Resin surface hydrophilization method, plasma processing device, laminated body and preparation method of laminated body

Abstract

Provided is a laminate in which a resin substrate and a metal vapor-deposited film are firmly adhered to each other. A method for manufacturing a laminate includes a detachment step (S10), an introduction step (S20), a vapor deposition step (S30), and a coating step (S40). In the detachment step (S10), the hydrophobic surface of the resin is irradiated with plasma, and at least some of the atoms constituting the resin are detached from the surface. In the introduction step (S20), the surface of the resin that has passed through the detachment step (S10) is irradiated with hydroxyl radicals, and a hydrocarbon group is introduced into the surface of the resin. In the vapor deposition step (S30), a metal film is deposited on the surface of the resin that has passed through the introduction step (S20). In the coating step (S40), the surface of the metal film is coated with a metal layer comprising a metal that is the same as the metal constituting the metal film.

Description

[0001] The present invention is a divisional application with an application date of August 6, 2020, an application number of 202080036436.X, and an invention name of “A method for hydrophilizing a resin surface, a plasma treatment device, a laminate, and a method for preparing a laminate”. Technical Field

[0002] The present application relates to a resin surface hydrophilization method, a plasma treatment device, a laminate and a method for preparing the laminate, which are compatible with millimeter waves or microwaves and suitable for manufacturing circuit boards with low transmission losses. Background Art

[0003] As the substrate of the circuit board, fluororesins such as low dielectric liquid crystal polymer (LCP: Liquid Crystal Polymer) or polytetrafluoroethylene (PTFE) have begun to be used instead of traditional polyimide. LCP or PTFE has the problem of poor adhesion with copper used as wiring materials. For this reason, the physical adhesion between the substrate and copper is improved by chemically roughening the surface of the substrate of the circuit board or forming concave and convex surfaces of the copper foil that is closely attached to the substrate.

[0004] When the surface of substrate is chemically roughened, and when copper is formed on the substrate surface, due to the roughness of the surface of substrate, the transmission loss of circuit board can become larger. When copper is attached to the substrate surface using adhesive, the adhesive layer itself can cause the transmission loss of circuit board. When copper is formed on the substrate surface by plating, the closeness between substrate and copper can not be fully obtained. In addition, there is a method for obtaining a laminate of PTFE substrate and copper, which is activated by irradiating atmospheric plasma to the PTFE substrate, and the fluorine in the PTFE substrate is replaced by the hydroxyl from the moisture in the air, so that copper and the PTFE substrate surface are close.

[0005] However, even if the PTFE substrate is irradiated with atmospheric plasma, the contact angle of the PTFE substrate and water is about 50 °. And, when the surface of copper and the PTFE substrate are made to fit, the fit of the PTFE substrate and copper is about 0.4N / mm. Therefore, in the process of making the circuit pattern of copper on the PTFE substrate, copper may be peeled off from the PTFE substrate. In addition, when the PTFE substrate is heated in the manufacturing process of the circuit pattern, the fit between the PTFE substrate and the copper can be further reduced. In addition, the time that the PTFE substrate surface is modified is about 24 hours, and it is necessary to make copper and the PTFE substrate surface fit as soon as possible quickly, which becomes the restriction of circuit board manufacturing.

[0006] In Patent Document 1, the surface of the substrate is cleaned with a high energy beam in a vacuum, and then the surface of the substrate is irradiated with ionized water vapor to adsorb hydroxyl groups on the surface of the substrate. However, since the energy of the ionized water vapor is very strong, when other water vapor ions are irradiated onto the surface of the substrate, the temporarily adsorbed hydroxyl groups will be detached from the surface of the substrate again. Therefore, the contact angle between the substrate surface and water is about 40°.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 9-3220 Summary of the invention

[0010] Technical problem to be solved by the invention

[0011] The present application is proposed in view of such a situation, and its purpose is to provide a resin surface hydrophilization method for imparting high hydrophilicity to the hydrophobic surface of the resin for a long time, a plasma treatment device that can implement the resin surface hydrophilization method, a method for manufacturing a laminate using the resin surface hydrophilization method, and a laminate obtained by, for example, the manufacturing method of the laminate.

[0012] Means for solving technical problems

[0013] The resin surface hydrophilization method of the present application includes: a detachment step, irradiating the hydrophobic surface of the resin with plasma to detach at least a part of the atoms constituting the resin from the surface; and an introduction step, irradiating hydroxyl radicals on the resin surface that has undergone the detachment step to introduce hydrocarbon groups into the resin surface.

[0014] The manufacturing method of the laminated body of the present application includes: a detachment step, irradiating the hydrophobic surface of the resin with plasma to detach at least a part of the atoms constituting the resin from the surface; an introduction step, irradiating the surface of the resin that has undergone the detachment step with hydroxyl radicals to introduce hydrocarbon groups into the resin surface; and a vapor deposition step, vapor depositing a metal film on the surface of the resin that has undergone the introduction step.

[0015] The plasma processing device of the present application includes a first processing device and a second processing device, wherein the first processing device has: a first chamber; a first holding portion for holding a resin; a first gas introduction portion for introducing a first gas into the first chamber, wherein when the first gas is plasmatized, at least a portion of atoms constituting the resin is separated from the surface of the resin; a first plasma generating portion for plasmatizing the first gas; the second processing device has: a second chamber; a second holding portion for holding the resin processed by the first chamber and applied with a first DC voltage; a second gas introduction portion for introducing a second gas into the second chamber, wherein the second gas is plasmatized to generate hydroxyl radicals; and a second plasma generating portion for plasmatizing the second gas and applied with a second DC voltage higher than the first DC voltage.

[0016] The laminate of the present application comprises: a resin substrate, in which a part of the atoms existing on the hydrophobic surface of the resin is substituted by hydroxyl groups; a metal vapor-deposited film formed on the surface of the resin substrate; and a contact angle between the surface of the resin substrate and water of less than 30°.

[0017] Effects of the Invention

[0018] According to the resin surface hydrophilization method of the present application, high hydrophilicity can be given to the hydrophobic surface of the resin for a long time. Therefore, it is easy to form a metal film on the surface of the resin. According to the manufacturing method of the laminated body of the present application, a laminated body in which the resin substrate and the metal vapor-deposited film are firmly and closely bonded can be obtained. According to the plasma treatment device of the present application, the resin surface hydrophilization method of the present application can be easily implemented. In the laminated body of the present application, the resin substrate and the metal vapor-deposited film are closely bonded to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a flow chart of a method for manufacturing a laminate.

[0020] Figure 2 It is a schematic cross-sectional view showing the basic structure of the processing device.

[0021] Figure 3 It is a schematic cross-sectional view of the plasma processing apparatus according to the first embodiment.

[0022] Figure 4 It is a schematic cross-sectional view of a plasma processing apparatus according to a second embodiment.

[0023] Figure 5 It is a schematic cross-sectional view of a plasma processing apparatus according to a third embodiment.

[0024] Figure 6 It is a schematic vertical cross-sectional view of a plasma processing apparatus according to a fourth embodiment.

[0025] Figure 7 It is a schematic horizontal cross-sectional view of a plasma processing apparatus according to a fourth embodiment.

[0026] Figure 8 These are images of water dripping on the substrate surface before and after the treatment in the example and SEM images of the substrate surface.

[0027] Fig. 9 This is a graph showing the measurement results of the contact angle between the surface of the substrate after the treatment in Examples and water. DETAILED DESCRIPTION

[0028] In order to apply the resin to electronic substrates and the like, the hydrophobic surface of the resin needs to be hydrophilized. Figure 1 It is a flow chart of each step of the manufacturing method of the laminated body of the present application. In the manufacturing method of the laminated body, the first two steps are methods for hydrophilizing the resin surface. That is, the resin surface hydrophilizing method of the embodiment of the present application includes a detachment step S10 and an introduction step S20. In the detachment step S10, the hydrophobic surface of the resin is irradiated with plasma to detach at least a part of the atoms constituting the resin from the resin surface. That is, in the detachment step S10, the hydrophobic surface of the resin is washed with plasma, especially with ions in the plasma, to activate the resin surface.

[0029] As resin, there is no particular limitation, as long as it has a hydrophobic surface, fluorine-containing resins such as PTFE, polyimide or LCP can be exemplified. Preferably, the resin contains fluorine and carbon, and the atoms detached from the hydrophobic surface of the resin are fluorine and carbon. This is because the hydrophobic surface of the resin is greatly hydrophilized. In addition, it is excellent as an electrical substrate because of its high insulation properties of fluorine-containing resins. Optionally, the resin contains a wholly aromatic polyester, and the atoms detached from the hydrophobic surface of the resin are oxygen. The plasma particularly preferably contains at least one of nitrogen and argon. This is because, through the ions of nitrogen or argon, the atoms constituting the resin can easily detach from the resin surface.

[0030] In the introduction step S20, the surface of the resin that has passed the separation step S10 is irradiated with hydroxyl radicals to introduce hydrocarbon groups (-OH) into the resin surface. The hydrophilicity of the resin surface into which hydroxyl groups have been introduced is high. For example, water vapor is plasmatized, and the hydroxyl radicals in the plasma are irradiated onto the surface of the resin that has passed the separation step S10. It is preferred that the separation step S10 and the introduction step S20 are performed under reduced pressure, and after the separation step S10, the introduction step S20 is performed while maintaining the reduced pressure. This is because, in the separation step S10, hydroxyl groups can be introduced into the resin surface while maintaining the resin surface in an activated state. In addition, the surface of the resin that has passed the introduction step S20 can maintain hydrophilicity for a long time, for example, for more than one month. Therefore, there is no problem even if the resin is released into the atmosphere after the introduction step S20.

[0031] Preferably, the detachment step S10 is performed at a first pressure of 0.1 Pa or more and 0.4 Pa or less, and the introduction step is performed at a second pressure, which is 30% or more and 50% or less of the first pressure. This is because, in the detachment step S10, it is easy to control the advancing direction of ions and radicals in the plasma, and in the introduction step S20, hydroxyl radicals become easy to irradiate the resin surface, but ions hardly irradiate the resin surface. The introduction step is preferably performed at a temperature of the resin of 150° C. or more and 300° C. or less. This is because the chemical reaction between the hydroxyl group and the resin surface is promoted, and the hydroxyl group is firmly introduced to the resin surface.

[0032] When the resin obtained by the resin surface hydrophilization method so far is used for electronic substrates, it is desired to attach a metal, such as copper, to the resin surface. Therefore, plasma, ions or free radicals are irradiated on the metal target, and the metal released from the metal target is thinly evaporated on the resin surface. That is, the manufacturing method of the laminate of the present application includes a detachment step S10, an introduction step S20 and a vapor deposition step S30. That is, the manufacturing method of the laminate of the present application is provided with a vapor deposition step S30 after the resin surface hydrophilization method of the present application. Since the detachment step S10 and the introduction step S20 are the same as the steps in the resin surface hydrophilization method of the present application, the description of the detachment step S10 and the introduction step S20 will be omitted.

[0033] In the evaporation step S30, a metal film is evaporated on the surface of the resin after the introduction step S20. The metal film is evaporated, for example, by a CVD method or a PVD method (sputtering). Examples of the metal film include a copper film, a silver film, and a gold film. In the evaporation step, the resin released into the atmosphere after the introduction step S20 can be used. However, in order to improve productivity and prevent various pollutants from adhering to the resin, it is preferred to perform the introduction step S20 and the evaporation step S30 while maintaining a reduced pressure state.

[0034] The surface of the vapor-deposited metal film can be easily plated or hot-pressed with the same metal. That is, the method for manufacturing the laminate of the present application may further include a coating step S40 after the vapor deposition step S30. In the coating step S40, a metal layer composed of a metal that is the same as the metal constituting the metal film is further coated on the surface of the metal film obtained by vapor deposition. As a method for coating the metal layer on the surface of the metal film, there can be exemplified a method of overlapping the metal film of the laminate after the vapor deposition step S30 and the metal layer and performing hot pressing; or a method of forming a metal layer by plating on the metal film of the laminate after the vapor deposition step S30.

[0035] The laminate of the embodiment of the present application includes a resin substrate, in which a part of the atoms existing on the hydrophobic surface of the resin is substituted by hydroxyl groups; and a metal vapor-deposited film, which is formed on the surface of the resin substrate. In addition, the contact angle between the surface of the resin substrate and water is less than 30°. Therefore, the surface of the resin substrate is firmly in contact with the metal vapor-deposited film. The contact angle between the surface of the resin substrate and water is more preferably less than 10°. In the laminate of the present application, a metal layer composed of a metal can be provided on the surface of the metal vapor-deposited film, and the metal is the same as the metal constituting the metal vapor-deposited film. Optionally, the resin is polytetrafluoroethylene, and the atom substituted by the hydroxyl group is fluorine. In addition, optionally, the resin is a liquid crystal polymer containing a wholly aromatic polyester.

[0036] Figure 2 The basic structure of a treatment device 80 that can be used in the resin surface hydrophilization method of the present application is shown. The treatment device 80 includes a vacuum chamber 2, a fine plasma gun (FPG) 3 as a "plasma irradiation source", a holding table 4, a cover 5, a first DC power supply 9 and a second DC power supply 8. The vacuum chamber 2 is made of a metal such as an aluminum alloy or stainless steel, and is connected to a ground 10. The FPG 3 is arranged at the upper part of the vacuum chamber 2. The FPG 3 plasmatizes the treatment gas introduced into the vacuum chamber 2 from the gas introduction part (not shown).

[0037] FPG3 can adopt the article described in International Publication No. 2014 / 175702, for example. The holding table 4 is arranged below FPG3 and is opposite to FPG3. The holding table 4 is made of metal or an electrode, and holds the treated component 1. The cover 5 covers the upper surface of the holding table 4. The cover 5 is made of the same material as the treated component 1 to uniformly irradiate plasma from FPG3 to the treated component 1. The first DC power supply 9 is connected to the holding table 4. The second DC power supply 8 is connected to FPG3.

[0038] While depressurizing the vacuum chamber 2 with an exhaust pump (not shown), a processing gas such as nitrogen, argon, oxygen or water vapor is introduced into the vacuum chamber 2 from the gas introduction portion, and the vacuum chamber 2 is adjusted to a predetermined pressure, for example, 0.3 Pa within a range of 0.1 Pa to 0.4 Pa. When a second DC voltage is applied from the second DC power supply 8 to the FPG 3 in this state, plasma of the processing gas is generated by the FPG 3.

[0039] At this time, if the pressure in the vacuum chamber 2 is too high, for example, when it exceeds 0.4 Pa, the processing gas enters a glow discharge state, and the traveling direction of the ions 7 and radicals 6 in the plasma cannot be controlled. On the other hand, if the pressure in the vacuum chamber 2 is within an appropriate range, the dark discharge state of the processing gas can be maintained, and the traveling direction of the ions 7 and radicals 6 can be controlled. Therefore, the pressure in the vacuum chamber 2 is adjusted to, for example, 0.1 Pa or more and 0.4 Pa or less.

[0040] When the detaching step S10 is performed using the processing device 80, the following steps are followed. First, the treated component 1 as a resin is held by the holding table 4, and nitrogen and / or argon as a processing gas is injected into the vacuum chamber 2 from the gas introduction part to adjust the pressure in the vacuum chamber 2 to 0.3 Pa, which is greater than 0.1 Pa and less than 0.4 Pa. Then, the second DC power supply 8 is turned on while the first DC power supply 9 is turned off, that is, while the holding table 4 is grounded.

[0041] The plasma of the processing gas is generated by FPG3, and directional ions and free radicals are irradiated to the processed component 1. Then, atoms are detached from the surface of the processed component 1 mainly by the impact of ions. Since ions and free radicals have directionality, atoms can be effectively detached from the surface of the processed component 1. In addition, most of the detached atoms are discharged to the outside of the vacuum chamber 2 by the exhaust pump. A part of the detached atoms is suspended in the vacuum chamber 2 or attached to the inner wall of the vacuum chamber 2 or the components in the vacuum chamber 2 after being suspended. However, in the present embodiment, since the pressure in the vacuum chamber 2 is lower than the general glow discharge condition, there are almost no impurities floating in the vacuum chamber 2. Therefore, the contamination of the processed component 1 is suppressed.

[0042] When the treatment device 80 is used to perform the detachment step S10, when the voltage of the second DC power supply 8 is increased, more plasma of the treatment gas is generated, and atoms are promoted to detach from the surface of the treated component 1. However, if the treatment is performed at a high voltage at one time, Figure 8 (b) The wrinkled wall seen in the photo grows too much and causes the unevenness to become larger. Large unevenness is not desired because it increases the transmission loss of the electronic substrate. In the present invention, the voltage of the second DC power supply 8 changes over time. Since unevenness will not be formed at the beginning of the detachment step, processing is performed by increasing the removal amount through high voltage. Processing by high voltage can remove the dirt attached to the surface of the processed component 1 at one time, so it is convenient. When wrinkles are formed and unevenness is generated, the voltage is reduced and gentle processing is performed to avoid deterioration of the surface roughness. Residual stress is generated on the surface by processing, but the residual stress can also be suppressed by gentle processing with reduced voltage in the second half of the process.

[0043] When the introduction step S20 is performed using the processing device 80, the following steps are followed. In addition, it is preferred that the detachment step S10 and the introduction step S20 are performed by respective processing devices 80. This is because if the introduction step S20 is performed using the same processing device 80 as the processing device 80 that performed the detachment step S10, that is, in the same processing device 80, when the introduction step S20 is performed after the detachment step S10, the components detached from the surface of the treated component 1 in the detachment step S10 will adhere to the vacuum chamber 2, and there is a possibility that the attached matter will be suspended and attached to the treated component 1 in the subsequent introduction step S20. If it is not affected by the suspended matter from the detachment step S10, the detachment step S10 and the introduction step S20 can be performed by the same processing device 80.

[0044] First, the treated component 1 that has undergone the separation step S10 is held on the holding table 4. Preferably, by setting a vacuum standby chamber or the like between the two treatment devices 80, the treated component 1 is transferred from the treatment device 80 that has performed the separation step S10 to the treatment device 80 that has performed the introduction step S20 without opening the atmosphere. Then, a treatment gas containing water and / or water vapor is introduced into the vacuum chamber 2 from the gas introduction part. The treatment gas is preferably water vapor. This is because hydroxyl radicals, which are free radicals 6, are easily generated.

[0045] Then, the pressure in the vacuum chamber 2 is adjusted by the exhaust pump so that the pressure in the vacuum chamber 2 is 30% or more and 50% or less of the pressure in the decoupling step S10. Since the pressure introduced into the step S20 is 30% or more and 50% or less of the pressure in the decoupling step S10, a large amount of hydroxyl radicals as radicals 6 are generated in the plasma of the processing gas. Then, the first DC power supply 9 and the second DC power supply 8 are turned on. The plasma of the processing gas is generated by the potential difference between the FPG 3 and the grounded vacuum chamber 2.

[0046] At this time, the voltage from the first DC power supply 9 is preferably smaller than the voltage from the second DC power supply 8, and more preferably 40% or more of the voltage from the second DC power supply 8, and smaller than the voltage from the second DC power supply 8. This is because by reducing the potential difference between FPG3 and the holding table 4, a large number of hydroxyl radicals as radicals 6 can be extracted from the plasma of the processing gas and irradiated to the processing component 1. That is, since the vacuum chamber 2 is grounded, the potential difference between FPG3 and the vacuum chamber 2 is greater than the potential difference between FPG3 and the holding table 4. Therefore, most of the ions 7 in the plasma of the processing gas move in the direction from FPG3 to the vacuum chamber 2, rather than in the direction from FPG3 to the holding table 4. The hydroxyl radicals as radicals 6 without polarity in the remaining plasma are irradiated to the processing component 1.

[0047] By irradiating the treated part 1 with hydroxyl radicals as free radicals 6, hydroxyl groups are introduced to the surface of the treated part 1. In addition, since the ions 7 are hardly irradiated to the treated part 1, it is possible to suppress the hydroxyl groups introduced to the surface of the treated part 1 from being separated again due to the impact of the ions. As described above, the surface of the treated part 1 is given stable hydrophilicity. By introducing the hydroxyl groups, the hydroxyl groups are chemically bonded to the surface of the treated part 1.

[0048] Figure 3 A schematic diagram of a plasma processing device 90 according to a first embodiment of the present application is shown. In the first embodiment, the component to be processed is a sheet-like resin. The plasma processing device 90 includes a first processing device 91 and a second processing device 92. The first processing device 91 for performing the separation step S10 includes a first chamber 25, a supply roller 11, first holding parts 14, 15, a first gas introduction part 17, a "first plasma generation part", and FPGs 12, 13 as "plasma irradiation sources".

[0049] The surface of the supply roller 11 is wound with a sheet-like resin having hydrophobicity, and the resin is supplied to the first holding parts 14 and 15 while rotating. The resin supplied from the supply roller 11 is held while being wound onto a part of the columnar first holding parts 14 and 15. The FPG 12 is arranged so as to be opposite to the first holding part 14. The FPG 13 is arranged so as to be opposite to the first holding part 15. By arranging the first holding parts 14 and 15 and the FPG 12 and 13 as described above, the separation step S10 can be performed on both surfaces of the resin in the first processing device 91. In addition, since two FPGs are provided with respect to one first holding part, the separation step S10 can be effectively performed.

[0050] The first gas introduction unit 17 introduces the first gas into the first chamber, and when the first gas is converted into plasma, at least a part of the atoms constituting the resin is separated from the surface of the resin. That is, when the first gas is converted into plasma, the directional ions and free radicals in the plasma act on the surface of the resin, so that at least a part of the atoms constituting the resin is separated from the surface of the resin. In the first embodiment, the first gas is nitrogen and / or argon.

[0051] The FPG 12 and 13 are applied with a voltage by a power source (not shown) to plasma-form the first gas. No voltage is applied to the first holding parts 14 and 15. That is, the first holding parts 14 and 15 are grounded. In addition, there is no particular limitation on the plasma generation method in the first plasma generating part. An AC voltage may be applied to the first plasma generating part to generate plasma. The pressure in the first chamber 25 is about 0.3 Pa that can maintain dark discharge.

[0052] In the detachment step S10, when the voltage of FPG12 and 13 is increased, more plasma of the processing gas is generated, and atoms are promoted to detach from the surface of the processed component 1. However, when processing is performed at a high voltage at one time, Figure 8 (b) The wrinkled wall seen in the photo grows too much and causes the unevenness to become larger. Large unevenness is not desirable because it will increase the transmission loss of the electronic substrate. In the present invention, the voltages applied to FPG12 and 13 are set based on the order in which the sheets of the processed component 1 are irradiated with plasma. Specifically, in each of the two FPGs of FPG12 and 13, a voltage difference is set between the voltage applied to the FPG to be irradiated first to the sheet of the processed component 1 and the FPG to be irradiated later. The voltages applied to FPG12 and 13 are set based on the order in which the processed component 1 is irradiated with plasma.

[0053] For example, in Figure 3 In the process, the sheet of the treated component 1 is first irradiated with plasma FPG12, 13 ( Figure 3 As for the FPG12 and 13 on the left side shown in the figure, since it is at the beginning of the separation step, no unevenness will be formed, so the voltage applied to the FPG12 is set to a high voltage. By processing with a high voltage, it is beneficial to remove the attached contaminants attached to the surface at one time, so it is advantageous. On the other hand, the FPG12 and 13 ( Figure 3 The FPGs 12 and 13 on the right side shown in the figure have wrinkles and unevenness, so by applying the FPGs 12 and 13 ( Figure 3 The FPG12 and 13 on the left shown in the figure can achieve gentle processing by lowering the voltage to avoid deterioration of surface roughness. Residual stress is generated on the surface by processing, but the FPG12 and 13 ( Figure 3 As shown in the figure, the plasma irradiation of the processed component 1 by FPG12 and 13 located on the right side can suppress the residual stress by performing gentle processing.

[0054] One surface of the resin 16a passing through the first holding portion 14 is treated. Thereafter, when the resin 16a passes through the first holding portion 15, a resin 16b with two treated surfaces is obtained. The resin 16b with two treated surfaces is wound around a portion of the guide roller 19. When the resin is a fluororesin such as PTFE, the two surfaces of the resin 16b are activated due to the detachment of fluorine and / or carbon. When the resin is a wholly aromatic polyester, the two surfaces of the resin 16b are activated due to the detachment of oxygen. The resin 16b is supplied to the second chamber 27 of the second processing device 92 that performs the introduction step S20 via the guide roller 19 in a state where the two surfaces are activated.

[0055] A connection portion 26 with differential exhaust is provided between the first chamber 25 and the second chamber 27. The differential exhaust separates the first chamber 25 from the second chamber 27, and the pressure in the first chamber 25 and the pressure in the second chamber 27 can be made different. As described above, by continuously performing the separation step S10 and the introduction step S20 using the first processing device 91 and the second processing device 92, respectively, high productivity can be ensured.

[0056] The second processing device 92 for performing the introduction step S20 includes a second chamber 27, second holding parts 22, 23, a second gas introduction part 18, a "second plasma generation part", and FPGs 20, 21 as "plasma irradiation sources". The second chamber 27 is grounded. The second holding parts 22, 23 hold the resin 16b to be processed in the first chamber 25, and a first DC voltage is applied by a power supply (not shown). The second holding parts 22, 23 include a heater 28 as a heating part. It is preferred that the temperature of the second holding parts 22, 23 is maintained at 150°C or more and 300°C or less by the heater 28. This is because hydroxyl groups can be effectively introduced onto the surface of the resin 16b.

[0057] The second gas introduction part 18 introduces the second gas that is plasmatized and generates hydroxyl radicals into the second chamber 27. In the first embodiment, the second gas is water vapor. The FPG 20, 21 plasmatizes the second gas, and a second DC voltage higher than the first DC voltage is applied by a power supply (not shown). For example, the first DC voltage is 40% or more and 99% or less of the second DC voltage. The resin 16b supplied from the first chamber 25 is held while being wound on a part of the columnar second holding part 22, 23.

[0058] The FPG 20 is arranged to be opposite to the second holding portion 22. The FPG 21 is arranged to be opposite to the second holding portion 23. By arranging the second holding portions 22, 23 and the FPG 20, 21 as described above, the introduction step S20 is performed on both surfaces of the resin in the second processing device 92. In addition, since two FPGs are arranged relative to one second holding portion, the introduction step S20 can be performed efficiently. In the introduction step S20, the pressure in the second chamber 27 is preferably 30% or more and 50% or less of the pressure in the first chamber 25, so that the hydroxyl group can be easily introduced to the surface of the resin 16b.

[0059] The potential difference between FPG 20, 21 and the second chamber 27 generates plasma of the second gas, and generates ions such as hydrogen ions and hydroxyl radicals. Only one surface of the resin 16c that has passed through the second holding portion 22 is hydrophilized. Both surfaces of the resin 16d that has passed through the second holding portion 23 are hydrophilized. The resin 16d is wound around the winding roller 24. After all surfaces of the resin are hydrophilized, the second chamber 27 is opened to the atmosphere, and the resin 16d is taken out.

[0060] Figure 4 The plasma processing device 95 of the second embodiment of the present application is schematically shown. The plasma processing device 95 includes a first processing device (not shown), a second processing device 93, and a third processing device 96 for performing the evaporation step S30. The second processing device 93 is substantially the same as the second processing device 92. The third processing device 96 includes a third chamber 65, third holding parts 68, 71, and metal evaporation parts 97, 98. The third holding parts 68, 71 hold the resin 16d to be processed in the second chamber 27.

[0061] The metal evaporation units 97 and 98 respectively evaporate metal on one surface of the resin 16d held by the third holding units 68 and 71. The metal evaporation unit 97 includes an FPG 67 as a "plasma irradiation source" and a copper target 66 as a metal target. That is, the ion beam released from the FPG 67 collides with the copper target 66, and the copper ejected from the copper target 66 is precipitated on one surface of the resin 16d to form a copper evaporation film. The thickness of the copper evaporation film is greater than 10nm and less than 400nm. In addition, the metal evaporation unit 98 has an FPG 70 as a "plasma irradiation source" and a copper target 69.

[0062] The resin 16d that has been subjected to the introduction step S20 in the second chamber 27 is supplied to the third chamber 65 via the guide roller 63. A connection portion 64 having differential exhaust is provided between the second chamber 27 and the third chamber 65. The resin 16d supplied from the third chamber 65 is held while being wound around a portion of the columnar third holding portion 68, 71. When the resin 16d passes through the third holding portion 68, a laminated body 62b having a copper vapor-deposited film formed on one surface of the resin 16d can be obtained.

[0063] Then, the laminate 62b passes through the third holding portion 71, and a laminate 62c having a copper vapor-deposited film formed on both surfaces of the resin 16d can be obtained. The laminate 62c is wound up by the winding roller 24. After the copper vapor-deposited film is formed on both surfaces of all the resins 16d, the third chamber 65 is opened to the atmosphere, and the laminate 62c is taken out. From the detachment step S10 to the vapor deposition step S30, it is preferable to continuously process under reduced pressure.

[0064] In the first embodiment, metals contained in the inner wall of the second chamber 27 and the parts disposed inside the second chamber 27 are suspended due to collision of ions in the plasma of the second gas. Some of these suspended metals may adhere to the resins 16b, 16c, and 16d. Therefore, it is preferred that at least a part of the inner wall of the second chamber 27, the plasma generating parts FPG20, 21, and the parts disposed inside the second chamber 27 that are in contact with the plasma are composed of the same metal (e.g., copper, gold, or silver) as the metal vapor-deposited in the third processing device. Since the metal vapor-deposited in the third processing device is the same as at least a part of the inner wall of the second chamber 27, FPG20, 21, and the parts disposed inside the second chamber 27, even if the metals suspended from the inner wall of the second chamber 27, FPG20, 21, and the parts disposed inside the second chamber adhere to the resins 16b, 16c, and 10d, it will not become a defective product.

[0065] In addition, if Figure 5 The plasma processing apparatus 100 of the third embodiment shown may include the following sheets 50 and 51 as the cover portion, which are made of the same metal as the metal vapor-deposited in the third processing apparatus and cover the inner wall of the second chamber 27 of the second processing apparatus 101 and the components provided inside the second chamber 27, such as at least a part of the FPG 20 and 21. Since the metal vapor-deposited in the third processing apparatus is the same as the metal constituting the sheets 50 and 51, even if the suspended metal from the sheets 50 and 51 adheres to the resins 16b, 16c and 16d, it will not become a defective product.

[0066] Figure 6 and Figure 7 The plasma processing device 110 of the fourth embodiment of the present application is schematically shown. In the fourth embodiment, the treated component is a sheet-like resin 30a. The plasma processing device 110 has vacuum standby chambers 38 and 41, a first processing chamber 111 for performing the separation step S10, a second processing chamber 112 for performing the introduction step S20, and gate valves 33, 34, 35, 36, and 37. The first processing chamber 111 has a first chamber 39. The second processing chamber 112 has second chambers 40a and 40b.

[0067] like Figure 7As shown, in the vacuum standby chamber 38, a movable portion 31 for holding the resin 30a at the end and a rail portion 32a for installing and transporting the movable portion 31 are provided. Similarly, in the first chamber 39, a rail portion 32b for transporting the movable portion 31 for holding the resin 30b is provided. In addition, in the second chamber 40a, a rail portion 32c for transporting the movable portion 31 for holding the resin 30c is provided. In addition, in the second chamber 40b, a rail portion 32d for transporting the movable portion 31 for holding the resin 30d is provided. In addition, in the vacuum standby chamber 41, a rail portion 32e for transporting the movable portion 31 for holding the resin 30e is provided. As a method for transporting the resins 30a, 30b, 30c, 30d, 30e, a linear guide or a rack and pinion may be used.

[0068] The plasma processing device 110 is operated as follows. The gate valve 33 is opened, and the movable part 31 holding the end of the resin 30a is installed on the track part 32a in the vacuum standby chamber 38. The gate valve 33 is closed, and the vacuum standby chamber 38 is depressurized. When the pressure in the vacuum standby chamber 38 becomes less than 10Pa, the gate valve 34 is opened. The movable part 31 moves to the first chamber 39, and the gate valve 34 is closed. Using FPG42, 43 as a "plasma irradiation source", the resin 30b is subjected to the separation step S10 in the first chamber 39 to obtain a resin 30c with two surfaces activated. At this time, by using two pairs of FPG42, 43, the resin 30b can be effectively and uniformly treated.

[0069] When the separation step S10 is completed, the resin 30c, i.e., the movable part 31, moves to the adjacent front of the gate valve 35. The gate valve 35 is opened, the movable part 31 moves to the second chamber 40a, and the gate valve 35 is closed. In the second chamber 40a, the introduction step S20 is performed on the upper surface of the resin 30c to obtain the resin 30d. The resin 30d, i.e., the movable part 31, moves to the adjacent front of the second chamber 40b. In the second chamber 40b, the introduction step S20 is performed on the lower surface of the resin 30d to obtain the resin 30e. At this time, the voltage applied to the electrode plate 45a is greater than the voltage of the grounded second chamber 40a and is less than the voltage applied to the FPG44a as the "plasma irradiation source". In addition, the voltage applied to the electrode plate 45b is greater than the voltage of the grounded second chamber 40b and is less than the voltage applied to the FPG44b as the "plasma irradiation source".

[0070] Therefore, most of the ions in the plasma of the processing gas move in the direction from FPG44a, 44b to the second chambers 40a, 40b, rather than in the direction from FPG44a, 44b to the electrode plates 45a, 45b. The remaining hydroxyl radicals in the plasma are irradiated onto the resins 30c, 30d. The resin 30e, i.e., the movable part 31, moves to the adjacent front of the gate valve 36. The gate valve 36 is opened, the movable part 31 is moved into the vacuum standby chamber 41, and the gate valve 36 is closed. After the vacuum standby chamber 41 is adjusted to atmospheric pressure, the gate valve 37 is opened, and the resin 30e is taken out.

[0071] Example

[0072] (Escape Steps)

[0073] In a grounded stainless steel chamber, a fine plasma gun (FPG) (manufactured by Fine solution Co., Ltd., linear type ion beam source FPG-L040S) (the same below) was used to perform a release step on a commercially available A4 size fluororesin substrate under the conditions of a chamber pressure of 0.3 Pa, a power supplied to the FPG of 300 W, and a processing gas of nitrogen or argon.

[0074] (Import steps)

[0075] In a grounded stainless steel chamber, a fine plasma gun (FPG) was used. The pressure in the chamber was 0.15a. The power supplied to the FPG was 300W. The processing gas was water vapor. The voltage applied to the holding table holding the substrate was set to be lower than the voltage applied to the FPG, and an introduction step was performed on the substrate that had undergone the release step.

[0076] Figure 8 (a) shows an image when the detachment step and the introduction step are not performed, that is, the contact angle between the substrate surface and water before the treatment is measured. Figure 8 As shown in (a), the water dropped on the surface of the substrate before treatment shrinks into a circle. That is, the surface of the substrate before treatment shows high water repellency. The contact angle between the surface of the substrate before treatment and water is greater than 90°. In addition, Figure 8 (b) shows an image when the detachment step and the introduction step are performed, that is, the contact angle between the treated substrate surface and water is measured. Figure 8 As shown in (b), water dropped on the surface of the treated substrate spreads. That is, the treated substrate surface shows high hydrophilicity.

[0077] Figure 8(c) shows a scanning electron microscope (SEM) image of the substrate surface before treatment. Scratches and holes generated when the fluororesin block was peeled off into sheets were observed. Figure 8 (d) shows an SEM image of the substrate surface after treatment. The scratches and holes observed on the substrate surface before treatment disappeared, and elongated concave and convex were observed. The concave and convex can be considered to be caused by irradiating the substrate with ions in the release step. As described above, the morphology of the substrate surface before and after treatment has changed significantly, but the surface roughness of the substrate has hardly changed.

[0078] Fig. 9 The results of measuring the contact angle of the treated fluororesin sheet surface with water are shown. The short side of the fluororesin sheet is set as the X-axis, the long side is set as the Y-axis, and the center of the fluororesin sheet is set as the coordinate (0, 0). The contact angle with water was measured at 15 points in total, including 5 points in the short side direction and 3 points in the long side direction. One point was measured twice and the average value was plotted. The deviation in the Y-axis direction was 0.3 to 1.9° at all points on the X-axis. In addition, the deviation in the X-axis direction was 1.6 to 1.9°. The contact angles of all measured points were less than 6°. In addition, when copper was directly plated on the surface of the treated substrate, the bonding degree between the substrate and the copper was 0.8 N / mm, and the substrate and the copper were firmly bonded.

[0079] Industrial Applicability

[0080] The resin surface hydrophilization method, plasma treatment device, laminate and laminate manufacturing method of the present application are used for circuit boards, which are used for mobile phones that transmit information at high speed and large capacity. Since the relative dielectric constant of fluororesin is second only to air, fluororesin substrates are particularly suitable as materials for high-frequency substrates. Compared with circuit boards made of other general materials, circuit boards using fluororesin have lower relative dielectric constants and dissipation factors even when high-frequency current flows, and have smaller dielectric losses.

[0081] When the resin surface hydrophilization method of the present application is applied to a fluororesin substrate, a circuit board can be provided that has improved hydrophilicity of the substrate and improved adhesion with copper wiring, and can withstand use in high frequency bands. The technology suitable for use in this high frequency band is not limited to mobile phone bodies, but can also be applied to mobile phone base station substrates, home, factory or regional dedicated communication substrates, or automobile, drone and other autonomous driving millimeter wave radar substrates, and has a wide range of applications.

[0082] Explanation of symbols

[0083] S10: Detaching step, S20: Introducing step, S30: Vapor deposition step, S40: Coating step, 1: Part to be processed, 2: Vacuum chamber, 3, 12, 13, 20, 21, 42, 43, 44a, 44b, 67, 70: Fine plasma gun (FPG, plasma irradiation source), 4: Holding table, 5: Cover, 6: Free radicals (hydroxyl groups), 7: Ions, 8: Second DC power supply, 9: First DC power supply, 10: Ground, 11: Supply roller, 14, 15: First holding part, 16a, 16b, 16c, 16d, 30a, 30b, 30c, 30d, 30e: Resin, 17: First gas introduction part, 18: Second gas introduction part, 19: Guide roller, 22, 23: Second holding part, 24: Winding roller, 25, 39: First chamber, 26, 64: Connecting part, 27, 40a, 40b: Second chamber, 28: Heater, 31: Movable part, 32a, 32b, 32c, 32d, 32e: Rail part, 33, 34, 35, 36, 37: Gate valve, 38, 41: Vacuum standby chamber, 45a, 45b: Electrode plate, 62b, 62c: Laminated body, 65: Third chamber, 68, 71: Third holding part, 66, 69: Copper target, 80: Processing device, 90, 95, 100, 110: Plasma processing device, 91, 111: First processing device, 92, 93, 101, 112: Second processing device, 96: Third processing device, 97, 98: Metal evaporation part.

Claims

1. A plasma processing device comprising a first processing device and a second processing device, The first processing device comprises: a first chamber; a first holding portion for holding a resin; a first gas introduction portion for introducing a first gas into the first chamber, wherein when the first gas is converted into plasma, at least a part of atoms constituting the resin is separated from the surface of the resin; and a first plasma generating portion for converting the first gas into plasma; The second processing device includes: a grounded second chamber; a second holding portion, which holds the resin processed by the first chamber, and a first DC voltage is applied to the second holding portion; a second gas introduction portion, which introduces a second gas into the second chamber, and the second gas is plasmatized to generate hydroxyl radicals; a second plasma generating portion, which plasmatizes the second gas, and a second DC voltage higher than the first DC voltage is applied to the second plasma generating portion. 2 . The plasma device according to claim 1 , wherein the second holding portion includes a heating portion.

3. The plasma device according to claim 1 or 2, further comprising a third processing device, The third processing device includes: a third holding portion that holds the resin processed in the second chamber; and a metal vapor deposition portion that vapor-deposits metal on the resin held by the third holding portion. 4 . The plasma apparatus according to claim 3 , wherein at least a part of an inner wall of the second chamber in contact with the plasma, the plasma generating portion, and a member provided inside the second chamber is made of the same metal as the metal.

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