A copper clad laminate film and electronic device comprising the same

Abstract

Disclosed is a copper-clad laminate film and an electronic device including the same. The copper-clad laminate film includes a fluorine-containing base material; a tie layer disposed on the fluorine-containing base material; and a copper layer disposed on the tie layer, the tie layer being a metal layer including a metal having a metal-oxygen (M-O) bond dissociation energy of 400 kJ / mol or more or an alloy layer containing the metal, the tie layer having a thickness of 10 nm to 100 nm.

Description

Technical Field

[0001] This invention relates to a copper-clad laminate and an electronic device comprising the same. Background Technology

[0002] Copper-clad laminates are laminates of a substrate and conductive copper foil. With the trend towards miniaturization and lightweighting of electronic devices, the use of copper-clad laminates is increasing. Recently, due to the development of 5G mobile communication devices, signal transmission rates in the GHz band are becoming increasingly common. In response to this trend of higher signal frequencies, research is underway to improve the dielectric properties of substrates used in printed circuits or antenna devices at high frequencies. To meet these needs, methods of forming coatings on the surface of the substrate are being used. However, for these coated substrates, the coatability of the substrate surface and the room-temperature and / or high-temperature adhesion between the substrate and the copper foil may deteriorate. As a result, there is a trend towards reduced pattern etching and chemical resistance to acids or alkalis. Therefore, there is still a need for a copper-clad laminate that has improved dielectric properties at high frequencies, excellent coatability on the substrate surface, and excellent room-temperature and high-temperature adhesion between the substrate and the copper foil. Summary of the Invention

[0003] One aspect of this invention provides a copper-clad laminate that has improved dielectric properties at high frequencies, excellent coatability on the substrate surface, and excellent room-temperature and high-temperature adhesion between the substrate and the copper foil.

[0004] Another aspect of the present invention provides an electronic device including the copper-clad laminate.

[0005] In one aspect, the present invention provides a copper-clad laminate, comprising:

[0006] Fluorine-containing substrate;

[0007] A bonding layer disposed on the fluorinated substrate; and

[0008] A copper layer disposed on the tie layer,

[0009] The bonding layer is a metal layer comprising a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or an alloy layer containing such a metal.

[0010] The thickness of the bonding layer is 10 nm to 100 nm.

[0011] The water contact angle for the fluorinated substrate can be 120° or less.

[0012] The diiodomethane contact angle for the fluorinated substrate can be 90° or less.

[0013] The surface energy of the fluorinated substrate can be from 11 dyne / cm to 25 dyne / cm.

[0014] The fluorine content on the surface of the fluorine-containing substrate can be from 60 atomic% to 75 atomic%.

[0015] The bonding layer may include at least one metal selected from W, Ti, Sn, Cr, Al and Mo, or an alloy containing such metal.

[0016] The bonding layer may also include Ni, wherein the Ni content is 50% by weight or less.

[0017] The peel strength of the copper seed layer and copper plating layer relative to the polyimide substrate with the fluorine layer, measured after being placed at room temperature (25°C) for 3 days, can be 0.65 kgf / cm or higher.

[0018] The peel strength of the copper seed layer and copper plating relative to the polyimide substrate with the fluorine layer, measured after heat treatment at 150°C or higher two or more times and left to stand for 1 day, can be 0.35 kgf / cm or higher.

[0019] The thickness of the copper plating layer can be 12 μm or less.

[0020] According to another aspect of the invention,

[0021] An electronic device comprising the aforementioned copper-clad laminate is provided.

[0022] The electronic device may include an antenna device or an antenna cable. Attached Figure Description

[0023] Figure 1 This is a cross-sectional view of a copper-clad laminate according to an embodiment of the present invention.

[0024] Figure 2 This is a cross-sectional view of a double-sided copper-clad laminate according to another embodiment of the present invention. Detailed Implementation

[0025] The copper-clad laminate and electronic devices including the copper-clad laminate will now be described in detail with reference to embodiments and accompanying drawings of the present invention. Those skilled in the art should understand that these embodiments are given by way of example only to describe the invention more specifically, and the scope of the invention is not limited by these embodiments.

[0026] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of any conflict, this specification, including the definitions, shall prevail.

[0027] All methods and materials similar to or equivalent to those described and materials in this specification may be used in the implementation or testing of the present invention, wherein suitable methods and materials are described in this specification.

[0028] In this specification, unless otherwise stated, the term "comprising" means that other components may be further included, but not excluded.

[0029] In this specification, the term "and / or" refers to any and all combinations including one or more items relating to its description. In this specification, the term "or" means "and / or". The use of "at least one" or "one or more" before a component in this specification does not imply the inclusion of a list of all components or supplementation of the individual components described.

[0030] In this specification, "polyimide substrate" refers to both "polyimide substrate" and "substrate containing polyimide derivatives".

[0031] In this specification, when it is said that a component is set "on" another component, a component may be set directly on the other component, or there may be a component between these components. On the other hand, when it is said that a component is set "directly" on another component, there may be no intermediate component.

[0032] In electronic devices, antenna devices are typically fabricated by laminating a metal layer, such as copper foil, onto a substrate, which carries an electric current induced by a wireless signal.

[0033] Signal reception losses associated with an antenna can include losses due to the dielectric constant of the substrate and signal losses due to resistive physics as radio signals (electrical signals) flow through the metal layer. For wireless signals with high-frequency bands, the current induced by the wireless signal is more concentrated on the surface of the metal layer compared to wireless signals with relatively low-frequency bands. Furthermore, in copper-clad laminates, physical stress is generated in the copper foil in the bending areas of the antenna device, leading to cracks on its surface. As a result, transmission losses may occur. To address this issue, a method is being implemented that applies a material to the substrate surface to improve dielectric properties. However, this method suffers from problems such as poor coatability of the substrate surface and reduced adhesion between the substrate and the copper foil.

[0034] In view of this, the inventors of the present invention will propose the following copper-clad laminate.

[0035] According to an embodiment of the present invention, a copper-clad laminate includes: a fluorine-containing substrate; a bonding layer disposed on the fluorine-containing substrate; and a copper layer disposed on the bonding layer, wherein the bonding layer is a metal layer comprising a metal having a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or an alloy layer containing such metal, and the thickness of the bonding layer may be from 10 nm to 100 nm.

[0036] In this specification, "fluorinated substrate" refers to a substrate containing fluorine, specifically a substrate comprising a resin containing fluorine atoms. In this case, the substrate itself may be a resin containing fluorine atoms, or the resin containing fluorine atoms may be included in the substrate along with other resins, or it may be formed by surface treatment or coating of the substrate surface with a resin containing fluorine atoms. Examples of the inclusion of the resin containing fluorine atoms in the substrate along with other resins include all of the following: the resin containing fluorine atoms may be mixed with a polyimide resin to form the substrate, or the resin containing fluorine atoms may be coated on the surface of organic-inorganic particles included in the substrate, or the resin containing fluorine atoms may be mixed and included in the organic-inorganic particles themselves. Examples of formation by surface treatment or coating of the substrate surface with a resin containing fluorine atoms include all of the following: partial or complete surface treatment or coating of one or both sides of the substrate with a resin containing fluorine atoms. The copper layer may consist of layers consisting of a copper seed layer and a copper plating layer sequentially disposed.

[0037] The copper-clad laminate exhibits excellent room-temperature and high-temperature adhesion between the fluorine-containing substrate and the copper seed layer and copper plating layer, while also possessing improved dielectric properties at high frequencies and excellent coatability on the substrate surface.

[0038] Figure 1 This is a cross-sectional view of the copper-clad laminate 10 according to an embodiment of the present invention. Figure 2 This is a cross-sectional view of a double-sided copper-clad laminate 20 according to an embodiment of the present invention.

[0039] See Figure 1 According to an embodiment of the present invention, the copper-clad laminate 10 is sequentially configured with: a polyimide substrate 1 having a fluorine layer 5 as a fluorine-containing substrate, a bonding layer 2 on the polyimide substrate 1 having the fluorine layer 5, a copper seed layer 3, and a copper plating layer 4. See also Figure 2According to another embodiment of the present invention, the copper-clad laminate 20 is composed of a first surface 21 and a second surface 22. The first surface 21 is sequentially provided with: a polyimide substrate 11 having a fluorine layer 15 as a fluorine-containing substrate, a bonding layer 12, a copper seed layer 13, and a copper plating layer 14 on the polyimide substrate 11 having the fluorine layer 15. The second surface 22 is sequentially provided with: a bonding layer 12', a copper seed layer 13', and a copper plating layer 14' below the polyimide substrate 11 having a fluorine layer 15' as a fluorine-containing substrate.

[0040] The following describes the polyimide substrates 1 and 11, which have fluorine layers 5, 15, and 15' as fluorine-containing substrates constituting copper-clad laminates 10 and 20, bonding layers 2, 12, and 12', copper seed layers 3, 13, and 13', and copper plating layers 4, 14, and 14'.

[0041] <Polyimide substrates 1 and 11 are provided with fluorine layers 5, 15, and 15' as fluorine-containing substrates>

[0042] According to an embodiment of the present invention, the fluorinated substrate of the copper-clad laminate 10 can be a polyimide substrate 1 or 11 having fluorinated layers 5, 15, and 15'.

[0043] Polyimide substrates 1 and 11 can be modified polyimide (m-PI) substrates. The modified polyimide substrate is a resin substrate with reduced highly polar substituents. When a wireless signal flows through the circuit, the electric field around the circuit changes. When these electric field changes approach the relaxation time of the polarization within the resin substrate, the electric displacement is delayed. At this time, molecular friction occurs within the resin substrate, generating heat that affects the dielectric properties. Therefore, a modified polyimide substrate with reduced highly polar substituents is used as the substrate.

[0044] Fluorine layers 5, 15, and 15' may be disposed on one or both sides of the polyimide substrates 1 and 11. Fluorine layers 5, 15, and 15' may comprise at least one fluoropolymer selected from polytetrafluoroethylene (PTFE), perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), trifluorochloroethylene (CTFE), tetrafluoroethylene / trifluorochloroethylene (TFE / CTFE), ethylene trifluorochloroethylene (ECTFE), and polyvinylidene fluoride (PVDF). For example, fluorine layers 5, 15, and 15' may be perfluoroalkoxy (PFA).

[0045] The thickness of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can range from 25 μm to 100 μm. For example, the thickness of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be 25 μm to 90 μm, 25 μm to 80 μm, 25 μm to 70 μm, 25 μm to 60 μm, or 25 μm to 50 μm. Based on 100% of the thickness of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15', the thickness of the fluorinated layers 5, 15, and 15' can be 50% or less. If the thickness of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' is less than 25 μm, the productivity in preparing the copper-clad laminates 10 and 20 will decrease, and if it exceeds 100 μm, thin-film formation may not be possible.

[0046] The water contact angle of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be 120° or less. For example, the water contact angle of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be from 107° to 120°.

[0047] The diiodomethane contact angle for polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be 90° or less. For example, the diiodomethane contact angle for polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be from 77° to 90°.

[0048] The surface energy of polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' can be from 11 dyne / cm to 25 dyne / cm.

[0049] When the water contact angle, diiodomethane contact angle, and surface energy of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' are within the specified ranges, curling can be suppressed by ensuring proper coatability so that the thickness deviation of the fluorinated layers 5, 15, and 15' disposed on both sides of the polyimide substrates 1 and 11 is kept within ±10% or less. As a result, stable copper seed layers 3, 13, and 13' and copper plating layers 4, 14, and 14' can be formed on the surface of the polyimide substrates 1 and 11.

[0050] The fluorine content on the surface of polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' can be from 60 atomic% to 75 atomic%. Within this fluorine content range, polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' can have low dielectric constant, low dielectric loss, and low transmission loss. Polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' can have a dielectric constant (Dk) of 2.8 or less and a dielectric loss (Df) of 0.003 or less at a frequency of 20 GHz. For example, polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' can have a dielectric constant (Dk) of 0.01 to 2.8 and a dielectric loss (Df) of 0.00001 to 0.003 at a frequency of 20 GHz.

[0051] The coefficient of thermal expansion (CTE) of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be 25 ppm / °C or less. For example, the CTE of the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' can be from 0.01 ppm / °C to 25 ppm / °C or less. When the polyimide substrates 1 and 11 with fluorinated layers 5, 15, and 15' having such a CTE are used to prepare copper-clad laminates 10 and 20 together with copper foil including copper seed layers 3, 13, and 13' and copper plating layers 4, 14, and 14', the CTE of the copper layer composed of copper seed layers 3, 13, and 13' and copper plating layers 4, 14, and 14' (16 ppm to 20 ppm) is not much different from the CTE of the substrate, so that curling will not occur due to low residual stress, nor will warping or curling problems caused by shrinkage occur.

[0052] If necessary, before setting the bonding layers 2, 12, 12' (described later), the polyimide substrates 1, 11 with fluorinated layers 5, 15, 15' can be surface-treated by irradiating them with an ion beam that ionizes the reactive gas. As a result, by generating functional groups such as -OH, -CHO, -COOH on the surface of the fluorinated layers 5, 15, 15', copper-clad laminates 10, 20 with excellent adhesion to the copper seed layers 3, 13, 13' and copper plating layers 4, 14, 14' (described later) at room temperature and high temperature can be provided.

[0053] Surface treatment using ion beams can utilize reaction gases including at least one selected from nitrogen (N2), oxygen (O2), argon (Ar), xenon (Xe), and helium (He). For example, the reaction gas can consist of only oxygen (O2), or it can be a mixture of argon-oxygen (Ar-O2) or argon-nitrogen (Ar-N2). In this case, the adhesion between the polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' and the copper seed layers 3, 13, and 13' and the copper plating layers 4, 14, and 14' described later can be greatly improved at room temperature and high temperature.

[0054] Additionally, when mixed argon (Ar) is used as the reactant gas, the amount of argon can be from 0.1 vol% to 50 vol% based on the total volume of the reactant gas, or it can be from 0.1 vol% to 30 vol% or even from 0.1 vol% to 25 vol%. If argon (Ar) is mixed within the stated volume range, the adhesion between the polyimide substrates 1 and 11 with fluorine layers 5, 15, 15' and the copper seed layers 3, 13, 13' and copper plating layers 4, 14, 14' described later can be significantly improved at room temperature and high temperature.

[0055] The injection rate of the reactive gas can be, for example, 1 sccm to 100 sccm (Standard Cubic Centimeter per Minute), 50 sccm to 100 sccm, or 60 sccm to 80 sccm. Within this range, it has the effect of stably irradiating the surface of the polyimide substrates 1 and 11 provided with fluorine layers 5, 15, and 15'.

[0056] There is no limit to the irradiation dose of the ion beam; for example, it can be 1 × 10 ions / cm. 2 Up to 1×10 17 ions / cm 2 Within this range, the effect of ion beam irradiation on the surface of the polyimide layer can be maximized.

[0057] In addition, there is no limit to the irradiation time of the ion beam, which can be adjusted appropriately according to the purpose.

[0058] Ion beam irradiation can be performed using a roll-to-roll process. For example, in this roll-to-roll process, an ion beam can be applied along the machine direction (MD) to the surface of polyimide substrates 1 and 11, which are provided with fluorinated layers 5, 15, and 15', at a continuous supply of 2 to 10 mpm (meters per minute) for 1 to 50 seconds. Within this range, the room-temperature and high-temperature adhesion between the copper-clad laminates 10 and 20 of the polyimide substrates 1 and 11 and the copper seed layers 3, 13, and 13' and the copper plating layers 4, 14, and 14' (described later) is excellent, and excellent efficiency can be achieved.

[0059] The power of the applied ion beam can be from 0.1 kW to 5 kW, from 0.1 kW to 3 kW, or from 0.5 kW to 2 kW. Within this range, the adhesion between the polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15' and the copper seed layers 3, 13, and 13' and the copper plating layers 4, 14, and 14' (described later) can be greatly improved at both room temperature and high temperature.

[0060] <Combination layer 2, 12, 12'>

[0061] Bonding layers 2, 12, and 12' are disposed on polyimide substrates 1 and 11, which are provided with fluorine layers 5, 15, and 15'. Bonding layers 2, 12, and 12' may include one or more metals selected from Groups 4, 6, 13, and 14 of the periodic table. Bonding layers 2, 12, and 12' may include one or more metals selected from Groups 4, 6, 13, and 14 of the periodic table, or alloys containing such metals.

[0062] The bonding layers 2, 12, and 12' can be metal layers comprising a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or alloy layers containing such a metal. The bonding between the metal element with the aforementioned metal-oxygen (MO) bond dissociation energy and oxygen is relatively stable. As a result, adhesion is improved by ensuring stable metal oxides or alloy oxides at the interface between bonding layers 2, 12, and 12' and fluorine layers 5, 15, and 15', and transport losses can be minimized by applying bonding layers 2, 12, and 12', which have high conductivity.

[0063] The bonding layers 2, 12, 12' may comprise one or more metals selected from W, Ti, Sn, Cr, Al, and Mo, or alloys containing such metals. Because the metals or metal alloys are more stable in bonding with oxygen and can have lower transport losses than pure Ni metal bonding layers with strong magnetic properties, the conductivity of the surfaces of bonding layers 2, 12, 12' can be improved.

[0064] The bonding layers 2, 12, 12' may also include Ni, the content of which may be 50% by weight or less. The bonding layers 2, 12, 12' may be alloyed with Ni using metals selected from W, Ti, Sn, Cr, Al, and Mo, the Ni content in which may be 50% by weight or less. If the Ni content exceeds 50% by weight, high transport losses may occur, and the room temperature and high temperature adhesion between the polyimide substrates 1, 11 with fluorine layers 5, 15, 15' and the copper seed layers 3, 13, 13' and copper plating layers 4, 14, 14' (described later) may be reduced.

[0065] The thickness of bonding layers 2, 12, and 12' can range from 10 nm to 100 mm. For example, the thickness of bonding layers 2, 12, and 12' can range from 12 nm to 50 mm, or from 12 nm to 40 mm. If the thickness of bonding layers 2, 12, and 12' is less than 10 nm, sufficient metal oxide or alloy oxide cannot be formed at the interface with the substrate due to the thinness, which may make it difficult to ensure room temperature adhesion and high temperature adhesion. If the thickness of bonding layers 2, 12, and 12' is greater than 100 nm, bonding layers 2, 12, and 12' cannot be well etched during the etching process used to form the circuit and will remain, resulting in circuit defects and reduced room temperature adhesion.

[0066] <Copper seed layer 3, 13, 13' and copper plating layer 4, 14, 14'>

[0067] A copper seed layer is disposed on bonding layers 2, 12, and 12'. The copper seed layer can be a sputtered layer. The copper sputtered seed layer can have low transmission loss while maintaining the surface roughness of the polyimide substrates 1 and 11 with fluorine layers 5, 15, and 15'. As a sputtering method, physical vapor deposition (PVD), chemical vapor deposition (CVD), low-pressure chemical vapor deposition (LPCVD), and vacuum deposition methods can be used, but are not limited to these; all sputtering methods that can be used as corresponding sputtering methods can be used. For example, physical vapor deposition (PVD) can be used as a sputtering method.

[0068] The thicknesses of copper seed layers 3, 13, and 13' can be... to For example, the thickness of copper seed layers 3, 13, and 13' can be... to to to to or to When the thicknesses of the copper seed layers 3, 13, and 13' are within the specified range, conductivity can be ensured during film formation, and copper-clad laminates 10 and 20 with low surface roughness (Rz) and low transmission loss can be provided.

[0069] Copper plating layers 4, 14, and 14' are located on copper seed layers 3, 13, and 13'. Electroless plating or electrolytic plating methods can be used to form copper plating layers 4, 14, and 14'. For example, electrolytic plating can be used for copper plating layers 4, 14, and 14'.

[0070] As a method for forming the copper electrolytic plating layer, all methods available in the art can be used. For example, a copper electrolytic plating layer can be formed on one side of the copper seed layers 3, 13, 13' by electrolytic plating using an electrolytic plating solution comprising copper sulfate and sulfuric acid as base materials. Furthermore, for the sake of productivity and surface uniformity, additives such as brighteners, leveling agents, corrective agents, or modifiers can be added to the electrolytic plating solution.

[0071] The thickness of the copper plating layers 4, 14, and 14' can be 12 μm or less. For example, the thickness of the copper plating layers 4, 14, and 14' can be 0.1 μm to 12.0 μm, 1.0 μm to 12.0 μm, 2.0 μm to 12.0 μm, 4.0 μm to 12.0 μm, or 6.0 μm to 12.0 μm.

[0072] <Copper-clad laminate 10, 20>

[0073] According to an embodiment of the present invention, copper-clad laminates 10 and 20 include: polyimide substrates 1 and 11 having fluorine layers 5, 15, and 15' as fluorine-containing substrates; and bonding layers 2, 12, and 12', which are metal layers or alloy layers containing a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more on the polyimide substrates 1 and 11 having the fluorine layers 5, 15, and 15'. The thickness of bonding layers 2, 12, and 12' can be from 10 nm to 100 nm. The copper-clad laminates 10 and 20 can have improved dielectric properties at high frequencies, excellent coatability on the substrate surface, and excellent room-temperature and high-temperature adhesion between the substrate and the copper foil.

[0074] According to an embodiment of the present invention, the peel strength of the copper seed layer and the copper plating layer relative to the polyimide substrate with the fluorine layer, measured after being placed at room temperature (25°C) for 3 days, can be 0.65 kgf / cm or higher.

[0075] According to an embodiment of the present invention, the peel strength of the copper seed layer and copper plating layer relative to the polyimide substrate with the fluorine layer, measured after heat treatment at 150°C or higher twice or more and standing for 1 day, can be 0.35 kgf / cm or higher. For example, the copper seed layer and copper plating layer of the copper-clad laminate 10 and 20 are subjected to a first heat treatment at 150°C for 2 hours, then placed at room temperature for 30 minutes, subjected to a second heat treatment at 150°C for 2 hours, and subjected to a third heat treatment at 240°C for 10 minutes, and then placed at room temperature (25°C) for 1 day, can be 0.35 kgf / cm or higher.

[0076] <Electronic Components>

[0077] The electronic device according to another embodiment may include copper-clad laminates 10, 20.

[0078] The electronic device may include an antenna device or an antenna cable. For example, the antenna device may be an antenna device for a mobile phone or display. Additionally, the electronic device may include circuit boards such as web servers, Internet of Things (IoT) appliances for 5G, radar, and USB.

[0079] The construction and effects of the present invention will now be described in more detail through embodiments and comparative examples. However, it is clear that these embodiments are used to illustrate the present invention in more detail, and the scope of the present invention is not limited to these embodiments.

[0080] [Example]

[0081] Example 1: Copper-clad laminate

[0082] The following preparation method is used: Figure 2 The copper-clad laminate 20 shown.

[0083] Two polyimide films 11 with fluorine coatings 15 and 15' on both sides, each approximately 12.5 μm thick, were prepared (prepared by PI Advanced Materials, total thickness: 50 μm, dielectric constant at 20 GHz (D)). k ): 2.8, dielectric loss (D f (0.003, CTE: ≤25ppm / ℃) was used as the substrate. Ion beam treatment was performed on the first side 21 of the polyimide film 11 with a fluorine coating 15 using an ion beam source in a roll-to-roll sputtering apparatus. During the ion beam treatment, at 10... -6Under Torr pressure conditions, inert gas Ar was injected at 30 sccm and the process was carried out under an applied power of 1.0 kV. Then, a bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 using molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) with a purity of 99.995% by physical vapor deposition (PVD). Next, a copper seed layer 13 with a thickness of approximately 100 nm was formed on the bonding layer 12 using copper with a purity of 99.995% by physical vapor deposition (PVD). Then, the ion-beam-treated bonding layer 12' and the copper seed layer 13' were formed on the second side 22 of the polyimide film 11 with the fluorine coating 15' using the same method as described above. Subsequently, a copper plating layer with a thickness of approximately 12 μm was formed on each copper seed layer 13, 13' by electrolytic copper plating. The electrolytic copper plating solution used was Cu. 2+ A solution with a concentration of 28 g / L and sulfuric acid of 195 g / L, also containing 0.01 g / L of 3-N,N-dimethylaminodithiocarbamoyl-1-propanesulfonic acid as a brightener and corrective agent (commercially available from Atotech). Electrolytic copper plating at 34°C and 1.0 A / dm³. 2 Starting at a current density of 2.86 A / dm², the current density was gradually increased to 2.86 A / dm². 2 .

[0084] Example 2: Copper-clad laminate

[0085] A bonding layer 12 with a thickness of approximately 12 nm was formed on the ion-beam treated fluorine coating 15 using physical vapor deposition (PVD) with molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) of 99.995% purity. In addition, a copper-clad laminate was prepared using the same method as in Example 1.

[0086] Example 3: Copper-clad laminate

[0087] A bonding layer 12 with a thickness of approximately 25 nm was formed on the ion-beam treated fluorine coating 15 using physical vapor deposition (PVD) with molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) of 99.995% purity. In addition, a copper-clad laminate was prepared using the same method as in Example 1.

[0088] Example 4: Copper-clad laminate

[0089] A bonding layer 12 with a thickness of approximately 40 nm was formed on the ion-beam treated fluorine coating 15 using physical vapor deposition (PVD) with molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) of 99.995% purity. In addition, a copper-clad laminate was prepared using the same method as in Example 1.

[0090] Example 5: Copper-clad laminate

[0091] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 by physical vapor deposition using molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) and nickel (Ni, Ni-O bond dissociation energy: 360 kJ / mol) in a weight ratio of 70:30 (purity: 99.9% or higher). In addition, a copper-clad laminate 20 was prepared by the same method as in Example 1.

[0092] Example 6: Copper-clad laminate

[0093] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 using tungsten (W, W-O bond dissociation energy: 710 kJ / mol) and titanium (Ti, Ti-O bond dissociation energy: 670 kJ / mol) in a weight ratio of 90:10 (purity: 99.9% or higher) by physical vapor deposition (PVD). In addition, a copper-clad laminate 20 was prepared by the same method as in Example 1.

[0094] Example 7: Copper-clad laminate

[0095] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 using a 50:50 weight ratio of molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) and titanium (Ti, Ti-O bond dissociation energy: 670 kJ / mol) with a purity of 99.9% or higher by physical vapor deposition (PVD). In addition, a copper-clad laminate 20 was prepared by the same method as in Example 1.

[0096] Example 8: Copper-clad laminate

[0097] When the first surface 21 of a polyimide film 11 with a fluorine coating 15 is subjected to ion beam treatment using a roll-to-roll sputtering apparatus, during the ion beam treatment, at 10 -6 Under the pressure of Torr, the reaction gases Ar and O2 were injected at a flow ratio of 30:9 (sccm) and the process was carried out under the applied power of 1.0 kV. Otherwise, the copper-clad laminate 20 was prepared in the same manner as in Example 5.

[0098] Example 9: Copper-clad laminate

[0099] When the first surface 21 of a polyimide film 11 with a fluorine coating 15 is subjected to ion beam treatment using a roll-to-roll sputtering apparatus, during the ion beam treatment, at 10 -6 Under the pressure of Torr, the reactive gases Ar and N2 were injected at a flow ratio of 30:9 (sccm) and the process was carried out under the applied power of 1.0 kV. Otherwise, the copper-clad laminate 20 was prepared in the same manner as in Example 5.

[0100] Example 10: Copper-clad laminate

[0101] When the first surface 21 of a polyimide film 11 with a fluorine coating 15 is subjected to ion beam treatment using a roll-to-roll sputtering apparatus, during the ion beam treatment, at 10 -6 Under the pressure of Torr, the reactive gas O2 was injected at 9 sccm and the process was carried out under the applied power of 1.0 kV. Otherwise, the copper-clad laminate 20 was prepared in the same manner as in Example 3.

[0102] Example 11: Copper-clad laminate

[0103] When the first surface 21 of a polyimide film 11 with a fluorine coating 15 is subjected to ion beam treatment using a roll-to-roll sputtering apparatus, during the ion beam treatment, at 10 -6 Under the pressure of Torr, N2 reactive gas was injected at 9 sccm and the process was carried out under the applied power of 1.0 kV. Otherwise, the copper-clad laminate 20 was prepared in the same manner as in Example 3.

[0104] Comparative Example 1: Copper-clad laminate

[0105] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam treated fluorine coating 15 using 99.995% pure nickel (Ni, Ni-O bond dissociation energy: 360 kJ / mol) by physical vapor deposition (PVD). In addition, a copper-clad laminate 20 was prepared by the same method as in Example 1.

[0106] Comparative Example 2: Copper-clad laminate

[0107] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 using a weight ratio of nickel (Ni, Ni-O bond dissociation energy: 360 kJ / mol) and chromium (Cr, Cr-O bond dissociation energy: 480 kJ / mol) in a weight ratio of 80:20. In addition, a copper-clad laminate 20 was prepared using the same method as in Example 1.

[0108] Comparative Example 3: Copper-clad laminate

[0109] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 using a weight ratio of nickel (Ni, Ni-O bond dissociation energy: 360 kJ / mol) and copper (Cu, Cu-O bond dissociation energy: 280 kJ / mol) in a weight ratio of 65:35. In addition, a copper-clad laminate 20 was prepared using the same method as in Example 1.

[0110] Comparative Example 4: Copper-clad laminate

[0111] A bonding layer 12 with a thickness of approximately 20 nm was formed on the ion-beam-treated fluorine coating 15 by physical vapor deposition using molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) and nickel (Ni, Ni-O bond dissociation energy: 360 kJ / mol) in a weight ratio of 30:70. In addition, a copper-clad laminate 20 was prepared by the same method as in Example 1.

[0112] Comparative Example 5: Copper-clad laminate

[0113] A bonding layer 12 with a thickness of approximately 8 nm was formed on the ion-beam treated fluorine coating 15 using physical vapor deposition (PVD) with molybdenum (Mo, Mo-O bond dissociation energy: 400 kJ / mol) of 99.995% purity. In addition, a copper-clad laminate was prepared using the same method as in Example 1.

[0114] Comparative Example 6: Copper-clad laminate

[0115] The first surface 21 and the second surface 22 of the polyimide film 11 with the fluorine coating 15 were not subjected to ion beam treatment. Otherwise, a copper-clad laminate was prepared in the same manner as in Example 3.

[0116] Evaluation Example 1: Physical Property Evaluation

[0117] The physical properties of the copper-clad laminates prepared in Examples 1 to 11 and Comparative Examples 1 to 6 were evaluated using the following measurement methods. The results are shown in Table 1 below.

[0118] (1) Water contact angle (deg.), diiodomethane contact angle (deg.), and surface energy (dyne / cm) of the substrate surface

[0119] Under an atmosphere of 25°C and 50% RH, deionized water and diiodomethane were dropped 10 times each onto the surface of the fluorine-coated polyimide film substrate of the copper-clad laminate prepared in Examples 5, 8 to 11, and Comparative Example 6. The average values ​​of the water contact angle and the diiodomethane contact angle were then calculated using a contact goniometer (Drop Master 300, Kyowa). The surface energy was then calculated by substituting the contact angle values ​​into the Owens-Wendt-Rabel-Kaelble method.

[0120] (2) Fluorine content on substrate surface - X-ray photoelectron spectroscopy analysis

[0121] In the copper-clad laminates prepared in Examples 5, 10, 11, and Comparative Example 6, X-ray photoelectron spectroscopy (XPS) analysis was performed on the surfaces of fluorine-coated polyimide films that had undergone ion beam treatment or untreated fluorine-coated polyimide films. X-ray photoelectron spectroscopy analysis was performed using a K-Alpha X-ray Photoelectron Spectrometer (XPS) System manufactured by Thermo Fisher Scientific.

[0122] (3) Room temperature adhesion (kgf / cm)

[0123] Samples were prepared by cutting the copper-clad laminates prepared in Examples 1 to 7 and Comparative Examples 1 to 5 to predetermined sizes. After forming a circuit pattern with a width of 3 mm on the surface of the sample, the surface opposite to the surface where the circuit pattern was formed was fully etched. The samples were then left at room temperature (25°C) for 3 days, and peeled off using a peel strength tester (Shimazu AG-50NIS) at a tensile speed of 50 mm / min and an angle of 180°. The peel strength of the copper seed layer and the copper plating layer relative to the polyimide film with a fluorine coating was measured.

[0124] (4) High-temperature adhesion strength (kgf / cm)

[0125] Samples were prepared by cutting the copper-clad laminates prepared in Examples 1 to 7 and Comparative Examples 1 to 5 to predetermined sizes. After forming a circuit pattern with a width of 3 mm on the surface of the sample, the surface opposite to the surface where the circuit pattern was formed was fully etched. Then, the sample was subjected to a first heat treatment at 150°C for 2 hours, and then placed at room temperature for 30 minutes. Then, the sample was subjected to a second heat treatment at 150°C for 2 hours, and then a third heat treatment at 240°C for 10 minutes. Finally, after the sample was placed at room temperature (25°C) for 1 day, the peel strength of the copper seed layer and copper plating layer relative to the fluorine-coated polyimide film was measured using a peel strength tester (prepared by Shimazu, AG-50NIS) at a tensile speed of 50 mm / min and an angle of 180°.

[0126] Table 1

[0127]

[0128] As shown in Table 1, the water contact angle and diiodomethane contact angle of the substrate surfaces of the copper-clad laminates prepared in Examples 5, 8 to 11 were 107.3° to 110.8° and 77.7° to 84.5°, respectively, which were lower than those of the substrate surface of the copper-clad laminate prepared in Comparative Example 6. The surface energy of the substrate surfaces of the copper-clad laminates prepared in Examples 5, 8 to 11 was 14.4 dyne / cm to 18.8 dyne / cm, which was higher than that of the substrate surface of the copper-clad laminate prepared in Comparative Example 6. The fluorine content of the substrate surfaces of the copper-clad laminates prepared in Examples 1 to 7 was 64.92 atomic% to 73.82 atomic%.

[0129] It can be confirmed that by ensuring appropriate coatability on the substrate surface of the copper-clad laminate prepared in Examples 5, 8 to 11, a stable bonding layer, a copper seed layer and a copper plating layer are formed on the substrate.

[0130] The room temperature adhesion of the copper-clad laminates prepared in Examples 1 to 7 is 0.68 kgf / cm or higher, which is higher than that of the copper-clad laminates prepared in Comparative Examples 1 to 5. The high temperature adhesion of the copper-clad laminates prepared in Examples 1, 5 to 7 is 0.35 kgf / cm or higher, which is higher than that of the copper-clad laminate prepared in Comparative Example 5.

[0131] The copper-clad laminates prepared in Examples 1 to 7 comprise a bonding layer consisting of a metal layer containing a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or an alloy layer containing such metal, and are copper-clad laminates with a bonding layer thickness greater than or equal to 10 nm and less than or equal to 50 nm. Therefore, it can be confirmed that the bonding layer reacts with the functional groups on the surface of the polyimide-based film with a fluorine coating, thereby improving room-temperature adhesion. Furthermore, it can be confirmed that, for the same reason, the copper-clad laminates prepared in Examples 1, 5 to 7 also exhibit improved high-temperature adhesion. Thus, the copper-clad laminates prepared in Examples 1 to 7 can be applied internally and / or externally to miniaturized 5G mobile communication devices and other electronic devices.

[0132] According to one aspect of the present invention, a copper-clad laminate includes a fluorine-containing substrate; a bonding layer disposed on the fluorine-containing substrate; and a copper layer disposed on the bonding layer. The bonding layer is a metal layer comprising a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or an alloy layer containing such metal, and the thickness of the bonding layer can be from 10 nm to 100 nm. The copper-clad laminate can exhibit improved dielectric properties at high frequencies, excellent coatability on the substrate surface, and excellent room-temperature and high-temperature adhesion between the substrate and the copper foil.

[0133] Symbol Explanation

[0134] 1, 11: Polyimide (film) substrate; 2, 12, 12': Adhesive layer

[0135] 3, 13, 13': Copper seed layer

[0136] 4, 14, 14': Copper plating; 5, 15, 15': Fluorine coating.

[0137] 10, 20: Copper-clad laminate; 21: First side; 22: Second side

Claims

1. A copper-clad laminate, comprising: Fluorine-containing substrate; A bonding layer disposed on the fluorine-containing substrate; and A copper layer disposed on the bonding layer The bonding layer is a metal layer comprising a metal with a metal-oxygen (MO) bond dissociation energy of 400 kJ / mol or more, or an alloy layer containing such metal. The thickness of the bonding layer is 10 nm to 100 nm.

2. The copper-clad laminate according to claim 1, wherein, The water contact angle for the fluorinated substrate is 120° or less.

3. The copper-clad laminate according to claim 1, wherein, The diiodomethane contact angle with respect to the fluorinated substrate is 90° or less.

4. The copper-clad laminate according to claim 1, wherein, The surface energy of the fluorinated substrate is from 11 dyne / cm to 25 dyne / cm.

5. The copper-clad laminate according to claim 1, wherein, The fluorine content on the surface of the fluorine-containing substrate is 60 atomic% to 75 atomic%.

6. The copper-clad laminate according to claim 1, wherein, The bonding layer comprises one or more metals selected from W, Ti, Sn, Cr, Al and Mo, or alloys containing such metals.

7. The copper-clad laminate according to claim 1, wherein, The bonding layer also includes Ni, wherein the Ni content is 50% by weight or less.

8. The copper-clad laminate according to claim 1, wherein, The peel strength of the copper seed layer and copper plating layer relative to the polyimide substrate with the fluorine layer, measured after being placed at 25°C for 3 days, was 0.65 kgf / cm or higher.

9. The copper-clad laminate according to claim 1, wherein, The peel strength of the copper seed layer and copper plating relative to the polyimide substrate with the fluorine layer, measured after heat treatment at 150°C or higher at least twice and left to stand for 1 day, is 0.35 kgf / cm or higher.

10. The copper-clad laminate according to claim 1, wherein, The thickness of the copper plating layer is 12 μm or less.

11. An electronic device comprising a copper-clad laminate according to any one of claims 1 to 10.

12. The electronic device according to claim 11, wherein, The electronic devices include antenna devices or antenna cables.

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