N-Type Carbon-Based Field-Effect Transistor and Its Preparation Method

Abstract

This application relates to the technical field of semiconductor devices, and particularly relates to an N-type carbon-based field effect transistor and a preparation method thereof. The preparation method of the N-type carbon-based field effect transistor includes: preparing a basic carbon-based field effect transistor with a bottom gate structure, where the bottom gate structure includes a conductive channel layer, and the conductive channel layer is a carbon-based material; performing a purification treatment and heating on the basic carbon-based field effect transistor to remove impurities and groups of the basic carbon-based field effect transistor; soaking the basic carbon-based field effect transistor in a second solution to generate a molecular film on the surface of the conductive channel layer; performing a drying treatment on the soaked basic carbon-based field effect transistor to obtain the N-type carbon-based field effect transistor. By enabling organic molecules to adsorb on the surface of the carbon-based material through π-π non-covalent interactions to form a molecular film, and efficiently providing electrons, electron doping of the carbon-based material is achieved while maintaining the integrity of its atomic structure, and finally the N-type carbon-based field effect transistor is prepared.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and particularly to an N-type carbon-based field effect transistor and a preparation method thereof. Background Art

[0002] Traditional silicon-based semiconductor technology has approached its physical limits (such as quantum tunneling effect and short-channel effect), making it difficult to further reduce the device size. Carbon-based materials (such as graphene, carbon nanotubes, graphdiyne, etc.) have higher carrier mobilities (for example, the mobility of carbon nanotubes can be more than 10 times that of silicon), providing the possibility for the development of nano-scale or even molecular-scale devices. At the same time, carbon materials can be bent and stretched, making them suitable for flexible electronic devices and wearable devices.

[0003] Oxygen or water molecules are easily adsorbed on the surface of carbon-based materials. These molecules, as electron acceptors, capture electrons from the carbon-based materials, resulting in holes becoming the majority carriers, thus making the field effect transistors constructed with carbon-based materials exhibit P-type dominant characteristics (hole conduction). The stable fabrication of N-type carbon-based field effect transistors is a prerequisite for constructing carbon-based CMOS circuits. In related technologies, generally, methods such as electric field regulation or chemical doping are used to achieve the regulation of the conductive characteristics of carbon-based field effect transistors. However, the process of electric field regulation is relatively complex, and chemical doping destroys the atomic structure of carbon-based materials, reducing their conductive characteristics.

[0004] Therefore, there is an urgent need to propose a new method to solve the above technical problems, to simply, efficiently, and at low cost achieve the preparation of N-type carbon-based field effect transistors while keeping the atomic structure of carbon-based materials intact. Summary of the Invention

[0005] This application discloses an N-type carbon-based field effect transistor and a preparation method thereof. First, a basic carbon-based field effect transistor is subjected to a cleaning treatment, and then, by virtue of the non-covalent interaction, organic molecules in the second solution are adsorbed on the surface of the carbon-based material to form a molecular film, so as to isolate the hole doping of the carbon-based material by water and oxygen in the air, and efficiently provide electrons, thereby realizing the electron doping of the carbon-based material while maintaining the integrity of its atomic structure, and simply and efficiently achieving the preparation of the N-type carbon-based field effect transistor.

[0006] In some embodiments, a method for fabricating an N-type carbon-based field-effect transistor is provided, including: fabricating a basic carbon-based field-effect transistor with a bottom gate structure, where the bottom gate structure includes a conductive channel layer made of a carbon-based material; performing a cleaning treatment on the basic carbon-based field-effect transistor using a first solution, and then performing a heating treatment on the cleaned basic carbon-based field-effect transistor to remove impurities and groups on the basic carbon-based field-effect transistor; immersing the basic carbon-based field-effect transistor in a second solution to form a molecular film on the surface of the conductive channel layer; and performing a drying treatment on the immersed basic carbon-based field-effect transistor to obtain an N-type carbon-based field-effect transistor.

[0007] By using the method for fabricating an N-type carbon-based field-effect transistor provided in the embodiments of the present application, a basic carbon-based field-effect transistor can be fabricated using a carbon-based material as the conductive channel layer. Performing a cleaning treatment on the basic carbon-based field-effect transistor using a first solution and then performing a heating treatment on the cleaned basic carbon-based field-effect transistor can remove impurities and groups on the surface of the carbon-based material, enabling the conjugated structure on the surface of the carbon-based material to be fully exposed. By immersing the basic carbon-based field-effect transistor in the second solution, organic molecules in the second solution can undergo non-covalent interactions with the conjugated structure on the surface of the carbon-based material to form a molecular film, isolating water and oxygen in the air from hole doping of the carbon-based material and efficiently providing electrons, thereby achieving electron doping of the carbon-based material while maintaining the integrity of its atomic structure, and finally fabricating an N-type carbon-based field-effect transistor.

[0008] Optionally, fabricating the basic carbon-based field-effect transistor with a bottom gate structure includes: providing a substrate layer, where the substrate layer is a doped silicon wafer with a silicon dioxide layer on its surface; integrating a carbon-based material on the surface of the silicon dioxide layer to form a conductive channel layer, and the carbon-based material is at least one of graphdiyne, graphene nanoribbon, and carbon nanotube with semiconductor properties; and fabricating a source electrode and a drain electrode on the carbon-based material using a micro-nano processing technique.

[0009] Optionally, performing a cleaning treatment on the basic carbon-based field-effect transistor using a first solution and then performing a heating treatment on the cleaned basic carbon-based field-effect transistor includes: preparing a first solution, where the organic solution in the first solution is at least one of N-methylpyrrolidone, tetrahydrofuran, chloroform, dichloromethane, methanol, ethanol, and toluene; placing the basic carbon-based field-effect transistor in the first solution, taking it out after soaking for a first preset time; and performing a heating treatment on the soaked basic carbon-based field-effect transistor to remove impurities and groups on the surface of the carbon-based material, and the groups include at least one of hydroxyl group, carboxyl group, amino group, and methyl group.

[0010] In this way, the impurities and groups on the surface of the carbon-based material of the basic carbon-based field-effect transistor can be dissolved by the organic solution in the first solution, and through heat treatment, the impurities and groups on the surface of the carbon-based material can be further removed, so that the conjugated structure can be fully exposed, providing good conditions for the subsequent formation of the molecular film.

[0011] Optionally, the first preset time is from 1 minute to 5 minutes, the temperature of the first solution is within the first temperature range, and the first temperature range is from 50 °C to 80 °C.

[0012] In this way, by controlling the temperature and soaking time of the first solution, the impurities and groups on the surface of the carbon-based material of the basic carbon-based field-effect transistor can be fully dissolved in the organic solution in the first solution, thereby improving the effect of removing the impurities and groups on the surface of the carbon-based material.

[0013] Optionally, before performing the heat treatment on the soaked basic carbon-based field-effect transistor, it further includes: soaking the basic carbon-based field-effect transistor in a third solution and a fourth solution in sequence, the third solution is an acetone solution, and the fourth solution is deionized water.

[0014] In this way, the organic impurities on the surface of the carbon-based material can be further dissolved by the acetone solution, thereby improving the cleaning effect. The deionized water can be used to remove the residual acetone solution on the surface of the basic carbon-based field-effect transistor, improving the purity of the surface of the basic carbon-based field-effect transistor.

[0015] Optionally, performing the heat treatment on the soaked basic carbon-based field-effect transistor includes: providing an annealing furnace, the inside of the annealing furnace is vacuum or an inert gas, and the inert gas is at least one of nitrogen and argon; placing the basic carbon-based field-effect transistor in the annealing furnace for heating, and the temperature of the annealing furnace is within the second temperature range, and the second temperature range is from 150 °C to 550 °C.

[0016] In this way, the impurities and groups on the surface of the carbon-based material can undergo a thermal decomposition reaction and decompose into small molecule gases at high temperature, so as to detach from the surface of the carbon-based material, making the conjugated structure can be fully exposed, providing good conditions for the subsequent formation of the molecular film.

[0017] Optionally, soaking the basic carbon-based field-effect transistor in the second solution includes: preparing the second solution, and the organic solution in the second solution is at least one of acridine orange, methylene blue, rhodamine derivatives and cyanine derivatives containing an electron donor group; placing the basic carbon-based field-effect transistor in the second solution and taking it out after soaking for the second preset time, and the second preset time is greater than or equal to 5 seconds.

[0018] In this way, the surface of the organic molecules in the organic solution can be utilized A conjugated structure, on the surface of the carbon-based material Non-covalent interactions occur between the conjugated structures Non-covalent interactions can achieve the self-adsorption of organic molecules, complete the functional modification of the carbon-based material, and generate a molecular film.

[0019] Optionally, a drying process is performed on the soaked basic carbon-based field effect transistor, including: purging the surface of the basic carbon-based field effect transistor with a clean gas to remove the residual second solution on the surface of the basic carbon-based field effect transistor, and the clean gas is at least one of oxygen, nitrogen, and argon.

[0020] In this way, the excess solution on the surface of the carbon-based field effect transistor can be removed, and the carbon-based field effect transistor can be kept dry.

[0021] In some embodiments, an N-type carbon-based field effect transistor is provided, including: a substrate layer, which is a doped silicon wafer with a silicon dioxide layer covering its surface; a conductive channel layer, which is disposed above the silicon dioxide layer, and the conductive channel layer is a carbon-based material; an electrode, which is disposed above the conductive channel layer; a molecular film, which covers a first region above the conductive channel layer, and the first region is the region on the surface of the conductive channel layer except the electrode, and the molecular film includes organic molecules.

[0022] Optionally, the conductive channel layer is at least one of graphdiyne, graphene nanoribbon, and carbon nanotube having semiconductor characteristics.

[0023] It can be understood that for the beneficial effects that the above-provided N-type carbon-based field effect transistor can achieve, reference can be made to the beneficial effects in the preparation method of the N-type carbon-based field effect transistor and any of its optional implementation manners, which will not be elaborated here. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic flow chart of the preparation method of the N-type carbon-based field effect transistor provided by the embodiment of the present application;

[0026] Figure 2 It is a schematic flow chart of the preparation method of the basic carbon-based field effect transistor provided by the embodiment of the present application;

[0027] Figure 3 It is a schematic flow chart of the purification treatment of the basic carbon-based field effect transistor provided by the embodiment of the present application;

[0028] Figure 4 Structural diagram of the N-type carbon-based field-effect transistor provided by the embodiment of the present application;

[0029] Figure 5 Example diagram of the experimental test circuit provided by the embodiment of the present application;

[0030] Figure 6 Example diagram of the transfer characteristic curve of the basic carbon-based field-effect transistor provided by the embodiment of the present application;

[0031] Figure 7 Example diagram of the transfer characteristic curve of the N-type carbon-based field-effect transistor provided by the embodiment of the present application.

[0032] Reference numerals:

[0033] 1. Substrate layer; 11. Doped silicon wafer; 12. Silicon dioxide layer; 2. Conductive channel layer; 3. Electrode; 4. Molecular thin film. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all embodiments. Based on the embodiments of the present application, other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0035] Hereinafter, terms such as "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0036] In addition, in the present application, orientation terms such as "upper", "lower", "inner", "outer", etc. are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, which are used for relative description and clarification, and they may change accordingly with the change of the orientation of the components placed in the accompanying drawings.

[0037] For the convenience of understanding the technical solutions of the application, the related technologies involved in the present application will be described first below.

[0038] A carbon-based field effect transistor is a device that uses carbon materials with semiconductor properties as a conductive channel to realize the function of a field effect transistor. A voltage is applied between the gate and the source to form an electric field perpendicular to the conductive channel. The electric field changes the type (electrons or holes) and concentration of carriers in the conductive channel through capacitive coupling. Under the action of the voltage between the source and the drain, the carriers flow along the channel to form a current.

[0039] Carbon-based materials (graphyne, carbon nanotubes, graphene) have high carrier mobility, but due to their small size and large specific surface area, they are very easy to adsorb water and oxygen molecules in the air. As electron acceptors, water and oxygen molecules will take electrons from carbon-based materials, making holes the majority carriers, so that field effect transistors based on carbon-based materials show P-type dominant characteristics. This characteristic makes the preparation of N-type carbon-based field effect transistors challenging.

[0040] The N-type conductive properties of carbon-based field effect transistors can be regulated by electric field regulation or chemical doping, but the electric field regulation process is relatively complicated, and chemical doping destroys the atomic structure of carbon-based materials and reduces their conductive properties. In order to solve the problems existing in the above-mentioned related technologies, the present application embodiment provides an N-type carbon-based field effect transistor and a preparation method thereof, which utilizes the molecular Non-covalent interactions adsorb organic molecules on the surface of carbon-based materials to form a molecular film to isolate the hole doping of carbon-based materials by water and oxygen in the air, and efficiently provide electrons, thereby achieving electron doping of carbon-based materials while maintaining the integrity of their atomic structure, and ultimately preparing N-type carbon-based field effect transistors.

[0041] Figure 1 The schematic diagram of the process for preparing the N-type carbon-based field effect transistor provided in the embodiment of the present application is as follows: Figure 1 The preparation method of the N-type carbon-based field effect transistor of the embodiment of the present application is described in detail. Figure 1 As shown, the method for preparing an N-type carbon-based field effect transistor includes steps S100 to S400.

[0042] Step S100: preparing a basic carbon-based field effect transistor with a bottom-gate structure.

[0043] In some embodiments, the basic carbon-based field effect transistor is a bottom gate structure. In the bottom gate structure, the gate is located on the substrate layer, an insulating layer is deposited on the gate, and a conductive channel layer is formed on the insulating layer, the conductive channel layer is a carbon-based material, and a source and a drain are made on the conductive channel layer, thereby obtaining a basic carbon-based field effect transistor with a bottom gate structure.

[0044] Figure 2 A schematic diagram of a process for preparing a basic carbon-based field effect transistor provided in an embodiment of the present application, such as Figure 2As shown, the preparation of a bottom-gate structure basic carbon-based field-effect transistor includes steps S101 to S103.

[0045] Step S101: Provide a substrate layer.

[0046] In some embodiments, the substrate layer is a doped silicon wafer with a silicon dioxide layer covering its surface. During the preparation of the substrate layer, a silicon dioxide insulating layer is grown on the surface of a clean doped silicon wafer by any one of thermal oxidation, deposition, and epitaxial growth methods, thereby obtaining the substrate layer.

[0047] Step S102: Integrate a carbon-based material on the surface of the silicon dioxide layer to form a conductive channel layer.

[0048] In some embodiments, the carbon-based material can be at least one of graphdiyne, graphene nanoribbon, and carbon nanotube with semiconductor characteristics. Among them, graphdiyne is a new carbon material with rich carbon chemical bonds and a large conjugated system. Graphene is a two-dimensional carbon nanomaterial composed of carbon atoms in a hexagonal shape. Carbon nanotubes are seamless and hollow tubular structures formed by carbon atoms.

[0049] When the carbon-based material is a carbon nanotube, chemical vapor deposition can be used to integrate the carbon-based material on the surface of the silicon dioxide layer. In addition, the carbon nanotube dispersion can also be deposited into a film by spin coating, spraying, dip coating, or dip-coating and pulling methods to form a conductive channel layer.

[0050] When the carbon-based material is graphene or graphdiyne, the carbon-based material can be peeled off from the surface of graphite by mechanical exfoliation and transferred to the surface of the silicon dioxide layer to form a conductive channel layer. In addition, chemical deposition can also be used to grow graphene or graphdiyne on the surface of a metal substrate at high temperature using a carbon-containing gas, and then transfer it to the surface of the silicon dioxide layer to form a conductive channel layer. The method of integrating the carbon-based material on the surface of the silicon dioxide layer in this application is not specifically limited.

[0051] Step S103: Use micro-nano processing technology to prepare source and drain electrodes on the carbon-based material.

[0052] In some embodiments, a layer of photoresist is spin-coated on the surface of the carbon-based material. Through ultraviolet exposure process means (such as using a mask plate for ultraviolet exposure), a photochemical reaction occurs in the photoresist in a specific area. After exposure, the photoresist is developed, and the photoresist in the areas where the source and drain electrodes need to be formed is removed. Then, physical vapor deposition is used to deposit a metal (such as gold, palladium, titanium, chromium, etc.) on the surface of the carbon-based material. The remaining photoresist is removed by a degluing process to prepare the source and drain electrodes on the carbon-based material.

[0053] Step S200: Purify the basic carbon-based field-effect transistor using the first solution, and perform a heating treatment on the purified basic carbon-based field-effect transistor.

[0054] In some embodiments, there are impurities on the surface of the basic carbon-based field-effect transistor. These impurities can affect the adsorption force of organic molecules on the surface of the carbon-based material, reduce the efficiency and quality of the organic molecule adsorption film formation, and reduce the charge transfer efficiency between molecules. Purifying and heating the basic carbon-based field-effect transistor using the first solution can remove impurities and groups, so that the conjugated structure on the surface of the carbon-based material can be fully exposed, providing good conditions for the subsequent formation of a molecular thin film.

[0055] Figure 3 The flowchart of purifying the basic carbon-based field-effect transistor provided by the embodiment of the present application is shown in Figure 3 As shown, purifying the basic carbon-based field-effect transistor includes steps S201 to S203.

[0056] Step S201: Prepare the first solution.

[0057] In some embodiments, the organic solution in the first solution is at least one of N-methylpyrrolidone, tetrahydrofuran, chloroform, dichloromethane, methanol, ethanol, and toluene. In this way, the organic solution in the first solution can dissolve some of the organic substances on the surface of the basic carbon-based field-effect transistor, achieving the purpose of removing impurities.

[0058] Step S202: Place the basic carbon-based field-effect transistor in the first solution, and take it out after soaking for a first preset time.

[0059] In some embodiments, control the temperature of the first solution within a first temperature range, place the basic carbon-based field-effect transistor in the first solution, and take it out after soaking for a first preset time. Among them, the first preset time is 1 minute to 5 minutes, and the first temperature range is 50 degrees Celsius to 80 degrees Celsius.

[0060] Exemplarily, set the temperature of the first solution to 55 degrees Celsius, place the basic carbon-based field-effect transistor in the first solution and soak it for 2 minutes, and then take it out to remove the impurities on the surface of the basic carbon-based field-effect transistor.

[0061] Step S203: Perform a heating treatment on the soaked basic carbon-based field-effect transistor.

[0062] In some embodiments, due to the certain adsorption force of impurities and groups on the surface of the basic carbon-based field-effect transistor, by performing a heating treatment on the basic carbon-based field-effect transistor, the thermal motion of molecules can be intensified, enabling the impurities and groups to obtain sufficient energy to overcome the adsorption force, and thus desorb and decompose from the surface of the carbon-based material. The decomposed impurities and groups are separated from the basic carbon-based field-effect transistor in a gaseous form to remove the impurities and groups on the surface of the carbon-based material. Among them, the groups include at least one of hydroxyl group, carboxyl group, amino group, and methyl group.

[0063] In some embodiments, before performing the heating treatment on the soaked basic carbon-based field-effect transistor, the basic carbon-based field-effect transistor also needs to be soaked in a third solution and a fourth solution in sequence, where the third solution is an acetone solution and the fourth solution is deionized water.

[0064] It should be understood that acetone is an organic solvent with strong dissolving ability, which can effectively dissolve the grease, organic residues, and some polymer impurities on the surface of the basic carbon-based field-effect transistor. Deionized water is a high-purity water that can remove the water-soluble impurities on the surface of the basic carbon-based field-effect transistor. In this way, by soaking the basic carbon-based field-effect transistor in the third solution and the fourth solution in sequence, the cleanliness of the basic carbon-based field-effect transistor can be further improved.

[0065] In some embodiments, an annealing furnace can be used to perform the heating treatment on the basic carbon-based field-effect transistor. First, provide an annealing furnace, and the inside of the annealing furnace is in a vacuum or an inert gas, and the inert gas is at least one of nitrogen and argon. In this way, it can prevent the carbon-based material from undergoing an oxidation reaction with oxygen at high temperatures, resulting in changes in the structure and properties of the carbon-based material. In a specific implementation manner, providing the annealing furnace specifically includes: filling the annealing furnace with an inert gas, but the inert gas remains in a flowing state, and the gas enters from one end of the annealing furnace and exits from the other end. In another specific implementation manner, providing the annealing furnace specifically includes: making the inside of the annealing furnace in a vacuum state.

[0066] Further, place the basic carbon-based field-effect transistor in the annealing furnace for heating. The temperature of the annealing furnace is within a second temperature range, and the second temperature range is from 150 degrees Celsius to 550 degrees Celsius. In this way, the impurities and groups on the surface of the carbon-based material can undergo a thermal decomposition reaction and decompose into small-molecule gases at high temperatures, so as to separate from the surface of the carbon-based material, enabling the conjugated structure on the surface of the carbon-based material to be fully exposed, providing good conditions for the subsequent formation of a molecular film.

[0067] Step S300: Soak the basic carbon-based field-effect transistor in the second solution.

[0068] In some embodiments, a second solution needs to be prepared. The organic solution in the second solution is at least one of acridine orange, methylene blue, rhodamine derivatives, and cyanine derivatives containing an electron donor group. The basic carbon-based field-effect transistor is placed in the second solution and taken out after soaking for a second preset time, and the second preset time is greater than or equal to 5 seconds.

[0069] By soaking the basic carbon-based field-effect transistor in the second solution, the organic molecules in the second solution can be adsorbed on the surface of the carbon-based material through non-covalent interactions between molecules to form a molecular film. In this way, through the functional modification of the carbon-based material, the precise functionalization of the carbon-based material by organic molecules can be realized, effectively avoiding the drawback of non-selective coverage. Specifically, the organic solution in the second solution is a solution containing a conjugated structure and an electron donor group. In particular, the organic solution in the second solution is an organic solution containing a conjugated structure and an electron donor group. Conjugated structure and electron donor group solution.

[0070] Specifically, the organic solution in the second solution is an organic solution containing a conjugated structure and an electron donor group.

[0071] Step S400: Perform a drying process on the soaked basic carbon-based field-effect transistor.

[0072] Since the surface of the soaked basic carbon-based field-effect transistor remains the second solution, it is necessary to perform a drying process on the soaked basic carbon-based field-effect transistor to obtain an N-type carbon-based field-effect transistor.

[0073] In some embodiments, the surface of the basic carbon-based field-effect transistor is purged with a clean gas to remove the second solution remaining on the surface of the basic carbon-based field-effect transistor. The clean gas is at least one of oxygen, nitrogen, and argon. In this way, the excess solution on the surface of the carbon-based field-effect transistor can be removed, and the carbon-based field-effect transistor can be kept dry.

[0074] As can be seen from the above technical solutions, the preparation method of the N-type carbon-based field-effect transistor provided by the embodiments of the present application can use the carbon-based material as a conductive channel layer to generate a basic carbon-based field-effect transistor. Using the first solution to perform a cleaning process and a heating process on the basic carbon-based field-effect transistor can remove impurities and groups on the surface of the carbon-based material, so that the conjugated structure on the surface of the carbon-based material can be fully exposed. By soaking the basic carbon-based field-effect transistor in the second solution, the organic molecules in the second solution can have non-covalent interactions with the conjugated structure on the surface of the carbon-based material to form a molecular film, so as to isolate the hole doping of the carbon-based material by water and oxygen in the air and efficiently provide electrons, thereby realizing the electron doping of the carbon-based material while maintaining the integrity of its atomic structure, and finally preparing an N-type carbon-based field-effect transistor. Conjugated structure can be fully exposed. By soaking the basic carbon-based field-effect transistor in the second solution, the organic molecules in the second solution can be Conjugated structure occurs Non-covalent interactions to form a molecular film to isolate the hole doping of the carbon-based material by water and oxygen in the air and efficiently provide electrons, thereby realizing the electron doping of the carbon-based material while maintaining the integrity of its atomic structure, and finally preparing an N-type carbon-based field-effect transistor.

[0075] Figure 4 This is a structural diagram of the N-type carbon-based field-effect transistor provided by the embodiment of the present application.

[0076] The embodiment of the present application also provides an N-type carbon-based field-effect transistor. As Figure 4 shown, the N-type carbon-based field-effect transistor includes a substrate layer 1, a conductive channel layer 2, an electrode 3, and a molecular thin film 4. Among them, the substrate layer 1 is a doped silicon wafer 11 with a silicon dioxide layer 12 covering the surface, the conductive channel layer 2 is disposed above the silicon dioxide layer 12, and the conductive channel layer 2 is a carbon-based material; the electrode 3 is disposed on the conductive channel layer; the molecular thin film 4 covers the first region of the conductive channel layer 2, and the first region is the region on the surface of the conductive channel layer 2 except for the electrode 3. The molecular thin film 4 includes organic molecules containing a conjugated structure and an electron donor group. The conductive channel layer 2 is at least one of graphdiyne, graphene nanoribbon, and carbon nanotube having semiconductor characteristics.

[0077] It can be understood that for the beneficial effects that can be achieved by the above-provided N-type carbon-based field-effect transistor, reference can be made to the beneficial effects in the preparation method of the N-type carbon-based field-effect transistor and any optional implementation manner thereof, which will not be elaborated here.

[0078] Figure 5 This is an example diagram of the experimental test circuit provided by the embodiment of the present application, Figure 6 This is an example diagram of the transfer characteristic curve of the basic carbon-based field-effect transistor provided by the embodiment of the present application, Figure 7 This is an example diagram of the transfer characteristic curve of the N-type carbon-based field-effect transistor provided by the embodiment of the present application. To make the technical solutions and technical effects of the present invention clearer, the following combines Figure 5 、 Figure 6 and Figure 7 to further elaborate on the present invention in detail.

[0079] Step 1: Prepare a basic carbon-based field-effect transistor with a bottom-gate structure. Among them, the carbon-based material of the basic carbon-based field-effect transistor is carbon nanotube having semiconductor characteristics.

[0080] Step 2: Clean the basic carbon-based field-effect transistor with ethanol, acetone, and deionized water in sequence.

[0081] Step 3: Put the cleaned basic carbon-based field-effect transistor into an annealing furnace and anneal it in a vacuum environment at 300 degrees Celsius for 60 minutes.

[0082] Step 4: Connect the experimental test circuit and test the transfer characteristics of the basic carbon-based field-effect transistor.

[0083] As Figure 5As shown, the connection of the experimental test circuit in Step 4 specifically includes: connecting the source S of the basic carbon-based field-effect transistor to the negative pole of the first power supply V1, connecting the drain D of the basic carbon-based field-effect transistor to the positive pole of the first power supply V1, and setting an ammeter between the positive pole of the first power supply V1 and the drain D. Connect the gate G of the basic carbon-based field-effect transistor to the negative pole of the second power supply V2, and connect the positive pole of the second power supply V2 and the drain to the first node N, and the first node N is grounded.

[0084] During the test, the source voltage and the drain voltage are fixed at -0.5V, and the gate voltage starts from -30V and gradually increases to 30V in steps of 0.5V. Record the current values at different gate voltages. Plot the test curve of the basic carbon-based field-effect transistor, and then obtain Figure 6 the transfer characteristic curve of the basic carbon-based field-effect transistor in Figure 6 In , at a negative gate voltage (-20V), the hole transfer current is much larger than the electron transfer current at a positive gate voltage (20V). In addition, at zero gate voltage, the conductive channel is mainly hole-conductive.

[0085] Step 5: Immerse the annealed basic carbon-based field-effect transistor in Step 3 in a solution containing rhodamine B, take it out after 15 seconds to form a molecular film.

[0086] Step 6: Blow dry the liquid remaining on the surface of the basic carbon-based field-effect transistor with nitrogen to obtain an N-type carbon-based field-effect transistor.

[0087] Step 7: Connect the experimental test circuit to test the transfer characteristics of the N-type carbon-based field-effect transistor.

[0088] According to the circuit connection method and voltage adjustment method in Step 4, test the transfer characteristics of the N-type carbon-based field-effect transistor, plot the test curve of the N-type carbon-based field-effect transistor, and then obtain Figure 7 the transfer characteristic curve of the N-type carbon-based field-effect transistor in Figure 7 In , at a negative gate voltage (-20V), the hole transfer current is much smaller than the electron transfer current at a positive gate voltage (20V). In addition, at zero gate voltage, the conductive channel is mainly electron-conductive.

[0089] By comparing Figure 6 the basic carbon-based field-effect transistor in Figure 7The transfer characteristic curve of the N-type carbon-based field-effect transistor shows that, compared with the carbon-based field-effect transistor without an organic molecular film, the electron transport characteristics of the carbon-based field-effect transistor with an organic molecular film are greatly improved. It can be seen that the molecular film can isolate the hole doping of the carbon-based material by water and oxygen in the air, and efficiently provide electrons, thereby realizing the electron doping of the carbon-based material while maintaining the integrity of its atomic structure, and simply and efficiently realizing the preparation of the N-type carbon-based field-effect transistor.

[0090] It should be noted that those skilled in the art will readily think of other embodiments of the present application after considering the specification and the practice of the application disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope of the present application is pointed out by the claims.

[0091] It should be understood that the present application is not limited to the precise structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A preparation method of an N-type carbon-based field-effect transistor, characterized in that, Including: Preparing a basic carbon-based field-effect transistor with a bottom-gate structure, the bottom-gate structure including a conductive channel layer, the conductive channel layer being a carbon-based material, and the carbon-based material being at least one of graphdiyne, graphene nanoribbons, and carbon nanotubes having semiconductor characteristics; Performing a cleaning treatment on the basic carbon-based field-effect transistor using a first solution, and performing a heating treatment on the basic carbon-based field-effect transistor after the cleaning treatment to remove impurities and groups of the basic carbon-based field-effect transistor; Immersing the basic carbon-based field-effect transistor in a second solution to form a molecular film on the surface of the conductive channel layer; Performing a drying treatment on the basic carbon-based field-effect transistor after immersion to obtain an N-type carbon-based field-effect transistor; The immersing the basic carbon-based field-effect transistor in the second solution includes: Preparing a second solution, where the organic solution in the second solution is at least one of acridine orange, methylene blue, rhodamine derivatives, and cyanine derivatives containing an electron donor group; Placing the basic carbon-based field-effect transistor in the second solution, and taking it out after soaking for a second preset time, where the second preset time is greater than or equal to 5 seconds.

2. The preparation method of the N-type carbon-based field-effect transistor according to claim 1, characterized in that The preparing the basic carbon-based field-effect transistor with a bottom-gate structure includes: Providing a substrate layer, the substrate layer being a doped silicon wafer with a silicon dioxide layer covering its surface; Integrating a carbon-based material on the surface of the silicon dioxide layer to form the conductive channel layer; Preparing a source electrode and a drain electrode on the carbon-based material using a micro-nano processing technology.

3. The preparation method of the N-type carbon-based field effect transistor according to claim 1, characterized in that, The performing a cleaning treatment on the basic carbon-based field-effect transistor using a first solution, and performing a heating treatment on the basic carbon-based field-effect transistor after the cleaning treatment includes: Preparing a first solution, where the organic solution in the first solution is at least one of N-methylpyrrolidone, tetrahydrofuran, chloroform, dichloromethane, methanol, ethanol, and toluene; Placing the basic carbon-based field-effect transistor in the first solution, and taking it out after soaking for a first preset time; Performing a heating treatment on the basic carbon-based field-effect transistor after immersion to remove impurities and groups on the surface of the carbon-based material, and the groups include at least one of hydroxyl, carboxyl, amino, and methyl groups.

4. The manufacturing method of the N-type carbon-based field effect transistor according to claim 3, characterized in that The first preset time is from 1 minute to 5 minutes, and the temperature of the first solution is within a first temperature range, and the first temperature range is from 50 degrees Celsius to 80 degrees Celsius.

5. The manufacturing method of the N-type carbon-based field effect transistor according to claim 3, characterized in that, Before the performing a heating treatment on the basic carbon-based field-effect transistor after immersion, it further includes: Sequentially immersing the basic carbon-based field-effect transistor in a third solution and a fourth solution, the third solution being an acetone solution, and the fourth solution being deionized water.

6. The preparation method of the N-type carbon-based field-effect transistor according to claim 3, characterized in that, The performing a heating treatment on the basic carbon-based field-effect transistor after immersion includes: Providing an annealing furnace, the inside of the annealing furnace being vacuum or an inert gas, and the inert gas being at least one of nitrogen and argon; Placing the basic carbon-based field-effect transistor in the annealing furnace for heating, and the temperature of the annealing furnace is within a second temperature range, and the second temperature range is from 150 degrees Celsius to 550 degrees Celsius.

7. The preparation method of the N-type carbon-based field-effect transistor according to claim 1, characterized in that, Performing a drying process on the soaked basic carbon-based field-effect transistor includes: Using a clean gas to purge the surface of the basic carbon-based field-effect transistor to remove the residual second solution on the surface of the basic carbon-based field-effect transistor, and the clean gas is at least one of oxygen, nitrogen, and argon.

8. An N-type carbon-based field-effect transistor, characterized in that, Prepared by the preparation method of the N-type carbon-based field-effect transistor according to any one of claims 1 to 7, and the N-type carbon-based field-effect transistor includes: A substrate layer (1), and the substrate layer (1) is a doped silicon wafer (11) with a silicon dioxide layer (12) covering its surface; A conductive channel layer (2), and the conductive channel layer (2) is disposed above the silicon dioxide layer (12), and the conductive channel layer (2) is a carbon-based material, and the carbon-based material is at least one of graphdiyne, graphene nanoribbon, and carbon nanotube having semiconductor characteristics; An electrode (3), and the electrode (3) is disposed on the conductive channel layer (2); A molecular thin film (4), and the molecular thin film (4) covers a first region of the conductive channel layer (2), and the first region is the region on the surface of the conductive channel layer (2) except the electrode (3), and the molecular thin film (4) includes organic molecules.

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