Patent Application
20250137155
This application claims the benefit of priority to Taiwan Patent Application No. 112141938, filed on Nov. 1, 2023. The entire content of the above identified application is incorporated herein by reference.
Some references, which may include patents, patent applications and various publications, may be cited and discussed in the description of this disclosure. The citation and/or discussion of such references is provided merely to clarify the description of the present disclosure and is not an admission that any such reference is “prior art” to the disclosure described herein. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference was individually incorporated by reference.
The present disclosure relates to a copper foil, and more particularly to a carrier-attached ultra-thin copper foil and a method for producing the same.
In the related art, a fine circuit wiring formed on a printed circuit board (PCB) is fabricated by using a carrier-attached ultra-thin copper foil. A conventional carrier-attached ultra-thin copper foil has a laminated structure composed of an ultra-thin copper foil, a release layer, and a copper foil carrier.
The conventional carrier-attached ultra-thin copper foil can be hot-pressed with a prepreg (e.g., a semi-cured bonding sheet), and a peeling force between the ultra-thin copper foil and the copper foil carrier is relevant to a thickness distribution and a content distribution of the release layer.
In the conventional carrier-attached ultra-thin copper foil, the release layer is formed of a single metal element or multi-element alloy metals, including metal elements such as Ni, Co, Mo, W, or their combinations. However, since the release layer deposited on the copper foil carrier through electroplating has uneven distribution of thickness and ingredient contents, the peeling strength between the ultra-thin copper foil and the copper foil carrier is difficult to control.
In response to the above-referenced technical inadequacies, the present disclosure provides a carrier-attached ultra-thin copper foil and a method for producing the same.
In one aspect, the present disclosure provides a method for producing a carrier-attached ultra-thin copper foil. The method includes: providing a copper foil carrier; and forming a release layer on a side surface of the copper foil carrier. The release layer contains a copper-containing organic compound, and a chemical structure of the copper-containing organic compound has at least a copper-nitrogen bond (Cu—N bond). The method further includes: forming an ultra-thin copper foil layer on a side surface of the release layer away from the copper foil carrier. The copper foil carrier is capable of being separated from the ultra-thin copper foil layer through the release layer.
In certain embodiments, the release layer has at least two infrared absorption peaks respectively at a first position between 1020 cm−1 and 1025 cm−1 and a second position between 1098 cm−1 and 1103 cm−1 as analyzed by Fourier transform infrared spectroscopy (FTIR).
In certain embodiments, the copper-containing organic compound in the release layer is an organic copper complex.
In certain embodiments, the release layer is formed on the side surface of the copper foil carrier by immersing the copper foil carrier in an electroplating solution and performing an electroplating process on the copper foil carrier. The electroplating solution contains: a nitrogen-containing heterocyclic compound, a copper-containing metal salt, and a buffering agent. In the electroplating solution, a concentration of the nitrogen-containing heterocyclic compound is between 0.05 g/L and 40 g/L, a concentration of the copper-containing metal salt is between 5 g/L and 100 g/L, and a concentration of the buffering agent is between 10 g/L and 600 g/L.
In certain embodiments, in the electroplating solution, a weight ratio among the nitrogen-containing heterocyclic compound, the copper-containing metal salt, and the buffering agent is 1:5 to 40:100 to 600.
In certain embodiments, the nitrogen-containing heterocyclic compound is a bicyclic nitrogen-containing heterocyclic compound. In certain embodiments, the copper-containing metal salt is selected from the group consisting of copper pyrophosphate, copper sulfate, copper carbonate, copper acetate, copper nitrate, copper oxide, cuprous cyanide, sodium copper cyanide, and potassium copper cyanide. In certain embodiments, the buffering agent is selected from the group consisting of potassium pyrophosphate, boric acid, sulfuric acid, ammonium sulfate, citric acid, ammonium citrate, sodium citrate, sodium acetate, sodium carbonate, potassium tartrate, and sodium gluconate.
In certain embodiments, the copper foil carrier is electroplated in the electroplating solution for a predetermined time ranging from 1 to 20 seconds. An electric current density of the electroplating process ranges from 0.1 ASD to 5 ASD, and a temperature of the electroplating solution ranges from 30° C. to 60° C.
In certain embodiments, the chemical structure of the copper-containing organic compound further has a carbon-hydrogen bond (C—H bond), a carbon-nitrogen bond (C—N bond), and a nitrogen-hydrogen bond (N—H bond).
In certain embodiments, a nitrogen content of the release layer analyzed by X-ray photoelectron spectroscopy (XPS) ranges from 0.1 wt % to 25 wt %.
In certain embodiments, elemental ratios of the release layer analyzed by X-ray photoelectron spectroscopy (XPS) are that: an N1s peak area to a total peak area is 15 to 25 atomic %, an O1s peak area to the total peak area is 25 to 35 atomic %, a C1s peak area to the total peak area is 30 to 40 atomic %, and a Cu2p peak area to the total peak area is 5 to 18 atomic %. A ratio of the Cu2p peak area relative to the N1s peak area ranges from 0.3 to 0.9.
In another aspect, the present disclosure provides a carrier-attached ultra-thin copper foil including a copper foil carrier, a release layer, and an ultra-thin copper foil layer. The release layer is formed on a side surface of the copper foil carrier. The release layer contains a copper-containing organic compound, and a chemical structure of the copper-containing organic compound has at least a copper-nitrogen bond (Cu—N bond).
The ultra-thin copper foil layer is formed on a side surface of the release layer away from the copper foil carrier. The copper foil carrier is capable of being separated from the ultra-thin copper foil layer through the release layer.
In certain embodiments, the release layer has at least two infrared absorption peaks respectively at a first position of between 1020 cm−1 and 1025 cm−1 and a second position of between 1098 cm−1 and 1103 cm−1 analyzed by Fourier transform infrared spectroscopy (FTIR).
In certain embodiments, the copper-containing organic compound in the release layer is an organic copper complex.
In certain embodiments, a thickness of the copper foil carrier is between 10 micrometers and 50 micrometers, a thickness of the release layer is between 20 nanometers and 300 nanometers, and a thickness of the ultra-thin copper foil layer is between 1 micrometer and 5 micrometers.
In certain embodiments, the release layer is formed on the side surface of the copper foil carrier by immersing the copper foil carrier in an electroplating solution and performing an electroplating process on the copper foil carrier. The electroplating solution contains: a nitrogen-containing heterocyclic compound, a copper-containing metal salt, and a buffering agent.
In certain embodiments, a surface roughness of a side surface of the ultra-thin copper foil layer away from the release layer is greater than a surface roughness of another side surface of the ultra-thin copper foil layer that is in contact with the release layer.
In certain embodiments, a peeling strength of the copper foil carrier peeled from the ultra-thin copper foil layer through the release layer is between 1 gf/cm and 20 gf/cm according to JIS Z 0237-2009.
In certain embodiments, the release layer further has absorption peaks including a carbon-hydrogen bond (C—H bond), a carbon-nitrogen bond (C—N bond), and a nitrogen-hydrogen bond (N—H bond) analyzed by Fourier transform infrared spectroscopy (FTIR).
In certain embodiments, a nitrogen content of the release layer analyzed by X-ray photoelectron spectroscopy (XPS) ranges from 0.1 wt % to 25 wt %. Elemental ratios of the release layer analyzed by X-ray photoelectron spectroscopy (XPS) are that: an N1s peak area to a total peak area is 15 to 25 atomic %, an O1s peak area to the total peak area is 25 to 35 atomic %, a CIs peak area to the total peak area is 30 to 40 atomic %, and a Cu2p peak area to the total peak area is 5 to 18 atomic %. In addition, a ratio of the Cu2p peak area relative to the N1s peak area ranges from 0.3 to 0.9.
In certain embodiments, the N1s peak area is 20.63 atomic %, the O1s peak area is 29.78 atomic %, the CIs peak area is 36.77 atomic %, and the Cu2p peak area is 12.82 atomic %. In addition, the ratio of the Cu2p peak area relative to the N1s peak area is 0.6214.
In certain embodiments, the release layer exhibits a curve chart of Cu2p peak analyzed by X-ray photoelectron spectroscopy (XPS) and focused ion beam (FIB).
Therefore, in the carrier-attached ultra-thin copper foil and the method for producing the same provided by the present disclosure, by virtue of “a copper foil carrier; a release layer formed on a side surface of the copper foil carrier, in which the release layer contains a copper-containing organic compound, and a chemical structure of the copper-containing organic compound has at least a Cu—N bond; and an ultra-thin copper foil layer formed on a side surface of the release layer away from the copper foil carrier,” the copper foil carrier and the ultra-thin copper foil layer can have good release effect there-between.
Furthermore, the difficulty in controlling the peeling strength, attributed to the non-uniform distribution of thickness and the inconsistent content spread in the release layer, can be effectively improved.
These and other aspects of the present disclosure will become apparent from the following description of the embodiment taken in conjunction with the following drawings and their captions, although variations and modifications therein may be affected without departing from the spirit and scope of the novel concepts of the disclosure.
The described embodiments may be better understood by reference to the following description and the accompanying drawings, in which:
The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Like numbers in the drawings indicate like components throughout the views. As used in the description herein and throughout the claims that follow, unless the context clearly dictates otherwise, the meaning of “a”, “an”, and “the” includes plural reference, and the meaning of “in” includes “in” and “on”. Titles or subtitles can be used herein for the convenience of a reader, which shall have no influence on the scope of the present disclosure.
The terms used herein generally have their ordinary meanings in the art. In the case of conflict, the present document, including any definitions given herein, will prevail. The same thing can be expressed in more than one way. Alternative language and synonyms can be used for any term(s) discussed herein, and no special significance is to be placed upon whether a term is elaborated or discussed herein. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms is illustrative only, and in no way limits the scope and meaning of the present disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given herein. Numbering terms such as “first”, “second” or “third” can be used to describe various components, signals or the like, which are for distinguishing one component/signal from another one only, and are not intended to, nor should be construed to impose any substantive limitations on the components, signals or the like.
Referring to
It is worth mentioning that a copper foil material formed by the method for producing the carrier-attached ultra-thin copper foil according to the embodiment of the present disclosure is suitable for use in production of a substrate of a printed circuit board, but the present disclosure is not limited thereto.
As shown in
In addition, in terms of thickness, a thickness of the copper foil carrier 1 can be, for example, between 10 micrometers and 50 micrometers, preferably between 15 micrometers and 40 micrometers, and more preferably between 18 micrometers and 35 micrometers.
In the present embodiment, step S110 further includes: washing the copper foil carrier 1 with water to remove impurities or chemical residues on a surface of the copper foil carrier 1, but the present disclosure is not limited thereto.
As shown in
In addition, a chemical structure of the copper-containing organic compound has at least a copper-nitrogen bond (Cu—N bond). It is worth mentioning that the copper-nitrogen bond (Cu—N bond) in the chemical structure of the copper-containing organic compound can be analyzed by Fourier-transform infrared spectroscopy (FTIR).
For example, as shown in
In one embodiment of the present disclosure, the copper-containing organic compound is an organic copper complex, but the present disclosure is not limited thereto.
In addition, in terms of thickness, a thickness of the release layer 2 can be, for example, between 20 nanometers and 300 nanometers, preferably between 35 nanometers and 200 nanometers, and more preferably between 50 nanometers and 100 nanometers.
Furthermore, the release layer 2 is formed by immersing the copper foil carrier 1 in an electroplating solution L (also called an electroplating liquid) and performing an electroplating process on the copper foil carrier 1, so as to form the release layer 2 on the side surface of the copper foil carrier 1 as shown in
That is, the release layer 2 is formed from the electroplating solution L during the electroplating process.
In the present embodiment, the electroplating solution L contains: a nitrogen-containing heterocyclic compound (1), a copper-containing metal salt (2), and a buffering agent (3).
The nitrogen-containing heterocyclic compound (1) is an organic compound, preferably a bicyclic nitrogen-containing heterocyclic compound, and more preferably benzotriazole, but the present disclosure is not limited thereto. For example, the bicyclic nitrogen-containing heterocyclic compound can be, for example, indoline or 1,4-diazabicyclo[2.2.2]octane.
The chemical formula of benzotriazole is C6H5N3, and its chemical structure is as follows:
Further, a concentration of the nitrogen-containing heterocyclic compound in the electroplating solution L is between 0.05 g/L and 40 g/L, preferably between 0.1 g/L and 20 g/L, and more preferably between 0.1 g/L and 10 g/L.
It is worth mentioning that the nitrogen-containing heterocyclic compound is a source of an organic substance of the copper-containing organic compound for forming the release layer 2.
Furthermore, the copper-containing metal salt (2) is an inorganic compound, which is a source of copper elements in the release layer 2 or a source of copper ions in the electroplating solution L. The copper-containing metal salt can react with the nitrogen-containing heterocyclic compound to form an organic copper complex, thereby forming the release layer 2 on the copper foil carrier 1.
In some embodiments of the present disclosure, the copper-containing metal salt is selected from the group consisting of copper pyrophosphate, copper sulfate, copper carbonate, copper acetate, copper nitrate, copper oxide, cuprous cyanide, sodium copper cyanide, and potassium copper cyanide.
In a preferred embodiment of the present disclosure, the copper-containing metal salt is copper pyrophosphate, the chemical formula of copper pyrophosphate is Cu2P2O7, and its chemical structure is as follows:
The following chemical structure represents the dissociation state of copper pyrophosphate in water.
Further, a concentration of the copper-containing metal salt (e.g., copper pyrophosphate) in the electroplating solution L is between 5 g/L and 100 g/L, preferably between 5 g/L and 50 g/L, and more preferably between 10 g/L and 30 g/L.
Furthermore, the addition of the buffering agent (3) enables the copper-containing metal salt to be evenly dispersed or dissolved in the plating solution L.
In addition, the buffering agent is capable of adjusting a pH value of the electroplating solution L, but the present disclosure is not limited thereto.
In some embodiments of the present disclosure, the buffering agent is selected from the group consisting of potassium pyrophosphate, boric acid, sulfuric acid, ammonium sulfate, citric acid, ammonium citrate, sodium citrate, sodium acetate, sodium carbonate, potassium tartrate, and sodium gluconate.
In a preferred embodiment of the present disclosure, the buffering agent is potassium pyrophosphate, the chemical formula of potassium pyrophosphate is K4P2O7, and its chemical structure is as follows:
The following chemical structure represents the dissociation state of potassium pyrophosphate in water.
Further, a concentration of the buffering agent (e.g., potassium pyrophosphate) in the electroplating solution L is between 10 g/L and 600 g/L, preferably between 100 g/L and 500 g/L, and more preferably between 200 g/L and 500 g/L.
In some embodiments of the present disclosure, in the electroplating solution L, a weight ratio among the organic compound (e.g, the nitrogen-containing heterocyclic compound), the copper-containing metal salt (e.g, copper pyrophosphate), and the buffering agent (e.g, potassium pyrophosphate) can be, for example 1:5 to 40:100 to 600, preferably 1:10 to 30:100 to 500, and more preferably 1:15 to 25:200 to 500, but the present disclosure is not limited thereto.
In the present embodiment, a liquid component of the electroplating solution L is water, which can be, for example, deionized (DI) water, reverse osmosis (RO) water, or ultrapure (MQ) water. In one embodiment of the present disclosure, the liquid component is deionized (DI) water, but the present disclosure is not limited thereto.
As shown in
Furthermore, the copper foil carrier 1 is electroplated in the electroplating solution L for a predetermined time to form the release layer 2 on the at least one side surface of the copper foil carrier 1.
In some embodiments of the present disclosure, the predetermined time ranges from 1 second to 20 seconds, preferably ranges from 1 second to 15 seconds, and more preferably ranges from 3 seconds to 15 seconds. For example, the predetermined time can be 3 seconds, 5 seconds, 7 seconds, 9 seconds, 11 seconds, 13 seconds, or 15 seconds.
In addition, an electroplating condition of the copper foil carrier 1 in the electroplating solution L is that a current density ranges from 0.1 ASD to 5 ASD (i.e. A/dm2, ampere per square decimeter), and preferably ranges from 0.2 ASD to 2 ASD. For example, the current density can be 0.2 ASD, 0.6 ASD, 1.0 ASD, 1.5 ASD, or 2 ASD.
Further, a liquid temperature of the electroplating solution L ranges from 30° C. to 60° C., preferably ranges from 40° C. to 60° C. For example, the liquid temperature of the electroplating solution L is 40° C., 45° C., 50° C., 55° C., or 60° C., but the present disclosure is not limited thereto.
It is worth mentioning that in the present embodiment, the copper foil carrier 1 is an individual sheet that is immersed in the electroplating solution L, but the present disclosure is not limited thereto.
Referring to
Furthermore, the predetermined time for electroplating the copper foil carrier 1 in the electroplating solution L can be adjusted by controlling the rolling speed of the multiple guide rollers R.
Furthermore, at least one pair of electrodes E are disposed inside the liquid storage tank T, so that the copper foil carrier 1 immersed in the electroplating solution L can undergo an electroplating process through the energization of the electrodes E, but the present disclosure is not limited thereto.
Step S120 further includes: taking out the copper foil carrier 1 formed with the release layer 2 from the electroplating solution L; and blowing and drying the copper foil carrier 1 to remove excess liquid components (e.g., moisture) from the release layer 2.
According to the above configuration, the release layer 2 can be formed by electroplating the copper foil carrier 1 via the electroplating solution L. That is, the release layer 2 is formed from the electroplating solution L.
As shown in
In one embodiment of the present disclosure, the ultra-thin copper foil layer 3 can be formed by depositing copper metal on the release layer 2 through a wet electrolysis process or a wet electroplating process, but the present disclosure is not limited thereto.
Further, a thickness of the ultra-thin copper foil layer 3 can be, for example, between 1 micrometer and 5 micrometers, preferably between 1.5 micrometers and 4 micrometers, and more preferably between 1.5 micrometers and 3 micrometers.
It is worth mentioning that, as shown in
According to the above configuration, a laminate composed of the copper foil carrier 1, the release layer 2, and the ultra-thin copper foil layer 3 is defined as the carrier-attached ultra-thin copper foil E (also referred to as a copper foil laminated structure) according to the embodiment of the present disclosure.
In some embodiments of the present disclosure, the copper foil carrier 1 is capable of being separated from the ultra-thin copper foil layer 3 through the release layer 2. A peeling strength of the copper foil carrier 1 peeled from (or separated from) the ultra-thin copper foil layer 3 through the release layer 2 can be, for example, between 1 gf/cm and 20 gf/cm, and preferably between 5 gf/cm and 10 gf/cm.
The peeling strength can be, for example, measured according to JIS Z 0237-2009, but the present disclosure is not limited thereto.
According to the above configuration, the copper foil carrier 1 can have good peeling strength with the ultra-thin copper foil layer 3 through the design of the release layer 2. Accordingly, the technical problem of difficulty in controlling the peeling strength caused by the uneven thickness of the release layer deposited on the copper foil carrier in the related art can be effectively improved.
It is worth mentioning that in the present embodiment, the laminate composed of the copper foil carrier 1, the release layer 2, and the ultra-thin copper foil layer 3 is firstly heat-treated at 180° C. to 220° C. for 70 minutes to 110 minutes, and then measured according to JIS Z 0237-2009 so as to obtain the peeling strength.
Furthermore,
In a specific embodiment of the present disclosure, as shown in Experimental Example 1 of
The carrier-attached ultra-thin copper foil E is hot pressed to a dielectric layer material PP (e.g., prepreg) at 200° C. for 90 minutes via the ultra-thin copper foil layer 3, so as to obtain a hard board. In the hard board, the peeling strength between the copper foil carrier 1 and the ultra-thin copper foil 3 is about 5 gf/cm.
The ratio between the concentration (g/L) of the organic compound and the concentration of copper pyrophosphate (i.e., copper ion source) in the remaining Experimental Examples is fixed. For example, the concentration of the organic compound in Experimental Example 2 is 0.95 g/L, and the concentration of copper pyrophosphate (copper ion source) is 19 g/L. That is, the ratio between the concentration of the organic compound and the concentration of copper pyrophosphate (i.e., copper ion source) is 1:20.
It can be seen from the experimental data in
It is worth mentioning that, according to the test results of the above-mentioned Experimental Example 1, the release layer 2 is composed of the copper-containing organic compound. The chemical structure of the copper-containing organic compound has at least a copper-nitrogen bond (Cu—N bond). In addition, as shown in
Furthermore, a nitrogen content of the release layer 2 analyzed by X-ray photoelectron spectroscopy (XPS) ranges from 0.1 wt % to 25 wt %, and preferably ranges from 1 wt % to 20 wt %. For example, the nitrogen content of the release layer 2 can be 5 wt %, 10 wt %, 15 wt %, or 20 wt %.
From another perspective, elemental ratios (atomic %) of the release layer 2 analyzed by X-ray photoelectron spectroscopy (XPS) are that an N1s peak area (associated with nitrogen elements) to a total peak area is 15 to 25 atomic %, an O1s peak area (associated with oxygen elements) to the total peak area is 25 to 35 atomic %, a C1s peak area (associated with carbon elements) to the total peak area is 30 to 40 atomic %, and a Cu2p peak area (associated with copper elements) to the total peak area is 5 to 18 atomic %. Furthermore, a ratio of the Cu2p peak area relative to the N1s peak area ranges from 0.3 to 0.9, and preferably ranges from 0.5 to 0.7, but the present disclosure is not limited thereto.
In a specific embodiment of the present disclosure, the elemental ratios (atomic %) of the release layer 2 analyzed by X-ray photoelectron spectroscopy (XPS) are that the N1s peak area is 20.63 atomic %, the O1s peak area is 29.78 atomic %, the CIs peak area is 36.77 atomic %, and the Cu2p peak area is 12.82 atomic %.
The table below shows test results of the elemental ratios (atomic %) analyzed by XPS analysis.
In addition, the ratio of the Cu2p peak area relative to the N1s peak area is 0.6214 (i.e., the ratio obtained by dividing 12.82 by 20.63).
In addition,
From the above qualitative analysis, it can be known that the nitrogen-containing organic compound (e.g., benzotriazole) exists in the organic copper complex of the release layer 2.
It should be noted that the nitrogen elements in the release layer 2 are derived from the nitrogen-containing heterocyclic compound in the electroplating solution L.
It is worth mentioning that X-ray photoelectron spectroscopy (XPS) is a quantitative spectroscopic technique that is used to determine an elemental composition, an empirical formula, and chemical states and electronic states of the elements within a material. This technique involves irradiating the material to be analyzed with X-rays while measuring the kinetic energy and the number of electrons that escape from an underside (within a range of from 1 nm to 10 nm) of a surface of the material, thereby obtaining an X-ray photoelectron spectrum.
The above is the descriptions of the method for producing the carrier-attached ultra-thin copper foil according to the embodiment of the present disclosure.
As shown in
In one embodiment of the present disclosure, the copper foil carrier 1 is an electrolytic copper foil. The copper foil carrier 1 has a thickness ranging from 10 micrometers to 50 micrometers, preferably ranging from 15 micrometers to 40 micrometers, and more preferably ranging from 18 micrometers to 35 micrometers, but the present disclosure is not limited thereto.
The release layer 2 contains a copper-containing organic compound (also referred to as a copper-based polymer). In one embodiment of the present disclosure, a content of the copper-containing organic compound in the release layer 2 is not less than 80 wt %. Preferably, the release layer 2 is composed of the copper-containing organic compound.
In addition, a chemical structure of the copper-containing organic compound has at least a copper-nitrogen bond (Cu—N bond).
It is worth mentioning that the copper-nitrogen bond (Cu—N bond) in the chemical structure of the copper-containing organic compound can be analyzed by Fourier-transform infrared spectroscopy (FTIR).
For example, as shown in
In one embodiment of the present disclosure, the copper-containing organic compound is an organic copper complex, but the present disclosure is not limited thereto.
In addition, a thickness of the release layer 2 can be, for example, between 20 nanometers and 300 nanometers, preferably between 35 nanometers and 200 nanometers, and more preferably between 50 nanometers and 100 nanometers.
The release layer 2 can be formed by immersing the copper foil carrier 1 in an electroplating solution L and performing an electroplating process on the copper foil carrier 1. Accordingly, the release layer 2 is formed on the side surface of the copper foil carrier 1.
The electroplating solution L contains: a nitrogen-containing heterocyclic compound (1), a copper-containing metal salt (2), and a buffering agent (3). The copper-containing metal salt can be, for example, copper pyrophosphate, and the buffering agent can be, for example, potassium pyrophosphate.
The material characteristics of each component in the electroplating solution L have been described above, and will not be reiterated herein.
It is worth mentioning that the nitrogen-containing heterocyclic compound is the source of the organic component of the copper-containing organic compound in the release layer 2. In addition, the copper-containing metal salt (e.g., copper pyrophosphate) is the source of the copper elements in the release layer 2. Furthermore, the ultra-thin copper foil layer 3 can be formed by depositing a copper metal on the release layer 2 through a wet electrolysis process or wet electroplating process.
Further, a thickness of the ultra-thin copper foil layer 3 can be, for example, between 1 micrometer and 5 micrometers, preferably between 1.5 micrometers and 4 micrometers, and more preferably between 1.5 micrometers and 3 micrometers.
In the present embodiment of the present disclosure, a side surface of the ultra-thin copper foil layer 3 away from the release layer 2 is an uneven and rough surface, but the present disclosure is not limited thereto.
The copper foil carrier 1 is capable of being separated from the ultra-thin copper foil layer 3 through the release layer 2.
A peeling strength of the copper foil carrier 1 peeled from (or separated from) the ultra-thin copper foil layer 3 through the release layer 2 can be, for example, between 1 gf/cm and 20 gf/cm, and preferably between 5 gf/cm and 10 gf/cm.
The peeling strength can be, for example, measured according to JIS Z 0237-2009, but the present disclosure is not limited thereto.
According to the above configuration, the copper foil carrier 1 can have good peeling strength with the ultra-thin copper foil layer 3 through the design of the release layer 2.
Referring to
As shown in
As shown in
As shown in
The above is the method for producing the substrate of the printed circuit board according to an embodiment of the present disclosure. However, the application of the carrier-attached ultra-thin copper foil E is not limited to that described in the above method.
In conclusion, in the carrier-attached ultra-thin copper foil and the method for producing the same provided by the present disclosure, by virtue of “a copper foil carrier; a release layer formed on a side surface of the copper foil carrier; in which the release layer contains a copper-containing organic compound, and a chemical structure of the copper-containing organic compound has at least a Cu—N bond; and an ultra-thin copper foil layer formed on a side surface of the release layer away from the copper foil carrier,” the copper foil carrier and the ultra-thin copper foil layer have good release effect there-between.
Furthermore, the difficulty in controlling the peeling strength, attributed to the non-uniform distribution of thickness and the inconsistent content spread in the release layer, can be effectively improved.
The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others skilled in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope.
| Number | Date | Country | Kind |
|---|---|---|---|
| 112141938 | Nov 2023 | TW | national |
