Method for manufacturing a wiring circuit board, a wiring circuit board manufacturing system, and an electrolytic plating apparatus.

Abstract

The present invention provides a method for manufacturing a wiring circuit board, a manufacturing system for a wiring circuit board, and an electroplating apparatus that can reduce the depth (amount of recess) of recesses formed on the surface of the conductor layer while suppressing a decrease in productivity. [Solution] The manufacturing method for the wiring circuit board 1 includes a seed layer formation step and a conductor layer formation step. In the seed layer formation step, a seed layer 31 is formed on a substrate S having a recess R1, covering the inner surface of the recess R1. In the conductor layer formation step, a conductor layer 32 is formed on the seed layer 31. The conductor layer formation step includes a first plating step, a surface treatment step, and a second plating step. In the first plating step, a portion of the conductor layer 32 (conductor layer 32A) is formed by electroplating. In the surface treatment step, the surface of the conductor layer 32A is treated with a treatment solution containing acid. In the second plating step, a portion of the conductor layer 32 is further formed on the surface-treated conductor layer 32A by electroplating.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a wiring circuit board, a manufacturing system for a wiring circuit board, and an electrolytic plating apparatus.

Background Art

[0002] Conventionally, as a wiring circuit board, a wiring circuit board including an insulating layer having through holes and a conductor layer formed so as to fill the through holes is known (for example, see Patent Document 1 below).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the manufacture of a wiring circuit board as described in Patent Document 1 above, when the conductor layer is formed by electrolytic plating, the plating growth in the through holes may decrease, and recesses may be formed on the surface of the conductor layer.

[0005] The present invention provides a method for manufacturing a wiring circuit board, a manufacturing system for a wiring circuit board, and an electrolytic plating apparatus that can reduce the depth (amount of indentation) of recesses formed on the surface of the conductor layer while suppressing a decrease in productivity.

Means for Solving the Problems

[0006] The present invention [1] includes a method for manufacturing a wiring circuit board, comprising: a seed layer forming step of forming a seed layer covering the inner surface of a recess on a substrate having a recess; and a conductor layer forming step of forming a conductor layer on the seed layer, wherein the conductor layer forming step includes a first plating step of forming a part of the conductor layer by electroplating; a surface treatment step of treating the surface of the part of the conductor layer formed in the first plating step with a treatment solution containing acid; and a second plating step of further forming a part of the conductor layer on the surface-treated part of the conductor layer by electroplating.

[0007] According to this method, the conductive layer formation process includes multiple plating processes (a first plating process and a second plating process), and between each plating process, the surface of the conductive layer is treated with a treatment solution containing acid.

[0008] Therefore, it is possible to fill in depressions on the surface of the conductive layer without increasing the time of each plating process.

[0009] As a result, the depth (amount of recess) of the recesses formed on the surface of the conductor layer can be reduced while suppressing a decrease in productivity.

[0010] The present invention [2] includes a method for manufacturing the wiring circuit board described in [1], wherein the substrate comprises a metal layer and an insulating layer disposed on the metal layer and having through holes, the recess includes the through holes, and the seed layer covers the surface of the insulating layer, the inner surface of the through holes, and the surface of the metal layer within the through holes.

[0011] The present invention [3] includes a method for manufacturing a wiring circuit board according to [1] or [2] above, wherein in the surface treatment step, the substrate having the part of the conductor layer is immersed in the treatment liquid.

[0012] This method ensures that the surface of the conductive layer is reliably treated with the treatment solution.

[0013] The present invention [4] includes a method for manufacturing a wiring circuit board according to any one of the above [1] to [3], further comprising a water washing step of washing the substrate with water after the surface treatment step and before the second plating step.

[0014] This method removes the treatment solution adhering to the substrate, thereby preventing the treatment solution from contaminating the plating tank in the second plating process.

[0015] The present invention [5] includes a method for manufacturing a wiring circuit board according to any one of the above [1] to [4], wherein the pH of the processing solution is 5 or less.

[0016] The present invention [6] includes a method for manufacturing a wiring circuit board according to any one of the above [1] to [5], wherein the acid in the processing solution is the same as the acid in the plating solution used in the second plating step.

[0017] The present invention [7] includes a seed layer forming apparatus capable of forming a seed layer on a substrate, and an electroplating apparatus capable of forming a conductor layer on the seed layer by electroplating, wherein the electroplating apparatus comprises a first plating tank on which a part of the conductor layer is formed, a surface treatment apparatus disposed downstream of the first plating tank in the flow direction of the substrate and capable of treating the surface of the part of the conductor layer formed in the first plating tank with an acid-containing treatment solution, and a second plating tank disposed downstream of the surface treatment apparatus in the flow direction, and is a manufacturing system for a wiring circuit board.

[0018] In this configuration, the electroplating apparatus comprises multiple plating tanks (a first plating tank and a second plating tank), and a surface treatment device is positioned between each plating tank. The surface treatment device treats the surface of the conductive layer with a treatment solution containing acid.

[0019] Therefore, it is possible to fill in depressions on the surface of the conductive layer without increasing the time of each plating process.

[0020] As a result, the depth (amount of recess) of the recesses formed on the surface of the conductor layer can be reduced while suppressing a decrease in productivity.

[0021] The manufacturing system of the wiring circuit board of [7] above includes the present invention [8], in which the seed layer forming device is a sputtering device.

[0022] The manufacturing system of the wiring circuit board of [7] or [8] above includes the present invention [9], in which the electrolytic plating device is arranged between the surface treatment device and the second plating bath in the flow direction, and further includes a cleaning device capable of cleaning the base material with water.

[0023] According to such a configuration, it is possible to remove the treatment liquid adhering to the base material and suppress the mixing of the treatment liquid into the second plating bath.

[0024] The manufacturing system of the wiring circuit board of any one of [7] to [9] above includes the present invention

[10] , in which the electrolytic plating device is arranged between the first plating bath and the surface treatment device in the flow direction, and further includes a power supply device capable of contacting a part of the seed layer.

[0025] The manufacturing system of the wiring circuit board of any one of [7] to [9] above includes the present invention

[11] , in which the electrolytic plating device is arranged between the surface treatment device and the second plating bath in the flow direction, and further includes a power supply device capable of contacting a part of the seed layer.

[0026] The present invention

[12] is an electrolytic plating device used for manufacturing a wiring circuit board, which includes a first plating bath capable of forming a part of a conductor layer on the seed layer of a base material on which a seed layer is formed, a surface treatment device arranged on the downstream side of the first plating bath in the flow direction of the base material, and capable of treating the surface of the part of the conductor layer formed in the first plating bath with a treatment liquid containing an acid, and a second plating bath arranged on the downstream side of the surface treatment device in the flow direction.

[0027] In this configuration, the electroplating apparatus comprises multiple plating tanks (a first plating tank and a second plating tank), and a surface treatment device is positioned between each plating tank. The surface treatment device treats the surface of the conductive layer with a treatment solution containing acid.

[0028] Therefore, it is possible to fill in depressions on the surface of the conductive layer without increasing the time of each plating process.

[0029] As a result, the depth (amount of recess) of the recesses formed on the surface of the conductor layer can be reduced while suppressing a decrease in productivity. [Effects of the Invention]

[0030] According to the method for manufacturing a wiring circuit board, the manufacturing system for a wiring circuit board, and the electroplating apparatus of the present invention, it is possible to reduce the depth (amount of recess) of recesses formed on the surface of the conductor layer while suppressing a decrease in productivity. [Brief explanation of the drawing]

[0031] [Figure 1] Figure 1 is a cross-sectional view of a wiring circuit board manufactured by the wiring circuit board manufacturing method of the present invention. [Figure 2] Figures 2A to 2D are process diagrams showing one embodiment of the manufacturing method for a wiring circuit board according to the present invention, where Figure 2A shows the insulating layer formation process, Figure 2B shows the seed layer formation process, Figure 2C shows the first plating process, and Figure 2D shows the second plating process. [Figure 3] Figure 3 is a configuration diagram showing one embodiment of the electroplating apparatus of the present invention. [Figure 4] Figure 4 is a configuration diagram showing a modified example (1) of an electroplating apparatus. [Figure 5] Figure 5 is a configuration diagram showing a modified example (2) of the electroplating apparatus. [Figure 6] Figure 6 is a configuration diagram showing a modified example (3) of the electroplating apparatus. [Modes for carrying out the invention]

[0032] 1. Wiring circuit board First, a wiring circuit board 1 manufactured by the wiring circuit board manufacturing method of the present invention will be described. The wiring circuit board 1 is, for example, a rewiring board for semiconductor packages. The wiring circuit board 1 may be a flexible wiring circuit board or a suspension board with circuits.

[0033] As shown in Figure 1, the wiring circuit board 1 comprises, for example, an insulating layer 2, a circuit pattern 3, and a metal layer 4.

[0034] (1) Insulating layer 2 The insulating layer 2 is positioned between the circuit pattern 3 and the metal layer 4 in the thickness direction of the insulating layer 2. The insulating layer 2 insulates the circuit pattern 3 from the metal layer 4. The insulating layer 2 is made of resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. The insulating layer 2 has through holes 21. The through holes 21 are, for example, via holes.

[0035] The thickness of the insulating layer 2 is, for example, 15 μm to 50 μm or more, preferably 25 μm to 40 μm.

[0036] (2) Circuit Pattern The circuit pattern 3 is positioned on one side of the insulating layer 2 in the thickness direction. The circuit pattern 3 is positioned on one side surface of the insulating layer 2 in the thickness direction. The circuit pattern 3 is positioned on the opposite side of the metal layer 4 from the insulating layer 2 in the thickness direction. The shape of the circuit pattern 3 is not limited. The circuit pattern 3 is connected to the metal layer 4 through a through hole 21. The circuit pattern 3 has a seed layer 31 and a conductor layer 32.

[0037] The seed layer 31 is placed between the insulating layer 2 and the conductive layer 32. The seed layer 31 is made of metal. Examples of materials for the seed layer 31 include chromium, copper, nickel, titanium, and alloys thereof.

[0038] The conductive layer 32 is placed on the seed layer 31. The conductive layer 32 is made of metal. Examples of materials for the conductive layer 32 include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. The conductive layer 32 is preferably made of copper.

[0039] The thickness T1 of the conductive layer 32 on one side surface of the insulating layer 2 is, for example, 3 μm to 20 μm, preferably 5 μm to 10 μm.

[0040] The thickness T2 of the conductive layer 32 inside the through hole 21 is greater than the thickness T1. The thickness T2 is, for example, 3 μm to 50 μm, preferably 5 μm to 30 μm.

[0041] The ratio of thickness T2 to thickness T1 (T2 / T1) is, for example, 1 to 10, preferably 2 to 8.

[0042] The conductive layer 32 may have a recess R.

[0043] The recess R is located on one side surface of the conductor layer 32 in the thickness direction. The recess R overlaps with the through hole 21 of the insulating layer 2 in the thickness direction.

[0044] The depth of the recess R in the thickness direction (amount of recess D) is less than the thickness T1. Preferably, the conductive layer 32 does not have a recess R. In other words, the amount of recess D may be 0.

[0045] (3) Metal layer The metal layer 4 is positioned on the other side of the insulating layer 2 in the thickness direction. The metal layer 4 is positioned on the other side surface of the insulating layer 2 in the thickness direction. Examples of materials for the metal layer 4 include stainless steel, Invar, 42 alloy, copper alloy, copper, and aluminum.

[0046] 2. Manufacturing method of a wiring circuit board Next, an embodiment of the method for manufacturing the wiring circuit board of the present invention will be described.

[0047] As shown in Figures 2A to 2D, the method for manufacturing a wiring circuit board includes an insulating layer formation step (see Figure 2A), a seed layer formation step (see Figure 2B), and a conductor layer formation step (see Figures 2C and 2D).

[0048] (1) Insulating layer formation process As shown in Figure 2A, in the insulating layer formation process, an insulating layer 2 is formed on one side surface of the metal layer 4 in the thickness direction.

[0049] In the insulating layer formation process, for example, a photosensitive resin solution (varnish) is applied to one side surface of the metal layer 4 in the thickness direction and dried to form a photosensitive resin coating. Next, the photosensitive resin coating is exposed to light and developed.

[0050] In addition, during the insulating layer formation process, a film made of insulating resin may be attached to one side surface of the metal layer 4 in the thickness direction, and through holes 21 may be formed in the film using a laser or drill.

[0051] This results in a substrate S having a metal layer 4 and an insulating layer 2 disposed on the metal layer 4. The substrate S has a recess R1. The recess R1 includes a through hole 21.

[0052] (2) Seed layer formation process Next, as shown in Figure 2B, in the seed layer formation step, a seed layer 31 is formed on the substrate S.

[0053] The seed layer 31 covers one side surface of the substrate S in the thickness direction and the inner surface of the recess R1. More specifically, the seed layer 31 covers one side surface of the insulating layer 2 in the thickness direction, the inner surface of the through hole 21, and the surface of the metal layer 4 inside the through hole 21.

[0054] The seed layer 31 is formed, for example, by sputtering. The seed layer 31 may also be formed by electroless plating or vapor deposition.

[0055] (3) Conductor layer formation process Next, as shown in Figures 2C and 2D, in the conductor layer formation process, a conductor layer 32 is formed on the seed layer 31.

[0056] The conductor layer formation process includes multiple plating steps. Specifically, the conductor layer formation process includes a first plating step (see Figure 2C), a surface treatment step, and a second plating step (see Figure 2D).

[0057] Furthermore, the number of plating steps in the conductor layer formation process is not limited to two. The number of plating steps in the conductor layer formation process may be three or more. That is, the conductor layer formation process may include a third plating step after the second plating step, and a surface treatment step may also be included between the second and third plating steps.

[0058] (3-1) First plating process As shown in Figure 2C, in the first plating process, a portion of the conductive layer 32 is formed by electroplating.

[0059] For more details, first, the seed layer 31 is coated with plating resist PR.

[0060] Next, the plating resist PR is exposed and developed. This removes the plating resist PR in the areas where the conductive layer 32 will be formed, exposing the seed layer 31 in those areas. On the other hand, the plating resist PR remains in the areas where the conductive layer 32 will not be formed.

[0061] Next, a conductive layer 32 is formed on the exposed seed layer 31 by electroplating.

[0062] When the conductive layer 32 is made of copper, the plating solution used in the first plating step (first plating solution) is, for example, a copper sulfate plating solution.

[0063] The copper sulfate plating solution contains copper sulfate pentahydrate, sulfuric acid, and chloride ions.

[0064] The proportion of copper sulfate pentahydrate in the copper sulfate plating solution is, for example, 100 g / L to 320 g / L, preferably 180 g / L to 280 g / L.

[0065] The proportion of sulfuric acid in the copper sulfate plating solution is, for example, 15 g / L to 150 g / L, preferably 25 g / L to 100 g / L.

[0066] The proportion of chloride ions in the copper sulfate plating solution is, for example, 10 ppm to 100 ppm by mass, preferably 15 ppm to 60 ppm.

[0067] A portion of the conductive layer 32 formed in the first plating process (hereinafter referred to as conductive layer 32A) has a recess R2 corresponding to the recess R1 of the substrate S.

[0068] (3-2) Surface treatment process The surface treatment process is performed between each plating process, that is, in this embodiment, between the first plating process and the second plating process. In the surface treatment process, the surface of the conductive layer 32A is treated with a treatment solution. More specifically, the surface treatment process removes the oxide film formed on the surface of the conductive layer 32A. Note that "the surface of the conductive layer 32A" refers to one side surface of the conductive layer 32A in the thickness direction, and the inner surface of the recess R2.

[0069] The treatment solution is capable of dissolving the oxide film formed on the surface of the conductive layer 32A, but does not dissolve the conductive layer 32A itself. The treatment solution contains an acid. Examples of treatment solutions include acidic aqueous solutions, excluding etching solutions.

[0070] Examples of acidic aqueous solutions include aqueous solutions of inorganic acids and aqueous solutions of organic acids. Examples of inorganic acids include sulfuric acid, hydrochloric acid, and phosphoric acid. Examples of organic acids include citric acid, acetic acid, formic acid, oxalic acid, malonic acid, and glycolic acid.

[0071] Examples of etching solutions include ferric chloride aqueous solution, sulfuric acid / hydrogen peroxide mixture, nitric acid / hydrogen peroxide mixture, sodium persulfate aqueous solution, ammonium persulfate aqueous solution, and potassium persulfate aqueous solution.

[0072] The acid in the treatment solution is preferably the same as the acid in the plating solution used in the second plating step (second plating solution). The second plating solution will be explained later. For example, if the second plating solution is a copper sulfate plating solution, the treatment solution is preferably dilute sulfuric acid. The acid in the treatment solution may be different from the acid in the second plating solution.

[0073] The pH of the processing solution is lower than the pH of the first plating solution. The pH of the processing solution is, for example, less than 7, preferably 5 or less, more preferably 1 or less, more preferably 0.4 or less, more preferably 0.18 or less, and more preferably 0.16 or less. The pH of the processing solution is, for example, 0 or higher.

[0074] The method of the surface treatment process is not limited. For example, the substrate S having the conductive layer 32A may be immersed in a treatment solution, or the treatment solution may be sprayed onto the substrate S having the conductive layer 32A. Preferably, in the surface treatment process, the substrate S is immersed in a treatment solution. The surface treatment process removes the oxide film formed on the surface of the conductive layer 32A.

[0075] (3-4) Second plating process As shown in Figure 2D, in the second plating step, a portion of the conductor layer 32 is further formed on the surface-treated conductor layer 32A (see Figure 2C) by electroplating. In other words, in the second plating step, a portion of the conductor layer 32 is further formed on the surface of the conductor layer 32A (see Figure 2C) from which the oxide film has been removed by the surface treatment step. This suppresses the inhibition of plating growth within the recesses R2 of the conductor layer 32A by the oxide film, and allows the recesses R2 to be filled. This reduces the depth (amount of recess D) of the recesses R formed on the surface of the conductor layer 32.

[0076] The type of plating solution used in the second plating process (second plating solution) is the same as the type of plating solution used in the first plating process. For example, if the first plating solution is a copper sulfate plating solution, then the second plating solution will also be a copper sulfate plating solution.

[0077] The composition ratio of the second plating solution may differ from that of the first plating solution. Furthermore, the plating conditions for the second plating process (e.g., temperature of the plating solution, current density, or processing time) may be the same as or different from those for the first plating process.

[0078] 3. Manufacturing system for wiring circuit boards Next, an embodiment of the wiring circuit board manufacturing system of the present invention will be described. The wiring circuit board manufacturing system can be used in the wiring circuit board manufacturing method described above.

[0079] The wiring circuit board manufacturing system comprises a seed layer forming apparatus and an electroplating apparatus 10 (see Figure 3). In other words, the electroplating apparatus 10 is used for manufacturing wiring circuit boards.

[0080] (1) Seed layer forming apparatus The seed layer forming apparatus is used in the seed layer forming process described above. The seed layer forming apparatus is capable of forming a seed layer 31 on a substrate S. When the seed layer 31 is formed by sputtering, the seed layer forming apparatus is a sputtering apparatus. When the seed layer 31 is formed by electroless plating, the seed layer forming apparatus is a plating apparatus. When the seed layer 31 is formed by vapor deposition, the seed layer forming apparatus is a vapor deposition apparatus.

[0081] (2) Electrolytic plating apparatus The electroplating apparatus 10 is used in the conductor layer formation process described above. The electroplating apparatus 10 is capable of forming a conductor layer 32 on the seed layer 31 by electroplating.

[0082] More specifically, as shown in Figure 3, the electrolytic plating apparatus 10 is a roll-to-roll type continuous plating apparatus. The transport direction of the substrate S may be horizontal or vertical. The plating electrode may be a soluble electrode or an insoluble electrode.

[0083] The electroplating apparatus 10 comprises a first plating tank 11, a power supply roller 12 as an example of a power supply device, a surface treatment device 13, and a second plating tank 14.

[0084] (2-1) First plating tank The first plating tank 11 is used in the first plating process described above. In other words, a conductive layer 32A (part of the conductive layer 32) is formed in the first plating tank 11. To put it another way, the first plating tank 11 is capable of forming a conductive layer 32A (part of the conductive layer 32) on the seed layer 31 of the substrate S on which the seed layer 31 is formed. The first plating solution described above is stored in the first plating tank 11.

[0085] (2-2) Power supply roller The power supply roller 12 is positioned between the first plating tank 11 and the second plating tank 14 in the flow direction of the substrate S. The power supply roller 12 is positioned between the first plating tank 11 and the surface treatment apparatus 13 in the flow direction. The power supply roller 12 can contact a portion of the seed layer 31. For example, the power supply roller 12 contacts the seed layer 31 exposed from the plating resist PR at both ends in the width direction of the substrate S. This allows power to be supplied to the seed layer 31 of the substrate S moving in the first plating tank 11 and to the seed layer 31 of the substrate S moving in the second plating tank 14.

[0086] (2-3) Surface treatment apparatus The surface treatment apparatus 13 is used in the surface treatment process described above. The surface treatment apparatus 13 can treat the surface of the conductive layer 32A (part of the conductive layer 32, see Figure 2C) formed in the first plating tank 11 with a treatment solution.

[0087] The surface treatment apparatus 13 is positioned downstream of the first plating tank 11 in the flow direction. The surface treatment apparatus 13 is positioned between the first plating tank 11 and the second plating tank 14 in the flow direction. In this embodiment, the surface treatment apparatus 13 is positioned between the power supply roller 12 and the second plating tank 14 in the flow direction.

[0088] In this embodiment, the surface treatment apparatus 13 has a treatment tank in which a treatment liquid is stored. The substrate S having the conductive layer 32A is immersed in the treatment liquid in the treatment tank.

[0089] (2-5) Second plating tank The second plating tank 14 is used in the second plating process described above. In other words, in the second plating tank 14, a portion of the conductive layer 32 is further formed on top of the surface-treated conductive layer 32A (see Figure 2C).

[0090] The second plating tank 14 is located downstream of the surface treatment apparatus 13 in the flow direction. The second plating solution described above is stored in the second plating tank 14.

[0091] 4. Effects (1) According to the method for manufacturing a wiring circuit board, as shown in Figures 2C and 2D, the conductor layer formation step includes multiple plating steps (first plating step and second plating step), and between each plating step, the surface of the conductor layer 32A (see Figure 2C) is treated with a treatment solution containing acid.

[0092] Therefore, the recesses R2 on the surface of the conductor layer 32A (see Figure 2C) can be filled without increasing the time of each plating process.

[0093] As a result, the depth of the recess R (amount of recess D, see Figure 1) formed on the surface of the conductor layer 32 can be reduced while suppressing a decrease in productivity.

[0094] (2) In the method for manufacturing a wiring circuit board, in the surface treatment step, a substrate S having a conductive layer 32A is immersed in a treatment solution.

[0095] Therefore, the surface of the conductive layer 32A can be reliably treated with the treatment solution.

[0096] (3) According to the wiring circuit board manufacturing system, as shown in Figure 3, the electrolytic plating apparatus 10 is equipped with a plurality of plating tanks (first plating tank 11 and second plating tank 14), and a surface treatment apparatus 13 is placed between the first plating tank 11 and the second plating tank 14.

[0097] Therefore, the recesses R2 on the surface of the conductor layer 32A (see Figure 2C) can be filled without increasing the time of each plating process.

[0098] As a result, the depth of the recess R (amount of recess D, see Figure 1) formed on the surface of the conductor layer 32 can be reduced while suppressing a decrease in productivity.

[0099] (4) As shown in Figure 3, the electrolytic plating apparatus 10 is equipped with a plurality of plating tanks (first plating tank 11 and second plating tank 14), and the surface treatment apparatus 13 is positioned between the first plating tank 11 and the second plating tank 14.

[0100] Therefore, the recesses R2 on the surface of the conductor layer 32A (see Figure 2C) can be filled without increasing the time of each plating process.

[0101] As a result, the depth of the recess R (amount of recess D, see Figure 1) formed on the surface of the conductor layer 32 can be reduced while suppressing a decrease in productivity.

[0102] 5. Variations Next, a modified example will be described. In the modified example, the same reference numerals are used for components similar to those in the above-described embodiment, and their descriptions are omitted.

[0103] (1) As shown in Figure 4, the electroplating apparatus 10 may be equipped with a cleaning device 15. The cleaning device 15 is positioned in the flow direction in front of the surface treatment apparatus 13 and the second plating tank 14. The cleaning device 15 can clean the substrate S with water. In other words, the conductive layer formation process described above may include a water washing process. The water washing process is performed after the surface treatment process and before the second plating process. In the water washing process, the substrate S is washed with water. This removes the treatment solution adhering to the substrate S and prevents the treatment solution from mixing into the second plating tank 14. If the acid in the treatment solution used in the surface treatment apparatus 13 is different from the acid in the second plating solution, the electroplating apparatus 10 preferably includes a cleaning device 15. The cleaning device 15 sprays water onto the substrate S, for example.

[0104] This modified example also provides the same effects and benefits as the embodiment described above.

[0105] (2) As shown in Figure 5, the power supply roller 12 may be positioned between the surface treatment apparatus 13 and the second plating tank 14 in the flow direction.

[0106] This modified example also provides the same effects and benefits as the embodiment described above.

[0107] (3) As shown in Figure 6, when the power supply roller 12 is positioned between the surface treatment apparatus 13 and the second plating tank 14 in the flow direction, the cleaning apparatus 15 is positioned in front of the surface treatment apparatus 13 and the power supply roller 12 in the flow direction.

[0108] This modified example also provides the same effects and benefits as the embodiment described above.

[0109] (4) The wiring circuit board 1 may include a circuit pattern 3 formed on one side surface of the substrate S in the thickness direction and a circuit pattern 3 formed on the other side surface of the substrate S in the thickness direction.

[0110] In that case, the electroplating apparatus 10 may include a power supply roller 12 that can contact one side surface of the substrate S in the thickness direction, and a power supply roller 12 that can contact the other side surface of the substrate S in the thickness direction.

[0111] This modified example also provides the same effects and benefits as the embodiment described above.

[0112] (5) The power supply device is not limited to the power supply roller 12. The power supply device may be of the clamp type.

[0113] This modified example also provides the same effects and benefits as the embodiment described above. [Examples]

[0114] The present invention will be further described below with reference to examples and comparative examples. However, the present invention is not limited in any way to the examples and comparative examples. Furthermore, specific numerical values ​​such as blending ratios (content ratios), physical properties, and parameters used in the following description may be replaced with the upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than or equal to") of the corresponding blending ratios (content ratios), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above.

[0115] 1. Manufacturing of wiring circuit boards (1) Example 1 A photosensitive polyimide solution (varnish) was applied to a stainless steel metal layer and dried to form a photosensitive resin coating. Next, the photosensitive polyimide coating was exposed to light and developed to form an insulating layer (30 μm thick) with via holes (insulating layer formation step).

[0116] Next, a seed layer was formed by sputtering. The seed layer covers one side surface of the insulating layer in the thickness direction, the inner surface of the via hole, and the surface of the metal layer inside the via hole (seed layer formation process).

[0117] Next, a plating resist was formed on the seed layer, and a conductive layer was formed by electrolytic copper plating using a roll-to-roll continuous plating apparatus (number of plating baths: 5) (conductive layer formation process).

[0118] In the conductive layer formation process, copper sulfate plating solution (copper sulfate pentahydrate: 220 g / L, sulfuric acid: 60 g / L, chloride ions: 40 ppm) is used in each plating bath, with a plating solution temperature of 25°C and a current density of 0.8 A / dm². 2 Under these conditions, electrolytic copper plating was performed for 8 minutes.

[0119] Furthermore, the substrate was immersed in a treatment solution (10.0% dilute sulfuric acid, pH: 0) between each plating tank (surface treatment process). The pH of the treatment solution was measured at 23°C using a handheld pH meter (manufactured by Horiba, Ltd.).

[0120] (2) Example 2 A wiring circuit board was manufactured in the same manner as in Example 1, except that 7.0% dilute sulfuric acid (pH: 0.17) was used as the treatment solution in the surface treatment process.

[0121] (3) Example 3 A wiring circuit board was manufactured in the same manner as in Example 1, except that 5.0% dilute sulfuric acid (pH: 0.18) was used as the treatment solution in the surface treatment process.

[0122] (4) Example 4 A wiring circuit board was manufactured in the same manner as in Example 1, except that a 3.5% dilute sulfuric acid (pH: 0.19) was used as the treatment solution in the surface treatment process.

[0123] (5) Example 5 A wiring circuit board was manufactured in the same manner as in Example 1, except that a mixed aqueous solution of copper sulfate pentahydrate and sulfuric acid (pH: 0.18) was used as the treatment solution in the surface treatment process.

[0124] (6) Example 6 A wiring circuit board was manufactured in the same manner as in Example 1, except that a citric acid aqueous solution (pH: 0.5) was used as the treatment solution in the surface treatment process.

[0125] (7) Comparative Example 1 A wiring circuit board was obtained in the same manner as in Example 1, except that electrolytic copper plating was performed in a single plating bath for 40 minutes without performing a surface treatment step.

[0126] In Comparative Example 1, the line speed was slower compared to Example 1, resulting in lower productivity.

[0127] (8) Comparative Example 2 A wiring circuit board was obtained in the same manner as in Example 1, except that the surface treatment process was omitted.

[0128] (9) Comparative Example 3 A wiring circuit board was manufactured in the same manner as in Example 1, except that an etching solution (sulfuric acid / hydrogen peroxide mixture) was used as the treatment solution in the surface treatment process.

[0129] 2. Measurement of the amount of indentation The amount of recess in the conductor layer surface of the wiring circuit boards obtained in each example and comparative example was measured using a laser microscope. The results are shown in Table 1.

[0130] [Table 1] [Explanation of Symbols]

[0131] 1 Wiring circuit board 2. Insulating layer 21 Through holes 31 Seed Layer 32 Conductor layer 32A Conductor layer (part of conductor layer 32) 4 metal layer 10 Electrolytic plating apparatus 11. First Plating Tank 12 Power supply roller (an example of a power supply device) 13 Surface treatment equipment 14. Second plating tank 15. Washing device S base material R1 recess

Claims

1. A seed layer forming step, in which a seed layer is formed on a substrate having a recess to cover the inner surface of the recess, A conductor layer formation step in which a conductor layer is formed on the seed layer, Includes, The aforementioned conductor layer formation step is, A first plating step in which a portion of the conductor layer is formed by electroplating, A surface treatment step in which the surface of a portion of the conductive layer formed in the first plating step is treated with a treatment solution containing acid, A second plating step is performed in which a portion of the conductive layer is further formed on the surface-treated portion of the conductive layer by electroplating. A method for manufacturing a wiring circuit board, including the method described above.

2. The aforementioned substrate is Metal layer, An insulating layer having through holes is disposed on the metal layer and It has, The recess includes the through hole, The method for manufacturing a wiring circuit board according to claim 1, wherein the seed layer covers the inner surface of the through hole and the surface of the metal layer within the through hole.

3. A method for manufacturing a wiring circuit board according to claim 1, wherein in the surface treatment step, the substrate having the part of the conductive layer is immersed in the treatment liquid.

4. A method for manufacturing a wiring circuit board according to claim 1, further comprising a water washing step of washing the substrate with water after the surface treatment step and before the second plating step.

5. The method for manufacturing a wiring circuit board according to claim 1, wherein the pH of the processing solution is 5 or less.

6. The method for manufacturing a wiring circuit board according to claim 1, wherein the acid in the processing solution is the same as the acid in the plating solution used in the second plating step.

7. A seed layer forming apparatus capable of forming a seed layer on a substrate, An electroplating apparatus capable of forming a conductive layer on the seed layer by electroplating, Equipped with, The electrolytic plating apparatus, A first plating tank in which a portion of the conductive layer is formed, A surface treatment apparatus is provided, which is positioned downstream of the first plating tank in the flow direction of the substrate, and capable of treating a portion of the surface of the conductive layer formed in the first plating tank with a treatment solution containing acid. A second plating tank is located downstream of the surface treatment apparatus in the flow direction. A manufacturing system for wiring circuit boards, equipped with the following features.

8. The manufacturing system for a wiring circuit board according to claim 7, wherein the seed layer forming apparatus is a sputtering apparatus.

9. The electrolytic plating apparatus, The wiring circuit board manufacturing system according to claim 7, further comprising a cleaning device disposed between the surface treatment apparatus and the second plating tank in the flow direction, and capable of washing the substrate with water.

10. The electrolytic plating apparatus, The wiring circuit board manufacturing system according to claim 7, further comprising a power supply device disposed between the first plating tank and the surface treatment apparatus in the flow direction and capable of contacting a portion of the seed layer.

11. The electrolytic plating apparatus, The wiring circuit board manufacturing system according to claim 7, further comprising a power supply device disposed between the surface treatment apparatus and the second plating tank in the flow direction and capable of contacting a portion of the seed layer.

12. An electroplating apparatus used in the manufacture of wiring circuit boards, A first plating tank capable of forming a portion of a conductive layer on the seed layer of a substrate on which a seed layer has been formed, A surface treatment apparatus is provided, which is positioned downstream of the first plating tank in the flow direction of the substrate, and capable of treating a portion of the surface of the conductive layer formed in the first plating tank with a treatment solution containing acid. A second plating tank is located downstream of the surface treatment apparatus in the flow direction. An electrolytic plating apparatus equipped with the following features.

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