Field-effect transistor including a transition metal dichalcogenide covered by a protective film and method for manufacturing the same

Abstract

To provide a field effect transistor including a protective film, and method of manufacturing the same.SOLUTION: There is provided a field effect transistor 100 including a protective film provided on a substrate and including hydrocarbon (HC) including a transition metal dichalcogenide thin film. Therein: a transition metal dichalcogenide capped with an HC protective film 140 is included as a channel layer 120, and a dielectric thin film 112 having a large area of a centimeter scale is formed as a protective film on a surface of the transition metal dichalcogenide. Thus, reduction in electrical performance of the field effect transistor due to scattering or trapping of carriers within the channel by adsorbing impurity molecules such as oxygen, moisture, and the like existing in a surrounding environment on the surface of the transition metal dichalcogenide and acting as defects, can be complemented, and stability of long-term storage can be improved.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a field effect transistor, and more particularly to a field effect transistor including a transition metal dichalcogenide covered with a protective film, and a method for manufacturing the same. [Background technology]

[0002] Two-dimensional (2D) semiconductor materials, including transition metal dichalcogenides (TMDs), have been studied as key elements for use as channel layers in electronic devices due to their excellent on / off current ratio and outstanding carrier mobility. However, when the surface of a transition metal dichalcogenide material is exposed to various external environments, such as the atmosphere and during device fabrication processes, various types of molecules can adsorb onto the surface. These molecules act as scattering or trapping centers, causing localized and uneven electron distribution within the channel, resulting in reduced carrier mobility and hysteresis between forward and reverse bias, which can reduce the reliability of semiconductor devices. Therefore, a protective film is needed on the surface of transition metal dichalcogenides to prevent defects caused by the adsorption of impurity molecules and provide a shielding effect to maintain electrical performance. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention has been devised to solve the above-mentioned problems, and its object is to provide a field effect transistor having a protective film and a method for manufacturing the same. [Means for solving the problem]

[0004] In order to achieve the above technical objectives, a field effect transistor according to a preferred embodiment of the present invention may include a channel layer provided on a substrate and including a transition metal dichalcogenide thin film; a plurality of electrodes arranged spaced apart from one another on a portion of the channel layer; and a protective film containing a hydrocarbon, the protective film being covered by the channel layer or the channel layer and the electrodes, and being in contact with the transition metal dichalcogenide thin film to form a van der Waals gap.

[0005] The hydrocarbon is amorphous and has a peak at 1350 cm in Raman spectroscopy. -1 Peak (D) and / or 1600 cm -1 It may partially contain a crystalline carbon structure indicated by peak (G).

[0006] The dielectric constant of the protective film may be 10-40.

[0007] The protective film may have a thickness of 0.1 to 5 nm.

[0008] The van der Waals gap may be 1 to 5 Å.

[0009] The protective film is characterized by maintaining the electrical performance of the field-effect transistor even when exposed to an external environment, and maintaining the electrical performance of the field-effect transistor may be measured as a decrease in electron mobility of less than 10% when exposed to air and oxygen for several months.

[0010] In order to achieve the above technical object, a method for manufacturing a field effect transistor according to a preferred embodiment of the present invention may include the steps of: growing a hydrocarbon thin film on a substrate (S01); preparing a field effect transistor including a channel layer having a transition metal dichalcogenide thin film and a plurality of electrodes spaced apart from one another on a remaining portion of the channel layer (S02); and transferring the hydrocarbon thin film to cover the transition metal dichalcogenide thin film and the electrodes, so that the hydrocarbon thin film and the transition metal dichalcogenide thin film form a van der Waals gap (S03).

[0011] The step of growing the hydrocarbon thin film may include low temperature chemical vapor deposition (LTCVD), inductively coupled plasma chemical vapor deposition (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MoCVD), plasma-enhanced chemical vapor deposition (PECVD), or two or more methods selected from these.

[0012] The growth temperature in the step of growing the hydrocarbon thin film may be in the range of 500K to 900K.

[0013] The hydrocarbon thin film may have a dielectric constant of 10-40.

[0014] The hydrocarbon is amorphous and has a peak at 1350 cm in Raman spectroscopy. -1 Peak (D) and / or 1600 cm -1 It may partially contain a crystalline carbon structure indicated by peak (G).

[0015] The hydrocarbon thin film may have a thickness of 0.1 to 5 nm.

[0016] The van der Waals gap may be 1 to 5 Å.

[0017] The hydrocarbon thin film is characterized by maintaining the electrical performance of a field-effect transistor even when exposed to an external environment, and maintaining the electrical performance of the field-effect transistor may be measured as a decrease in electron mobility of less than 10% when exposed to air and oxygen for several months. [Effects of the Invention]

[0018] According to the present invention as described above, a field effect transistor (FET) having a transition metal dichalcogenide capped with a hydrocarbon (HC) protective film according to a preferred embodiment of the present invention as a channel layer can improve storage stability over long periods by forming a dielectric thin film having a large centimeter-scale area on the surface of the transition metal dichalcogenide as a protective film, thereby solving the problem of impurity molecules such as oxygen and moisture present in the surrounding environment adsorbing on the surface of the transition metal dichalcogenide and acting as defects, which cause carrier scattering or capture in the channel and result in a decrease in the electrical performance of the field effect transistor.

[0019] The effects of the present invention are not limited to the effects described above, but also include other effects that are not explicitly mentioned, although they would be clearly understood by a person skilled in the art from the overall description of the specification. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a schematic diagram showing a cross section of a field-effect transistor according to one embodiment of the present invention. [Figure 2] 1 is a flowchart illustrating a method for manufacturing a field effect transistor according to an embodiment of the present invention. [Figure 3] 1A and 1B are (a) scanning electron microscope and (b) high-resolution transmission electron microscope images of a cross section of a multilayer MoSe2 capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention. [Figure 4] 1 is an optical microscope photograph of a hydrocarbon (HC) film according to Production Example 1 of the present invention. [Figure 5] 1 shows the results of Raman spectroscopy of a hydrocarbon (HC) film according to Production Example 1 of the present invention. [Figure 6] FIG. 1 shows (a) the results of atomic force microscopy (AFM) of the hydrocarbon (HC) film according to Production Example 1 of the present invention, (b) the results of high-magnification atomic force microscopy (AFM), and the results of surface height scanning along the red solid line. [Figure 7a] 1 shows the structure of a metal-insulator-semiconductor (MIS) element for measuring the dielectric constant of a hydrocarbon (HC) film according to Preparation Example 1 of the present invention. [Figure 7b] 1 is an optical microscope photograph of an MIS element of a hydrocarbon (HC) film according to Production Example 1 of the present invention. [Figure 7c] 1 shows the results of CV (Capacitance-voltage) characteristics of a hydrocarbon (HC) film according to Preparation Example 1 of the present invention. [Figure 7d] 1 shows the results of two-terminal IV characteristics of a hydrocarbon (HC) film according to Production Example 1 of the present invention. [Figure 8] 1 is an optical microscope photograph of a plurality of field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention formed on a 2x2 cm substrate. [Figure 9a] 1 shows the results of transmission characteristics of field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention, depending on whether or not a HC protective film is present. [Figure 9b]1 shows the results of output characteristics of field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention, compared to Comparative Example 1 without a HC protective film. [Figure 9c] 1 shows the results of output characteristics of field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention and Comparative Example 1. [Figure 9d] 1 shows statistical results of electron mobility according to the presence or absence of a hydrocarbon (HC) protective layer for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective layer according to Example 1 and Comparative Example 1 of the present invention. [Figure 9e] 1 shows statistical results of Vth hysteresis depending on the presence or absence of a hydrocarbon (HC) protective film for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention. [Figure 10a] 1 is a schematic diagram of a stacked HC / MoSe2 structure in relation to a field effect transistor having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention. [Figure 10b] 1 shows the projected density of states (PDoS) results for MoSe2 (top) and HC (bottom) in relation to field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective layer according to Example 1 and Comparative Example 1 of the present invention. [Figure 10c] 1 shows band structure calculation results for field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention. [Figure 10d]1 shows the results of differential charge density (red: electron accumulation, green: electron depletion) for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention and Comparative Example 1. [Figure 10e] 1 shows the results of the planar average charge density difference (positive value: electron accumulation, negative value: electron depletion) for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention and Comparative Example 1. [Figure 10f] 1 shows the results of calculating electrostatic potentials in relation to field effect transistors having a multi-layer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention. [Figure 11a] 1 shows the results of Raman spectroscopy after storage for three months for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention. [Figure 11b] 1 shows the results of output characteristics of field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention, compared to Comparative Example 1 without a HC protective film. [Figure 11c] 1 shows the results of output characteristics of field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention. [Figure 11d] 1 shows statistical results of electron mobility according to the presence or absence of a protective layer for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective layer according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention. [Figure 11e]1 shows statistical results of Vth hysteresis depending on the presence or absence of a hydrocarbon (HC) protective film for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Advantages and features of the present invention, as well as methods for achieving them, will become more apparent with reference to the following detailed description of the embodiments in conjunction with the accompanying drawings. However, the technical idea of ​​the present invention is not limited to the embodiments disclosed below, and can be embodied in various different forms. These embodiments are provided merely to complete the disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art. The present invention is defined only by the scope of the claims. Furthermore, the same reference numerals refer to the same components throughout the specification.

[0022] Furthermore, unless otherwise specified herein or clearly contradictory to the context, all terms used in this specification, including technical and scientific terms, should be used in a manner commonly understood by those of ordinary skill in the art to which this invention pertains. Furthermore, commonly used terms, such as those defined in dictionaries, should not be construed as ideal or overly formal unless expressly defined in this disclosure. The terms used in this specification are merely used to describe the embodiments and are not intended to limit the present invention. In this specification, singular expressions include plural terms unless the context clearly dictates otherwise.

[0023] As used herein, terms such as "comprises" and / or "comprising" do not exclude the presence or addition of stated components, steps, operations and / or elements.

[0024] Field-effect transistor with a transition metal dichalcogenide channel layer covered with a hydrocarbon passivation film

[0025] FIG. 1 is a schematic diagram showing a cross section of a field effect transistor according to one embodiment of the present invention.

[0026] 1, a field effect transistor according to an embodiment of the present invention includes a channel layer 120, a plurality of electrodes 130, and a protective film 140. More specifically, the channel layer 120 is provided on a substrate 110 and includes a transition metal dichalcogenide thin film, the electrodes 130 are disposed on portions of the channel layer 120 so as to be spaced apart from each other, and the protective film 140 is covered by the channel layer 120 or the channel layer 120 and the electrodes 130, and is in contact with the transition metal dichalcogenide thin film to form a van der Waals gap and includes a hydrocarbon.

[0027] The substrate 110 can be a semiconductor substrate made of a semiconductor material such as silicon or silicon-on-insulator (SoI). Specifically, a silicon 111 substrate with a dielectric layer 112 of several to several hundred nanometers thick, such as silicon oxide, formed on its surface can be used. It is also possible to use a wide bandgap semiconductor substrate made of silicon carbide (SiC), gallium nitride (GaN), gallium oxide (Ga2O3), or the like. The substrate 110 can also be doped with a dopant.

[0028] The channel layer 120, which responds by generating an electrical change when an electrical signal is applied, may include a two-dimensional semiconductor material. Specifically, the two-dimensional (2D) semiconductor material may have a structure in which strong covalent bonds are formed within a single layer and relatively weak van der Waals forces are used to bond layers. The two-dimensional semiconductor material may be included in the channel layer 120 as an ultrathin film or ultrathin plate-like particles, e.g., flakes, having a layered structure. Alternatively, the two-dimensional semiconductor material may be included as a layered material in the form of a monolayer or multilayers (two or more layers). Specifically, the two-dimensional semiconductor material may be included as a multilayer structure with several layers. The two-dimensional semiconductor material exhibits indirect transition characteristics in a bulk or thin film state with a normal thickness, but direct transition characteristics when the film is a single layer or a few layers thick. It also has excellent photoresponsiveness, transparency, and flexibility, making it suitable for use in optoelectronic devices.

[0029] In addition, the two-dimensional semiconductor material has a layered structure in which each layer has very strong covalent bonds between the constituent atoms, and the layers are bound together by weak van der Waals forces. Since there are no dangling bonds extending outside the layers, in principle, there is only two-dimensional interaction with the constituent atoms, and carrier transport exhibits elastic transport, unlike conventional thin films or bulk materials. This makes it applicable as a high-mobility, high-speed, low-power semiconductor.

[0030] The two-dimensional semiconductor material may include a transition metal dichalcogenide (TMD). Specifically, the transition metal dichalcogenide material may be represented by the general formula MX2, where M is a transition metal element, such as Mo, W, Nb, V, Ta, Ti, Zr, Hf, Tc, Re, Ru, Co, Pd, Pt, Cu, Ga, In, Sn, Ge, Pb, or a combination thereof, and X is a chalcogen element, such as S, Se, Te, or a combination thereof. Specifically, the transition metal dichalcogenide material may include at least one selected from MoS2, MoSe2, MoTe2, WS2, WSe2, WTe2, ZrS2, ZrSe2, HfS2, HfSe2, NbSe2, ReSe2, PdTe2, or a combination thereof. More specifically, the transition metal dichalcogenide material may include MoS2, MoSe2, WS2, WSe2, or at least one selected from these, and in one embodiment, may include MoSe2, but is not limited thereto.

[0031] The crystal structure of the transition metal dichalcogenide material may have a hexagonal structure in the planar direction based on a covalent bond between the transition metal M and the chalcogen element X. The crystal structure can be modified through further phase change or doping steps.

[0032] In particular, the transition metal dichalcogenide may be contained in the form of an ultrathin film or ultrathin plate-like particles having a layered structure, for example, in the form of flakes, and may be contained as a single layer (monolayer) or a multilayer (multilayer) of two or more layers. When the transition metal dichalcogenide material is contained in the form of flakes, those having an average diameter on the scale of several nanometers to several micrometers (μm) can be used. For example, the average diameter of the flakes may be 1 nm to 100 μm.

[0033] The electrode 130 may include a metal or a metal compound. The metal or metal compound may include at least one metal element selected from the group consisting of Ti, Ni, Au, Ag, and combinations thereof, and may be any metal or metal compound suitable for use in electronic devices such as metal electrodes and metal interconnections.

[0034] The protective film 140 may be a passivation film that covers the transition metal dichalcogenide thin film to prevent various problems that may arise when the transition metal dichalcogenide thin film is exposed to external environments. When the surface of a transition metal dichalcogenide material is exposed to various external environments, such as the atmospheric environment or the manufacturing process of a field-effect transistor, various types of molecules on the surface may adsorb. These molecules act as scattering or capture centers, causing localized and uneven distribution of electrons in the channel, resulting in reduced carrier mobility and hysteresis between forward and reverse biases, thereby reducing the performance of the field-effect transistor. Therefore, a protective film 140 may be provided on the surface of the transition metal dichalcogenide to prevent defects caused by the adsorption of impurity molecules, such as oxygen and moisture, and to provide a shielding effect to maintain electrical performance.

[0035] The protective film 140 covers the surface of the channel layer 120 and can play a role in maintaining the electrical performance of the field effect transistor even when exposed to the external environment.

[0036] The protective film 140 may contain hydrocarbon (HC). The hydrocarbon (HC) refers to a compound whose main skeleton is a bond between carbon atoms and hydrogen atoms, and 3 Bond or sp 2 Amorphous materials containing random bonds, specifically sp 3 Bond or sp 2 It can refer to a chemical structure that is not composed only of bonds, and can refer to a structure that contains a certain proportion of so-called dangling bonds, which mean fixed free radicals. 3 Bond or sp 2 For example, in one embodiment of the present invention, Raman spectroscopy shows a peak at 1350 cm, which indicates crystalline carbon. -1 Peak (D) and / or 1600 cm -1 The hydrocarbon (HC) film may partially contain a crystalline carbon structure indicated by peak (G). Such a hydrocarbon (HC) film is an amorphous material and may have characteristics such as a dielectric constant at a certain level or higher compared to hydrocarbon materials with a crystalline structure, such as graphene and diamond. In addition, the hydrocarbon (HC) film used in the present invention is an amorphous material, and unlike crystalline materials, is very easy to perform large-area growth and transfer processes.

[0037] The hydrocarbon (HC) may have a dielectric constant of 10 to 40, specifically 15 to 35, and more specifically 20 to 30. A hydrocarbon (HC) having a dielectric constant within this range may be suitable for use in gate control using a high dielectric constant (high K). Furthermore, the hydrocarbon (HC) may be doped or modified using a further chemical treatment to impart desired dielectric properties. In one embodiment, the hydrocarbon (HC) may have a dielectric constant of 26, but is not limited thereto.

[0038] Furthermore, the hydrocarbon (HC) can maintain the electrical performance of a field-effect transistor (FET) even when exposed to an external environment. Maintaining the electrical performance of the field-effect transistor (FET) may mean that the electron mobility of the field-effect transistor decreases only slightly when exposed to air and oxygen for several months. The electron mobility of the field-effect transistor may decrease by less than 10%, specifically less than 8%, and more specifically less than 6%. In one embodiment, the electron mobility decrease may be 5.5%, but is not limited thereto.

[0039] Furthermore, maintaining the electrical performance of the field effect transistor (FET) can mean that the FET exhibits a small hysteresis increase when exposed to air and oxygen for several months. th Less than, more specifically 7V th In one embodiment, the hysteresis gain of the field effect transistor may be measured as less than 5V. th However, it is not limited to this.

[0040] Furthermore, the hydrocarbon (HC) can provide a property of improving the electron mobility of a field-effect transistor by 30 to 80% when in contact with the transition metal dichalcogenide thin film. In one embodiment, the electron mobility (μ) of the transition metal dichalcogenide thin film without a protective film is approximately 20 to 30 cm 2 V -1 s -1 However, the electron mobility (μ) of the transition metal dichalcogenide thin film with the hydrocarbon (HC) protective film is 40 to 50 cm 2 V -1 s -1 However, it is not limited to this level.

[0041] In addition, the hydrocarbon (HC) can provide the transition metal dichalcogenide thin film with the property of reducing hysteresis during sweeping between forward and reverse biases. In one embodiment, the hysteresis of the transition metal dichalcogenide thin film without a protective film is approximately 20 to 30 V. th Although the hysteresis of the transition metal dichalcogenide thin film with the hydrocarbon (HC) protective film is high, the hysteresis is 10 to 15 V. th It may be possible to reduce the level of

[0042] Meanwhile, the channel layer with the hydrocarbon (HC) protective film can exhibit characteristics of maintaining electrical characteristics, as measured by a decrease in electron mobility of less than 10% when exposed to air and oxygen for several months. In one embodiment, the field effect transistor having the channel layer with the hydrocarbon (HC) protective film has a thickness of about 35 to 40 cm 2 V -1 s -1 and electron mobility of about 10 to 20V th The hysteresis increase was 35-40cm even after 3 months. 2 V -1 s -1 and the hysteresis increase width can be maintained.

[0043] In addition, the hydrocarbon (HC) may have other physical properties such as moisture permeability, low oxygen permeability, and chemical resistance so as to maintain the electrical performance of the field effect transistor even when exposed to the external environment.

[0044] The hydrocarbon (HC) may be contained in the form of a thin film, and such a hydrocarbon (HC) thin film may have a soft and continuous surface feature at the bottom without pinholes, and may have a horizontal or vertical length of several to several tens of centimeters. The thickness of the hydrocarbon (HC) thin film may be several nanometers, 1 to 5 nm, specifically 2 to 3 nm, but is not limited thereto.

[0045] The hydrocarbon (HC) thin film may be grown by a chemical vapor deposition (CVD) method, such as low-temperature chemical vapor deposition (LTCVD), inductively coupled plasma chemical vapor deposition (ICP-CVD), low-pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MoCVD), plasma-enhanced chemical vapor deposition (PECVD), or two or more methods selected from the above. In one embodiment, the hydrocarbon (HC) thin film may be grown using inductively coupled plasma chemical vapor deposition (ICP-CVD), but is not limited thereto.

[0046] The hydrocarbon (HC) thin film may have a sufficiently large area and may be formed as a protective film covering the channel layer 120 or both the channel layer 120 and the electrode 130. In this case, the hydrocarbon (HC) thin film may act as a passivation that provides a shielding effect by blocking material exchange with the external environment to prevent molecules such as oxygen and moisture from being adsorbed on the surface of the channel layer 120 of the field effect transistor, thereby preventing the electrical performance of the field effect transistor from being reduced.

[0047] In this case, during the process of forming the hydrocarbon (HC) thin film as a protective film, it may come into close contact with the channel layer 120 and the electrode 130. To promote this contact process, a further low-temperature heat treatment, for example, a low-temperature heat treatment at a temperature of 80 to 120°C, may be added.

[0048] The hydrocarbon (HC) thin film is positioned to contact the channel layer 120 and a two-dimensional semiconductor material, such as a transition metal dichalcogenide thin film, to form a van der Waals gap at the interface between them. The van der Waals gap may be 1 nm or less, i.e., a few angstroms (Å). The van der Waals gap may be 1 to 5 Å, and in one embodiment, 3 Å, but is not limited thereto.

[0049] Method for manufacturing a field-effect transistor having a transition metal dichalcogenide channel layer covered with a hydrocarbon protective film

[0050] FIG. 2 is a flowchart showing a method for manufacturing a field effect transistor according to one embodiment of the present invention.

[0051] Referring to FIG. 2, a method for manufacturing a field effect transistor having a transition metal dichalcogenide channel layer covered with a hydrocarbon protective film according to one embodiment of the present invention may first include a step (S01) of growing a hydrocarbon thin film on a substrate.

[0052] The step of growing the hydrocarbon thin film can be performed using, for example, low-temperature chemical vapor deposition (LTCVD), inductively coupled plasma chemical vapor deposition (ICP-CVD), low-pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MoCVD), plasma-enhanced chemical vapor deposition (PECVD), or two or more methods selected from these. In one embodiment, the step of growing the hydrocarbon thin film can be performed using inductively coupled plasma chemical vapor deposition (ICP-CVD), but is not limited thereto.

[0053] In order to grow the hydrocarbon thin film on a substrate, the substrate may be a silicon substrate having a dielectric layer with a thickness of several to several hundred nanometers formed on its surface, such as silicon oxide.

[0054] A metal catalyst layer can be formed on the substrate as a catalyst for hydrocarbon growth. The metal catalyst layer can be a thin metal film deposited to a thickness of several to several hundred nanometers, or a thin film in which nano-sized metal catalyst particles are uniformly dispersed. The metal catalyst can be, for example, at least one selected from the group consisting of Au, Ag, Cu, Pt, Zn, Fe, Ti, Sn, In, Bi, and Ni. In one embodiment, the metal catalyst can be Ag, and the thickness of the metal catalyst layer can be 150 to 250 nm, but is not limited thereto.

[0055] Thereafter, the substrate on which the metal catalyst layer is formed may be placed in a chamber, and a hydrocarbon gas and a carrier gas may be injected into the chamber, followed by heating to a temperature at which the hydrocarbons grow.

[0056] As the hydrocarbon gas, a hydrocarbon substance containing C1 to C3 carbon and hydrogen, such as methane, ethane, or propane, can be used, and in one embodiment, methane (CH4) can be used as the hydrocarbon gas.

[0057] The growth temperature of the hydrocarbon may be in the range of 500 K to 900 K. The hydrocarbon grown at a growth temperature within the range is amorphous, and has a peak at 1350 cm in Raman spectroscopy. -1 Peak (D) and / or 1600 cm -1 A hydrocarbon material having a structure partially containing a crystalline carbon structure indicated by peak (G) and exhibiting a dielectric constant of about 26 may be produced. The chemical structure of the hydrocarbon grown at a growth temperature below this range is composed solely of amorphous material, making it difficult to accurately determine this carbon structure. However, if a growth temperature above this range is applied, a material having a crystalline carbon structure with high crystallinity may be produced, making it difficult to produce a hydrocarbon thin film with the desired properties. Specifically, the growth temperature of the hydrocarbon may be 600K to 800K, more specifically 650K to 750K. In one embodiment, the growth temperature of the hydrocarbon may be 737K, but is not limited thereto.

[0058] The hydrocarbon thin film grown by the above method can grow to a large area corresponding to the size of the substrate, for example, several to several tens of square centimeters (cm 2 ) can be formed in an area of ​​the scale.

[0059] A polymer solution may be applied to the surface of the hydrocarbon thin film grown on the substrate and compacted to form a polymer coating, for example, a polymethyl methacrylate (PMMA) coating, which may then be separated from the substrate to form a polymer coating with a hydrocarbon thin film. The hydrocarbon thin film may then be transferred to a field effect transistor (described later) to form a protective film.

[0060] Thereafter, the method may include a step (S02) of preparing a field effect transistor including a channel layer including a transition metal dichalcogenide thin film and a plurality of electrodes arranged spaced apart from each other on a remaining portion of the channel layer.

[0061] The steps of preparing the transition metal dichalcogenide thin film and the electrodes can be similar to those described in the section on the field effect transistor having a transition metal dichalcogenide channel layer covered with a hydrocarbon protective film, and a detailed description thereof will be omitted for the sake of brevity.

[0062] Specifically, the transition metal dichalcogenide thin film can be formed by a mechanical method such as mechanically peeling it off from a layered bulk material using an adhesive material, or by a chemical method such as molecular beam epitaxy, which grows a crystal from a seed that has been successfully grown under high or ultra-high vacuum conditions by an epitaxial growth method for depositing a single crystal thin film, or a molten salt assisted thermal chemical vapor deposition method. However, the above-mentioned method is merely an example, and any known non-limiting method can be used to form a transition metal dichalcogenide layer.

[0063] The electrode may include a metal or a metal compound. The metal or metal compound may include at least one metal element selected from the group consisting of Ti, Ni, Au, Ag, and combinations thereof, and may be any metal or metal compound suitable for use in electronic devices such as metal electrodes and metal interconnections.

[0064] The step of depositing the electrode may be performed using, but is not limited to, a metal thin film deposition method that applies energy at a level that does not induce defects in the channel layer, such as an electron beam deposition apparatus, a thermal deposition apparatus, or sputtering.

[0065] Thereafter, the method may include a step (S03) of transferring the hydrocarbon thin film to cover the transition metal dichalcogenide thin film and the electrode, so that the hydrocarbon thin film and the transition metal dichalcogenide thin film form a van der Waals gap.

[0066] The polymer coating having the hydrocarbon thin film formed thereon can be positioned so that the portion where the hydrocarbon is formed and the portion where the transition metal dichalcogenide thin film is positioned are joined together. Then, the polymer / hydrocarbon / transition metal dichalcogenide thin film is subjected to a low-temperature heat treatment, for example, a heat treatment at a temperature of 80 to 120°C, to flatten the polymer coating and strengthen the contact strength between the hydrocarbon thin film and the transition metal dichalcogenide thin film.

[0067] A van der Waals gap may be formed at the interface where the hydrocarbon thin film and the transition metal dichalcogenide thin film come into contact. In other words, the hydrocarbon thin film and the transition metal dichalcogenide thin film may be bonded by van der Waals forces (vdW) through direct contact. The formation of the van der Waals gap removes dangling bonds with high surface reactivity, preserving the inherent physical properties of the channel layer and forming a quasi-ideal interface that blocks carrier leakage within the channel layer. This improves carrier mobility within the channel layer including the transition metal dichalcogenide thin film and reduces hysteresis loops in field-effect transistors.

[0068] The van der Waals gap may be 1 nm or less, i.e., a few angstroms in size. The van der Waals gap may be 1 to 5 Å, and in one embodiment, may be 3 Å, but is not limited thereto.

[0069] The present invention will be described in more detail below with reference to examples and comparative examples. However, the following examples and comparative examples are for illustrative purposes only and do not limit the scope of the present invention.

[0070] Production Example 1: Production of hydrocarbons (HC) by ICP-CVD method To form a hydrocarbon (HC) thin film using inductively coupled plasma chemical vapor deposition (ICP-CVD), a SiO2 / Si substrate with a 200 nm thick Ag layer deposited as a catalyst for hydrocarbon (HC) growth was placed in a chamber. 20 sccm of CH4 gas and 100 sccm of a 90:10 vol% Ar+H2 mixture were injected, and the chamber temperature was raised to the hydrocarbon (HC) growth temperature (737 K). Then, an inductively coupled plasma (ICP) was introduced under conditions of a power of 600 W and a chamber pressure of 1 Torr while injecting 20 sccm of CH4 gas. A hydrocarbon (HC) film was then grown using the ICP-CVD method.

[0071] Manufacturing Example 2: Manufacturing of multilayer MoSe2 field effect transistor (FET) To fabricate multilayer MoSe field-effect transistors (FETs), multilayer MoSe flakes were first prepared by mechanically peeling them from bulk MoSe using Scotch tape. These were then transferred onto a p-Si substrate (2 cm x 2 cm) with a 300 nm-thick SiO dielectric layer. To remove any chemicals remaining from the multilayer MoSe flake transfer process, the substrate was immersed in acetone for 2 hours, rinsed with isopropyl alcohol, and dried. For source and drain electrodes, 20 nm-thick Ti and 200 nm-thick Ni were deposited using electron beam evaporation, and the electrodes were patterned using photolithography and wet etching. After this, the substrate was annealed at 200 °C for 2 hours in an Ar+H mixed gas atmosphere to remove organic residues and reduce the contact resistance between the metal electrode and the channel layer of MoSe. Tens to hundreds of multilayer MoSe field-effect transistors (FETs) were fabricated on the 2 cm x 2 cm substrate.

[0072] Example 1: Fabrication of a field effect transistor (FET) using a hydrocarbon (HC) film as a protective film A PMMA (Polymethylmethacrylate) solution was applied to the surface of the hydrocarbon (HC) film prepared in Preparation Example 1, and then dried. The resulting PMMA / HC / substrate was etched in a hydrogen fluoride (HF) etching solution for approximately 3 minutes to produce a PMMA / HC coating. This was then rinsed with deionized water for 15 minutes. The PMMA / HC coating with the hydrocarbon film was then placed on top of the 2 cm x 2 cm multilayer MoSe2 FETs prepared in Preparation Example 2, covering several hundred multilayer MoSe2 FETs. The protective layer was then transferred onto the PMMA / HC / multilayer MoSe2 FETs. The PMMA / HC / multilayer MoSe2 FETs were heated on a hot plate at 373 K for one day to flatten the PMMA film and promote adhesion between the MoSe2 layer and the hydrocarbon (HC). The PMMA was then removed by rinsing with acetone. The thus-fabricated HC / multilayer MoSe2 FET was rinsed with isopropanol and dried by heating at 100°C for 15 minutes to produce a multilayer MoSe2 field effect transistor (FET) capped with a hydrocarbon (HC) protective film.

[0073] Comparative Example 1: Fabrication of a Field-Effect Transistor (FET) without a Protective Film The multilayer MoSe2 field effect transistor (FET) of Preparation Example 2 was used as it was to fabricate a field effect transistor without a protective film.

[0074] Experimental Example 1: Measurement of the physical properties of hydrocarbon protective films FIG. 4 is an optical microscope photograph of the hydrocarbon (HC) film according to Production Example 1 of the present invention, FIG. 5 is a result of Raman spectroscopy for the hydrocarbon (HC) film according to Production Example 1 of the present invention, and FIG. 6 is (a) the result of atomic force microscopy (AFM) for the hydrocarbon (HC) film according to Production Example 1 of the present invention, (b) the result of high-magnification atomic force microscopy (AFM) and the result of surface height scanning along the red solid line.

[0075] 4 to 6, the hydrocarbon (HC) protective film according to Preparation Example 1 of the present invention was fabricated as a large-area thin film measuring approximately 2 x 2 cm. It can be seen that this was fabricated by immersing PMMA / HC / MoSe2 in acetone for 24 hours to remove the PMMA. The HC film (Preparation Example 1) synthesized at 737 K exhibited two carbon peaks, i.e., at 1350 cm and 1350 cm, which indicate that the hexagonal honeycomb structure was destroyed and the film had a disordered crystallinity. -1 Peak (D) and 1600 cm -1 The HC film synthesized at 473 K showed peaks (G). In contrast, the intensity of the two peaks was not observed, suggesting an increase in the entropy of the carbon structure, i.e., no meaningful carbon structure was observed. Next, AFM images confirmed that the bottom surface of the HC film peeled from the substrate had a soft, continuous surface without pinholes. Considering that a thin film is deposited uniformly over a large area, the HC film grown according to Preparation Example 1 of the present invention had a surface roughness RMS (root mean square) of only about 2.6 nm, demonstrating uniform growth. Therefore, it can be inferred that a defect-free van der Waals gap can be formed in the HC / MoSe2 stack, leading to excellent electrical performance in field-effect transistors containing transition metal dichalcogenides.

[0076] FIG. 7 shows (a) the structure of a metal-insulator-semiconductor (MIS) element for measuring the dielectric constant of a hydrocarbon (HC) film according to Preparation Example 1 of the present invention, (b) an optical microscope photograph of the MIS element, (c) CV (Capacitance-voltage) and (d) two-terminal IV characteristics.

[0077] Referring to FIG. 7, the hydrocarbon (HC) protective film according to Preparation Example 1 of the present invention is a dielectric film, and its gate-dependent capacitance was measured using a metal-dielectric-semiconductor (MIS) device. A gate bias was applied to the backside of an N-type Si substrate, and a gold (Au) electrode with a thickness of 0.2 μm and a diameter of 100 μm was deposited on the HC dielectric layer. A maximum capacitance of approximately 3.0 nF was observed in the n-branch. The HC dielectric film exhibited low hysteresis loss (less than 10 mV), a sharp transition between cumulative modulation and depletion, and a very low trapped charge density. The hydrocarbon (HC) film according to Preparation Example 1 of the present invention (grown at a temperature of 737 K) had a dielectric constant of approximately 26, and a maximum capacitance C max was calculated according to the following equation 1: C max =ε HC / t HC …(1)

[0078] where ε HC is the permittivity of hydrocarbons (HC), and t HC is the thickness of the hydrocarbon (HC) film, and the thickness of the hydrocarbon (HC) film is about 2.4 nm, so the equivalent oxide thickness is about 0.2 nm. The leakage current of the Au / HC / Si MIS capacitor is about 1 A cm at an applied voltage of 1 V. -2 In addition, the HC dielectric film has a densitivity of at least 10 MVcm -1 The voltage was maintained at 2 V or higher, which corresponds to a dielectric strength of 1000 V.

[0079] FIG. 3 shows (a) a scanning electron microscope image and (b) a high-resolution transmission electron microscope image of a cross section of a multilayer MoSe2 capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention. FIG. 8 shows an optical microscope image of a plurality of field-effect transistors having a multilayer MoSe2 capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention as a channel layer formed on a 2 x 2 cm substrate.

[0080] 3 and 8, a hydrocarbon (HC) film (shown by the white dotted line) measuring 2x2 cm was transferred onto a MoSe2 FET fabricated on a SiO2 / Si substrate. Observation of the cross section of the stacked HC / MoSe2 FET revealed that it was uniform and continuous, with no noticeable pinholes or particulate defects. A thin HC film with a thickness of approximately 2.4 nm was coated on the multilayered MoSe2 to protect the channel layer, and the van der Waals gap was confirmed to be 0.3 nm (3 Å).

[0081] Experimental example 2: Measurement of electrical characteristics of elements FIG. 9 shows the transmission characteristics of field-effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 and Comparative Example 1 of the present invention, with and without the HC protective film, (a) the output characteristics of Comparative Example 1 without the HC protective film, (c) the output characteristics of Example 1 with the HC protective film, (d) statistics of electron mobility with and without the HC protective film, and (e) V with and without the HC protective film. th This is a statistical result of hysteresis.

[0082] Referring to Figure 9, V DSThe transfer characteristics for an applied source-drain voltage of I = 1 V show normal n-type behavior without a hydrocarbon (HC) passivation (shown in black). On the other hand, with a passivation (shown in blue), the transfer characteristics show semi-log scaled behavior, with I in the n-branch. oN The current increases from about 60 to 90 μA, while the I oFF The current was almost constant. FE-e ) was obtained by the following equation 2. JPEG0007782895000001.jpg1478…(2)

[0083] where δV DS / δV BG|max is the maximum back-gated trans conductance, L and W are the length and width of the channel, respectively, and C oX is the geometric back-gate capacitance, V DS indicates the drain-source voltage. The field-effect electron mobility (μ FE-e ) is approximately 29.61 cm 2 V -1 s -1 The field-effect electron mobility (μ FE-e ) is approximately 41.18cm 2 V -1 s -1 It can be seen that the provision of the protective film improves the mobility of field-effect electrons by about 40%.

[0084] In addition to the improved carrier transport behavior in the HC / MoSe2 van der Waals junction, the hysteresis between forward and reverse bias sweeps is significantly reduced, further improving the drive performance. To extract a quantified value of the hysteresis loss, the threshold voltage (V) of the forward and reverse sweep curves was extrapolated from the linear scale using the linear region method (ELR). th ) was extracted. The ELR is calculated by dividing the maximum initial gradient (maximum tipping point, gm) by the I D -V g The gate voltage axis intercept of the linear extrapolation of the graph (I D Therefore, with the HC capping layer on the MoSe2 FET, the hysteresis was reduced from 25 V to 12 V due to the formation of a van der Waals interface. th The negative shift of V from about 4 to 10 V indicates slight n-doping. The forward sweep (from negative to positive) shows a further negative bias shift in the threshold voltage (V TH-FW ) migration, indicating electron trapping in the MoSe2 channel. Conversely, a reverse sweep (from positive to negative) involves a shift in the critical voltage toward more positive bias, indicating de-trapping of the trapped electrons. The hysteresis of transition metal dichalcogenide FETs can be modified by the range of the gate bias sweep, the quality of the transition metal dichalcogenide / hydrocarbon (HC) interface, and the thickness of the gate dielectric.

[0085] Improved electric drive performance with a sweep speed of 1.6Vs -1 As shown in Fig. 9b, the I of the MoSe2 FET (Comparative Example 1) without a protective film D is V DS The output performance of the MoSe2 FET (Example 1) with a hydrocarbon (HC) protective film in Figure 9c is close to ohmic operation, and I D and V DS The linear relationship between V and V is maintained.BG = 40V, then 10V DS Output current (I oN ) increased from 422 to 592 μA, and -10 V DS Output current (I oN ) improves from 536 to 718 μA. In contrast, when a low-temperature grown (473 K) hydrocarbon (HC) protective film is used, the hysteresis loss increases significantly. Therefore, the HC / MoSe2 FET with a van der Waals interface according to the present invention passivates (protects) the channel surface and effectively blocks molecular adsorption on the MoSe2 surface, thereby reducing the hysteresis and improving electron mobility of the device. The van der Waals gap (approximately 0.3 nm) exists at the interface between the HC protective film and MoSe2, fundamentally suppressing the occurrence of atomic disorder and interface defects.

[0086] 9d and 9e, a reproducibility analysis was performed using five identical devices, and it was found that the MoSe2 FET with a hydrocarbon (HC) protective film (Example 1, shown as HC / MoSe2) increased the electron mobility by about 9 to 57% compared to a normal MoSe2 FET without a protective film (Comparative Example 1, shown as Bare MoSe2). In addition, in the case of Example 1, the reproducibility of the hysteresis reduction was about 10 to 17 V. th In contrast, the hysteresis of Comparative Example 1 was found to be within the range of about 16 to 37 V. th It is distributed in the range of.

[0087] FIG. 10 shows field-effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Example 1 of the present invention and Comparative Example 1. (a) Schematic diagram of the stacked HC / MoSe2 structure, (b) Projected density of states (PDoS) of MoSe2 (top) and HC (bottom), (c) Band structure calculation, (d) Differential charge density (red: electron accumulation, green: electron depletion), (e) Planar average charge density difference (positive value: electron accumulation, negative value: electron depletion), and (f) Calculation results of electrostatic potential.

[0088] Referring to Figure 10, density functional theory (DFT) calculations can be used to predict the electrical effect of the formation of a van der Waals gap using a hydrocarbon (HC) protective layer on monolayer MoSe2. In this study, 3x3 and 4x4 supercells were used for the monolayer MoSe2 and HC models, respectively. As shown in Figure 10a, the atomic structure of amorphous hydrocarbon (HC) can be calculated by replacing C atoms with H atoms in the honeycomb lattice of the carbon network, since it is nearly impossible to accurately estimate the amorphous structure. The van der Waals gap between HC and MoSe2 was calculated to be 4.37 Å, which is within a similar range to the TEM results shown in Figure 3b. The range within the blue dotted box in Figure 10b indicates the range of the MoSe2 band gap. Comparing the projected density of states (PDoS) of MoSe2 (top) and HC (bottom) confirms that there are no observable electronic states within the MoSe2 band gap. As is clear from Figure 10c, the band structure of MoSe2 with a hydrocarbon (HC) protective film (Example 1) is substantially identical to the band structure of MoSe2 without a protective film (Comparative Example 1).

[0089] Figure 10d shows the charge density difference for the HC / MoSe2 structure. Red corresponds to charge accumulation, while green corresponds to charge depletion. The difference in charge density indicates hydrocarbon (HC) stacking on the MoSe2 surface, inducing charge redistribution near the van der Waals interface region. In contrast, Figure 10e shows that only a small charge concentration in MoSe2 has shifted toward the van der Waals gap. Figure 10f shows that the van der Waals gap between HC and MoSe2 has a height (φ) of 3.93 eV, consistent with the built-in interfacial potential, as derived in the electrostatic potential calculation.

[0090] FIG. 11 shows (a) the results of Raman spectroscopy after 3 months of storage for field effect transistors having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective film according to Preparation Example 1, Example 1, and Comparative Example 1 of the present invention, (b) the output characteristics of Comparative Example 1 without a HC protective film, (c) the output characteristics of Example 1 with a HC protective film, (d) statistics of electron mobility depending on the presence or absence of a protective film depending on the storage period, and (e) statistics of V depending on the presence or absence of a HC protective film. th This is a statistical result of hysteresis.

[0091] Referring to Figure 11, after initial measurements were performed on a field effect transistor having a multilayer MoSe2 channel layer capped with a hydrocarbon (HC) protective layer according to the present invention, the electrical characteristics of the device were measured after two days and three months in air at room temperature to confirm the stability of the hydrocarbon (HC) protective layer. First, Figure 11a shows the results of Raman spectroscopy of the hydrocarbon (HC) protective layer of Preparation Example 1. Even though three months have passed since the initial measurement, the D band and G band are still observed, confirming that the chemical structure of the protective layer is maintained.

[0092] Figure 11b shows the 31 cm 3 months after the first measurement for an unprotected MoSe2FET (denoted as Bare MoSe2FET). 2 V -1 s -1 and the field-effect electron mobility of about 9V th After two days, the transfer curve for MoSe2 exposed to air without a protective film shifts to a positive bias, the hysteresis increases slightly, and the mobility decreases. Further exposure to ambient conditions for three months without a protective film increases the hysteresis by 31 V. th While the conductivity increased to 1000 kJ / cm, the electrical performance decreased significantly. 2 V -1 s -1The adsorption of peripheral molecules on the MoSe2 surface results in carrier confinement by the adsorbed molecules. As the coverage of the adsorbed molecules on the MoSe2 surface increases, the carrier trapping / detrapping process at the air / MoSe2 interface becomes more pronounced, resulting in a significant increase in the hysteresis width. Furthermore, MoSe2 defects or edges formed by exposure to air without a protective film can induce oxidation, which can lead to a degradation of the electrical performance of FET devices.

[0093] On the other hand, initial measurements of MoSe2FETs with a hydrocarbon (HC) protective film (shown in Hydrocarbon Transferred FET) confirmed improved environmental stability, reaching 36 cm 2 V -1 s -1 and a field-effect electron mobility of about 14V th After three months, the hysteresis width was 34cm. 2 V -1 s -1 and about 19V th It was confirmed that there was no significant change in the electrical properties from the initial state. That is, the electron mobility of the field-effect transistor was 36 cm before it was exposed to the external environment. 2 V -1 s -1 34cm after being exposed for 3 months 2 V -1 s -1 It can be seen that the electron mobility decreased by about 5.5%. Also, referring to Figures 11d and 11e, when reproducibility was confirmed between identical field effect transistors, it was confirmed that the hydrocarbon (HC) protective layer provided a passivation effect on the channel layer of the field effect transistor, similar to that described above.

[0094] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, it should be understood by those skilled in the art that the present invention can be embodied in other specific forms without changing the technical concept or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are merely illustrative in all respects and are not limiting. [Explanation of symbols]

[0095] 100 Field-effect transistor 110 Substrate 111 Silicon 112 Dielectric layer 120 channel layer 130 electrodes 140 Protective film

Claims

1. a channel layer provided on the substrate and comprising a transition metal dichalcogenide thin film; a plurality of electrodes disposed on a portion of the channel layer so as to be spaced apart from one another; a protective film covering the channel layer or the channel layer and the electrode, contacting the transition metal dichalcogenide thin film to form a van der Waals gap, and containing a hydrocarbon; Equipped with the protective film maintains the electrical performance of the field-effect transistor even when exposed to an external environment; The field effect transistor retains its electrical performance when exposed to air and oxygen for three months, as measured by a decrease in electron mobility of less than 10%.

2. 2. The field-effect transistor according to claim 1, wherein the hydrocarbon is amorphous and partially contains a crystalline carbon structure shown by a peak (D) at 1350 cm and / or a peak (G) at 1600 cm in Raman spectroscopy.

3. 2. The field effect transistor according to claim 1, wherein the dielectric constant of the protective film is 10 to 40.

4. 2. The field effect transistor according to claim 1, wherein the protective film has a thickness of 0.1 to 5 nm.

5. 2. The field effect transistor of claim 1, wherein the van der Waals gap is 1 to 5 Å.

6. A step (S01) of growing a hydrocarbon thin film on a substrate; A step (S02) of providing a field effect transistor including a channel layer including a transition metal dichalcogenide thin film and a plurality of electrodes arranged spaced apart from each other on a remaining portion of the channel layer; (S03) transferring the hydrocarbon thin film to cover the transition metal dichalcogenide thin film and the electrode, and forming a van der Waals gap between the hydrocarbon thin film and the transition metal dichalcogenide thin film; A method for manufacturing a field effect transistor, comprising:

7. 7. The method of claim 6, wherein the step of growing the hydrocarbon thin film comprises low temperature chemical vapor deposition (LTCVD), inductively coupled plasma chemical vapor deposition (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD), or two or more methods selected from the group consisting of low temperature chemical vapor deposition (LTCVD), inductively coupled plasma-CVD (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD), or a combination of two or more methods selected from the group consisting of low temperature chemical vapor deposition (LTCVD), inductively coupled plasma-CVD (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD), or a combination of two or more methods selected from the group consisting of low temperature chemical vapor deposition (LTCVD), inductively coupled plasma-enhanced chemical vapor deposition ... inductively coupled plasma-enhanced chemical vapor deposition (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD), or a combination of two or more methods

8. 7. The method for manufacturing a field effect transistor according to claim 6, wherein the growth temperature in the step of growing the hydrocarbon thin film is in the range of 500K to 900K.

9. 7. The method for manufacturing a field effect transistor according to claim 6, wherein the hydrocarbon thin film has a dielectric constant of 10 to 40.

10. 7. The method for manufacturing a field-effect transistor according to claim 6, wherein the hydrocarbon thin film is amorphous and partially contains a crystalline carbon structure shown by a peak (D) at 1350 cm and / or a peak (G) at 1600 cm in Raman spectroscopy.

11. 7. The method for producing a field effect transistor according to claim 6, wherein the hydrocarbon thin film has a thickness of 0.1 to 5 nm.

12. 7. The method for manufacturing a field effect transistor according to claim 6, wherein the van der Waals gap is 1 to 5 Å.

13. The hydrocarbon thin film is characterized in that it maintains the electrical performance of the field-effect transistor even when exposed to an external environment, 7. The method of claim 6, wherein the electrical performance of the field effect transistor is maintained by measuring a decrease in electron mobility of less than 10% when exposed to air and oxygen for three months.

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