Method for manufacturing flexible metal laminated film for ultrahigh frequency and flexible metal laminated film manufactured thereby

Abstract

The present invention relates to a method for manufacturing a flexible metal laminated film and, specifically, to a method for manufacturing a flexible metal laminated film, comprising the steps of: preparing a low-dielectric material; heat-treating the low-dielectric material; primarily surface-treating the surface of the heat-treated low-dielectric material; secondarily surface-treating the primarily surface-treated low-dielectric material; sequentially performing surface treatment on the secondarily surface-treated low-dielectric material up to the n-th surface treatment; forming a first metal layer on the surface of the low-dielectric material on which the n-th surface treatment has been completed; forming a second metal layer on the first metal layer; and forming a metal electrode layer on the second metal layer. Thus, the method ensures stability between the low-dielectric material and the metal electrode layer.

Description

Method for manufacturing flexible metal laminate film for ultra-high frequency and flexible metal laminate film manufactured thereby

[0001] The present invention relates to a method for manufacturing a flexible metal laminate film, and more particularly, to a method for manufacturing a flexible metal laminate film for ultra-high frequencies to ensure stability between a low-k material and a metal electrode layer.

[0002] With the recent commercialization of 5G communications, Korea is building ultra-high-speed communication infrastructure using frequency bands in the 3.5 GHz and 28 GHz range. As frequency bands increase, signal loss between communication modules in mobile devices (e.g., smartphones, smartwatches) and automobiles becomes more frequent.

[0003] Signal loss occurs primarily in antennas that transmit and receive signals, and the inherent properties of the insulator (dielectric constant, dielectric loss) of the circuit that constitutes the antenna have a significant impact on signal loss.

[0004] In order to minimize signal loss, the lower the dielectric constant and dielectric loss of the insulator, the more advantageous it is. In the existing 4G communication, PI (polyimide) film was used as an insulator, but with the advent of 5G communication, low-dielectric materials are being developed or discovered to manufacture circuit boards.

[0005] As a representative example, Apple uses Liquid Crystal Polymer (LCP), and LCP has a dielectric constant of 3.3, which is superior to PI, which has a dielectric constant of 3.9.

[0006] However, since LCP materials are mainly produced in Japan and the production cost is higher than that of existing PI, domestic companies are producing antennas using Modified PI (hereinafter referred to as MPI).

[0007] MPI is a material that lowers the dielectric constant by adding fluorine to conventional PI. Depending on the fluorine content, the dielectric constant can be adjusted to 2.7 to 3.1. Its production cost is lower than that of LCP, and it exhibits superior adhesion when forming or bonding copper electrodes compared to LCP. However, in actual usage environments, MPI exhibits higher signal loss than LCP, but this is overcome through circuit design changes.

[0008] When moving from 5G to 6G communication, communication will be conducted in the ultra-high frequency range of 100 GHz, and in this case, it will be inevitable to use fluororesin as an insulator.

[0009] Fluoropolymers have the lowest dielectric constants among polymers. Polytetrafluoroethylene (PTFE), for example, has a very low dielectric constant of 2.1 and boasts the best dielectric loss characteristics among fluoropolymers. However, despite their superior dielectric properties, fluoropolymers do not react well with other substances due to the strong covalent bonds between carbon and fluorine (CF), which form their basic linking structure. This hinders the formation of a strong bond between the conductive metal electrode layer and the insulating layer when manufacturing flexible metal laminate films.

[0010] When electroplating is performed after PVD deposition on standard PTFE, peeling occurs during the plating process, and peel strength measurements after plating are low, typically below 1 N / cm. These characteristics make fluoropolymers highly chemically resistant, allowing them to be used in acidic and alkaline solutions. Therefore, if they can form a strong bond with the electrode layer, they are expected to be used in circuit boards requiring chemical resistance, such as sensors.

[0011] In order to improve adhesion of these fluororesins, various surface treatments are performed, and for example, methods such as ion beam and electron beam plasma in a vacuum have been used.

[0012] According to a recent reference, Adhesive-free adhesion between heat-assisted plasma-treated fluoropolymers (PTFE, PFA) and plasma-jet-treated polydimethylsiloxane (PDMS) and its application, heat-assisted plasma (HAP) surface treatment was applied to improve the adhesion between PTFE and PDMS. HAP treatment uses a plasma jet, and when the power is high, the surface temperature rises above the glass transition temperature (Tg) simultaneously with surface modification. At this time, the PTFE film has the effect of restoring the mechanical strength of the surface weakened by the skiving process during the production process. The restored surface has high hardness and strength, and when bonded to PDMS, the PTFE surface, not the interface between PTFE and PDMS, is peeled off, resulting in a higher peel strength than the surface weakened by skiving.

[0013] In order to apply the above process to a large-area roll product, multiple plasma torches must be aligned in a single row, and at this time, when overlapping the torches, the ions to be irradiated must be aligned so that they are evenly distributed in the width direction based on the ion distribution curve of the plasma. If not, a quality deviation will occur in the width direction of the film. In addition, when a thin film of about 50㎛ is exposed to a high temperature and a roll-to-roll process is performed, there was a problem that elongation occurred in the length direction, resulting in wrinkles in the length direction.

[0014] The present invention is intended to solve the above problems, and the present invention provides a method for manufacturing a flexible metal laminate film for ultra-high frequency to ensure stability between a low-k material and a metal electrode layer.

[0015] The above and other objects and advantages of the present invention will become apparent from the following description of preferred embodiments.

[0016] The above object can be achieved by a method for manufacturing a flexible metal laminated film for ultra-high frequency, comprising the steps of: preparing a low-k dielectric material; heat-treating the low-k dielectric material; first surface-treating the surface of the heat-treated low-k dielectric material; second surface-treating the low-k dielectric material that has been surface-treated first; sequentially performing surface treatments up to n times on the low-k dielectric material that has been surface-treated secondarily; forming a first metal layer on the surface of the low-k dielectric material that has been surface-treated secondarily; forming a second metal layer on the first metal layer; and forming a metal electrode layer on the second metal layer; wherein the n times are 3 to 5.

[0017] The above low-k dielectric material is characterized in that it is a polymer containing elements of carbon (C), hydrogen (H), and oxygen (O), or a polymer containing elements of carbon (C), hydrogen (H), and oxygen (O) and further containing nitrogen (N) or fluorine (F).

[0018] The above low dielectric material is selected from the group consisting of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), polyimide (PI), modified polyimide (MPI), polytetrafluoroethylene (PTFE), polyoxymethylene (PFA), fluorinated ethylene propylene (FEP), ethylene tetrafluoro ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), glass fiber, and polytetrafluoro ethylene (PTFE). It is characterized by including at least one selected type.

[0019] The above heat treatment is characterized in that it is performed at a temperature of 80 to 150°C using an infrared heater (IR heater).

[0020] The above primary surface treatment is characterized in that it is performed using a linear ion beam with an ionized active gas or inert gas as a reaction gas. The above primary surface treatment is characterized in that it is performed using O2, N2, H2 or Ar gas as a reaction gas.

[0021] The above second to n-th surface treatments are characterized in that they are performed using a linear ion beam with an ionized active gas as a reaction gas. The above second to n-th surface treatments are characterized in that they are performed using O2, N2, or H2 gas as a reaction gas.

[0022] The ion dose density in the above linear ion beam is 1x10 -14 5x10 - 17 dose / cm 2 It is characterized by being composed of a region of . It is characterized by being composed of a region of 0.5 to 2.0 kV of the voltage input from the linear ion beam.

[0023] The step of forming the first metal layer is characterized by using at least one metal selected from the group consisting of copper (Cu), nickel (Ni), nickel chromium alloy (NiCr), and nickel copper alloy (NiCu), and in the case of a nickel alloy, the nickel content is characterized by being 70% or more.

[0024] The step of forming the first metal layer is characterized by performing a physical vapor deposition (PVD) or thermal evaporation process.

[0025] The step of forming the second metal layer is characterized by using at least one metal selected from the group consisting of copper (Cu), aluminum (Al), silver (Ag), gold (Au), platinum (Pt), and alloys thereof. The step of forming the second metal layer is characterized by performing a physical vapor deposition (PVD) or evaporation process.

[0026] The above metal electrode layer is characterized in that it is formed by performing electroplating using a metal such as gold, silver, cobalt, aluminum, iron, nickel, chromium or copper.

[0027] According to the present invention, a method for manufacturing a flexible metal laminate film for ultra-high frequency is provided to ensure stability between a low-k material and a metal electrode layer.

[0028] Specifically, according to the present invention, by performing heat treatment on a low-k material to cause outgassing and change the surface shape, and performing primary, secondary, and n-th surface treatments using a low-energy ion beam to increase the surface energy of the material, the reactivity between different materials can be improved. In addition, by performing a multilayer conductive metal thin film deposition and plating process, the adhesion between the surface-treated low-k material, which is an insulator, and the metal electrode, which is a conductor, can be increased, and the bonding stability can be imparted.

[0029] The ultra-high frequency flexible multilayer metal laminate film manufactured by the method for manufacturing the ultra-high frequency flexible metal laminate film of the present invention can be applied to, for example, AiP (Antenna in Packaging) for 5G and 6G communications, sensors for autonomous vehicles, etc. As a result, it can have the effect of minimizing signal loss applied to various communication devices. However, the application examples of the ultra-high frequency flexible multilayer metal laminate film are not limited to this.

[0030] However, the effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

[0031] Figure 1 is a flow chart sequentially showing a method for manufacturing a flexible metal laminate film according to one embodiment of the present invention.

[0032] Figure 2 is a schematic diagram showing a flexible metal laminate film structure manufactured according to one embodiment of the present invention.

[0033] Figure 3 is a schematic diagram showing a flexible metal laminate film structure manufactured according to another embodiment of the present invention.

[0034] Figure 4 is a drawing showing the results of surface roughness measurement according to Experimental Example 1 of the present invention.

[0035] Figure 5 is a drawing showing the results of peel strength measurement according to Experimental Example 2 of the present invention.

[0036] Figure 6 is a drawing showing the XPS measurement results according to Experimental Example 3 of the present invention.

[0037] Figure 7 is a diagram showing the bonding energy range due to chemical bonding.

[0038] Figure 8 is a graph showing the results of peel strength measurement according to ion dose density according to Experimental Example 4.

[0039] Figure 9 is a graph showing the results of measuring peel strength according to ion beam pressure voltage in Experimental Example 5.

[0040] Hereinafter, the present invention will be described in detail with reference to examples and drawings. These examples are provided solely as examples to more specifically illustrate the present invention, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.

[0041] Additionally, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and in case of conflict, the description in this specification, including definitions, shall prevail.

[0042] To clearly explain the invention proposed in the drawings, irrelevant parts have been omitted, and similar parts have been designated with similar drawing reference numerals throughout the specification. Furthermore, when a part is said to "include" a component, this does not mean that other components are excluded, but rather that other components may be included, unless otherwise specifically stated. Furthermore, the term "part" described in the specification refers to a single unit or block that performs a specific function.

[0043] The identifiers (1, 2, etc.) for each step are used for convenience of explanation and do not describe the order of each step. Each step may be performed in a different order than stated unless the context clearly indicates a specific order. In other words, each step may be performed in the same order as stated, may be performed substantially simultaneously, or may be performed in the opposite order.

[0044]

[0045] Hereinafter, implementation examples and embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention may not be limited to these implementation examples and embodiments and drawings.

[0046]

[0047] FIG. 1 is a flowchart sequentially showing a method for manufacturing a flexible metal laminate film according to one embodiment of the present invention, and FIG. 2 is a schematic diagram showing a structure of a flexible metal laminate film manufactured according to one embodiment of the present invention.

[0048] Referring to FIGS. 1 and 2 together, the method for manufacturing the flexible metal laminate film includes the steps of: preparing a low-k material; heat-treating the low-k material (S10); first surface-treating the surface of the heat-treated low-k material (S20); second surface-treating the low-k material that has been surface-treated first (S30); second surface-treating the low-k material that has been surface-treated secondarily (S40); sequentially performing surface treatments up to n times on the low-k material that has been surface-treated secondarily (S40); forming a first metal layer on the surface of the low-k material that has been surface-treated n times (S50); forming a second metal layer on the first metal layer (S60); and forming a metal electrode layer on the second metal layer (S70).

[0049]

[0050] First, a low-k dielectric material (100) can be prepared.

[0051] The low-k dielectric material (100) of the present invention may be, for example, a polymer containing elements of carbon (C), hydrogen (H), and oxygen (O), or may be composed of a polymer containing elements of carbon (C), hydrogen (H), and oxygen (O) and further containing nitrogen (N) or fluorine (F).

[0052] The above low dielectric material (100) may be, for example, polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), polyimide (PI), modified polyimide (MPI), polytetrafluoroethylene (PTFE), polyoxymethylene (PFA), fluorinated ethylene propylene (FEP), ethylene tetrafluoro ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), glass fiber, and polytetrafluoro ethylene (PTE). It may include at least one selected from the group consisting of PTFE.

[0053] The above polytetrafluoroethylene (PTFE) may include, for example, ceramics including Al2O3, AlN, Si3N4, SiO2, or BN, or carbon.

[0054] It is preferable that the thickness of the above low-k dielectric material (100) be formed to be, for example, 25 to 200 ㎛.

[0055]

[0056] Next, the low-k dielectric material (100) can be heat-treated (S10). The heat treatment can be performed for the purposes of removing impurities remaining inside and outside the low-k dielectric material (100), controlling the shape of the surface, improving the peel strength, etc. The heat treatment can have effects such as outgassing inside the low-k dielectric material (100), increasing the movement of surface polymer chains, changing the surface shape of the polymer, and changing the physical properties.

[0057] It is preferable that the above heat treatment be performed using an infrared heater (IR heater) provided at the front end of a primary surface treatment device for the primary surface treatment performed later.

[0058] The above heat treatment may vary depending on the type of the low-k dielectric material (100), but is preferably performed at a temperature of, for example, 80 to 150°C. If the temperature of the heat treatment exceeds 150°C, the low-k dielectric material (100) may be heated more than necessary, causing shrinkage or expansion of the material, resulting in a problem of deterioration in quality.

[0059]

[0060] Next, the surface of the heat-treated low-k dielectric material (100) can be subjected to primary surface treatment (201) (S20).

[0061] The above first surface treatment is performed by using a first surface treatment device, specifically, a low-energy ion beam, in a state where the movement of the polymer chains of the low-k material has been increased by the heat treatment described above, thereby obtaining hydrophilic functional groups on the polymer surface.

[0062] The above primary surface treatment (201) can be performed using a low-energy ion beam, specifically, a linear ion beam, using an ionized active gas or inert gas as a reaction gas. The surface treatment using an ion beam can be performed by irradiating the surface of the low-k dielectric material (100) with an ion beam containing a reaction gas accelerated to an energy of a specific range. For example, the above primary surface treatment can be performed using O2, N2, H2, or Ar as a reaction gas.

[0063] The injection amount of the above reaction gas may be, for example, 1 to 100 sccm (Standard Cubic Centimeter per Minute), preferably 50 to 100 sccm, and more preferably 60 to 80 sccm, and within this range, there is an effect of stably irradiating the surface of a low-k material with an ion beam.

[0064] The irradiation time of the above ion beam is not particularly limited and can be appropriately adjusted depending on the purpose.

[0065] The ion dose density irradiated on the surface of the low-k material through the above low-energy ion beam is 1x10 -14 5x10 -17 dose / cm 2 It can be adjusted to consist of the following areas.

[0066] The voltage input to the above low-energy ion beam can be applied in the range of 0.5 to 2.0 kV.

[0067] When ion beams are irradiated under the conditions described above, the ion beam irradiation effect and the surface modification effect can be maximized, and by increasing the peeling strength, the effect of increasing the contact stability between the low-k material and the metal electrode layer can be exhibited.

[0068]

[0069] Next, the low-k dielectric material that has been subjected to primary surface treatment (201) can be subjected to secondary surface treatment (S30).

[0070] The above secondary surface treatment can be performed using a low-energy ion beam, i.e., a linear ion beam, with an ionized active gas as the reaction gas. Specifically, the above secondary surface treatment can be performed using O2, N2, or H2 gas as the reaction gas.

[0071] Next, the secondary surface-treated low-k dielectric material can be sequentially surface-treated up to the nth time (S40). In other words, the nth surface treatment (200) can be performed, which means that the surface of the secondary surface-treated low-k dielectric material is surface-treated again in a series of multiple times. In this case, the nth surface treatment (200) can mean a surface treatment performed at least three times, specifically, three to five times.

[0072] The method for performing the above secondary surface treatment and nth surface treatment can be performed in the same manner as the primary surface treatment (201), except that an inert gas is used in the reaction gas.

[0073] In the above first, second and nth surface treatments, the ion dose density irradiated on the surface of the low-k material through a low-energy ion beam is 1x10 -14 5x10 - 17 dose / cm 2 It can be adjusted to consist of the following areas.

[0074] In the above, 2nd and nth surface treatments, the voltage input to the low-energy ion beam can be applied in the range of 0.5 to 2.0 kV.

[0075] When ion beams are irradiated under the conditions described above, the ion beam irradiation effect and the surface modification effect can be maximized, and by increasing the peeling strength, the effect of increasing the contact stability between the low-k material and the metal electrode layer can be exhibited.

[0076]

[0077] In the present invention, by performing a heat treatment on a low-k material and then sequentially performing a first surface treatment and a second to nth surface treatment, the interaction of chemical functional groups formed on polymer chains is induced, thereby increasing surface energy and increasing the role of polymer chains on the surface, thereby stably increasing the movement of polymer chains and preventing the flow of polymer chains present on the surface, thereby significantly improving the adhesion to different materials or substances through a change in surface shape.

[0078] Accordingly, when forming various types of conductive metal layers on the surface formed through the aforementioned heat treatment and surface treatment, excellent stability (high temperature, moisture, etc.) between the heterogeneous materials of the low-k material (e.g., polymer) and the metal electrode layer can be secured.

[0079]

[0080] Next, a first metal layer (300) can be formed on the surface of the low-k dielectric material on which n-th surface treatment (200) has been completed (S50).

[0081] The first metal layer (300) may use at least one metal selected from the group consisting of copper (Cu), nickel (Ni), nickel chromium alloy (NiCr), and nickel copper alloy (NiCu). In the case of the nickel alloy, it is preferable that the nickel content be 70% or more.

[0082] As a method for forming the above first metal layer (300), deposition can be performed through a physical vapor deposition (PVD) or thermal evaporation process.

[0083] It is preferable that the deposition thickness of the first metal layer (300) be formed to be, for example, 10 to 30 nm.

[0084]

[0085] Next, a second metal layer (400) can be formed on the first metal layer (300) (S60).

[0086] The step of forming the second metal layer (400) may use one or more metals selected from the group consisting of copper (Cu), aluminum (Al), silver (Ag), gold (Au), platinum (Pt), and alloys thereof.

[0087] The type of metal constituting the second metal layer (400) may be the same as or different from the type of metal constituting the first metal layer (300).

[0088] As a method for forming the above second metal layer (400), deposition can be performed through a physical vapor deposition (PVD) or thermal evaporation process.

[0089] It is preferable that the deposition thickness of the second metal layer (400) be formed to be, for example, 100 to 500 nm.

[0090]

[0091] Next, a step (S80) of forming a metal electrode layer (500) on the second metal layer (400) is included.

[0092] The above metal electrode layer (500) can be formed, for example, using roll-to-roll electroplating or electroless plating equipment. The electroplating can be performed using a method commonly used in this technical field.

[0093] When performing the above electroplating, a person skilled in the art can select an appropriate metal according to the metal texture to be implemented, and for example, it can be gold, silver, cobalt, aluminum, iron, nickel, chromium or copper, and preferably, copper can be used, but is not limited thereto.

[0094] The thickness of the above metal electrode layer (500) can be formed to be 2 to 20 μm.

[0095]

[0096] Meanwhile, the flexible metal laminate film according to one embodiment of the present invention may further form a protective layer on the metal electrode layer. The protective layer may be formed of an organic material to prevent oxidation and corrosion of the metal electrode layers.

[0097]

[0098] A flexible metal laminate film structure manufactured according to one embodiment of the present invention may include: a heat-treated low-k dielectric material (100); a first surface treatment layer (201) formed on a surface of the heat-treated low-k dielectric material (100); an n-th surface treatment layer (200) formed on the first surface treatment layer (201); a first metal layer (300) formed on the n-th surface treatment layer (200); a second metal layer (400) formed on the first metal layer (300); and a metal electrode layer (500) formed on the second metal layer (400).

[0099] At this time, the term “surface treatment layer” is described to facilitate explanation by illustrating the layer structure, and it is preferable to interpret the meaning of the “surface treatment layer” as meaning the state of the surface-treated coating film.

[0100]

[0101] Figure 3 is a schematic diagram showing a flexible metal laminate film structure manufactured according to another embodiment of the present invention.

[0102] Referring to FIG. 3, a flexible metal laminate film structure according to another embodiment of the present invention includes: a heat-treated low-k dielectric material (100); a first surface treatment layer (201) formed on a surface of the heat-treated low-k dielectric material (100); an n-th surface treatment layer (200) formed on the first surface treatment layer (201); a first metal layer (300) formed on the n-th surface treatment layer (200); a second metal layer (400) formed on the first metal layer (300); and a metal electrode layer (500) formed on the second metal layer (400).

[0103] It may further include a structure of a first surface treatment layer (90) formed on the lower surface of the heat-treated low-k dielectric material (100); an n-th surface treatment layer (91) formed on the first surface treatment layer (90); a first metal layer (80) formed on the n-th surface treatment layer (91); a second metal layer (70) formed on the first metal layer (80); and a metal electrode layer (500) formed on the second metal layer (70).

[0104] In other words, according to another embodiment of the present invention, although the process of performing heat treatment and surface treatment on the upper surface of the low-k dielectric material (100) has been described above, by performing the same process on the lower surface of the low-k dielectric material (100), a flexible multilayer metal laminate film can also be formed in a composite structure.

[0105]

[0106] In addition to the structure described above, it is self-evident that any number of layers, components, structures, manufacturing processes, etc. commonly used in the field can be included by design modification.

[0107]

[0108] According to one embodiment of the present invention, a method for manufacturing a flexible metal laminate film for ultra-high frequency is provided to ensure stability between a low-k material and a metal electrode layer.

[0109] Specifically, according to the present invention, by performing heat treatment on a low-k material to cause outgassing and change the surface shape, and performing primary, secondary, and n-th surface treatments using a low-energy ion beam to increase the surface energy of the material, the reactivity between different materials can be improved. In addition, by performing a multilayer conductive metal thin film deposition and plating process, the adhesion between the surface-treated low-k material, which is an insulator, and the metal electrode, which is a conductor, can be increased, and the bonding stability can be imparted.

[0110] The ultra-high frequency flexible multilayer metal laminate film manufactured by the method for manufacturing the ultra-high frequency flexible metal laminate film of the present invention can be applied to, for example, AiP (Antenna in Packaging) for 5G and 6G communications, sensors for autonomous vehicles, etc. As a result, it can have the effect of minimizing signal loss applied to various communication devices. However, the application examples of the ultra-high frequency flexible multilayer metal laminate film are not limited to this.

[0111]

[0112] Hereinafter, the composition and resulting effects of the present invention will be described in more detail through specific examples and comparative examples. However, these examples are intended to more specifically illustrate the present invention, and the scope of the present invention is not limited to these examples.

[0113]

[0114] [Example 1]

[0115] For the low-k material, PTFE film with a thickness of 150 μm, heat treatment was performed at 150°C for 5 minutes using an infrared heater. Then, a linear ion beam was used on the surface of the film in an Ar gas atmosphere with an ion dose density of 5×10 -14 dose / cm 2 The first surface treatment was performed with . Then, in a N2 gas atmosphere, the ion dose density was 5×10 -14 dose / cm 2 Secondary surface treatment was performed. For both primary and secondary surface treatments, the input voltage was 1.0 kV.

[0116]

[0117] [Example 2]

[0118] Except for the contents described below, the same procedure as in Example 1 described above was performed. The third surface treatment was performed once more using the same method as the second surface treatment.

[0119]

[0120] <Experimental Example 1: Surface roughness measurement according to heat treatment>

[0121] After performing Example 1, surface roughness changes according to temperature were measured to confirm changes in surface morphology according to heat treatment temperature. Surface roughness was measured using a SE800 model (contact surface roughness measuring instrument) from Kosaka Laboratory Ltd. The results are shown in Fig. 4.

[0122] Referring to Figure 4, experimental groups 4, 5, and 6 have input voltage of 1.0 kV, primary Ar gas, and ion dose density of 5x10 - 14 dose / cm 2 -, secondary N2 gas ion dose density 5x10 - 14 dose / cm 2 After surface treatment, heat treatment was performed on a hot plate at 150℃, 200℃, and 250℃ for 5 minutes, respectively. The average roughness (Ra) was 0.371㎛, 0.452㎛, and 0.360㎛, respectively. This was half the average roughness (Ra) of 0.730㎛ immediately after surface treatment. In addition, since there was no significant difference in the decrease in surface roughness even when the temperature increased from 150℃, the pre- and post-heat treatments were performed at a fixed temperature of 150℃.

[0123] Meanwhile, in order to confirm the effect of heat treatment performed before surface treatment, the control group (Bare PTFE) was heat treated on a hot plate at 150℃ for 5 minutes and then surface treated under the same surface treatment conditions as described above (Experimental Group 3). As a result, it was confirmed that although it was slightly higher than the control group (Bare PTFE), it secured values ​​of Ra 0.188㎛ and Rz 0.692㎛, which were much lower than the conditions of Experimental Group 7, which only underwent surface treatment, and Experimental Groups 4, 5, and 6, which underwent heat treatment after surface treatment.

[0124]

[0125] <Experimental Example 2: Measurement of peel strength according to heat treatment>

[0126] After performing Example 1, a peel strength measurement experiment was conducted using the same surface treatment and heat treatment conditions as the surface roughness measurement experiment of Experimental Example 1 described above to confirm the effect of heat treatment on peel strength.

[0127] The specific experimental method was as follows: After performing all of Example 1, Cu was deposited to a thickness of 200 nm, and then an 18 μm thick Cu foil layer was formed through electroplating at a current density of 2 ASD for 50 minutes (Experimental Group 3). In addition, Experimental Group 2, which performed surface treatment first and then heat treatment, and Experimental Group 1, which did not perform heat treatment before or after surface treatment, were also set as comparison groups. For the experimental groups, the 90-degree peel strength was measured according to the JIS C 6481 standard using the LS1 equipment of LLOYD. The measurement results are shown in Fig. 5.

[0128] Referring to Fig. 5, when only surface treatment was applied without heat treatment, a relatively low peeling strength of approximately 5 N / cm was confirmed. In addition, when heat treatment was performed after surface treatment, as in Experimental Group 2, it was confirmed that the highest peeling strength of approximately 6 N / cm was observed, and when heat treatment was performed before surface treatment, as in Experimental Group 3, it was confirmed that the highest peeling strength of approximately 7 N / cm was observed.

[0129]

[0130] <Experimental Example 3: Confirmation of surface modification effect according to surface treatment level>

[0131] In order to confirm the surface modification effect according to the first, second, and nth surface treatments according to one embodiment of the present invention, untreated (control group), first surface treatment (comparative example), first and second surface treatments (Example 1), and first, second, and tertiary surface treatments (Example 2) were set as experimental groups. The conditions for each surface treatment for the experimental group were an input voltage of 1.0 kV, a first Ar gas, and an ion dose density of 5x10 - 14 dose / cm 2 , secondary N2 gas ion dose density 5x10- 14 dose / cm 2 , tertiary N2 gas ion dose density 5x10 -14 dose / cm 2 Surface treatment was performed.

[0132] For each experimental group, the chemical bonding state of the material surface was confirmed by measuring X-ray photoelectron spectroscopy (XPS). The results are shown in Fig. 6, and Fig. 7 is a diagram showing the binding energy range due to chemical bonding.

[0133]

[0134] Referring to FIGS. 6 and 7 together, the binding energy before surface treatment had a peak value at 292 eV, which was confirmed to be a typical chemical bond of PTFE having CF, C-F2 bonds.

[0135] Afterwards, as the number of surface treatments increases from the 1st surface treatment (comparative example), the 1st and 2nd surface treatments (Example 1), to the 1st, 2nd and 3rd surface treatments (Example 2), it can be confirmed that the peak at 292 eV gradually decreases and a peak value of 284 to 285 eV is formed, which can be interpreted as the CF bond being broken and the bonds such as C-, CO, and CN being formed. In addition, it can be confirmed that when the 3rd surface treatment is performed, all of the CF bonds at 292 eV disappear and the bonds such as C-, CO are formed, lowering the surface energy. This can be interpreted as having the effect of further enhancing the bonding strength with the metal layer formed in the next step.

[0136]

[0137] <Experimental Example 4: Measurement of Peel Strength According to Ion Dose Density>

[0138] An experiment was conducted to measure the peel strength according to the ion dose density. After performing the heat treatment of Example 1, the input voltage was fixed at 1.0 kV and the ion dose density was 9x10 -3 6x10 -17 dose / cm 2 After surface treatment by changing to , a first NiCr metal layer with a thickness of 15 nm and a second Cu metal layer with a thickness of 200 nm were formed, and then electroplated to a thickness of 18 μm. Afterwards, the 90° peel strength was confirmed through a method of measuring the peel strength according to JIS C 6481, and the results are shown in Fig. 8.

[0139] Referring to Figure 8, 9x10 - 13 dose / cm 2 A low peel strength of 2 N / cm was confirmed in , and 6x10 - 17 dose / cm 2 In , it was confirmed that deformation occurred due to overheating of the film. That is, 1x10 -14 5x10 - 17 dose / cm 2 In the ion dose density range, a satisfactory value of 7 N / cm or more of peel strength was obtained.

[0140]

[0141] <Experimental Example 5: Measurement of peel strength according to ion beam input voltage>

[0142] An experiment was conducted to measure the peel strength according to the ion beam input voltage. After performing the heat treatment of Example 1, the primary Ar gas and ion dose density were 5x10 in the voltage range of 0.4 to 2.5 kV. -14 dose / cm 2 , secondary N2 gas ion dose density 5x10 - 14 dose / cm 2 , tertiary N2 gas ion dose density 5x10 -14 dose / cm 2After surface treatment, a first NiCr metal layer with a thickness of 15 nm and a second Cu metal layer with a thickness of 200 nm were formed, and then electroplated to a thickness of 18 μm. The results were confirmed through a 90° peel strength measurement method according to JIS C 6481, and the results are shown in Fig. 9.

[0143] Referring to Fig. 9, the peel strength was low at 2 N / cm at an input voltage of 0.4 kV, and 7 to 10 N / cm at 0.5 to 2.0 kV, and the peel strength actually decreased to 6 N / cm at 2.5 kV. The decrease in peel strength at an input voltage of 2.5 kV is interpreted as being due to the high damage to the material surface. In other words, the targeted excellent peel strength characteristics could be secured at a voltage of 0.5 to 2.0 kV.

[0144]

[0145] The drawings and specifications disclose optimal embodiments. While specific terminology has been used herein, it is solely for the purpose of describing the present invention and is not intended to limit the scope of the invention as defined in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent embodiments are possible. Therefore, the true technical protection scope of the present invention should be defined by the technical spirit of the appended claims.

Claims

1. Step for preparing low-k materials; A step of heat treating the above low-k dielectric material; A step of performing primary surface treatment on the surface of a heat-treated low-k dielectric material; A step of performing a second surface treatment on a low-k dielectric material that has been first surface treated; A step of sequentially performing surface treatments up to n times on a low-k dielectric material that has been surface-treated for the second time; A step of forming a first metal layer on a low-k dielectric material surface on which n-th surface treatment has been completed; A step of forming a second metal layer on the first metal layer; and A step of forming a metal electrode layer on the second metal layer; including; A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above n-th order is 3rd to 5th.

2. In paragraph 1, The above low-k dielectric material is a polymer containing elements of carbon (C), hydrogen (H), and oxygen (O), or A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that it comprises a polymer containing the elements of carbon (C), hydrogen (H) and oxygen (O) and further containing nitrogen (N) or fluorine (F).

3. In paragraph 2, The above low dielectric material is selected from the group consisting of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), polyimide (PI), modified polyimide (MPI), polytetrafluoroethylene (PTFE), polyoxymethylene (PFA), fluorinated ethylene propylene (FEP), ethylene tetrafluoro ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), glass fiber, and polytetrafluoro ethylene (PTFE). A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that it includes at least one selected type.

4. In paragraph 1, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above heat treatment is performed at a temperature of 80 to 150°C using an infrared heater (IR heater).

5. In paragraph 1, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above first surface treatment is performed using a linear ion beam with an ionized active gas or inert gas as a reaction gas.

6. In paragraph 5, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above first surface treatment is performed using O2, N2, H2 or Ar gas as a reaction gas.

7. In paragraph 1, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above-mentioned second to n-th surface treatment is performed using a linear ion beam with an ionized active gas as a reaction gas.

8. In paragraph 7, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the above-mentioned second to n-th surface treatment is performed using O2, N2, or H2 gas as a reaction gas.

9. In paragraph 5 or paragraph 7, The ion dose density in the above linear ion beam is 1x10 -14 5x10 - 17 dose / cm 2 A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that it is composed of a region of .

10. In paragraph 9, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the voltage input from the linear ion beam is in the range of 0.5 to 2.0 kV.

11. In paragraph 1, The step of forming the first metal layer is characterized in that it uses at least one metal selected from the group consisting of copper (Cu), nickel (Ni), nickel chromium alloy (NiCr), and nickel copper alloy (NiCu). A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the nickel content is 70% or more in the case of a nickel alloy.

12. In paragraph 11, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the step of forming the first metal layer comprises performing a physical vapor deposition (PVD) or thermal evaporation process.

13. In paragraph 1, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the step of forming the second metal layer uses at least one metal selected from the group consisting of copper (Cu), aluminum (Al), silver (Ag), gold (Au), platinum (Pt) and alloys thereof.

14. In paragraph 13, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the step of forming the second metal layer comprises performing a physical vapor deposition (PVD) or evaporation process.

15. In paragraph 1, A method for manufacturing a flexible metal laminate film for ultra-high frequency, characterized in that the metal electrode layer is formed by performing electroplating using a metal such as gold, silver, cobalt, aluminum, iron, nickel, chromium or copper.

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