A diamond field effect transistor and a method of manufacturing the same

Abstract

The application discloses a diamond field effect transistor and a preparation method thereof, and the diamond field effect transistor comprises a diamond substrate, a single-crystal diamond epitaxial film, a source electrode, a drain electrode, a stress regulation film and a gate electrode; the single-crystal diamond epitaxial film is arranged on the diamond substrate; the single-crystal diamond epitaxial film is provided with a hydrogen terminal region and an oxygen terminal region, the hydrogen terminal region is a channel region composed of a two-dimensional hole gas conductive layer; the source electrode and the drain electrode are arranged at two ends of the channel region respectively; the stress regulation film is arranged on the source electrode, the drain electrode and the channel region without the source electrode and the drain electrode; and the gate electrode is arranged on the stress regulation film and the oxygen terminal region. The stress regulation film is introduced in the application; based on the stress regulation film, the carrier mobility can be enhanced through stress regulation, and the performance of the conductive channel is not damaged.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor device technology, and specifically relates to a diamond field-effect transistor and its fabrication method. Background Technology

[0002] With the application of first-generation semiconductor materials silicon (Si) and germanium (Ge) in electronic devices, human technological life entered a fast track. Driven by technological progress and the development needs of integrated circuits, second-generation semiconductor materials gallium arsenide (GaAs) and third-generation semiconductor materials silicon carbide (SiC) and gallium nitride (GaN) were also developed and utilized. Moore's Law requires the integration of more electronic devices in a unit area, which has led to increasingly prominent problems such as heat dissipation, gate breakdown, and tunneling leakage current. In order to solve the above problems, people have gradually turned their attention to emerging semiconductor materials.

[0003] Compared with other semiconductor materials, diamond exhibits a wide bandgap, high mobility, high thermal conductivity, and large Johnson, Baliga, and Keyes quality factors. As shown in Table 1, which compares the quality factors of diamond with those of Si, GaN, and SiC, its electrical properties are significantly superior to those of the other three generations of semiconductor materials, resulting in diamond-based electronic devices that outperform other semiconductor electronic devices. Furthermore, it covers a wide range of applications in terms of output power and operating frequency, making it highly suitable for fabricating ultra-high frequency, ultra-high power, high-temperature resistant, and radiation-resistant electronic devices. Therefore, it has enormous application potential in aerospace and advanced equipment fields where requirements for material size, weight, heat dissipation, power density, and reliability are extremely high.

[0004] Table 1. Comparison of diamond material quality factors with those of Si, GaN, and SiC

[0005] Material Johnson Index Keyes Index Baliga index [Si=1] diamond 2530 145 43938 SiC 910 35 620 GaN 756 104 870 Si 1 1 1

[0006] Experiments have shown that electrons in the valence band of hydrogen-terminated diamond are transferred to the lowest unoccupied molecular orbital (LOMO) of the adsorbed molecule, resulting in the formation of a two-dimensional vacancy gas (2DHG) layer on the diamond surface, which can yield 10 13 cm -2 The surface carrier concentration around 20-680 cm⁻¹ 2 ·V -1 ·s -1 Within the specified range, theoretical predictions suggest that after addressing interfacial ionized impurity scattering and roughness scattering, the carrier mobility can exceed 3000 cm⁻¹. 2 ·V -1 ·s -1 .

[0007] Before the challenges of traditional elemental doping were resolved, the aforementioned two-dimensional hole gas could be used as a conductive channel in field-effect transistors, greatly advancing the development of diamond FETs. However, due to the limitation of surface terminal bond length, hydrogen-terminated diamond has a small transfer doping dipole moment, increasing channel carrier transport and scattering, resulting in typically low mobility. In recent years, methods such as epitaxial high-quality diamond layers, amorphous carbon adsorption, and the introduction of high-dielectric-constant materials to enhance dielectric shielding have been reported to enhance the carrier mobility of conductive channels on the surface of hydrogen-terminated diamond, but the actual enhancement effect is limited. Passivating the surface of hydrogen-terminated diamond with two-dimensional materials, such as h-BN, can also improve channel carrier mobility. This is mainly because two-dimensional materials can passivate the surface states of hydrogen-terminated diamond, and some charges can be transferred on the outer surface of the two-dimensional material, increasing the charge interaction distance and reducing surface scattering, thereby significantly improving carrier mobility. However, two-dimensional materials based on exfoliation techniques cannot achieve large-size conductive channels, which is difficult to meet the requirements of practical applications. It is necessary to explore other methods to improve mobility or new device structures. Summary of the Invention

[0008] The purpose of this invention is to provide a diamond field-effect transistor and its fabrication method, thereby solving one or more of the aforementioned technical problems. The diamond field-effect transistor provided by this invention incorporates a stress-modulated thin film; based on this stress-modulated thin film, carrier mobility can be enhanced through stress modulation without damaging the performance of the conductive channel.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] The present invention provides a diamond field-effect transistor, comprising: a diamond substrate, a single-crystal diamond epitaxial thin film, a source electrode, a drain electrode, a stress-tuning thin film, and a gate electrode;

[0011] The single-crystal diamond epitaxial film is disposed on the diamond substrate; the single-crystal diamond epitaxial film is provided with a hydrogen-terminated region and an oxygen-terminated region, wherein the hydrogen-terminated region is a channel region composed of a two-dimensional hole gas conductive layer.

[0012] The source electrode and the drain electrode are respectively provided at both ends of the channel region;

[0013] The stress-regulating film is disposed on the source electrode, the drain electrode, and the channel region without source and drain electrodes. The stress-regulating film is used to regulate the stress of the single crystal diamond epitaxial film below it and the channel region to improve the carrier mobility of the two-dimensional hole gas conductive layer.

[0014] The gate electrode is disposed on the stress-modulated thin film and the oxygen-terminated region.

[0015] A further improvement of the present invention is that the material of the stress-regulating thin film is SiN. x Materials containing SiO2, Al2O3, HfO2, ZrO2, diamond-like carbon, or a work function greater than or equal to 5 eV.

[0016] A further improvement of the present invention is that the thickness of the stress-regulating film is 1 nm to 5000 nm.

[0017] A further improvement of the present invention is that the internal compressive stress of the stress-regulating film is 1 MPa to 10 GPa.

[0018] A further improvement of the present invention is that the compressive stress within the single-crystal diamond epitaxial film beneath the stress-controlled film is 10 MPa to 5 GPa.

[0019] A further improvement of the present invention is that the width of the channel region is 5 nm to 100 μm, and the carrier concentration in the channel is 1 × 10⁻⁶. 12 cm -2 ~5×10 14 cm -2 The migration rate is 20cm. 2 / V·s~2500cm 2 / V·s.

[0020] A further improvement of the present invention is that the source electrode and the drain electrode are both made of Au, Pd, Ir, Pt or Ti; and the gate electrode is made of Al, Zr, Hf or Mo.

[0021] The present invention provides a method for fabricating a diamond field-effect transistor, comprising the following steps:

[0022] Homogeneous epitaxial single-crystal diamond films are formed on cleaned diamond substrates to obtain single-crystal diamond epitaxial films.

[0023] The single-crystal diamond epitaxial film is hydrogenated to obtain a two-dimensional hole gas conductive layer;

[0024] Source electrode and drain electrode patterns are fabricated on the two-dimensional hole gas conductive layer, and source electrode metal and drain electrode metal are deposited accordingly. Ohmic contact between the source electrode and drain electrode is obtained by stripping technology.

[0025] Photoresist is applied to the source electrode, drain electrode, and the channel region between them. Oxygen termination is then performed using photolithography to form an oxygen termination region to achieve electrical isolation of the device.

[0026] A stress-controlled thin film is deposited on the source electrode, the drain electrode, and the channel region between them; the internal compressive stress of the stress-controlled thin film is adjusted to meet the preset requirements;

[0027] A gate electrode pattern is fabricated on the stress-controlled thin film and oxygen-terminated region. After depositing the gate electrode metal, the gate electrode is obtained using a lift-off technique.

[0028] A further improvement of the present invention is that, in the step of depositing the stress-modulated thin film on the source electrode, the drain electrode, and the channel region between them,

[0029] The deposition methods include electron beam evaporation, sputtering, atomic layer deposition, plasma-enhanced chemical vapor deposition, or low-pressure chemical vapor deposition.

[0030] A further improvement of the present invention is that, in the step of adjusting the magnitude of the internal compressive stress of the stress-regulating film to meet the preset requirements,

[0031] The control methods include ion implantation, thermal annealing, multilayer deposition, or ultraviolet-assisted heat treatment processes.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] This invention provides a stress-modulated diamond field-effect transistor (DFET) with enhanced carrier mobility. It introduces a stress-modulated thin film, utilizing high film stress to generate equivalent stress in the single-crystal diamond epitaxial film and the channel region. This reduces the effective mass of carriers, weakens inter-band scattering of carriers, and simultaneously reduces ionized impurity scattering at the stress-modulated film / hydrogen-terminated diamond interface. Consequently, the carrier mobility within the channel increases, improving the speed, current capacity in the on-state, and on-off ratio of the diamond-based device. Furthermore, this invention does not damage the performance of the conductive channel, and the deposited stress-modulated thin film can serve as a gate dielectric layer to reduce gate leakage current.

[0034] The preparation method provided by this invention can improve the channel carrier mobility and enhance the current transport capability between the source and drain without damaging the carrier concentration of the two-dimensional hole gas generated by the hydrogen terminal. The process steps disclosed in this invention are simple, compatible, reliable and stable, and have obvious effects on the structure of thin-film stress-controlled diamond-based field-effect transistors. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below; obviously, the drawings described below are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0036] Figure 1This is a schematic cross-sectional structure diagram of a diamond field-effect transistor with stress-modulated enhanced carrier mobility provided in an embodiment of the present invention;

[0037] Figure 2 This is a top view schematic diagram of the diamond field-effect transistor in an embodiment of the present invention;

[0038] Figure 3 This is a schematic flowchart of a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility provided in an embodiment of the present invention.

[0039] In the figure, 1 is the diamond substrate; 2 is the single-crystal diamond epitaxial film; 3 is the source electrode; 4 is the drain electrode; 5 is the channel region; 6 is the stress-tuned film; 7 is the gate electrode; and 8 is the oxygen termination region. Detailed Implementation

[0040] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] The present invention will now be described in further detail with reference to the accompanying drawings:

[0043] Please see Figure 1 and Figure 2This invention provides a diamond field-effect transistor (DFET), specifically a stress-modulated DFET with enhanced carrier mobility, comprising: a diamond substrate 1, a single-crystal diamond epitaxial film 2, a source electrode 3, a drain electrode 4, a channel region 5, a stress-modulated film 6, a gate electrode 7, and an oxygen-terminated region 8; wherein, a single-crystal diamond epitaxial film 2 is disposed on the diamond substrate 1; a channel region 5 is disposed on the single-crystal diamond epitaxial film 2; a source electrode 3 and a drain electrode 4 are disposed on the channel region 5; the channel region 5 is a hydrogen-terminated region; a stress-modulated film 6 is disposed on the source electrode 3, the drain electrode 4, and the channel region 5; and the gate electrode 7 is disposed on the stress-modulated film 6. Specifically, the channel region 5 is a hydrogen-terminated region, and the channel region 5 includes a two-dimensional hole gas conductive layer, allowing carriers to migrate within the channel.

[0044] In a specific exemplary embodiment of the present invention, the diamond substrate 1 is prepared by high temperature and high pressure HPHT technology, large area splicing technology, and vapor phase epitaxy (CVD) technology, and serves as the substrate; a single crystal diamond epitaxial film 2 is obtained by homoepitaxial growth on the substrate.

[0045] In this embodiment of the invention, the thickness of the stress-regulating thin film 6 is 1 nm to 5000 nm, and the stress film material is a dielectric material, including but not limited to SiN. x Materials include SiO2, Al2O3, HfO2, ZrO2, diamond-like carbon, and high work function materials (work function greater than or equal to 5 eV); the internal compressive stress of the thin film ranges from 1 MPa to 10 GPa. For illustrative purposes, stress-controlled thin films 6 can be deposited using methods such as electron beam evaporation, sputtering, atomic layer deposition (ALD), plasma-enhanced chemical vapor deposition (PECVD), and low-pressure chemical vapor deposition (LPCVD), with thicknesses ranging from 1 nm to 5000 nm, including but not limited to SiN. x SiO2, Al2O3, HfO2, ZrO2, and high work function materials were used. Then, stress-controlled thin films 6 were treated using ion implantation, thermal annealing, multilayer deposition, and ultraviolet-assisted heat treatment. Finally, high pressure stress was formed in the thin film, with a compressive stress of 1 MPa to 10 GPa.

[0046] In a specific exemplary embodiment of the present invention, the single-crystal diamond epitaxial film 2 is a CVD-grown diamond material, in which compressive stress is generated, with a stress magnitude of 10 MPa to 5 GPa, a resistivity greater than 100 MΩ·cm, a root mean square surface roughness of less than 0.5 nm, and a Raman curve half-width of less than 2 cm. -1The XRD rocking curve has a full width at half maximum (FWHM) of less than 30 arcsec. Hydrogenation treatment on its surface generates a two-dimensional hole gas layer, which is used as the conductive channel for a field-effect transistor. Channel region 5 is where the transistor conductive channel is located, containing the aforementioned two-dimensional hole gas conductive layer, within which charge carriers and holes can migrate. The width of channel region 5 is 5 nm to 100 μm, and the carrier concentration within the channel is 1 × 10⁻⁶. 12 cm -2 ~5×10 14 cm -2 The migration rate is 20cm. 2 / V·s~2500cm 2 / V·s.

[0047] In specific illustrative terms of this embodiment, the coverage area of ​​the stress-controlled thin film 6 includes, but is not limited to, the source electrode 3, the drain electrode 4, and the channel region 5; the source electrode 3 and the drain electrode 4 are made of materials such as Au, Pd, Ir, Pt, or Ti, and form good ohmic contact with the hydrogen-terminated diamond; the gate electrode 7 is made of metals such as Al, Zr, Hf, or Mo.

[0048] Please see Figure 3 The invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, which specifically includes the following steps:

[0049] Step 1: Clean the diamond substrate 1 and dry it;

[0050] Step 2: Homogeneously epitaxial single-crystal diamond film is formed on diamond substrate 1 to obtain single-crystal diamond epitaxial film 2;

[0051] Step 3: Hydrogenation treatment is performed on the single crystal diamond epitaxial film 2 to obtain a two-dimensional hole gas conductive layer, namely the channel region 5.

[0052] Step 4: Clean the hydrogenated single-crystal diamond epitaxial film 2, then use photolithography to form source and drain electrode patterns on its surface, deposit source and drain electrode metals, and use lift-off technology to obtain ohmic contact between source electrode 3 and drain electrode 4.

[0053] Step 5: Using photolithography, photoresist is applied to the source and drain electrodes and the hydrogen-terminated diamond between them to perform oxygen termination treatment, transforming the exposed hydrogen-terminated diamond into oxygen-terminated diamond, forming the oxygen termination region 8, thereby achieving electrical isolation of the device.

[0054] Step 6: Deposit stress-controlled thin film 6 on source electrode 3, drain electrode 4 and hydrogen terminal channel region 5 using deposition methods such as electron beam evaporation, sputtering, atomic layer deposition (ALD), plasma enhanced chemical vapor deposition (PECVD), and low pressure chemical vapor deposition (LPCVD).

[0055] Step 7: The stress-modulated thin film 6 is treated using ion implantation, thermal annealing, multilayer deposition technology and ultraviolet-assisted heat treatment to control the stress magnitude;

[0056] Step 8: Use photolithography to form a gate electrode pattern on the channel region 5, deposit gate electrode metal, and use lift-off technology to obtain the gate electrode 7.

[0057] The single-crystal diamond epitaxial film 2 obtained in step 2 of this embodiment is a CVD-grown diamond material with compressive stress generated within it, the stress magnitude being 10 MPa to 5 GPa, resistivity greater than 100 MΩ·cm, root mean square surface roughness less than 0.5 nm, and Raman curve half-width less than 2 cm. -1 The half-width of the XRD rocking curve is less than 30 arcsec.

[0058] In step 3 of this embodiment, the hydrogenation treatment involves placing the diamond sample in a hydrogen plasma or hydrogen atmosphere at a temperature of 700℃ to 1000℃ for a duration of 10 seconds to 2 hours. The width of the formed hydrogen terminal channel region 5 is 5 nm to 100 μm, and the carrier concentration within the channel is 1 × 10⁻⁶. 12 cm -2 ~5×10 14 cm -2 The migration rate is 20cm. 2 / V·s~2500cm 2 / V·s.

[0059] In step 5 of this embodiment of the invention, the oxygen terminal treatment electrical isolation specifically includes: treating the surface of the single-crystal diamond epitaxial film 2 with ultraviolet light and / or ozone, oxygen plasma, wherein the gas flow rate of oxygen or ozone is 1 sccm to 100 sccm, the plasma power is 100W to 300W, and the treatment time is 1 min to 60 min.

[0060] In step 6 of this embodiment, the deposition temperature of PECVD is 200℃~370℃, the SiH4 to NH3 gas flow rate ratio is 2~4, the reaction pressure is 400mTorr~500mTorr, and the power source frequency is 20W~500W; the deposition temperature of LPCVD is 600℃~1000℃, the SiH2Cl2 to NH3 gas flow rate ratio is 5~10, the reaction pressure is 100mTorr~300mTorr, and the power source frequency is 20W~500W; the deposition temperature of ALD is 100℃~400℃, and the background vacuum is 2~10×10 -5 Pa, carrier gas flow rate 100 sccm~400 sccm; electron beam evaporation heating temperature 20℃~1000℃, background vacuum 2~10×10 -5 Pa, electric field strength of 5kV~10kV, electron gun power of 1kW~5kW; substrate heating temperature of sputtering of 20℃~1000℃, background vacuum of 2~10×10 -5 Pa, substrate bias voltage is 0V to -500V, power supply power is 50W to 2000W.

[0061] In step 7 of this embodiment of the invention, the ion implanted by the ion implantation technique is P. + As + Sb + BF2 + The process can regulate film stress; the annealing temperature of the annealing process is 100℃~1200℃, and the annealing time is 5s~2h; the treatment temperature of the ultraviolet-assisted heat treatment is 100℃~500℃, the treatment time is 5s~30min, and the magnitude of the internal compressive stress of the film is 1MPa~10GPa.

[0062] The photolithography techniques in steps 4 and 8 of this embodiment include ultraviolet lithography, electron beam lithography, and step-by-step non-contact lithography.

[0063] In summary, the stress-modulated diamond field-effect transistor with enhanced carrier mobility provided in this embodiment of the invention includes a diamond substrate, a single-crystal diamond epitaxial film, a source electrode, a drain electrode, a channel region (hydrogen terminal), a stress-modulated film, a gate electrode, and an oxygen terminal region. Specifically, a single-crystal diamond epitaxial film is disposed on the diamond substrate; a channel region is disposed on the single-crystal diamond epitaxial film; a source electrode and a drain electrode are disposed on the channel region; the channel region is a hydrogen terminal and includes a two-dimensional hole gas conductive layer, allowing carriers to migrate within the channel; a stress-modulated film is disposed on the source electrode, drain electrode, and channel region; and a gate electrode is disposed on the stress-modulated film. This invention employs thin-film stress to modulate channel carrier mobility. High thin-film stress generates equivalent stress in the single-crystal diamond epitaxial film and the channel region. Under stress, the asymmetry of the single-crystal diamond crystal changes, resulting in energy level splitting. On one hand, the number of carriers in the lower energy levels increases, resulting in a smaller effective mass. On the other hand, the separation of light and heavy holes weakens interband scattering of carriers, increasing the scattering relaxation time. According to the mobility formula μ = qτ / m*, reducing the effective mass (m*) and increasing the scattering relaxation time (τ) improves carrier mobility. Simultaneously, it reduces ionized impurity scattering at the stress-modulated film / hydrogen-terminated diamond interface, further enhancing carrier mobility within the channel and improving the electrical performance of diamond-based devices, including speed, current capacity in the on-state, and turn-off ratio. This invention enhances the performance of conductive channels by increasing carrier mobility, thereby improving the electrical characteristics of transistor devices. Furthermore, the deposited stress-modulated film can serve as a gate dielectric layer to reduce gate leakage current.

[0064] Example 1

[0065] This invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, comprising the following steps:

[0066] 1) The diamond substrate grown by high temperature and high pressure (HPHT) technology was first cleaned with inorganic and then with organic cleaning using the standard diamond substrate cleaning process, and then dried with nitrogen for later use.

[0067] 2) A single-crystal diamond film was deposited on a cleaned diamond substrate using microwave plasma chemical deposition (MPCVD). The plasma power was 1 kW, the chamber pressure was 100 Torr, and the total gas flow rate was 500 sccm. The resulting single-crystal diamond film had a thickness of 1 μm, a resistivity of 100 MΩ·cm, a root mean square surface roughness of 0.45 nm, and a Raman curve half-width of 1.9 cm. -1 The half-peak width of the XRD rocking curve is 29 arcsec.

[0068] 3) The microwave plasma power was controlled to maintain the chamber temperature at 900℃ and the hydrogen flow rate at 50 sccm. The grown single-crystal diamond epitaxial film was hydrogenated for 5 minutes, resulting in a two-dimensional hole gas surface density of 2 × 10⁻⁶. 13 cm -2 The migration rate is 150cm. 2 / V·s.

[0069] 4) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat the sample surface with a layer of AZ5214 photoresist. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the exposed photoresist, leaving the source and drain electrode patterns. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, a 200 nm thick layer of Au was deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120 °C water bath for 5 min. The metal outside the exposed area was then ultrasonically stripped off to obtain the source and drain electrodes.

[0070] 5) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then blow dry. Spin-coat a layer of AZ5214 photoresist onto the source / drain electrodes and the hydrogen-terminated diamond between them. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds, and then treat the sample with a UV / Ozone device for 15 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond, thereby achieving electrical isolation of the device and ensuring that the hydrogen-terminated diamond only exists in the source / drain electrodes and the channel between them. Finally, remove the photoresist from the sample surface with acetone.

[0071] 6) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat the sample surface with a layer of AZ5214 photoresist. Bake the spin-coated single-crystal diamond sample at 95℃ for 90s. Expose it to UV light for 4s using a pre-designed mask, followed by 30s of development to remove the exposed photoresist, leaving the stress-modulated thin film pattern. Deposit a 52nm silicon oxide stress-modulated thin film on the source / drain electrodes and the hydrogen-terminated diamond between them using magnetron sputtering (SD). The magnetron sputtering conditions were: power 50W, chamber pressure 0.5Pa, Ar flow rate 30sccm, and time 15min. The sputtering target was a 99.9% pure silicon oxide target.

[0072] 7) Inject P using an ion implanter + Ions, ion energy 40 keV, ion concentration 2 × 10⁻⁶ 16 cm -2 After stripping the photoresist, the designed stress-modulated thin film pattern was obtained. An annealing process was then performed at 900℃ for 30 seconds. After treatment, the compressive stress of the silicon oxide film was 1 GPa, while the compressive stress in the underlying channel region and the single-crystal diamond epitaxial film was 0.8 GPa. The channel carrier mobility was 1000 cm⁻¹. 2 / V·s.

[0073] 8) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of AZ5214 photoresist onto the sample surface. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the exposed photoresist, leaving the gate electrode pattern. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, 50 nm of Al metal and 100 nm of Au metal were deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a water bath at 120°C for 5 min. The metal outside the exposed area was then ultrasonically peeled off to obtain the gate electrode, thus obtaining a stress-modulated diamond field-effect transistor with enhanced carrier mobility.

[0074] Example 2

[0075] This invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, comprising the following steps:

[0076] 1) The diamond substrate grown by CVD technology was first cleaned with inorganic and then with organic cleaning using the standard diamond substrate cleaning process, and then dried with nitrogen gas for later use.

[0077] 2) A single-crystal diamond film was deposited on a cleaned diamond substrate using microwave plasma chemical deposition (MPCVD). The plasma power was 1.2 kW, the chamber pressure was 100 Torr, and the total gas flow rate was 500 sccm. The resulting single-crystal diamond film had a thickness of 2 μm, a resistivity of 120 MΩ·cm, a root mean square surface roughness of 0.4 nm, and a Raman curve half-width of 1.8 cm. -1 The half-peak width of the XRD rocking curve is 28 arcsec.

[0078] 3) The microwave plasma power was controlled to maintain the chamber temperature at 700℃ and the hydrogen flow rate at 100 sccm. The grown single-crystal diamond epitaxial film was hydrogenated for 20 min, resulting in a two-dimensional hole gas surface density of 1×10⁻⁶. 13 cm -2 The migration rate is 180cm. 2 / V·s.

[0079] 4) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of KXN5735-LO photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 2 seconds, followed by development for 25 seconds to remove the unexposed photoresist, leaving the source and drain electrode patterns. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, a 20 nm thick layer of Ti metal and a 100 nm thick layer of Au metal were deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120 °C water bath for 5 min. The metal outside the exposed area was then ultrasonically stripped to obtain the source and drain electrodes. The source and drain electrodes were then annealed at 500 °C for 3 min under a nitrogen atmosphere to form excellent ohmic contacts.

[0080] 5) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then blow dry. Spin-coat a layer of KXN5735-LO photoresist onto the source / drain electrodes and the hydrogen-terminated diamond between them. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds. Then treat the sample with an oxygen plasma device for 3 minutes at a power of 50W and an oxygen flow rate of 100 sccm to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond, thereby achieving electrical isolation of the device and ensuring that the hydrogen-terminated diamond only exists in the channel between the source / drain electrodes and the channel between them. Finally, remove the photoresist from the sample surface with acetone.

[0081] 6) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Deposit a 45 nm silicon nitride stress-modulated film on the source / drain electrodes and the hydrogen-terminated diamond between them using a plasma-enhanced chemical vapor deposition (PECVD) stage. The PECVD conditions were: reactant gases NH3 and SiH4, carrier gas inert gas such as Ar, SiH4 (diluted to 12% with N2) to NH3 gas flow rate ratio of 2, deposition temperature 350℃, reaction pressure 500 mTorr, RF power 300 W, and frequency 13.65 MHz.

[0082] 7) The thin film was subjected to ultraviolet exposure treatment in an ultraviolet-assisted heat treatment device at a temperature of 400℃ for 5 minutes. After treatment, the compressive stress of the silicon nitride thin film was 1.5 GPa, the compressive stress of the underlying channel region and the single-crystal diamond epitaxial film was 1.2 GPa, and the channel carrier mobility was 1200 cm⁻¹. 2 / V·s.

[0083] 8) Spin-coat a layer of AZ5214 photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the exposed photoresist, leaving the stress-modulated film protective pattern. Then, wet-etch the silicon nitride film using BOE buffer to obtain the designed stress-modulated film pattern.

[0084] 9) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of KXN5735-LO photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 2 seconds, followed by development for 25 seconds to remove the unexposed photoresist, leaving the gate electrode pattern. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4After Pa, Au metal 100 nm was deposited on the sample surface. The deposited diamond sample was removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120°C water bath for 5 min. Then, the metal outside the exposed area was ultrasonically peeled off to obtain the gate electrode, and finally the stress-modulated diamond field-effect transistor with enhanced carrier mobility was obtained.

[0085] Example 3

[0086] This invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, comprising the following steps:

[0087] 1) The diamond substrate grown by CVD technology was first cleaned with inorganic and then with organic cleaning using the standard diamond substrate cleaning process, and then dried with nitrogen gas for later use.

[0088] 2) A single-crystal diamond film was deposited on a cleaned diamond substrate using microwave plasma chemical deposition (MPCVD). The plasma power was 1 kW, the chamber pressure was 100 Torr, and the total gas flow rate was 500 sccm. The resulting single-crystal diamond film had a thickness of 2 μm, a resistivity of 120 MΩ·cm, a root mean square surface roughness of 0.4 nm, and a Raman curve half-width of 1.8 cm. -1 The half-peak width of the XRD rocking curve is 25 arcsec.

[0089] 3) The microwave plasma power was controlled to maintain the chamber temperature at 900℃ and the hydrogen flow rate at 50 sccm. The grown single-crystal diamond epitaxial film was hydrogenated for 5 minutes to obtain a two-dimensional hole gas surface density of 2 × 10⁻⁶. 13 cm -2 The migration rate is 150cm. 2 / V·s.

[0090] 4) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat the sample surface with a layer of AZ5214 photoresist. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the exposed photoresist, leaving the source and drain electrode patterns. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, a 100 nm thick layer of Pd metal was deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120 °C water bath for 5 min. The metal outside the exposed area was then ultrasonically removed to obtain the source and drain electrodes.

[0091] 5) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Deposit a 90 nm stress-modulated film on the source / drain electrodes and the hydrogen-terminated diamond between them using a low-pressure chemical vapor deposition (LPCVD) stage. The LPCVD conditions were: reactant gases NH3 and SiH2Cl2, carrier gas inert gas such as Ar, SiH2Cl2 to NH3 gas flow rate ratio of 8, deposition temperature of 850℃, and reaction pressure of 150 mTorr.

[0092] 6) The thin film was subjected to ultraviolet exposure treatment in an ultraviolet-assisted heat treatment device at a temperature of 400℃ for 5 minutes. After treatment, the compressive stress of the silicon nitride thin film was 0.7 GPa, while the compressive stress of the underlying channel region and the single-crystal diamond epitaxial film was 0.6 GPa. The channel carrier mobility was 800 cm⁻¹. 2 / V·s.

[0093] 7) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of AZ5214 photoresist onto the source / drain electrodes and the hydrogen-terminated diamond between them. Bake the single-crystal diamond sample with photoresist coating at 95°C for 90 seconds. Expose the sample to UV light for 4 seconds using a pre-designed mask, and develop for 30 seconds to remove the exposed photoresist, leaving a stress-modulated thin film (SMC) to protect the pattern. Then, wet-etch the silicon nitride film using BOE buffer to obtain the designed SMC pattern and remove the photoresist. Using the SMC as a mask, treat the sample with a UV / Ozone device for 15 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond, thereby achieving electrical isolation of the device and ensuring that the hydrogen-terminated diamond exists only with the source / drain electrodes and the channel between them.

[0094] 8) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of AZ5214 photoresist onto the sample surface. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 45 seconds to remove the exposed photoresist, leaving the gate electrode pattern. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, Au metal 150 nm was deposited on the sample surface. The deposited diamond sample was removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120°C water bath for 5 min. Then, the metal outside the exposed area was ultrasonically peeled off to obtain the gate electrode, and finally the prepared stress-modulated diamond field-effect transistor with enhanced carrier mobility was obtained.

[0095] Example 4

[0096] This invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, comprising the following steps:

[0097] 1) The diamond substrate grown by high temperature and high pressure (HPHT) technology was first cleaned with inorganic and then with organic cleaning using the standard diamond substrate cleaning process, and then dried with nitrogen for later use.

[0098] 2) A single-crystal diamond film was deposited on a cleaned diamond substrate using microwave plasma chemical deposition (MPCVD). The plasma power was 1 kW, the chamber pressure was 100 Torr, and the total gas flow rate was 500 sccm. The resulting single-crystal diamond film had a thickness of 1 μm, a resistivity of 100 MΩ·cm, a root mean square surface roughness of 0.35 nm, and a Raman curve half-width of 1.5 cm. -1 The half-peak width of the XRD rocking curve is 25 arcsec.

[0099] 3) Control the microwave plasma power to make the chamber temperature 700℃ and maintain the hydrogen flow rate at 50 sccm to hydrogenate the grown single crystal diamond epitaxial film for 20 min to obtain a two-dimensional hole gas conductive layer.

[0100] 4) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of KXN5735-LO photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 2 seconds, followed by development for 25 seconds to remove the unexposed photoresist, leaving the source and drain electrode patterns. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, a 100 nm thick layer of Au metal was deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120 °C water bath for 5 min. The metal outside the exposed area was then ultrasonically removed to obtain the source and drain electrodes.

[0101] 5) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then blow dry. Spin-coat a layer of KXN5735-LO photoresist onto the source / drain electrodes and the hydrogen-terminated diamond between them. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds. Then treat the sample with an oxygen plasma device for 5 minutes at a power of 30W and an oxygen flow rate of 80 sccm to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond, thereby achieving electrical isolation of the device and ensuring that the hydrogen-terminated diamond only exists in the channel between the source / drain electrodes and the channel between them. Finally, remove the photoresist from the sample surface with acetone.

[0102] 6) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of AZ5214 photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose it to UV light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the exposed photoresist, leaving the stress-modulated thin film pattern. Deposit a 150 nm alumina film on the source / drain electrodes and the hydrogen-terminated diamond between them using electron beam evaporation physical vapor deposition (EB-PVD). The EB-PVD conditions are: a base vacuum of 3.7 × 10⁻⁶. -5 Pa, electron beam current intensity 5 A, evaporation chamber pressure 2 × 10⁻⁶ -2 Pa. The target material is alumina particles with a purity of 99%. After peeling, the designed stress-modulated thin film pattern is obtained.

[0103] 7) Subsequently, an annealing process was performed at a temperature of 900℃ for 2 hours. After treatment, the compressive stress of the alumina film was 0.8 GPa, while the compressive stress in the underlying channel region and the single-crystal diamond epitaxial film was 0.6 GPa. The channel carrier mobility was 900 cm⁻¹. 2 / V·s.

[0104] 8) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of KXN5735-LO photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 2 seconds, followed by development for 25 seconds to remove the unexposed photoresist, leaving the gate electrode pattern. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, Al metal 300 nm was deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120°C water bath for 5 min. The metal outside the exposed area was then ultrasonically peeled off to obtain the gate electrode, thus obtaining the prepared stress-modulated diamond field-effect transistor with enhanced carrier mobility.

[0105] Example 5

[0106] This invention provides a method for fabricating a diamond field-effect transistor with stress-modulated enhanced carrier mobility, comprising the following steps:

[0107] 1) The diamond substrate grown by high temperature and high pressure (HPHT) technology was first cleaned with inorganic and then with organic cleaning using the standard diamond substrate cleaning process, and then dried with nitrogen for later use.

[0108] 2) A single-crystal diamond film was deposited on a cleaned diamond substrate using microwave plasma chemical deposition (MPCVD). The plasma power was 1 kW, the chamber pressure was 100 Torr, and the total gas flow rate was 500 sccm. The resulting single-crystal diamond film had a thickness of 3 μm, a resistivity of 110 MΩ·cm, a root mean square surface roughness of 0.3 nm, and a Raman curve half-width of 1.7 cm. -1 The half-peak width of the XRD rocking curve is 25 arcsec.

[0109] 3) Control the microwave plasma power to make the chamber temperature 800℃ and maintain the hydrogen flow rate at 100sccm to hydrogenate the grown single crystal diamond epitaxial film for 30 minutes to obtain a two-dimensional hole gas conductive layer.

[0110] 4) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat the sample surface with a layer of AZ5214 photoresist. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the unexposed photoresist, leaving the source and drain electrode patterns. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, a 100 nm thick layer of Au metal was deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120 °C water bath for 5 min. The metal outside the exposed area was then ultrasonically removed to obtain the source and drain electrodes.

[0111] 5) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then blow dry. Spin-coat a layer of AZ5214 photoresist onto the source / drain electrodes and the hydrogen-terminated diamond between them. Bake the single-crystal diamond sample with the photoresist coated at 95°C for 90 seconds, and then treat the sample with a UV / Ozone device for 15 minutes to convert the exposed hydrogen-terminated diamond into oxygen-terminated diamond, thereby achieving electrical isolation of the device and ensuring that the hydrogen-terminated diamond only exists in the source / drain electrodes and the channel between them. Finally, remove the photoresist from the sample surface with acetone.

[0112] 6) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Deposit a 300 nm hafnium oxide film on the source / drain electrodes and the hydrogen-terminated diamond between them using atomic layer deposition (ALD). The reaction gases included Hf(NMe2)4 and pure water, the carrier gas included nitrogen, and the deposition temperature was 350 °C.

[0113] 7) Subsequently, an annealing process was performed at 800℃ for 1 hour. After treatment, the compressive stress of the hafnium oxide film was 2 GPa, while the compressive stress in the lower channel region and the single-crystal diamond epitaxial film was 1.8 GPa. The channel carrier mobility was 1600 cm⁻¹. 2 / V·s. A layer of AZ5214 photoresist is spin-coated onto the sample surface. The spin-coated single-crystal diamond sample is baked at 95℃ for 90s. Ultraviolet lithography is then performed using a designed mask for 4s, followed by development for 30s to remove the exposed photoresist, leaving a stress-modulated thin film protective pattern. Subsequently, a hafnium oxide thin film is wet-etched to obtain the designed stress-modulated thin film pattern.

[0114] 8) Clean the sample ultrasonically with acetone, isopropanol, and deionized water, and then dry it. Spin-coat a layer of AZ5214 photoresist onto the sample surface. Bake the spin-coated single-crystal diamond sample at 95°C for 90 seconds. Expose the sample to ultraviolet light using a pre-designed mask for 4 seconds, followed by development for 30 seconds to remove the unexposed photoresist, leaving the gate electrode pattern. Place the photolithographically patterned sample in an electron beam evaporation apparatus and evacuate the background vacuum to 5 × 10⁻⁶. -4 After Pa, 100 nm of Al metal and 150 nm of Au metal were deposited on the sample surface. The deposited diamond sample was then removed, immersed in N-methylpyrrolidone (NMP) solution, and bathed in a 120°C water bath for 5 min. The metal outside the exposed area was then ultrasonically peeled off to obtain the gate electrode, thus obtaining a stress-modulated diamond field-effect transistor with enhanced carrier mobility.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A diamond field-effect transistor, characterized in that, include: Diamond substrate (1), single crystal diamond epitaxial film (2), source electrode (3), drain electrode (4), stress-controlled film (6) and gate electrode (7). The single-crystal diamond epitaxial film (2) is disposed on the diamond substrate (1); the single-crystal diamond epitaxial film (2) is provided with a hydrogen terminal region and an oxygen terminal region (8), wherein the hydrogen terminal region is a channel region (5) composed of a two-dimensional hole gas conductive layer. The source electrode (3) and the drain electrode (4) are respectively provided at both ends of the channel region (5). The source electrode (3), the drain electrode (4), and the channel region (5) without source and drain electrodes are provided with the stress control film (6). The stress control film (6) is used to control the stress of the single crystal diamond epitaxial film (2) and the channel region (5) below it, so as to improve the carrier mobility of the two-dimensional hole gas conductive layer. The gate electrode (7) is disposed on the stress-regulating film (6) and the oxygen terminal region (8).

2. The diamond field-effect transistor according to claim 1, characterized in that, The stress-regulating thin film (6) is made of SiN. x SiO2, Al2O3, HfO2, ZrO2, diamond-like carbon, or other materials with a work function greater than or equal to 5 eV.

3. The diamond field-effect transistor according to claim 1, characterized in that, The thickness of the stress-regulating film (6) is 1 nm to 5000 nm.

4. A diamond field-effect transistor according to claim 1, characterized in that, The internal compressive stress of the stress-regulating membrane (6) is 1 MPa to 10 GPa.

5. A diamond field-effect transistor according to claim 1, characterized in that, The compressive stress in the single-crystal diamond epitaxial film (2) below the stress-controlled film (6) is 10 MPa to 5 GPa.

6. A diamond field-effect transistor according to claim 1, characterized in that, The width of the channel region (5) is 5 nm to 100 μm, and the carrier concentration in the channel is 1 × 10⁻⁶. 12 cm -2 ~5×10 14 cm -2 The migration rate is 20cm. 2 / V·s~2500cm 2 / V·s.

7. A diamond field-effect transistor according to claim 1, characterized in that, The source electrode (3) and the drain electrode (4) are made of Au, Pd, Ir, Pt or Ti; the gate electrode (7) is made of Al, Zr, Hf or Mo.

8. A method for fabricating a diamond field-effect transistor according to claim 1, characterized in that, Includes the following steps: Homogeneous epitaxial single-crystal diamond films are formed on cleaned diamond substrates (1) to obtain single-crystal diamond epitaxial films (2). The single-crystal diamond epitaxial film (2) is hydrogenated to obtain a two-dimensional hole gas conductive layer; Source electrode and drain electrode patterns are formed on the two-dimensional hole gas conductive layer, and source electrode metal and drain electrode metal are deposited accordingly. Ohmic contact between source electrode (3) and drain electrode (4) is obtained by stripping technique. Photoresist is applied to the source electrode (3), drain electrode (4) and the channel region (5) between them, and oxygen termination is performed using photolithography to form an oxygen termination region (8) to achieve electrical isolation of the device. A stress-controlled thin film (6) is deposited on the source electrode (3), the drain electrode (4), and the channel region (5) between them; Adjust the magnitude of the internal compressive stress of the stress-regulating membrane (6) to meet the preset requirements; A gate electrode (7) pattern is formed on the stress-controlled thin film (6) and the oxygen terminal region (8). After depositing the gate electrode metal, the gate electrode (7) is obtained by stripping.

9. The method for fabricating a diamond field-effect transistor according to claim 8, characterized in that, In the step of depositing the stress-modulated thin film (6) on the source electrode (3), the drain electrode (4), and the channel region (5) between them, The deposition methods include electron beam evaporation, sputtering, atomic layer deposition, plasma-enhanced chemical vapor deposition, or low-pressure chemical vapor deposition.

10. The method for fabricating a diamond field-effect transistor according to claim 8, characterized in that, In the step of adjusting the internal compressive stress of the stress-regulating membrane (6) to meet the preset requirements, The control methods include ion implantation, thermal annealing, multilayer deposition, or ultraviolet-assisted heat treatment processes.

Images