JP6880810B2 - A surface treatment method for a resin film and a method for manufacturing a copper-clad laminated substrate having the same. - Google Patents

Description

The present invention relates to a method for surface-treating a resin film and a method for producing a copper-clad laminated substrate having the surface-treating method.

Electronic devices such as liquid crystal panels, notebook computers, digital cameras, and mobile phones use flexible wiring substrates in which wiring circuits are formed on one or both sides of a heat-resistant resin film. This flexible wiring substrate can be produced by patterning the metal film of a resin film with a metal film obtained by coating one side or both sides of the heat-resistant resin film with a metal film.

Conventionally, as a method for producing a resin film with a metal film, a metal foil is attached to a resin film with an adhesive (a method for producing a three-layer substrate), a metal foil is coated with a resin solution, and then dried. (Casting method), and a method of forming a metal film on a resin film by the vacuum film formation method alone or in combination with the vacuum film formation method and the wet plating method (metalizing method). Are known. Further, as the vacuum film forming method adopted in the metallizing method, a vacuum vapor deposition method, a sputtering method, an ion plating method, an ion beam sputtering method and the like are known.

For example, Patent Document 1 discloses, as a metallizing method, a method in which a chromium layer is sputter-deposited on a polyimide substrate and then a copper layer is sputter-deposited to form a conductor layer having a laminated structure on an insulating layer. ing. Further, in Patent Document 2, a first metal thin film formed by a sputter film formation targeting a copper-nickel alloy and a second metal thin film formed by a sputter film formation targeting copper are formed on the polyimide film in this order. A copper-clad laminated substrate of a two-layer substrate laminated in the above is disclosed. In order to continuously perform vacuum film formation on a long resin film, a sputtering web coater capable of performing a dry plating treatment on the surface of the long resin film (web) while transporting it in a roll-to-roll manner. Is generally used.

By the way, among the above vacuum film forming methods, the resin film with a metal film obtained by the sputtering method generally has excellent adhesion between the resin film and the metal film, but is a resin film on which the metal film is actually formed. When the peel strength was measured, it was often peeled off inside the resin film by so-called cohesive peeling without peeling at the interface between the metal film and the resin film. It is considered that the cohesive peeling occurs in this way because a layer with low strength called a fragile layer is generally present on the surface layer of the resin film, and the peeling occurs from that layer.

Therefore, in the vacuum film forming method, it has been proposed to improve the peel strength by subjecting the resin film to plasma treatment or ion beam treatment as a pretreatment. For example, Patent Document 3 defines the effect of adhesion by the thickness of the modified layer on the surface of the polyimide film modified by plasma treatment in a two-layer copper polyimide substrate composed of a polyimide film, a metal seed layer and a copper layer. The technology is disclosed. Further, Patent Document 4 discloses a technique for defining the effect of adhesion by the thickness of the metal mixed layer in a metal film polyimide resin substrate on which a barrier layer, a seed layer, and a conductive layer are formed after modification by a dry method. Has been done.

Japanese Unexamined Patent Publication No. 2-98994 Japanese Patent No. 3447070 Japanese Unexamined Patent Publication No. 2007-318177 International Publication No. 2010/098236

The surface treatment of the resin film by the above-mentioned plasma treatment or ion beam treatment effectively removes the fragile layer near the surface of the resin film and improves the adhesion by generating a functional group that exhibits adhesion. I am trying. However, the thickness of the fragile layer can vary depending on the type and thickness of the resin film and the manufacturing method of the resin film. Therefore, in order to improve the peel strength, for example, the processing conditions of plasma treatment are adjusted according to the type and thickness of the resin film. It was necessary to adjust the irradiation conditions of the ion beam, and it was sometimes necessary to drastically change the conditions such as the processing speed in order to optimize the conditions.

The present invention has been made by paying attention to such a conventional problem, and by efficiently removing a fragile layer in which the thickness and the like may vary due to different types of resin films and manufacturing methods, the resin is used. It is an object of the present invention to provide a surface treatment method for a resin film capable of reducing the variation in adhesion to a metal film formed on a film, and a method for manufacturing a copper-clad laminated substrate using the surface treatment method. ..

In order to achieve the above object, the present inventors wind a long resin film conveyed by roll-to-roll around the outer peripheral portion of a can roll and cool it while forming a metal film on the long resin film by sputtering. In this case, by bringing the surface of the long resin film into contact with a metal roller having an active surface state that is not oxidized before the film formation, the fragile layer of the long resin film is peeled off into a metal roller. We have found that it can be attached, and have completed the present invention.

That is, the surface treatment method for the resin film of the present invention is a surface treatment in which at least one surface of a long resin film transported in a roll-to-roll manner under a reduced pressure atmosphere is rotated following the transport of the long resin film. A surface that peels off the fragile layer of the long resin film and adheres to the non-oxidized active metal surface before forming the metal film by contacting the roll with the non-oxidized active metal surface. In the treatment method, the unoxidized active metal surface has come to a position where the region of the outer peripheral surface of the surface treatment roll that comes into contact with the long resin film does not come into contact with the long resin film due to the rotation. It is characterized in that it is sometimes formed by sputtering means.

According to the present invention, since the fragile layer of the resin film can be removed, the adhesion between the resin film and the metal film formed on the surface of the resin film can be enhanced.

It is a schematic cross-sectional view of the copper-clad laminated substrate which can be produced by the manufacturing method of the copper-clad laminated substrate of this invention. It is a schematic front view of the surface treatment film forming apparatus which can carry out the surface treatment method of the resin film of this invention. FIG. 5 is a schematic front view of a roll-to-roll continuous electroplating apparatus preferably used when wet plating is performed after dry plating in the surface treatment film forming apparatus of FIG. 2.

Hereinafter, a specific example of the surface treatment method for the resin film according to the present invention will be described with reference to a case where a copper-clad laminated substrate for a flexible wiring board of a two-layer substrate is manufactured by a metallizing method. As shown in FIG. 1, in a copper-clad laminated substrate, generally, a base metal layer 2 and a copper layer 3 are sequentially formed on at least one surface of a resin film 1 represented by a polyimide film without using an adhesive. It has a laminated structure that is laminated on. The copper layer 3 may be composed of one layer, but in FIG. 1, it has a laminated structure of a copper thin film layer 3a and a copper electroplating layer 3b.

The material of the resin film 1 is not limited to the polyimide film, and a polyamide film, a polyester film, a polytetrafluoroethylene film, a polyphenylene sulfide film, a polyethylene naphthalate film, a liquid crystal polymer film and the like can be used. Among these materials, a polyimide film is preferable from the viewpoint of mechanical strength, heat resistance and electrical insulation.

The base metal layer 2 plays a role of improving the adhesion and heat resistance between the resin film 1 and the copper layer 3 and ensuring the reliability of the copper-clad laminated substrate, and the material thereof is nickel, chromium, or these. Of these, an alloy composed of at least one of the above is preferable, and a nickel-chromium alloy is particularly preferable from the viewpoint of adhesion strength and ease of etching during patterning processing of a wiring circuit. The composition of the nickel-chromium alloy is preferably 15% by mass or more and 22% by mass or less of chromium from the viewpoint of improving corrosion resistance and migration resistance. Of these, a nickel-chromium alloy (Ni-20Cr) having 20% by mass of chromium is distributed as a nichrome alloy and can be easily obtained as a sputtering target by the magnetron sputtering method. Further, a base metal layer having a concentration gradient in the thickness direction may be formed by laminating a plurality of nickel-chromium alloy thin films having different chromium concentrations. In the case of an alloy containing nickel, chromium, vanadium, titanium, molybdenum, cobalt and the like may be added.

The thickness of the resin film 1 is preferably 12.5 μm or more and 75 μm or less. The film thickness of the base metal layer 2 is preferably 3 nm or more and 50 nm or less. If the film thickness of the base metal layer 2 is less than 3 nm, it becomes difficult to stably maintain the adhesiveness with the copper layer 3 especially when the resin film 1 is a polyimide film, and the corrosion resistance and migration resistance become insufficient. There is a risk. On the other hand, if the film thickness of the base metal layer 2 exceeds 50 nm, it becomes difficult to sufficiently remove the base metal layer 2 when processing the wiring circuit by the subtractive method, and problems such as migration between adjacent wirings occur. There is a risk. The thickness of the copper layer 3 is preferably 100 nm or more and 20 μm or less, and the upper limit thereof is more preferably 12 μm or less. When the copper layer 3 has a two-layer structure as shown in FIG. 1, it is preferable that the film thickness of the copper thin film layer 3a is 10 nm or more and 1 μm or less, and the remaining film thickness is due to the copper electroplating layer 3b.

Next, the above-mentioned method for manufacturing a copper-clad laminated substrate will be described by taking as an example a case where a resin film is surface-treated and then a film formation by dry plating and a film formation by wet plating are performed in this order. .. First, the surface treatment film forming apparatus 10 shown in FIG. 2 will be described. In this surface treatment film forming apparatus 10, after pretreatment is applied to the surface of a long resin film F conveyed by roll-to-roll, the surface to which the pretreatment is applied is subsequently subjected to film formation by dry plating. Is.

Specifically, the surface treatment film forming apparatus 10 includes various roll groups that define a transport path of the long resin film F that is transported by roll-to-roll, and before the long resin film F is pretreated. It is mainly composed of a processing means and a film forming means for performing a film forming process on the long resin film F after the pretreatment, and these are various vacuum devices such as a dry pump, a turbo molecular pump, and a cryocoil (not shown). It is housed in the housing 11 provided with the above. The shape of the housing 11 is not limited to the rectangular parallelepiped shape shown in FIG. 2 as long as it can withstand a reduced internal atmosphere of about ^{10 -4 to 1 Pa, and may be a cylindrical shape or the like.}

The various roll groups include an unwinding roll 12 from which the long resin film F is unwound, and a surface treatment roll as a first pretreatment means for performing a first surface treatment on the unwound long resin film F. 14. The nip roll 15 that sandwiches the long resin film F with the outer peripheral surface of the surface treatment roll 14, and the long resin film F after the first pretreatment is further heat-loaded by the second pretreatment means. The first canroll 18 is cooled when the second pretreatment is applied, and the long resin film F after the two pretreatments is cooled when a heat-loaded sputtering film is formed. The second can roll 21, the front feed roll 20a and the rear feed roll 20b located immediately upstream and downstream of the second can roll 21, respectively, and the winding for winding the long resin film F formed by sputtering. It is composed of a take-up roll 23 and guide rolls 13a to 13n appropriately provided between these rolls. The inside of the housing 11 is divided into five spaces by a partition wall: an unwinding zone, a first pretreatment zone, a second pretreatment zone, a sputtering film formation zone, and a winding zone. The above roll groups are arranged in the space.

The surface treatment sputtering cathode 16 is provided at a position facing the outer peripheral surface located in the angle range that does not come into contact with the long resin film F in the entire angle range centered on the rotation axis of the surface treatment roll 14. There is. By the surface treatment sputtering cathode 16, an unoxidized active metal film (hereinafter, also referred to as an unoxidized active metal film) can be formed on the outer peripheral surface of the surface treatment roll 14. That is, the region of the outer peripheral surface of the surface treatment roll 14 that comes into contact with the long resin film F is formed with an unoxidized active metal surface by sputtering when it comes to a position where it does not come into contact with the long resin film F due to rotation. It has become like. The metal used as the material of the non-oxidized active metal film is preferably copper, nickel, chromium, titanium, or an alloy thereof. In particular, nickel, chromium, or titanium is desirable because organic substances are easily bonded by coordination or the like.

The thickness of the non-oxidized active metal film formed on the outer peripheral surface of the surface treatment roll 14 by the above-mentioned sputtering cathode 16 for surface treatment is preferably 1 nm or more and 10 nm or less. If the thickness of the metal film is less than 1 nm, it is too thin and it becomes difficult to form the non-oxidized active metal film substantially uniformly. On the other hand, even if the thickness of this metal film exceeds 10 nm, the effect is hardly improved. The thickness of the non-oxidized active metal film can be estimated from the film formation efficiency of the sputtering cathode 16. The film formation efficiency of the sputtering cathode 16 can be known by forming a non-oxidizing active metal film on a resin film using the sputtering cathode 16 and measuring the thickness of the non-oxidizing active metal film formed on the resin film. it can. From the film formation efficiency of the sputtering cathode 16, the thickness of the unoxidized active metal film may be controlled by the power input to the sputtering cathode 16.

Of the entire angle range centered on the rotation axis of the surface treatment roll 14, the position facing the outer peripheral surface located within the angle range that does not come into contact with the long resin film F is the surface treatment sputtering cathode 16. In addition, it is desirable to provide a processing means for cleaning the outer peripheral surface. In the surface treatment film forming apparatus 10 of FIG. 2, the cleaning treatment means 17 for cleaning the outer peripheral surface of the surface treatment roll 14 is located at a position facing the outer peripheral surface and is described above with respect to the rotation direction of the surface treatment roll 14. It is provided on the front side of the surface treatment sputtering cathode 16. As a result, the region of the outer peripheral surface of the surface treatment roll 14 that comes into contact with the long resin film F is the position where the long resin film F comes into contact with the rotation, and the active metal that has not been oxidized by the above-mentioned surface treatment sputtering cathode 16. A cleaning process is applied when it comes between the position where the surface is formed.

By providing the above-mentioned cleaning treatment means 17, the fragile layer from the long resin film F transferred to the surface of the non-oxidized active metal film on the outer peripheral surface of the surface treatment roll 14 can be removed. That is, the outer peripheral surface of the surface treatment roll 14 is fragile from the surface treatment roll 14 due to (1) film formation of an unoxidized active metal film by sputtering and (2) contact with a long resin film F due to its rotation. The surface treatment cycle consisting of layer transfer and (3) removal of the fragile layer by a cleaning treatment is repeated.

The cleaning processing means 17 is preferably performed by plasma irradiation or ion beam irradiation. The output of plasma irradiation or ion beam irradiation may be any output that can satisfactorily remove the fragile layer from the long resin film F transferred to the surface of the non-oxidized active metal film on the outer peripheral surface of the surface treatment roll 14. The surface treatment film forming apparatus 10 shown in FIG. 2 shows a case where a cleaning ion source for irradiating an ion beam is provided as the cleaning treatment means 17.

If the atmosphere of this cleaning treatment and the sputtering film formation treatment on the long resin film F described later can be shared, ion beam treatment or plasma treatment using argon gas is preferable, and in terms of controlling the gas pressure. Ion beams are more preferred. On the other hand, in the case of equipment that can independently control the atmosphere of the sputtering film forming process and the cleaning process on the long resin film F, the cleaning process involves argon having a gas pressure different from that of the sputtering film forming process. It is preferable to use plasma in a gas atmosphere, an atmosphere mainly containing oxygen gas or nitrogen gas, an atmosphere containing a part of argon gas, or a mixed gas atmosphere thereof. Of these, plasma in an atmosphere containing oxygen gas as the main component is most suitable for removing the fragile layer. The gas pressure of the atmospheric gas is preferably 0.6 to 2.5 Pa, and the applied voltage of the plasma is preferably 800 to 2600 V.

It is desirable that the long resin film F in contact with the outer peripheral surface of the surface treatment roll 14 is sandwiched between the long resin film F and the outer peripheral surface of the surface treatment roll 14 by using the nip roll 15 as described above. By sandwiching the long resin film F between the surface treatment roll 14 and the nip roll 15 in this way, one side of the long resin film F can be reliably brought into contact with the surface of the unoxidized active metal film of the surface treatment roll 14. it can. The pressure when the long resin film F is sandwiched between the nip roll 15 and the surface treatment roll 14 is preferably 30 N or more and 180 N or less, more preferably 30 N or more and 150 N or less, and further preferably 30 N or more and 120 N or less. If this pressure is less than 30 N, the long resin film F may not surely come into contact with the surface treatment roll 14. On the contrary, if it exceeds 180 N, it becomes difficult to control the transport tension of the long resin film F.

Instead of the nip roll 15, the transport tension of the long resin film F may be adjusted to a predetermined value, and the long resin film F may be partially wound around the outer peripheral surface of the surface treatment roll 14. In this case, the long resin film F is surely applied to the surface of the unoxidized active metal film of the surface treatment roll 14 by the drag force of the following formula 1 generated between the long resin film F and the outer peripheral surface of the surface treatment roll 14. It can be brought into contact with each other, and the surface treatment of the long resin film F can be stably performed as in the case of the nip roll 15.
[Equation 1]
Drag = Conveying tension of long resin film / (radius of surface treatment roll x width of long resin film)

Also in this case, the transport tension of the long resin film F and the radius of the surface treatment roll 14 are appropriately selected so that the drag force generated between the long resin film F and the outer peripheral surface of the surface treatment roll 14 is 30 to 180 N. do it. However, since the drag force received by the long resin film F from the outer peripheral surface of the surface treatment roll 14 changes according to the angular position in the circumferential direction, the transport tension of the long resin film F and the long resin film on the surface treatment roll 14 It is preferable to appropriately adjust the holding angle of F (that is, the angle range around which the long resin film F is wound out of the entire outer peripheral surface of the surface treatment roll 14). Further, if the thickness of the long resin film F becomes thin, wrinkles (trough wrinkles) may occur or break due to an increase in tension. Therefore, the long resin film F is applied to the outer peripheral surface of the surface treatment roll 14. In addition to wrapping and adjusting the drag force, it is preferable to use the above-mentioned nip roll 15 together.

It is desirable that the long resin film F from which the fragile layer has been removed by contact with the unoxidized active metal is further surface-treated by plasma treatment, ion beam treatment, or the like. When the surface of the long resin film F from which the fragile layer has been removed is irradiated with plasma or an ion beam, a functional group such as a carboxyl group can be introduced into the molecules constituting the long resin film F, so that the long resin can be used. The adhesion between the film F and the underlying metal layer formed on the surface thereof can be further improved.

However, when the long resin film F is subjected to plasma treatment or ion beam treatment, the temperature of the long resin film F rises, so that the temperature needs to be adjusted. In the surface treatment film forming apparatus 10, the entire angle range centered on the rotation axis of the first can roll 18 is processed so that the long resin film F is ion beamed when it is wound around the outer peripheral surface of the first can roll 18. Of these, for surface treatment for irradiating an ion beam toward the surface of the long resin film F on the outer peripheral surface at a position facing the outer peripheral surface located within the angle range around which the long resin film F is wound. An ion source 19 is provided. Then, the refrigerant supplied from the outside of the housing 11 circulates in the flow path provided inside the first can roll 18.

It is desirable that the long resin film F that has been subjected to the first and second surface treatments as described above is subsequently subjected to the film formation treatment of the base metal and the copper thin film layer by the dry plating method in the same apparatus. By continuously performing surface treatment and film formation treatment on the long resin film F in the same apparatus, a base metal layer is formed on the surface of the long resin film F with almost no contamination. This is because a film can be formed. Examples of the dry plating method for forming the underlying metal layer and the copper thin film layer on the long resin film F include a sputtering method, an ion plating method, a cluster ion beam method, a vacuum deposition method, and a CVD method. The sputtering method is desirable from the viewpoint of controlling the composition of the underlying metal layer as the seed layer.

When a film is formed on the long resin film F by a sputtering method, a known sputtering film forming means can be used, and for example, a general roll-to-roll sputtering device (sputtering web coater) can be used. By using a roll-to-roll sputtering device, a polyimide film with a copper thin film layer can be produced by continuously and efficiently forming a base metal layer and a copper thin film layer on the surface of a long resin film made of a polyimide film or the like. it can.

The surface treatment film forming apparatus 10 of FIG. 2 is a roll-to-roll sputtering apparatus so that such continuous sputtering film formation is possible. That is, the second can roll 21 transfers the long resin film F, which is transported from the unwinding roll 12 to the winding roll 23 in the housing 11 by roll-to-roll along the transport path defined by the various roll groups described above. While being wound around the outer peripheral surface of the above and cooled, the sputtering film formation is performed by the sputtering film forming means described later.

Among the above roll groups, the second can roll 21, the front feed roll 20a located immediately upstream of the second can roll 21, the unwinding roll 12 and the winding roll 23 are provided with a power source by a servomotor. The other rolls are free rolls. Further, in the unwinding roll 12 and the winding roll 23, the tension balance of the long resin film F is maintained by torque control by a powder clutch or the like. The guide rolls 13j and 13k are provided with a tension sensor for measuring the tension of the long resin film F to be conveyed.

The outer peripheral surface of the second can roll 21 is finished with hard chrome plating, and a refrigerant circulation path as a cooling mechanism is provided inside the second can roll 21. The outer peripheral surface of the second canroll 21 can be adjusted to a constant temperature by circulating a refrigerant or a hot medium supplied from the outside of the housing 11 through the refrigerant circulation path. With the above configuration, the long resin film F can be reliably brought into close contact with the outer peripheral surface of the second can roll 21, so that the long resin film F is subjected to a sputtering film formation with a heat load by a film forming means described later. However, wrinkles and the like are hardly generated on the long resin film F.

At positions facing the outer peripheral surface of the second canroll 21, for example, sputtering cathodes 22a, 22b, 22c, and 22d of the magnetron cathode method as a sputtering film forming means are arranged in this order along the transport path of the long resin film F. The long resin film F is provided so that the surface of the long resin film F can be subjected to a sputtering film forming process, which is a dry film forming process in which a heat load is applied. In the sputtering cathodes 22a to 22d, the length extending in the width direction of the long resin film F is preferably wider than the width of the long resin film F.

When the surface of the long resin film F is pretreated using the above surface treatment film forming apparatus 10 and then the underlying metal layer and the copper thin film layer are formed, a target having the composition of the underlying metal layer is, for example, a sputtering cathode. A copper target is attached to the remaining sputtering cathodes 22b to 22d while being attached to 22a. Further, as the long resin film F, for example, a long polyimide film is set on the unwinding roll 12, and the refrigerant is circulated through the first and second can rolls 18 and 21. Then, after the inside of the housing 11 is evacuated, a sputtering gas such as argon is introduced to maintain the atmospheric pressure at about 1.3 Pa. In this state, power is supplied to the above-mentioned surface treatment sputtering cathode 16, cleaning processing means 17, and sputtering cathodes 22a to 22d while conveying a long polyimide film in a roll-to-roll manner. As a result, the polyimide film F2 with a copper thin film layer having excellent adhesion can be produced. The copper thin film layer may be formed by a vapor deposition method after the underlying metal layer is formed by sputtering.

Next, a copper electroplating layer is formed on the polyimide film F2 with a copper thin film layer on which the base metal layer and the copper thin film layer are formed by the surface treatment film forming apparatus 10 by an electroplating method. The film thickness of the copper electroplating layer to be formed is preferably 1 μm or more and 20 μm or less. As this electroplating method, for example, a method of performing electroplating using an insoluble anode in a copper plating bath containing copper sulfate can be used. The composition of this copper plating bath is not particularly limited, and a commonly used high-slow copper sulfate plating bath for printed wiring boards can be used.

FIG. 3 shows a roll-to-roll continuous electroplating apparatus (hereinafter, also referred to as a plating apparatus 30) as a specific example of a plating apparatus capable of forming a copper plating film by the above electroplating method. In this plating apparatus 30, copper having a predetermined film thickness is obtained by repeatedly immersing the polyimide film F2 with a copper thin film layer continuously unwound from the unwinding roll 32 into the plating solution in the electroplating tank 31. The electroplating layer is formed by electroplating. After electroplating, it is wound around a winding roll 36 as a copper-clad laminated substrate S, which is a metallized resin film substrate for a two-layer flexible wiring board.

More specifically, the polyimide film F2 with a copper thin film layer unwound from the unwinding roll 32 at a transport speed preferably in the range of several m to several tens of m / min is moved downward by the feeding roll 33a. After being changed, it is guided into the plating solution stored in the electroplating tank 31. The polyimide film F2 with a copper thin film layer that runs downward in the plating solution runs upward in the plating solution after the traveling direction is reversed by the reversing roll 35a, and is pulled up above the liquid level of the plating solution by the feeding roll 33b. Be done.

Insoluble anodes 34a and 34b are provided at positions facing the polyimide film F2 traveling downward and the polyimide film F2 traveling upward, respectively. A power supply (not shown) is connected between the power feeding roll 33a and the insoluble anodes 34a and 34b, and electricity is supplied by the power feeding roll 33a, the insoluble anodes 34a and 34b, the plating solution, the polyimide film F2 with the copper thin film layer, and the power supply. The plating circuit is configured.

With the above configuration, the plating layer is formed on the surface of the copper thin film only while it is immersed in the plating solution. Therefore, by repeating the immersion in the plating solution a predetermined number of times (4 times in FIG. 3), the plating layer is formed. A copper electroplating layer having a desired film thickness can be formed on the metal thin film of the polyimide film F2 with a copper thin film layer. This makes it possible to manufacture a copper-clad laminated substrate S for a two-layer flexible wiring board. As the insoluble anode, a known anode whose surface is coated with a conductive ceramic can be used. Further, the outside of the electroplating tank 31 is provided with a mechanism for supplying copper ions to the plating solution. A copper oxide aqueous solution, a copper hydroxide aqueous solution, a copper carbonate aqueous solution, or the like may be used to supply copper ions to the plating solution, or a small amount of iron ions are added to the plating solution to dissolve oxygen-free copper balls. It may be a method.

[Example 1]
Using the surface treatment film forming apparatus 10 as shown in FIG. 2, a surface treatment was applied to Kapton 150 ENC (film width 500 mm) having a thickness of 38 μm made of polyimide made by Toray Dupont as a long resin film F, and then surface-treated. A sputtering film was formed. For this surface treatment, a Cu—Ni alloy having a film thickness of 10 Å (1 nm) was formed on the outer peripheral surface of the surface treatment roll 14 having a radius of 20 cm by the surface treatment sputtering cathode 16.

The cleaning treatment of the outer peripheral surface of the surface treatment roll 14 was performed by irradiating the cleaning treatment means 17 with an argon ion beam having a flow rate of 100 sccm and 2000 V. As a result, the outer peripheral surface of the surface treatment roll 14 is subjected to (1) film formation of an unoxidized and active metal film, (2) contact with the long resin film F, and (3) cleaning treatment by its rotation. The surface treatment cycle consisting of Since the transport tension of the long resin film F was set to 100 N on the upstream side and the downstream side of the surface treatment roll 14, the drag force generated between the long resin film F and the surface treatment roll 14 was 1000 N.

After the above surface treatment, a Ni-20Cr alloy having a film thickness of 5 nm was formed by sputtering without treatment with the surface treatment ion source 19, and a copper thin film layer having a film thickness of 100 nm was formed by sputtering on the surface thereof. With respect to the film-forming surface of the long resin film F thus formed by dry plating, the thickness of the copper layer was set to 8 μm by using the roll-to-roll continuous electroplating apparatus 30 as shown in FIG. Copper was electroplated with an aqueous solution of copper sulfate having a pH of 1. As a result, a copper-clad laminated substrate was produced.

Further, as the long resin film F, a polypropylene film having a thickness of 10 μm made by Shinetsu Film, a Shine SRF having a thickness of 80 μm made of PET made by Toyobo Cosmo, and a Vexter having a thickness of 50 μm made of LCP (liquid crystal polymer) made by Kuraray. (In each case, the film width was 500 mm), a copper-clad laminated substrate was produced in the same manner as described above. Further, for Kapton 150ENC manufactured by Toray DuPont, a copper-clad laminated substrate was produced in the same manner as described above except that Cu having a thickness of 10 Å was formed instead of the formation of the Cu—Ni alloy.

[Example 2]
The long resin film F surface-treated with the surface-treating roll 14 was further surface-treated with an argon ion beam having a flow rate of 100 sccm and 2000 V by the surface-treating ion source 19, and five types were obtained in the same manner as in Example 1. A copper-clad laminated substrate was prepared.

[Comparison example]
Five types of copper-clad laminated substrates were produced in the same manner as in Example 1 except that the surface treatment with the surface treatment roll 14 was not performed.

[Evaluation]
For each of the copper-clad laminated substrates obtained in Examples 1 and 2 and Comparative Examples, the metal film was etched so that a line-shaped circuit pattern having a line width of 1 mm was formed on the metal film, and the metal film was etched at room temperature. The adhesion strength (peel strength) was measured according to IPC-TM-650, Number: 2.4.9, Revision: E, and Metal: A. The measurement results are shown in Table 1 below.

As can be seen from Table 1 above, the copper-clad laminated substrates of Examples 1 and 2 produced by applying the surface treatment method of the resin film of the present invention are copper of Comparative Example produced without applying the surface treatment method. Compared with the stretched laminated board, high adhesion was obtained regardless of the type and thickness of the resin film. Further, in Example 2 in which the surface treatment with the surface treatment roll was followed by the treatment with the argon ion beam, higher adhesion was obtained as compared with Example 1 in which the treatment with the argon ion beam was not performed.

F Long resin film F2 Polygonate film with copper thin film layer S2 Copper-clad laminate for flexible wiring substrate 1 Polygon film 2 Underlayer metal layer 3 Copper layer 3a Copper thin film layer 3b Copper electroplating layer 10 Surface treatment film deposition equipment 11 Housing 12 Unwinding roll 13a to 13n Guide roll 14 Surface treatment roll 15 Nip roll 16 Sputtering cathode for surface treatment 17 Cleaning treatment means 18 First can roll 19 Surface treatment ion source 20a Front feed roll 20b Rear feed roll 21 Second can Rolls 22a to 22d Sputtering cathode 23 Winding roll 30 Roll-to-roll continuous electroplating equipment 31 Electroplating tank 32 Unwinding roll 33a to 33e Feeding roll 34a to 34h Anodic 35a to 35d Inverting roll 36 Winding roll

Claims (7)

At least one surface of a long resin film transported by roll-to-roll under a reduced pressure atmosphere is formed on an unoxidized active metal surface on the outer peripheral surface of a surface-treated roll that rotates following the transfer of the long resin film. A surface treatment method in which the fragile layer of the long resin film is peeled off and adhered to the unoxidized active metal surface by contacting the film before the metal film is formed.
The unoxidized active metal surface is formed by sputtering means when the region of the outer peripheral surface of the surface treatment roll that comes into contact with the long resin film comes to a position that does not come into contact with the long resin film due to the rotation. A method for surface treatment of a resin film. The region of the outer peripheral surface of the surface treatment roll that comes into contact with the long resin film includes a position where the long resin film comes into contact with the rotation and a position where an unoxidized active metal surface is formed by the sputtering means. when it came between, characterized in that the cleaning process is performed, the surface treatment method of a resin film according to claim 1. The method for surface treating a resin film according to claim 2 , wherein the cleaning treatment is plasma irradiation or ion beam irradiation. On the outer peripheral surface of the surface treatment roll, the region in contact with the long resin film rotates a cycle consisting of contact with the long resin film, the cleaning treatment, and formation of the unoxidized active metal surface. The method for surface-treating a resin film according to claim 2 or 3 , wherein the method is repeated according to the above. A method for manufacturing a copper-clad laminated substrate for forming a base metal layer and a copper coating layer on at least one surface of the long resin film by a dry plating method, wherein the base metal layer is formed before the base metal layer is formed. A method for producing a copper-clad laminated substrate, characterized in that the surface is surface-treated by the surface treatment method according to any one of claims 1 to 4. A surface treatment apparatus for performing a surface treatment prior to deposition of the metal film with respect to the long resin film that is conveyed by a roll-to-roll in a vacuum container, unoxidized in contact with the surface of the front Symbol elongated resin film A surface treatment roll having an active metal surface of the above on the outer peripheral surface, peeling off the fragile layer of the long resin film by the contact and adhering to the unoxidized active metal surface is a transport path of the long resin film. When the region of the outer peripheral surface of the surface treatment roll that contacts the surface of the long resin film comes within an angle range that does not contact the long resin film due to rotation, it faces the region. A surface treatment apparatus for a long resin film, characterized in that a sputtering cathode forming the unoxidized active metal surface is arranged at a position where the film is formed. When the region of the outer peripheral surface of the surface treatment roll that contacts the surface of the long resin film comes within an angle range that does not contact the long resin film due to rotation, it is at a position facing the region and characterized in that the irradiation ion source is disposed in the plasma irradiation source or an ion beam on the front side of the sputtering cathode with respect to the rotational direction of the surface treatment roll of the long resin film according to claim 6 Surface treatment equipment.

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