Method for manufacturing single-crystal copper thin film having nonlinear hall effect and hole carrier dominant transport phenomenon in two-dimensional single-crystal thin film with suppressed grain boundary, and single-crystal copper thin film and single-crystal copper thin film semiconductor manufactured by using same

Abstract

The present invention relates to a single-crystal copper thin film and a single-crystal copper thin film semiconductor, which utilize a phenomenon in which holes, rather than electrons, become carriers when a grain boundary (GB) is removed from a copper thin film having a thickness of 200 nm or less. More specifically, the present invention relates to a copper thin film and a single-crystal copper thin film semiconductor, of which electrical properties change to resemble those of a p-type semiconductor under certain conditions. In the single-crystal thin film having a suppressed grain boundary, according to the present invention, a single-crystal copper thin film having a nonlinear hole effect and a hole carrier dominant transport phenomenon includes a single-crystal copper thin film having a thickness of 200 nm or less, wherein the grain boundary is suppressed.

Description

A method for manufacturing a single-crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single-crystal thin film with suppressed grain boundaries, and a single-crystal copper thin film and a single-crystal copper thin film semiconductor manufactured using the same.

[0001] The present invention relates to a single-crystal copper thin film and a single-crystal copper thin film semiconductor that utilize a phenomenon in which holes, rather than electrons, become carriers when grain boundaries are removed from a copper thin film having a thickness of 200 nm or less, and more specifically, to a copper thin film and a single-crystal copper thin film semiconductor whose electrical properties are changed to a form similar to a p-type semiconductor under specific conditions.

[0002]

[0003] It is well known that the carrier in copper is electron. Copper has 10 23 / cm3 electron concentration and 1.72 X 10 -8 Copper has a room temperature resistance of Ωcm, which means it has the second highest electrical conductivity after silver (Ag), so it is mainly used as an electrode or conductor for current flow, and it is difficult to perform a special purpose function.

[0004] On the other hand, depending on the type of semiconductor, some have electrons as the primary carrier (n-type), while others have holes (p-type). When an n-type and a p-type semiconductor are joined to form a pn junction, the flow of current becomes asymmetrical, which is an important characteristic that makes it useful as a device.

[0005] If n-type and p-type characteristics can be realized using only copper, it could be a groundbreaking invention that would allow for both electrode and element functions to be achieved simultaneously using only copper without introducing semiconductor materials.

[0006]

[0007] The present invention has been devised to solve the above problems, and the purpose of the present invention is to manufacture a copper thin film that can implement n-type and p-type characteristics using only copper by modifying the electron orbit of copper to solve the defects of general copper.

[0008] The technical problems to be solved by the invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0009]

[0010] (1) Single crystal copper thin film

[0011] A single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries according to the present invention,

[0012] A single crystal copper thin film having a thickness of 200 nm or less, characterized in that grain boundaries are suppressed.

[0013] In addition, the single crystal copper thin film is characterized by a nonlinear behavior of Hall resistance according to a magnetic field.

[0014] In addition, the single crystal copper thin film is characterized by growing copper by atomic ASE on a sapphire substrate.

[0015] Additionally, the single crystal copper thin film is characterized in that the Hall resistance exhibits nonlinear behavior as the temperature changes.

[0016]

[0017] (2) Single crystal copper thin film semiconductor

[0018] A single crystal copper thin film having a thickness of 200 nm or less, wherein the single crystal copper thin film is characterized in that grain boundaries are suppressed and electrical characteristics are transformed into p-type.

[0019] In addition, the single crystal copper thin film is characterized by a nonlinear behavior of Hall resistance according to a magnetic field.

[0020] In addition, the single crystal copper thin film is characterized by growing copper by atomic ASE on a sapphire substrate.

[0021] Additionally, the single crystal copper thin film is characterized in that the Hall resistance exhibits nonlinear behavior as the temperature changes.

[0022]

[0023] (3) Method for manufacturing single crystal copper thin film

[0024] It is characterized by being manufactured by growing a copper thin film by RF sputtering copper at 160 to 180°C.

[0025] In addition, the initial pressure of the above RF sputtering is 2.0×10 -3 2.5×10 -3 It is characterized by being Pa.

[0026] In addition, the RF sputtering is characterized in that it is performed in an Ar gas atmosphere.

[0027] In addition, the RF sputtering is characterized by controlling the pressure by injecting Ar gas at 0.3 to 0.7 Pa.

[0028] In addition, the RF output of the RF sputtering is characterized by being 23 to 27 W.

[0029] In addition, the rotation speed of the RF sputtering is characterized by being 25 to 35 RPM.

[0030]

[0031] By means of solving the above problem, the present invention can solve the defects of general copper, lengthen the mean free path of electrons, and thereby change the structure of the Fermi surface where the existing electrons stay, thereby modifying the orbit of the electrons.

[0032] In addition, the present invention can manufacture a copper thin film that is designed to implement n-type and p-type characteristics using only copper by modifying the copper electron orbit.

[0033]

[0034] Figure 1 is a graph measuring the Hall effect of general copper or 3D bulk copper.

[0035] Figure 2 is a Fermi surface of 3D copper, which is a ring pattern for inducing asymmetric magnetoresistance according to the forward (a) and reverse (b) directions of current.

[0036] Figure 3 is a surface view of the Fermi surface of 2D copper in a periodic zone scheme.

[0037] Figure 4 shows the Fermi surface (a) obtained from a 2D single crystal copper thin film through ARPES measurement, and (b) shows the results measured in the direction of the orange arrow in (a) as an energy axis.

[0038] Figure 5 is a graph showing the Hall effect measurement results of single crystal copper films of various thicknesses, including the results of nonlinear Hall effect measurements of polycrystalline copper (PCCF) with a thickness of 82 nm (a), 205 nm (b), 80 nm (c), 40 nm (d), 12 nm (e), and 10 nm (f) thick SCCF.

[0039] Figure 6 shows EBSD (column 1), misorientation lines (column 2), Hall effect measurements (column 3), and grain boundary (GB) and twin boundary (TB) diagrams (column 4) of a 40 nm thick thin film, including a polycrystalline thin film (a), a thin film close to a single crystal grown by the ASE method, with GBs controlled differently (b) to (d), and a completely single crystal thin film without any grain boundaries (e).

[0040]

[0041] The terms used in this specification will be briefly explained, and the present invention will be described in detail.

[0042] The terms used in this invention have been selected from widely used, common terms, taking into account their functions. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Therefore, the terms used in this invention should be defined based on their meaning and the overall content of the invention, rather than simply their names.

[0043] When a part of a specification is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0044] Below, with reference to the attached drawings, embodiments of the present invention are described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0045] Specific details, including the problems to be solved, means of solving them, and the effects of the invention, are included in the embodiments and drawings described below. The advantages and features of the present invention, and methods for achieving them, will become clearer with reference to the embodiments described below in detail, along with the accompanying drawings.

[0046]

[0047] (1) Single crystal copper thin film

[0048] A single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominated transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries according to the present invention comprises a single crystal copper thin film having a thickness of 200 nm or less, characterized in that grain boundaries are suppressed. More specifically, it can be confirmed that a single crystal copper thin film having a thickness of 40 nm or less has the most effective suppression of grain boundaries.

[0049] The above single crystal copper thin film is characterized by a nonlinear behavior of Hall resistance according to a magnetic field.

[0050] The above single crystal copper thin film is characterized by growing copper by atomic ASE on a sapphire substrate.

[0051] The above single crystal copper thin film is characterized by nonlinear behavior of Hall resistance as temperature changes.

[0052]

[0053] (2) Single crystal copper thin film semiconductor

[0054] A single-crystal copper thin film having a thickness of 200 nm or less, wherein the single-crystal copper thin film is characterized by suppressing grain boundaries and transforming electrical properties to p-type. More specifically, it can be confirmed that a single-crystal copper thin film having a thickness of 40 nm or less has the most effective suppression of grain boundaries.

[0055] The above single crystal copper thin film is characterized by a nonlinear behavior of Hall resistance according to a magnetic field.

[0056] The above single crystal copper thin film is characterized by growing copper by atomic ASE on a sapphire substrate.

[0057] The above single crystal copper thin film is characterized by nonlinear behavior of Hall resistance as temperature changes.

[0058]

[0059] (3) Method for manufacturing single crystal copper thin film

[0060] It is characterized by being manufactured by growing a copper thin film by RF sputtering at 160 to 180°C. More specifically, it is preferable to grow a copper thin film by RF sputtering at 170°C.

[0061] The initial pressure of the above RF sputtering is 2.0×10 -3 2.5×10 -3 It is characterized by Pa. More specifically, 2.3×10 -3 It is preferable to be Pa.

[0062] In addition, the RF sputtering is characterized in that it is performed in an Ar gas atmosphere.

[0063] In addition, the RF sputtering is characterized by controlling the pressure by injecting Ar gas at 0.3 to 0.7 Pa. More specifically, it is preferably 0.5 Pa.

[0064] In addition, the RF output of the RF sputtering is characterized by being 23 to 27 W. More specifically, it is preferably 25 W.

[0065] In addition, the rotation speed of the RF sputtering is characterized by being 25 to 35 RPM. More specifically, it is preferably 30 RPM.

[0066]

[0067] Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

[0068]

[0069] The present invention relates to a single-crystal copper thin film that utilizes the phenomenon in which holes, rather than electrons, become carriers when grain boundaries are removed from a copper thin film having a thickness of 200 nm or less, and is a copper thin film whose electrical properties are changed to a form similar to a p-type semiconductor under specific conditions. This can be performed by completely resolving defects of general copper and changing the structure of the Fermi surface where electrons normally reside by lengthening the mean free path of electrons.

[0070] A single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries according to the present invention comprises a single crystal copper thin film having a thickness of 200 nm or less, characterized in that grain boundaries (hereinafter referred to as GBs) are suppressed.

[0071] In addition, the single crystal copper thin film is characterized by a nonlinear behavior of Hall resistance according to a magnetic field.

[0072] In addition, the single crystal copper thin film is characterized by growing copper by atomic ASE on a sapphire substrate.

[0073]

[0074] Typically, the Hall effect in copper exhibits a linear behavior. This is due to the single carrier, meaning that the Hall resistance increases linearly with increasing magnetic field and does not significantly change with temperature. As shown in Figure 1, the Hall effect of conventional copper or 3D bulk copper is demonstrated, and it can be seen that the Hall resistance increases linearly with increasing magnetic field.

[0075] Solid-state electronic devices, including transistors, diodes, and various sensors, rely on the flow and control of conduction electrons in semiconductor channels and metal electrodes. Among the various properties of a material, the electronic band structure near the Fermi surface determines the behavior of conduction electrons, a key feature utilized in device applications and design. Consequently, charge carrier polarity, density, and mobility have been engineered and optimized for semiconductors. However, effective design of electronic properties has not been applied to other important electronic components, including noble metals such as copper (Cu), conceptually limiting the full potential of these materials for novel devices.

[0076] The Fermi surface of metals is overwhelmed by random scattering from numerous defects such as GBs during transport. GBs are ~10 2 μm -2 (10 10 cm -2) are formed at a density greater than or equal to GBs, making them difficult to avoid. The transport of electrons and phonons is reported to be critically affected by GBs, especially when the mean free path (MFP) of the transport medium is longer than the distance between GBs. In addition, due to the miniaturization of modern electronic devices, the size of electronic devices is becoming increasingly smaller, and the demand for two-dimensional (2D) electronic materials, including metals, is increasing. Therefore, the synthesis of single-crystal metals in 2D geometries is an interesting problem. Nucleation in the early growth stage produces countless isolated particles. Although tremendous efforts have been made to minimize GBs in 2D metals, they have not been completely suppressed to date, especially for large-scale noble metals (e.g., Cu and Au) with thicknesses reaching 10 nm. GBs formed in the early growth stage cause electron scattering, resulting in the loss of intrinsic properties. For example, the resistivity of noble metals increases with decreasing thickness, which is noticeable in the 2D limit. Despite the tremendous interest in 2D materials sparked by the discovery of graphene, the 2D properties of novel metals remain largely unexplored. Therefore, thickness control is being pursued to address engineering challenges, such as achieving high conductivity with minimal metal for device fabrication. The primary physical cause of the thickness-dependent resistivity variation is the modified conduction mechanism of metals, along with GB properties. In the absence of GBs and when the thickness is less than the mean free path (MFP) of the transport medium, unconventional transport of the metal can be considered.

[0077]

[0078] On the other hand, in the single crystal copper thin film according to the present invention, the frequency of electrons colliding with GBs is significantly reduced, the mean free path is lengthened, and they sufficiently circle the outermost Fermi surface, so that they behave like holes while circling around hole pockets in the reciprocal lattice space.

[0079] In this study, we demonstrate counterintuitive hole-carrier dominated (HCD) transport in ultraclean 2D copper induced by the combination of the 2D geometry of single-crystal filament (SCCF) films and GB-free growth. GB density can be strongly suppressed in 2D copper fabricated by an atomic sputtering epitaxy (ASE) system. In the absence of grain boundaries, another category of geometrical features, twin boundaries (TBs), can be investigated, which satisfy symmetry compared to GBs and therefore do not interfere with electron transport. A rigorous characterization of the electronic band structure of 2D copper was performed using structural analysis, angle-resolved photoemission spectroscopy (ARPES) measurements, and Hall measurements using two-carrier model fitting analysis. Unlike the electron carriers in conventional copper, the GB suppression in 2D single-crystal filament (SCCF) films indicates hole-carrier dominated (HCD) transport. First-principles theoretical calculations and angle-resolved photoemission spectroscopy (ARPES) measurements experimentally demonstrate HCD transport due to the concave shape of the Fermi surface in 2D copper with zero GBs. The unique properties of the transport suggest a novel approach to manipulating the apparent polarity of charge carriers in metals based on engineering GBs in 2D geometries.

[0080] Figure 2(a) shows the Fermi surface of bulk single crystal copper, and when the bulk (3D) single crystal copper becomes 2D, it shows a pattern similar to Figure 2(b). If copper has an ideal single crystal structure, electrons will circle the outermost surface of Figure 2(b), and when this is represented as a diagram of a periodic reciprocal lattice space, it will look like Figure 3.

[0081] As indicated by the blue circles in Figure 3, electrons orbit in electron orbits, but electrons orbiting the outermost shell exit through open orbits to the adjacent Fermi plane, forming a triangular hole orbit. The theoretical calculation results in Figures 2 and 3 are also experimentally verified.

[0082] Figure 4(a) accurately experimentally represents the theoretical model of 2D single crystal copper predicted in Figure 3. The hexagonal orbit at the bottom of Figure 3(a) represents the electron orbit, and the triangle orbit visible at the right or left shoulder position represents the hole orbit. k along the direction of the orange arrow in Figure 4(a) x The energy distribution in the direction is measured in Fig. 4(b), where the orbit for the electron (blue dotted line) and the orbit for the hole (yellow dotted line) are observed very clearly.

[0083] To understand the unique properties of 2D copper films, we calculated the electronic band structure of copper in the 2D limit. When copper is thinned along the spatial coordinates to the nanometer scale, reaching the 2D limit, quantum confinement reconstructs the typical 3D Fermi surface as shown in Figure 2(a), and the 2D subband surfaces are structured as shown in Figure 2(b). This results in a series of 2D Fermi surfaces. When copper is thinned along the direction, a unique deformation of the 2D Fermi surface leads to the formation of concave electron and hole bands, respectively.

[0084] Due to the neck along the (111) direction on the 3D Fermi surface, a Fermi surface with a shape near the K-point is predicted as shown in Fig. 2(b). The Fermi surface in the center (inner ring) is an electron orbital (scaled by eH / ħc) with higher potential energy and lower Fermi velocity than the outermost surface, and the carriers in these orbitals are electrons. The outermost concave Fermi surface has a negative curvature, resulting in hole carriers. This is because conduction carriers moving along the convex and concave Fermi surfaces are previously observed in YBa2Cu3O. 7-x , La 2-x Sr x CuO4, FeSe, and Ba(Fe 1-x Co x)2As2, as observed in quasi-2D systems such as 2As2, because they contribute to different polarities based on the geometric interpretation of the Fermi surface. As shown in Fig. 3, it becomes somewhat clear in the periodic domain system that the 2D FS consists of electron pockets at the domain center (indicated by blue circles) and hole pockets at the domain edges (indicated by red circles).

[0085] To experimentally confirm the expected Fermi surface reconstruction due to quantum confinement, we directly measured the electronic structure of an 80 nm thick 2D single-crystal film (SCCF), thin enough to reach the 2D limit at low temperatures, using ARPES. As expected, the Fermi surface topology taken for the kz = 0 plane (Fig. 4(a)) contrasts sharply with the well-known Fermi surface topology of 3D Cu (Fig. 2(a)), clearly showing two types: a large hexagonal FS centered at the region center and a triangular FS around the region edges, which closely match the calculated FS topology.

[0086]

[0087] Figure 5 shows a Hall measurement showing how the Hall resistance changes with a magnetic field. Unlike Figure 1, this measurement shows a nonlinear behavior rather than a linear one. This nonlinear behavior becomes more pronounced as the temperature decreases. Furthermore, this nonlinear behavior appears in single-crystal copper films starting from a thickness of 200 nm or less, and is present without exception up to a thickness of 10 nm. In particular, the nonlinearity is most pronounced at a thickness near 40 nm.

[0088] The influence of GBs on hole behavior was investigated using a 40 nm single-crystal copper thin film sample with the most pronounced nonlinearity. The results show that nonlinear behavior is not observed in the sample with GBs, and the nonlinearity is weakened even when a small number of GBs are present, so the observation of hole transporters is very distinct in the 2D copper thin film where GBs have almost disappeared.

[0089] More specifically, to measure the nonlinear Hall effect (NHE) of 2D copper, we directly investigated the HCD transport. The Fermi surface of copper originates from the s-band, which is similar to free electrons, while the fully filled d-electrons do not contribute to the electronic band near the Fermi level. The s-band property of copper is due to its sufficiently high conductivity and a maximum of 1.1×10 6 m / s, which is shown in Fig. 2(a) through color mapping. As shown in Fig. 1, bulk single crystal copper thicker than 1 μm has n = 9.09 × 10 at T = 3 K. 22 cm -3 It shows a typical Hall effect with a single carrier (electron) density of . As shown in Fig. 5(a), even if it is a single crystal, it means that the 3D single crystal copper behaves the same as the polycrystalline copper film (PCCF) in the 2D limit.

[0090]

[0091] Although 3D copper also has a concave Fermi surface, this region is very narrow and does not lead to purely hole-like orbitals in the periodic regime. Therefore, it is difficult to observe hole carriers in bulk copper. However, 2D single-crystal film (SCCF) samples exhibit different behavior in the 2D regime. As shown in Figures 5(b) to 5(f), as the thickness of the 2D single-crystal film (SCCF) sample decreases below 205 nm, the conventional Hall effect, which exhibits a linear response to an external magnetic field, changes to the nonlinear Hall effect (NHE). Here, the nonlinear Hall effect (NHE) exhibits a deviation from the linear dependence on an external magnetic field, called the conventional Hall effect. As shown in Fig. 5(b), the nonlinearity at low temperature starts at a thickness of 205 nm, becomes more pronounced at thicknesses of 80 nm (Fig. 5(c)) and 40 nm (Fig. 5(d)), and is slightly suppressed at thin samples of 12 nm (Fig. 5(e)) and 10 nm (Fig. 5(f)), approaching the limit of thin film growth.

[0092]

[0093] Hereinafter, the present invention will be described in more detail through comparative examples and experimental examples manufactured using conventional methods. The objectives, features, and advantages of the present invention will be readily understood through the following examples. The present invention is not limited to the examples described herein and may be embodied in other forms. The examples introduced herein are provided to ensure that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Therefore, the present invention should not be limited by the following examples.

[0094]

[0095] Example 1: Fabrication of single-crystal copper thin films using ASE technology

[0096] Cu thin films were fabricated using the Advanced Sequencing (ASE) technique to achieve high-quality crystallinity, with GB-free single crystals and GB density-controlled single crystals. The ASE system is a modified RF sputtering system that utilizes a single-crystal sputtering target, replaces the conventional electrical conductor with a single-crystal conductor, and utilizes a mechanical noise reduction (MNR) system. The optimal growth temperature is approximately 170°C, varying by ±10°C depending on the system. To control the GB density, thin films containing 40 nm-thick GBs were grown at 100°C, which is intentionally lower than the optimal temperature, and the number of GBs was controlled through additional heat treatment. The number of GBs and TBs was accurately determined by EBSD mapping using the misorientation line distribution in RD mode. Ar gas (99.9999%, 6N) was used as the deposition atmosphere. The relationship between deposition time and film thickness (or average growth rate) was determined from the average deposition time of a 200 nm-thick film grown under optimal conditions. The determined average growth rate of ~4.3 nm / min is quite reliable for film thicknesses above 10 nm. The initial pressure of RF sputtering is 2.3×10 -3 The operating pressure was controlled by injecting argon gas (99.9999%) up to 0.5 Pa. The RF power was 25 W, and the rotation speed was 30 RPM. The thickness of the film was controlled by the deposition time and confirmed by atomic force microscopy (AFM). The atomic structure of the cross-sectional copper film was observed in annular dark-field (ADF) imaging mode using an aberration-corrected scanning transmission electron microscope (STEM, JEM-ARM200CF, JEOL) operating at 200 kV with a probe forming angle of ~23. The angular range of the ADF detector was set to 45–170 mrad.

[0097]

[0098] Experimental Example 1: Structural Measurement

[0099] EBSD images were obtained using a SUPRA40 VP system (Carl Zeiss AG, Oberkochen, Germany) equipped with a fully automated instrument attachment including an EDAX-TSL Hikari EBSD detector. EBSD maps were acquired using a spatial step size of 80 nm on a hexagonal grid. The area size of a single mapping was approximately 174.3 μm. 2 The average confidence index of the Kikuchi map during EBSD scans was typically between 0.80 and 0.90. However, for polycrystalline Cu films, the index was around 0.7. Misorientation statistics were derived from the EBSD maps using TSL OIM analysis v7 (Ametek, Inc.). If the misorientation was greater than 1°, the segment between two adjacent points was considered a boundary. In the misorientation map, boundaries with misorientation angles between 0 and 59° are indicated by blue lines corresponding to GBs, and boundaries with misorientation angles of 60° are indicated by red lines, which are associated with TBs of the face-centered cubic (FCC)(111) structure.

[0100]

[0101] Experimental Example 2: ARPES Measurement

[0102] High-resolution ARPES measurements were performed at beamline 4.0.3 of the Advanced Light Source (ALS). The Cu films were 5 X 10 -10 Annealed under ultra-high vacuum at pressures exceeding 10 Torr and 5 X 10 -11 Measurements were made at 10 K at pressures exceeding 10 Torr. The overall energy and angular resolution were set to be higher than 20 meV and 0.1°, respectively.

[0103]

[0104] Experimental Example 3: Hall Measurement and Sample Preparation

[0105] Hall bar devices of Cu thin films on sapphire substrates were fabricated by e-beam lithography and wet etching using FeCl3 solution. Typical device channel lengths and widths were 200 μm and 20 μm, respectively. Electrical transport measurements of the Cu thin film devices were performed by a TeslatronPT (Oxford) over the temperature range T=1.5 to 300 K. A magnetic field (up to 12 Tesla) was applied perpendicular to the planar surface. A Keithley 4200 or 6221 current generator was used to apply DC current to the devices, and the longitudinal (for resistivity and magnetoresistance) and transverse (for Hall) voltage differences were simultaneously measured using multiple Keithley 2182A voltmeters. The applied current was on the order of mA.

[0106]

[0107] Experimental Example 4: Comparison of Polycrystalline and Single-Crystal Samples

[0108] To compare polycrystalline and single-crystal samples, polycrystalline thin films with many GBs and single-crystal thin films with different GB concentrations were prepared and compared.

[0109] The first column shows EBSD measurements for a 40 nm thick thin film, the second column shows the misorientation lines measured and the number of GBs and twin boundaries (hereinafter referred to as TB) are shown in a table in the rightmost column, and the third column presents the results of Hall effect measurements for each sample. In addition, (a) shows the results for a GB concentration of 10 2 / ㎛ 2 This is an experimental result for a polycrystalline thin film formed by heat treatment at different temperatures. 1 / ㎛ 2 (b), 10 0 / ㎛ 2 (c), 10 -1 / ㎛ 2 (d) and 0 (e) are single crystal thin films grown by the ASE method by controlling the concentrations.

[0110] Compared to the polycrystalline sample, samples (b) to (d) have significantly reduced GBs, which are perfectly aligned along the (111) direction out of the plane, but some GBs (blue lines in column 2) still exist in the in-plane direction, and the most strongly nonlinear behavior is observed in sample (e), where GBs have completely disappeared. The red lines in column 2 are TBs, and since the two adjacent orientations satisfy the symmetry, they do not significantly affect the electron motion.

[0111]

[0112] By means of solving the above problem, the present invention can solve the defects of general copper, lengthen the mean free path of electrons, and thereby change the structure of the Fermi surface where the existing electrons stay, thereby modifying the orbit of the electrons.

[0113] In addition, the present invention can manufacture a copper thin film that is designed to implement n-type and p-type characteristics using only copper by modifying the copper electron orbit.

[0114]

[0115] In this way, it will be understood by those skilled in the art that the technical configuration of the present invention described above can be implemented in other specific forms without changing the technical idea or essential features of the present invention.

[0116] Therefore, the embodiments described above should be understood as being exemplary and not restrictive in all respects, and the scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. Including a single crystal copper thin film having a thickness of 200 nm or less, The above single crystal copper thin film is characterized by suppressed grain boundaries (GB). Single crystal copper thin film including nonlinear Hall effect and hole carrier dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

2. In paragraph 1, The above single crystal copper thin film is, It is characterized by nonlinear behavior of Hall resistance according to magnetic field. Single crystal copper thin film including nonlinear Hall effect and hole carrier dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

3. In paragraph 1, The above single crystal copper thin film is, Characterized in that copper is grown by atomic sputtering epitaxy (ASE) on a sapphire substrate. Single crystal copper thin film including nonlinear Hall effect and hole carrier dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

4. Including a single crystal copper thin film having a thickness of 200 nm or less, The above single crystal copper thin film has GB suppression, Characterized by electrical properties transformed into p-type, Single crystal copper thin film semiconductor.

5. In paragraph 4, The above single crystal copper thin film is, It is characterized by nonlinear behavior of Hall resistance according to magnetic field. Single crystal copper thin film semiconductor.

6. In paragraph 4, The above single crystal copper thin film is, Characterized in that copper is grown by atomic sputtering epitaxy (ASE) on a sapphire substrate. Single crystal copper thin film semiconductor.

7. Characterized in that it is manufactured by growing a copper thin film by RF sputtering copper at 160 to 180 ℃. A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

8. In paragraph 7, The initial pressure of the above RF sputtering is 2.0×10 -3 2.5×10 -3 characterized by being Pa, A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

9. In paragraph 7, The above RF sputtering is characterized in that it is performed in an Ar gas atmosphere. A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

10. In paragraph 7, The above RF sputtering is characterized in that the pressure is controlled by injecting Ar gas to 0.3 to 0.7 Pa. A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

11. In paragraph 7, The RF output of the above RF sputtering is characterized by being 23 to 27 W. A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

12. In paragraph 7, The rotation speed of the above RF sputtering is characterized by being 25 to 35 RPM. A method for manufacturing a single crystal copper thin film including a nonlinear Hall effect and a hole carrier-dominant transport phenomenon in a two-dimensional single crystal thin film with suppressed grain boundaries.

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