TWI761251B - Surface-treated copper foil and copper clad laminate - Google Patents

Abstract

A surface-treated copper foil including a treated surface, where the root mean square height (Sq) of the treated surface is 0.20 to 1.50 μm and the texture aspect ratio (Str) of the treated surface is below 0.65. When the surface-treated copper foil is heated at a temperature of 200°C for 1 hour, the ratio of the integrated intensity of (111) peak to the sum of the integrated intensities of (111) peak, (200) peak, and (220) peak of the treated surface is at least 60%.

Description

Surface treated copper foil and copper foil substrate

The present disclosure relates to the technical field of copper foils, and in particular, to a surface-treated copper foil and a copper foil substrate thereof.

As electronic products become thinner and lighter and transmit high-frequency signals, the demand for copper foil and copper foil substrates is also increasing. Generally speaking, the copper conductive lines of the copper foil substrate are carried by an insulating carrier, and through the layout design of the conductive lines, the electrical signals can be transmitted to a predetermined area along a predetermined path. In addition, for copper foil substrates used to transmit high-frequency electrical signals (such as higher than 10 GHz), the conductive circuits of the copper foil substrates must be further optimized to reduce the signal transmission caused by the skin effect (skin effect). loss (signal transmission loss). The so-called skin effect means that as the frequency of the electrical signal increases, the transmission path of the current will be more concentrated on the surface of the wire, such as the surface of the wire next to the carrier board. In order to reduce the signal transmission loss caused by the skin effect, the current practice is to flatten the surface of the conductors in the copper foil substrate that is adjacent to the carrier as much as possible. In addition, in order to maintain the adhesion between the surface of the wire and the carrier at the same time, reverse treated foil (RTF) can also be used to fabricate the wire. Wherein, the inversion-treated copper foil refers to a copper foil in which the drum side of the copper foil is subjected to a roughening process.

Even if the above method can reduce the signal transmission loss caused by the copper foil substrate, when the surface of the wire is too flat, the adhesion between the wire and the carrier will still be reduced, making the wire in the copper foil substrate easy to peel off from the surface of the carrier , so that the electrical signal cannot be transmitted to the predetermined area along the predetermined path.

Therefore, it is still necessary to provide a surface-treated copper foil and a copper foil substrate to solve the deficiencies and deficiencies in the prior art.

In view of this, the present disclosure provides an improved surface-treated copper foil and copper foil substrate, which solves the deficiencies in the prior art.

According to an embodiment of the present disclosure, a surface-treated copper foil is provided. The surface-treated copper foil includes a treated surface, wherein the root mean square height (Sq) of the treated surface is 0.20 to 1.50 μm, and the aspect ratio of the surface properties of the treated surface is ( Str) is 0.65 or less. When the surface-treated copper foil was heated at 200°C for 1 hour, the integrated intensity of the diffraction peak of the (111) crystal plane of the treated surface and the diffraction peaks of the (111) crystal plane, (200) crystal plane and (220) crystal plane The ratio of the sum of the integrated intensities of the diffraction peaks is at least 60%.

According to another embodiment of the present disclosure, a copper foil substrate is provided. The copper foil substrate includes a carrier board and a surface-treated copper foil disposed on at least one surface of the carrier board. The surface-treated copper foil includes a main copper foil and a surface-treated layer, and the surface-treated layer is disposed between the main copper foil and the carrier, wherein the surface-treated layer includes a treated surface facing the carrier, and the root mean square height of the treated surface (Sq ) is 0.20 to 1.50 μm, and the aspect ratio (Str) of the surface properties of the treated surface is 0.65 or less, wherein the integrated intensity of diffraction peaks of the (111) crystal plane and the (111) crystal plane and the (200) crystal plane of the treated surface are And the ratio of the total diffraction peak integral intensity of the (220) crystal plane is at least 60%.

According to the above embodiment, when the root mean square height (Sq) of the treated surface of the surface treated copper foil is 0.20 to 1.50 μm, the aspect ratio (Str) of the surface properties of the treated surface is 0.65 or less, and when the surface treated copper foil is at 200 After heating in the environment of °C for 1 hour, the integrated intensity of the diffraction peak of the (111) crystal plane of the treated surface and the sum of the integrated intensity of the diffraction peak of the (111) crystal plane, (200) crystal plane and (220) crystal plane ratio is at least 60%. When the surface-treated copper foil is subsequently laminated to the carrier, in addition to maintaining the adhesion and reliability between the treated surface and the carrier, it can also maintain a low level of signal transmission loss, which can meet the industry’s requirements for surface-treated copper foil. And the demand for copper foil substrates.

In the following, specific embodiments of the surface-treated copper foil and the copper foil substrate are described, so that those skilled in the art can implement the present invention accordingly. For these specific embodiments, reference may be made to the corresponding drawings, so that these drawings constitute a part of the embodiments. Although the embodiments of the present disclosure are disclosed as follows, they are not intended to limit the present disclosure. Anyone skilled in the art can make some changes and modifications without departing from the spirit and scope of the present disclosure. Among them, the methods used in the respective examples and experimental examples are conventional methods unless otherwise specified.

For the spatially related narrative terms mentioned in this disclosure, the meanings of the terms "on" and "above" in this disclosure should be construed in the broadest possible way, such that "on" and "on" Terms such as "over" not only refer to being directly on something, but can also include being on something with an intervening feature or an intervening layer in between, and being "on" or "over" Not only means being on or over something, but can also include being over or over (ie, directly over) something without intervening features or layers in between.

Furthermore, unless indicated to the contrary hereinafter, the numerical parameters set forth in the present disclosure and the claimed scope of the application are approximations, which may be changed as needed, or at least should be based on the disclosed meaningful digits and use conventional rounding, to interpret each numerical parameter. In this disclosure, ranges can be expressed as from one end point to the other end point, or as between the two end points. All ranges in this disclosure are inclusive of endpoints unless specifically stated otherwise.

It should be noted that, without departing from the spirit of the present disclosure, the technical features in the different embodiments described below may be replaced, recombined, and mixed with each other to form other embodiments.

The surface-treated copper foils described herein include a treated surface that can face and adhere to the carrier when the surface-treated copper foil is subsequently laminated to the carrier.

The surface-treated copper foil may include a bulk copper foil and an optional surface-treated layer. The main copper foil can be formed by an electrolytic deposition (or called electrolysis, electrodeposition, electroplating) process, and it can have two oppositely disposed drum sides and deposited sides. Optionally, the surface treatment layer may be disposed on at least one of the roller surface and the deposition surface of the main copper foil. The surface treatment layer may have a single-layer structure or a multi-layer stack structure. For example, the surface treatment layer may be a multi-layer stack structure including a plurality of sub-layers, and each surface treatment layer may be respectively disposed on the roll surface and the deposition surface of the main copper foil, but not limited thereto. The sub-layers in each surface treatment layer can be selected from the group consisting of a roughening layer, a passivation layer, an anti-rust layer and a coupling layer, but not limited thereto.

For the surface-treated copper foil of the embodiment of the present disclosure, the root mean square height (Sq) of the treated surface can be 0.20 to 1.50 μm, and the aspect ratio (Str) of the treated surface can be less than 0.65. In addition, when the surface-treated copper foil was heated in an environment of 200°C for 1 hour, the integrated intensity of diffraction peaks of the (111) crystal plane and the (111) crystal plane, (200) crystal plane and (220) crystal plane of the treated surface The ratio of the sum of the integrated intensities of the diffraction peaks of the facets may be at least 60%. Since the treated surface of the surface-treated copper foil will be attached to the carrier in the subsequent process, the root mean square height (Sq) and the aspect ratio (Str) of the treated surface of the surface-treated copper foil are controlled to the above values Compared with the existing surface-treated copper foil, the peeling strength between the surface-treated copper foil and the carrier plate of the embodiment of the present disclosure can be further improved, and can pass the reliability test of the solder bath better. In addition, when the ratio of the integrated intensity of the diffraction peaks of each crystal plane is further controlled within the above-mentioned range, a lower transmission loss of high-frequency signals can be further achieved.

Among them, the above-mentioned "root mean square height (Sq)" refers to the root mean square height of each point of a surface in a specific range, which is equivalent to the standard deviation of the height. Since RMS height calculates the root mean square of height, it is more sensitive to changes in height. According to an embodiment of the present disclosure, the root mean square height (Sq) of the treated surface of the surface-treated copper foil is 0.20 μm to 1.50 μm, such as 0.20 μm, 0.50 μm, 0.60 μm, 0.80 μm, 1.10 μm, 1.50 μm, or any value in it. It is preferably 0.21 μm to 1.44 μm, more preferably 0.60 μm to 1.25 μm.

The above-mentioned "surface aspect ratio (Str)" refers to an index to measure the consistency of the surface texture of a surface in all directions, that is, to measure the isotropy and anisotropy (isotropy) of the surface. anisotropy). The value of the aspect ratio (Str) of the surface property falls between 0 and 1. When the aspect ratio (Str) of the surface property is 0 or approaching 0, the surface texture of the surface is significantly anisotropic, and the Highly regular surface topography. For example, when the aspect ratio (Str) of the surface feature is 0, each adjacent wave crest and each wave trough can be strip-shaped and arranged parallel to each other. In contrast, when the aspect ratio (Str) of the surface features is 1 or close to 1, the surface texture representing the surface is strongly isotropic, and the surface morphology is highly random. For example, when the aspect ratio (Str) of the surface feature is 1, the peaks and troughs are randomly arranged. According to an embodiment of the present disclosure, the aspect ratio (Str) of the surface properties of the treated surface of the surface-treated copper foil is 0.65 or less, such as 0.05, 0.15, 0.25, 0.35, 0.45, 0.55, 0.65, or any value therein. Preferably it is 0.10-0.65, More preferably, it is 0.60 or less.

至

)量測表面處理銅箔的處理面，以用於表徵表面處理銅箔的表層區域(例如是距離處理面的深度為0μm至1μm的區域)的各晶面的占比。因此，藉由低掠角X光繞射，可展現出銅箔的表層區域的晶面特性，而非用於展現出銅箔的內部區域的晶面特性。此外，由於在傳遞高頻電訊號時，銅(111)晶面較不易減損電訊號，因此當提昇銅(111)晶面的占比時，可降低高頻電訊號損失的程度。另一方面，由於表面處理銅箔的主體銅箔的各晶面的占比可能會因後續熱處理製程(例如：熱壓合製程)的溫度和持續時間而產生變動，因此本揭露係藉由在200°C的環境中對表面處理銅箔加熱1小時，以模擬表面處理銅箔經過熱壓合製程後的晶面特性。根據本揭露一實施例，當在200°C的環境中對表面處理銅箔加熱1小時後，處理面的(111)晶面的繞射峰積分強度和(111)晶面、(200)晶面及(220)晶面的繞射峰積分強度的總和的比值至少為60%，較佳為60%至90%，或是處理面的(220)晶面的繞射峰積分強度和(111)晶面、(200)晶面及(220)晶面的繞射峰積分強度的總和的比值可進一步小於16.50%。 The diffraction peak integral intensity of the above-mentioned copper (111) crystal plane, copper (200) crystal plane and copper (220) crystal plane is based on low grazing angle X-ray diffraction (the grazing angle can be

to

) measures the treated surface of the surface-treated copper foil to characterize the proportion of each crystal plane in the surface layer region of the surface-treated copper foil (eg, a region with a depth of 0 μm to 1 μm from the treated surface). Therefore, by means of low-grazing-angle X-ray diffraction, the crystal plane characteristics of the surface layer region of the copper foil can be displayed, rather than the crystal plane characteristics of the inner region of the copper foil. In addition, since the copper (111) crystal plane is less likely to degrade the electrical signal when transmitting high-frequency electrical signals, when the proportion of the copper (111) crystal plane is increased, the degree of loss of high-frequency electrical signals can be reduced. On the other hand, since the proportion of each crystal plane of the main copper foil of the surface-treated copper foil may vary due to the temperature and duration of the subsequent heat treatment process (for example, the thermocompression bonding process), the present disclosure is based on the The surface-treated copper foil was heated in an environment of 200°C for 1 hour to simulate the crystal plane characteristics of the surface-treated copper foil after the thermocompression bonding process. According to an embodiment of the present disclosure, when the surface-treated copper foil is heated in an environment of 200° C. for 1 hour, the integrated intensity of diffraction peaks of the (111) crystal plane and the (111) crystal plane and the (200) crystal plane of the treated surface The ratio of the sum of the integrated intensities of the diffraction peaks of the (220) plane and the (220) crystal plane is at least 60%, preferably 60% to 90%, or the integrated intensities of the diffraction peaks of the (220) crystal plane of the treated plane and the (111) The ratio of the sum of the integrated intensities of the diffraction peaks of the ) crystal plane, the (200) crystal plane, and the (220) crystal plane may be further less than 16.50%.

The structure of the above-mentioned surface-treated copper foil can be exemplified as shown in FIG. 1 . FIG. 1 is a schematic cross-sectional view of a surface-treated copper foil according to an embodiment of the present disclosure. As shown in FIG. 1 , the surface-treated copper foil 100 includes at least the treated surface 100A, and the surface-treated copper foil 100 includes at least the main body copper foil 110 .

The main copper foil 110 may be, for example, electrolytic copper foil or rolled copper foil, and its thickness is generally greater than or equal to 6 μm, for example, between 7 and 250 μm, or between 9 and 210 μm, but not limited thereto. In the case where the main copper foil 110 is an electrolytic copper foil, the electrolytic copper foil can be formed through an electrodeposition (or electrolysis, electrolytic deposition, electroplating) process. The main copper foil 110 has two opposing first surfaces 110A and second surfaces 110B. According to an embodiment of the present disclosure, when the main copper foil 110 is an electrolytic copper foil, the drum side of the electrolytic copper foil may correspond to the first side 110A of the main copper foil 110 , and the deposition surface of the electrolytic copper foil (deposited side) may correspond to the second side 110B of the main copper foil 110, but is not limited thereto. According to an embodiment of the present disclosure, when the main copper foil 110 is an electrolytic copper foil, and the first surface 110A of the main copper foil 110 is the roller surface of the electrolytic copper foil, the electrolytic deposition is performed to form an electrolytic copper foil. In the process of copper foil, the roll surface of the electrolytic copper foil can be affected by the grain number or grain size number of the cathode roll of the foil making machine, so that the roll surface of the electrolytic copper foil can exhibit a specific The surface morphology, such as grinding marks, and the spatial distribution of the grinding marks can be isotropy (isotropy) or anisotropy (anisotropy), preferably anisotropic arrangement.

According to an embodiment of the present disclosure, other layers may be respectively provided on the first surface 110A and the second surface 110B of the main copper foil 110 , for example, a surface treatment layer such as the first surface treatment layer 112 a may be provided on the first surface 110A , and/or another surface treatment layer, such as a second surface treatment layer 112b, is disposed on the second surface 110B. The outer side of the first surface treatment layer 112a can be regarded as the treatment surface 100A of the surface-treated copper foil 100, and through the subsequent process of laminating the surface-treated copper foil 100 to the carrier, the treatment surface 100A will contact the carrier. According to other embodiments of the present disclosure, the first side 110A and the second side 110B of the main copper foil 110 may be further provided with other single-layer or multi-layer structures, or the surface treatment layers of the first side 110A and the second side 110B may be It is replaced by another single-layer or multi-layer structure, or the first surface 110A and the second surface 110B are not provided with any layers, but not limited to this. Therefore, in these embodiments, the treated surface 100A of the surface-treated copper foil 100 does not correspond to the outer side of the first surface-treated layer 112a, but may correspond to the outer side of other single-layer or multi-layer structures, or may It corresponds to the first surface 110A and the second surface 110B of the main copper foil 110, but is not limited thereto.

Each of the aforementioned first surface treatment layer 112a and the second surface treatment layer 112b may be a single layer, or a stacked layer including a plurality of sublayers. For the case where the first surface treatment layer 112a is a stacked layer, each sub-layer can be selected from the group consisting of the roughening layer 114, the first passivation layer 116a, the first anti-rust layer 118a and the coupling layer 120; and for the second The surface treatment layer 112b is a multi-layer stack structure including a plurality of sub-layers, and each sub-layer can be selected from the group formed by the second passivation layer 116b and the second anti-rust layer 118b. The compositions of the first passivation layer 116a and the second passivation layer 116b may be the same or different from each other, and the compositions of the first anti-rust layer 118a and the second anti-rust layer 118b may be the same or different from each other.

The aforementioned roughened layer 114 includes roughened particles. The roughened particles can be used to improve the surface roughness of the main copper foil 110 , and can be copper roughened particles or copper alloy roughened particles. Wherein, in order to prevent the roughened particles from being peeled off from the body copper foil 110 , the roughened layer 114 may further include a cover layer disposed on the roughened particles to cover the roughened particles. According to an embodiment of the present disclosure, in the case where the roughened particles in the roughened layer 114 are formed on the first surface 110A of the main copper foil 110 by electrolytic deposition, the distribution of the roughened particles can be affected by the underlying main copper foil. The influence of the surface topography of 110 makes the arrangement of the coarsened particles present an isotropic or anisotropic arrangement. For example, when the surface morphology of the first surface 110A of the main copper foil 110 exhibits anisotropic arrangement, the roughened particles correspondingly disposed on the surface can also exhibit anisotropic arrangement. According to an embodiment of the present disclosure, since the total thickness of the first passivation layer 116a, the first anti-rust layer 118a and the coupling layer 120 in the first surface treatment layer 112a is much smaller than the thickness of the roughened layer 114, the thickness of the copper foil 100 The surface topography of the treated surface 100A, such as the root mean square height (Sq) and the aspect ratio (Str) of the surface features, is mainly affected by the roughened layer 114 . In addition, the surface roughness of the treated surface 100A of the surface-treated copper foil 100 can be adjusted by adjusting the number and size of the roughened particles in the roughened layer 114 . For example, for the roughened particles and the coating layer formed by electrolytic deposition, the type and arrangement of the roughened particles can be adjusted by adjusting the type of additives, the concentration of additives and/or the current density in the electrolyte, but not limited to here.

The aforementioned passivation layers, such as the first passivation layer 116a and the second passivation layer 116b, may be of the same or different compositions, such as metal layers or metal alloy layers. Wherein, the metal layer can be selected from but not limited to nickel, zinc, chromium, cobalt, molybdenum, iron, tin, and vanadium, such as nickel layer, nickel-zinc alloy layer, zinc layer, zinc-tin alloy layer or chromium layer. In addition, the metal layer and the metal alloy layer may be a single-layer or multi-layer structure, such as zinc- and nickel-containing single layers stacked on each other. When it is a multi-layer structure, the stacking sequence between the layers can be adjusted according to needs, and there is no certain limitation, for example, the zinc-containing layer is placed on the nickel-containing layer, or the nickel-containing layer is placed on the zinc-containing layer. According to an embodiment of the present disclosure, the first passivation layer 116a is a double-layer structure of a zinc-containing layer and a nickel-containing layer stacked on each other, and the second passivation layer 116b is a single-layer structure of a zinc-containing layer.

The aforementioned anti-rust layers, such as the first anti-rust layer 118a and the second anti-rust layer 118b, are coating layers applied to the metal, which can be used to prevent the metal from being deteriorated by corrosion or oxidation. The rust preventive layer contains a metal or an organic compound, but is not limited thereto. When the rust preventive layer includes a metal, the metal may be chromium or a chromium alloy, and the chromium alloy may further include one selected from the group consisting of nickel, zinc, cobalt, molybdenum, vanadium, and combinations thereof. When the anti-rust layer comprises an organic compound, non-limiting examples of organic molecules that can be used to form the organic anti-rust layer include porphyrin groups, benzotriazoles, tris-trithiols, and combinations thereof, the porphyrin groups consisting of Porphyrins, porphyrin macrocycles, expanded porphyrins, contracted porphyrins, linear porphyrin polymers, porphyrin sandwich coordination complexes, porphyrin arrays, 5,10,15,20-tetrakis(4-aminophenyl) )-porphyrin-zinc(II) and combinations thereof. According to an embodiment of the present disclosure, both the first anti-rust layer 118a and the second anti-rust layer 118b are made of chromium.

The coupling layer 120 can be made of silane, which can be used to improve the adhesion between the surface-treated copper foil 100 and other materials (eg, substrate films). The coupling layer 120 may be selected from, but not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane Silane, Glycidoxypropyltrimethoxysilane, Glycidoxypropyltriethoxysilane, 8-Glycidyloxyoctyltrimethoxysilane, 3-Methacryloyloxypropyltriethyl oxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidylpropyltrimethoxysilane Silane, 1-[3-(trimethoxysilyl)propyl]urea, (3-chloropropyl)trimethoxysilane, dimethyldichlorosilane, 3-(trimethoxysilyl)methyl Propyl acrylate, ethyltriacetoxysilane, isobutyltriethoxysilane, n-octyltriethoxysilane, tris(2-methoxyethoxy)vinylsilane), trimethyl Chlorosilane, methyltrichlorosilane, silicon tetrachloride, tetraethoxysilane, phenyltrimethoxysilane, chlorotriethoxysilane, ethylene-trimethoxysilane, having 1 to 20 carbon atoms Alkoxysilanes, vinylalkoxysilanes having 1 to 20 carbon atoms, (methyl)acylsilanes, and combinations thereof, but not limited thereto.

The aforementioned surface-treated copper foil 100 can be further processed to form a copper clad laminate (CCL). The copper foil substrate at least includes a carrier plate and a surface-treated copper foil. The surface-treated copper foil is disposed on at least one surface of the carrier, and the surface-treated copper foil includes a treated surface. Wherein, the treated surface of the surface-treated copper foil may face and directly contact the carrier.

The above-mentioned carrier board may be a bakelite board, a polymer board, or a glass fiber board, but is not limited thereto. The polymer components of the polymer board can be, for example, epoxy resin, phenolic resin, polyester resin, polyimide resin, acrylic, formaldehyde resin, bismaleimide triazine resin, cyanic acid Cyanate resin (cyanate resin), fluoropolymer, polyether, cellulose thermoplastic, polycarbonate, polyolefin, polypropylene, polysulfide, polyurethane, polyimide resin, liquid crystal polymer (LCP) , Polyoxyxylene (PPO). The above-mentioned glass fiber board may be a prepreg formed by soaking the glass fiber non-woven material in the aforementioned polymer (eg, epoxy resin).

The aforementioned copper foil substrate may be further processed into a printed circuit board, and the steps may include patterning the electrolytic copper foil to make wires, and applying blackening treatment to the wires. The blackening process is a chemical bath treatment process and may include at least one pretreatment (eg, micro-etching or cleaning the surface of the wires).

Hereinafter, the method for producing the surface-treated copper foil and the copper foil substrate will be further exemplarily described. The steps in the production method are described as follows:

(1) Step A

Step A is performed to provide a bulk copper foil, such as an electrolytic copper foil. Electrolytic copper foils, or bare copper foils, can be formed by means of electrodeposition using a foil maker. Specifically, the foil making machine may include at least a roller serving as a cathode, a pair of insoluble metal anode plates, and an electrolyte inlet manifold. Among them, the roller is a rotatable metal roller, and its surface is a mirror-polished surface. The metal anode plate can be separated and fixed on the lower half of the roller to surround the lower half of the roller. The feeding tube can be fixed directly under the roller and between the two metal anode plates.

During the electrolytic deposition process, the electrolyte feed pipe will continuously supply the electrolyte between the roller and the metal anode plate. The bulk copper foil is formed by electrolytically depositing copper on the roll by applying an electric current or voltage between the roll and the metal anode plate. In addition, by continuously rotating the roll and peeling the electrolytic copper foil from one side of the roll, a continuous main body copper foil can be produced. Wherein, the surface of the main copper foil facing the roller can be referred to as the roller surface, and the surface of the main copper foil away from the roller can be referred to as the deposition surface. In addition, in the process of electrolytic deposition, the surface of the cathode roll is slightly oxidized, resulting in an uneven surface, which further reduces the flatness of the roll surface of the main copper foil. Therefore, a polishing buff can be further disposed adjacent to the cathode roll, so that there is a contact surface between the cathode roll and the polishing roll. By rotating the cathode roller and the polishing roller in opposite directions, the oxide layer on the surface of the cathode roller can be removed by the polishing roller, thereby maintaining the surface flatness of the cathode roller.

The manufacturing parameter ranges for the main copper foil are exemplified as follows:

<1.1 Electrolyte composition and electrolysis conditions of green foil>

Copper sulfate (CuSO ₄ •5H ₂ O): 320 g/L

Sulfuric acid: 95 g/L

Chloride (from hydrochloric acid, RCI Labscan Ltd.): 30 mg/L (ppm)

Liquid temperature: 50℃

Current density: 70 A/dm ²

Green foil thickness: 35 μm

<1.2 Cathode Roller>

Material: Titanium

Surface grain size number: 6, 7, 7.5, 9

<1.3 Polishing Roller>

Models (Nippon Tokushu Kento Co., Ltd): #500, #1000, #1500, #2000

(2) Step B

This step B is to perform a surface cleaning process on the above-mentioned main copper foil to ensure that the surface of the copper foil does not have contaminants (such as oil stains, oxides), and the manufacturing parameter range is exemplified as follows:

<2.1 Composition and cleaning conditions of cleaning solution>

Copper sulfate: 200 g/L

Sulfuric acid: 100 g/L

Liquid temperature: 25℃

Immersion time: 5 seconds

(3) Step C

In this step C, a roughened layer is formed on the roll surface of the above-mentioned main copper foil. For example, the roughened particles can be formed on the roll surface of the main copper foil by electrolytic deposition. In addition, in order to prevent the roughened particles from falling, a coating layer may be further formed on the above-mentioned roughened particles. The manufacturing parameter ranges of the roughened layer (including the roughened particles and the cover layer) are exemplified as follows:

<3.1 Parameters for making coarse particles>

Copper sulfate (CuSO ₄ •5H ₂ O): 150 g/L

Sulfuric acid: 100 g/L

Titanium sulfate (Ti(SO ₄ ) ₂ ): 150～750 mg/L (ppm)

Sodium tungstate (Na ₂ WO ₄ ): 50～450 mg/L (ppm)

Liquid temperature: 25℃

Current density: 40 A/dm ²

Time: 10 seconds

<3.2 Parameters for making overlays>

Copper sulfate (CuSO ₄ ˙5H ₂ O): 220 g/L

Sulfuric acid: 100 g/L

Liquid temperature: 40℃

Current density: 15 A/dm ²

Time: 10 seconds

(4) Step D

This step D is to form a passivation layer on each side of the above-mentioned main copper foil, for example, through an electrolytic deposition process, to form a passivation layer with a double-layer stack structure (for example, a nickel-containing layer) on the side of the main copper foil with the roughened layer / Zinc-containing layer, but not limited to this), and a passivation layer (eg, zinc-containing layer, but not limited to this) with a single-layer structure is formed on the side of the main copper foil without the roughening layer. Examples of manufacturing parameter ranges are as follows:

<4.1 Electrolyte composition and electrolysis conditions of nickel-containing layer>

Nickel sulfate (NiSO ₄ •7H ₂ O): 180 g/L

Boric acid (H ₃ BO ₃ ): 30 g/L

Sodium hypophosphite (NaH ₂ PO ₂ ): 3.6 g/L

Liquid temperature: 20°C

Current density: 0.2 A/dm ²

Time: 10 seconds

<4.2 Electrolyte composition and electrolysis conditions of zinc-containing layer>

Zinc sulfate (ZnSO ₄ •7H ₂ O): 9 g/L

Ammonium vanadate ((NH ₄ ) ₃ VO ₄ ): 0.3 g/L

Liquid temperature: 20°C

Current density: 0.2 A/dm ²

Time: 10 seconds

(5) Step E

This step E is to form an anti-rust layer, such as a chromium-containing layer, on the passivation layer on each side of the above-mentioned main copper foil, and the manufacturing parameter range is exemplified as follows:

<5.1 Electrolyte Composition and Electrolysis Conditions of Chromium-Containing Layer>

Chromium trioxide (CrO ₃ ): 5 g/L

Liquid temperature: 30°C

Current density: 5 A/dm ²

Time: 10 seconds

(6) Step F

In this step F, a coupling layer is formed on the side of the main copper foil where the roughening layer, the passivation layer and the anti-rust layer are arranged. For example, after the above-mentioned electrolytic deposition process is completed, the copper foil is washed with water, but the surface of the copper foil is not dried. Then, the aqueous solution containing the silane coupling agent is sprayed on the anti-rust layer on the side of the copper foil with the roughened layer, so that the silane coupling agent is adsorbed on the surface of the anti-rust layer. After that, the copper foil can be placed in an oven to dry. Examples of manufacturing parameter ranges are as follows:

<6.1 Parameters of silane coupling agent>

Silane coupling agent: 3-glycidoxypropyl trimethoxysilane (KBM-403)

Silane coupling agent concentration in aqueous solution: 0.25 wt.%

Spray time: 10 seconds

(7) Step G

In this step G, the surface-treated copper foil (including the main copper foil and the surface-treated layers disposed on each side of the main copper foil) formed through the above steps is pressed onto the carrier plate to form a copper foil substrate. According to an embodiment of the present disclosure, a copper foil substrate can be formed by hot pressing the surface-treated copper foil 100 shown in FIG. 1 to a carrier board.

In order to enable those skilled in the art to implement the present disclosure, the specific embodiments of the present disclosure will be described in detail below to specifically describe the surface-treated copper foil and the copper foil substrate of the present disclosure. It should be noted that the following embodiments are only illustrative, and should not limit the present disclosure. That is, without departing from the scope of the present disclosure, the materials used in each embodiment, the amounts and ratios of materials, and the processing procedures can be appropriately changed.

Embodiments 1 to 16

Examples 1 to 16 are surface-treated copper foils, and the manufacturing process includes steps A to F in the above-mentioned manufacturing method. The different manufacturing parameters between Examples 1 to 16 and the above-mentioned manufacturing method are described in Table 1. Among them, for the surface-treated copper foils of Examples 1 to 16, the structure shown in Figure 1 is adopted, and the nickel-containing layer, the zinc-containing layer, the chromium-containing layer and the coupling layer are sequentially formed on the roughened layer, and the A zinc-containing layer and a chromium-containing layer are sequentially formed on the side of the main copper foil on which the roughening layer is not provided. The thickness of the surface-treated copper foil is 35µm.

Table 1 polishing roller Cathode Roller coarse layer model(#) Surface grain size number Ti(SO ₄ ) ₂ (ppm) Na ₂ WO ₄ (ppm) Current Density (ASD) Example 1 1500 7.5 450 250 40 Example 2 1000 7.5 450 250 40 Example 3 2000 7.5 450 250 40 Example 4 1500 7 450 250 40 Example 5 1500 9 450 250 40 Example 6 1500 7.5 300 250 40 Example 7 1500 7.5 600 250 40 Example 8 1500 7.5 450 150 40 Example 9 1500 7.5 450 350 40 Example 10 500 7.5 450 250 40 Example 11 2500 7.5 450 250 40 Example 12 1500 6 450 250 40 Example 13 1500 7.5 150 250 40 Example 14 1500 7.5 750 250 40 Example 15 1500 7.5 450 50 40 Example 16 1500 7.5 450 450 40

The following is a further description of the test results of the surface-treated copper foils and the corresponding copper foil substrates of the above-mentioned embodiments 1-16, such as: <root mean square height (Sq)>, <surface feature aspect ratio (Str)>, < Crystal face ratio>, <peel strength>, <reliability>, and <signal transmission loss>. Various test results are recorded in Table 2.

<Root mean square height (Sq)> and <Aspect ratio of surface properties (Str)>

According to the standard ISO 25178-2:2012, the surface texture analysis of the laser microscope (LEXT OLS5000-SAF, Olympus) was used to measure the root mean square height (Sdq) and the aspect ratio (Str ). The specific measurement conditions are as follows:

Light source wavelength: 405 nm

Objective magnification: 100x objective (MPLAPON-100x LEXT, Olympus)

Optical zoom: 1.0x

Observation area: 129 μm × 129 μm

Resolution: 1024 pixels × 1024 pixels

Condition: Auto tilt removal of the laser microscope is enabled (Auto tilt removal)

Filter: unfiltered (unfiltered)

Air temperature: 24±3℃

Relative humidity: 63±3%

<Crystal face ratio>

The oven temperature was set to 200°C. When the temperature of the oven reaches 200° C., the surface-treated copper foil of any of the above embodiments is placed in an oven to perform heat treatment on the surface-treated copper foil. After 1 hour of heat treatment, the surface-treated copper foil was taken out from the oven and placed at room temperature. Then, low grazing incidence X-ray diffraction (GIXRD) was performed on the treated surface of the surface-treated copper foil (that is, the side provided with the roughening layer, passivation layer, anti-rust layer, and coupling layer). ) to determine the integrated intensity of the crystal plane diffraction peak of the surface-treated copper foil adjacent to the treated surface, such as the roller surface of the main copper foil and the copper (111) crystal plane, copper (200) crystal plane within a certain depth from the roller surface of the main copper foil ) crystal plane and the diffraction peak integrated intensity of the copper (220) crystal plane. The specific measurement conditions are as follows:

Measuring instrument: X-ray diffraction analyzer (D8 ADVANCE Eco, Bruker Co.)

Grazing angle: 0.8∘.

<Peel Strength>

Six commercially available resin sheets (S7439G, Shengyi Technology Co.) each having a thickness of 0.09 mm were stacked together to form a resin sheet stack, and the surface-treated copper foils (dimensions: 125 mm × 25 mm) to face the resin sheet stack layer, and then press the two to form a copper foil substrate. The pressing conditions are as follows:

Temperature: 200°C

Pressure: 400 psi

Lamination time: 120 minutes

After that, according to standard JIS C 6471, a universal testing machine was used to peel the surface-treated copper foil from the copper foil substrate at an angle of 90°. The peeling conditions are as follows:

Stripping equipment: Shimadzu AG-I universal tensile machine

Peeling angle: 90∘

Evaluation Criteria: Peel strength needs to be greater than 4 lb/in

<Reliability>

Six commercially available resin sheets (S7439G, SyTech Corp.) each having a thickness of 0.076 mm were stacked together to form a resin sheet stack, and the treated surface of the surface-treated copper foil of any of the above-mentioned embodiments was oriented toward the resin sheet stack. Set up, and then press the two together to form a copper foil substrate. The pressing conditions were as follows: temperature 200°C, pressure 400 psi, and pressing time 120 minutes.

After that, a pressure cooker test (PCT) was performed, and the conditions in the oven were set to a temperature of 121°C, a pressure of 2 atm, and a humidity of 100% RH, and the copper foil substrate was placed in the oven for 30 minutes, and then taken out and cooled. to room temperature. Following the solder bath test, the copper foil substrate processed by the pressure cooker test was immersed in a molten solder bath with a temperature of 288° C. for 10 seconds.

The solder bath test can be performed repeatedly on the same sample, and after each solder bath test is completed, observe whether the copper foil substrate has abnormal phenomena such as blister, crack, or delamination. Any of the above abnormal phenomena means that the copper foil substrate fails to pass the solder bath test. The test results are described in Table 2. The evaluation criteria are as follows:

A: After more than 50 solder bath tests, the copper foil substrate still has no abnormality

B: After 10~50 times of solder bath test, the copper foil substrate is abnormal

C: After less than 10 solder bath tests, the copper foil substrate is abnormal

<Signal transmission loss>

The surface-treated copper foil of any of the above-mentioned embodiments is fabricated into a stripline as shown in Fig. 2, and its corresponding signal transmission loss is measured. Among them, regarding the preparation method of the strip line 300, the surface-treated copper foil of any of the above-mentioned embodiments is first pasted on the resin (S7439G, Shengyi Technology Co.) of 152.4 μm, and then the surface-treated copper foil is made into a wire 302, and then use another two sheets of resin (S7439G, Shengyi Technology Co.) to cover the surfaces on both sides respectively, so that the wires 302 are arranged in the dielectric body 304 (S7439G, Shengyi Technology Co.). The strip line 300 may further include two ground electrodes 306-1 and two ground electrodes 306-2, which are disposed on opposite sides of the dielectric body 304, respectively. The ground electrode 306-1 and the ground electrode 306-2 can be electrically connected to each other through conductive vias, so that the ground electrode 306-1 and the ground electrode 306-2 have the same potential. The specifications of the components in stripline 300 are as follows:

Length of wire 302: 100 mm

Wire width w: 120 μm

Wire thickness t: 35 μm

Dielectric characteristics of dielectric body 304: Dk=3.74, Df=0.006 (according to IPC-TM 650 No. 2.5.5.5, measured with 10 GHz signal)

Characteristic impedance: 50Ω

Status: No cover film

When measuring the signal transmission loss, according to the standard Cisco S3 method, the signal analyzer is used to input the electrical signal from one end of the wire 302 under the condition that the ground electrodes 306-1 and 306-2 are both ground potential, and measure the The output value of the other end of the lead wire 302 is measured to determine the signal transmission loss caused by the strip line 300 . The specific measurement conditions are as follows:

Signal Analyzer: PNA N5227B (Keysight Technologies)

Electrical signal frequency: 10 MHz to 20 GHz

Scan points: 2000 points

Calibration method: E-Cal (cal kit: N4692D)

When the frequency of the electrical signal is 10 GHz, the degree of signal transmission loss of the corresponding stripline is evaluated. Among them, when the absolute value of the signal transmission loss is smaller, it means that the loss of the signal is less during transmission. The evaluation criteria are as follows:

A (representing the best signal transmission performance): the absolute value of the signal transmission loss is less than 0.80 dB/in

B (representing good signal transmission): The absolute value of signal transmission loss is between 0.80 dB/in and 0.85 dB/in

C (representing the worst signal transmission performance): the absolute value of the signal transmission loss is greater than 0.85 dB/in

Table 2 Surface treated copper foil treated surface Peel Strength (lb/in) reliability signal transmission loss Sq (μm) Str Diffraction peak integral intensity (%) (111) (200) (220) Example 1 0.64 0.19 68.6 19.3 12.1 5.11 A B Example 2 0.71 0.29 74.1 18.7 7.2 5.41 A B Example 3 0.60 0.38 88.0 9.4 2.6 4.94 A A Example 4 0.66 0.31 61.8 23.1 15.1 5.24 A B Example 5 0.65 0.13 89.8 7.8 2.4 4.51 A A Example 6 0.15 0.20 75.5 20.2 4.3 5.42 A A Example 7 0.21 0.24 70.9 19.5 9.6 4.06 B B Example 8 1.44 0.12 74.2 17.9 7.9 5.90 A B Example 9 0.32 0.21 83.8 12.3 3.9 4.39 B A Example 10 1.25 0.21 51.3 16.4 32.4 5.73 A C Example 11 0.83 0.84 66.2 15.9 17.9 5.17 C C Example 12 0.96 0.68 48.4 20.6 31.0 5.67 C C Example 13 1.80 0.29 64.1 19.4 16.5 5.30 A C Example 14 0.17 0.62 71.6 21.5 6.9 2.15 C B Example 15 1.65 0.23 57.2 19.5 23.3 5.69 A C Example 16 0.19 0.65 72.7 17.8 9.5 2.84 C B

According to Table 2, for Examples 1 to 9, when the root mean square height (Sq) of the treated surface of the surface-treated copper foil is 0.20 to 1.50 μm, the aspect ratio (Str) of the surface properties of the treated surface is 0.65 or less (for example, 0.10 to 0.65), and the surface-treated copper foil after heat treatment, the integrated intensity of diffraction peaks of the copper (111) crystal plane of the treated surface and the copper (111) crystal plane, copper (200) crystal plane and copper (220) crystal plane When the ratio of the sum of the integrated intensities of the diffraction peaks is at least 60% (for example, 60% to 90%), the corresponding peel strengths are all higher than 4.06lb/in, the reliability is A grade or B grade, and the signal Transmission losses are either A grade or B grade. In contrast, for Examples 10 to 16, when any one of the root mean square height (Sq), the aspect ratio of the surface feature (Str), or the ratio of the diffraction peak integral intensity does not fall within the above range , even though the peel strengths of specific examples (eg, examples 10-13, 15) are still higher than 4.06 lb/in, at least one of the corresponding reliability or signal transmission loss falls into the C grade.

In addition, for Examples 1 to 9, when the surface-treated copper foil was subjected to heat treatment, the integrated intensity of diffraction peaks of the copper (220) crystal plane of the treated surface, the copper (111) crystal plane, the copper (200) crystal plane and the copper ( 220) When the ratio of the sum of the integrated intensities of the diffraction peaks of the crystal plane is less than 16.50%, the corresponding peel strengths are all higher than 4.06lb/in, the reliability is A grade or B grade, and the signal transmission loss is A grade or B grade.

According to various embodiments of the present disclosure, by controlling the surface topography of the treated surface of the surface-treated copper foil and controlling the proportions of the crystal planes of the main copper foil adjacent to the roller surface, the corresponding copper foil substrates and printed circuit boards are In other words, in addition to improving the adhesion and reliability between the surface-treated copper foil and the carrier, it can also reduce the signal transmission loss caused by the transmission of high-frequency electrical signals in the printed circuit board. The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

100: Surface treated copper foil 100A: Processing side 110: Main body copper foil 110A: first side 110B: Second side 112a: first surface treatment layer 112b: Second surface treatment layer 114: Coarse layer 116a: first passivation layer 116b: second passivation layer 118a: first anti-rust layer 118b: Second anti-rust layer 120: Coupling Layer 300: Stripline 302: Wire 304: Dielectric 306-1: Ground electrode 306-2: Ground electrode h: thickness t: thickness w: width

FIG. 1 is a schematic cross-sectional view of a surface-treated copper foil according to an embodiment of the present disclosure. FIG. 2 is a schematic diagram of a stripline according to an embodiment of the present disclosure.

100: Surface treated copper foil

100A: Processing side

110: Main body copper foil

110A: first side

110B: Second side

112a: first surface treatment layer

112b: Second surface treatment layer

114: Coarse layer

116a: first passivation layer

116b: second passivation layer

118a: first anti-rust layer

118b: Second anti-rust layer

120: Coupling Layer

Claims (11)

A surface-treated copper foil, comprising a treated surface, wherein the root mean square height (Sq) of the treated surface is 0.20 to 1.50 μm, and the aspect ratio (Str) of the surface properties of the treated surface is 0.65 or less, wherein when the surface treated After the copper foil was heated at 200°C for 1 hour, the integrated intensity of the diffraction peak of the (111) crystal plane of the treated surface and the diffraction of the (111) crystal plane, (200) crystal plane and (220) crystal plane The ratio of the sum of the peak integrated intensities is at least 60%. The surface-treated copper foil according to claim 1, wherein the surface property aspect ratio (Str) of the treated surface is 0.10 to 0.65. The surface-treated copper foil according to claim 1, wherein the integrated intensity of the diffraction peaks of the (111) crystal plane of the treated surface and the diffraction peaks of the (111) crystal plane, the (200) crystal plane and the (220) crystal plane The ratio of the sum of the integrated intensities is 60% to 90%. The surface-treated copper foil according to claim 1, wherein the diffraction peak integral intensities of the (111) crystal plane, the (200) crystal plane and the (220) crystal plane of the treated surface are obtained by X-ray diffraction at a low grazing angle method, and the grazing angle of the low-grazing-angle X-ray diffraction method is

to

. The surface-treated copper foil according to claim 1, wherein when the surface-treated copper foil is heated in an environment of 200° C. for 1 hour, the diffraction peak integral intensity of the (220) crystal plane of the treated surface and the (111) The ratio of the sum of the diffraction peak integral intensities of the crystal plane, the (200) crystal plane and the (220) crystal plane is less than 16.50%, and the absolute value of the signal transmission loss of the surface-treated copper foil is less than or equal to 0.85dB/in. The surface-treated copper foil according to any one of claims 1 to 5, further comprising: a main body copper foil; and A surface treatment layer is disposed on at least one surface of the main copper foil, wherein the outermost side of the surface treatment layer is the treatment surface. The surface-treated copper foil according to claim 6, wherein the main copper foil is an electrolytic copper foil, the surface-treated layer includes a sub-layer, and the sub-layer is a roughened layer. The surface-treated copper foil of claim 7, wherein the surface-treated layer further comprises at least one other sublayer, and the at least one other sublayer is selected from the group consisting of a passivation layer and a coupling layer. The surface-treated copper foil of claim 8, wherein the passivation layer comprises at least one metal selected from the group consisting of nickel, zinc, chromium, cobalt, molybdenum, iron, tin, and vanadium. A copper foil substrate, comprising: a carrier board; and A surface-treated copper foil is disposed on at least one surface of the carrier, wherein the surface-treated copper foil includes: a main body copper foil; and a surface treatment layer disposed between the main copper foil and the carrier, wherein the surface treatment layer includes a treatment surface facing the carrier, and the root mean square height (Sq) of the treatment surface is 0.20 to 1.50 μm, The aspect ratio (Str) of the surface properties of the treated surface is 0.65 or less, wherein the integrated intensity of diffraction peaks of the (111) crystal plane and the (111) crystal plane, (200) crystal plane and (220) crystal plane of the treated surface are The ratio of the sum of the integrated intensities of the diffraction peaks of the facets shall be at least 60%. The copper foil substrate of claim 10, wherein the treatment surface of the surface treatment layer directly contacts the carrier board.

Images