CN102362559B - Copper foil for printed wiring board and method for producing same - Google Patents

Abstract

The present invention provides a copper foil for a printed wiring board, which is characterized in that at least one surface of the copper foil has a roughened layer, and the roughened layer includes a copper foil having a diameter of 0.1 to 2.0 μm and an aspect ratio of 1.5 or more. Needle-shaped fine copper rough particles; and a method of manufacturing copper foil for printed wiring boards, characterized in that using at least one substance selected from the group consisting of alkyl sulfate salts, tungsten ions, and arsenic ions and containing sulfuric acid An electrolytic bath of copper sulfate is formed on at least one surface of a copper foil with a roughened layer containing needle-shaped fine copper rough particles with a diameter of 0.1 to 2.0 μm and an aspect ratio of 1.5 or more. The subject of this invention is developing the copper foil for semiconductor package boards which can avoid the above-mentioned circuit erosion phenomenon, without deteriorating each other characteristic of copper foil. The subject of this invention is providing the copper foil for printed wiring boards which can improve the roughening process layer of copper foil, and the adhesive strength of copper foil and resin, and its manufacturing method especially.

Description

Copper foil for printed wiring board and manufacturing method thereof

technical field

The present invention relates to copper foil for printed wiring boards excellent in chemical resistance and adhesiveness, and to a method for producing the same. In particular, the present invention provides substrates for packaging represented by BT (bismaleimide-triazine) resin-impregnated substrates that can obtain high peel strength against chemical treatment when forming fine patterns, and can perform fine etching Copper foil and its manufacturing method. Moreover, this invention provides the copper foil for printed wiring boards which can raise peeling strength remarkably in the method of forming a copper pattern by electroless plating after etching the whole surface of copper foil, and its manufacturing method.

Background technique

Copper foil for semiconductor packaging substrates is generally called copper foil for printed wiring boards, and is usually produced through the following steps. First, the copper foil laminate is bonded to a substrate such as synthetic resin under high temperature and pressure. Then, in order to form the target conductive circuit on the substrate, a circuit equivalent to the circuit is printed on the copper foil using a material such as an etch-resistant resin.

And unnecessary part of the exposed copper foil was removed by etching process. After etching, the printed part made of materials such as resin is removed, and a conductive circuit is formed on the substrate. Finally, predetermined components are soldered to the formed conductive circuit, thereby forming various printed circuit boards for electronic devices. Finally, it is bonded to a resist or build-up resin substrate. In general, the quality requirements for copper foil for printed wiring boards are different for the adhesive surface (so-called rough surface) and the non-adhesive surface (so-called glossy surface) that are bonded to the resin substrate. are simultaneously satisfied.

As the requirements for gloss, there are the following requirements: (1) good appearance and no oxidative discoloration during storage, (2) good solder wettability, (3) no oxidative discoloration when heated at high temperature, (4) tightness with the resist film good fit; etc.

On the other hand, for rough surfaces, the main requirements are: (1) no oxidative discoloration during storage, (2) sufficient peel strength from the base material even after high-temperature heating, wet treatment, welding, chemical treatment, etc., (3) ) is laminated with the base material and does not produce so-called laminated stains after etching; etc.

In addition, in recent years, along with the refinement of the pattern, the low profile of the copper foil is required. This requires increased peel strength on the rough side of the copper foil.

In addition, in electronic devices such as personal computers and mobile communications, the high frequency of electrical signals is advancing with the increase in the speed and capacity of communication, and printed wiring boards and copper foils that can cope with this are required. When the frequency of the electrical signal reaches 1 GHz or higher, the influence of the skin effect that the current flows only on the surface of the conductor becomes significant, and the influence of the increase in impedance due to the change of the current transmission route due to the unevenness of the surface cannot be ignored. From this point of view, it is desirable that the surface roughness of the copper foil is small.

In response to such demands, many processing methods have been proposed for copper foil for printed wiring boards.

In general, in the method of treating copper foil for printed wiring boards, using rolled copper foil or electrolytic copper foil, first, in order to improve the adhesive force (peel strength) between the copper foil and the resin, it is usually performed to provide the surface of the copper foil with copper and copper. Roughening of copper oxide particles. Then, in order to have heat-resistant/rust-proof properties, a heat-resistant treatment layer (barrier layer) of brass, zinc, or the like is formed.

Furthermore, in order to prevent surface oxidation or the like during transportation or storage, a product is obtained by subjecting it to antirust treatment such as dipping or electrolytic chromate treatment or electrolytic chromium-zinc treatment.

Among them, the roughening treatment layer plays an important role in improving the adhesive force (peel strength) between the copper foil and the resin. Conventionally, it has been considered that (spherical) protrusions having roundness (丸みのある) are preferable for this roughening treatment. This roundness of protrusions is achieved by suppressing dendrite growth. However, this rounded protrusion peels off during etching, and a phenomenon called "powder fall" occurs. This phenomenon can be said to be natural. This is because the contact area between the spherical protrusion and the copper foil is much smaller than the diameter of the round (spherical) protrusion.

In order to avoid this "powder falling" phenomenon, after the above-mentioned roughening treatment, a thin copper plating layer is formed on the protrusions to prevent peeling of the protrusions (refer to Patent Document 1). This technology has the effect of preventing "powder falling", but there is a problem that the process increases and the effect of preventing "powder falling" differs depending on the thin copper plating.

In addition, a technique of forming a nodular covering layer made of an alloy of copper and nickel on copper foil is known (Patent Document 2). This nodular covering layer is a copper-nickel alloy having a composition different from that of the copper foil as a base material, and has a different etching rate when etching for forming a copper circuit. Therefore, there is a problem that it is not suitable for stable circuit design.

When forming copper foil for printed wiring boards, a heat-resistant/rust-proof treatment layer is usually formed. As an example of the metal or alloy used to form the heat-resistant treatment layer, various copper foils formed with covering layers such as Zn, Cu-Ni, Cu-Co, and Cu-Zn have been put into practical use (for example, refer to Patent Document 3 ).

Among them, copper foil formed with a heat-resistant treatment layer composed of Cu-Zn (brass) is widely used industrially because it has the following excellent characteristics: when laminated on a printed circuit board composed of epoxy resin or the like There is no stain on the resin layer when it is on, and there is little deterioration in peel strength after high temperature heating, etc.

Patent Document 4 and Patent Document 5 describe in detail how to form this heat-resistant treatment layer made of brass.

The copper foil on which the heat-resistant layer made of brass is formed is then etched to form a printed circuit. Recently, hydrochloric acid-based etching solutions are increasingly used in the formation of printed circuits.

However, a printed circuit board using a copper foil having a heat-resistant layer made of brass formed thereon is etched using a hydrochloric acid-based etchant (for example, CuCl ₂ , FeCl _{3 ,} etc.), and copper other than the printed circuit portion is removed. When an unnecessary part of the foil is used to form a conductive circuit, so-called erosion (circuit erosion) of the circuit end (edge) occurs on both sides of the circuit pattern, resulting in a problem that the peel strength from the resin base material deteriorates.

This circuit erosion phenomenon means that the etched side surface exposed from the adhesive boundary layer between the copper foil and the resin base material of the circuit formed by the above-mentioned etching treatment, that is, the heat-resistant/rust-proof treatment layer made of brass, is The above-mentioned etching solution corrodes, and due to insufficient water washing afterwards, the two sides that are usually yellow (because it is made of brass) are corroded and turn red, and the peel strength of this part is significantly deteriorated. Moreover, if this phenomenon occurs over the entire circuit pattern, the circuit pattern is peeled off from the base material, causing a problem.

In view of such a problem, the technology proposed is: roughen the surface of the copper foil, rust preventive treatment of zinc or zinc alloy, and chromate treatment, and adsorb a small amount of chromium ion on the surface after the chromate treatment. Silane coupling agent to improve hydrochloric acid resistance (refer to Patent Document 7).

prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 8-236930

Patent Document 2: Japanese Patent No. 3459964

Patent Document 3: Japanese Patent Publication No. 51-35711

Patent Document 4: Japanese Patent Publication No. 54-6701

Patent Document 5: Japanese Patent No. 3306404

Patent Document 6: Japanese Patent Application No. 2002-170827

Patent Document 7: Japanese Patent Application Laid-Open No. 3-122298

Contents of the invention

The subject of this invention is developing the copper foil for semiconductor package boards which avoids the above-mentioned circuit erosion phenomenon, without deteriorating other various characteristics of copper foil. In particular, an object of the present invention is to provide a copper foil for a printed wiring board capable of improving the roughened layer of the copper foil and improving the adhesive strength between the copper foil and resin, and a method for producing the same.

In order to solve the said subject, this inventor conducted extensive and intensive studies, and as a result, provided the following copper foil for printed wiring boards, and its manufacturing method.

1) A copper foil for a printed wiring board, characterized in that at least one surface of the copper foil has a roughened layer, and the roughened layer includes needles with a diameter of 0.1 to 2.0 μm and an aspect ratio of 1.5 or more. fine copper rough particles.

2) A copper foil for a printed wiring board, characterized in that at least one surface of the copper foil has a roughened layer, and the roughened layer includes needles with a diameter of 0.1 to 2.0 μm and an aspect ratio of 3.0 or more. fine copper rough particles.

3) The copper foil for printed wiring boards according to the above 1) or 2), wherein the number of acicular rough particles is 5 or more in a circuit width of 10 μm.

4) The copper foil for printed wiring boards according to the above 1) or 2), wherein the number of acicular rough particles is 10 or more in a circuit width of 10 μm.

5) The copper foil for printed wiring boards according to any one of the above 1) to 4), characterized in that the roughened layer contains at least one material selected from the group consisting of zinc, nickel, copper, and phosphorus. A heat-resistant/rust-proof layer of an element has a chromate film layer on the heat-resistant/rust-proof layer, and a silane coupling agent layer on the chromate film layer.

6) A method for producing copper foil for printed wiring boards, characterized in that an electrolytic bath containing at least one substance selected from alkyl sulfate salts, tungsten ions, and arsenic ions and containing sulfuric acid/copper sulfate is used. At least one surface of the copper foil is formed with a roughened layer containing needle-shaped fine copper rough particles with a diameter of 0.1 to 2.0 μm and an aspect ratio of 1.5 or more.

7) The method for producing copper foil for printed wiring boards as described in 6) above, wherein a resist containing at least one element selected from zinc, nickel, copper, and phosphorus is formed on the roughened layer. heat/rust-proof layer, then form a chromate film layer on the heat-resistant/rust-proof layer, and then form a silane coupling agent layer on the chromate film layer.

Invention effect

As described above, in the copper foil for printed wiring boards according to the present invention, instead of forming round (spherical) projections for roughening, which were conventionally considered preferable, needles are formed on at least one surface of the copper foil. fine coarse particles. Thereby, there are significant effects that the adhesive strength between the copper foil itself and the resin can be improved, the peel strength can be improved even for the chemical treatment when forming a fine pattern for the substrate for packaging, and fine etching can be performed. Copper foil and its manufacturing method.

In recent years, fine patterning and high frequency of printed circuits have been advanced, and the present invention is used as copper foil for printed circuits (copper foil for semiconductor packaging substrates) and a semiconductor substrate produced by pasting copper foil for semiconductor packaging substrates and resin for semiconductor packaging. The substrate for packaging is extremely effective.

Description of drawings

FIG. 1 is an SEM photograph of the roughened layer of Example 1. FIG.

FIG. 2 is an SEM photograph of the roughened layer of Example 2. FIG.

FIG. 3 is an SEM photograph of the roughened layer of Example 3. FIG.

FIG. 4 is a SEM photograph of Example 4.

FIG. 5 is an SEM photograph of the roughened layer of Example 5. FIG.

FIG. 6 is a SEM photograph of Example 6. FIG.

FIG. 7 is an SEM photograph of the roughened layer of Example 7. FIG.

FIG. 8 is an SEM photograph of the roughened layer of Comparative Example 1. FIG.

FIG. 9 is an SEM photograph of the roughened layer of Comparative Example 2. FIG.

Detailed ways

Hereinafter, in order to facilitate understanding of the present invention, the present invention will be specifically and detailedly described. The copper foil used in the present invention may be either electrolytic copper foil or rolled copper foil.

As described above, in the copper foil for printed wiring boards according to the present invention, instead of forming round (spherical) projections which are conventionally considered preferable for roughening, needles are formed on at least one surface of the copper foil. fine copper rough particles. Its shape is a roughened layer having a diameter of 0.1 to 2.0 μm and a ratio of length (length) to width (diameter) of 1.5 or more.

Furthermore, it is desired to be needle-shaped fine copper rough particles with a diameter of 0.1 to 2.0 μm and an aspect ratio of 3.0 or more, that is, elongate.

The shape of the copper rough particles is approximately the shape of a horsetail (tsukushi), and many of them have protrusions on the upper side as shown in the micrographs described later. The ratio of the smallest diameter to the largest diameter is about 1:1 to about 1:1.2. This ratio is a factor for further improving the adhesive force, and the object of the present invention can be fully achieved if the acicular body has the above-mentioned value.

In addition, among the needle-shaped fine copper rough particles, particles with a deviation diameter of 0.1 to 2.0 μm and a ratio of vertical (length) to lateral (diameter) of 1.5 or more, such as particles with a short length, have different shapes. The situation of the particles is not non-existent, but if the amount is within 5% of the whole, it will not affect the adhesive strength between the copper foil itself and the resin.

When forming a circuit by etching copper foil for a printed wiring board, it is desirable that the number of the copper needle-shaped rough particles is 5 or more in a circuit width of 10 μm. Thereby, the adhesive strength of copper foil and resin can be improved remarkably. In particular, it is desirable that the number of copper acicular rough particles is 10 or more in a circuit width of 10 μm.

The roughened layer containing needle-shaped fine copper rough particles can be produced using an electrolytic bath containing at least one substance selected from alkyl sulfate salts, tungsten ions, and arsenic ions and containing sulfuric acid/copper sulfate.

In order to prevent powder falling and improve peel strength, it is desirable that the roughened layer containing needle-shaped fine copper rough particles is coated with an electrolytic bath containing sulfuric acid/copper sulfate. The specific processing conditions are as follows.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 39.3～118g/L

Cu: 10～30g/L

_H2SO4 : 10～150g _/ L

Na ₂ WO ₄ ·2H ₂ O: 0～90mg/L

W: 0~50mg/L

Sodium lauryl sulfate: 0~50mg

H ₃ AsO ₃ (60% aqueous solution): 0～6315mg/L

As: 0～2000mg/L

(plating condition 1)

Temperature: 30～70℃

(current condition 1)

Current density: 25～110A/ ^dm2

Roughening coulomb volume: 50～500As/dm ²

Plating time: 0.5 to 20 seconds

(liquid composition 2)

CuSO ₄ ·5H ₂ O: 78～314g/L

Cu: 20～80g/L

_H2SO4 : 50 _～ 200g/L

(plating condition 2)

Temperature: 30～70℃

(current condition 2)

Current density: 5～50A/ ^dm2

Roughening coulomb quantity: 50～300As/dm ²

Plating time: 1 to 60 seconds

In addition, a heat-resistant/rust-proof layer containing at least one element selected from zinc, nickel, copper, and phosphorus is further formed on the roughened layer, and a chromate film is further formed on the heat-resistant/rust-proof layer. layer, and a silane coupling agent layer is further formed on the chromate film layer to obtain a copper foil for printed wiring boards.

The heat-resistant/rust-proof layer is not particularly limited, and conventional heat-resistant/rust-proof layers can be used. For example, a brass coating conventionally used for copper foil for semiconductor package substrates can be used.

In addition, a chromate film layer and a silane coupling agent layer are formed on the heat-resistant/rust-proof layer to obtain at least an adhesive surface of the copper foil with the resin. Copper foil laminated with a cover layer composed of these chromate coating layers and silane coupling agent layers is glued to resin, and an etching-resistant printed circuit is formed on the copper foil, and then the printed circuit is removed by etching. The unnecessary part of the copper foil other than the part forms a conductive circuit.

Existing treatments can be used as the heat-resistant/rust-proof layer, and specifically, for example, the following treatments can be used.

(liquid composition)

NaOH: 40～200g/L

NaCN: 70～250g/L

CuCN: 50～200g/L

Zn(CN) ₂ : 2～100g/L

As ₂ O ₃ : 0.01～1g/L

(liquid temperature)

40～90℃

(current condition)

Current density: 1～50A/ ^dm2

Plating time: 1 to 20 seconds

As the chromate coating layer, an electrolytic chromate coating layer or an impregnated chromate coating layer can be used. The amount of Cr in the chromate coating layer is desirably 25 to 150 μg/dm ² .

When the amount of Cr is less than 25 μg/dm ² , there is no antirust layer effect. In addition, when the amount of Cr exceeds 150 μg/dm ² , the effect is saturated and wasteful. Therefore, the amount of Cr is preferably adjusted to 25-150 μg/dm ² .

Examples of conditions for forming the chromate coating layer are listed below. However, as described above, it is not necessary to be limited to these conditions, and any known chromate treatment may be used. This antirust treatment is one of the factors affecting acid resistance, and acid resistance is further improved by chromate treatment.

(a) Dip chromate treatment

K ₂ Cr ₂ O ₇ : 1～5g/L, pH: 2.5～4.5, temperature: 40～60℃, time: 0.5～8 seconds

(b) Electrolytic chromate treatment (chromium-zinc treatment (alkaline bath))

K ₂ Cr ₂ O ₇ : 0.2～20g/L, acid: phosphoric acid, sulfuric acid, organic acid, pH: 1.0～3.5, temperature: 20～40℃, current density: 0.1～5A/dm ² , time: 0.5～8 Second

(c) Electrolytic chromium-zinc treatment (alkaline bath)

K ₂ Cr ₂ O ₇ (Na ₂ Cr ₂ O ₇ or CrO ₃ ): 2~10g/L, NaOH or KOH: 10~50g/L, ZnOH or ZnSO ₄ 7H ₂ O: 0.05~10g/L, pH : 7～13, bath temperature: 20～80℃, current density: 0.05～5A/dm ² , time: 5～30 seconds

(d) Electrolytic chromate treatment (chromium-zinc treatment (acid bath))

K ₂ Cr ₂ O ₇ : 2～10g/L, Zn: 0～0.5g/L, Na ₂ SO ₄ : 5～20g/L, pH: 3.5～5.0, bath temperature: 20～40℃, current density: 0.1～3.0A/dm ² , time: 1～30 seconds

As the silane coupling agent layer used for the copper foil for semiconductor encapsulation board|substrates of this invention, the silane coupling agent normally used for copper foil can be used, and it does not specifically limit. For example, specific conditions for the silane treatment are as follows.

0.2% epoxy silane/0.4% TEOS, PH5

One or more silane coupling agents containing tetraalkoxysilane and alkoxysilane having a functional group having reactivity with resin may be used. Needless to say, the selection of this silane coupling agent layer is also arbitrary, but it is desirable to select in consideration of adhesiveness with resin.

Example

Hereinafter, examples and comparative examples will be described. In addition, since this Example gave a preferable example, this invention is not limited to these Examples. Therefore, all modifications, other embodiments, or forms included in the technical idea of the present invention are included in the present invention.

In addition, comparative examples are provided for comparison with the present invention.

(Example 1)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below was performed on the rough surface (mat surface: M surface) of the copper foil. Processing conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

As addition amount: 1000ppm: use H ₃ AsO ₃ (60% aqueous solution)

(Plating temperature 1) 50°C

(current condition 1)

Current density: 90A/ ^dm2

Roughening coulomb volume: 200As/dm ²

After this roughening treatment, normal plating as shown below is performed. Processing conditions are shown below.

(liquid composition 2)

CuSO ₄ 5H ₂ O: 156g/L

Cu: 40g/L

H ₂ SO ₄ : 100g/L

(Plating temperature 1) 40°C

(current condition 1)

Current density: 30A/ ^dm2

Roughening coulomb volume: 150As/dm ²

The SEM photo of the roughened layer of Example 1 is shown in FIG. 1 . The magnification of the left SEM photograph shown in FIG. 1 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 1 , it can be seen that the particle shape is needle-like. The average particle diameter was 0.57 μm, the particle length was 1.56 μm, and the aspect ratio was 2.7, satisfying the conditions of the present invention.

Then, a heat-resistant/rust-proof layer is formed on the roughened copper surface. As the conditions, a known heat-resistant/rust-proof layer can be used, and this embodiment was carried out under the following conditions.

(liquid composition)

NaOH: 72g/L

NaCN: 112g/L

CuCN: 91.6g/L (Cu: 65g/L)

Zn(CN) ₂ : 8.1g/L (Zn: 4.5g/L)

As ₂ O ₃ : 0.125g/L (As: 95ppm)

(Liquid temperature) 76.5°C

(current condition)

Current density: 6.7A/ ^dm2

Current: 4.0A

Plating time: 5 seconds

Then, an electrolytic chromate treatment is carried out on top of the heat-resistant/rust-resistant layer.

Electrolytic chromate treatment (chromium-zinc treatment (acid bath))

Cr ₂ O ₃ : 0.73g/L

ZnSO ₄ ·7H ₂ O: 2.46g/L

Na ₂ SO ₄ : 18g/L

H ₃ PO ₃ : 0.53g/L

pH: 4.6, bath temperature: 37°C

Current density: 2.06A/ ^dm2

Time: 1~30 seconds

(pH adjustment by sulfuric acid or potassium hydroxide)

Then, silane treatment (by coating) is performed on the chromate film layer.

The conditions for the silane treatment are as follows.

0.2% epoxy silane/0.4% TEOS, PH5

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.79kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 5%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the amount of Loss is as low as 6.6%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 2)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Na ₂ WO ₄ ·2H ₂ O: 5.4mg/L

W addition amount: 3ppm

(Plating temperature 1) 50°C

(current condition 1)

Current density: 40A/ ^dm2

Roughening coulomb volume: 300As/dm ²

The SEM photo of the roughened layer of Example 2 is shown in FIG. 2 . The magnification of the left SEM photograph shown in FIG. 2 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 2 , it can be seen that the particle shape is needle-like. The average particle diameter was 0.67 μm, the particle length was 1.78 μm, and the aspect ratio was 2.7, satisfying the conditions of the present invention.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.83kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 2.3%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the amount of Loss is as low as 4.4%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 3)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Addition of sodium lauryl sulfate: 10ppm

(Plating temperature 1) 50°C

(current condition 1)

Current density: 100A/ ^dm2

Roughening coulomb volume: 200As/dm ²

The SEM photograph of the roughened layer of Example 3 is shown in FIG. 3 . The magnification of the left SEM photograph shown in FIG. 3 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 3 , it can be seen that the needle-like particle shape is maintained although it is slightly close to a spherical shape. The average particle diameter is 0.6 μm, the particle length is 1.5 μm, and the aspect ratio is 2.5, satisfying the conditions of the invention of the present application.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.75kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 7.8%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the Loss content is as low as 8.7%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 4)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Na ₂ WO ₄ ·2H ₂ O: 5.4mg/L

W: 3ppm

As: 150ppm (using H ₃ AsO ₃ (60% aqueous solution))

(Plating temperature 1) 50°C

(current condition 1)

Current density: 90A/ ^dm2

Roughening coulomb volume: 200As/dm ²

The SEM photograph of the roughened layer of Example 4 is shown in FIG. 4 . The magnification of the left SEM photograph shown in FIG. 4 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 4 , it can be seen that the particle shape is needle-like. The average particle diameter was 0.59 μm, the particle length was 1.9 μm, and the aspect ratio was 3.2, satisfying the conditions of the invention of the present application.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.82kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 4.3%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the Loss amount is as low as 6.8%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 5)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Addition of sodium lauryl sulfate: 10ppm

As addition amount: 1000ppm: use H ₃ AsO ₃ (60% aqueous solution)

(plating temperature) 50°C

(current condition)

Current density: 40A/ ^dm2

Coulomb volume of roughening: 240As/dm ²

The SEM photo of the roughened layer of Example 5 is shown in FIG. 5 . The magnification of the left SEM photograph shown in FIG. 5 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 5 , it can be seen that the particle shape is needle-like. The average particle diameter was 0.72 μm, the particle length was 1.93 μm, and the aspect ratio was 2.7, satisfying the conditions of the invention of the present application.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.83kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 4.6%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the amount of Loss is as low as 7.5%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 6)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Na ₂ WO ₄ ·2H ₂ O: 5.4mg/L

W: 3ppm

Addition of sodium lauryl sulfate: 10ppm

(Plating temperature 1) 50°C

(current condition 1)

Current density: 100A/ ^dm2

Roughening coulomb volume: 200As/dm ²

The SEM photo of the roughened layer of Example 6 is shown in FIG. 6 . The magnification of the left SEM photograph shown in FIG. 6 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 6 , it can be seen that the particle shape is needle-like. The average particle diameter was 0.48 μm, the particle length was 1.6 μm, and the aspect ratio was 3.3, satisfying the conditions of the present invention.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.83kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 3.9%, and the amount of loss (Loss) was smaller than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the amount of Loss is as low as 5.2%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(Example 7)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition 1)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

Na ₂ WO ₄ ·2H ₂ O: 5.4mg/L

W: 3ppm

Addition of sodium lauryl sulfate: 10ppm

As addition amount: 150ppm: using H ₃ AsO ₃ (60% aqueous solution)

(Plating temperature 1) 50°C

(current condition 1)

Current density: 80A/ ^dm2

Roughening coulomb volume: 280As/dm ²

The SEM photo of the roughened layer of Example 7 is shown in FIG. 7 . The magnification of the left SEM photograph shown in FIG. 7 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 7 , it can be seen that the particle shape is needle-like. The average particle diameter is 0.55 μm, the particle length is 1.7 μm, and the aspect ratio is 3.1, satisfying the conditions of the invention of the present application.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on top.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.85kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 1.6%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the amount of Loss is as low as 4.5%, and the resistance to sulfuric acid and hydrogen peroxide is good.

(comparative example 1)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below. At this time, the additive of the present invention was not used at all.

(liquid composition)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

(plating temperature) 50°C

(current condition)

Current density: 90A/ ^dm2

Roughening coulomb volume: 200As/dm ²

The SEM photograph of the roughened layer of Comparative Example 1 is shown in FIG. 8 . The magnification of the left SEM photograph shown in FIG. 8 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 8 , it can be seen that the particle shape is dendrite. The average particle diameter is 5 μm, the particle length is 25 μm, and the aspect ratio is 5.0, satisfying the conditions of the invention of the present application.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

In this comparative example 1, dust falling was observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.58kg/cm, which is low. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60° C. for 90 minutes using 12% by weight of hydrochloric acid on a 0.4 mm circuit is expressed in %. Same below. The amount of loss (Loss) was 32.4%, and the amount of loss (Loss) was smaller than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. The results are shown in Table 1.

It can be clearly seen from Table 1 that the Loss amount is as high as 31%, and the resistance to sulfuric acid and hydrogen peroxide is not good.

(comparative example 2)

Using an electrolytic copper foil having a thickness of 12 μm, roughening plating as shown below and normal plating similar to Example 1 were performed on the rough surface (matte surface: M surface) of the copper foil. The roughening plating treatment conditions are shown below.

(liquid composition)

CuSO ₄ ·5H ₂ O: 58.9g/L

Cu: 15g/L

H ₂ SO ₄ : 100g/L

As addition amount: 150ppm: using H ₃ AsO ₃ (60% aqueous solution)

(plating temperature) 50°C

(current condition)

Current density: 40A/ ^dm2

Coulomb volume of roughening: 240As/dm ²

The SEM photograph of the roughened layer of Comparative Example 2 is shown in FIG. 8 . The magnification of the left SEM photograph shown in FIG. 8 is (×3000), and the magnification of the right SEM photograph is (×30000). As shown in FIG. 8 , it can be seen that the particle shape is spherical. The average particle diameter was 1.3 μm, the particle length was 1.8 μm, and the aspect ratio was 1.4, which did not satisfy the conditions of the present invention.

Then, on the roughened surface of the above-mentioned copper, form the same heat-resistant/rust-proof layer as in Example 1, carry out electrolytic chromate treatment on the heat-resistant/rust-proof layer, and then coat the chromate film layer Silane treatment (by coating) is carried out on the surface.

The copper foil laminate produced in this way was bonded to a glass cloth substrate BT (bismaleimide-triazine) resin plate, and the following items were measured or analyzed.

(1) Observation of falling powder

Powder falling was not observed. The results are shown in Table 1.

(2) normal peel strength

The normal peel strength is 0.82kg/cm, which has good peel strength. The results are shown in Table 1.

(3) Hydrochloric acid resistance test

For hydrochloric acid resistance, the amount of loss (Loss) after immersion at 60 degreeC for 90 minutes was shown by % using 12 weight% hydrochloric acid. Same below. The amount of loss (Loss) was 20%, and the amount of loss (Loss) was less than that of the comparative example described later, showing favorable properties. The results are shown in Table 1.

(4) Test results of resistance to sulfuric acid and hydrogen peroxide (10% sulfuric acid, 2% hydrogen peroxide, room temperature: 30°C)

Implemented on a 0.4mm circuit. At this time, the case of etching 2 μm was examined. The amount of loss (Loss) is expressed in %. Same below. The results are shown in Table 1.

It can be clearly seen from Table 1 that the Loss amount is as high as 15%, and the resistance to sulfuric acid and hydrogen peroxide is not good.

From the above, it can be seen that in the copper foil for printed wiring boards of the present invention, roundness (spherical) protrusions or dendritic crystal grain diameters, which were conventionally considered good for roughening treatment, are not formed. Instead, needle-shaped fine rough particles are formed on at least one surface of the copper foil, thereby having the following remarkable effect: it is possible to improve the adhesive strength between the copper foil itself and the resin. For the packaging substrate, even for Chemical treatment when forming a fine pattern can also improve the peel strength, and finely etched copper foil and its manufacturing method can be performed.

Industrial applicability

As described above, the present invention forms needle-shaped fine rough particles on at least one surface of the copper foil, thereby having the following remarkable effects: it is possible to provide a resin that can improve the adhesive strength between the copper foil itself and the resin, and is suitable for packaging substrates. In other words, a copper foil that can improve peel strength even for chemical treatment when forming a fine pattern, and can perform fine etching, and a manufacturing method thereof.

In recent years, fine patterning and high frequency of printed circuits have been promoted, and the present invention is used as copper foil for printed circuits (copper foil for semiconductor packaging substrates) and a semiconductor package produced by pasting copper foil for semiconductor packaging substrates and resin for semiconductor packaging. The substrate for packaging is extremely effective.

Claims (9)

1. a printed wiring board-use copper-clad, is characterized in that, at least one face of Copper Foil, has roughening processing layer, and it is that 0.1～2.0 μ m and aspect ratio are the fine copper coarse particles of more than 1.5 needle-like that described roughening processing layer comprises diameter.

2. a printed wiring board-use copper-clad, is characterized in that, at least one face of Copper Foil, has roughening processing layer, and it is that 0.1～2.0 μ m and aspect ratio are the fine copper coarse particles of more than 3.0 needle-like that described roughening processing layer comprises diameter.

3. printed wiring board-use copper-clad as claimed in claim 1 or 2, is characterized in that, the quantity of needle-like coarse particles for to exist more than 5 in the circuit width of 10 μ m.

4. printed wiring board-use copper-clad as claimed in claim 1 or 2, is characterized in that, the quantity of needle-like coarse particles for to exist more than 10 in the circuit width of 10 μ m.

5. printed wiring board-use copper-clad as claimed in claim 1 or 2, it is characterized in that, on described roughening processing layer, have contain be selected from zinc, nickel, copper, phosphorus at least one above element heat-resisting/antirust coat, on this heat-resisting/antirust coat, there is chromate by rete, and there is silane coupling agent layer at this chromate on by rete.

6. printed wiring board-use copper-clad as claimed in claim 3, it is characterized in that, on described roughening processing layer, have contain be selected from zinc, nickel, copper, phosphorus at least one above element heat-resisting/antirust coat, on this heat-resisting/antirust coat, there is chromate by rete, and there is silane coupling agent layer at this chromate on by rete.

7. printed wiring board-use copper-clad as claimed in claim 4, it is characterized in that, on described roughening processing layer, have contain be selected from zinc, nickel, copper, phosphorus at least one above element heat-resisting/antirust coat, on this heat-resisting/antirust coat, there is chromate by rete, and there is silane coupling agent layer at this chromate on by rete.

8. the manufacture method of a printed wiring board-use copper-clad, it is characterized in that, use contains and is selected from least one above material of alkyl sodium sulfate ester salt, tungsten ion, arsenic ion and the electrobath that comprises sulfuric acid/copper sulphate, on at least one face of Copper Foil, form roughening processing layer, it is that 0.1～2.0 μ m and aspect ratio are the fine copper coarse particles of more than 1.5 needle-like that described roughening processing layer comprises diameter.

9. the manufacture method of printed wiring board-use copper-clad as claimed in claim 8, it is characterized in that, on described roughening processing layer, form contain be selected from zinc, nickel, copper, phosphorus at least one above element heat-resisting/antirust coat, then on this heat-resisting/antirust coat, form chromate by rete, then form silane coupling agent layer at this chromate on by rete.