer (2); A hydrogen-terminated diamond (4) is arranged on the other side of the surface of the diamond substrate (1); oxygen-terminated diamonds (5) are arranged on the diamond substrate (1) and at both ends of the hydrogen-terminated diamond (4); a second source electrode (11) is arranged on one side of the surface of the hydrogen-terminated diamond (4), and a second drain electrode (12) is arranged on the other side; a second dielectric layer (13) is arranged on the surface of the hydrogen-terminated diamond (4); a second gate electrode (14) is arranged on the second dielectric layer (13); and the second dielectric layer (13) and the second gate electrode (14) are both located between the second source electrode (11) and the second drain electrode (12); The hydrogen-terminated diamond (4) serves as a p-type conductive channel, the gallium nitride HEMT structure serves as an n-type conductive channel, and carriers migrate in the p-type conductive channel and the n-type conductive channel.

2. The hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit according to claim 1, characterized in that: The enhanced-mode gallium nitride HEMT structure is a recessed gate gallium nitride HEMT structure, comprising a gallium nitride HEMT structure (3), a passivation layer (6), a first dielectric layer (9), a first source electrode (7), a first drain electrode (8) and a first gate electrode (10), the gallium nitride HEMT structure (3) being located on the intermediate layer (2), a gate recess being provided on the surface of the gallium nitride HEMT structure (3), the passivation layer (6) being provided on the surface of the gallium nitride HEMT structure (3) and being located outside the gate recess, and the first dielectric layer (9) being provided on the surface of the passivation layer (6) and the gate recess. ), the first gate electrode (10) is located in a gate groove region on the first dielectric layer (9); a first source electrode (7) is arranged on one side of the surface of the gallium nitride HEMT structure (3), and a first drain electrode (8) is arranged on the other side, and the first gate electrode (10), the first dielectric layer (9), and the passivation layer (6) are all located between the first source electrode (7) and the first drain electrode (8); the first drain electrode (8) and the second drain electrode (12) are metal interconnected through a first interconnection line (15), and the first gate electrode (10) and the second gate electrode (14) are metal interconnected through a second interconnection line (16).

3. The hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit according to claim 1, characterized in that: The enhanced-mode gallium nitride HEMT structure is a p-GaN gate structure gallium nitride HEMT structure, the p-GaN gate structure gallium nitride HEMT structure comprising a gallium nitride HEMT structure (3), the surface layer of the gallium nitride HEMT structure (3) being configured as a p-GaN cap layer, the p-GaN cap layer on the surface layer of the gallium nitride HEMT structure (3) except for a gate region is etched or passivated, and a p-GaN layer (17) is formed in the gate region, a first gate electrode (10) is arranged on the p-GaN layer (17), a first source electrode (7) and a first drain electrode (8) are respectively arranged on both sides of the etched or passivated region of the gallium nitride HEMT structure (3), the first gate electrode (10) is located between the first source electrode (7) and the first drain electrode (8); the first drain electrode (8) and the second drain electrode (12) are metal interconnected through a first interconnection line (15), and the first gate electrode (10) and the second gate electrode (14) are metal interconnected through a second interconnection line (16).

4. The hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit according to claim 2, characterized in that: The diamond substrate (1) is homogeneous or heterogeneous diamond; The two-dimensional vacancy density of the hydrogen-terminated diamond (4) is 1×10 12 ~5×10 14 cm -2 , the mobility is 20~2500cm 2 / (V·s), the thickness of the hydrogen-terminated diamond (4) is 1 nm to 20 nm.

5. The method for preparing a hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit according to claim 2, characterized in that: The following steps are involved: Step 1, providing a sample, including a diamond substrate (1), an intermediate layer (2) and a gallium nitride HEMT structure (3); Step 2, using an etching technique to remove the gallium nitride HEMT structure (3) and the intermediate layer (2) on one side of the diamond substrate (1) until the diamond substrate (1) is exposed, and at the same time, a mesa structure of the gallium nitride HEMT device is formed to achieve device isolation; Step 3, depositing a passivation layer (6) on the surface of the sample; Step 4, using photolithography and etching technology, remove the passivation layer (6) in the source and drain electrode regions of the gallium nitride HEMT structure (3) to expose the source and drain electrode regions, and simultaneously remove the passivation layer (6) on the other side of the diamond substrate (1); Step 5, using photolithography and deposition technology, depositing a first source electrode (7) and a first drain electrode (8) ohmic contacts in the source and drain electrode regions of the gallium nitride HEMT structure (3), respectively, and then performing annealing; Step 6, using photolithography and etching technology, etching the passivation layer (6) under the gate region and a portion of the AlGaN barrier layer of the gallium nitride HEMT structure (3) to form a gate groove; Step 7, depositing a protective layer on the surface of the gallium nitride HEMT structure, and performing a hydrogenation treatment on the other side of the diamond substrate (1) to form hydrogen-terminated diamond (4), while repairing the diamond and aluminum gallium nitride lattices damaged by etching; Step 8, using photolithography and deposition technology, depositing a second source electrode (11) and a second drain electrode (12) ohmic contact at both ends of the hydrogen terminal diamond (4); Step 9, performing oxygen termination treatment on the surfaces of both sides of the diamond substrate to form oxygen-terminated diamond (5) to achieve device isolation; Step 10, removing the protective layer on the surface of the gallium nitride HEMT structure (3), depositing a first dielectric layer (9) on the passivation layer (6) and the surface of the gate groove by using photolithography and deposition technology, and depositing a second dielectric layer (13) on the hydrogen-terminated diamond (4); Step 11, depositing a first gate electrode (10) in the gate groove region by using photolithography and deposition technology; Step 12, depositing a second gate electrode (14) in the middle region between the second source electrode (11) and the second drain electrode (12) on the second dielectric layer (13), and depositing a first interconnection line (15) and a second interconnection line (16) on the sample at the same time, so that the first drain electrode (8) and the second drain electrode (12) are metal interconnected through the first interconnection line (15), and the first gate electrode (10) and the second gate electrode (14) are metal interconnected through the second interconnection line (16).

6. The preparation method according to claim 5, characterized in that: In step 1, the connection method between the diamond substrate (1) and the gallium nitride HEMT structure (3) includes bonding diamond to the gallium nitride HEMT structure, epitaxially growing the gallium nitride HEMT structure on single crystal diamond, or epitaxially growing single crystal diamond on the gallium nitride HEMT structure.

7. The preparation method according to claim 5, characterized in that: The etching technology in step 2, step 4 and step 6 is to use inductively coupled plasma etching, with a plasma power of 50 to 1000 W and a rate of 1 to 1000 nm / min; In step 5, the annealing conditions are: annealing atmosphere is N2, annealing temperature is 750-900°C, and annealing time is 25s-180s; The protective layer material in step 7 is SiO2 or SiN x , thickness is 100~500nm; hydrogenation treatment uses MPCVD equipment, H2 flow rate is 50~1000sccm, treatment temperature is 500~900℃, and treatment time is 10s to 2h; In step 9, the oxygen terminal treatment is specifically to use ultraviolet rays, ozone or oxygen plasma to treat the surface of the diamond substrate (1), wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 min.

8. The method for preparing a hydrogen-terminated diamond MOSFET / enhancement-mode gallium nitride HEMT monolithically integrated complementary circuit according to claim 3, characterized in that: The following steps are involved: Providing a sample, comprising a diamond substrate (1), an intermediate layer (2) and a gallium nitride HEMT structure (3); Using etching technology to remove the gallium nitride HEMT structure (3) and the intermediate layer (2) on one side of the diamond substrate (1) until the diamond substrate (1) is exposed, and at the same time forming a mesa structure of the gallium nitride HEMT device to achieve device isolation; Using photolithography and etching or plasma processing technology, etching or passivating the p-GaN cap layer on the surface of the GaN HEMT structure (3) to only retain the p-GaN layer (17) in the gate region; Using photolithography and deposition technology, depositing a first source electrode (7) and a first drain electrode (8) ohmic contacts at both ends of the gallium nitride HEMT structure (3) processed in step 3, and then performing annealing; Depositing a protective layer on the treated gallium nitride HEMT structure (3), and performing a hydrogenation treatment on one side of the diamond substrate (1) to form hydrogen-terminated diamond (4), while repairing the diamond and aluminum gallium nitride lattices damaged by etching; Performing oxygen termination treatment on the surfaces of both sides of the diamond substrate (1) to form oxygen-terminated diamond (5) to achieve device isolation; forming a second source electrode (11), a second drain electrode (12), a second dielectric layer (13) and a second gate electrode (14) on the hydrogen-terminated diamond (4); By using photolithography and deposition technology, a first gate electrode (10) is deposited on a p-GaN layer (17), and then a first interconnection line (15) and a second interconnection line (16) are deposited on the sample, so that a first drain electrode (8) and a second drain electrode (12) are metal-interconnected through the first interconnection line (15), and a first gate electrode (10) and a second gate electrode (14) are metal-interconnected through the second interconnection line (16).

9. The preparation method according to claim 8, characterized in that: The connection method between the diamond substrate (1) and the gallium nitride HEMT structure (3) includes bonding of diamond and the gallium nitride HEMT structure, epitaxy of the gallium nitride HEMT structure on a single crystal diamond, or epitaxy of a single crystal diamond on the gallium nitride HEMT structure; Annealing conditions: annealing atmosphere is N2, annealing temperature is 750-900°C, annealing time is 25-180s; The protective layer material is SiO2 or SiN x , thickness is 100~500nm, hydrogenation treatment uses MPCVD equipment, H2 flow rate is 50~1000sccm, treatment temperature is 500~900℃, and treatment time is 10s to 2h; The oxygen terminal treatment specifically includes: using ultraviolet rays, ozone or oxygen plasma to treat the surface of the diamond substrate (1), wherein the gas flow rate of oxygen or ozone is 1 to 100 sccm, the plasma power is 30 to 300 W, and the treatment time is 1 to 60 minutes.

10. The preparation method according to claim 5 or 8, characterized in that: Deposition methods include plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atomic layer deposition, electron beam evaporation or sputtering; lithography technology includes ultraviolet lithography, electron beam lithography or step-and-step non-contact lithography.

Images