KR100454270B1 - Low Roughness Electrodeposited Copper Foil Manufacturing Method And Electrodeposited Copper Foil Thereby - Google Patents

Abstract

The present invention relates to a method of manufacturing a low-light electrolytic copper foil and an electrolytic copper foil, using an electrolyte solution based on sulfuric acid, copper ions, and chlorine ions, and adding an additive thereto. The additive used in the present invention is 0.05 to 50 ppm of HEC (Hydroxyethyl Cellulose), 0.05-20ppm SPS (bis (sodiumsulfopropyl) disulfide) and 0.1-100ppm gelatin. It can be used as a material and electrode material for lithium ion batteries.

Description

Low Roughness Electrodeposited Copper Foil Manufacturing Method And Electrodeposited Copper Foil Thereby}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electrodeposited copper foil adhered to an insulator substrate for a printed circuit board (PCB), and more particularly, to the roughness of the matte side of the electrolytic copper foil ( The present invention relates to a manufacturing method for lowering roughness so that no residual material remains even when forming a fine pattern, and an electrolytic copper foil manufactured by the manufacturing method.

Generally, printed circuit boards are widely used for precision control of consumer electronic / electronic products such as radios, televisions, washing machines, VTRs, and industrial electronic / electronic devices such as computers, wireless communication devices, and various control devices. Flame retardant prepreg in which glass fiber is impregnated with epoxy resin is used as insulation board of industrial printed circuit, and the electrolytic copper foil for printed circuit is bonded to this insulation board under high temperature and high pressure. Etched according to the design to obtain a printed circuit board.

Electrolytic copper foil adhered to an insulating substrate is generally a rough foil in the copper sulfate solution to form a raw foil (copper nodule) on the surface of the sister foil to improve the adhesion with the insulating substrate Electrolytic copper foil is obtained by forming a barrier layer on the surface which has been plated or roughened and then electrolytic chromate rust treatment. In the case of preparing the brother foil by the continuous electrolytic electrodeposition method, the surface of the drum face, which is usually the negative electrode, is called the Shiny side, and the surface of the electrolyte side is called the Matte side.

In recent years, as the light and thin shortening of electrical and electronic devices is accelerated, printed circuit boards have been miniaturized and highly integrated and miniaturized. Accordingly, ultra-low roughness copper foils suitable for precision printed circuit boards have been developed by strengthening the manufacturing method of substrates and printed circuits.

As a technique for manufacturing a conventional electrolytic copper foil, the first method is to obtain a low light copper foil by dividing the section to be electrolytically and increasing the current density of the second section than the first section. However, the above method has a problem in that it takes a considerable cost according to the modification of the manufacturing equipment.

In addition, to change the structure of the manufacturing machine which is a manufacturing facility as mentioned above generally means attaching a device as a super anode. By applying such a super anode, the size of the nucleus can be changed during the initial nucleation by adjusting the amount of current applied to the super and bone anodes. By adjusting the size of the initial nucleus finely, it is possible to produce a low-light copper foil, there is a problem that can not obtain a low-light copper foil corresponding to the current microcircuit pattern only by this method.

As a second method, a method of obtaining low light copper foil by reducing the concentration of chloride ion in an electrolyte to 1 ppm or less is known. However, in the manufacture of electrolytic copper foil, copper scrap is used as a raw material. For example, lowering the concentration of chlorine ions below 1 ppm is practically possible in the laboratory, and the use of copper scrap in mass production systems still provides an economical way to prevent chlorine ions from the waste wires that make up most of the scrap. It is not being developed until now. Therefore, practicality is rarely limited.

As a third method, a method of obtaining a low roughness copper foil by mechanically polishing an electrolytic copper foil manufactured by buffing is generally known. However, this method requires that a separate production facility be provided and that copper content generated during the buffing process remains. There is a problem that may remain as a remnant when manufacturing a printed circuit board.

As a fourth method, there is a method of controlling the surface morphology of the copper foil by changing the additives added to the electrolyte solution. More specifically, low molecular weight water-soluble cellulose ethers, low molecular weight water-soluble polyalkylene glycol ethers, and low molecular weight water-soluble polyethylene imines It is a method of obtaining low light copper foil by adding an appropriate amount of -soluble polyethyleneimine) and water-soluble sulfonated organic sulfur compound. The above-described method can obtain the desired low-light copper foil by changing only the additives of the electrolyte without changing or modifying the existing milling machine, eliminating the need for mechanical polishing processes such as buffing, and managing extremely low chlorine ions. It can be called a method.

However, in the case of the copper foil manufactured by the above method, the roughness Rz value of the matte side is 3.81 µm, which does not meet the demand of the recent low roughness copper foil.

As a fifth method, a method of manufacturing low-light copper foil using an electrolyte solution containing a small amount of polyethylene glycol, tin ions, iron ions, and chlorine ions of 0.1 ppm or less is known. However, this method, as described above, has a practical limit that is practically impossible to maintain in the concentration of chlorine ion below 0.1 ppm in mass production system.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and the first object of the present invention is that it is unnecessary to change or modify the design of the existing mill in the manufacture of copper foil, and it is possible to add additional mechanical such as mechanical polishing. It is to provide a low-light electrolytic copper foil manufacturing method and an electrolytic copper foil that can produce an electrolytic copper foil having low roughness properties by using an optimal additive system while using the raw materials of the existing low-cost waste wire flow without additional equipment and processes.

A second object of the present invention is to provide a method of manufacturing a low-light electrolytic copper foil and an electrolytic copper foil that can be utilized as an electronic device such as an electrode of a lithium ion battery, a copper foil laminated plate, a printed circuit board, and a flexible circuit board using the same.

Objects of the present invention, the drum 100 of the rotating negative electrode and the positive electrode plate 200 corresponding to the shape having a predetermined gap with respect to the outer periphery of the drum 100 is stored in the electrolyte 600,

The electrolyte 600 includes sulfuric acid, copper ions and chlorine ions,

In the manufacturing method of the electrolytic copper foil 400, the electrolytic copper foil 400 is electrodeposited on the surface of the drum 100 while a current of a corresponding polarity is applied to the drum 100 and the positive electrode plate 200,

The electrolytic solution 600 is prepared by adding 0.1 to 100 ppm gelatin, 0.05 to 50 ppm HEC (Hydroxyethyl Cellulose), and 0.05 to 20 ppm SPS (bis (sodiumsulfopropyl) disulfide) as an additive. Is achieved.

As for the addition amount of the said gelatin, it is more preferable that it is 2-5 ppm.

And it is more preferable that the addition amount of the said HEC is 1-3 ppm.

Moreover, it is more preferable that the addition amount of the said SPS is 0.5-3 ppm.

In addition, the gelatin molecular weight is preferably 10,000 or more.

In addition, it is preferable that a post-treatment process of further forming a nodule on one or both surfaces of the electrolytic copper foil 400 is added.

In addition, the roughness of the matte surface of the electrolytic copper foil 400 is preferably larger than that of the shiny surface.

The objects of the present invention as described above are achieved by a low light electrolytic copper foil, which is produced by the above method.

At this time, the electrolytic copper foil 400 is preferably a nodule further formed on one side or both sides as a post-treatment process.

In addition, it is preferable that the roughness of the matte surface of the electrolytic copper foil 400 is larger than the roughness of the shiny surface.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

1 is a block diagram showing a process of the manufacturing method of the electrolytic copper foil according to the present invention,

Figure 2 is an electron microscope (SEM) photographic photograph of the electrolytic copper foil prepared according to Example 1 of the present invention,

3 is an electron micrograph (SEM) photographing picture of the electrolytic copper foil prepared according to Comparative Example 2 of the present invention.

<Description of the code | symbol about the principal part of drawing>

100: drum 200: positive plate

300: roller 400: electrolytic copper foil

500 tank 600 electrolyte solution

Next, a method of manufacturing a low-light electrolytic copper foil and an electrolytic copper foil according to the present invention will be described with reference to the accompanying drawings.

1 is a block diagram showing a process of the method for producing an electrolytic copper foil according to the present invention.

As shown in FIG. 1, a device for manufacturing an electrolytic copper foil 400 is a structure in which a rotating drum 100 and a positive plate 200 having a round plate shape are spaced apart from each other by a predetermined gap. The drum 100 and the positive electrode plate 200 are stored in a tank 500 containing the electrolyte solution 600.

At this time, the drum 100 has a lower portion relative to the center of rotation, and the positive electrode plate 200 is accommodated in shape corresponding to the stored portion, the drum 100 and the positive electrode plate 200 Are divided into a cathode and an anode, respectively, and a current corresponding to each polarity is applied.

Accordingly, electrolytic processing occurs between the drum 100 and the positive electrode plate 200, and thus the electrolytic copper foil 400 is electrodeposited on the surface of the drum 100. Electrolytic copper foil 400 to be electrodeposited is obtained by the roller 300 of the upper right.

At this time, the basic composition of the electrolyte 600 contained in the tank 500 is sulfuric acid (H ₂ SO ₄ ) of about 50 to 200 g / ℓ, and copper ions (Cu ²⁺ of about 30 to 150 g / ℓ) ) And about 200 mg / l or less of chloride ion (Cl ⁻ ). The temperature of the electrolyte 600 is about 20 to 80 ° C., and the current density is about 20 to 150 A / dm 2.

In addition, in order to control the physical properties of the electrolytic copper foil 400 manufactured by the above method, it is common that an additive is added to the electrolyte solution 600. In the present invention, using the gelatin, HEC (Hydroxyethyl Cellulose), SPS (bis sodium sulfopropyl) disulfide (SPS) as the additive to form a fine circuit pattern and the production of a low-light electrolytic copper foil 400 that can be used for the electrode material of a lithium ion battery Achieved.

In this case, gelatin is a derivative protein, and in the present invention, gelatin having a molecular weight of 12,000 is used, and the dosage is at least about 0.1 ppm to at most about 100 ppm, more preferably in the range of about 1 to 10 ppm. Is preferably added, but it is about 2 to 5 ppm as an optimal embodiment.

If gelatin is added to the electrolytic solution 600 at 0.1 ppm or less, a finer initial structure can be obtained, but the electrolytic copper foil 400 of coarse tissue is obtained by promoting the growth of the electrolytic copper foil 400. The tissue has a high peak height, and thus, it is impossible to obtain the desired low roughness electrolytic copper foil 400.

In addition, when gelatin is added to the electrolyte solution 600 at 100 ppm or more, the coarse growth can be suppressed to obtain an electrolytic copper foil 400 having low roughness, but a high temperature elongation (HTE), which is one of the main characteristics in forming a fine circuit; High Temperature Elongation (measured at 180 ℃) has the disadvantage of remarkably falling.

And the amount of the HEC added as an additive is at least about 0.05 to at most about 50 ppm and more preferably about 0.5 to 5 ppm. Among them, the most optimal embodiment is about 1 to 3 ppm. The HEC, together with the above-mentioned SPS and gelatin, is put into the electrolyte solution 600 and used to perform electrolytic processing, thereby functioning to produce a more stable low-light copper foil by performing interactions that occur alternately with each other (hereinafter referred to as interaction). Can be.

If the HEC is added to the electrolyte 600 at 0.05 ppm or less and used, the electrolytic copper foil 400 having a low interaction ability may be manufactured. In addition, if 50ppm or more is used to function to precipitate copper in the electrolytic copper foil 400, if more than 50ppm HEC is added to the electrolyte 600 to produce the electrolytic copper foil 400, the electrolytic copper foil 400, a copper foil laminated board for a circuit board If manufactured and used to manufacture the printed circuit board provides a cause of failure.

In addition, the input amount of the SPS is added to the electrolyte 600 is preferably at least about 0.05ppm to 20ppm maximum. More preferably, it is about 0.1-10 ppm, and, as an optimal Example, it is good that it is 0.5-3 ppm.

The SPS is a material used as a brightener when plating, and when used, it functions to lower the roughness of the plated tissue through interaction between HEC and gelatin. If the SPS is used in an amount of 0.05 ppm or less, the electrolytic copper foil 400 having a low roughness may be produced due to its low interaction ability, and when used in an amount of 20 ppm or more, it may not function at all. .

Hereinafter, three examples of manufacturing the electrolytic copper foil 400 by varying the amount of the gelatin, HEC, and SPS added to the electrolyte 600 as additives in ppm units will be described.

Example

Electrolytic conditions of the electrolytic copper foil 400 manufactured in the present invention, that is, the basic composition of the electrolyte solution 600 of about 100 g / L sulfuric acid (H ₂ SO ₄ ), about 100 g / L copper ion (Cu ^{2 +} ), 30mg Chlorine ion (Cl ⁻ ) of 1 / L, wherein the temperature of the electrolyte solution 600 was about 60 ° C., and the current density was about 100 A / dm 2.

And the addition amount of the additive added to the electrolyte 600 is shown in Table 1. After the part of the electrolytic copper foil thus prepared is subjected to the post-treatment of a conventional electrolytic copper foil 400 to produce a copper foil laminated plate. It is manufactured to be applicable to a printed circuit board or a flexible circuit board.

The post-treatment of a conventional electrolytic copper foil 400 is a nodule treatment for increasing adhesion to the resin, a barrier treatment for preventing the copper layer from diffusing into the resin layer, an antirust treatment for preventing oxidation of the copper layer, and adhesion to the resin. Silane coupling agent treatment to increase the reliability.

gelatin HEC SPS Example 1 2.5 ppm 3 ppm 1.5 ppm Example 2 3.5 ppm 1 ppm 2.5 ppm Example 3 4.5 ppm 2 ppm 0.5 ppm

The electrolytic copper foil 400 manufactured as described above forms a copper foil laminated plate together with an insulating film layer and an adhesive layer, and the copper foil laminated plate may be etched according to a predetermined circuit design to be manufactured as a circuit board.

Hereinafter, two comparative examples of manufacturing the electrolytic copper foil 400 using the electrolyte 600 based on the existing electrolytic conditions for each of the above embodiments will be presented.

Comparative example

Under the electrolytic conditions of Comparative Example, the basic composition of the electrolyte solution 600 was about 100 g / l of sulfuric acid (H ₂ SO ₄ ), about 100 g / l of copper ions (Cu ²⁺ ), and about 30 mg / l. a ^- a chloride ion (Cl). The temperature of the electrolyte solution 600 thus prepared was about 60 ° C., and the current density was about 100 A / dm 2. The amount of the additive added at this time is shown in Table 2 below.

A portion of the electrolytic copper foil 400 thus prepared was manufactured through a conventional post-treatment described in the embodiment of the electrolytic copper foil 400 to prepare a copper clad laminate and to be applicable to a printed circuit board and a flexible circuit board.

gelatin HEC SPS Thiourea Comparative Example 1 2.5 ppm - 1.5 ppm - Comparative Example 2 3.5 ppm - - 0.4 ppm

2 is an electron micrograph (SEM) photographic view of the electrolytic copper foil prepared according to Example 1 of the present invention, Figure 3 is an electron micrograph (SEM) photographic view of the electrolytic copper foil prepared according to Comparative Example 2 of the present invention.

As shown in FIG. 2 and FIG. 3, the SEM photographs of the embodiments according to the present invention mentioned above and the electrolytic copper foil 400 prepared in the comparative example before the post-treatment process are shown.

Surface roughness of the electrolytic copper foil 400 prepared in Example 1 of Table 1 of the electrolytic copper foil 400 prepared according to the embodiment of the present invention is relatively low and smooth compared to the electrolytic copper foil 400 prepared in Comparative Example 2 of Table 2 On the other hand, the surface of the electrolytic copper foil 400 in Comparative Example 2 can be seen that the relatively high roughness.

In order to quantify this, roughness and tensile strength, elongation, high temperature tensile strength and high temperature elongation were measured and shown in Table 3 as follows.

Roughness Rz (㎛) Tensile strength (kgf / ㎡) Elongation (%) High temperature tensile strength (kgf / ㎡) Elongation at high temperature (%) Example 1 1.8 33.3 15.9 18.3 16.3 Example 2 1.6 34.6 18.1 18.2 15.1 Example 3 2.1 32.8 16.3 19.1 15.3 Comparative Example 1 2.5 34.1 5.8 20.1 8.5 Comparative Example 2 3.5 33.8 8.3 20.3 2.1

In the manufacturing method and the electrolytic copper foil of the low-light electrolytic copper foil according to the present invention as described above, the amount of the additive mentioned in each embodiment is only one embodiment and can be implemented in various other embodiments in the addition range mentioned in the present invention Of course. In addition, it can function to produce an electrolytic copper foil 400, a copper foil laminated plate and a circuit board of various characteristics.

According to the manufacturing method of the low roughness electrolytic copper foil according to the present invention and the electrolytic copper foil and the electronic component using the same according to the present invention, it is possible to manufacture the electrolytic copper foil having a lower surface roughness without changing the structure of the existing manufacturing facilities and equipment, which is required for the auxiliary equipment. There is a feature that can be utilized as a material for circuit boards for fine and high integration and electrode materials of lithium ion batteries without additional cost.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (10)

A drum 100 of a rotating cathode and a cathode plate 200 corresponding to a shape having a predetermined gap with respect to the outer periphery of the drum 100 are stored in the electrolyte 600, The electrolyte 600 includes sulfuric acid, copper ions and chlorine ions, In the manufacturing method of the electrolytic copper foil 400, the electrolytic copper foil 400 is electrodeposited on the surface of the drum 100 while a current of a corresponding polarity is applied to the drum 100 and the positive electrode plate 200, The electrolytic solution 600 is prepared by adding 0.1 to 100 ppm gelatin, 0.05 to 50 ppm HEC (Hydroxyethyl Cellulose), and 0.05 to 20 ppm SPS (bis (sodiumsulfopropyl) disulfide) as an additive. . The method of claim 1, The addition amount of the gelatin is 2 to 5ppm method for producing a low roughness electrolytic copper foil. The method of claim 1, The addition amount of the said HEC is 1-3 ppm, The manufacturing method of the low roughness electrolytic copper foil characterized by the above-mentioned. The method of claim 1, The addition amount of the said SPS is 0.5-3 ppm, The manufacturing method of the low roughness electrolytic copper foil characterized by the above-mentioned. The method according to claim 1 or 2, A method for producing a low light electrolytic copper foil, characterized in that the molecular weight of the gelatin is 10,000 or more. The method according to any one of claims 1 to 4, Method for producing a low-light electrolytic copper foil, characterized in that for adding a post-treatment process to further form a nodule on one surface or both surfaces of the electrolytic copper foil (400). The method according to any one of claims 1 to 4, The roughness of the matte surface of the electrolytic copper foil 400 is larger than the roughness of the shiny surface, the manufacturing method of the low-light electrolytic copper foil. It is manufactured by the method of any one of Claims 1-4, The low light electrolytic copper foil characterized by the above-mentioned. The method of claim 8, The electrolytic copper foil 400 is a low light electrolytic copper foil, characterized in that the nodule is further formed on one side or both sides as a post-treatment process. The method of claim 8, Low roughness electrolytic copper foil, characterized in that the roughness of the matte (matte) surface of the electrolytic copper foil (400) is larger than the roughness of the shiny (shiny) surface.