KR102331091B1 - copper foil with carrier and copper-clad laminate - Google Patents

Abstract

A copper foil with carrier comprises a carrier and an ultra-thin copper layer deposited on the carrier, the ultra-thin copper layer comprising a release side against the carrier do. When the carrier is released from the ultra-thin copper layer, the material volume (Vm) of ^{the emitting surface is in the range of 0.09 to 0.27 μm 3} /μm ² , and the amount of nickel residue on the emitting surface is 60 μg /dm not greater than ²

Description

Copper foil with carrier and copper-clad laminate

The present disclosure relates to the field of electrodeposited copper foil, and more particularly, to an electrodeposited copper foil with a carrier and a copper-clad laminate thereof.

As the demand for small and thin electronic products capable of transmitting high-frequency signals increases, the demand for copper foils and copper clad laminates is also increasing. In general, the circuit of the copper clad laminate may be composed of a conductive wire such as a copper wire. Since the circuit has a specific layout, an electrical signal can be transmitted to a predetermined area along a predetermined path in the circuit. In addition, due to the continuous miniaturization of the line width/line spacing (L/S) of the conductive lines of the circuit, it is necessary to further reduce the thickness of the copper foil on the copper clad laminate, for example, to a fine line width/line spacing (L/S). In order to meet the demand for the copper foil, the thickness of the copper foil may be less than 9 μm. However, when the thickness of the copper foil is too thin, for example less than 5 μm, the mechanical strength is usually insufficient, resulting in breakage or cracking of the copper foil in the manufacturing process of the copper foil. Therefore, these copper foils may not meet the requirements. In order to solve the above-mentioned problems, an improved carrier-bearing copper foil has been developed in which a relatively thin copper layer is disposed on the carrier layer. Since the mechanical strength of the whole copper foil can be strengthened by using the carrier layer, the requirements for the manufacturing process of the copper foil can be satisfied.

In order to manufacture a copper-clad laminate with a conductive wire, when a copper foil with a carrier is adopted, the manufacturing process of the copper-clad laminate may include the following steps. First, a copper layer of copper foil with a carrier is laminated on an insulating board. Then, the carrier layer of the copper foil with the carrier is peeled off to expose the surface of the copper layer to obtain a copper clad laminate comprising an insulating board and a copper layer. Thereafter, a photoresist layer may be disposed on the exposed surface of the copper layer of the copper clad laminate, and then the photoresist layer is patterned through a photolithography process to form a patterned photoresist layer. A resist layer is formed. Then, to further pattern the copper layer, an etching process may be performed to transfer the pattern of the patterned photoresist layer to the underlying copper layer. Finally, the patterned photoresist layer is removed. By performing the above process, a copper clad laminate with a circuit can be obtained.

However, there remains a need to solve the technical disadvantages of the copper clad laminate having the circuit described above. During the process of transferring the pattern of the patterned photoresist layer to the underlying copper layer, for example, due to poor adhesion strength between the exposed surface of the copper layer and the patterned photoresist layer, the patterned photoresist layer It is easy to separate from the copper layer. Accordingly, the pattern of the patterned photoresist layer may not be completely and accurately transferred to the underlying copper layer. As a result, a patterned copper layer with undesired circuit layout and unsuitable line width/line spacing may be obtained.

Accordingly, without the aforementioned drawbacks, there remains a need for improved carrier-bearing copper foils and improved copper-clad laminates.

In consideration of this, the present disclosure provides a copper foil having an improved carrier capable of solving the disadvantages of the prior art, and a copper-clad laminate thereof.

According to one embodiment of the present disclosure, there is provided a copper foil with a carrier. The carrier-bearing copper foil includes a carrier layer and an ultra-thin copper layer disposed on the carrier foil, wherein the ultra-thin copper layer includes an emissive surface facing the carrier foil. When the carrier layer is peeled off from the ultra-thin copper layer, the material volume (Vm) on the ^{emitting surface is in the range of 0.09 to 0.27 μm 3} /μm ² , and the amount of nickel residue on the emitting surface is less than ^{60 μg/dm 2 .}

According to another embodiment of the present disclosure, a copper clad laminate is provided. The copper-clad laminate comprises a board and an ultra-thin copper layer disposed on at least one surface of the board, wherein the ultra-thin copper layer comprises an emissive face spaced from the surface of the board, the emissive face having a material volume of 0.09 to 0.27 μm ³ /μm ^{2 ,} and the amount of nickel residue on the emission surface is less than ^{60 μg/dm 2 .}

According to the above embodiments, the material volume of the emission side of the ultra-thin copper layer is in ^{the range of 0.09 to 0.27 μm 3} /μm ² , and the nickel residue on the emission side is less than ^{60 μg/dm 2 .} If the patterned photoresist layer is sequentially formed on the emitting surface of the ultra-thin copper layer, the adhesive strength between the emitting surface and the patterned photoresist layer can be sufficiently high. By improving the adhesive strength between the release surface of the ultra-thin copper layer and the patterned photoresist layer, during the process of transferring the pattern of the patterned photoresist layer to the underlying copper layer, it can not be easily peeled off from the surface of the ultra-thin copper layer. have. As a result, the pattern of the patterned photoresist layer can be completely and accurately transferred to the underlying ultra-thin copper layer, and a patterned ultra-thin copper layer having a desired circuit layout and fine line width/line spacing can be obtained.

These and other objects of the present invention will become apparent to those skilled in the art after reading the following detailed description, which is a preferred embodiment illustrated in the various drawings and figures.

BRIEF DESCRIPTION OF THE DRAWINGS The present disclosure will be better understood from the following description of exemplary implementations with reference to the accompanying drawings.
1 is a schematic cross-sectional view of a copper foil with a carrier according to an embodiment of the present disclosure.
2 is a schematic cross-sectional view of a copper clad laminate according to an embodiment of the present disclosure.
3 is a diagram illustrating a relationship between a surface height of an ultra-thin copper layer and a material ratio of an ultra-thin copper layer according to an embodiment of the present disclosure.
4 is a schematic cross-sectional view of a structure having an emitting surface and an anti-migration layer formed on one surface of a carrier layer according to an embodiment of the present disclosure;
5 is a schematic cross-sectional view of a structure having an electrodeposited copper layer and a roughening layer formed on one surface of a carrier layer according to an embodiment of the present disclosure;
6 is a schematic cross-sectional view of a structure having a patterned photoresist layer formed on one side of an ultra-thin copper layer according to an embodiment of the present disclosure.
7 is a schematic cross-sectional view of a structure with a patterned ultra-thin copper layer in accordance with an embodiment of the present disclosure.
8 is a schematic cross-sectional view of a structure after removal of a patterned photoresist layer according to an embodiment of the present disclosure.
The present disclosure is susceptible to various modifications and alternative forms. Some representative embodiments are shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the present invention is not limited to the specific form disclosed. Rather, this disclosure is intended to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention, as defined by the appended claims.

In order to provide those skilled in the art with a better understanding of the present disclosure, several exemplary embodiments of the present disclosure will be described in detail as follows, with reference to the accompanying drawings using numbered elements specifying the content and effects to be achieved. The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. Other implementations may be utilized and structural, logical, and electrical changes may be made without departing from the spirit and scope of the present disclosure.

In this disclosure, the meaning of "on", "above" and "over" means that "on" means something "directly on" as well as intermediate includes the meaning of "on" a feature or something layered thereon, and "on" or "over" means "on" or "over" something, as well as an intermediate feature or layer in between. It should be readily understood that something missing should be interpreted in its broadest way to include the meaning of "on" or "over" (ie, directly on something).

At a minimum, each numerical parameter should be interpreted in terms of the number of reported significant digits and should be interpreted using ordinary rounding methods. Ranges expressed herein may be expressed from one endpoint to another or between two endpoints. Unless otherwise specified, all ranges disclosed herein are inclusive of the endpoints.

It should be noted that technical features in other embodiments described below may be substituted, recombined or combined with each other to constitute other embodiments without departing from the spirit and scope of the present disclosure.

1 is a schematic cross-sectional view of a copper foil with a carrier according to an embodiment of the present disclosure. Referring to FIG. 1 , as shown in FIG. 1 , a copper foil with a carrier 100 includes at least a carrier layer 102 and an ultra-thin copper layer 104 . The ultra-thin copper layer 104 may be disposed on one side of the carrier layer 102 , and the emissive layer 106 and the anti-migration layer 108 may be disposed between the carrier layer 102 and the ultra-thin copper layer 104 . In the ultra-thin copper layer 104 , the electrodeposited copper layer 110 , the roughening layer 112 , the barrier layer 114 , and the coupling layer 116 are sequentially stacked. In the present disclosure, the term “ultra-thin copper layer” may refer to a “copper-containing composite layer having a thickness of 5 μm or less”, for example, a copper-containing composite layer having a thickness of 0.2 μm to 3.5 μm.

The carrier layer 102 may be a metal layer formed through electrolytic deposition (also called electrolysis, electrodeposition or electroplating). The composition of the carrier layer 102 may include, but is not limited to, copper, aluminum, iron, nickel, or alloys thereof. The carrier layer 102 may have a deposition surface 102A and a drum surface 102B opposite to the deposition surface 102A, the 10-point average of the deposition surface 102A, defined according to JIS B 0601-1994. The roughness Rz may be higher than that of the drum surface 102B. The thickness of the carrier layer 102 is not limited as long as it can support the ultra-thin copper layer 104 and provide sufficient mechanical strength. For example, the thickness of the carrier layer 102 may range from 18 μm to 35 μm.

The release layer 106 and the anti-migration layer 108 may be sequentially disposed on the deposition surface 102A or the drum surface 102B of the carrier layer 102 . The release layer 106 may be an adhesion promoting layer, which is used to suitably adjust the adhesion strength between the carrier layer 102 and the ultra-thin copper layer 104 . By using the release layer 106, the carrier layer 102 can be adhered to the ultra-thin copper layer 104, but the release layer 106 makes the carrier layer 102 difficult from the ultra-thin copper layer 104 in a subsequent process. It may not cause peeling. For example, the composition of the emissive layer 106 may include a heteroaromatic compound such as 1,2,3-benzotriazole, carboxybenzotriazole (CBTA), N′,N′-bis(benzotriazolemethyl)urea, 1H-1,2,4-triazole, or 3-amino-1H-1,2,4-triazole. Also, the movement preventing layer 108 and the electrodeposited copper layer 110 may have different compositions. For example, the movement preventing layer 108 may be a nickel-containing layer, and the composition thereof may be pure nickel, a nickel-containing inorganic dopant, or a nickel-containing alloy, but is not limited thereto. Some metals that may be alloyed with nickel may be, but are not limited to, cobalt, tungsten, molybdenum, zinc, tin, chromium, or iron. It should be noted that, according to some embodiments, the anti-migration layer 108 may optionally be omitted.

An electrodeposited copper layer 110 of an ultra-thin copper layer 104 , a roughening layer 112 , a barrier layer 114 , and a coupling layer 116 are sequentially disposed on the carrier layer 102 . Both the emissive layer 106 and the anti-migration layer 108 may be disposed between the carrier layer 102 and the ultra-thin copper layer 104 . The electrodeposited copper layer 110 is a copper layer formed on the carrier layer 102 by an electrodeposition process, and the thickness thereof is usually 5 μm or less. The roughening layer 112 may be a single layer or multiple copper layers, which may include nodules. The purpose of the roughening layer 112 is to increase the surface roughness of the ultra-thin copper layer 104 . The barrier layer 114 may be a metal layer or a metal alloy layer. The composition of the above-mentioned metal layer may be nickel, zinc, chromium, cobalt, molybdenum, iron, tin, or vanadium, such as a nickel layer, a nickel-zinc alloy layer, a zinc layer, a zinc-tin alloy layer, or a chromium layer, but is not limited thereto. does not Further, the metal layer and the metal alloy layer may have a single-layer or multi-layer structure, for example, a single layer containing zinc and/or nickel. When the metal layer has a multi-layer structure, the stacking order of the sub-layers may be changed according to different requirements without specific limitations. For example, the zinc-containing layer may be deposited on the nickel-containing layer, or the nickel-containing layer may be deposited on the zinc-containing layer. The coupling layer 116 may be composed of silane, which is 3-aminopropyltriethoxysilane (APTES), N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, (3-glycidyl). Oxypropyl) triethoxysilane, (8-glycidyloxyoctyl) trimethoxysilane, methacryloyl propyltriethoxysilane, methacryloyl octyltrimethoxysilane, methacryloyl propyltrimethoxy silane, (3-mercaptopropyl)trimethoxysilane, (3-glycidyloxypropyl)trimethoxysilane, but is not limited thereto. The purpose of the coupling layer 116 is to increase the adhesive strength between the ultra-thin copper layer 104 and other adjacent materials (eg, a board).

The ultra-thin copper layer 104 also has an emitting surface 104A facing the carrier layer 102 and a lamination surface 104B facing the emitting surface 104A. Unless otherwise specified, the release surface 104A disclosed herein refers to the exposed surface of the ultra-thin copper layer 104 when the carrier layer 102 is peeled from the ultra-thin copper layer 104 . When the carrier layer 102 is peeled from the ultra-thin copper layer 104 , the material volume Vm of the release surface 104A is in ^{the range of 0.09 to 0.27 μm 3} /μm ² , and the nickel residue on the release surface 104A is the amount no greater than 60μg / dm ^2, preferably from 25 to the range of 54μg / dm ^2. Moreover, the 10-point average roughness Rz of the lamination|stacking surface 104B exists in the range of 0.7-1.9 micrometers. For the material volume (Vm) and void volume (Vv) of the layered surface 104B and the difference between the two, the material volume (Vm) of the layered surface 104B is in the range ^{of 0.25 to 0.37 μm 3} /μm ^{2 ,} The pore volume (Vv) of 104B is in ^{the range of 0.28 to 0.47 μm 3} /μm ² , and the difference between the material volume (Vm) and the void volume (Vv) of the layered surface 104B is 0.01 to 0.14 ^{μm 3} /μm ² is in the range of According to one embodiment of the present disclosure, the outer surface of the coupling layer 116 is the lamination surface 104B of the ultra-thin copper layer 104 .

2 is a schematic cross-sectional view of a copper clad laminate according to an embodiment of the present disclosure. The copper-clad laminate 200 includes at least an ultra-thin copper layer 104 and a board 118 , wherein the laminated surface 104B of the ultra-thin copper layer 104 faces and directly contacts the board 118 . The structure shown in FIG. 2 can be obtained by heat-pressing a copper foil with the carrier 100 shown in FIG. 1 . When the carrier layer 102 is peeled from the ultra-thin copper layer 104 , the emitting surface 104A of the ultra-thin copper layer 104 may be exposed. The material volume Vm of the exposed release face 104A is in ^{the range of 0.09 to 0.27 μm 3} /μm ² , and the amount of nickel residue on the exposed release face 104A is not greater than ^{60 μg/dm 2 .}

3 is a diagram illustrating a relationship between a surface height of an ultra-thin copper layer and a material ratio (mr) of an ultra-thin copper layer according to an embodiment of the present disclosure. The material volume (Vm) and pore volume (Vv) disclosed herein are defined according to ISO 25178-2 (2012), and the measurement results are shown in FIG. 3 . In particular, referring to FIG. 3 , the material volume Vm 304 is calculated by integrating the volume of the material surrounded by the curve (upper boundary) and the horizontal cut line (lower boundary) shown in FIG. 3 . The z-axis position of the horizontal cutting line is set to a height corresponding to a specific point on the curve, where the material ratio mr at the specific point may be P2. Accordingly, the material volume Vm 304 is the area enclosed by the curve and the horizontal cut line shown in FIG. 3, where the material ratio mr is in the range of 0% to 80% (P2). Unless otherwise specified, the volume of material (Vm) disclosed herein is an integral, wherein the ratio of material (mr) is in the range of 0% to 80%, i.e., the ratio of material (mr) of volume of material (Vm) is set at 80%. Note that it refers to a value.

The void volume (Vv) 302 is calculated by integrating the volume of the void surrounded by the curve (lower bound) and the horizontal cut line (upper bound) shown in FIG. 3 . The z-axis position of the horizontal cutting line is set to a height corresponding to a specific point on the curve, where the material ratio mr at the specific point may be P1. Thus, the void volume (Vv) 302 is the area enclosed by the curve and the horizontal cut line shown in FIG. 1 , where the material ratio mr is in the range of 10% (P1) to 100%. Note that, unless otherwise specified, the pore volume (Vv) disclosed herein refers to an integral value with the material ratio (mr) in the range of 10% to 100%, i.e., the pore volume (Vv) is set to 10%. Should be.

Specifically, according to some embodiments of the present disclosure, the material volume (Vm) of the emission surface 104A of the ultra-thin copper layer 104 is in ^{the range of 0.09 to 0.27 μm 3} /μm ² , and the nickel of the emission surface 104A is in the range of 0.09 to 0.27 μm 3 /μm 2 . The amount of residue is not greater than ^{60 μg/dm 2 .} When the patterned photoresist layer is sequentially formed on the emitting surface 104A of the ultra-thin copper layer 104, the emitting surface 104A and the patterned photoresist layer may have better adhesion strength. By improving the adhesion strength between the emitting surface 104A of the ultra-thin copper layer 104 and the patterned photoresist layer, during the process of transferring the pattern of the patterned photoresist layer to the underlying ultra-thin copper layer 104, the pattern The photoresist layer may not be easily peeled off from the surface of the ultra-thin copper layer 104 . As a result, the pattern of the patterned photoresist layer can be completely and accurately transferred to the lower ultra-thin copper layer 104, and a patterned ultra-thin copper layer having a desired circuit layout and fine line width/line spacing can be obtained. .

Further, according to some embodiments of the present disclosure, the 10-point average roughness (Rz) of the lamination surface 104B of the ultra-thin copper layer 104 is in the range of 0.7 to 1.9 μm, and the material volume (Vm) of the lamination surface 104B ) and the difference between the pore volume (Vv) is in the range of ^{0.01 to 0.14 μm 3} /μm ^{2 .} Due to these surface properties, the peel strength between the ultra-thin copper layer 104 and the board 118 is higher than 3 lb/in, which indicates that the patterned ultra-thin copper layer 104 is removed from the board 118 during the process of transferring the pattern. This means that the chances of delamination are much lower.

The manufacturing method of the copper foil with a carrier, a copper-clad laminated board, and a copper-clad laminated board with a circuit is further demonstrated as an example.

4 is a schematic cross-sectional view of a structure having an emitting layer and a movement preventing layer formed on one surface of a carrier layer according to an embodiment of the present disclosure. Referring to FIG. 4 , a carrier layer 102 , such as a copper-containing carrier layer, may be formed on the surface of the metal cathode drum by an electrodeposition process. One side of the carrier layer 102 that is spaced from the metal cathode drum may be considered the deposition side 102A, and the other side of the carrier layer 102 facing the metal cathode drum may be considered the drum side 102B. Then, the release layer 106 and the anti-migration layer 108 are sequentially disposed on the drum face 102B of the carrier layer 102 . In particular, the release layer 106 may be disposed on the carrier layer 102 by an immersion process, and the anti-migration layer 108 may be disposed on the release layer 106 by an electrodeposition process.

5 is a schematic cross-sectional view of a structure having an electrodeposited copper layer and a roughening layer formed on one side of a carrier layer according to an embodiment of the present disclosure; After the formation of the movement prevention layer 108, an ultra-thin copper layer 104 including an electrodeposited copper layer 110, a roughening layer 112, and a barrier layer 114 on the surface of the movement prevention layer 108 may be formed. have. In this manufacturing step, by performing an electrodeposition process, the electrodeposited copper layer 110 of the ultra-thin copper layer 104 , the roughening layer 112 and the barrier layer 114 are sequentially formed on the surface of the movement preventing layer 108 . can be Then, the coupling layer 116 is coated on the barrier layer 114, and the structure shown in FIG. 1 can be obtained.

Then, the copper foil with the carrier 100 can be heat-pressed into a board, and the carrier layer 102 of the copper foil 100 is peeled off from the ultra-thin copper layer 104 to release the ultra-thin copper layer 104 ( 104A) may be exposed. As a result, a structure similar to the copper clad laminate 200 shown in FIG. 2 can be obtained. It should be noted that when the carrier layer 102 is peeled from the ultra-thin copper layer 104 , a portion of the anti-migration layer 108 , such as a nickel residue, may remain on the release surface 104A of the ultra-thin copper layer. The remaining nickel residue may be considered part of the exit surface 104A of the ultra-thin copper layer 104 . In addition, since the total thickness of the release layer 106 and the anti-migration layer 108 is extremely thin, when the ultra-thin copper layer 104 is formed by an electrodeposition process, the emission surface 104A of the ultra-thin copper layer 104 is The surface topography is dominated by the carrier layer 102 . That is, any one of factors such as the surface topography of the carrier layer 102 , or the composition of the electrolyte or the electrodeposition conditions for forming the carrier layer 102 , can affect the surface topography of the emitting surface 104A. have. In other words, the surface topography of the emitting surface 104A can be controlled by adopting a carrier layer having a desired surface topography, adjusting the composition of the electrolyte solution, or controlling the electrodeposition process conditions.

The board 118 may be, but is not limited to, a bakelite board, a polymer board, or a fiberglass board. In the case of a polymer board, its composition is, for example, an epoxy resin, a phenol resin, a polyester resin, a polyimide resin, an acrylic, a formaldehyde resin, a bismaleimide triazine resin (BT resin), a cyanate ester resin, a fluoropolymer, polyether sulfone, cellulosic thermoplastic, polycarbonate, polyolefin, polypropylene, polysulfide, polyurethane, polyimide, liquid crystal polymer (LCP), or polyphenylene oxide (PPO). In the case of a glass fiber board, the glass fiber board may be a prepreg formed by immersing a nonwoven glass fiber fabric in the polymer-containing solution (epoxy resin-containing solution).

6 is a schematic cross-sectional view of a structure with a patterned photoresist layer on one side of an ultra-thin copper layer according to an embodiment of the present disclosure. After formation of the copper clad laminate 200 shown in FIG. 2 , a photoresist layer, such as a dry film photoresist, may be disposed on the emitting surface 104A of the ultra-thin copper layer 104 of the copper clad laminate 200 . By performing an appropriate photolithography process, the photoresist layer can be patterned to become the patterned photoresist layer 320 . The patterned photoresist layer 320 may have a pattern, for example, a circuit pattern.

7 is a schematic cross-sectional view of a structure having a patterned ultra-thin copper layer in accordance with an embodiment of the present disclosure. After formation of the patterned photoresist layer 320 , an appropriate etching process, such as a wet etching process, may be performed to transfer the circuit pattern defined in the patterned photoresist layer 320 to the lower ultra-thin copper layer 104 . have. When the etching process is completed, a patterned ultra-thin copper layer 410 composed of a pattern of conductive lines 412 and a pattern of gaps 414 can be obtained. According to one embodiment of the present disclosure, since the adhesive strength between the emitting surface 104A of the ultra-thin copper layer 104 and the patterned photoresist layer is sufficiently high, the pattern of the patterned photoresist layer 320 is lowered. During the process of transferring to the ultra-thin copper layer 104 , the patterned photoresist layer 320 may not easily peel off from the surface of the ultra-thin copper layer 104 . As a result, the pattern of the patterned photoresist layer 320 can be completely and accurately transferred to the lower ultra-thin copper layer 104, and the patterned ultra-thin copper layer 410 with the desired circuit layout and line width/line spacing. ) and the corresponding copper clad laminate 400 can be obtained. Accordingly, when the disclosed manufacturing process is completed, the copper clad laminate 400 can be obtained.

8 is a schematic cross-sectional view of a structure after removal of a patterned photoresist layer according to an embodiment of the present disclosure. After formation of the copper clad laminate 400 shown in FIG. 7 , the patterned photoresist layer 320 is removed to expose the emission surface 104A of the ultra-thin copper layer 104 . According to one embodiment of the present disclosure, since the peel strength between the ultra-thin copper layer 104 and the board 118 is greater than 3 lb/in, during the process of removing the patterned photoresist layer 320 , the patterned The ultra-thin copper layer 410 may not easily peel off the board 118 . In other words, the conductive lines 412 and spacing 414 of the ultra-thin copper layer 410 having a desired pattern can be fabricated on the board 118 without departing from a predetermined layout.

To enable a person skilled in the art to implement the present disclosure, specific embodiments of a copper foil with a carrier and a copper clad laminate are described in more detail below. However, it should be noted that the following examples are for illustrative purposes only and should not be construed as limiting the present disclosure. That is, the materials, amounts and proportions of materials, and process flows in each embodiment may be appropriately modified as long as these variations fall within the spirit and scope of the present invention, as defined by the appended claims. .

In particular, according to the following Examples and Comparative Examples, the manufacturing process of the copper foil and the copper clad laminate with a carrier, the surface roughness (Rz, Vv, Vm) of the copper foil with the carrier, the adhesive strength between the photoresist layer and the copper clad laminate, and the ultra-thin The peel strength between the copper layer and the lower board is disclosed, and the parameters and test results are shown in Tables 1 and 2 below.

Example

Example 1

<i. Preparation of carrier layer>

A copper wire was dissolved in a sulfuric acid aqueous solution (50 wt%) _{to prepare a copper sulfate electrolyte solution containing 320 g/L copper sulfate (CuSO 4} ·5H ₂ O) and 110 g/L sulfuric acid. Per liter of copper sulfate electrolyte, 5.5 mg of low-molecular weight gel (SV, manufactured by Nippi, Inc.), 3 mg of sodium 3-mercaptopropane sulfonate (MPS, manufactured by Hopax Chemicals Manufacturing Company Ltd.), 25 mg of hydrochloric acid (RCI) Labscan Ltd.) was added.

Then, at a liquid temperature of 50° C. and ^{a current density of 50 A/dm 2} , an electrodeposited copper foil having a thickness of 18 μm (or referred to as 'electroplating') was prepared. A typical apparatus for making copper foil comprises a metal cathode drum and an insoluble metal anode, the metal cathode drum being rotatable and having a mirror polished surface. According to JIS G 0552, the grain size number of the mirror polished surface is 7. An insoluble metal anode was placed approximately in the lower half of the metal cathode drum and wrapped around the metal cathode drum. Copper foil was continuously produced with the apparatus by flowing a copper electrolyte solution between the cathode drum and the anode, applying an electric current between them to electrodeposit copper on the cathode drum, and detaching the electrodeposited copper foil from the cathode drum. The electrodeposited copper foil can be used as a carrier layer in the next process.

<ii. Preparation of Emissive Layer>

An electrodeposited copper foil having a thickness of 18 µm (also referred to as a 'carrier layer') was immersed in a 1000 ppm carboxybenzotriazole (CBTA) solution at a temperature of 30° C. for 30 seconds. As a result, an emission layer was formed on the carrier layer.

<iii. Preparation of migration prevention layer>

Using an electrolyte containing 300 g/L of nickel sulfate (NiSO ₄ .7H ₂ O) and 40 g/L of boric acid (H ₃ BO ₃ ), at a temperature of 50° C. and a current density of ^{4 A/dm 2 for 1 second} , an anti-migration layer was optionally disposed on the emitting side on the drum side of the carrier layer. For Example 1, there was no anti-migration layer disposed on the carrier layer.

<iv. Preparation of Electrodeposited Copper Layer>

A copper wire was dissolved in a 50wt% aqueous solution _{of sulfuric acid to prepare a copper sulfate electrolyte containing 320 g/L of copper sulfate (CuSO 4} ·5H ₂ O) and 110 g/L of sulfuric acid. Per 1 liter of the copper sulfate electrolyte solution, 5.5 mg of low-molecular-weight gel (SV, manufactured by Nippi, Inc.), 3 mg of sodium 3-mercaptopropane sulfonate (MPS, manufactured by Hopax Chemicals Manufacturing Company Ltd.), 25 mg of hydrochloric acid ( manufactured by RCI Labscan Ltd.), 9.5 mg of PEI (polyethylenimine, linear, Mn=5000, commercially available from Sigma-Aldrich Company) and 6.8 mg of saccharin (1,1-dioxo-1,2-benzothiazole-3) -on, commercially available from Sigma-Aldrich Company) was added.

After preparation of the copper-containing electrolytic solution, a copper layer electrodeposited by an electrodeposition process is prepared. During electrodeposition, the electrolyte was maintained at a temperature of 50° C. and the current density was maintained at ^{20 A/dm 2 .} The plating time was 45 seconds. As a result, an electrodeposited copper layer having a thickness of 3 μm was added on the movement preventing layer on the drum surface of the carrier layer.

<v. Preparation of Roughening Layer>

Using a copper sulfate electrolyte containing 95 g/L copper sulfate (CuSO ₄ .5H ₂ O), 115 g/L sulfuric acid, and 3.5 ppm chloride ions, a roughening layer (eg, copper nodules) was applied onto the electrodeposited copper layer. , was added, using a current density of ^{50 A/dm 2} for 10 s at a temperature of 25°C.

In addition, a copper cover layer was formed on the copper nodules using an electrodeposition process to prevent peeling of the copper nodules. In the electrodeposition process for forming the copper cover layer, copper sulfate electrolytes having copper sulfate and sulfuric acid concentrations of 320 g/L and 100 g/L, respectively, were used. The temperature of the electrolyte was maintained at 40 °C, and the current density was maintained at 15A/dm ² for 10 seconds.

<vi. Preparation of barrier layer>

180 g/L of nickel sulfate (NiSO ₄ .7H ₂ O) and 3.6 g/L of sodium hypophosphite (NaH ₂ PO ₂ ) By performing an electrodeposition process using a nickel sulfate electrolyte (pH=3.5), A nickel-containing layer was added on the roughening layer using a current density of ^{0.2 A/dm 2} at a temperature of 20° C. for 3 seconds. When the formation of the nickel-containing layer was completed, washing was performed with water.

Then, an electrodeposition process was performed using a zinc sulfate electrolyte containing 100 g/L of zinc sulfate maintained at pH = 3.4 and a temperature of 50° C., thereby using a current density of ^{4 A/dm 2 for 2 seconds.} A zinc-containing layer was added on two opposite surfaces of When the formation of the zinc-containing layer was completed, washing was performed with water.

Further, by carrying out the electrodeposition process using a chromic acid bath containing 5 g/L of chromic acid, maintained at a temperature of 35° C., pH=11.5, ² of the copper foil using a current density of 10 A/dm 2 for 5 seconds A chromium-containing layer was added on the opposite side of the dog.

<vii. Preparation of Coupling Layer>

When the passivation treatment was completed, the copper foil was washed with water. Then, the copper foil was put into the chamber for a silane coupling agent process, without drying the copper foil surface. In this treatment, the concentration of the solution was 0.25 wt % 3-aminopropyltriethoxysilane (APTES), and the solution was sprayed on top of the barrier layer to make the surface of the barrier layer absorb the silane coupling agent. The silane coupling agent was disposed on a specific side of the copper carrier layer (ie, the side with the roughening layer), and the silane coupling agent constituted the coupling layer.

After completing the above process, a copper foil with a carrier of Example 1 was obtained. The electrodeposited copper layer, roughening layer, barrier layer and coupling layer were considered as composite layers called ultra-thin copper layer. The outer surface of the coupling layer was regarded as the laminated surface of the copper foil with the carrier.

Example 2-18

The manufacturing process of Example 2-18 was substantially the same as that of Example 1. Preparation parameters different from those of Example 1 are shown in Tables 1 and 2 below. In particular, Examples 2-9 did not provide the anti-migration layer, but Examples 10-18 provided the anti-migration layer.

Comparative Example 1-10

The manufacturing process of Comparative Examples 1-10 was substantially the same as that of Example 1. Preparation parameters different from those of Example 1 are shown in Tables 1 and 2 below. In particular, Comparative Examples 1-4 did not provide a migration preventing layer, but Comparative Examples 5-10 provided a migration preventing layer.

test method

The test pieces of Examples and Comparative Examples were further tested or measured by the following test method, and the results are shown in Tables 1 and 2 below.

<void volume (Vv) and material volume (Vm)>

The void volume (Vv) and material volume (Vm) of the surface of copper foils and ultra-thin copper layers were measured according to ISO 25178-2 (2012) using surface texture analysis of a laser microscope. The laser microscope was LEXT OLS5000-SAF manufactured by Olympus, and the light source was a 405 nm wavelength source. The objective lens was 100 x magnification (MPLAPON-100xLEXT). Optical zoom was set to 1.0 x. The image area was set to 129 μm×129 μm. The resolution was set to 1024 pixels x 1024 pixels. The condition was set to auto tilt removal and the filter setting was set to unfiltered. Images were prepared at an air temperature of 24 ± 3 °C and a relative humidity of 63 ± 3%. As listed in Tables 1 and 2, the values of material volume (Vm) and pore volume (Vv) were calculated as material ratio (mr) at 80% and 10%, respectively. The units of substance (Vm) and pore volume (Vv) were μm³/μm².

<Material volume at the emission surface (Vm)>

The copper foil with a carrier was laminated on the BT resin (GHPL-830NX type A, Mitsubishigas chemical co.) with the lamination surface of the copper foil facing the BT resin. Lamination conditions were as follows: temperature: 233 °C, pressure: 580 psi, and pressurization time: 100 min. Then, the carrier layer of the copper foil was peeled off to expose one side of the ultra-thin copper layer, that is, the release side of the ultra-thin copper layer. The material volume (Vm) of the emission surface of the ultra-thin copper layer was measured by performing the measurements described in <Volume of the void (Vv) and Volume of the material (Vm)>.

<10-point average roughness of the emission surface (Rz)>

According to JIS B 0601-1994, the 10-point average roughness (Rz) of the laminated surface of the copper foil was detected using a surface roughness meter (SE 600 series; Kosaka Laboratory Ltd). The measurement conditions were as follows. The diameter of the tip of the stylus was 2 μm, and the cone angle of the tip was 90°. A profile filter having an evaluation length of 4.0 mm and a cutoff value (λc) of 0.8 mm was applied.

<Amount of Nickel Residue on Release Surface>

The copper foil with the carrier was cut to obtain a 150 mm x 150 mm test piece, and two polyimide protective layers were placed on the outer surfaces of the carrier layer and the ultra-thin copper layer, respectively (the polyimide protective layer prevents the underlying copper from dissolving) box). The carrier layer is then peeled off from the ultra-thin copper layer to expose one side of the ultra-thin copper layer (ie, the emitting side of the ultra-thin copper layer). The test piece was further cut to a size of 100 mm x 100 mm (area = 1 dm ^{2 ).} Then, the test piece was placed in a dish, and 20 ml of 18% HCl solution and 3 ml of 30% H ₂ O ₂ solution were added to the dish. The test piece was immersed for 10 minutes at a solution temperature of 25°C. After the nickel on the discharge side of the ultra-thin copper layer was completely dissolved, the solution was poured into a 50 ml volumetric flask. The dishes were washed with water and the volumetric flask collected wash water until the solution in the volumetric flask reached its final volume (ie 50 ml). The amount of nickel was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES) (iCAP7000; Thermo Co.).

<Photoresist pattern adhesion>

The copper foil with a carrier was laminated on the BT resin (GHPL-830NX type A, Mitsubishigas chemical co.) with the lamination surface of the copper foil facing the BT resin. Lamination conditions were as follows: temperature: 233 °C, pressure: 580 psi, and pressurization time: 100 min. The carrier layer was then peeled from the electrodeposited copper layer to expose the release side of the ultra-thin copper layer. After that, the exposed surface of the ultra-thin copper layer was laminated with a photoresist dry film (FF-9030A, Chang Chun plastics co.) to form a laminate, and the lamination conditions were 65 °C, 3.0 kg/cm ² , and 3 seconds. it was

After lamination with a photoresist dry film, the lamination was cooled at room temperature for 15 minutes. Then, a photomask (L/S = 1/1, straight pattern, width 20-50 μm) was covered on the surface of the stack, and the stack was subjected to an ORC EXM-1201F exposure machine under an energy of ^{mJ/cm 2 for 15 minutes.} exposed. When the exposure process was completed, a portion of the photoresist dry film was cured.

After exposure, the exposed stack was cooled at room temperature for 15 minutes. Next, the uncured dry film was washed by spraying a developer on the dry film to develop a line pattern. Washing conditions were 29 °C, 1.0 wt% Na ₂ CO ₃ , and the spray pressure was 1.2 kg/cm ² .

Then, the sample was etched with an etching solution, and the pattern shown on the patterned dry film was transferred to the lower electrodeposited copper layer. The etching solution was prepared by mixing 36wt% HCl solution, 40wt% FeCl ₃ solution, and purified water ( _{volume ratio of HCl solution, FeCl 3} solution and purified water is 1:1:1). Upon completion of the etching process, a patterned ultra-thin copper layer was prepared.

A variety of photomasks can be used to obtain patterned ultra-thin copper layers with different patterns (eg, line patterns with specific widths). For example, a set of samples was prepared 5 μm apart (e.g., 20 μm for the first set, 25 μm for the second set, 30 μm for the third set, etc.), and each set contains 5 samples with the same line width. included.

When the etching process of the electrodeposited copper layer was completed, each set of cured dry film was observed to ensure that the cured dry film of 5 samples of the same set was separated from the etched, electrodeposited copper layer. The observation was used to evaluate the adhesive strength between the cured photoresist dry film and the electrodeposited copper layer. The criteria for photoresist pattern adhesion are as follows:

Grade A: Grade A: Sets with line width ≤ 30 μm pass the test (all 5 samples in a specific set, the cured dry film does not separate from the etched copper layer).

Grade B: One set with a width ≤ 30 μm does not pass the test (part of the cured dry film of the five samples in the specified set separates from the etched copper layer). Another set with a width >30 μm passed the test (not all cured dry films of 5 samples of a particular set separated from the etched copper layer).

<Peel strength>

A copper clad laminate was obtained by laminating a copper foil with a carrier on a BT resin (GHPL-830NX type A, Mitsubishigas chemical co.) with the lamination surface of the copper foil facing the BT resin. Lamination conditions were as follows: temperature: 233 °C, pressure: 580 psi, and pressurization time: 100 min.

Then, the carrier layer was peeled off from the ultra-thin copper layer to expose one side of the ultra-thin copper layer (ie, the emitting side of the ultra-thin copper layer). Then, an additional copper layer with a thickness of 32 μm was electrodeposited on the release side of the ultra-thin copper layer, so that the total thickness of the additional copper layer and the lower ultra-thin copper layer reached 35 μm.

Finally, a 35 μm copper layer (including an additional copper layer and a lower ultra-thin copper layer) was simultaneously peeled from the BT resin using a universal testing machine, and then the peel strength was analyzed.

[Table 1]

[Table 1-Continued]

[Table 2]

[Table 2 - Continued]

According to Examples 1-18, the material volume (Vm) of the emission side of the ultra-thin copper layer was in ^{the range of 0.09 to 0.27 μm 3} /μm ² , and the nickel residue on the emission side was less than ^{60 μg/dm 2 .} Then, when a patterned photoresist layer is formed on the emitting surface of the ultra-thin copper layer, the peel strength between the emitting surface and the patterned photoresist layer can reach grade A, which is grade B of Comparative Examples 1-10 was better. By improving the peel strength between the emitting surface of the ultra-thin copper layer and the patterned photoresist layer, the patterned photoresist layer is formed into the ultra-thin copper layer during the process of transferring the pattern of the patterned photoresist layer to the underlying copper layer. There was little possibility of peeling from the surface of As a result, the pattern of the patterned photoresist layer could be completely and accurately transferred to the lower ultra-thin copper layer, and a patterned ultra-thin copper layer having the desired circuit layout and line width/line spacing was obtained.

Further, according to Examples 1-7 and 10-16, when the 10-point average roughness (Rz) of the lamination surface of the ultra-thin copper layer is in the range of 0.7 to 1.9 μm, the material volume (Vm) and the void volume ( Vv) is in ^{the range of 0.01 to 0.14 μm 3} /μm ² , and the peel strength between the ultra-thin copper layer and the BT resin board is greater than 3 lb/in, which is the peel strength of Comparative Examples 2 and 6 (i.e., 2.1 lb/in ) is greater than Thus, high peel strength means that the patterned ultra-thin copper layer is much less likely to peel from the resin board.

Those skilled in the art will readily appreciate that numerous modifications and variations of the apparatus and method may be made while maintaining the teachings of the present invention. Accordingly, the above disclosure should be construed as being limited only by the scope and boundaries of the appended claims.

Claims (10)

As a copper foil with a carrier,
a carrier layer, and
an ultra-thin copper layer disposed on the carrier layer, the ultra-thin copper layer comprising an emissive surface facing the carrier layer;
After the carrier layer is peeled off from the ultra-thin copper layer, the material volume (Vm) of ^{the release surface is in the range of 0.09 to 0.27 μm 3} /μm ² , and the amount of nickel residue on the release surface is 60 μg/dm ² is less than,
The material volume (Vm) of the emission surface is a value calculated by the material ratio (material ratio, mr) in the range of 0% to 80%, copper foil with a carrier. According to claim 1,
The ultra-thin copper layer is
Further comprising a lamination surface opposite the emitting surface,
10-point average roughness (Rz) of the laminated surface is 0.7 to 1.9 μm,
The difference between the material volume (Vm) and the void volume (Vv) of the layered surface is 0.01 to 0.14 ^{μm 3} /μm ² ,
The material volume (Vm) of the lamination surface is a value calculated as the material ratio (mr) in the range of 0% to 80%, and the void volume (Vv) of the lamination surface is the material ratio ( Copper foil with carrier, a value calculated as material ratio (mr). 3. The method of claim 2,
The void volume (Vv) of the laminated surface is in ^{the range of 0.28 to 0.47 μm 3} /μm ² , copper foil with a carrier. 3. The method of claim 2,
The material volume (Vm) of the laminated surface is in ^{the range of 0.25 to 0.37 μm 3} /μm ² , copper foil with a carrier. 3. The method of claim 2,
The ultra-thin copper layer is
Further comprising a roughening layer, a barrier layer, and a coupling layer disposed sequentially,
The outer surface of the coupling layer is the laminated surface, and the 10-point average roughness (Rz) of the laminated surface is greater than the 10-point average roughness (Rz) of the emitting surface, copper foil with a carrier. According to claim 1,
Further comprising an anti-migration layer disposed between the carrier layer and the ultra-thin copper layer,
The composition of the movement preventing layer is different from the composition of the ultra-thin copper layer, copper foil with a carrier. 7. The method of claim 6,
The composition of the anti-movement layer includes nickel, copper foil with a carrier. 8. The method of claim 7,
After the carrier layer is peeled off from the ultra-thin copper layer, the amount of nickel residue on the release surface is in ^{the range of 25 to 54 μg/dm 2} Copper foil with a carrier. According to claim 1,
Further comprising a peeling layer disposed between the carrier layer and the ultra-thin copper layer,
The composition of the release layer includes a heteroaromatic compound, copper foil with a carrier. As a copper-clad laminate
a board, and
an ultra-thin copper layer disposed on at least one surface of the board, wherein the ultra-thin copper layer comprises an emissive surface spaced apart from the at least one surface of the board, the emissive surface having a material volume (Vm) of 0.09 to 0.27 μm ³ /μm ² , wherein the amount of nickel residue on the emitting surface is less than ^{60 μg/dm 2 ,}
The material volume (Vm) of the emitting surface is a value calculated by the material ratio (mr) in the range of 0% to 80%, the copper clad laminate.

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