JP5648402B2 - Sputtering apparatus, sputtering method, and method for producing resin film with metal base layer - Google Patents

Description

  The present invention relates to a sputtering method for forming a film by sputtering on both sides of a long resin film, a method for producing a resin film with a metal base layer using this sputtering method, and a sputtering apparatus, and a metal base applied to a flexible wiring board It can utilize suitably for manufacture of the resin film with a layer, especially manufacture of the resin film with a metal base layer which forms a metal film on both surfaces.

  Liquid crystal panels, notebook computers, digital cameras, mobile phones, etc. use a variety of flexible wiring boards obtained by coating a metal film on a heat-resistant resin film. A heat-resistant resin film with a metal film in which a metal film is formed on one surface or both surfaces of a heat-resistant resin film is used. The heat resistance resin film with a metal film is required to have flatness as the wiring pattern becomes finer and higher in density.

As a method for producing a heat-resistant resin film with a metal film as described above, conventionally, (1) a method of producing a metal foil by attaching it to a heat-resistant resin film with an adhesive,
(2) A method in which a metal foil is coated with a heat-resistant resin solution and then dried.
(3) A method of manufacturing a metal film by forming a metal film on a heat-resistant resin film by vacuum deposition (vacuum deposition, sputtering, ion plating, ion beam sputtering, etc.) or wet plating is known. ing.

  Further, in Patent Document 1, as a third manufacturing method using a vacuum film formation method or a wet plating method, a heat-resistant resin with a metal film is formed by using a sputtering method capable of forming a metal film having a low film formation speed but excellent adhesion. A method for producing a film is disclosed, and in Patent Document 2, a thin metal base layer is first formed using a sputtering method capable of forming a metal film having a low film formation rate but excellent adhesion, and then, Thus, a method of efficiently producing a heat-resistant resin film with a metal film by forming a thick metal film on the metal base layer using a wet plating method having a high film formation rate is disclosed.

  Patent Document 1 also discloses a method using two types of sputtering targets in order to further increase the adhesion of the metal film. That is, a method has been proposed in which a first metal thin film is first formed using nickel copper alloy as a sputtering target, and then a thick metal film is formed on the metal seed layer using copper or the like as a sputtering target. .

  Further, Patent Document 2 discloses a technique in which an electroplating method having a high film formation rate and a sputtering method having a low film formation rate are used in combination. The manufacturing method described in Patent Document 2 is widely used because the manufacturing method is superior to the method disclosed in Patent Document 1 using only the sputtering method.

  FIG. 1 shows the structure of a heat-resistant resin film with a metal film produced by a sputtering method and a wet plating method (electroplating method). A metal seed layer 2 and a metal base layer 3 are formed on the heat-resistant resin film 1 by a sputtering method, and a metal film 4 is formed by a wet plating method.

  There are two methods for forming the metal base layer 3 on both surfaces of the heat resistant resin film 1 by a vacuum film forming method such as a sputtering method. First, after the metal base layer 3 is formed on the surface of the heat resistant resin film 1, the metal base layer 3 is removed from the vacuum film forming apparatus, and the film is turned upside down and set again (see FIG. 1). The other method is to form a metal base layer 3 on the surface of the heat-resistant resin film 1 shown in FIG. There is a way to do it. Patent Document 3 discloses a technique in which a magnetic thin film is continuously formed on both surfaces of a continuous polymer film by a sputtering method.

  The double-side sputtering method of FIG. 2 will be described. The heat-resistant resin film 7 unwound from the unwinding roll 6 in the vacuum chamber 5 is formed on the cooling can roll 10 on the first film-forming surface by the sputtering method from the cathodes 22, 23, 24, 25, and subsequently. Then, the film is formed on the second film-forming surface on the cooling can roll 17 by the sputtering method from the cathodes 26, 27, 28, and 29, and is taken up by the take-up roll 21. The unwinding roll 6 and the winding roll 21 maintain the tension balance of the heat resistant resin film by controlling the torque of the servo motor, and a long heat resistant resin film is wound from the unwinding roll by the rotation of the can rolls 10 and 17. It is taken out and taken up on the take-up roll 21. Drive rolls 8, 12, 15, 19 and tension sensor rolls 9, 11, 16, 18 are arranged in the conveyance path from the unwinding roll 6 to the winding roll 21. In this method, the film is continuously formed on both surfaces in a vacuum. However, since the second film formation surface is formed after the film formation on the first film formation surface, not the both surfaces simultaneously, the first The stress of the film formed on the film formation surface and the film formed on the second film formation surface are different, which causes warping and undulation of the heat resistant resin film 7. However, since the film formation on the heat resistant resin film 7 requires cooling, it is necessary to cool the back surface with a cooling can roll, and simultaneous film formation on both sides is impossible.

  Further, in the method shown in FIG. 2, the film thickness increases while passing over the cooling can rolls 10, 17, but heat shrinkage / thermal expansion due to stress due to the increase in film thickness or heat load on the heat resistant resin film. Thus, if the length of the heat resistant resin film 7 is changed, excessive pulling or loosening may occur on the cooling can rolls 10 and 17.

  As described above, in the sputtering method, the temperature rise of the heat resistant resin film is a problem due to Joule heat caused by electrons flying from the sputtering source to the substrate. Patent Document 4 describes opposing sputtering in which a sputtering target is disposed inside a rectangular parallelepiped so as to face each other and has one opening. Opposite sputtering is known as a method that can reduce the temperature rise of the heat resistant resin film because electrons do not directly fly to the heat resistant resin film.

Japanese Patent No. 3447070 Japanese Patent No. 3570802 JP 2004-11023 A JP-A-2005-48227

  In view of the above-described problems, the present invention has a problem that a sputtering apparatus capable of efficiently producing a heat-resistant resin film with a double-sided metal base layer having excellent flatness and excellent productivity, and with a metal base layer. It is providing the heat-resistant resin film manufacturing method and sputtering method.

  Therefore, in order to solve the above-mentioned problem, the present inventor has at least four or more opposing sputtering units having two openings, and includes a first film formation surface (one surface of a long resin film) and a second film formation surface. An attempt was made to alternately form films on the other side of the long resin film. In addition, a film having a predetermined thickness can be formed by dividing the first film formation surface and the second film formation surface twice instead of once.

  That is, in the method of performing film formation alternately on the first film formation surface and the second film formation surface using a sputtering apparatus including an opposing sputtering unit having two openings, the first film formation surface and the second film formation surface. Since the film thickness can be increased alternately, it is only necessary to form a relatively thin film in one film formation, so that the difference in film stress between the two surfaces can be reduced.

  Therefore, the heat-resistant resin film with a metal film that can be alternately formed on the first film-forming surface and the second film-forming surface using the sputtering apparatus including the opposing sputtering unit having two openings according to the present invention. When this manufacturing method was used, it came to discover that the heat resistant resin film with a metal base layer excellent in planarity can be manufactured efficiently. The present invention has been completed based on such technical knowledge.

That is, the sputtering apparatus of the present invention for achieving the above object is
(1) A plurality of opposing sputtering units in which two openings for allowing metal electrons constituting the opposing targets to jump out from the space formed by the opposing regions are formed;
(2) One surface of the long resin film unwound from the unwinding roll on which the long resin film is wound is opposed to one of the two openings in a state where it is not wound around a roller. A plurality of guide rolls for guiding and then guiding the one surface guided to the one opening so as to face the other opening different from the one opening without being wound around the roller. The plurality of guide rolls are not provided with a cooling mechanism, and the plurality of opposed sputtering units have either one of the two openings in each of two adjacent opposed sputtering units. It arrange | positions in a row so that it may mutually oppose on both sides of a long resin film, It is characterized by the above-mentioned.

The plurality of guide rolls are:
(4) The long resin film may be guided so as to pass between the openings facing each other.

In addition, the plurality of guide rolls are
(5) A plurality of driving rolls for unwinding and transporting the long resin film from the unwinding roll may be used.

further,
(6) The plurality of drive rolls may be controlled such that the rotational speed thereof becomes faster toward the downstream side in the transport direction of the long resin film.

Furthermore,
(7) The plurality of drive rolls may be controlled such that the rotational speed thereof becomes slower toward the downstream side in the transport direction of the long resin film.

The sputtering method of the present invention for achieving the above object
(8) a first counter sputtering unit in which two openings are formed to allow metal electrons constituting a target facing each other to jump out of the space formed by the facing regions; and the first counter sputtering unit; A second counter sputtering unit having the same structure, a third counter sputtering unit having the same structure as the second counter sputtering unit, and a fourth counter sputtering unit having the same structure as the third counter sputtering unit are adjacent to each other. Arranged in a row so that one of the two openings each in the sputtering unit face each other with only the long resin film sandwiched between them,
(9) One surface of the long resin film is opposed to one of the two openings of the first opposed sputtering unit at the end of the four opposed sputtering units arranged in a row without being wound around the roller. The first guide roll without a cooling mechanism is guided to form a film on one surface thereof, and then the one surface guided to the one opening is different from the one opening. A first film forming step of forming a film on one of the formed surfaces while being guided by a second guide roll having no cooling mechanism so as to face the other opening without being wound around a roller; ,
(10) In the first film forming step, the opposite side of the one surface of the long resin film formed while being guided by a second guide roll not equipped with a cooling mechanism so as to face the other opening The surface of the second counter sputtering unit is opposed to one of the openings of the second counter sputtering unit without being wound around a roller, and then the opposite surface formed is the other surface of the second counter sputtering unit. while guided by the third guide roll having no cooling mechanism so that is opposed in a state that is not wrapped around the roller in the opening, and a second film forming step of forming superimposed on a surface of the opposite side,
(11) In the second film forming step, the one surface of the long resin film formed while being guided by a third guide roll having no cooling mechanism so as to face the other opening is The film is formed so as to face one opening of the three counter sputtering unit without being wound around the roller, and then one surface on which the film is formed is wound around the other opening of the third counter sputtering unit around the roller. while guided by the fourth guide roll having no cooling mechanism so that is opposed in the absence, and the third film formation step of forming overlaid on the one surface,
(12) In the third film-forming step, the opposite side of the one surface of the long resin film formed while being guided by a fourth guide roll having no cooling mechanism so as to face the other opening The surface of the fourth counter sputtering unit is opposed to one opening of the fourth counter sputtering unit without being wound around a roller, and then the opposite surface on which the film has been formed is the other surface of the fourth counter sputtering unit. while guiding the fifth guide roll having no cooling mechanism so that is opposed in a state that is not wrapped around the roller in the aperture, to include a fourth film forming step of forming superimposed on a surface of the opposite side It is a feature.

here,
(13) The transport speed when the first to fifth guide rolls guide the long resin film may be slower toward the downstream side in the transport direction.

Also,
(14) The conveyance speed when the first to fifth guide rolls guide the long resin film may be faster toward the downstream side in the conveyance direction.

further,
(15) The long resin film may be a long heat resistant resin film.

Furthermore,
(16) The long resin film may be composed of one kind selected from a polyimide film or an aramid film.

Furthermore, the manufacturing method of the resin film with a metal base layer of the present invention for achieving the above object is as follows.
(17) A metal seed layer of a metal thin film is formed in the first film formation step on the one surface of the long resin film by any one of the sputtering methods described above, and subsequently, on the one surface A metal seed layer is formed on the opposite surface in the second film formation step ,
(18) The metal base layer selected from Cu or Cu alloy on the surface of the metal seed layer before Symbol one surface deposited by the third deposition step, wherein the opposite surface of the one surface a metal base layer selected from Cu or Cu alloy on the surface of the metal seed layer is formed by the fourth film forming step, composed of two layers of metal seed layer and the metal base layer on both sides of the front Symbol elongated resin film The laminated body is formed into a film.

here,
(20) The metal seed layer may be Ni or a Ni alloy.

Also,
(21) The Ni alloy may be a Ni-Cr alloy layer.

  According to the sputtering apparatus of the present invention, a film is formed on one surface of a resin film guided by a guide roll in one opening of an opposing sputtering unit having two openings (first film formation). Since the film is formed with one surface facing the other opening (second film formation), only a relatively thin film needs to be formed in one film formation, reducing the difference in film stress between the two surfaces. It is possible to efficiently produce a heat-resistant resin film with a metal base layer that is excellent in flatness, and can cope with finer and higher density wiring patterns.

  Further, according to the sputtering method of the present invention, in the first film formation step, a film is formed on one surface of the long resin film, and subsequently, the film is formed on the formed one surface. In the second film formation step, a film is formed on the surface opposite to the one surface, and then the second film formation step is performed in the third film formation step. The film is formed on the surface opposite to the one surface formed in step 1, and then formed on the surface opposite to the formed film, and is formed on the one surface formed in the third film forming step. Since the film is formed on the opposite surface, and then the film is formed on the opposite surface, it is only necessary to form a relatively thin film in one film formation process. The difference in film stress can be reduced, a heat-resistant resin film with a metal base layer having excellent flatness can be efficiently produced, and it is possible to cope with finer and higher density wiring patterns.

  Furthermore, even if the heat resistant resin film with a metal base layer expands or contracts in the length direction due to the stress of the film that is alternately formed on both surfaces or the heat shrink / heat expansion of the heat resistant resin film with the metal base layer, By individually setting the rotation speed of the drive roll, it becomes possible to cope with the metal base layer-added heat resistant resin film without excessive tension or slack.

  Moreover, the manufacturing method of the heat resistant resin film with a metal base layer which concerns on this invention conveys the elongate heat resistant resin film unwound from the unwinding roll by a roll-to-roll system, and is wound around a winding roll. At the same time, at least a first film-formed surface is formed on the folded heat-resistant resin film by an opposing sputtering unit having two openings disposed between the driving rolls on the conveyance path between the unwinding roll and the winding roll. The second film-forming surface can be repeatedly formed twice, the first film-forming surface twice, and the second film-forming surface twice, and the rotational speed of these drive rolls can be set individually. It is characterized by.

It is sectional drawing which shows schematic structure of the heat resistant resin film with a metal film formed into a film by this invention. It is explanatory drawing which shows schematic structure of the manufacturing apparatus A of the heat resistant resin film with a metal base layer which concerns on a prior art. It is explanatory drawing which shows typically schematic structure of the manufacturing apparatus B of the heat resistant resin film with a metal base layer which concerns on this invention. It is explanatory drawing which shows typically schematic structure of the manufacturing apparatus C of the heat resistant resin film with a metal base layer which concerns on this invention. It is sectional drawing which shows schematic structure of the heat resistant resin film with a metal base layer formed into a film by this invention. It is explanatory drawing which shows the opposing sputtering unit schematic structure of the manufacturing apparatus of the heat resistant resin film with a metal base layer which concerns on this invention.

The sputtering method of the present invention relates to a sputtering method (film formation method) in which a film is formed on both surfaces of a heat resistant resin film of a resin film by a sputtering method. The sputtering method of the present invention will be described by taking as an example the production of a heat-resistant resin film with a metal film formed with a metal film.
1. Heat resistant resin film S with metal film

  As shown in FIG. 1, the heat resistant resin film S with a metal film has a structure in which a metal seed layer 2, a metal base layer 3, and a metal film 4 are laminated in this order on both sides of the heat resistant resin film 1 without using an adhesive. is there.

  The metal seed layer 2 is preferably formed of a nickel-chromium alloy. The thickness of the metal seed layer is desirably 5 nm to 50 nm.

  When the thickness of the metal seed layer 2 made of a nickel-chromium-based alloy containing chromium as an additive element is less than 5 nm, a problem occurs in the long-term adhesion of the metal seed layer 2 even after the subsequent processing steps. . Further, when the thickness of the metal seed layer 2 is less than 5 nm, the wiring peel strength (adhesion between the wiring and the substrate) is remarkably lowered due to the penetration of the etching solution when the wiring is processed and the wiring part floating. This is not preferable because of the above problem. On the other hand, when the layer thickness of the metal seed layer 2 exceeds 50 nm, it is difficult to remove the metal seed layer 2 during the processing of the wiring portion, and further, there may be a case where a hair crack or a warp is caused to reduce the adhesion strength. Therefore, it is not preferable. Further, if the layer thickness is greater than 50 nm, it is difficult to perform etching, which is not preferable.

  The component composition of the metal seed layer 2 is required to have a chromium ratio of 5 to 40 atomic% from the viewpoint of heat resistance and corrosion resistance, and a more desirable chromium ratio is 12 to 22 atomic%. That is, when the chromium ratio is less than 5 atomic%, the heat resistance is lowered. On the other hand, when the chromium ratio exceeds 40 atomic%, it is difficult to remove the metal seed layer 2 when processing the wiring portion. This is not preferable. Furthermore, other transition metal elements such as molybdenum and vanadium can be appropriately added to the nickel-chromium alloy in accordance with the purpose and characteristics in order to improve heat resistance and corrosion resistance. Note that the composition of the metal seed layer is determined in consideration of improvement in corrosion resistance and insulation reliability and workability of the wiring portion.

  The thickness of the metal base layer 3 is desirably 50 nm to 1000 nm or less, and more desirably 50 nm to 500 nm. Copper is used for the metal base layer.

  The metal film 4 is formed on the surface of the metal base layer 3 as necessary. The metal film 4 is preferably formed of copper because it is processed by wiring and becomes a conductor. The thickness including the metal base layer 3 and the metal film 4 is preferably 10 nm to 12 μm. The thickness of the metal film 4 can be appropriately selected according to a wiring pattern forming method to be described later, and the metal film 4 can be appropriately selected not to be provided.

  As the heat resistant resin film, a resin film selected from a polyimide film, a polyamide film, a polyester film, a polytetrafluoroethylene film, a polyphenylene sulfide film, a polyethylene naphthalate film or a liquid crystal polymer film is a metal film. This is preferable from the viewpoints of flexibility as an attached flexible substrate, strength necessary for practical use, and electrical insulation suitable as a wiring material.

  The manufacturing procedure of the heat resistant resin film S with a metal film is as follows. The seed layer 2 is formed on the surface of the heat resistant resin film 1 and the metal base layer 3 is formed on the surface of each metal seed layer 2 by sputtering. A heat-resistant resin film with a heat treatment is manufactured, and subsequently, a metal film 4 is formed on the surface of each metal base layer 3 by a wet plating method. As the wet plating method, a known electroless plating method or electrolytic plating method can be used, and a plurality of wet plating methods may be combined.

2. Film Forming Apparatus The film forming apparatus of the present invention can be applied as means for forming the metal seed layer 2 and the metal base layer 3 on both sides of a long resin film.
The film forming apparatus of the present invention conveys a long heat-resistant resin film unwound from an unwinding roll by a roll-to-roll method and winds it on a winding roll, and on the surface of the heat-resistant resin film. In a sputtering apparatus for forming a film by a sputtering method, four or more adjacent drive rolls (an example of a guide roll according to the present invention, which is an example of a guide roll in the present invention, on a conveyance path between a winding roll and a winding roll. Also has a function.) Is arranged to constitute a conveyance path for turning back the heat-resistant resin film, and is disposed between the drive rolls and has two openings that are open to the conveyance path. A film forming process for forming a film at least twice on the first film forming surface, twice on the second film forming surface, twice on the first film forming surface, and twice on the second film forming surface. The repeating in sequence, a sputtering apparatus, wherein a film can be formed by overlapping a plurality of thin films on both sides of the long resin film. By providing four or more driving rolls that fold the heat-resistant resin film conveyance path, and providing four or more folding points on the heat-resistant resin film conveyance path, providing four or more opposing sputtering units. Is possible. By providing four or more opposed sputtering units, sputtering film formation by two or more opposed sputtering units is possible on each surface of the heat-resistant resin film, and a laminate of two or more different sputtering films or a film of sputtering films The thickness can be increased.

  The unwinding roll and take-up roll maintain the tension balance of the heat-resistant resin film by the torque control of the servo motor, and the long heat-resistant resin film is unwound from the unwinding roll by the rotation of the drive roll. It is wound on a winding roll.

  3. Equipment for manufacturing heat-resistant resin film with metal base layer

  An apparatus for producing a heat resistant resin film with a metal base layer using the sputtering method and film forming apparatus of the present invention for producing the heat resistant resin film with a metal base layer will be described in detail with reference to FIGS. 3 and 4 have basically the same configuration, and the difference between them is that the position and number of drive rolls and the number of opposed sputtering units having two openings are different. Although the number of times of film formation on the first film formation surface is the same as that of the second film formation surface in the asymmetric structure, the apparatus configuration in FIG. 4 is a symmetric structure, but the first film formation surface and the second film formation surface are formed. The number of membranes is different.

  The manufacturing apparatus B (sputtering apparatus B) of the heat resistant resin film with a metal base layer of this invention is demonstrated in detail using FIG.

  In the sparing vacuum chamber 110 of the sputtering apparatus B, an unwinding roll 111 around which a heat-resistant resin film 112 (an example of a long resin film according to the present invention) is wound is disposed. The heat resistant resin film 112 unwound from the roll 111 has two openings having openings in the direction of the heat resistant resin film 112 while being folded by the drive rolls 118, 119, 120, 121, 122, 123. Film formation proceeds simultaneously on the first film formation surface and the second film formation surface of the heat resistant resin film 112 by at least four units of the opposing sputtering units 129, 130, 131, and 132. (However, one side of the opposite sputtering unit at both ends is a single-side film formation). The film formation in the facing sputtering unit 129 is the first film formation process referred to in the present invention. The film formation in the facing sputtering unit 130 is the second film forming process according to the present invention, and the film forming in the facing sputtering unit 131 is the third film forming process according to the present invention, and the film forming in the facing sputtering unit 132 is performed. Is the fourth film forming step according to the present invention.

  In this way, the film is wound on the winding roll 128 while the film thickness on both sides alternately increases.

  The unwinding roll 111 and the winding roll 128 maintain the tension balance of the heat-resistant resin film by torque control of the servo motor, and the long heat-resistant resin film 112 is unwound from the unwinding roll by the rotation of the driving roll. Then, it is wound around the winding roll 128. In the meantime, driving rolls 115 and 125, tension sensor rolls 114 and 126, and free rolls 113, 116, 117, 124, and 127 are arranged.

Four units of opposing sputtering units 129, 130, 131, and 132 alternately form films on the first film formation surface (one surface in the present invention) and the second film formation surface (the opposite surface in the present invention). In the method to be performed, it is possible to alternately increase the film thickness of the first film formation surface and the second film formation surface, so that the difference in film stress between the both surfaces can be reduced, and warping and undulation can be suppressed to achieve flatness. An excellent heat-resistant resin film with a metal base layer can be efficiently produced.
Furthermore, even if the length of the heat-resistant resin film with the metal base layer expands or contracts due to the stress of the film alternately formed on both surfaces or the heat shrinkage / thermal expansion of the heat-resistant resin film with the metal base layer, the drive roll By individually setting the rotation speed, it is possible to cope with the heat resistance resin film with a metal base layer without excessive pulling or slackening.

  The manufacturing apparatus C of the heat resistant resin film with a metal base layer of this invention is demonstrated with reference to FIG.

  Considering performing reverse film formation, a highly symmetric structure is desirable. The manufacturing apparatus C for the heat-resistant resin film with a metal base layer in FIG. 4 increases symmetry by increasing the number of opposing sputtering units by one unit as compared with the manufacturing apparatus B for a heat-resistant resin film with a metal base layer in FIG. This is a sputtering apparatus having a structure suitable for a product in which film formation is performed while reciprocating.

  The heat resistant resin film 142 unwound from the unwinding roll 141 in the vacuum chamber 140 is turned in the direction of the heat resistant resin film 142 while being folded by the drive rolls 147, 148, 149, 150, 151, 152, 153. At least 5 units of opposing sputtering units 159, 160, 161, 162, and 163 having two openings with openings simultaneously form films on the first film-forming surface and the second film-forming surface of the heat-resistant resin film 142. proceed. (However, one side of the opposite sputtering unit at both ends is a single-sided film)

  And it winds up by the winding roll 158, the film thickness of both surfaces increasing alternately.

The unwinding roll 141 and the winding roll 158 maintain the tension balance of the heat resistant resin film by controlling the torque of the servo motor, and the long heat resistant resin film 142 is unwound from the unwinding roll by the rotation of the driving roll. Then, it is wound on a winding roll 158. During this time, drive rolls 145 and 155, tension sensor rolls 144 and 156, and free rolls 143, 146, 154, and 156 are arranged.
In the method of alternately forming films on the first film formation surface and the second film formation surface with the five units of the opposing sputtering units 159, 160, 161, 162, and 163, the film on the first film formation surface and the second film formation surface Since the thickness can be increased alternately, the difference in film stress between the two surfaces can be reduced, and a heat resistant resin film with a metal base layer having excellent flatness can be efficiently produced. Since there are 3 units of opposing sputtering units on the first film-forming surface and 2 units of opposing sputtering units on the 2nd film-forming surface, the sputtering power (voltage, current) of each cathode is adjusted to achieve the same film thickness on both sides. There is a need to.
Furthermore, even if the length of the heat-resistant resin film with the metal base layer expands or contracts due to the stress of the film alternately formed on both surfaces or the heat shrinkage / thermal expansion of the heat-resistant resin film with the metal base layer, the drive roll By individually setting the rotation speed, it is possible to cope with the heat resistance resin film with a metal base layer without excessive pulling or slackening.

The apparatus for producing a heat-resistant resin film with a metal base layer of the present invention may be provided with a drying process by heating with a heater or a pre-process using ion beam / plasma on both sides before film formation. In the apparatus of the present invention, the direction of the rotation axis of each roll is not limited to the horizontal direction, but may be arranged in the horizontal direction, vertical or vertical. Furthermore, even if two or more opposing sputtering units are installed between the drive rolls, the opposing sputtering units that sandwich the heat-resistant resin film do not have to be in front of each other, and may be arranged in a staggered manner.
4). In the facing sputtering unit sputtering method, the temperature rise of the heat resistant resin film is a problem due to Joule heat caused by electrons flying from the sputtering source to the substrate. In particular, since a flat target is an arrangement in which electrons from a sputter fly directly to a substrate, even a heat-resistant resin film may cause thermal shrinkage or wrinkles due to a thermal load. In order to prevent this, it is necessary to cool by a water-cooled can roll or the like from the back side of the heat-resistant resin film during sputtering film formation. However, since this water-cooled can roll has a complicated internal structure and is heavy, the rotating mechanism and the like become a large-scale mechanism. However, since the sputtering target is disposed inside the rectangular parallelepiped so that the sputtering targets face each other, since the electrons do not fly directly to the heat resistant resin film, the temperature rise of the heat resistant resin film can be reduced. Therefore, a very simple sputtering apparatus can be configured.

  The counter sputtering unit X used in the present invention shown in FIG. 6 has two targets 170 and 171 facing each other, and on the back side there are cathode units 172 and 173 which are magnetic circuits, which surround these two targets. Thus, the surrounding plates 174 and 175 are installed. And it has two opening parts (it is an example of the opening said to this invention). You may arrange | position a target on four surfaces other than an opening part. Further, the “space formed by the opposed regions” in the present invention is also a space T sandwiched between the surrounding plates 174 and 175.

  For example, in the sputtering apparatus B, the two openings of the opposing sputtering unit X face the heat-resistant resin films before and after being folded by the drive rolls 119, 120, 121, and 122. The second film formation can be performed by passing through the drive roll, and only a thin film needs to be formed in one film formation, so that the difference in film stress between both surfaces can be reduced.

Even when the counter sputtering unit X is used, the inside of the driving rolls 118, 119, 120, 121, 122, 123 of the sputtering apparatus B and the driving rolls 147, 148, 149, 150, 151, 152, 153 of the sputtering apparatus C A liquid for cooling or heating may be circulated. By circulating the cooling or heating liquid inside these drive rolls, it is possible to further suppress the temperature change of the heat resistant resin film during film formation.
5. Metal film

  When a metal film is formed on the metal base layer of the obtained heat-resistant resin film with a metal base layer using a wet plating method, the electroplating process is performed alone, or the electroless plating process is performed as the primary plating. In some cases, wet plating such as electrolytic plating is combined as the next plating. The wet plating process may employ various conditions of a conventional wet plating method.

And the difference of the film | membrane stress of both surfaces was reduced by further forming a metal film by the wet-plating method on the surface of the metal base layer of the heat resistant resin film with a metal base layer obtained by the sputtering method of this invention. It becomes possible to obtain a heat-resistant resin film with a metal film. The total of the metal seed layer and the metal base layer by the dry plating method (sputtering method) formed on the metal seed layer in this way and the metal layer (the metal base layer and the metal film) by the wet plating method, respectively. The thickness is preferably at most 20 μm.
6). Wiring pattern

  Using the heat-resistant resin film with a metal film thus obtained, a wiring pattern is individually formed on at least one surface of the heat-resistant resin film with a metal film. In addition, via holes for interlayer connection can be formed at predetermined positions and used for various purposes. More specifically, (1) a wiring pattern is formed and used individually on at least one side of a heat-resistant resin film with a metal film. (2) A via hole penetrating the heat-resistant resin film is formed and used with the heat-resistant resin film with a metal film on which a wiring pattern is formed. (3) In some cases, the via hole is filled with a conductive material to make the hole conductive.

As a method for forming the wiring pattern, a known subtractive method or semi-additive method can be used.
In the subtractive method, an unnecessary metal film, a metal base layer, and a metal seed layer of the heat-resistant resin film with a metal film are removed by chemical etching to form a wiring pattern. Prepare a heat-resistant resin film with a metal film, and form a photosensitive resist film by laminating screen printing or dry film on the metal film, and then pattern it so that the resist film remains at the location of the wiring pattern by exposure and development. To do. Next, the metal film is selectively removed by etching with an etchant such as a ferric chloride solution, and then the resist film is removed to form a predetermined wiring pattern. It is preferable to process the wiring pattern on both sides. Whether or not all the wiring patterns are divided into several wiring regions depends on the distribution of the wiring density of the wiring patterns. For example, the wiring pattern is divided into a high-density wiring area and a wiring area each having a wiring width and a wiring interval of 50 μm or less, and the wiring pattern is divided in consideration of the difference in thermal expansion from the printed circuit board and the handling convenience. What is necessary is just to divide suitably, setting a size to about 10-65 mm.

  As a method for forming the via hole, a conventionally known method can be used. For example, a via hole penetrating the wiring pattern and the heat resistant resin film is formed at a predetermined position of the wiring pattern by laser processing or the like. The diameter of the via hole is preferably reduced within a range that does not hinder the conductivity in the hole, and is usually 100 μm or less, preferably 50 μm or less. The via hole is filled with a conductive metal such as copper by plating, vapor deposition, sputtering, etc., or a conductive paste is pressed and dried using a mask having a predetermined opening pattern, and the inside of the hole is made conductive to form an interlayer. Make electrical connections.

  In the semi-additive method, a thick wiring film is formed on the surface of the metal film of the heat-resistant resin film with a metal film by wet plating only at the place where the wiring pattern is to be provided, and then the unnecessary metal film and metal base are formed by soft etching. A wiring method for removing the layer and the metal seed layer. After preparing a heat-resistant resin film with a metal film and laminating a screen printing or dry film on the metal film to form a photosensitive resist film, the resist film is exposed and developed to expose the location of the wiring pattern. Pattern so that it remains. After exposure and development of the resist, a thick wiring pattern is formed by a wet plating method, and then a metal film unnecessary for the wiring pattern is removed by soft etching (chemical etching). The formation of via holes is the same as in the subtractive method. In addition, when forming a wiring pattern by a semi-additive method, you may use the heat resistant resin film with a metal base layer which has not formed the metal film by the wet-plating method.

  So far, the description has focused on a method for producing a resin film substrate with a metal base layer in which a metal seed layer and a metal base layer are formed on both surfaces of a heat resistant resin film of the resin film. In the present invention, the metal seed layer and the metal base layer are not limited to the sputtering film formation on both surfaces of the resin film, and it is needless to say that an oxide film, a nitride film, or the like can be used for the sputtering film formation.

  Examples of the present invention will be specifically described below.

  Using the manufacturing apparatus B of the heat resistant resin film with a metal base layer of the present invention shown in FIG. 3, the long heat resistant resin film 112 has a width of 500 mm, a length of 200 m, and a thickness of 25 μm manufactured by Ube Industries, Ltd. Heat-resistant polyimide film “UPILEX S (registered trademark)” was used.

  Ni—Cr target (manufactured by Sumitomo Metal Mining Co., Ltd.), which is a metal seed layer target, is used for the opposing sputtering units 129, 130, and Cu target (Sumitomo Metal), which is a metal base layer target, is used for the opposing sputtering units 131, 132. Mining Co., Ltd.) was used.

First, it was evacuated to 5 Pa using a dry pump, and then evacuated to 1 × 10 ⁻³ Pa using a turbo molecular pump and a cryocoil, and 200 sccm of Ar gas was introduced near each cathode. At a film conveyance speed of 2 m / min, a DC sputtering power of 5 kW was applied to the opposing sputtering units 129 and 130 for the metal seed layer, and 15 kW was applied to the opposing sputtering units 131 and 132 for the metal base layer. Further, tension control was performed so that the tension of the tension sensor rolls 114 and 126 was 80N. Assuming that the rotation speed of the driving roll 118 with respect to the film conveyance speed of 2 m / min is 100%, the driving roll 119 is 100.2%, the driving roll 120 is 100.4%, the driving roll 121 is 100.6%, and the driving roll 122 is 100.8% and the driving roll 123 were set to increase to 101.0%. The reason for this setting is that the heat-resistant resin film with a metal base layer tends to be stretched under the heat-resistant resin film and the film formation conditions. Of course, if it is a heat-resistant resin film with a metal base layer that tends to shrink, the deceleration setting may be used.

  After 500 m double-sided film formation, the film transport is stopped, Ar gas introduction is stopped, and each pump is stopped and vented (open to the atmosphere), and the end portion of the heat-resistant polyimide film of the unwinding roll is removed, All films were taken up on a take-up roll and then removed.

Then, as shown in FIG. 5, a part of the obtained heat-resistant resin film with a metal base layer was cut out, and the first film-formed surface (Cu metal seed layer and metal formed on one surface of the film) Base layer) and the second film-forming surface (Cu metal seed layer and metal base layer formed on the other surface of the film) are partially etched, and the metal seed layer formed on each surface As a result of measuring a certain Ni—Cr layer film thickness and a metal base layer Cu layer film thickness with a fluorescent X-ray film thickness meter, both the first film formation surface and the second film formation surface have a Ni—Cr layer film thickness of about 15 nm, The Cu layer thickness was about 150 nm.
[Comparative example]

  As in the example, the manufacturing apparatus A for heat resistant resin film with metal base layer shown in FIG. 2 was used, and the long heat resistant resin film 142 had a width of 500 mm, a length of 200 m, and a thickness of 25 μm. A heat-resistant polyimide film “UPILEX S (registered trademark)” manufactured by Co., Ltd. was used.

  Ni-Cr targets (manufactured by Sumitomo Metal Mining Co., Ltd.) are used for the cathodes 22 and 26 of the metal seed layer, and Cu targets (Sumitomo Metal Mining Co., Ltd.) are used for the cathodes 23, 24, 25, 27, 28, and 29 of the metal base layer. Used).

First, it was evacuated to 5 Pa using a dry pump, and then evacuated to 1 × 10 ⁻³ Pa using a turbo molecular pump and a cryocoil, and 200 sccm of Ar gas was introduced near each cathode. At a film conveyance speed of 2 m / min, DC sputtering power of 5 kW was applied to the cathodes 22 and 26 of the metal seed layer and 6 kW to the cathodes 23, 24, 25, 27, 28, and 29 of the metal base layer. Moreover, tension control was performed so that the tension of the tension sensor rolls 9, 11, 16, and 18 was 80N. When the rotation speed of the water-cooled can roll 10 with respect to the film conveyance speed of 2 m / min is 100%, the water-cooled can roll 17 is set to increase to 101.5%. The reason for this setting is that the heat-resistant resin film with a metal base layer tends to be stretched under the heat-resistant resin film and the film formation conditions. Of course, if it is a heat-resistant resin film with a metal base layer that tends to shrink, the deceleration setting may be used.

  After 500 m double-sided film formation, the film transport is stopped, Ar gas introduction is stopped, and each pump is stopped and vented (open to the atmosphere), and the end portion of the heat-resistant polyimide film of the unwinding roll is removed, All films were taken up on a take-up roll and then removed.

  Then, as shown in FIG. 5, a part of the obtained heat-resistant resin film 100 with a metal base layer is cut out, and a first film-formed surface (a metal made of Ni—Cr formed on one surface of the film) is obtained. The seed layer 120 and the metal base layer made of Cu) and the second film-forming surface (the metal seed layer 120 made of Ni—Cr and the metal base layer 130 made of Cu formed on the other surface of the film) are partially formed. As a result of etching and measuring the film thickness of the Ni—Cr layer, which is a metal seed layer formed on each surface, and the film thickness of the metal base layer Cu with a fluorescent X-ray film thickness meter, On the second film-forming surface, the Ni—Cr layer thickness was about 15 nm and the Cu layer thickness was about 150 nm.

  "Evaluation"

  The flatness of the heat resistant resin film with a metal base layer produced in the Example of this invention and the heat resistant resin film with a metal base layer produced in the comparative example of the prior art was compared.

Ten heat-resistant resin films with both metal base layers were cut into a circle having a diameter of 30 mm, and the maximum gap was measured on a metal surface plate. As a result, the average value of the maximum gap of the heat-resistant resin film with metal base layer produced in the examples of the present invention was 0.1 mm or less (unmeasurable level), and the heat resistance with metal base layer produced in the comparative example of the prior art. The average value of the maximum gap of the resin film was 0.3 mm.
Moreover, although this invention does not employ | adopt water-cooled can roll, generation | occurrence | production of the wrinkles which can be visually confirmed similarly to the heat resistant resin film with a metal base layer produced by the comparative example (adopting water-cooled can roll) of a prior art There was no.

  And since the heat resistance resin film with a metal base layer manufactured by the sputtering apparatus (manufacturing apparatus) according to the present invention alternately increased the film thickness on both sides, the film stress is equal to that of the prior art, so the flatness is excellent. It can cope with finer and higher density wiring patterns.

  According to the manufacturing apparatus according to the present invention, a heat-resistant resin film with a metal base layer having excellent flatness can be efficiently produced. Therefore, a heat-resistant resin with a metal film obtained from this heat-resistant resin film with a metal base layer The film has industrial applicability in which the film can be applied to flexible wiring such as liquid crystal televisions and mobile phones.

DESCRIPTION OF SYMBOLS 1 Heat resistant resin film 2,120 Metal seed layer by sputtering method 3,130 Metal base layer by sputtering method 4 Metal film by wet plating method 5 110,140 Vacuum chamber of manufacturing apparatus of heat resistant resin film with metal base layer 6, 21, 128, 158 Winding roll 8, 12, 15, 19, 115, 118, 119, 120, 121, 122, 123, 125, 145, 147, 148, 149, 150, 151, 152, 153, 155 Roll 13, 14, 20, 33, 34, 36, 46, 47, 73, 74, 86, 87, 113, 116, 117, 124, 127, 143, 146, 154, 157 Free roll 114, 126, 144, 156 Tension sensor roll 129, 130, 131, 132, 159, 16 0,161,162,163 Opposite sputtering unit 7,112,142,100 Heat resistant resin film (heat resistant polyimide film)
6,111,141 Unwinding roll 170,171 Target 172,173 Cathode unit 174,175 Shield plate

Claims (13)

A plurality of opposing sputtering units in which two openings are formed for the metal electrons constituting the opposing targets to jump out from the space formed by the opposing regions;
Guiding one surface of the long resin film unwound from the unwinding roll on which the long resin film is wound so as to face one of the two openings without being wound around a roller, And a plurality of guide rolls for guiding the one surface guided to the one opening to face the other opening different from the one opening without being wound around the roller,
The plurality of guide rolls do not have a cooling mechanism,
The plurality of opposed sputtering units are arranged in a row such that any one of the two openings in each of two adjacent opposed sputtering units faces each other with only a long resin film interposed therebetween. A sputtering apparatus characterized by that.   The sputtering apparatus according to claim 1, wherein the plurality of guide rolls guide the long resin film so as to pass between the openings facing each other.   The sputtering apparatus according to claim 1, wherein the plurality of guide rolls are a plurality of driving rolls for unwinding and transporting the long resin film from the unwinding roll. 4. The sputtering apparatus according to claim 3, wherein the plurality of drive rolls are controlled such that a rotational speed thereof is increased toward a downstream side in a conveyance direction of the long resin film. 5. The sputtering apparatus according to claim 3, wherein the plurality of driving rolls are controlled such that the rotational speed thereof becomes slower toward the downstream side in the conveyance direction of the long resin film. A first opposing sputtering unit having two openings for allowing metal electrons constituting the opposing targets to jump out of the space formed by the opposing regions, and having the same structure as the first opposing sputtering unit In two adjacent opposing sputtering units, a second opposing sputtering unit, a third opposing sputtering unit having the same structure as the second opposing sputtering unit, and a fourth opposing sputtering unit having the same structure as the third opposing sputtering unit are combined. Arranged in a row so that either one of the two openings each has, facing each other only sandwich the long resin film,
One surface of the long resin film is opposed to one opening of the two openings of the first opposed sputtering unit at the end of the four opposed sputtering units arranged in a row without being wound around the roller. Guided by a first guide roll that does not have a cooling mechanism, a film is formed on the one surface, and then the one surface guided by the one opening is formed on the other opening different from the one opening. A first film forming step of forming a film on one of the formed surfaces while being guided by a second guide roll not equipped with a cooling mechanism so as to face the roller without being wound around the roller;
In the first film formation step, a surface opposite to the one surface of the long resin film formed while being guided by a second guide roll having no cooling mechanism so as to face the other opening. A film is formed so as to face one opening of the second counter sputtering unit without being wound around a roller, and then the opposite surface on which the film has been formed is formed into a roller on the other opening of the second counter sputtering unit. a second film forming process while guided by the third guide roll having no cooling mechanism so that is opposed, forming superimposed on a surface of the opposite side in a state not wrapped around the,
In the second film forming step, the one surface of the long resin film formed while being guided by a third guide roll having no cooling mechanism so as to face the other opening is formed by the third counter sputtering. The film is formed so as to face one of the openings of the unit without being wound around the roller, and then, the one surface on which the film is formed is not wound around the other opening of the third facing sputtering unit. while guided by the fourth guide roll having no cooling mechanism so that is opposed, and the third film formation step of forming overlaid on the one surface,
In the third film forming step, a surface opposite to the one surface of the long resin film formed while being guided by a fourth guide roll having no cooling mechanism so as to face the other opening. A film is formed so as to face one opening of the fourth counter sputtering unit without being wound around a roller, and then the opposite surface on which the film has been formed is transferred to the other opening of the fourth counter sputtering unit. while guiding the fifth guide roll which is not provided a cooling mechanism so that is opposed by non wrapped around the, characterized in that it comprises a fourth film forming step of forming superimposed on a surface of the opposite side Sputtering method. The sputtering method according to claim 6, wherein a conveying speed when the first to fifth guide rolls guide the long resin film becomes slower toward a downstream side in the conveying direction. . The sputtering method according to claim 6, wherein a conveyance speed when the first to fifth guide rolls guide the long resin film is increased toward a downstream side in the conveyance direction. .   The sputtering method according to any one of claims 6 to 8, wherein the long resin film is a long heat-resistant resin film. The said long resin film is comprised by 1 type chosen from a polyimide film or an aramid film, The sputtering method as described in any one of Claim 6 to 9 characterized by the above-mentioned. A metal seed layer of a metal thin film is formed in the first film formation step on the one surface of the long resin film by the sputtering method according to claim 6, and subsequently , Forming a metal seed layer on the surface opposite to the one surface in the second film formation step ,
A metal base layer selected from Cu or Cu alloy on the surface of the metal seed layer before Symbol one surface deposited by the third film forming step, the metal seed layer on the opposite side surface of the one surface the metal base layer selected from Cu or Cu alloy is deposited by the fourth film forming step on the surface, both sides in the metal seed layer and the laminate comprising two layers of the metal base layer before Symbol elongated resin film A method for producing a resin film with a metal base layer, characterized by forming a film.   The method for producing a resin film with a metal base layer according to claim 11, wherein the metal seed layer is Ni or a Ni alloy.   The said Ni alloy is a Ni-Cr alloy layer, The manufacturing method of the resin film with a metal base layer of Claim 12 characterized by the above-mentioned.

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