Method of preparing tellurium oxide thin film and thin film transistor using sputtering

Abstract

To provide a method of preparing a tellurium oxide thin film and a thin film transistor using sputtering.SOLUTION: A method of preparing a semiconductor thin film comprises: (a) providing a target comprising a chalcogen atom and a tellurium atom (Te) comprising at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se); and (b) preparing a semiconductor thin film comprising an amorphous p-type semiconductor by co-deposition on a substrate using the target in an atmosphere of mixed gas comprising argon gas and oxygen gas by a sputtering method. Thereby, a semiconductor thin film and a thin film transistor comprising the same can be provided which has high hole mobility and an excellent on / off ratio of the drain current simultaneously.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a tellurium oxide thin film and a thin film transistor using sputtering. [Background technology]

[0002] Over the past few decades, metal oxide semiconductors have been widely used in transistors, photovoltaics, thermoelectrics, light-emitting diodes, displays, and other applications, driving significant advances in modern optoelectronics research. However, commercially available oxide semiconductors with high electrical performance are all n-type semiconductors that are efficient for electron transport only at room temperature, while the lack of p-type semiconductors capable of hole transport limits their applicability to a wide range of applications. Amorphous a-InGaZnO, a representative n-type semiconductor, has been commercialized as a backplane transistor for driving organic light-emitting diode (OLED) displays. While its highly distributed conduction band minimum (CBM) enables excellent electron transport properties even in its amorphous structure, it lacks p-type characteristics at room temperature. Cu is a p-type metal oxide semiconductor that allows hole transport even at room temperature. x Materials such as O and SnO have been investigated, but they exhibit poor electrical performance, such as low hole field-effect mobility and low on / off current ratio compared to n-type metal oxides. This severely limits the development of pn junction diode-based optoelectronic and CMOS (Complementary Metal Oxide Semiconductor) circuits.

[0003] The main reason why metal oxide semiconductors have poor p-type properties is that the valence band maximum for hole transport in metal oxides is mainly anisotropic and consists of the oxygen 2p orbital, which is relatively small in size and highly localized. + and Sn 2+The metastable cationic valence state of is unstable under air conditions, resulting in poor ambient stability. In this context, the development of stable, high-mobility, low-cost p-type semiconductors is currently of great importance in the microelectronics industry. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention is intended to solve the above-mentioned problems, and its object is to provide high-performance M (M is Se or S) alloyed TeO x The present invention aims to provide a process technology for forming a thin film by sputtering, and for optimizing the composition and amount of alloy to adjust the charge amount and mobility.

[0005] Another object of the present invention is to provide a method for producing TeO films by sputtering deposition. x The present invention aims to provide a new amorphous p-type semiconductor of M, and to provide a high-performance p-channel transistor using this semiconductor thin film.

[0006] Another object of the present invention is to provide a high-performance p-channel TeO film having high stability and high performance at a low processing temperature by sputtering. x The present invention aims to provide a method for manufacturing a thin film transistor.

[0007] It is another object of the present invention to provide large area flexible thin film transistors using low cost sputtering methods. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor thin film, comprising the steps of: (a) providing a target containing chalcogen atoms, including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se), and tellurium atoms (Te); and (b) co-depositing the target on a substrate by a sputtering method in an atmosphere of a mixed gas containing argon gas and oxygen gas, to manufacture a semiconductor thin film containing an amorphous p-type semiconductor.

[0009] The step (a) may include (a-1) providing a first target containing tellurium atoms (Te), and (a-2) providing a second target containing chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se).

[0010] Furthermore, the step (a) may be (a') a step of providing a target containing a mixture of chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se) and tellurium atoms (Te).

[0011] The step (b) may include: (b-1) discharging argon plasma in an argon gas atmosphere; and (b-2) causing the argon plasma to collide with the first target and the second target in an atmosphere of a mixed gas containing the argon gas and oxygen gas, thereby co-depositing atoms of the first target, atoms of the second target, and one or more of their oxides onto the substrate, thereby producing a semiconductor thin film containing a tellurium complex. The plasma discharge pressure in step (b-1) may be 1 to 15 Pa. In step (b-1) or step (b-2), the process operating pressure, which is the total pressure of argon gas and oxygen gas, may be 1 Pa or less, preferably 0.1 to 0.65 Pa. In step (b-1) or step (b-2), the total flow rate of the argon gas and the oxygen gas may be 5 to 50 sccm. In the step (b), the total pressure of the argon gas and the oxygen gas (P Ar +P O2 ) to the oxygen gas partial pressure (P O2 ) ratio (P O2 / (P Ar +P O2 )) can be 0 to 50%.

[0012] In the step (b), the total pressure of the argon gas and the oxygen gas (P Ar +P O2 ) to the oxygen gas partial pressure (P O2 ) ratio (P O2 / (P Ar +P O2 )) can be adjusted to control the oxygen content of the amorphous p-type semiconductor. In the step (b-2), the power (W T1 ) is 10 to 30 W, and the power applied to the second target (W T2 ) can be 1 to 9W. Also, step (b) may be carried out at room temperature. In the step (b), the temperature of the substrate may be 5 to 50°C. Furthermore, the method for producing a semiconductor thin film may further include, after step (b), a step (c) of annealing the semiconductor thin film in air at a temperature of 200 to 300°C. The semiconductor thin film may have a thickness of 2 to 100 nm. The amorphous p-type semiconductor may also contain chalcogen atoms including one or more atoms selected from the group consisting of selenium (Se) atoms and sulfur (S) atoms, and a tellurium complex including tellurium (Te) atoms and tellurium oxide. Additionally, the chalcogen atom may be alloyed with the tellurium complex.

[0013] In addition, the p-type semiconductor may be represented by the following Chemical Formula 1: [Chemical formula 1] TeO x :M During the ceremony, M is a sulfur atom (S) or a selenium atom (Se), x is 0.8≦x≦1.7. Also, x may be characterized as being 1.0≦x≦1.6. In addition, the tellurium atoms of the semiconductor are Te 4+ ionization state of Te 2+ Ionization states of Te and Te 0 The non-ionized state of the ionizable molecule may be included. Additionally, the tellurium oxide may include tellurium monoxide (TeO) and tellurium dioxide (TeO2). The semiconductor may also be oxygen deficient. In addition, the selenium atoms of the semiconductor are Se 2- can include ionization states of The semiconductor may also be for use as a semiconductor thin film in a thin film transistor.

[0014] According to another aspect of the present invention, there is provided a method for manufacturing a thin film transistor, the method including: (1) preparing a stack including a gate electrode and an insulating layer located on the gate electrode; (2) forming a semiconductor thin film, which is manufactured by the method for manufacturing a semiconductor thin film and includes a semiconductor, on the insulating layer of the stack; and (3) forming a source electrode and a drain electrode on the semiconductor thin film.

[0015] According to another aspect of the present invention, there is provided a semiconductor thin film manufactured by the above-described method for manufacturing a semiconductor thin film, wherein the semiconductor thin film comprises an amorphous p-type semiconductor, and the amorphous p-type semiconductor comprises chalcogen atoms including one or more atoms selected from the group consisting of selenium atoms (Se) and sulfur atoms (S), and a tellurium complex including tellurium (Te) atoms and tellurium oxide. [Effects of the Invention]

[0016] TeO produced by the semiconductor thin film manufacturing method of the present invention x The semiconductor thin film channel layer containing Se exhibits high hole field-effect mobility and5 The present invention has the effect of providing a thin film transistor (TFT) that exhibits excellent output / transfer characteristics and excellent electrical performance at an on / off current ratio of . [Brief explanation of the drawings]

[0017] These drawings are to be referred to when describing exemplary embodiments of the present invention, and the technical concept of the present invention should not be interpreted as being limited to the accompanying drawings. [Figure 1] 1 is a schematic diagram illustrating a method for fabricating a semiconductor thin film for use in a selenium-alloyed amorphous p-type thin film transistor using a sputtering process according to the present invention. [Figure 2] 1 is an XPS analysis photograph of Example 6 of the present invention. [Figure 3] 1 is an XPS analysis graph of Example 6 of the present invention and Comparative Example 1. [Figure 4] 1 is a graph showing the results of measuring EXAFS (Extended X-ray absorption fine structure) of the thin film of Example 6 of the present invention. [Figure 5] 1 is a graph showing the results of XRD (X-ray Diffractometer) spectra of the sample immediately after sputtering in Example 1 and the TeOx:Se thin film annealed at 225° C. [Figure 6] FIG. 10 is a diagram showing band gaps calculated by measuring transmittance in the range of 200 nm to 2500 nm for the thin films according to Examples 2 and 4 and Comparative Example 1 and plotting the measured transmittance in a Tauc plot. [Figure 7] 1 is a graph showing the transfer characteristics of TeOx:Se thin film transistors (TFTs) doped with selenium (Se) deposited by a sputtering process according to Examples 1, 2, 3, and 5, and a TeOx thin film transistor (TFT) not doped with selenium (Se) according to Comparative Example 1, depending on the selenium alloy ratio. [Figure 8]10 is a graph showing the transfer characteristics of elements depending on the oxygen partial pressure of TeOx:Se thin film transistors (TFTs) doped with selenium (Se) according to Examples 6, 7, and 8. DETAILED DESCRIPTION OF THE INVENTION

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily understand the present invention. However, the following description does not limit the present invention to specific embodiments, and when describing the present invention, if it is determined that a specific description of related known technology may obscure the gist of the present invention, the detailed description will be omitted.

[0019] The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly dictates otherwise. In this application, the terms "comprise" or "have" and the like are intended to specify the presence of features, numbers, steps, operations, components, or combinations thereof described in the specification, and should be understood not to preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, or combinations thereof.

[0020] Furthermore, terms including ordinal numbers, such as "first" and "second," may be used below to describe various components, but these components are not limited by these terms. These terms are used only to distinguish one component from another. For example, a first component can be named a second component, and similarly, a second component can be named a first component, without departing from the scope of the present invention.

[0021] Furthermore, when a component is said to be "formed" or "laminated" on another component, it should be understood that the component may be formed or laminated in direct contact with the entire surface or one side of the surface of the other component, or that there may be another component interposed therebetween.

[0022] The method for fabricating a selenium-alloyed tellurium oxide thin film and a thin film transistor using sputtering according to the present invention will be described in detail below, but this is provided as an example and is not intended to limit the present invention, which is defined only by the scope of the claims that follow.

[0023] According to one aspect of the present invention, there is provided a method for manufacturing a semiconductor thin film, comprising: (a) providing a target containing chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se) and tellurium atoms (Te); and (b) co-depositing the target on a substrate by a sputtering method in an atmosphere of a mixed gas containing argon gas and oxygen gas to manufacture a semiconductor thin film containing an amorphous p-type semiconductor.

[0024] The step (a) may include (a-1) providing a first target containing tellurium atoms (Te), and (a-2) providing a second target containing chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se).

[0025] Furthermore, the step (a) may be a step (a') of providing a target containing a mixture of chalcogen atoms including one or more atoms selected from the group consisting of sulfur atoms (S) and selenium atoms (Se) and tellurium atoms (Te).

[0026] The step (b) can include: (b-1) discharging argon plasma in an argon gas atmosphere; and (b-2) causing the argon plasma to collide with the first target and the second target in an atmosphere of a mixed gas containing the argon gas and oxygen gas, thereby co-depositing atoms of the first target, atoms of the second target, and one or more of their oxides onto the substrate, thereby producing a semiconductor thin film containing a tellurium complex.

[0027] The plasma discharge pressure in step (b-1) may be 1 to 15 Pa. Here, if the plasma discharge pressure is less than 1 Pa, it is not preferable because there will be insufficient particles to cause discharge, and if the plasma discharge pressure is more than 15 Pa, it is not preferable because impurities may be included in the thin film.

[0028] In step (b-1) or step (b-2), the process pressure, which is the total pressure of the argon gas and the oxygen gas, may be 1 Pa or less, preferably 0.1 to 0.65 Pa. If the process pressure exceeds 1 Pa, it is undesirable because a thin film containing impurities or having low density may be formed. In particular, if the process pressure is less than 0.1 Pa, it is undesirable because the plasma becomes unstable.

[0029] In step (b-1) or step (b-2), the total flow rate of argon gas and oxygen gas may be 5 to 50 sccm. If the total flow rate is less than 5 sccm, plasma generation is not easy, which is undesirable, and if the total flow rate is more than 50 sccm, film uniformity is poor, which is undesirable.

[0030] In the step (b), the total pressure (P Ar +P O2 ) to the oxygen gas partial pressure (P O2 ) ratio (P O2 / (P Ar +P O2 )) can be 0 to 50%. Here, the oxygen gas partial pressure (PO2 ) ratio (P O2 / (P Ar +P O2 )) exceeds 50%, this is not preferable because it results in a tellurium dioxide (TeO2) thin film with a low hole carrier concentration.

[0031] In the step (b), the total pressure (P Ar +P O2 ) to the oxygen gas partial pressure (P O2 ) ratio (P O2 / (P Ar +P O2 )) can be adjusted to control the oxygen content of the amorphous p-type semiconductor.

[0032] In the step (b-2), the power (W T1 ) can be 10 to 30 W. Here, the power (W T1 If the power is less than 10 W, the plasma discharge voltage is low, which is not preferable, and if it exceeds 30 W, the deposition rate is too high or the target is damaged, which is not preferable.

[0033] In addition, the power (W) applied to the second target T2 The power (W) applied to the second target can be 1 to 15 W. T2 If the power (W) applied to the second target is less than 1 W, the plasma discharge voltage is low and this is undesirable. T2 If the power exceeds 15 W, the deposition rate will be too high or the target will be damaged, which is undesirable.

[0034] Also, step (b) may be carried out at room temperature. In step (b), the substrate temperature may be 5 to 50° C. Here, if the substrate temperature is less than 5° C., the effective collision energy of the thin film will be low, making it difficult to form the thin film, which is not preferable, and if the substrate temperature is more than 50° C., a crystalline thin film will be formed, which is not preferable.

[0035] The method for manufacturing the semiconductor thin film may further include, after step (b), (c) annealing the semiconductor thin film in air at a temperature of 200 to 300° C. Here, if the annealing temperature is less than 200° C., the hole concentration of the thin film is undesirably low, whereas if the annealing temperature is more than 300° C., pinholes may be formed or excessive recrystallization may occur within the thin film, which is undesirable.

[0036] The thickness of the semiconductor thin film may be 2 to 100 nm. If the thickness of the semiconductor thin film is less than 2 nm, the charge amount is small and it is difficult to obtain sufficient thin film coverage, which is undesirable. If the thickness of the thin film is too thick, exceeding 100 nm, the charge amount is too high and it is undesirable as a semiconductor layer of a transistor.

[0037] The amorphous p-type semiconductor may also contain chalcogen atoms including one or more atoms selected from the group consisting of selenium (Se) atoms and sulfur (S) atoms, and a tellurium complex including tellurium (Te) atoms and tellurium oxide.

[0038] In addition, the chalcogen atom may be alloyed with the tellurium complex. In addition, the p-type semiconductor may be represented by the following Chemical Formula 1. [Chemical formula 1] TeO x :M During the ceremony, M is a sulfur atom (S) or a selenium atom (Se), x can be 0.8≦x≦1.7, where if x is less than 0.8, a large number of Te-Te bonds are contained, resulting in a high charge amount, which is undesirable for a transistor semiconductor layer, and if x is more than 1.7, the charge amount is too low, which is undesirable. M may be more than 0 and not more than 25 atom% based on the total atoms of Te atoms, O atoms, and M atoms. Here, when M is 0 atom%, the charge amount is high and the off current in the device is high, which is undesirable, and when M is more than 25 atom%, the hole mobility is low due to the high doping amount, which is undesirable.

[0039] The tellurium atoms in the semiconductor are Te 4+ ionization state of Te 2+ Ionization states of Te and Te 0 wherein the semiconductor can include the Te 2+ and Te 0 The shallow acceptor state formed by the 5p orbital of can be used as a hole conduction channel.

[0040] Additionally, the tellurium oxide may include tellurium monoxide (TeO) and tellurium dioxide (TeO2).

[0041] The semiconductor may also be in an oxygen-deficient state, which means that the ratio of oxygen in the stoichiometric ratio of tellurium (Te):oxygen (O) is less than 1:2.

[0042] In addition, the selenium atoms of the semiconductor are Se 2- Here, the ionization state of the semiconductor Se may be 2- The oxygen vacancies are passivated, allowing the partially vacant 4p state to be used as a hole conduction channel. At this time, the Te-Se cation-anion bond is formed, maximizing the overlap between the cation 5p orbital and the anion 4p orbital, allowing for smooth hole transfer.

[0043] The semiconductor thin film may also be for use as a semiconductor layer in a thin film transistor.

[0044] According to another aspect of the present invention, there is provided a method for manufacturing a thin film transistor, the method including: (1) preparing a stack including a gate electrode and an insulating layer located on the gate electrode; (2) forming a semiconductor thin film, which is manufactured by the method for manufacturing a semiconductor thin film and includes a semiconductor, on the insulating layer of the stack; and (3) forming a source electrode and a drain electrode on the semiconductor thin film.

[0045] According to another aspect of the present invention, there is provided a semiconductor thin film manufactured by the above-described method for manufacturing a semiconductor thin film, the semiconductor thin film including an amorphous p-type semiconductor, the amorphous p-type semiconductor including chalcogen atoms including one or more atoms selected from the group consisting of selenium atoms (Se) and sulfur atoms (S), and a tellurium complex including tellurium (Te) atoms and tellurium oxide.

[0046] The semiconductor may also be for use in a semiconductor thin film of a thin film transistor. The thickness of the semiconductor thin film may be 2 nm or more, preferably 2 to 100 nm. Here, if the thickness of the semiconductor thin film is less than 2 nm, the charge amount is small, making it difficult to obtain sufficient thin film coverage, which is undesirable. If the thickness of the thin film is too thick, exceeding 100 nm, the charge amount is too high, making it undesirable for use as a semiconductor layer in a thin film transistor.

[0047] According to another aspect of the present invention, there is provided a thin film transistor including: a gate electrode; an insulating layer located on the gate electrode; a semiconductor thin film located on the insulating layer and including a semiconductor according to the present invention; and a source electrode and a drain electrode located spaced apart from each other on the semiconductor thin film.

[0048] In addition, the gate electrode may include at least one material selected from the group consisting of n-doped silicon (n-doped Si), p-doped silicon (p-doped Si), gold (Au), silver (Ag), platinum (Pt), titanium (Ti), aluminum (Al), tungsten (W), magnesium (Mg), calcium (Ca), ytterbium (Yb), chromium (Cr), nickel (Ni), molybdenum (Mo), gold oxide, platinum oxide, silver oxide, palladium oxide, iron oxide, graphene, carbon nanotubes (CNT), silver nanowires (Ag NW), indium tin oxide, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS).

[0049] In addition, the source electrode and the drain electrode may each include at least one material selected from the group consisting of gold (Au), silver (Ag), platinum (Pt), titanium (Ti), aluminum (Al), tungsten (W), magnesium (Mg), calcium (Ca), ytterbium (Yb), chromium (Cr), nickel (Ni), molybdenum (Mo), gold oxide, platinum oxide, silver oxide, palladium oxide, iron oxide, graphene, carbon nanotubes (CNT), silver nanowires (Ag NW), indium tin oxide, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS).

[0050] The insulating layer may include one or more materials selected from the group consisting of silicon dioxide, glass, quartz, alumina, silicon carbide, magnesium oxide, polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polystyrene (PS), polyimide (PI), polyvinyl chloride (PVC), polyvinylpyrrolidone (PVP), polyethylene (PE), silicon oxide (SiO2), germanium, polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA), zirconium oxide (ZrO2), aluminum oxide (AlO2), and hafnium oxide (HfO2).

[0051] [Example] The present invention will be described below with reference to preferred examples, but these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Example: Fabrication of amorphous p-type thin film transistors [Changes in the Te:Se composition ratio] Example 1: Te:Se = 93:7 (atom %:atom %) TeOx;Se (x = 1.31) FIG. 1 is a schematic diagram illustrating a method for fabricating a semiconductor thin film for use in a selenium-alloyed amorphous p-channel thin film transistor using a sputtering process according to the present invention. Referring to Figure 1, co-sputtering was performed using a Te target and a Se target simultaneously to deposit a selenium-alloyed tellurium oxide-based semiconductor film. Both Te and Se targets were used with a φ25.4 target. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced. The total flow rate of argon gas and oxygen was 20 sccm, and the partial pressure of oxygen gas was 0%. The powers applied to the targets during the process were 20 W for Te and 2 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO xThe base film was deposited to a thickness of 25 nm or less. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. Here, the selenium-alloy tellurium oxide, TeO x The atom % ratio of Te:Se in Se was 93:7 (atom %:atom %), and x was 1.31.

[0052] Example 2: Te:Se=85:15 (atom%:atom%) TeO x ;Se(x=1.17) Referring to Figure 1, co-sputtering was performed using a Te target and a Se target simultaneously to deposit a selenium-alloyed tellurium oxide-based semiconductor film. Both Te and Se targets were used with a φ25.4 target. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced. The total flow rate of argon gas and oxygen was 20 sccm, and the partial pressure of oxygen gas was 0%. The powers applied to the targets during the process were 20 W for Te and 5 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was within approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of 25 nm or less. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. Here, the selenium-alloy tellurium oxide, TeO x The atom % of Te:Se in Se was 85:15 (atom %:atom %), and x was 1.17.

[0053] Example 3: Te:Se=75:25 (atom%:atom%) TeO x ;Se(x=0.99) Referring to Figure 1, co-sputtering was performed using a Te target and a Se target simultaneously to deposit a selenium-alloyed tellurium oxide-based semiconductor film. Both Te and Se targets were used with a φ25.4 target. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced. The total flow rate of argon gas and oxygen was 20 sccm, and the partial pressure of oxygen gas was within 0%. The powers applied to the targets during the process were 20 W for Te and 8 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was approximately 40 cm or less. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of less than 25 nm. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin-film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. The atom % ratio of Te:Se in the selenium alloy tellurium oxide, TeOx;Se, was 75:25 (atom %:atom %), where x was 0.99.

[0054] Example 4: Te:Se = 68:32 (atom %:atom %) TeO x ;Se Referring to Figure 1, co-sputtering was performed using a Te target and a Se target simultaneously to deposit a selenium-alloyed tellurium oxide-based semiconductor film. Both Te and Se targets were used with a φ25.4 target. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced. The total flow rate of argon gas and oxygen was 20 sccm, and the partial pressure of oxygen gas was 0%. The powers applied to the targets during the process were 20 W for Te and 10 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was within approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of 25 nm or less. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. Here, the selenium-alloy tellurium oxide, TeO x The atom % ratio of Te:Se in Se was 68:32 (atom %:atom %).

[0055] Example 5: Te:Se = 64:36 (atom %:atom %) TeO x ;Se(x=1.01) Referring to Figure 1, co-sputtering was performed using a Te target and a Se target simultaneously to deposit a selenium-alloyed tellurium oxide-based semiconductor film. Both Te and Se targets were used with a φ25.4 target. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced. The total flow rate of argon gas and oxygen was 20 sccm, the partial pressure of oxygen gas was 0%, and the power applied to the target during the process was 20 W for Te and 12 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was within approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of 25 nm or less. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. Here, the selenium-alloy tellurium oxide, TeO x The atom % ratio of Te:Se in Se was 64:36 (atom %:atom %), and x was 1.01.

[0056] [Changes in oxygen composition ratio] Example 6: O 2 Gas / Ar gas partial pressure ratio = 0% To deposit a selenium-alloyed tellurium oxide-based semiconductor film, co-sputtering was performed using a Te target and a Se target. Both Te and Se targets were φ25.4 mm in size. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas was introduced. The argon gas flow rate was 20 sccm, and the oxygen gas partial pressure was 0%. The powers applied to the targets during the process were 20 W for Te and 5 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was approximately 40 cm or less. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeOx The base film was deposited to a thickness of less than 20 nm. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. The selenium-alloy tellurium oxide (TeO) was used. x The atom % ratio of Te:Se in Se was 85:15, and x was 1.17.

[0057] Example 7: O 2 Gas / Ar gas partial pressure ratio = 2.5% To deposit a selenium-alloyed tellurium oxide-based semiconductor film, co-sputtering was performed using a Te target and a Se target. Both Te and Se targets were φ25.4 mm in size. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon and oxygen gases were introduced. The total flow rate of argon and oxygen gases was 20 sccm, and the partial pressure of oxygen gas was 2.5%. The powers applied to the targets during the process were 20 W for Te and 5 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of less than 20 nm. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. The selenium-alloy tellurium oxide (TeO) was used. x The atom % ratio of Te:Se in Se was 85:15.

[0058] Example 8: O 2 Gas / Ar gas partial pressure ratio = 5.0% To deposit a selenium-alloyed tellurium oxide-based semiconductor film, co-sputtering was performed using a Te target and a Se target. Both Te and Se targets were φ25.4 mm in size. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon and oxygen gases were introduced. The total flow rate of argon and oxygen gases was 20 sccm, and the partial pressure of oxygen gas was 5.0%. The powers applied to the targets during the process were 20 W for Te and 5 W for Se, respectively. The substrate temperature was 25°C, and the distance between the target and the substrate was approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. Selenium-alloyed TeO x The base film was deposited to a thickness of less than 20 nm. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. The selenium-alloy tellurium oxide (TeO) was used. x The atom % ratio of Te:Se in Se was 85:15 (atom %:atom %).

[0059] Comparative Example 1: Pristine tellurium oxide Te:Se=100:0 (atom %:atom %) TeO x (x=1.25) Referring to Figure 1, co-sputtering was performed using a Te target to deposit a tellurium oxide-based semiconductor film alloyed with selenium. A Te target with a standard φ25.4 size was used. The sputtering process was carried out at room temperature with a plasma discharge pressure of 7 Pa and a process operating pressure of 0.65 Pa or less, and argon gas and oxygen were introduced to carry out the reaction. The total flow rate of argon gas and oxygen gas was 20 sccm, and the partial pressure of argon gas was within 100%. The power applied to the target during the process was 20 W for each Te target. The substrate temperature was 25°C, and the distance between the target and the substrate was within approximately 40 cm. Pre-sputtering was performed for approximately 5 minutes to clean the target surface before deposition. TeO xThe base film was deposited to a thickness of 25 nm. The deposited sample was annealed in air at 225°C for 30 minutes. Then, thin film transistors (TFTs) were fabricated by depositing source and drain electrodes using Ni. Here, the pristine tellurium oxide (TeO) was used. x The atom % ratio of Te:Se in the film was 100:0 (atom %:atom %), and x was 1.25.

[0060] [Test example] Test Example 1: Analysis of Te:Se composition ratio in semiconductor thin film 2 is an XPS analysis photograph of Example 6 of the present invention. Referring to FIG. 2 and Table 1 below, the composition ratios of Examples 1 to 8 and Comparative Example 1 were confirmed based on the peak areas of Te and Se.

[0061] Test Example 2: Semiconductor thin film TeO x x measurement of The TeO of the semiconductor thin films of Examples 1 to 3, Examples 5 and 6, and Comparative Example 1 was analyzed by XPS (X-ray photoelectron spectroscopy). x :Se or TeO x The results of measuring x are shown in Table 1.

[0062] Test Example 3: TeO x Investigation of the ionization state of Se in: XPS analysis 3 is an XPS analysis graph of Example 6 of the present invention and Comparative Example 1. Referring to FIG. 3, Se is amorphous TeO x XPS was performed to investigate the state of Se. 2- This confirmed that Se exists in the TeO x It is found that the amorphous thin film exists in a Se-Te bond state, and in this case, Te 2+ It can be predicted that it will bind to

[0063] Test Example 4: Se-Te bond analysis: EXAFS (Extended X-ray absorption fine structure) 4 is a graph showing the results of measuring EXAFS (Extended X-ray absorption fine structure) of the thin film of Example 6. Referring to FIG. 4, the results of measuring EXAFS (Extended X-ray absorption fine structure) of the thin film of Example 6 confirmed that Se-Te bonding exists when the intensity is observed according to the radial distance at the Se K-edge.

[0064] Test Example 5: XRD (X-ray Diffractometer) FIG. 5 shows the results of the as-sputtered sample of Example 1 and the TeO annealed at 225° C. x 5 is a graph showing the XRD (X-ray Diffractometer) spectrum of the TeO:Se thin film. x It can be confirmed that the crystallinity of the :Se thin film is amorphous.

[0065] Test Example 6: Bandgap Measurement Fig. 6 shows bandgaps calculated by Tauc plotting transmittance measured in the range of 200 nm to 2500 nm for the thin films of Example 2, Example 4, and Comparative Example 1. Referring to Fig. 6, it can be seen that the bandgap decreases in Comparative Example 1, which is a tellurium oxide containing selenium at a certain alloy content or less (≦15%), but increases in Examples 2 and 4, which contain more selenium.

[0066] Test Example 7: TeO x Transfer characteristics of :Se TFT FIG. 7 shows the selenium (Se)-doped TeO deposited by the sputtering process according to Examples 1, 2, 3, and 5. x : Se thin film transistor (TFT), and TeO not doped with selenium (Se) according to Comparative Example 1 x 1 is a graph showing transfer characteristics of thin film transistors (TFTs) depending on the selenium alloy ratio. 7, it was confirmed that Example 1 and Comparative Example 1, which were doped with selenium (Se) at less than 15 atom%, exhibited the highest hole mobility, while Examples 2, 3, and 5, which were doped with selenium (Se) at 15 atom% or more, exhibited reduced charge.

[0067] In addition, selenium (Se)-doped TeO deposited by the sputtering process according to Examples 1, 2, 3, and 5 x : Se thin film transistor (TFT), and TeO not doped with selenium (Se) according to Comparative Example 1 x The hole mobility and on / off ratio of the drain current of the thin film transistor (TFT) are shown in the following Table 1. In Table 1, Example 2 and Example 6 are operated under the same conditions, but there is a difference in performance due to the difference in the thickness of the channel layer.

[0068] [Table 1]

[0069] Test Example 8: Transfer characteristics of TFT depending on oxygen partial pressure during sputtering process FIG. 8 shows the selenium (Se)-doped TeO according to Examples 6, 7, and 8. x 8 is a graph showing the transfer characteristics of a Se thin film transistor (TFT) as a function of oxygen partial pressure. Referring to Figure 8, it can be seen that as the oxygen partial pressure increases, the charge amount in the tellurium oxide thin film decreases, causing the Ids curve to decrease. This can be considered as a decrease in the Te-Te bonds, resulting in a decrease in the charge amount in the film. The scope of the present invention is indicated by the claims set forth below rather than by the above detailed description, and all changes and modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included within the scope of the present invention.

Claims

1. (a) providing a target containing chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se) and tellurium atoms (Te); (b) co-depositing the target on a substrate by a sputtering method in an atmosphere of a mixed gas containing argon gas and oxygen gas to produce a semiconductor thin film containing an amorphous p-type semiconductor.

2. The step (a) (a-1) providing a first target containing tellurium atoms (Te); (a-2) providing a second target containing chalcogen atoms including at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se).

3. The step (a) 2. The method for manufacturing a semiconductor thin film according to claim 1, further comprising the step of: (a') providing a target containing a mixture of chalcogen atoms containing at least one selected from the group consisting of sulfur atoms (S) and selenium atoms (Se) and tellurium atoms (Te).

4. The step (b) (b-1) discharging argon plasma in an argon gas atmosphere; (b-2) causing the argon plasma to collide with the first target and the second target in an atmosphere of a mixed gas containing the argon gas and the oxygen gas, thereby co-depositing atoms of the first target, atoms of the second target, and one or more of an oxide thereof onto the substrate, thereby producing a semiconductor thin film containing a tellurium complex.

5. 5. The method for producing a semiconductor thin film according to claim 4, wherein the plasma discharge pressure in said step (b-1) is 1 to 15 Pa.

6. 5. The method for manufacturing a semiconductor thin film according to claim 4, wherein in step (b-1) or step (b-2), a process working pressure, which is a total pressure of argon gas and oxygen gas, is 1 Pa or less.

7. 5. The method for producing a semiconductor thin film according to claim 4, wherein in the step (b-1) or the step (b-2), the total flow rate of the argon gas and the oxygen gas is 5 to 50 sccm.

8. In the step (b), the total pressure (P Ａｒ +P Ｏ２ ) relative to the oxygen gas partial pressure (P Ｏ２ ) ratio (P Ｏ２ / (P Ａｒ +P Ｏ２ 5. The method for producing a semiconductor thin film according to claim 4, wherein the ratio of the total number of nuclei to the total number of nuclei is 0 to 50%.

9. In the step (b), the total pressure (P Ａｒ +P Ｏ２ ) relative to the oxygen gas partial pressure (P Ｏ２ ) ratio (P Ｏ２ / (P Ａｒ +P Ｏ２ 5. The method for manufacturing a semiconductor thin film according to claim 4, wherein the oxygen content of the amorphous p-type semiconductor is controlled by adjusting the temperature.

10. 2. The method for manufacturing a semiconductor thin film according to claim 1, wherein the step (b) is carried out at room temperature.

11. The method for producing a semiconductor thin film further comprises, after step (b), 2. The method for producing a semiconductor thin film according to claim 1, further comprising the step of: (c) annealing said semiconductor thin film in air at a temperature of 200 to 300° C.

12. The amorphous p-type semiconductor is chalcogen atoms including at least one selected from the group consisting of selenium atoms (Se) and sulfur atoms (S); 2. The method for producing a semiconductor thin film according to claim 1, further comprising: a tellurium complex containing tellurium (Te) atoms and tellurium oxide.

13. 13. The method of claim 12, wherein the chalcogen atoms are alloyed with the tellurium complex.

14. 13. The method for manufacturing a semiconductor thin film according to claim 12, wherein the p-type semiconductor is represented by the following Chemical Formula 1: [Chemical formula 1] TeO ｘ :M (In the formula, M is a sulfur atom (S) or a selenium atom (Se), and x is 0.8≦x≦1.7.)

15. The tellurium atoms in the semiconductor are Te ４＋ ionization state of Te ２＋ and Te ０ The method for producing a semiconductor thin film according to claim 12, wherein the non-ionized state of

16. The tellurium oxide is tellurium monoxide (TeO) and tellurium dioxide (TeO ２ 13. The method for producing a semiconductor thin film according to claim 12, comprising the steps of:

17. 2. The method for producing a semiconductor thin film according to claim 1, wherein the semiconductor is in an oxygen-deficient state.

18. (1) providing a stack including a gate electrode and an insulating layer located on the gate electrode; (2) forming a semiconductor thin film, which is manufactured by the method of claim 1 and contains a semiconductor, on the insulating layer of the laminate; (3) forming a source electrode and a drain electrode on the semiconductor thin film.

19. A semiconductor thin film manufactured by the method of manufacturing a semiconductor thin film according to claim 1, the semiconductor thin film contains an amorphous p-type semiconductor, The amorphous p-type semiconductor is chalcogen atoms including at least one selected from the group consisting of selenium atoms (Se) and sulfur atoms (S); a tellurium complex containing tellurium (Te) atoms and tellurium oxide.

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