Oxide thin film

Abstract

The present technology relates to an oxide thin film. An oxide thin film according to the present technology comprises: a single crystal substrate; the present invention relates to a thin film transistor including a single crystal substrate, and a main oxide layer laminated on the single crystal substrate and doped with a dissimilar metal element, the dissimilar metal element and a metal element of a metal oxide constituting the main oxide layer being capable of being uniformly distributed in energy-dispersive X-ray analysis (EDX) using a transmission electron microscope (TEM). The present technology can provide an oxide thin film exhibiting MIT characteristics with improved reliability, sensitivity, accuracy, and reproducibility.

Description

Technical Field

[0001] The present invention relates to an oxide film, and more particularly to an oxide film having MIT characteristics. Background Art

[0002] With the advent of the IoT (Internet of Things) era, almost everything has become an electronic device. As a result, various electronic components such as transistors, diodes, memories, sensors, capacitors, etc. have become more powerful and smaller, and more and more electronic components are integrated into electronic devices.

[0003] On the other hand, electronic devices containing more high-performance electronic components may be more susceptible to abnormal internal and external stimuli such as overheating, overcurrent and overvoltage. In order to solve these problems, it is possible to consider integrating a surge protection module into the electronic device.

[0004] From this perspective, interest in semiconductor materials characterized by a metal-insulator transition (MIT) from an insulator to a metal induced by external energy stimulation is growing. Among them, vanadium dioxide (VO 2 ) at ultra-high speed (at fem to (10 -15 ) seconds) shows phase transition at a temperature close to room temperature (about 67°C). Vanadium dioxide (VO 2 ) reacts sensitively and quickly to various energies such as heat, electricity, and light, and therefore has great potential for use in sensing, switching, and especially surge protection applications.

[0005] Single crystal (Single crystal) Bulk (Bulk) VO 2 In the case of phase transition, the structure is deformed and distorted during the phase transition, which leads to rapid destruction within a few cycles. Therefore, single crystal bulk VO 2 There may be limitations in the use of the aforementioned fields. Therefore, in order to ensure the reliability of reproducibility and stability, high-quality VO must be prepared. 2 film.

[0006] In order to make VO 2 The film has the characteristics of high sensitivity and high reliability, VO 2 The resistance difference (R1 / R2) between the metal phase and the insulating phase of the film must be large, and the hysteresis temperature difference (ΔT) which is the difference between the phase transition temperature during temperature increase and the phase transition temperature during cooling must be small. Summary of the invention

[0007] Technical issues to be solved

[0008] Embodiments of the present invention provide an oxide thin film showing MIT characteristics with improved reliability, sensitivity, accuracy, and reproducibility.

[0009] Solutions to the problem

[0010] According to one embodiment, an oxide thin film may include: a single crystal substrate; and a main oxide layer, wherein the main oxide layer is stacked on the single crystal substrate and doped with a heterogeneous metal element, wherein the heterogeneous metal element and the metal elements of the metal oxide constituting the main oxide layer are uniformly distributed in an energy dispersive X-ray analysis (EDX) using a transmission electron microscope (TEM).

[0011] The EDX curve distribution level of the heterogeneous metal element may have a difference within 30% compared with the EDX curve distribution level of the metal element of the metal oxide constituting the main oxide layer.

[0012] A standard deviation of an EDX curve of the dissimilar metal element measured in the thickness direction of the main oxide layer may differ within 30% from a standard deviation of an EDX curve of a metal element of a metal oxide constituting the main oxide layer.

[0013] The main oxide layer may be formed by integrating a crystalline sacrificial layer of the heterogeneous metal element and a pre-oxide thin film formed on the crystalline sacrificial layer through a post-heat treatment process.

[0014] The crystalline sacrificial layer may be grown on the single crystal substrate along a crystal direction of the single crystal substrate.

[0015] The pre-oxide thin film may be a film amorphized on the crystalline sacrificial layer.

[0016] The main oxide layer may be formed by crystallizing the amorphized pre-oxide film in a predetermined direction along the crystallization direction of the crystallization sacrificial layer through the post-heat treatment process.

[0017] The single crystal substrate may be sapphire (Al 2 O 3 ) single crystal substrate, the main oxide layer may be VO 2 At least a portion of the V ions in the crystal lattice are replaced (doped) with Ti ions.

[0018] In addition, the oxide thin film according to an embodiment may include: a single crystal substrate; and VO 2 layer, the VO 2 The layers are stacked on the single crystal substrate and doped with Ti, the VO 2Layer VO 2 The XRD peak does not appear in the range of 2θ=20 to 60°, but may only appear in the range of 2θ=60 to 70°.

[0019] The VO 2 The layer can be defined as a main VO layer with a certain strength above 2θ=20~70°. 2 Multiple XRD peaks appear for high crystallinity epitaxial films rather than polycrystalline films.

[0020] The main VO of the polycrystalline thin film 2 XRD peaks may appear in two or more of the range of 2θ=27.84±0.5°, 2θ=33.4±0.5°, 2θ=37.08±0.5°, 2θ=42.26±0.5°, 2θ=49.52±0.5°, 2θ=55.54±0.5°, 2θ=57.64±0.5°, and 2θ=64.94±0.5°, and the main VO of the epitaxial film 2 The XRD peak can only appear in the range of θ=64.92±0.5°.

[0021] The main VO of the VO2 layer 2 The half width HWHM of the XRD peak may be 1° or less.

[0022] Effects of the Invention

[0023] The present technology can provide an oxide thin film showing MIT characteristics with improved reliability, sensitivity, accuracy, and reproducibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 FIG. 1 is a diagram schematically showing an energy sensing electronic component according to an embodiment of the present invention.

[0025] Figure 2 It is shown along Figure 1 FIG. 1 is a diagram of a cross section along line I-I'.

[0026] Figure 3 It is shown along Figure 1 FIG. 1 is a diagram of a cross section along line II-II'.

[0027] Figure 4 It is enlarged to show Figure 2 Figure of A.

[0028] Figure 5 Graphs showing changes in resistance according to temperature during the first cycle of Example 1 and Experiment 2, respectively.

[0029] Figure 6 is a graph showing the resistance change according to temperature during multiple cycles of Example 1.

[0030] Figure 7 The graph shows the R1 / R2 of Experimental Example 1, the hysteresis temperature difference (ΔT) of Experimental Example 1, and the phase transition temperature (T MI ) are curve graphs of their respective changes.

[0031] Figure 8 FIG. 1 is a diagram showing energy dispersive X-ray analysis (EDX) data of a subject using a transmission electron microscope (TEM) according to an embodiment.

[0032] Fig. 9 It is only enlarged to show Figure 8 Figure 2. EDX curve of Ti.

[0033] Fig.10 It is only enlarged to show Figure 8 Figure 2. EDX curve of V in Figure 2.

[0034] Fig.11 FIG. 1 is a diagram showing XRD (X-ray diffraction) data of a subject according to an embodiment. DETAILED DESCRIPTION

[0035] The terms used in this application are used only to illustrate specific embodiments and are not intended to limit the present invention. Unless otherwise clearly indicated in the context, singular expressions include plural expressions. It should be understood that in this application, terms such as "including" or "having" are only used to specify the existence of features, numbers, steps, actions, constituent elements, parts or combinations thereof recorded in the specification, and do not preclude the existence or additional possibility of one or more other features, numbers, steps, actions, constituent elements, parts or combinations thereof. In addition, throughout the specification, "on..." refers to being located above or below the target portion, and does not necessarily mean being located on the upper side based on the direction of gravity.

[0036] In addition, the word "combined" is used not only as a concept to indicate a contact relationship between constituent elements in which the constituent elements are in direct physical contact with each other, but also as a concept including a situation in which another structure intervenes between the constituent elements and the constituent elements are respectively in contact with another structure.

[0037] Since the size and thickness of each structure shown in the drawings are arbitrarily shown for convenience of explanation, the present invention is not necessarily limited to the contents shown.

[0038] In the figure, the first direction may be defined as an L direction or a length direction, the second direction may be defined as a W direction or a width direction, and the third direction may be defined as a T direction or a thickness direction.

[0039] Hereinafter, a thin film substrate and an energy sensitive electronic component according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals and repeated description thereof will be omitted.

[0040] Various types of electronic components are used in electronic devices for the purpose of preventing overheating or overvoltage, and various types of energy sensing electronic components can be appropriately used between these electronic components. As an example, the energy sensing electronic component can be a thermistor as a heat sensing electronic component, a varistor as an electric energy sensing electronic component, and the like, and can be used to protect various electronic devices, various electronic components of electronic devices, and various electronic component modules.

[0041] In this specification, an energy-sensitive electronic component may refer to an electronic component whose resistance changes with changes in energy such as heat energy, electrical energy, light energy, etc. However, for ease of explanation, the following description will be based on the premise that the resistance of the energy-sensitive electronic component changes with changes in thermal energy, that is, the resistance changes with changes in temperature.

[0042] Figure 1 is a diagram schematically showing an energy sensing electronic component according to an embodiment, Figure 2 It is shown along Figure 1 The cross section of the I-I' line is shown in FIG. Figure 3 It is shown along Figure 1 The cross section of line II-II' is shown in FIG. Figure 4 It is enlarged to show Figure 2 Figure of A.

[0043] Reference Figures 1 to 4 According to an embodiment, an electronic component 1000 includes a film substrate 100, a first external electrode 200, and a second external electrode 300. The film substrate 100 includes a base substrate 110 and a functional film 120. Hereinafter, for convenience of description, the “energy sensing electronic component 1000” is referred to as the “electronic component 1000”.

[0044] The film substrate 100 may constitute the entire appearance of the electronic component 1000 according to the present embodiment. The film substrate 100 may be formed in a hexahedral shape as a whole. Hereinafter, from the viewpoint that the film substrate 100 constitutes the entire appearance of the electronic component 1000 according to the present embodiment, it is referred to as a body 100.

[0045] by Figures 1 to 3 , the main body 100 includes a first surface 101 and a second surface 102 opposite to each other in a first direction 1, a third surface 103 and a fourth surface 104 opposite to each other in a second direction 2, and a fifth surface 105 and a sixth surface 106 opposite to each other in a third direction 3. Each of the first to fourth surfaces 101, 102, 103, 104 of the main body 100 corresponds to a wall surface of the main body 100 connecting the fifth surface 105 and the sixth surface 106 of the main body 100. Hereinafter, two cross sections (one cross section and another cross section) of the main body 100 refer to the first surface 101 and the second surface 102 of the main body 100, two side surfaces (one side surface and another side surface) of the main body 100 refer to the third surface 103 and the fourth surface 104 of the main body 100, and one surface and the other surface of the main body 100 may refer to the sixth surface 106 and the fifth surface 105 of the main body 100, respectively. On the other hand, since the main body 100 includes the base substrate 110 and the functional film 120 disposed on the base substrate 110, each of the first to fourth surfaces 101, 102, 103, and 104 of the main body 100 can be composed of the base substrate 100 and the functional film 120. In addition, the sixth surface 106 of the main body 100 can be basically composed of only the base substrate 100, and the fifth surface 105 of the main body 100 can be basically composed of only the functional film 120. When the electronic component 1000 according to the present embodiment is mounted on a mounting substrate such as a printed circuit board, it can be mounted in a manner that the sixth surface 106 of the main body 100 faces the upper surface of the mounting substrate, or in a manner that the fifth surface 105 of the main body 100 faces the upper surface of the mounting substrate.

[0046] For the main body 100, for example, the electronic component 1000 according to the present embodiment, which is formed with the external electrodes 200 and 300 described later, can be formed to have a length of 7.4 mm and a width of 5.1 mm, a length of 6.3 mm and a width of 3.2 mm, a length of 5.0 mm and a width of 2.5 mm, a length of 4.5 mm and a width of 3.2 mm, a length of 4.5 mm and a width of 1.6 mm, a length of 3.2 mm and a width of 2.5 mm, a length of 3.2 mm and a width of 1.6 mm, a length of 2.5 mm and a width of 2.0 mm, a length of 2.0 mm and a width of 1.2 mm, a length of 1.6 mm and a width of 0.8 mm, a length of 1.0 mm and a width of 0.5 mm, a length of 0.8 mm and a width of 0.4 mm, a length of 0.6 mm and a width of 0.3 mm, and a length of 0.4 mm and a width of 0.2 mm, but is not limited thereto. On the other hand, the aforementioned exemplary values ​​for the length and width of the electronic component 1000 are values ​​that do not reflect process errors, and therefore the values ​​that can be identified as the range of process errors should be considered to correspond to the aforementioned exemplary values. In addition, since the main body 100 of the electronic component 1000 can be formed by forming the functional film 120 on the base substrate 110 in a wafer state and then dicing the base substrate 110 in a wafer state, the length and width of the electronic component 1000 can be substantially the same as the length and width of the base substrate 110 and the length and width of the functional film 120.

[0047] Here, the length of the electronic component 1000 may refer to the maximum value of the dimensions along the first direction 1 of the plurality of line segments connecting two boundary lines opposite to each other in the first direction 1 and parallel to the first direction 1 among the outermost boundary lines of the electronic component 1000 shown in the above photograph, based on the optical microscope or SEM photograph of the cross section (1-3 cross section) of the electronic component 1000 taken from the center of the second direction 2 of the electronic component 1000 along the first direction 1-third direction 3. Alternatively, the length of the electronic component 1000 may refer to the minimum value of the dimensions along the first direction 1 of the plurality of line segments connecting two boundary lines opposite to each other in the first direction 1 and parallel to the first direction 1 among the outermost boundary lines of the electronic component 1000 shown in the above photograph. Alternatively, it may refer to the arithmetic mean of the dimensions along the first direction 1 of at least two of the plurality of line segments connecting two boundary lines opposite to each other in the first direction 1 and parallel to the first direction 1 among the outermost boundary lines of the electronic component 1000 shown in the above photograph.

[0048] Here, the width of the electronic component 1000 may refer to the maximum value of the dimensions along the second direction 2 of the plurality of line segments connecting two boundary lines opposite to each other in the second direction 2 and parallel to the second direction 2 among the outermost boundary lines of the electronic component 1000 shown in the above photograph, based on the optical microscope or SEM photograph of the cross section (1-2 cross section) of the electronic component 1000 taken from the center of the third direction 3 of the electronic component 1000 along the first direction 1-second direction 2. Alternatively, the length of the electronic component 1000 may refer to the minimum value of the dimensions along the second direction 2 of the plurality of line segments connecting two boundary lines opposite to each other in the second direction 2 and parallel to the second direction 2 among the outermost boundary lines of the electronic component 1000 shown in the above photograph. Alternatively, it may refer to the arithmetic mean of the dimensions along the second direction 2 of at least two of the plurality of line segments connecting two boundary lines opposite to each other in the second direction 2 and parallel to the second direction 2 among the outermost boundary lines of the electronic component 1000 shown in the above photograph.

[0049] Here, the thickness of the electronic component 1000 may refer to the maximum value of the dimensions along the third direction 3 of the plurality of line segments connecting two boundary lines opposite to each other in the third direction 3 and parallel to the third direction 3 among the outermost boundary lines of the electronic component 1000 shown in the above photograph, based on the optical microscope or SEM photograph of the cross section (1-3 cross section) of the electronic component 1000 taken along the first direction 1-third direction 3 from the center of the second direction 2 of the electronic component 1000. Alternatively, the length of the electronic component 1000 may refer to the minimum value of the dimensions along the third direction 3 of the plurality of line segments connecting two boundary lines opposite to each other in the third direction 3 and parallel to the third direction 3 among the outermost boundary lines of the electronic component 1000 shown in the above photograph. Alternatively, it may refer to the arithmetic mean of the dimensions along the third direction 3 of at least two of the plurality of line segments connecting two boundary lines opposite to each other in the third direction 3 and parallel to the third direction 3 among the outermost boundary lines of the electronic component 1000 shown in the above photograph.

[0050] Alternatively, each of the length, width, and thickness of the electronic component 1000 can be measured by a micrometer measurement method. In the micrometer measurement method, the electronic component 1000 according to the present embodiment can be measured by setting a zero point of a micrometer having Gage R&R (Repeatability and Reproducibility), inserting the electronic component 1000 between the tips of the micrometer, and rotating the lever of the micrometer. On the other hand, when the length of the electronic component 1000 is measured using the micrometer measurement method, the length of the electronic component 1000 can represent a value measured once, or can represent an arithmetic average of values ​​measured multiple times. The same can also be applied to the width and thickness of the electronic component 1000.

[0051] The main body 100 includes a base substrate 110 and a functional film 120. Specifically, the main body 100 includes a substrate 110 and a surface (with a Figures 1 to 3 The functional film 120 is formed on the upper surface of the substrate 110 with the direction of the substrate 110 as the reference.

[0052] The base substrate 110 may be a single crystal substrate. The base substrate 110 may be grown in one direction to have crystallinity. For example, the base substrate 110 may be Al 2 O 3 Single crystal substrate, Si single crystal substrate, SiC single crystal substrate, Ge single crystal substrate, TiO 2 Single crystal substrate, ZnO single crystal substrate, ZnS single crystal substrate, ZnSe single crystal substrate, ZnTe single crystal substrate, CdS single crystal substrate, CdSe single crystal substrate, Cd Te single crystal substrate, GaAs single crystal substrate, GaP single crystal substrate, GaSb single crystal substrate, InAs single crystal substrate, InP single crystal substrate, SrTiO 3 Single crystal substrate, or MgO single crystal substrate.

[0053] The functional film 120 may be VO doped with Ti. 2 film.

[0054] As a non-limiting example, the functional thin film 120 may be formed by forming a TiO layer on the base substrate 110. 2 Sacrificial layer, forming VO on the sacrificial layer 2 The main oxide film layer is formed on the base substrate 110 by post-heat treating the sacrificial layer and the main oxide film layer.

[0055] Here, the sacrificial layer may be grown on the base substrate 110 in a certain direction along the crystallization direction of the base substrate 110. That is, the sacrificial layer may be pre-crystallized before forming the main oxide thin film layer. The thickness of the sacrificial layer may be, for example, 1 nm to 50 nm, but the scope of the present invention is not limited thereto, and may be appropriately changed according to the designed Ti ion concentration on the functional film 120. For example, the sacrificial layer may be formed by a thin film process such as physical vapor deposition (PECVD) such as sputtering, pulsed laser deposition (PLD), electron beam evaporator (e-beam evaporator), chemical vapor deposition (PECVD, MOCVD), atomic film deposition (ALD) and molecular beam epitaxy (MBE).

[0056] Here, the main oxide film layer can be a film that is crystallized or amorphized in a certain direction along the crystallization direction of the sacrificial layer on the sacrificial layer. When a subsequent heat treatment process is performed after the main oxide film layer is formed, the main oxide film layer can be formed on the sacrificial layer in an amorphous state. The thickness of the main oxide film layer can be, for example, 10nm to 1000nm, but the scope of the present invention is not limited thereto, and can be appropriately changed according to the Ti ion concentration on the designed functional film 120. For example, the main oxide film layer can be formed by a thin film process such as physical vapor deposition (PECVD) such as sputtering, pulsed laser deposition (PLD), electron beam evaporator (e-beam evaporator), chemical vapor deposition (PECVD, MOCVD), atomic film deposition (ALD) and molecular beam epitaxy (MBE).

[0057] Here, the post-heat treatment may be a process for integrating the sacrificial layer and the main oxide film layer. Specifically, the post-heat treatment may be an integrated process for doping the substance constituting the sacrificial layer into the main oxide film layer to eliminate the boundary between the sacrificial layer and the main oxide film layer. The post-heat treatment may be performed using equipment such as a box furnace, a tube furnace, or a rapid thermal processing furnace (RTA). The post-heat treatment may be performed in an atmosphere such as air, oxygen, or a mixture of air and oxygen. 2 ), nitrogen (N 2 ), argon (Ar) and hydrogen (H 2 ) in one or more atmospheres. The post-heat treatment may be performed, for example, at a temperature range of 400° C. to 800° C. This is a method of depositing the main oxide layer at a low temperature and performing the post-heat treatment, which is beneficial to the construction of the vacuum equipment chamber and is advantageous in terms of film reproducibility by reducing the variables caused by temperature in the deposition.

[0058] The crystal structure and direction of the functional film 120 formed by the post-heat treatment process can be determined based on, for example, the crystal structure and direction of the sacrificial layer. For example, the functional film 120 integrated by post-heat treatment of the sacrificial layer and the main oxide film layer can be crystallized in a certain direction along the crystallization direction of the sacrificial layer before the post-heat treatment. At this time, the crystallization directions of the functional film 120 and the sacrificial layer are not necessarily the same. For example, the functional film 120 can have a lattice spacing substantially the same as that of the sacrificial layer, but grows and crystallizes in a direction different from the direction of the crystallized sacrificial layer. In addition, since the metal ion radius of the sacrificial layer is similar to the metal ion radius of the main oxide film layer (Ti 4+ The ionic radius is V 4+ The ionic radius is ), so the metal ions of the sacrificial layer will not substantially change the VO 2 The crystal structure enables self-diffusion.

[0059] That is, the lattice difference between the sacrificial layer and the main oxide layer at the bonding surface can be less than 1%, and the difference between the metal ion radius of the sacrificial layer and the metal ion radius of the main oxide layer can be less than 5%. This is to allow the metal ions to self-diffuse without crystal structure deformation during the post-heat treatment process.

[0060] When the resistance of the functional film 120 at 25° C. is referred to as R1 and the resistance at 80° C. is referred to as R2, R1 / R2 may be 10 4 The R1 / R2 of the functional film 120 may be, for example, 17000 or more. By achieving the R1 / R2 of the functional film 120 to be 10 4 As described above, the electronic component 1000 according to the present embodiment can more sensitively sense energy changes within a temperature range of 25° C. to 80° C.

[0061] When the temperature increase process from 25°C to 80°C and the cooling process from 80°C to 25°C are referred to as one cycle, the functional film 120 may satisfy at least one of the following: a) a change in the hysteresis temperature difference (ΔT) during ten cycles (V △T ) is below 1°C, b) the phase transition temperature (T MI ) changes (V TMI ) is below 1.5°C, and c) the rate of change of R1 / R2 during ten cycles (V R1 / R2 ) is less than 5%.

[0062] Here, the hysteresis temperature difference (ΔT) of the functional film 120 may refer to the temperature at which the absolute value of the temperature coefficient of resistance (TCR) of the functional film 120 defined by the following formula 1 during the heating process is the maximum, based on one cycle. H The temperature at which the absolute value of the temperature coefficient of resistance (TCR) of the functional film 120 defined by the following formula 1 is the maximum during the cooling process is set as T C When T H and T C The difference between. The hysteresis temperature difference (△T) of the functional film 120 can be 1°C or less, for example, can be 0.726°C or less. When the hysteresis temperature difference (△T) of the functional film 120 is 1°C or less, the functional film 120 can be regarded as having substantially no thermal hysteresis during the cycle. As a result, within the temperature range of the above-mentioned heating and cooling processes, for the same resistance, the temperature of the functional film 120 during the heating process and the temperature during the cooling process can be substantially the same. Therefore, the electronic component 1000 according to the present embodiment is different from conventional electronic components in which the temperature of the same resistance changes depending on whether it is in the heating process or the cooling process, and can sense energy changes relatively accurately.

[0063] [Formula 1]

[0064] TCR( / ℃)=-(1 / R)*(dR / dT)

[0065] In addition, during the ten cycles of the functional film 120, the change in the hysteresis temperature difference (ΔT) (V △T ) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the difference (V) between the maximum value and the minimum value of the hysteresis temperature difference (ΔT1, ΔT2, ..., ΔT10) of the functional film 120 obtained in the first cycle to the tenth cycle, respectively. △T =│△T1,△T2,…,△T10)-Min(△T1,△T2,…,△T10)│). Alternatively, during ten cycles of the functional film 120, the change in the hysteresis temperature difference (△T) (V △T ) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the difference (VΔT=|ΔT1-ΔT10|) between the hysteresis temperature difference (ΔT1) of the functional film 120 in the first cycle and the hysteresis temperature difference (ΔT10) of the functional film 120 in the tenth cycle. When the change (VΔT) of the hysteresis temperature difference (ΔT) of the functional film 120 during ten cycles is △T) is 1°C or less, the functional film 120 can be regarded as having a substantially constant hysteresis temperature difference (ΔT) even if the cycle increases. As a result, the functional film 120 can repeatedly, stably, and accurately sense energy changes within the temperature range of the above-mentioned heating and cooling processes. Therefore, the electronic component 1000 according to the present embodiment can improve the repeatability of accuracy.

[0066] Here, the phase transition temperature (T MI ) can be defined by the following formula 2. That is, the phase transition temperature (T MI ) can refer to a cycle T H With T C The phase transition temperature (T MI ) may be below 54° C., for example, 52.4° C., 53.1° C., or 53.5° C., but the scope of the present invention is not limited thereto. Specifically, the phase transition temperature (T MI ) can be changed by the content of Ti ions doped in the functional film 120. When the phase transition temperature (T MI ) is 54° C. or less, the Metal-Insulator Transition (MIT) phenomenon can be utilized in a relatively low temperature region. Therefore, the electronic component 1000 according to the present embodiment can be used as a switch component in a relatively low temperature region.

[0067] [Formula 2]

[0068] T MI (C)= / T H -T C / / 2

[0069] In addition, during the ten cycles of the functional film 120, the phase transition temperature (T MI ) changes (V TMI ) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the phase transition temperature (T MI1 ,T MI2 ,…,T MI10 ) between the maximum and minimum values ​​(V TMI =│ MI1 ,T MI2 ,…,T MI10 )-Min(TMI1,T MI2 ,…,T MI10 Alternatively, during ten cycles of the functional film 120, the phase transition temperature (T MI ) changes (V TMI) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the phase transition temperature (T MI1 ) and the phase transition temperature (T MI10 ) between (V TMI =│ MI1 -T MI10 │). When the functional film 120 has a phase transition temperature (T MI ) changes (V TMI ) is 1.5° C. or less, the functional film 120 can be regarded as having a substantially constant phase transition temperature (T MI As a result, the functional film 120 can repeatedly and stably realize the switching function within the temperature range of the above-mentioned heating and cooling processes. Therefore, the electronic component 1000 according to this embodiment can be repeatedly used as a switching component in a relatively low temperature region regardless of the number of operations.

[0070] Here, during ten cycles of the functional film 120, the change rate of R1 / R2 (V R1 / R2 ) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the R1 / R2 values ​​((R1 / R2)) of the functional film 120 respectively obtained in the first cycle to the tenth cycle. 1 ,(R1 / R2) 2 …,(R1 / R2) 10 ) divided by the percentage of the maximum value (V R1 / R2 =100*(│) 1 ,(R1 / R2) 2 …,(R1 / R2) 10 )-Min((R1 / R2) 1 ,(R1 / R2) 2 …,(R1 / R2) 10 )│) / Max((R1 / R2) 1 ,(R1 / R2) 2 …,(R1 / R2) 10 )). Alternatively, during ten cycles of the functional film 120, the change rate of R1 / R2 (V R1 / R2 ) may refer to, for example, when the functional film 120 is subjected to a temperature increase process and a cooling process from the first cycle to the tenth cycle, the R1 / R2 value ((R1 / R2)) of the functional film 120 in the first cycle 1 ) and the R1 / R2 value of the functional film 120 in the tenth cycle ((R1 / R2) 10) relative to the R1 / R2 value ((R1 / R2)) of the functional film 120 in the first cycle 1 ) percentage (V R1 / R2 =100*(│ 1 -(R1 / R2) 10 │) / (R1 / R2) 1 ). When the change rate of R1 / R2 during ten cycles of the functional film 120 is V R1 / R2 When the ratio of the R1 / R2 of the functional film 120 to the energy change is 5% or less, the functional film 120 can be regarded as having a substantially constant value of R1 / R2 even if the cycle increases. As a result, the functional film 120 can repeatedly and stably and sensitively sense energy changes within the temperature range of the above-mentioned heating and cooling processes. Therefore, the electronic component 1000 according to the present embodiment can improve the reproducibility of sensitivity.

[0071] The external electrodes 200 and 300 are arranged on the main body 100 in a spaced manner. That is, the external electrodes 200 and 300 are arranged on the base substrate 110 and / or the functional film 120 in a spaced manner. Each of the external electrodes 200 and 300 is in contact with the functional film 120. The external electrodes 200 and 300 can be formed by at least one of a vapor deposition method such as sputtering, an electroplating method, and a method of curing after coating a conductive paste. The external electrodes 200 and 300 may include conductive materials such as platinum (Pt), gold (Au), chromium (Cr), molybdenum (Mo), nickel (Ni), titanium (Ti), silver (Ag), aluminum (Al), copper (Cu), iron (Fe), indium (In), tin (Sn), lead (Pb), palladium (Pd), zinc (Zn) and cobalt (Co) or their alloys. The external electrodes 200 and 300 can be formed as a single layer or a multilayer structure.

[0072] The external electrodes 200 and 300 include conductive resin layers 210 and 310 and metal layers 220 and 320 formed on the conductive resin layers 210 and 310. Specifically, the first external electrode 200 includes a first conductive resin layer 210 formed on the body 100 and a first metal layer 220 formed on the first conductive resin layer 210. The second external electrode 300 includes a second conductive resin layer 310 and a second conductive resin layer 320 formed on the body 100.

[0073] The first conductive resin layer 210 is disposed on the first surface 101 of the main body 100 and extends to at least a portion of each of the third to sixth surfaces 103, 104, 105, 106 of the main body 100. The first conductive resin layer 210 is in contact with one end of the functional film 120 on the first surface 101 side of the main body 100. The second conductive resin layer 310 is disposed on the second surface 102 of the main body 100 and extends to at least a portion of each of the third to sixth surfaces 103, 104, 105, 106 of the main body 100. The second conductive resin layer 310 is in contact with the other end of the functional film 120 on the second surface 102 side of the main body 100. The first conductive resin layer and the second conductive resin layer 210, 310 are respectively disposed on the third to sixth surfaces 103, 104, 105, 106 of the main body 100, spaced apart from each other. On the other hand, Figures 1 to 3 , the conductive resin layers 210 and 310 are respectively shown as normal types formed on five surfaces of the main body 100, but this is only exemplary. That is, according to the design, each of the conductive resin layers 210 and 310 can be deformed into one of a C type (for example, the first conductive resin layer 210 is only configured on the first surface 101, the fifth surface 105, and the sixth surface 106 of the main body 100), an L type (for example, the first conductive resin layer 210 is only configured on the first surface 101 and the fifth surface 105 of the main body 100, or only configured on the first surface 101 and the sixth surface 106 of the main body 100) and a bottom electrode type (for example, the first conductive resin layer 210 is only configured on the fifth surface 105 of the main body 100).

[0074] The conductive resin layers 210 and 310 include a base resin R and conductive particles CP dispersed in the base resin R. The conductive particles CP may contact and connect to each other in the base resin R to connect the external electrodes 200 and 300 and the functional film 120 to each other. The conductive resin layers 210 and 310 may be formed by applying a conductive paste for forming a conductive resin layer to the body 100 and curing the conductive paste.

[0075] The base resin R may include a thermosetting resin having electrical insulation properties. The thermosetting resin may be, for example, an epoxy resin, but the present invention is not limited thereto.

[0076] The conductive particles CP may include at least one of platinum (Pt), gold (Au), chromium (Cr), molybdenum (Mo), nickel (Ni), titanium (Ti), silver (Ag), aluminum (Al), copper (Cu), iron (Fe), indium (In), tin (Sn), lead (Pb), palladium (Pd), zinc (Zn) and cobalt (Co). As a non-limiting example, the conductive particles CP may include at least one of platinum (Pt) particles, gold (Au) particles, chromium (Cr) particles, molybdenum (Mo) particles, nickel (Ni) particles, titanium (Ti) particles, silver (Ag) particles, aluminum (Al) particles, copper (Cu) particles, iron (Fe) particles, indium (In) particles, tin (Sn) particles, lead (Pb) particles, palladium (Pd) particles, zinc (Zn) particles, cobalt (Co) particles and alloy particles composed of at least two of the above metals. As another example, the conductive particles CP may be a core-shell structure. Among them, the core may include at least one of platinum (Pt), gold (Au), chromium (Cr), molybdenum (Mo), nickel (Ni), titanium (Ti), silver (Ag), aluminum (Al), copper (Cu), iron (Fe), indium (In), tin (Sn), lead (Pb), palladium (Pd), zinc (Zn) and cobalt (Co), and the shell may include at least one of platinum (Pt), gold (Au), chromium (Cr), molybdenum (Mo), nickel (Ni), titanium (Ti), silver (Ag), aluminum (Al), copper (Cu), iron (Fe), indium (In), tin (Sn), lead (Pb), palladium (Pd), zinc (Zn) and cobalt (Co).

[0077] The conductive particles CP may be spherical and / or flake-shaped. Flake-shaped may mean that the dimension along the first direction to one of the third directions 1, 2, and 3 is 1.5 times greater than the dimension along the first direction to the other of the third directions 1, 2, and 3. Here, the direction of the larger of the two dimensions may be defined as the major axis, and the direction of the smaller one may be defined as the minor axis.

[0078] The metal layers 220 and 320 may be formed on the conductive resin layers 210 and 310. At least a portion of each of the metal layers 220 and 320 is arranged in a region formed on the mounting surface of the electronic component 1000 according to the present embodiment in the conductive resin layers 210 and 320.

[0079] For example, when the mounting surface of the electronic component 1000 according to the present embodiment is the fifth surface 105 side of the body 100, the first metal layer 220 may be formed in the region of the first conductive resin layer 210 disposed on the fifth surface 105 of the body 100, and the second metal layer 320 may be formed in the region of the second conductive resin layer 310 disposed on the fifth surface 105 of the body 100. In this case, the first metal layer 220 may be formed on at least a portion of the first surface 101, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100. Alternatively, even if the first conductive resin layer 210 is formed to extend to the first surface 101, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100, respectively, the first metal layer 220 may not be formed on at least a portion of the first surface 101, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100. At this time, the second metal layer 320 may be formed on at least a portion of the second surface 102, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100. Alternatively, even if the second conductive resin layer 310 is extended to the second surface 102, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100, respectively, the second metal layer 320 may not be formed on at least a portion of the second surface 102, the third surface 103, the fourth surface 104, and the sixth surface 106 of the body 100.

[0080] As another example, when the mounting surface of the electronic component 1000 according to the present embodiment is the sixth surface 106 side of the body 100, the first metal layer 220 may be formed in a region of the first conductive resin layer 210 disposed on the sixth surface 106 of the body 100, and the second metal layer 320 may be formed in a region of the second conductive resin layer 310 disposed on the sixth surface 106 of the body 100. In this case, the first metal layer 220 may be formed on at least a portion of the first surface 101 and the third to fifth surfaces 103, 104, 105 of the body 100. Alternatively, even if the first conductive resin layer 210 is formed to extend to the first surface 101 and the third to fifth surfaces 103, 104, 105 of the body 100, respectively, the first metal layer 220 may not be formed on at least a portion of the first surface 101 and the third to fifth surfaces 103, 104, 105 of the body 100. At this time, the second metal layer 320 may be formed on at least a portion of the second to fifth surfaces 102, 103, 104, 105 of the body 100. Alternatively, even if the second conductive resin layer 310 is extended to the second to fifth surfaces 102, 103, 104, 105 of the body 100, the second metal layer 320 may not be formed on at least a portion of the second to fifth surfaces 102, 103, 104, 105 of the body 100.

[0081] Each of the metal layers 220, 320 may include at least one of platinum (Pt), gold (Au), chromium (Cr), molybdenum (Mo), nickel (Ni), titanium (Ti), silver (Ag), aluminum (Al), copper (Cu), iron (Fe), indium (In), tin (Sn), lead (Pb), palladium (Pd), zinc (Zn) and cobalt (Co).

[0082] Each of the metal layers 220, 320 may be formed as a single layer or multiple layers. The metal layers 220, 320 may be formed by at least one of a deposition method such as sputtering and an electroplating method. As a non-limiting example, each of the metal layers 220, 320 may include a first plating layer 221, 321 formed on the conductive resin layer 210, 310 and a second plating layer 222, 322 formed on the first plating layer 221, 321. As a non-limiting example, the first plating layer 221, 321 may be a nickel plating layer, and the second plating layer 222, 322 may be a tin plating layer. On the other hand, in the case where the area formed by the conductive resin layer 210, 310 and the area formed by the metal layer 220, 320 on the first to sixth surfaces 101, 102, 103, 104, 105, 106 of the main body 100 are different from each other, for example, a process of forming an anti-etching agent that only exposes a portion of the outer surface of the conductive resin layer 210, 310 can be added between the process of forming the conductive resin layer 210, 310 and the process of forming the metal layer 220, 320.

[0083] Experimental example

[0084] (Preparation method of Experimental Examples 1 and 2)

[0085] Experimental Example 1 was prepared by the following method. First, a sapphire (Al 2 O 3 ) TiO is formed on a single crystal substrate 2 A thin film (3nm to 5nm thick) is used as a sacrificial layer. Then, VO is formed on the sacrificial layer by sputtering. 2 A thin film (thickness of 200 to 300 nm) is used as the main oxide film layer. 2 The film is deposited by setting the process temperature to room temperature, the process pressure to 10-30 mtorr, and supplying Ar gas. Then, the sacrificial layer and the main oxide film layer are post-heat treated at 400-800°C to prepare VO 2 A functional thin film in which at least a portion of V ions in the crystal lattice are replaced (doped) with Ti ions. Hereinafter, the thin film (functional thin film) finally prepared according to Experimental Example 1 is referred to as a first thin film.

[0086] Compared with Experimental Example 1, Experimental Example 2 was prepared in the same manner as Experimental Example 1 except that the sacrificial layer of Experimental Example 1 was not deposited. That is, the sapphire (Al 2 O 3 The main oxide thin film layer (VO) is directly formed on the single crystal substrate under the same conditions as those of the main oxide thin film layer in Experimental Example 1. 2 ), and then the main oxide thin film layer is post-heat treated under the same conditions as the post-heat treatment conditions of Experimental Example 1. Hereinafter, the thin film finally prepared according to Experimental Example 2 (the main oxide thin film layer after the heat treatment) is referred to as the second thin film.

[0087] (Evaluation of the first and second film characteristics of thermal cycles)

[0088] A thermal cycle consisting of a temperature increase process from 25° C. to 80° C. and a cooling process from 80° C. to 25° C. was performed multiple times on the first film and the second film, respectively, and the resistance of each of the first film and the second film according to temperature was measured.

[0089] The heating and cooling of the first film and the second film are achieved by installing a heater capable of generating heat at the bottom of the sapphire substrate on which the first film and the second film are formed, respectively, and adjusting the power applied to the heater. Specifically, the first film and the second film are heated by supplying power to the heater at room temperature (25°C), and when the first film and the second film reach 80°C, the power of the heater is cut off to cool the first film and the second film.

[0090] The surface temperatures of the first film and the second film were measured by attaching a contact temperature measuring probe (k-type thermocouple; 0.005 inches thermocouple wire) from Omega Corporation to the first film and the second film and using a nanovoltmeter (model name: Keithley 2182A) from Keithley Corporation.

[0091] The resistance of the first film and the second film is derived by using a product of Keithley (model name: Keithley 2400) as a source meter, applying a constant voltage to the first film and the second film, measuring the current of each of the first film and the second film under the voltage, and then converting it into resistance (R = V / I). At this time, in order to reduce the contact resistance between each of the first film and the second film and the metal probe for measuring the current, a metal film with a thickness of 100 nm is formed on a part of the first film and the second film, and the metal film is brought into contact with the metal probe to measure the current.

[0092] Figure 5 The resistance of the first film and the second film during the first cycle of each film according to the temperature change is shown. Figure 5 In the figure, the first film is represented by "o" and the second film is represented by "△". Figure 6 The resistance of the first film as a function of temperature during multiple cycles is shown. Figure 7 is a curve graph, where the X-axis is the number of thermal cycles, and the Y-axis is the R1 / R2, hysteresis temperature difference (△T) and phase transition temperature (T MI ).exist Figure 7 In the figure, “□” represents R1 / R2, “X” represents the hysteresis temperature difference (△T, unit ℃), and “●” represents the phase change temperature (T MI , unit ℃).

[0093] In Table 1, based on Figure 5 , records the resistance R1 of the first film and the second film at 25°C, the resistance R2 at 80°C, and the temperature T at which the absolute value of the temperature coefficient of resistance (TCR) is the largest during the heating process. H , the temperature T at which the absolute value of the temperature coefficient of resistance (TCR) is the largest during the cooling process C , R1 / R2, hysteresis temperature difference (△T) and phase change temperature (T MI ).

[0094]

Table 1

[0095] R1(Ω) R2(Ω) <![CDATA[T H (℃)]]> <![CDATA[T C (℃)]]> R1 / R2 △T(℃) <![CDATA[T MI (℃)]]> #1 <![CDATA[5.257*10 5 ]]> <![CDATA[2.631*10 2 ]]> 52.427 52.370 19981 0.043 52.40 #2 <![CDATA[1.013*10 6 ]]> <![CDATA[4.653*10 2 ]]> 70.445 59.035 21778 11.41 64.74

[0096] Referring to Table 1, the R1 / R2 of the first film and the second film are 19981 and 21778, respectively, which is 10 4 or above. Considering that the ratio of the resistance of a conventional temperature-sensitive resistor layer at 25°C to that at 80°C is several tens to several hundreds, this means that the resistance change of the first film and the second film in the same temperature range is relatively large compared to the resistance change of the conventional temperature-sensitive resistor layer. Therefore, compared with electronic components using conventional temperature-sensitive resistor layers, electronic components using the first film and the second film can sense temperature more sensitively. Referring to Table 1, the hysteresis temperature difference (△T) of the second film is 11.41°C, and the hysteresis temperature difference (△T) exceeds 1°C. The hysteresis temperature difference (△T) of the first film is 0.043°C, and the hysteresis temperature difference (△T) is less than 1°C. This means that for the same resistance, the difference between the temperature during the heating process and the temperature during the cooling process is relatively large for the second film, and relatively small for the first film. Therefore, compared with electronic components using the second film, electronic components using the first film can sense temperature more accurately. Referring to Table 1 and Figure 5, it can be seen that the maximum value of the temperature coefficient of resistance (TCR) of the first film is greater than the maximum value of the temperature coefficient of resistance (TCR) of the second film, which means that the resistance change of the first film according to the temperature change is greater than that of the second film. Therefore, at the phase transition temperature (T MI ) can be more sensitive to temperature changes near the phase transition temperature (T MI ) to temperature changes around.

[0097] Referring to Table 1, the phase transition temperature (T MI ) is relatively lower than the phase transition temperature (T MI ). This means that the first film changes from a non-conductor to a conductor (Metal-Insulator Transition) at a relatively low temperature compared to the second film. Therefore, the electronic component using the first film can be used as a switch component at a relatively low temperature compared to the electronic component using the second film.

[0098] In Table 2, based on Figure 6 and Figure 7 , and recorded the R1 / R2, hysteresis temperature difference (△T) and phase transition temperature (T MI ), the change of hysteresis temperature difference (△T) during ten cycles (V △T ), phase transition temperature during ten cycles (T MI ) changes (V TMI ) and the rate of change of R1 / R2 during ten cycles (V R1 / R2 ).

[0099] 101 On the other hand, in Table 2, the changes in the hysteresis temperature difference (△T) during ten cycles (V △T ) means, for example, the difference (V) between the hysteresis temperature difference (ΔT) of the first cycle, which is the first cycle of the interval, and the hysteresis temperature difference (ΔT) of the tenth cycle, which is the last cycle of the interval, based on the interval from the first cycle to the tenth cycle. △T =|ΔT1-ΔT10|). The same is true for the phase transition temperature (T MI ) changes (V TMI In addition, in Table 2, the change rate of R1 / R2 during ten cycles (V R1 / R2 ) means, for example, the R1 / R2 value of the first cycle ((R1 / R2)) of the first cycle as the first cycle of the interval from the first cycle to the tenth cycle as a reference. 1 ) and the R1 / R2 value of the tenth cycle, which is the last cycle of the interval ((R1 / R2) 10 ) relative to the R1 / R2 value of the first cycle as the initial cycle of the interval ((R1 / R2)1 ) percentage (V R1 / R2 =100*(|(R1 / R2) 1 -(R1 / R2) 10 |) / (R1 / R2) 1 ).

[0100] In addition, in the following description of Table 2, the first to tenth cycles are described as the first interval, the eleventh to twentieth cycles are described as the second interval, the twenty-first to thirtieth cycles are described as the third interval, the thirty-first to fortieth cycles are described as the fourth interval, and the forty-first to fiftieth cycles are described as the fifth interval.

[0101]

Table 2

[0102] R1 / R2 △T(℃) <![CDATA[T M (℃)]]> <![CDATA[V △T (℃)]]> <![CDATA[V TMI (℃)]]> <![CDATA[V R1 / R2 (%)]]> First 19981 0.043 52.40 - - - tenth 19849 0.347 52.54 0.304 0.14 0.66 eleventh 19754 0.349 52.50 - - - 20th 19811 0.100 52.70 0.249 0.249 0.29 Twenty-first 19798 0.162 52.32 - - - 30th 19706 0.492 52.75 0.330 0.43 0.46 Thirty-first 19620 0.569 52.15 - - - No.40 19785 0.372 52.71 0.197 0.56 0.84 No. 41 19906 0.220 52.53 - - - No.50 19650 0.456 53.13 0.236 0.60 1.28 No. 100 19714 0.636 53.46 - - -

[0103] Referring to Table 2, the change in hysteresis temperature difference (ΔT) (V △T ) is 0.304°C in the case of the first interval, 0.249°C in the case of the second interval, 0.330°C in the case of the third interval, 0.197°C in the case of the fourth interval, and 0.236°C in the case of the fifth interval. That is, the change (V △T ) is below 1°C, and thus can be considered to have a substantially constant hysteresis temperature difference (ΔT), regardless of which interval. As a result, within the temperature range of the above-mentioned heating and cooling processes, the first film can repeatedly, stably, and accurately sense energy changes. Referring to Table 2, during the ten cycles of the first film, the phase transition temperature (T MI ) changes (V TMI ) is 0.14°C in the case of the first interval, 0.249°C in the case of the second interval, 0.43°C in the case of the third interval, 0.56°C in the case of the fourth interval, and 0.60°C in the case of the fifth interval. That is, the phase transition temperature (T) of the first film during all ten cycles from the first interval to the fifth interval is MI ) changes (V TMI ) is below 1.5°C and can therefore be considered to have a substantially constant phase transition temperature (T MI ), regardless of which interval. As a result, within the temperature range of the above-mentioned heating and cooling process, the first film can repeatedly and stably perform the switching function at substantially the same temperature. Referring to Table 2, during the ten cycles of the first film, the change rate of R1 / R2 (V R1 / R2) is 0.66% in the first interval, 0.29% in the second interval, 0.46% in the third interval, 0.84% ​​in the fourth interval, and 1.28% in the fifth interval. That is, the change rate of R1 / R2 (V R1 / R2 ) is less than 5%, so it can be considered to have a substantially constant R1 / R2 value regardless of which interval. As a result, within the temperature range of the above-mentioned heating and cooling process, the first film 120 can repeatedly, stably and sensitively sense energy changes. On the other hand, the above describes the change rate (V) of R1 / R2 during ten cycles of the first film based on the first to fifth intervals, that is, the first cycle to the fiftieth cycle. R1 / R2 ), the change of the hysteresis temperature difference (ΔT) during the ten cycles of the first film (V △T ), and the phase transition temperature (T MI ) changes (V TMI ), but this is only exemplary, and the scope of the present invention is not limited to the foregoing. Figure 7 It can be seen that as long as it is within the first cycle to the fiftieth cycle, the first film has the change rate of R1 / R2 during the ten cycles (V R1 / R2 ), the change of hysteresis temperature difference (△T) during ten cycles (V △T ), and the phase transition temperature during ten cycles (T MI ) changes (V TMI ). In addition, refer to Figure 7 It can be seen that even in the cycle after the 50th cycle, the first film has the change rate of R1 / R2 during the previous ten cycles (V R1 / R2 ), the change of hysteresis temperature difference (△T) during ten cycles (V △T ), and the phase transition temperature during ten cycles (T MI ) changes (V TMI ).

[0104] (Example of experimental data analysis on doping uniformity in functional thin films)

[0105] Figure 8Energy dispersive X-ray analysis (EDX) data of a body using a transmission electron microscope (TEM) according to one embodiment are shown. (a) is data that visualizes the mapping results for V, (b) is data that visualizes the mapping results for Ti, and (c) is an EDX graph that shows the mapping results for each component (Al, V, Ti) with brightness (intensity) as the horizontal axis and sample depth as the vertical axis. In the figure, depth is the ratio of the thickness of the body, a depth value of 0 can be close to the surface of the body, and a depth value of 140 can be close to the bottom surface of the body. For example, the depth range of 0 to 90 nm in the figure can correspond to the above-mentioned functional film, and the depth range of 90 to 140 nm in the figure can correspond to the above-mentioned base substrate. As described above, the base substrate is sapphire (Al 2 O 3 ) Single crystal substrate, functional film is VO 2 At least a portion of the V ions in the crystal lattice are replaced (doped) with Ti ions.

[0106] As shown in the figure, it can be confirmed that Ti is uniformly dispersed in the functional film after heat treatment. Before heat treatment, the functional film is composed of TiO 2 Thin films (3nm to 5nm thickness) and VO 2 The thin film (thickness 200nm to 300nm) exists in the form of a thin film. After heat treatment, as shown in the figure, Ti is uniformly distributed in the depth range of 0 to 90nm, which means that Ti is finally evenly dispersed in the functional film. This also means that Ti diffuses through the entire functional film in the thickness direction and reaches the surface, and represents the uniformity of doping according to an embodiment.

[0107] That is, as shown in the figure, the EDX curve of Ti remains substantially constant in the depth range of 0 to 90 nm, and this value is more significantly different from the value in the EDX curve of Al in the figure.

[0108] Next, a more detailed look at doping uniformity within the functional thin film is taken.

[0109] Continue to refer to Figure 8 , it can be seen that V and Ti have similar distribution levels (standard deviation). This more clearly shows the uniformity of doping. This shows that Ti in VO 2 The film is uniformly distributed like V. This indicates that the boundary between the sacrificial layer and the main oxide layer disappears after the post-heat treatment process according to an embodiment. Figures 9 and 10 Provide explanation.

[0110] Fig. 9 Only the enlarged Figure 8 The mapping results of Ti in the EDX curve of . The average value (about 2647) and standard deviation (about 567) are calculated in the range of 0 to 90 nm. Fig.10 Only the enlarged Figure 8 The mapping result of V in the EDX curve of . The average value (about 36487) and the standard deviation (about 778) are calculated in the range of 0 to 90 nm. At this time, it can be noted that by arbitrarily setting the y-axis (arb.), the intensity itself has no meaning, but the standard deviation of Ti and the standard deviation of V can be compared. That is, it can be noted that comparative data is provided on whether Ti is distributed as uniformly as V in the functional film.

[0111] As shown in the figure, Ti corresponding to the heterogeneous metal element and VO constituting the main oxide layer 2 V in the functional thin film may have distribution levels similar to each other. That is, within the functional thin film, Ti may be distributed as uniformly as V. For example, the distribution level of Ti corresponding to the heterogeneous metal element may be similar to that of VO constituting the main oxide layer. 2 The distribution level of V has a difference within 30%. In more detail, since the difference of two standard deviations (211) divided by the value of EDX (778) of V is 0.271, it can have a difference within 27.1%. At this time, for the convenience of calculation, the decimal point is appropriately processed by rounding, discarding, etc., but for more accurate calculation, even the decimal point can be considered.

[0112] In the above, the results of TEM-EDX are described from the perspective of the distribution level of intensity. However, when the intensity is converted into the average concentration, the analysis may be performed from the perspective of the distribution level of the average concentration instead of the intensity.

[0113] (Example of experimental data analysis on high crystallinity in functional thin films)

[0114] Fig.11 XRD (X-ray diffraction) data of the main body according to one embodiment is shown. XRD shows the crystallinity of the entire film. As shown in the figure, the growth of TiO 2 VO on 2 After heat treatment, only one main VO 2 peak (see the part indicated by the arrow in the figure).

[0115] That is, the main VO 2 The XRD peak of VO does not appear in the range of 2θ = 20 to 60°, but only in the range of 2θ = 60 to 70°. This indicates that 2 It is a thin film with high crystallinity (Epitaxial thin film: epitaxial thin film). On the other hand, when VO 2 When grown alone, multiple main peaks appear, so it can be seen that it is a polycrystalline thin film.

[0116] In more detail, in the X-ray diffraction pattern measured by XRD, the TiO 2 VO on 2 There is a peak A appearing in the range of 2θ=64.92±0.5°, and in the absence of TiO 2 Under the condition of , VO2 grown alone has a total of eight peaks appearing in the range of 2θ = 27.84 ± 0.5°, 2θ = 33.4 ± 0.5°, 2θ = 37.08 ± 0.5°, 2θ = 42.26 ± 0.5°, 2θ = 49.52 ± 0.5°, 2θ = 55.54 ± 0.5°, 2θ = 57.64 ± 0.5°, and 2θ = 64.94 ± 0.5° (in order, each peak is called a1, b1, c1, d1, e1, f1, g1, h1). A single peak A represents an epitaxial thin film, and multiple peaks a1, b1, c1, d1, e1, f1, g1, h1 represent a polycrystalline thin film.

[0117] At this time, the half width FWHM of the peak A may be 1.0° or less. Preferably, it may be 0.79° or less. This may support high crystallinity in the functional film according to an embodiment.

[0118] On the other hand, from the perspective that tiny peaks may also appear in the XRD data, the term "main VO 2 "Peak" can only consider peaks with a certain intensity or above. As an example, peaks with an intensity not exceeding 10% of the maximum peak intensity in the figure are not considered as objects. That is, when the intensity of peak A is 632.68, peaks with an intensity below 63.27 can be ignored.

[0119] Although the above description focuses on the embodiment in which eight peaks appear, it is not necessarily limited to this. As long as the number of peaks indicates that it is polycrystalline, embodiments with less than or more than eight peaks are possible. It should be noted that compared with the case in which there is only one main peak in the case of epitaxial thin film, multiple main peaks can appear in the case of polycrystalline thin film.

[0120] The functional film according to one embodiment shows that the crystal structure of the sacrificial layer of the main oxide layer is affected by the post-heat treatment process and crystallized with high orientation, and the metal ions of the sacrificial layer are doped into the entire main oxide layer by self-diffusion, and the crystal structure of the main oxide layer remains the same as before after doping. That is, the crystal structure of the main oxide can be maintained despite the doping of heterogeneous metal elements.

[0121] As described above, it can be seen that according to the functional film of one embodiment, the boundary between the sacrificial layer and the main oxide layer disappears after the post-heat treatment process, the crystal structure of the main oxide layer remains unchanged before and after doping, and the functional film as a whole can form a highly crystalline film in the form of sacrificial layer metal ion doping.

[0122] An embodiment of the present invention has been described above. However, without departing from the scope of the concept of the present invention as described in the patent claims, the present invention can be modified and altered in various ways by adding, changing or deleting components, which also falls within the scope of the rights of the present invention.

[0123] (Explanation of Reference Numerals)

[0124] CP: Conductive particles

[0125] R: Base resin

[0126] 100: Main body

[0127] 110: Base substrate

[0128] 120: Functional film

[0129] 200, 300: External electrodes

[0130] 210, 310: Conductive resin layer

[0131] 220, 320: Metal layer

[0132] 1000: Energy sensing electronic components

Claims

1. An oxide film ， in, include: Single crystal substrates; and a main oxide layer, the main oxide layer being stacked on the single crystal substrate and doped with a heterogeneous metal element, In energy dispersive X-ray analysis (EDX) using a transmission electron microscope (TEM), the foreign metal element and the metal element of the metal oxide constituting the main oxide layer are uniformly distributed.

2. The oxide thin film according to claim 1, in, The EDX curve distribution level of the heterogeneous metal element has a difference within 30% compared with the EDX curve distribution level of the metal element of the metal oxide constituting the main oxide layer.

3. The oxide thin film according to claim 1, in, A standard deviation of an EDX curve of the dissimilar metal element measured in the thickness direction of the main oxide layer is within 30% of a standard deviation of an EDX curve of a metal element of a metal oxide constituting the main oxide layer.

4. The oxide thin film according to claim 1, in, The main oxide layer is formed by integrating the crystalline sacrificial layer of the heterogeneous metal element and the pre-oxide thin film formed on the crystalline sacrificial layer through a post-heat treatment process.

5. The oxide thin film according to claim 4, in, The crystalline sacrificial layer grows on the single crystal substrate along a crystal direction of the single crystal substrate.

6. The oxide thin film according to claim 5, in, The pre-oxide thin film is a film amorphized on the crystalline sacrificial layer.

7. The oxide thin film according to claim 6, in, The main oxide layer is formed by crystallizing the amorphized pre-oxide film in a predetermined direction along the crystallization direction of the crystallization sacrificial layer through the post-heat treatment process.

8. The oxide thin film according to claim 1, in, The single crystal substrate is sapphire (Al 2 O 3 ) single crystal substrate, The main oxide layer is VO 2 At least a portion of the V ions in the crystal lattice are replaced (doped) with Ti ions.

9. An oxide film ， in, include: Single crystal substrates; and VO 2 layer, the VO 2 The layers are stacked on the single crystal substrate and doped with Ti, The VO 2 Layer VO 2 The XRD peak does not appear in the range of 2θ=20 to 60°, but only appears in the range of 2θ=60 to 70°.

10. The oxide thin film according to claim 9, in, The VO 2 The layer is defined as a main VO layer with a certain strength above 2θ=20-70°. 2 Multiple XRD peaks appear for high crystallinity epitaxial films rather than polycrystalline films.

11. The oxide thin film according to claim 10, in, The main VO of the polycrystalline thin film 2 XRD peaks appear in two or more of the range of 2θ=27.84±0.5°, 2θ=33.4±0.5°, 2θ=37.08±0.5°, 2θ=42.26±0.5°, 2θ=49.52±0.5°, 2θ=55.54±0.5°, 2θ=57.64±0.5° and 2θ=64.94±0.5°, and the main VO of the epitaxial film 2 The XRD peak only appears in the range of θ=64.92±0.5°.

12. The oxide thin film according to claim 9, in, The VO 2 The main VO layer 2 The half width HWHM of the XRD peak is 1° or less.

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