Electromagnetic interference shielding film with metal-MXene heterogeneous layer and its manufacturing method

Abstract

The present invention relates to an electromagnetic interference shielding film having heterogeneously stacked metal-MXene layers and a method for manufacturing the same. Through a sandwich structure in which MXene layers are formed between metal thin film layers, it has superior electromagnetic shielding efficiency compared to conventional films even at a thin thickness.

Description

Technology Field

[0001] The present invention relates to an electromagnetic interference shielding film in which metal-MXene (MX) is heterogeneously laminated and a method for manufacturing the same. More specifically, the invention relates to an embedded MXene-in-metal (EXIM) electromagnetic interference shielding film in which MXene is laminated in a sandwich structure between metals, which can have excellent shielding performance at a thin thickness. Background Technology

[0002] With the advancement of smart electronic devices, portability and wearability have become increasingly important, leading to a significant reduction in the physical thickness of IC chips through the development of wafer thinning and wafer-free integrated circuit (IC) chips. Consequently, methods to reduce the thickness of packaging materials are being researched to decrease the total thickness of electronic devices; among these efforts, various experiments are being conducted to reduce the thickness of electromagnetic interference (EMI) shielding films, which protect IC chips from electromagnetic contamination.

[0003] However, conventional electromagnetic interference (EMC) shielding films are in the form of thick metal cages surrounding IC chips, and there is a problem in that shielding performance deteriorates as the thickness of the metal cage is reduced. Therefore, to overcome the performance limitations of EMC shielding films, pores were formed in metal and two-dimensional conductive shielding materials, such as titanium carbide / nitride, to induce absorption of electromagnetic waves through absorption during multiple internal reflections (AMIR) to improve shielding efficiency. However, there are limitations in reducing the thickness of shielding films containing such materials, and they suffer from problems of low spatial uniformity and high bending stiffness. Furthermore, since shielding films containing pores require high processing temperatures and are incompatible with conventional packaging technology that involves direct deposition on the IC chip surface, there are currently no successful cases of shielding films containing pores being formed on IC chips.

[0004] Therefore, there is a need to develop an electromagnetic interference shielding film that possesses excellent AMIR performance, has a thin thickness, and is practically depositable. The problem to be solved

[0005] The first technical problem that the present invention aims to solve is to provide an electromagnetic interference shielding film in which metal-MXene is heterolayered.

[0006] The second technical objective of the present invention is to provide a method for manufacturing an electromagnetic interference shielding film in which metal-MXene is heterolayered to achieve the first technical objective. means of solving the problem

[0007] To achieve the first technical objective described above, the present invention provides an electromagnetic interference shielding film in which a metal-MXene is heterolayered. The electromagnetic interference shielding film in which the metal-MXene is heterolayered has a sandwich structure comprising a lower metal thin film, MXene located on the metal, and an upper metal thin film for electromagnetic shielding located on the MXene and made of the same material as the lower metal thin film. The lower metal thin film and the upper metal thin film improve electromagnetic shielding performance by inducing AMIR through dipoles on the surface of the MXene at the interface in contact with the MXene.

[0008] To achieve the second technical objective described above, the present invention manufactures an electromagnetic interference shielding film in which metal and MXene are heterolayered by forming a sacrificial layer on a substrate, depositing a lower metal thin film on the sacrificial layer, coating an interface adhesion promoter on the lower metal thin film and then coating a MXene layer, and then coating an interface adhesion promoter on the MXene layer and then depositing an upper metal thin film. An electromagnetic interference shielding film with a multilayer structure can be manufactured by additionally stacking a MXene layer and a metal thin film in sequence on the upper metal thin film. Effects of the invention

[0009] According to the present invention described above, the electromagnetic interference shielding film with heterolayer stacking of metal-MXene has no constraints on the minimum thickness required for pore formation by inserting a MXene layer with a non-porous structure into a metal thin film layer, thereby enabling the manufacture of an electromagnetic interference shielding film with a thin thickness compared to conventional electromagnetic interference shielding films containing pores, and possesses excellent uniformity and processing compatibility. Therefore, the electromagnetic interference shielding film with heterolayer stacking of metal-MXene has low bending stiffness due to its thin thickness, allowing it to be easily formed on the surface of IC chips of various shapes. Furthermore, since it does not include the step of additionally forming a pore structure within the electromagnetic interference shielding film with heterolayer stacking of metal-MXene, it exhibits excellent spatial uniformity and reproducibility, so the passivation yield does not decrease, resulting in excellent shielding performance.

[0010] A heterogeneous stacked metal-MXene electromagnetic interference shielding film can achieve excellent electromagnetic shielding efficiency because an electromagnetic wave confinement wall is formed at the interface where the metal thin film layer and the MXene layer are bonded due to high reflection loss caused by the conductivity mismatch between the metal thin film layer and the MXene layer, and the interface and the MXene flake dipoles absorb reflected waves to generate effective AMIR (Absorption during multiple internal reflections) within the electromagnetic interference shielding film.

[0011] The electromagnetic interference shielding film with heterogeneous stacking of metal-MXene may have a multilayer stacked structure in which a metal thin film layer and a MXene layer are stacked in sequence, and may have excellent shielding performance as the number of junctions between the metal thin film layer and the MXene layer increases. Brief explanation of the drawing

[0012] FIG. 1 is a schematic diagram of a heterogeneously laminated metal-MXene electromagnetic interference shielding film according to a preferred embodiment of the present invention. FIG. 2 is a graph showing the shielding effectiveness (SE) according to a preferred embodiment of the present invention. Figure 3 is a graph benchmarking the average SE according to the thickness of the electromagnetic interference shielding film according to a preferred embodiment of the present invention. Figure 4 shows Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Energy dispersive X-ray spectroscopy (EDS) mapping images of an electromagnetic line shielding film according to a preferred embodiment of the present invention. FIG. 5 is a bending-related image and curvature measurement graph according to a preferred embodiment of the present invention. FIG. 6 is a graph showing the average SE according to the thickness of the electromagnetic interference shielding film according to a preferred embodiment of the present invention, and a graph showing the slope values ​​of the graphs and the relationship between electrical conductivity. FIG. 7 is a graph showing the stacking effect on the average SE value and the measured SE value according to a preferred embodiment of the present invention. FIGS. 8 and FIGS. 9 are graphs showing the results of repeated SE measurements according to a preferred embodiment of the present invention. FIG. 10 is a graph showing an AMIR mechanism according to a preferred embodiment of the present invention. FIG. 11 is a graph showing the SE curve of an electromagnetic interference shielding film according to a preferred embodiment of the present invention. FIG. 12 is a graph showing the synergy SE and average SE according to the thickness of the electromagnetic interference shielding film according to a preferred embodiment of the present invention. FIG. 13 is a graph of the synergy SE measurement results according to the presence or absence of a metal thin film and a MXene well structure according to a preferred embodiment of the present invention. FIG. 14 is a graph showing the SE measurement results according to the multilayer structure of the electromagnetic interference shielding film according to a preferred embodiment of the present invention. FIG. 15 is a graph showing the average SE and electrical resistance values ​​measured with and without a passivation layer on an electromagnetic interference shielding film according to a preferred embodiment of the present invention. FIG. 16 are images showing changes in the surface shape of an electromagnetic interference shielding film with or without a passivation layer according to a preferred embodiment of the present invention. FIG. 17 is a graph showing the average SE curve of an electromagnetic interference shielding film with or without a passivation layer according to a preferred embodiment of the present invention. FIG. 18 is a graph showing the malfunction caused by electromagnetic noise of a Bluetooth speaker according to a preferred embodiment of the present invention. FIG. 19 is a graph showing the effect of shielding on the integrity of a Bluetooth signal according to a preferred embodiment of the present invention. Specific details for implementing the invention

[0013] The present invention is capable of various modifications and may take various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the invention to the specific disclosed forms, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0014] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0015] The term "MXene" used in the present invention refers to a new type of two-dimensional material, which is a material mainly belonging to the metal carbide, nitride, or carbide-nitride series, and can be used in combination with MXene, having the same meaning in this specification.

[0016] The term "electromagnetic interference shielding film with heterogeneous stacking of metal-MXene" used in the present invention refers to an electromagnetic interference shielding film in which MXene is stacked in a sandwich structure between metal thin films. To distinguish it from electromagnetic interference shielding films using a different structure or other materials than the present invention, it may be used interchangeably as "Embedded MXene-in-metal (EXIM) electromagnetic interference shielding film," and has the same meaning in this specification.

[0017] Hereinafter, various embodiments of the present invention will be described in more detail with reference to the attached drawings.

[0019] Examples

[0020] The present invention provides an electromagnetic interference shielding film in which metal-MXene is heterolayered.

[0021] FIG. 1 is a schematic diagram of a heterogeneously laminated metal-MXene electromagnetic interference shielding film of the present invention.

[0022] Referring to FIG. 1, the electromagnetic interference shielding film having a heterogeneous stack of metal-MXene has a sandwich structure comprising a lower metal thin film (101) in FIG. 1 (a), a MXene layer (201) deposited on the lower metal thin film (101), and an upper metal thin film (102) deposited on the MXene layer (201). Referring to FIG. 1 (b), the electromagnetic interference shielding film having a heterogeneous stack of metal-MXene can form a multilayer sandwich structure including two or more MXene layers through repeated stacking of metal thin films (101, 102, 103, 104, 105) and MXene layers (201, 202, 203, 204).

[0023] When a multilayer sandwich structure is formed containing two or more layers of metal thin films and MXene, as the junction between the metal thin film layer and the MXene layer increases, the electric dipoles of the terminal groups on the surface of the MXene layer interact with electromagnetic waves through dipole polarization and can attenuate electromagnetic waves through a relaxation mechanism. Therefore, if the junction between the metal thin film layer and the MXene layer increases due to multilayer stacking, the electromagnetic shielding efficiency can be improved.

[0024] It is desirable to form the above MXene thin film layer thinly to the minimum thickness required to ensure a uniform film quality. Since the dipoles present at the metal-MXene interface play a key role in the AMIR effect caused by the sandwich structure, if the MXene thin film layer can be formed uniformly, a high-performance shielding effect is maintained even if the thickness of the film is reduced from 1 μm to 0.2 μm. As the thickness decreases, the bending strength is reduced, allowing for effective adhesion to the surface of the IC chip.

[0025] It is preferable that the electromagnetic interference shielding film having heterolayered metal-MXene has a thickness of 2 μm or less. If the thickness of the electromagnetic interference shielding film having heterolayered metal-MXene exceeds 2 μm, there may be a limit to the bending when the electromagnetic interference shielding film of the present invention is attached to an IC chip for electromagnetic shielding, making it difficult to attach easily.

[0026] The above-mentioned metal-MXene heterolayered electromagnetic interference shielding film may have an electromagnetic shielding efficiency (SE) of 69.2 (±1.6) dB or higher.

[0027] The electromagnetic interference shielding film of the present invention, which is heterolayered with metal-MXene, may have a passivation layer formed on top to prevent oxidation. When a passivation layer is formed on the electromagnetic interference shielding film of the heterolayered metal-MXene, damage to the electromagnetic interference shielding film caused by oxidation, such as humidity or discoloration, can be prevented, thereby preventing a decrease in shielding performance.

[0028] The above metal thin film may be any one selected from the group consisting of metal materials including Cu, Au, and Ag, but is not limited thereto, and any metal capable of blocking, absorbing, or reflecting electromagnetic waves is sufficient.

[0030] The present invention provides a method for manufacturing an electromagnetic interference shielding film in which metal-MXene is heterolayered.

[0031] An electromagnetic interference shielding film having a heterogeneous stack of metal-MXene is manufactured by comprising: a first step of forming a sacrificial layer on a substrate; a second step of depositing a lower metal thin film on the sacrificial layer formed through the first step; a third step of coating an interface adhesion promoter on the lower metal thin film deposited through the second step; a fourth step of coating a MXene layer on the lower metal thin film coated with an interface adhesion promoter through the third step; a fifth step of coating an interface adhesion promoter on the MXene layer coated through the fourth step; and a sixth step of depositing an upper metal thin film on the MXene layer coated with an interface adhesion promoter through the fifth step.

[0032] In the first step above, a sacrificial layer is formed on the substrate.

[0033] In the second step above, a lower metal thin film is formed on the sacrificial layer.

[0034] The above-mentioned lower metal thin film may be any one selected from the group consisting of metal materials including Cu, Au, and Ag, but is not limited thereto, and any metal capable of blocking, absorbing, or reflecting electromagnetic waves is sufficient.

[0035] In the third step above, an interface adhesion promoter is coated on the lower metal thin film to bond the MXene layer.

[0036] The above interface adhesion promoter may be APTES or TiOx, but is not limited thereto, and any material capable of easily bonding the interface between the metal thin film and the MXene layer is sufficient.

[0037] In the above fifth step, a MXene thin film layer is deposited.

[0038] It is desirable to form the above MXene thin film layer thinly to the minimum thickness required to ensure a uniform film quality. Since the dipoles present at the metal-MXene interface play a key role in the AMIR effect caused by the sandwich structure, if the MXene thin film layer can be formed uniformly, a high-performance shielding effect is maintained even if the thickness of the film is reduced from 1 μm to 0.2 μm. As the thickness decreases, the bending strength is reduced, allowing for effective adhesion to the surface of the IC chip.

[0039] In the fifth step above, an interfacial adhesion promoter is coated on the MXene layer.

[0040] The above interface adhesion promoter may be APTES or TiOx, but is not limited thereto, and any material capable of easily bonding the interface between the metal thin film and the MXene layer is sufficient.

[0041] In the above sixth step, an upper metal thin film is deposited to manufacture an electromagnetic interference shielding film in which metal-MXene is heterolayered.

[0042] The upper metal thin film may be any one selected from the group consisting of metal materials including Cu, Au, and Ag, but is not limited thereto, and any metal capable of blocking, absorbing, or reflecting electromagnetic waves is sufficient.

[0043] The above-mentioned metal-MXene heterolayered electromagnetic interference shielding film can form a multilayer electromagnetic interference shielding film with two or more MXene layers through the repetition of the above-mentioned third to sixth steps.

[0044] It is preferable that the electromagnetic interference shielding film having heterolayered metal-MXene has a thickness of 2 μm or less. If the thickness of the electromagnetic interference shielding film having heterolayered metal-MXene exceeds 2 μm, there may be a limit to the bending when the electromagnetic interference shielding film of the present invention is attached to an IC chip for electromagnetic shielding, making it difficult to attach easily.

[0045] The above-mentioned metal-MXene heterolayered electromagnetic interference shielding film may have an electromagnetic shielding efficiency (SE) of 69.2 (±1.6) dB or higher.

[0046] The electromagnetic interference shielding film of the present invention, which is heterolayered with metal-MXene, may have a passivation layer formed on top to prevent oxidation. When a passivation layer is formed on the electromagnetic interference shielding film of the heterolayered metal-MXene, damage to the electromagnetic interference shielding film caused by oxidation, such as humidity or discoloration, can be prevented, thereby preventing a decrease in shielding performance.

[0048] Preparation Example 1-1: MXene(MX) / Cu structure

[0049] Ti3C2T by selectively etching Al from Ti3AlC2 x MXene was synthesized. Ti3C2T x A MXene mixture with a concentration of 2 mg / mL was prepared by dispersing MXene flakes in distilled water, and then ultrasonically treated to prepare a MXene colloidal solution. A PMMA thin film was formed as a sacrificial layer on a silicon substrate, and then the MXene colloidal solution was spray-coated onto the PMMA thin film and heated at 40°C to form a MXene layer. APTES was applied onto the MXene layer, and then a metal thin film was formed by thinly depositing Cu using an electron beam deposition system under high vacuum conditions. After removing the sacrificial layer, an electromagnetic interference shielding film with an MX / Cu structure was prepared.

[0051] Preparation Example 1-2: Cu / MX structure

[0052] It was prepared under the same conditions as Preparation Example 1-1 above, except that the deposition order of Cu and MX was changed.

[0054] Preparation Examples 1-3: Cu / MX(0.4 um) / Cu structure

[0055] It was manufactured under the same conditions as Manufacturing Example 1-2, except that a MXene layer was coated to a thickness of 0.4 μm, APTES was applied on the MXene layer, and then Cu was thinly deposited using an electron beam deposition machine under high vacuum conditions to form an upper metal thin film.

[0057] Preparation Examples 1-4: Cu / MX(0.2 µm) / Cu structure

[0058] It was prepared under the same conditions as Preparation Examples 1-3 above, except that the MXene layer was coated to a thickness of 0.2 μm.

[0059] Preparation Examples 1-5: Cu / MX(1 µm) / Cu Structure

[0060] It was manufactured under the same conditions as Manufacturing Examples 1-3 above, except that the MXene layer was coated to a thickness of 1 μm.

[0062] Preparation Examples 1-6: Structure containing 2 layers of MX

[0063] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that a multilayer was formed by repeating the deposition of a MXene layer and a metal thin film on the upper metal thin film in the same manner once.

[0065] Preparation Examples 1-7: Structure containing 3 layers of MX

[0066] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that a multilayer was formed by repeating the deposition of a MXene layer and a metal thin film on the upper metal thin film in the same manner twice.

[0068] Preparation Examples 1-8: Structure containing 4 layers of MX

[0069] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that a multilayer was formed by repeating the deposition of a MXene layer and a metal thin film on the upper metal thin film in the same manner three times.

[0071] Preparation Example 1-9: Structure containing 6 layers of MX

[0072] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that a multilayer was formed by repeating the MXene layer and the metal thin film five times in the same manner on the upper metal thin film.

[0074] Preparation Example 1-10: Structure including a passivation layer

[0075] It was manufactured under the same conditions as Manufacturing Examples 1-7 above, except that a Cr-Al thin film was formed as a passivation layer on the uppermost metal thin film.

[0077] Preparation Example 2: Ag / MX / Ag structure

[0078] It was prepared under the same conditions as Preparation Examples 1-4 above, except that Ag was used instead of Cu for the upper metal thin film.

[0080] Preparation Example 3: TiOx / MX / TiOx structure

[0081] It was prepared under the same conditions as Preparation Examples 1-4 above, except that the upper metal thin film was made of TiOx instead of Cu.

[0083] Preparation Example 4: Au / Mx / Au structure

[0084] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that the upper metal thin film was made of Au instead of Cu.

[0086] Comparative Example 1-1

[0087] A single metal electromagnetic interference shielding film with a copper thickness of 0.1 μm was manufactured.

[0089] Comparative Example 1-2

[0090] A single metal electromagnetic interference shielding film with a copper thickness of 0.2 μm was manufactured.

[0092] Comparative Examples 1-3

[0093] A single metal electromagnetic interference shielding film with a copper thickness of 0.4 μm was manufactured.

[0094] Comparative Examples 1-4

[0095] A single metal electromagnetic interference shielding film with a copper thickness of 0.6 μm was manufactured.

[0097] Comparative Example 2-1

[0098] After metallizing a silicon substrate with an Al thin film with a thickness of 100 nm, a MXene colloidal solution prepared through Preparation Example 1-1 was spray-coated onto the Al thin film to form a MXene layer with a thickness of 0.2 μm, and a single MXene electromagnetic interference shielding film separated from the substrate was prepared by selective electrochemical etching of the Al layer.

[0100] Comparative Example 2-2

[0101] It was manufactured under the same conditions as Comparative Example 2-1, except that the MXene layer was coated to a thickness of 0.4 μm.

[0103] Comparative Example 2-3

[0104] It was manufactured under the same conditions as Comparative Example 2-1, except that the MXene layer was coated to a thickness of 0.6 μm.

[0106] Comparative Example 2-4

[0107] It was manufactured under the same conditions as Comparative Example 2-1 above, except that the MXene layer was coated to a thickness of 1 μm.

[0109] Comparative Example 3-1

[0110] A single metal electromagnetic interference shielding film with a thickness of 0.1 μm of TiOx was prepared.

[0112] Comparative Example 3-2

[0113] A single metal electromagnetic interference shielding film with a thickness of 0.2 μm of TiOx was prepared.

[0115] Comparative Example 3-3

[0116] A single metal electromagnetic interference shielding film with a thickness of 0.3 μm of TiOx was prepared.

[0118] Comparative Example 4-1

[0119] A single metal electromagnetic interference shielding film with an Au thickness of 0.1 μm was manufactured.

[0121] Comparative Example 4-2

[0122] A single metal electromagnetic interference shielding film with an Au thickness of 0.2 μm was manufactured.

[0124] Comparative Example 4-3

[0125] A single metal electromagnetic interference shielding film with an Au thickness of 0.3 μm was manufactured.

[0127] Comparative Example 5-1

[0128] A single metal electromagnetic interference shielding film with an Ag thickness of 0.1 μm was manufactured.

[0130] Comparative Example 5-2

[0131] A single metal electromagnetic interference shielding film with an Ag thickness of 0.2 μm was manufactured.

[0133] Comparative Example 5-3

[0134] A single metal electromagnetic interference shielding film with an Ag thickness of 0.3 μm was manufactured.

[0136] Comparative Example 6

[0137] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that an Al2O3 layer was formed instead of a MXene layer.

[0139] Comparative Example 7

[0140] It was prepared under the same conditions as Preparation Examples 1-4 above, except that a TiOx layer was formed instead of a MXene layer.

[0142] Comparative Example 8

[0143] It was manufactured under the same conditions as Manufacturing Examples 1-4 above, except that an Au layer was formed instead of a MXene layer.

[0145] Measurement Example 1

[0146] Figure 2 is a graph showing the measured SE (shielding effectiveness) of Preparation Example 1-9, which is an electromagnetic interference shielding film in which a metal-MXene heterolayer has 12 planes at the junction of the metal thin film and the MXene layer.

[0147] Referring to FIG. 2, Preparation Example 1-9, having a thickness of 1.9 μm, is SE total SE of 69.2 (±1.6) dB or higher in the X-band condition of 8.2 GHz to 12.4 GHz total It was confirmed that it is.

[0148] Figure 3 is a graph showing the average SE value for comparing the performance of the metal-MXene heterolayered electromagnetic interference shielding film of the present invention.

[0149] Referring to FIG. 3, it was confirmed that Preparation Examples 1-3 to 1-9 of the present invention, having a sandwich structure in which a metal thin film and a MXene layer are multilayer stacked, have a thinner thickness and an excellent average SE value compared to Comparative Examples 1-1 to 5 of the present invention or electromagnetic interference shielding films made of a single metal or other composite materials according to data disclosed in prior papers. In FIG. 3, electromagnetic interference shielding films having a shielding thickness of less than 2 μm had an average SE value of less than 60 dB, but it was confirmed that the preparation examples of the present invention have an excellent average SE value of 60 dB to 80 dB even when manufacturing electromagnetic interference shielding films of 2 μm or less.

[0150] Therefore, through FIGS. 2 and 3, it can be seen that the electromagnetic interference shielding film with heterogeneous stacking of metal-MXene has excellent shielding performance even with a thickness of 2 μm or less, and when the thickness of the shielding film is 0.1 μm to 2 μm, the SEtotal value is 69.2 (±1.6) dB or higher, indicating that excellent shielding performance is maintained even with a thin thickness.

[0152] Figure 4 shows Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Energy dispersive X-ray spectroscopy (EDS) mapping images of the electromagnetic interference shielding film of Preparation Examples 1-10. (b) is an image mapping Cu, (c) is an image mapping Ti, (d) is an image mapping Cr, and (e) is an image mapping Al, and (f) is an TEM image of the interface between the lower copper thin film and the MXene layer, and (g) is an TEM image of the interface between the upper copper thin film and the MXene layer.

[0153] Referring to Fig. 4, it can be confirmed that Preparation Examples 1-10 have a sandwich structure in which four 0.1 μm thick Cu thin films and three 0.2 μm thick MXene layers are alternately stacked, and it can be seen through elemental mapping images that they are uniformly stacked. Since the Cu thin films and the MXene layers do not mix and form a uniform layer, the electromagnetic shielding performance can be improved due to interfacial reactions at the junction. In addition, referring to the TEM images, no pores are formed inside the electromagnetic interference shielding film, and the interface between the copper thin film and the MXene layer junction is almost free of pores due to the interfacial adhesion promoter. Therefore, non-uniformity of AMIR caused by the size or location of pores can be prevented.

[0155] Figure 5 is a bending test image and curvature measurement graph of the electromagnetic interference shielding film of Manufacturing Examples 1-10.

[0156] Referring to FIG. 5, through (a), it can be visually confirmed that the heterolayered metal-MXene electromagnetic interference shielding film bends with a curvature of 0.5 mm. Additionally, it was confirmed that reversible recovery is possible through the curvature of (b). Since the above Manufacturing Examples 1-10 have low bending stiffness, a support substrate is required, and it can be seen that conformal passivation of the IC chip is possible through this.

[0158] Measurement Example 2

[0159] Figure 6 shows graphs related to the average SE and electrical conductivity calculated based thereon, depending on the thickness of the electromagnetic interference shielding films of Comparative Examples 1-1 to 5-3. (a) Comparative Examples 1-1 to 1-4, which are Cu; (b) Comparative Examples 2-1 to 2-4, which are MX; (c) Comparative Examples 4-1 to 4-3, which are Au; (d) Comparative Examples 5-1 to 5-3, which are Ag; and (e) Comparative Examples 3-1 to 3-3, which are TiOx, were measured as single thin films.

[0160] Referring to FIG. 6, (a) to (e) show that the average SE increased linearly with the thickness of the shielding film, and FIG. 6 (f) shows that the copper single film has superior shielding efficiency compared to the MXene single film. However, the comparative examples in FIG. 6 did not exceed an average SE of 50 dB.

[0161] On the other hand, FIG. 7 is a graph showing the measured SE values ​​of the electromagnetic interference shielding films of Preparation Examples 1-1 to 1-3, where (a), (d), and (g) relate to Preparation Example 1-1, (b), (e), and (h) relate to Preparation Example 1-2, and (c), (f), and (i) relate to Preparation Example 1-3.

[0162] Referring to Fig. 7, it has an excellent average SE value of 50 dB or more compared to the comparative examples of the single metal thin film of Fig. 6, and also has an excellent average SE value compared to the comparative examples in Fig. 7 (f).

[0163] Therefore, as shown in Figures 6 and 7, when the copper film and MXene film form a sandwich structure compared to a single copper film and a single MXene film, copper and MXene are selectively enhanced SE A As SE increases total It can be seen that this has improved.

[0165] FIG. 8 shows the SE of the electromagnetic interference shielding films of (a) Preparation Examples 1-3 and (b) Comparative Example 6. total These are graphs measured repeatedly.

[0166] FIG. 9 shows the SE of the electromagnetic interference shielding films of (a) Preparation Examples 1-4, (b) Comparative Examples 1-4, and (c) Comparative Examples 2-3. total These are graphs measured repeatedly.

[0167] Referring to FIGS. 8 and 9, Preparation Example 1-3, in which a MXene layer with a thickness of 0.2 μm is formed between copper thin films of an electromagnetic interference shielding film with a thickness of 0.4 μm as shown in FIG. 8, exhibits superior SE compared to Comparative Example 6, in which an Al2O3 layer of the same thickness is formed. total The electromagnetic interference shielding films of Preparation Examples 1-4, Comparative Examples 1-4, and Comparative Examples 2-3, which have a thickness of 0.6 μm in Fig. 9, had significantly lower SE compared to Preparation Example 1-4, where Comparative Examples 1-4 and 2-3 are single metal thin films. total It was confirmed that it has a value.

[0168] Therefore, through FIGS. 8 and 9, it can be seen that Preparation Example 1-4, having a sandwich structure, exhibits superior shielding performance compared to a single metal thin film, and that even with the same sandwich structure, the combination of the metal thin film and the MXene layer demonstrates superior shielding efficiency. Furthermore, when comparing the graphs of Preparation Example 1-3 and Preparation Example 1-4, the thickness of the MXene layer did not result in a significant difference in the effect of electromagnetic shielding.

[0170] FIG. 10 is a graph showing the AMIR mechanism of (a) Preparation Example 1-3, (b) Preparation Example 1-4, (c) Preparation Example 3-2, (d) Comparative Example 7, and (e) Comparative Example 8, and FIG. 11 is the SE of (a) Preparation Example 1-5, (b) Preparation Example 1-4, (c) Preparation Example 4-2, (d) Preparation Example 2-2, (e) Preparation Example 3-2, (f) Comparative Example 7, and (g) Comparative Example 8. totalThese are graphs comparing graphs showing values, and FIG. 12 is a graph showing the synergy SE and average SE of Manufacturing Examples 1-3 to 1-5, and FIG. 13 is a graph showing the synergy SE values ​​of Manufacturing Examples and Comparative Examples 7 to 8.

[0171] Referring to FIG. 10, (a) through (d) form well shapes. FIG. 10 (a) and (b) show that the copper thin film acts as a wall to confine electromagnetic waves, allowing for effective AMIR to be performed within the electrically conductive and dipole-rich MXene layer when the waves are absorbed. However, when comparing (a) and (b), the difference in thickness of the MXene layer did not significantly affect AMIR. Nevertheless, since a superior AMIR mechanism can be performed compared to (c) and (d), it can be confirmed that AMIR is effectively generated through the heterojunction of the metal thin film and the MXene layer. To verify this mechanism more specifically, referring to FIG. 11, for (c) and (d), where the metal thin film is Au or Ag, SEtotal values ​​similar to those of (b), an electromagnetic cross-line shielding film of the same thickness using a copper thin film, were observed because Au and Ag have excellent conductivity. However, in (e), AMIR was not smoothly driven due to the resistance of TiOx. In addition, in (f), TiOx, which has similar electrical conductivity to MXene, was deposited instead of a MXene layer between copper thin films, but no AIMR mechanism occurred, and in (g), since the conductivity of Cu and Au is similar, no AIMR mechanism occurred, so no synergistic SE was measured in Fig. 13.

[0172] Therefore, through FIGS. 10 to 13, it can be seen that the conductivity mismatch at the junction of the metal thin film and the MXene layer can efficiently trap electromagnetic waves in the MXene layer, and that the electromagnetic interference shielding film formed of the copper thin film and the MXene layer has the best shielding efficiency.

[0174] FIG. 14 is a graph showing the SE measurement results according to the multilayer structure of Preparation Examples 1-4, 1-6 to 1-9. (a) is Preparation Example 1-4, (b) is Preparation Example 1-6, (c) is Preparation Example 1-7, (d) is Preparation Example 1-8, and (e) is Preparation Example 1-9.

[0175] Referring to Fig. 14, it can be seen that the SE value improves as the junction between the copper thin film and the MXene layer increases. Therefore, it can be seen that the electromagnetic interference shielding film with heterogeneous stacking of metal and MXene improves SE not by the thickness of the MXene layer, but by the generation of AMIR due to the mismatch in electrical conductivity between the copper thin film and the MXene layer at the junction between the copper thin film and the MXene layer.

[0177] Measurement Example 3

[0178] FIG. 15 is a graph showing the average SE and electrical resistance values ​​measured according to the presence or absence of the passivation layer in Preparation Examples 1-7 and 1-10.

[0179] Referring to FIG. 15, the copper thin film and MXene layer are susceptible to oxidation, which can affect shielding stability. Therefore, it is more desirable to form a passivation layer on the uppermost metal thin film of a heterogeneously stacked multilayer metal-MXene electromagnetic interference shielding film, and the passivation layer has a thin thickness of 20 μm or less to maintain the bending rigidity of the electromagnetic interference shielding film while preventing a decrease in shielding performance due to humidity, discoloration, and mechanical cracking.

[0180] FIG. 16 shows images of the surface of an electromagnetic interference shielding film observed over time with and without a passivation layer, where (a) to (d) relate to Preparation Example 1-7 without a passivation layer and (e) to (h) relate to Preparation Example 1-10 with a passivation layer, and FIG. 17 shows graphs representing the average SE curves accordingly. FIG. 16 and FIG. 17 were observed at pristine, 49 h, 324 h, and 420 h, respectively; Preparation Example 1-10 shows almost no discoloration compared to the initial state, and the average SE total The price did not drop.

[0181] Therefore, through FIGS. 16 and 17, it can be seen that shielding performance can be maintained when a passivation layer is formed.

[0183] Measurement Example 4

[0184] Figure 18 shows graphs measuring malfunctions caused by electromagnetic noise in a Bluetooth speaker. Under conditions where the IC chip of a USB 3.0 drive generating EM noise is passive and communication between a Bluetooth dongle and a speaker is obstructed, the sound amplitude integrity was verified in the case where aluminum foil was covered and in the case where the shielding film of Manufacturing Example 1-10 was formed.

[0185] Figure 19 is a graph showing the effect of shielding on the integrity of the Bluetooth signal of Figure 18.

[0186] Referring to FIGS. 18 and 19, (c) effectively mitigated electromagnetic waves and reduced noise compared to (a) and (b) of FIGS. 18, and this could be confirmed through FIGS. 19.

[0188] Accordingly, according to the present invention described above, the electromagnetic interference shielding film with heterolayered metal-MXene is manufactured with a thinner thickness compared to conventional porous electromagnetic interference shielding films by inserting a non-porous MXene layer into a metal thin film layer, thereby eliminating constraints on the minimum thickness required for pore formation, and possesses excellent uniformity and processing compatibility. Therefore, the electromagnetic interference shielding film with heterolayered metal-MXene has low bending stiffness due to its thin thickness and can be easily formed on the surface of various types of IC chips. Furthermore, since it does not include the step of additionally forming a pore structure within the electromagnetic interference shielding film with heterolayered metal-MXene, it exhibits excellent spatial uniformity and reproducibility, preventing a decrease in passivation yield and providing excellent shielding performance.

[0189] A heterogeneous stacked metal-MXene electromagnetic interference shielding film can achieve excellent electromagnetic shielding efficiency because an electromagnetic wave confinement wall is formed at the interface where the metal thin film layer and the MXene layer are bonded due to high reflection loss caused by the conductivity mismatch between the metal thin film layer and the MXene layer, and the interface and the MXene flake dipoles absorb reflected waves to generate effective AMIR (Absorption during multiple internal reflections) within the electromagnetic interference shielding film.

[0190] The electromagnetic interference shielding film with heterogeneous stacking of metal-MXene may have a multilayer stacked structure in which a metal thin film layer and a MXene layer are stacked in sequence, and may have excellent shielding performance as the number of junctions between the metal thin film layer and the MXene layer increases. Explanation of the symbols

[0191] 101, 102, 103, 104, 105: Metal thin films 201, 202, 203, 204: MXene layer

Claims

Claim 1 An electromagnetic interference shielding film formed by heterostacking a metal-MXene sandwich structure comprising: a lower metal thin film; an MXene located on the metal; and an upper metal thin film for electromagnetic shielding located on the MXene and having the same material as the lower metal thin film; wherein the lower metal thin film and the upper metal thin film induce absorption during multiple internal reflections (AMIR) by the dipole of the MXene surface at the interface in contact with the MXene. Claim 2 In claim 1, the electromagnetic interference shielding film having heterogeneously stacked metal-MXene is characterized by having a multilayer structure containing two or more layers of MXene through the repeated stacking of a metal thin film and MXene. Claim 3 In paragraph 2, the electromagnetic interference shielding film having heterolayered metal-MXene is characterized by having a thickness of 0.4 μm to 2 μm. Claim 4 In claim 3, the electromagnetic interference shielding film having heterolayered metal-MXene is characterized in that one layer of the MXene thin film layer has a thickness of 0.2 μm or less. Claim 5 In claim 4, the electromagnetic interference shielding film having heterolayered metal-MXene is characterized by having a shielding effectiveness (SE) of 69.2 (±1.6) dB or higher. Claim 6 An electromagnetic interference shielding film having heterolayered metal-MXene, characterized in that, in claim 1, the metal thin film is selected from the group consisting of metal materials including Cu, Au, and Ag. Claim 7 A method for manufacturing an electromagnetic interference shielding film having heterolayered metal-MXene, comprising: a step of forming a sacrificial layer on a substrate; a step of depositing a lower metal thin film on the sacrificial layer; a step of coating an interface adhesion promoter on the lower metal thin film; a step of coating a MXene layer on the lower metal thin film coated with the interface adhesion promoter; a step of coating an interface adhesion promoter on the MXene layer; and a step of depositing an upper metal thin film on the MXene layer coated with the interface adhesion promoter. Claim 8 A method for manufacturing an electromagnetic interference shielding film having heterogeneously stacked metal-MXene, characterized in that, in claim 7, the MXene layer and the upper metal thin film have a multilayer structure including two or more layers of the MXene layer through repeated stacking. Claim 9 A method for manufacturing a heterogeneously laminated electromagnetic interference shielding film of metal-MXene according to claim 7, characterized in that a passivation layer is additionally formed on an upper metal thin film of the heterogeneously laminated metal-MXene. Claim 10 A method for manufacturing an electromagnetic interference shielding film having heterolayered metal-MXene, characterized in that, in claim 7, the heterolayered metal-MXene electromagnetic interference shielding film has a thickness of 2 µm or less. Claim 11 A method for manufacturing an electromagnetic interference shielding film having heterogeneously stacked metal-MXene, characterized in that, in claim 7, the MXene layer has a thickness of 0.2 μm or less per layer. Claim 12 A method for manufacturing a heterolayered electromagnetic interference shielding film of metal-MXene according to claim 7, characterized in that the heterolayered electromagnetic interference shielding film of the metal-MXene has an electromagnetic shielding efficiency (SE) of 69.2 (±1.6) dB or higher. Claim 13 A method for manufacturing an electromagnetic interference shielding film having heterolayered metal-MXene, characterized in that, in claim 7, the metal thin film layer is selected from the group consisting of Cu, Au, Ag, and TiOx.

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