JP2016041840A - Deposition method, and manufacturing method of resin film with metal film using the deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently practicing a heat-loaded deposition processing with few wrinkles generated.SOLUTION: A cylindrical can roll 56 is equipped with a refrigerant circulation part 11 in the inside, a plurality of gas passages 14 at its thick outer peripheral part, and gas discharging holes 15 that start from each of the gas passages 14, arranged along the extending direction of the gas passages 14 with almost the same distance from each other over its whole circumference. The outer peripheral surface of the can roll 56 is wound with a long-sized resin film F conveyed by a roll-to-roll method under a reduced pressure. In a deposition method of the long-sized resin film F, a thin film is formed on the front side of the resin film F while cooled from the back side of the resin film F. The long-sized resin film F winding around the outer peripheral surface has a plurality of protrusions P projecting toward the outer peripheral surface, the protrusions P being formed at both the ends in its width direction along its longitudinal direction.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method for forming a film on a flexible thin film member such as a film under reduced pressure and a method for producing a resin film with a metal film using the same, and particularly wrinkles are generated by a thermal load applied during film formation. The present invention relates to a film forming method for forming a film while cooling a flexible thin film member through gas so as to suppress the above, and a method for producing a resin film with a metal film using the same.

  Liquid crystal panels, notebook computers, digital cameras, mobile phones, and the like use flexible wiring boards in which an electric circuit is formed on a heat-resistant resin film. Such a flexible wiring board is manufactured by applying a thin film technique such as photolithography or etching to a heat-resistant resin film with a metal film in which a metal film is formed on one or both surfaces of the heat-resistant resin film. In recent years, the wiring pattern of a flexible wiring board has been increasingly miniaturized and densified, and the above-described heat-resistant resin film with a metal film as a base material thereof is required to be flatter and free from wrinkles.

  As a manufacturing method of this type of heat-resistant resin film with a metal film, a method of conventionally manufacturing a metal foil by attaching it to a heat-resistant resin film with an adhesive (a method of manufacturing a three-layer substrate), a heat-resistant resin on a metal foil Manufacturing method by coating solution and drying to manufacture (casting method) or heat-resistant resin film by vacuum film forming method or by combination of vacuum film forming method and wet plating method A method (metalizing method) or the like is known. Examples of the vacuum film forming method in the metalizing method include a vacuum deposition method, a sputtering method, an ion plating method, and an ion beam sputtering method.

  As for the metallizing method, Patent Document 1 discloses a method of forming a conductor layer on a polyimide insulating layer by sputtering chromium on the polyimide insulating layer and then sputtering copper. Further, in Patent Document 2, a first metal thin film formed by sputtering using a copper-nickel alloy as a target and a second metal thin film formed by sputtering using a copper as a target are arranged on a polyimide film in this order. The material for flexible circuit boards obtained by laminating | stacking on is disclosed.

  By the way, among the vacuum film forming methods described above, the sputtering method is generally excellent in adhesion, but it is said that the heat load applied to the heat resistant resin film is larger than that in the vacuum vapor deposition method. It is also known that when a large heat load is applied to the heat resistant resin film during film formation, the film is likely to be wrinkled. Therefore, when a heat-resistant resin film such as a polyimide film is used for the substrate, a manufacturing apparatus for a heat-resistant resin film with a metal film generally called a sputtering web coater is used. The sputtering web coater is equipped with a rotating can roll having a cooling function, and is formed by winding a heat-resistant resin film conveyed by roll-to-roll around a conveyance path defined on the outer peripheral surface thereof. It becomes possible to cool the heat resistant resin film during the sputtering process from the back side. This makes it possible to perform film formation with a heat load while suppressing generation of wrinkles.

  For example, Patent Document 3 discloses an unwinding type (roll-to-roll type) vacuum sputtering apparatus which is an example of a sputtering web coater. The unwinding / winding-type vacuum sputtering apparatus is provided with a cooling roll that plays the role of the above-mentioned can roll, and the film is turned into a cooling roll by a sub-roll provided at least on the film feeding side or the feeding side of the cooling roll. Control to adhere is performed.

  However, as described in Non-Patent Document 1, since the outer peripheral surface of the can roll as a cooling mechanism is not flat when viewed microscopically, the can roll and the film conveyed in close contact with the outer peripheral surface There is a gap portion (gap) that is separated via a vacuum space. For this reason, it can not be said that the heat of the film generated during sputtering or vapor deposition is actually efficiently transferred from the film to the can roll, and this causes wrinkling of the film. In order to solve this problem, a technique has been proposed in which gas is introduced from the can roll side into the gap portion between the outer surface of the can roll and the film so that the thermal conductivity of the gap portion is higher than that of vacuum. Yes.

  For example, Patent Document 4 discloses a technique for providing a large number of fine holes serving as gas discharge ports on the outer peripheral surface of the can roll as a specific method for introducing gas into the gap portion from the can roll side. . Patent Document 5 discloses a technique for providing a groove serving as a gas discharge port on the outer peripheral surface of a can roll. Furthermore, a method is also known in which the can roll itself is composed of a porous body, and the micropores of the porous body itself are used as gas discharge ports.

Japanese Patent Laid-Open No. 2-98994 Japanese Patent No. 3447070 Japanese Patent Laid-Open No. 62-247073 International Publication No. 2005/001157 U.S. Pat. No. 3,414,048

"Vacuum Heat Transfer Models for Web Substrates: Review of Theory and Experimental Heat Transfer Data," 2000 Society of Vacuum Coaters, 43rd. Annual Technical Conference Proceeding, Denver, April 15-20, 2000, p.335

  As described above, when gas is released from the outer peripheral surface side between the outer peripheral surface of the can roll and the film wound around the can roll, the film floats from the outer peripheral surface by the gas pressure of the released gas. However, in this case, the gas pressure at both ends in the width direction of the film may be lower than that at the center in the width direction, and the gap interval at both ends becomes narrower than the gap interval at the center. Wrinkles may occur due to contact with the outer peripheral surface of the can roll.

  The present invention has been made paying attention to such conventional problems, and hardly causes wrinkles on a long flexible thin plate member conveyed by a roll-to-roll method under reduced pressure. It is an object of the present invention to provide a method for efficiently performing a film forming process with a heat load.

  In order to achieve the above object, the present inventor winds a film around the outer peripheral surface of a cylindrical can roll having a refrigerant circulation portion inside and a gas release mechanism for releasing gas from the outer peripheral surface, and cools it from the back side. While intensive research on the method of forming a thin film on the surface side while providing a convex portion protruding in the direction toward the outer peripheral surface at both ends in the width direction of the film wound around the outer peripheral surface of the can roll, It has become possible to reduce the frictional force due to the contact between the outer peripheral surface and both ends of the film in the width direction, and found that wrinkles can be effectively suppressed, and the present invention has been completed.

  That is, the film forming method provided by the present invention has a refrigerant circulation portion inside and a plurality of gas flow passages in the outer peripheral thick portion, and openings from each of them along the extending direction of the gas flow passage on the outer peripheral surface side. The length of the gas discharge hole group that is transported in a roll-to-roll manner under reduced pressure to the outer peripheral surface of a cylindrical cooling mechanism that is disposed over the entire circumference at substantially equal intervals in the circumferential direction Is a film forming method of a flexible thin plate member that forms a thin film on the front surface side while cooling from the back surface side, and the flexible thin plate member wound around the outer peripheral surface is A plurality of convex portions protruding toward the outer peripheral surface are formed along the longitudinal direction at both end portions in the width direction.

  According to the present invention, when film formation is performed while winding a long flexible thin plate member around a cooling mechanism having a gas release mechanism and cooling, the frictional force caused by the contact between the flexible thin plate member and the cooling mechanism. As a result, the flexible thin plate member can be deformed relatively freely in the width direction when a force is applied to the flexible thin plate member to apply a heat load. Generation of wrinkles can be suppressed. Thereby, it is possible to efficiently produce a flexible thin plate member on which a film having an excellent appearance and a stable film quality is formed. By using this film forming method of the flexible thin plate member in the sputtering process of the resin film with a metal film, it becomes possible to efficiently produce a resin film with a metal film without wrinkles.

It is a front view which shows the sputtering web coater which is an example of the processing apparatus with which the film-forming method of this invention is used suitably. It is sectional drawing which cut | disconnected the can roll with a gas introduction mechanism used for the sputtering web coater of FIG. 1 in the surface which passes along the central axis. It is a perspective view of the rotary joint which the can roll of FIG. 2 comprises. In the conventional film-forming method, it is sectional drawing which shows typically the behavior of this flexible thin plate member when a thermal load is applied to the flexible thin plate member wound around the cooling mechanism provided with the gas discharge | release mechanism. In the film-forming method of one specific example of this invention, the behavior of the flexible thin plate member when a thermal load is applied to the flexible thin plate member wound around the cooling mechanism having the gas release mechanism is schematically shown. It is sectional drawing. It is an enlarged view of the dashed-dotted line part of FIG. It is a perspective view which shows a mode that the knurling process is given to the elongate flexible thin plate member.

  Hereinafter, a specific example of the film forming method of the present invention will be described in detail with reference to the drawings. First, referring to FIG. 1, as an example of a processing apparatus suitably used for the film forming method of the present invention, sputtering is applied to a long resin film F as a long flexible thin plate member. The vacuum film forming apparatus 50 that performs the film forming process will be described. The vacuum film forming apparatus 50 shown in FIG. 1 is an apparatus also called a sputtering web coater. When the film forming process is continuously and efficiently performed on the surface of the long resin film F transported by a roll-to-roll method. Preferably used.

More specifically, the vacuum film forming apparatus (sputtering web coater) 50 has a configuration in which various rolls and film forming means, which will be described later, are accommodated in a vacuum chamber 51. Various vacuum generating means such as a turbo molecular pump and a cryocoil are provided. By these vacuum generation means, pressure reduction of about 0.1 to 10 Pa is performed for sputtering film formation by reducing the pressure to an ultimate pressure of about 10 ⁻⁴ Pa and then introducing a sputtering gas. A known inert gas such as argon is used as the sputtering gas, and a gas such as oxygen is further added depending on the purpose. The shape and material of the vacuum chamber 51 are not particularly limited as long as they can withstand such a reduced pressure state, and various types can be used.

  In the vacuum chamber 51, various rolls are disposed that demarcate the transport path of the long resin film F that is transported by roll-to-roll from the unwind roll 52 to the take-up roll 64 through the can roll 56. In the conveyance path from the unwinding roll 52 to the can roll 56, a free roll 53 for guiding the long resin film F, a tension sensor roll 54 for measuring the tension of the long resin film F, and immediately upstream of the can roll 56. A motor-driven feed roll 55 provided on the side is arranged in this order. The feed roll 55 is adjusted with respect to the peripheral speed of the can roll 56, and the long resin film F fed from the tension sensor roll 54 toward the can roll 56 can be brought into close contact with the outer peripheral surface of the can roll 56.

  Similarly to the above, the conveyance path from the can roll 56 to the take-up roll 64 is a motor-driven feed roll 61 that adjusts the peripheral speed of the can roll 56, and a tension sensor roll 62 that measures the tension of the long resin film F. And the free roll 63 which guides the elongate resin film F is arrange | positioned in this order. In the unwinding roll 52 and the winding roll 64, the tension balance of the long resin film F is maintained by torque control using a powder clutch or the like.

  Of the outer peripheral surface of the can roll 56, the position facing the transport path of the long resin film F around which the long resin film F is wound (that is, the region in the angle range A in FIG. 1, also referred to as a holding angle), Magnetron sputtering cathodes 57, 58, 59 and 60 as film forming means are provided in this order along the transport path. Each of the magnetron sputtering cathodes 57 to 60 is provided with a plate-like target on the surface facing the outer peripheral surface of the can roll 56.

  Note that nodule (growth of foreign matter) may occur in the plate-like target. If this becomes a problem, a cylindrical rotary target with no use of nodule and high target use efficiency may be used. Good. Further, since the vacuum film-forming apparatus 50 in FIG. 1 is assumed to be a sputtering process as a process that requires a thermal load, the magnetron sputtering cathodes 57 to 60 are illustrated. In the case of other things such as chemical vapor deposition) or vapor deposition, these other vacuum film forming means are provided.

  The can roll 56 is constituted by a cylindrical member 10 as shown in FIG. 2, for example, and is driven to rotate about a rotation center axis 56a by a driving device (not shown). A conveyance path for conveying the long resin film F around the outer peripheral surface of the cylindrical member 10 is defined. In the inner part of the cylindrical member 10, a refrigerant circulation portion 11 through which a refrigerant such as cooling water flows is formed in a jacket structure, for example.

  The rotating shaft 12 located at the rotation center shaft 56a portion of the cylindrical member 10 has a double piping structure, and a refrigerant cooling device and a refrigerant circulating portion (not shown) provided outside the vacuum chamber 51 via the rotating shaft 12. The refrigerant circulates between the temperature and the temperature of the outer peripheral surface of the can roll. That is, the refrigerant cooled by the refrigerant cooling device is sent to the refrigerant circulation section 11 through the inner flow path of the inner pipe 12a, where the heat of the long resin film F is received and heated, and then the inner pipe 12a and It returns to the refrigerant cooling device again through the flow path between the outer pipe 12b. A bearing 13 that supports the rotating can roll 56 is provided outside the outer pipe 12b.

  A plurality of gas flow paths 14 extending in the direction of the rotation center axis 56a are disposed on the outer peripheral thick portion of the cylindrical member 10 of the can roll 56 over the entire circumference at substantially equal intervals in the circumferential direction. ing. Each gas flow path 14 has a gas discharge hole group 15 that opens on the outer peripheral surface side of the cylindrical member 10 (that is, on the outer peripheral surface side of the can roll 56). The gas discharge hole group 15 communicating with each gas flow path 14 is formed with substantially equal intervals along the extending direction of the gas flow path 14. A gas is supplied to each gas flow path 14 from the outside of the vacuum chamber 51 through a rotary joint described later, whereby the above-described region of the angle range A on the outer peripheral surface of the can roll 56 and the gas flow path 14 can be obtained. It becomes possible to introduce gas into a gap part (gap) formed between the long resin film F wound around the film.

  The number of gas flow paths 14, the number of gas discharge holes 15 communicating with each gas flow path 14, and the inner diameter thereof depend on the angle range A, the amount of gas introduced into the gap portion, the capacity of the exhaust pump of the vacuum chamber 51, and the like. As appropriate. Generally, it is better to provide a large number of gas discharge holes 15 with the smallest possible inner diameter across the entire area of the conveyance path excluding both ends in the width direction on the outer peripheral surface of the can roll. This is preferable in that it can be made uniform. However, since a processing technique for providing a large number of holes having a very small inner diameter at a narrow pitch is difficult, gas discharge holes 15 having an inner diameter of preferably 30 μm to 500 μm, more preferably an inner diameter of about 150 to 300 μm are provided in the circumferential direction and the width direction by 5 to 10 mm. It is preferable to provide the entire surface of the outer peripheral surface of the can roll 56 at a pitch except for both ends in the width direction.

  The rotary joint 20 interposed between the plurality of gas flow paths 14 and a gas supply source (not shown) outside the vacuum chamber 51 has, for example, a structure as shown in FIGS. More specifically, the rotary joint 20 includes a pair of rotating ring units 21 and a fixed ring unit 22. The rotating ring unit 21 is attached to one side of the cylindrical member 10 described above and rotates together with the cylindrical member 10. On the other hand, the fixing ring unit 22 is supported so as not to move in the vacuum chamber 51. The rotating ring unit 21 and the fixed ring unit 22 have sliding contact surfaces 21a and 22a at portions facing each other. When the rotating ring unit 21 rotates together with the cylindrical member 10, the sliding contact surfaces 21a and 22a. They are in sliding contact (sliding) with each other.

  In the rotating ring unit 21, the same number of gas supply passages 23 as the number of the gas passages 14 are formed over the entire circumference at equal intervals in the circumferential direction. Each of the plurality of gas supply paths 23 is formed radially inside the rotary ring unit 21 and / or parallel to the rotation axis direction of the rotary ring unit 21. One opening of each gas supply path 23 communicates with the gas flow path 14 at the same angular position as the gas supply path 23 via a connecting pipe 25, and the other opening is the gas supply path 23. Is opened as a rotary opening 23a at the sliding contact surface 21a having the same positional relationship as the angular position of the gas flow path 14 in communication therewith. Note that the gas supply path 23 and the gas flow path 14 may be directly communicated with each other without using the connection pipe 25.

  On the other hand, one gas distribution path 24 is formed in the fixed ring unit 22. One opening of the gas distribution path 24 is connected to a gas supply pipe 26 that supplies a gas from a gas supply source (not shown) outside the vacuum chamber 51, and the other opening is a slide of the fixed ring unit 22. The contact surface 22a opens as a fixed opening 24a. The fixed opening 24a is opposed to the rotation opening 23a of the gas supply path 23 communicating with the gas flow path 14 positioned within the angle range around which the long resin film F is wound. It is formed so as not to face the rotation opening 23a of the gas supply path 23 communicating with the gas flow path 14 located within the angular range where it cannot be wound.

  That is, the fixed opening 24a opens only within the angle range A in FIG. 1 where the long resin film F is wound, in the region on the sliding contact surface 22a of the fixed ring unit 22 that the rotation opening 23a can face. ing. Therefore, the shape of the fixed opening 24a of the gas distribution path 24 is such that the letter “C” is rotated 90 ° counterclockwise when viewed from the direction perpendicular to the sliding contact surface 22a. As a result, the rotary joint 20 is located from the outside of the vacuum chamber 51 when the rotary joint 20 is positioned within the angle range A of FIG. 1 with respect to each of the plurality of gas flow paths 14 rotated by the rotation of the cylindrical member 10. It can be controlled not to supply the gas supplied from the outside of the vacuum chamber 51 when the supplied gas is supplied and is located within the range of the angle range B of FIG.

  As a result, it is possible to prevent gas from leaking into the vacuum chamber 51 from the gas discharge hole group 15 located in the region of the angle range B on the outer peripheral surface of the can roll 56 and to wrap around the region of the angle range A. The gas can be satisfactorily introduced into the gap formed by the long resin film F and the outer peripheral surface. Thereby, the heat transfer coefficient in the said gap can be improved and the long resin film F can be effectively cooled.

  By the way, gas is generated between the outer peripheral surface of the cylindrical member 10 and the long resin film F wound around the outer peripheral surface of the cylindrical member 10 by the gas pressure of the gas discharged from the gas discharge hole group 15 using the vacuum film forming apparatus having the above-described configuration. Even when the filled gap is formed, the gas pressure at both ends in the width direction of the long resin film F tends to be low, and the both ends may come into contact with the outer surface of the cylindrical member 10. As a result, as shown in FIG. 4, even if a force is applied to the film due to a thermal load during film formation or the like, deformation of the film is constrained by friction between both ends of the film and the outer peripheral surface of the can roll. The film thermally expanded non-uniformly, the gap interval increased, and the cooling efficiency further decreased, and wrinkles were sometimes generated. Therefore, in the film forming method of one specific example of the present invention, as shown in FIG. 5, a plurality of protrusions projecting toward the outer peripheral surface of the cylindrical member 10 along the longitudinal direction at both ends in the width direction of the long resin film F. The minute convex part P is provided.

  Thus, by providing a plurality of minute convex portions P at both ends in the width direction of the long resin film F, both end portions in the width direction of the long resin film F can easily come into contact with the outer peripheral surface of the cylindrical member 10. However, since it is limited to the convex part P even if it contacts, compared with the case of the above-mentioned conventional film-forming method, the contact area of the elongate resin film F can be reduced significantly. As a result, when a heat load is applied to the long resin film F and a force to deform in the width direction is applied, the frictional force with the outer peripheral surface of the cylindrical member 10 is greatly reduced. As shown in FIG. 6, it can be deformed relatively freely in the width direction without being constrained. Therefore, the gap interval can be made substantially uniform in the width direction of the long resin film F. And since the gas discharge | released from the gas discharge hole group 15 is satisfy | filled in the gap formed between the outer peripheral surface of the cylindrical member 10, and the elongate resin film F wound around there, the cylindrical member 10 The cooling efficiency can be increased substantially uniformly over the entire surface of the long resin film F wound around the outer peripheral surface.

  Further, even if non-uniform thermal expansion occurs in the long resin film F due to the local thermal load of sputtering, the outer side of the cylindrical member 10 is caused by relatively free deformation in the width direction of the long resin film F described above. The variation in the gap distance between the surface and the long resin film F in the width direction is mitigated, so that the cooling efficiency is homogenized in the width direction, so that uneven thermal expansion chains are less likely to occur and wrinkles are generated. Is not reached.

  Each of the plurality of minute projections P described above preferably has a shape in which the long resin film F is locally lifted so as to bend the ridge, and the plurality of minute projections P Are preferably formed on the long resin film F so as to be separated from each other. Thereby, contact with the outer peripheral surface of the cylindrical member 10 of each convex part P becomes point contact, and the gas introduced into the gap from the gas discharge hole group 15 is adjacent convex parts at both ends of the long resin film F. Since it discharge | releases moderately from between P, the distance of the gap between the elongate resin film F and the outer peripheral surface of the cylindrical member 10 is stabilized. The film formation on the long resin film F may be performed not only on one side but also on both sides. Thus, when forming into a film on both surfaces, the both ends of the elongate resin film F are provided with a plurality of minute protrusions protruding toward one surface and a plurality of minute protrusions protruding toward the other surface. Is preferably formed alternately in the longitudinal direction.

  The step (height) of the minute projections P formed at both ends of the long resin film F is ½ or more of the thickness of the long resin film F, and the gas supplied from the gas discharge hole group 15. It is preferable that the average free path of the seed is not more than twice. If the level difference of the convex portion P is less than ½ of the thickness of the long resin film F, the gap between the outer peripheral surface of the cylindrical member 10 and the long resin film F is caused by the gas pressure of the gas supplied from the gas discharge hole group 15. Even if the gap is formed, the place other than the convex portion P of the long resin film F may come into contact with the outer peripheral surface of the cylindrical member 10.

  On the other hand, if the level difference of the convex part P exceeds twice the mean free path of the gas species supplied from the gas discharge hole group 15, it is between the adjacent minute convex parts P at both ends of the long resin film F. Gas in the gap is easily released, the gap distance is not stabilized, and the long resin film F comes into contact with the outer peripheral surface of the cylindrical member 10 to change the cooling efficiency, which may cause wrinkles. In this case, as the physical properties of the gas used for calculating the mean free path, the physical properties of the gas flowing in the gas supply pipe 26 can be used.

  The minute projections P formed at both ends of the long resin film F can be formed by knurling (also referred to as knurling or embossing) as shown in FIG. 7, for example. That is, a pair of rollers 30a, 30b each having a concave portion and a convex portion formed on the corresponding outer peripheral surface are rotated in opposite directions, and the end portion of the long resin film F is sandwiched between the outer peripheral surfaces to locally Thus, the convex portion P having a shape that is lifted up can be continuously formed. FIG. 7 shows a case where both ends of the long resin film F are sandwiched between two pairs of rollers 30a and 30b.

  The vacuum film forming apparatus 50 shown in FIG. 1 is generally provided with a deposition plate or the like in order to prevent film formation on, for example, both ends other than the conveyance path on the outer peripheral surface of the cylindrical member 10. Limiting is done. For this reason, both ends in the width direction of the long resin film F tend to have a smaller amount of film formation than the center, and therefore both ends are often non-deposition regions. Therefore, it is preferable to form the minute projections P at both ends in the width direction of the long resin film F in this non-film formation region.

  In order to perform cooling appropriately with the gas interposed between the long resin film F and the outer peripheral surface of the cylindrical member 10, it is desirable to set the gap interval so that the gas can be handled with a molecular flow. The distance, that is, the separation distance between the outer peripheral surface of the cylindrical member 10 and the long resin film F facing it, is preferably 3 times or less of the mean free path of the molecules of the gas species present therein. If this distance exceeds 3 times the mean free path of the molecules of the intervening gas species, the cooling efficiency is lowered, and the long resin film F may thermally expand due to heat load, and wrinkles may occur.

  In order to obtain the gap distance, it is necessary to supply the gas at a pressure sufficient to resist at least the force to press the long resin film F against the outer peripheral surface of the cylindrical member 10. The force to press the long resin film F against the outer peripheral surface of the cylindrical member 10 is proportional to the tension applied to the long resin film F, and the radius of the cylindrical member 10 of the can roll and the width of the long resin film F Inversely proportional to Accordingly, the pressure of the gas supplied to the gas discharge hole group 15 is appropriately adjusted so that the gas pressure interposed between the long resin film F and the outer peripheral surface of the can roll can counter the force determined by these parameters. .

  Inert argon gas used for normal vacuum film formation has an average free path of about 50 μm when the gas pressure is about 500 Pa. Therefore, an argon gas having a gas pressure of about 500 Pa is set to a gas flow rate or a supply gas pressure, for example. Introducing into the gap part while adjusting, the gap between the gap parts is controlled to 150 μm or less, and effective cooling becomes possible. Generally, if the gas pressure to be introduced is within a range of 10 to 1000 Pa, the gap amount can be set. As described above, the gas introduced into the gas discharge hole group 15 is preferably the same as the sputtering gas. This is because the sputtering atmosphere is not contaminated by using the same sputtering gas. In addition, the gap | interval of a gap part can be measured with a laser displacement meter etc.

  When producing a resin film with a metal film using the film forming method of the present invention, the long resin film F includes a heat resistant resin film such as a polyimide film or a liquid crystal polymer film, or a polyethylene terephthalate (PET) film. Such a resin film is used. Examples of the metal film to be formed include a structure in which a film made of a Ni-based alloy or the like and a Cu film are stacked. This resin film with a metal film is obtained by forming a metal film on at least one surface of the long resin film F, and no adhesive is interposed between the metal film and the long resin film F. The resin film with a metal film having such a structure can be processed into a flexible wiring board by, for example, a subtractive method. Here, the subtractive method is a method of forming an electric circuit by removing a metal film (for example, the Cu film) not covered with a resist having a circuit pattern by etching.

  The film made of Ni alloy or the like is called a seed layer, and various known alloys such as Ni-Cr alloy, Inconel, Constantan, Monel, etc. can be used. It is selected according to desired characteristics such as migration resistance. Moreover, when it is desired to make the metal film of the resin film with a metal film thicker, the metal film may be laminated using a wet plating method. That is, there are a case where a metal film is laminated only by electroplating treatment, and a case where electroless plating treatment is performed as primary plating and wet plating methods such as electrolytic plating treatment are combined as secondary plating. The wet plating process may employ various conditions of a conventional wet plating method.

  As described above, the film forming method of the present invention has been described by taking as an example the case where sputtering is performed on a long resin film as a flexible thin film member. However, the present invention is not limited to a metal thin plate that can be conveyed by a roll-to-roll method. The present invention can also be applied to foils, flexible glassy substrates, and the like. In addition to sputtering, the film forming method can also be applied to ion plating, vacuum deposition, chemical vapor deposition (CVD), and the like.

Example 1
By a knurling process using two pairs of rollers as shown in FIG. 7, a plurality of convex portions P having a step of 50 μm are arranged in two rows at equal intervals along the longitudinal direction at both ends in the width direction of a 25 μm-long polyimide film. A sputtering web coater as shown in FIG. 1 was used for this film to form a copper sputtering film. In addition, the some convex part P was formed so that it might protrude toward this outer peripheral surface, when wound around the outer peripheral surface of the can roll 56 of FIG.

  The sputtering gas and the gas species released from the gas discharge hole group 15 are argon, the pressure in the vacuum chamber 51 is 0.3 Pa, the gas pressure of the gas supplied to the gas discharge hole group 15 is 500 Pa, and the thickness of the copper layer is 100 nm. The dynamic film formation rate is 1000 nm · m / min. It was. The average free path of the argon gas having a gas pressure of 500 Pa is 50 μm. When the polyimide film was visually confirmed after the completion of sputtering, no wrinkles were generated.

(Example 2)
A copper sputtering film was formed under the same conditions as in Example 1 except that a long polyimide film having a thickness of 12.5 μm was used instead of the thickness of 25 μm. When the polyimide film was visually confirmed after the completion of sputtering, no wrinkles were generated.

(Example 3)
Copper sputtering film-forming was performed on the same conditions as Example 1 except having formed the convex part P with a level | step difference of 200 micrometers in the width direction both ends of a long polyimide film. As a result, there were several small wrinkles that would not be a problem. This is because the convex step 200 μm is about four times the mean free path of the supplied 500 Pa argon gas, so the gas intervening in the gap between the outer surface of the can roll and the polyimide film is polyimide. It is considered that the pressure is easily released from both ends in the width direction of the film, the pressure in the gap portion decreases, and the polyimide film locally contacts the outer peripheral surface of the can roll.

(Comparative example)
A copper film was formed by sputtering under the same conditions as in Example 2 except that the convex portions were not formed at both ends of the long polyimide film. As a result, significant wrinkles occurred during film formation. This is because both ends of the polyimide film in the width direction contacted the outer peripheral surface of the can roll, and deformation due to thermal expansion was restrained, so the polyimide film locally contacted the outer peripheral surface of the can roll in a deformed state. It is thought to be due to.

DESCRIPTION OF SYMBOLS 10 Cylindrical member 11 Refrigerant circulation part 12 Rotating shaft 13 Bearing 14 Gas flow path 15 Gas discharge hole group 20 Rotary joint 21 Rotating ring unit 22 Fixed ring unit 23 Gas supply path 24 Gas distribution path 25 Connection pipe 26 Supply pipe 50 Vacuum film formation Equipment (Sputtering web coater)
51 Vacuum Chamber 52 Unwinding Roll 53, 63 Free Roll 54, 62 Tension Sensor Roll 55, 61 Feed Roll 56 Can Roll 57, 58, 59, 60 Magnetron Sputtering Cathode 64 Winding Roll F Long Resin Film P Convex

Claims (9)

A plurality of gas passages in the outer peripheral thick portion and gas discharge hole groups opening along the extending direction of the gas passages on the outer peripheral surface side from each of the gas circulation holes are provided in the outer peripheral wall portion. A long flexible thin plate member that is conveyed in a roll-to-roll manner under reduced pressure is wound around the outer peripheral surface of a cylindrical cooling mechanism that is disposed over the entire circumference with a space therebetween, and the back side thereof A film forming method of a flexible thin plate member for forming a thin film on the surface side while cooling from
The flexible thin plate member wound around the outer peripheral surface has a plurality of convex portions protruding along the longitudinal direction at both end portions in the width direction, and projecting toward the outer peripheral surface. A method for forming a thin plate member.   Each of the plurality of convex portions has a shape in which the flexible thin plate member is locally lifted, the height thereof is ½ or more of the thickness of the flexible thin plate member, and the gas discharge hole group The film forming method for a flexible thin plate member according to claim 1, wherein the average free path of the gas released from the gas is 2 times or less.   When the flexible thin plate member is wound around the outer peripheral surface of the cooling mechanism, the flexible thin plate member is brought into point contact with the outer peripheral surface at the top of each of the plurality of convex portions, and the exception portion is separated from the outer peripheral surface. The method for forming a flexible thin plate member according to claim 1 or 2.   4. The method for forming a flexible thin plate member according to claim 3, wherein the distance to be separated is set to be within three times the mean free path of the gas released from the gas discharge hole group.   The method for forming a flexible thin plate member according to claim 4, wherein a gas having a gas pressure of 10 to 1000 Pa is discharged from the gas discharge hole group.   The film forming method for a flexible thin plate member according to claim 1, wherein the plurality of convex portions are formed in a region where the film is not formed on the flexible thin plate member.   The film forming method for a flexible thin plate member according to claim 1, wherein the plurality of convex portions are formed by knurling.   The flexible thin plate member further includes a plurality of protrusions protruding in a longitudinal direction at both end portions in the width direction, the protrusions protruding in a direction away from the outer peripheral surface. The film-forming method of the flexible thin plate member of any one of 1-7.   The flexible thin plate member is a long resin film, and is formed on at least one surface of the long resin film by using the method for forming a flexible thin plate member according to claim 1. A method for producing a resin film with a metal film, wherein a metal film is formed without using an adhesive.

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