aggregate sheet, and method for manufacturing an aggregate sheet

Abstract

To provide an aggregate sheet that enables inspection of the quality of a wiring circuit board without breaking a second terminal, and to provide a method of manufacturing the same.SOLUTION: An aggregate sheet 1 comprises a wiring circuit board 2, and an inspection part 4 arranged so as to be separated from the wiring circuit board 2. The wiring circuit board 2 has: a base insulating layer 22; a first terminal 231A arranged at one side of the base insulating layer 22 in a thickness direction; a metal support layer 21 formed of a first metal and arranged at the other side of the base insulating layer 22 in the thickness direction; and a second terminal 241 arranged at the other side of the base insulating layer 22 in the thickness direction. The second terminal 241 has a terminal main body 2411 formed of the first metal, and a coating layer 2412 formed of a second metal. The inspection part 4 has a first layer 41 formed of the first metal, and a second layer 42 formed of the second metal.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an aggregate sheet and a method for manufacturing the aggregate sheet.

Background Art

[0002] Conventionally, as an example of a wiring circuit board, a flexure for a disk device including a metal base, an insulating layer formed on the metal base, and a conductor group formed in a predetermined pattern on the insulating layer is known (see, for example, Patent Document 1 below).

[0003] In this flexure for a disk device, a circuit portion is formed in a part of the metal base. The circuit portion is connected to a part of the conductor group through a hole in the insulating layer. A gold plating layer is formed on the circuit portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a wiring circuit board as described in Patent Document 1, there may be a case where, as a quality inspection, for example, the adhesion of the gold plating layer in the circuit portion is to be inspected.

[0006] However, when performing a quality inspection using the circuit portion, there is a possibility that the circuit portion may be damaged.

[0007] The present invention provides an aggregate sheet that allows quality inspection of a wiring circuit board without damaging the second terminal, in a wiring circuit board having an insulating layer, a first terminal disposed on one side of the insulating layer in the thickness direction, a metal support layer disposed on the other side of the insulating layer in the thickness direction, and a second terminal disposed on the other side of the insulating layer in the thickness direction, and a method for manufacturing the aggregate sheet. [Means for solving the problem]

[0008] The present invention [1] includes a wiring circuit board and an inspection unit disposed away from the wiring circuit board, wherein the wiring circuit board has an insulating layer, a first terminal disposed on one side of the insulating layer in the thickness direction, a metal support layer made of a first metal disposed on the other side of the insulating layer in the thickness direction, and a second terminal disposed away from the metal support layer on the other side of the insulating layer in the thickness direction, the second terminal having a terminal body made of the first metal and a covering layer made of a second metal different from the first metal that covers the terminal body, and the inspection unit having a first layer made of the first metal and a second layer made of the second metal that covers the first layer, the assembled sheet.

[0009] In this configuration, the second terminal of the wiring circuit board has a layer structure consisting of a layer made of a first metal (terminal body) and a layer made of a second metal (coating layer). The inspection unit, which is located separately from the wiring circuit board, also has a layer structure consisting of a layer made of a first metal (first layer) and a layer made of a second metal (second layer). In other words, the inspection unit has the same layer structure made of the same material as the second terminal.

[0010] Therefore, the quality of the second terminal can be estimated based on the results of the quality inspection conducted on the inspection department.

[0011] As a result, the inspection unit can be used to perform quality inspections on the wiring circuit board without damaging the second terminal.

[0012] The present invention [2] includes the aggregate sheet of [1] above, wherein the second metal is gold or nickel.

[0013] The present invention [3] includes an aggregate sheet of [1] or [2] described above, wherein the second terminal is made of a third metal different from both the first metal and the second metal, and further comprises a second coating layer covering the coating layer, and the inspection portion is made of the third metal and further comprises a third layer covering the second layer.

[0014] The present invention [4] includes the aggregate sheet of [3] above, wherein the second metal is nickel and the third metal is gold.

[0015] The present invention [5] includes any one of the aggregate sheets described in [1] to [4] above, wherein the width of at least a portion of the inspection area is 30 μm or more.

[0016] This configuration allows for sufficient space in the inspection unit, and enables easy quality inspection using the inspection unit.

[0017] The present invention [6] includes any one of the above [1] to [5] assembly sheets, wherein the assembly sheet further comprises a frame supporting the wiring circuit board, and the inspection unit is disposed on the frame.

[0018] With this configuration, the inspection unit can be located away from the wiring circuit board without needing to provide a separate section for the inspection unit, by utilizing the frame that supports the wiring circuit board.

[0019] The present invention [7] includes the assembled sheet of [6], wherein the frame has a metal layer made of the first metal, and the inspection portion is separated from the metal layer of the frame.

[0020] In this configuration, the inspection section is separated from the metal layer of the frame, just as the second terminal is separated from the metal support layer.

[0021] Therefore, the structure of the inspection part can be made more similar to the structure of the second terminal.

[0022] The present invention [8] includes the aggregate sheet of [6] above, in which the frame has a metal layer made of the first metal, and the inspection part is continuous with the metal layer of the frame.

[0023] According to such a configuration, the inspection part can be easily formed.

[0024] The present invention [9] is a method for manufacturing an aggregate sheet according to any one of [1] to [8] above, including a first patterning step of sequentially forming the insulating layer and the first terminal on a metal foil made of the first metal, a second patterning step of etching a part of the metal foil to form the terminal body of the second terminal, and a plating step of simultaneously forming the coating layer of the second terminal and the second layer of the inspection part by plating.

[0025] According to such a method, the inspection part can be formed from the same material as the second terminal and with the same layer configuration as the second terminal.

[0026] The present invention

[10] includes the method for manufacturing an aggregate sheet of [9] above, in which the aggregate sheet further has a frame for supporting the wiring circuit board, the inspection part is arranged on the frame, the frame has a metal layer made of the first metal, and in the second patterning step, by etching a part of the metal foil, the first layer of the inspection part is separated from the metal layer of the frame.

[0027] According to such a method, the inspection part can be separated from the metal layer of the frame, and the structure of the inspection part can be made more similar to the structure of the second terminal.

Effect of the Invention

[0028] According to the aggregate sheet of the present invention, the quality inspection of the wiring circuit board can be carried out without destroying the second terminal. [Brief explanation of the drawing]

[0029] [Figure 1] Figure 1 is a plan view of an aggregate sheet as one embodiment of the present invention. [Figure 2] Figure 2A is a cross-sectional view of the aggregate sheet shown in Figure 1, section AA. Figure 2B is a cross-sectional view of the aggregate sheet shown in Figure 1, section BB. [Figure 3] Figures 3A to 3C are explanatory diagrams illustrating the first pattern step of the manufacturing method of the aggregate sheet shown in Figure 1. Figure 3A shows the step of preparing the metal foil, Figure 3B shows the step of forming a base insulating layer and a frame insulating layer on the metal foil, and Figure 3C shows the step of forming the terminal body of the first terminal and the first wiring on the base insulating layer on the metal foil, and forming the power supply section on the frame insulating layer. [Figure 4] Figures 4A to 4C are explanatory diagrams, following Figure 3C, for explaining the manufacturing method of the aggregate sheet shown in Figure 1. Figure 4A shows the second patterning process, Figure 4B shows the first plating process, and Figure 4C shows the second plating process. [Figure 5] Figure 5 is an explanatory diagram for explaining the modified example (1). [Figure 6] Figure 6 is an explanatory diagram for explaining the modified example (2). [Figure 7] Figures 7A and 7B are explanatory diagrams illustrating the plating process of the manufacturing method of the aggregate sheet shown in Figure 6. Figure 7A shows the process of forming a coating layer on the terminal body of the first terminal, forming a coating layer on the terminal body of the second terminal, and forming a second layer on the first layer of the inspection section. Figure 7B shows the process of forming another coating layer on the coating layer of the first terminal, forming a second coating layer on the coating layer of the second terminal, and forming a third layer on the second layer of the inspection section. [Figure 8] Figure 8 is an explanatory diagram for explaining modification (3). [Modes for carrying out the invention]

[0030] 1. Collective Sheet As shown in Figure 1, the assembled sheet 1 has a sheet shape that extends in a first direction and a second direction. The second direction is perpendicular to the first direction. The assembled sheet 1 comprises a plurality of wiring circuit boards 2, a frame 3, and an inspection section 4.

[0031] (1) Wiring circuit board Multiple wiring circuit boards 2 are arranged with spacing between them in a first direction and also with spacing between them in a second direction. Each of the multiple wiring circuit boards 2 has the same structure. Therefore, we will describe one of the multiple wiring circuit boards 2 and omit the descriptions of the other wiring circuit boards 2.

[0032] The wiring circuit board 2 extends in a first direction and a second direction. In this embodiment, the wiring circuit board 2 has a substantially rectangular shape. However, the shape of the wiring circuit board 2 is not limited.

[0033] As shown in Figures 2A and 2B, the wiring circuit board 2 comprises a metal support layer 21 (see Figure 2B), a base insulating layer 22 as an example of an insulating layer, a first conductor pattern 23, a second conductor pattern 24, and a cover insulating layer 25.

[0034] (1-1) Metal support layer The metal support layer 21 supports the base insulating layer 22, the first conductor pattern 23, and the cover insulating layer 25. The metal support layer 21 is made of a first metal. Examples of the first metal include stainless steel and copper alloys.

[0035] The thickness of the metal support layer 21 is, for example, 10 μm or more, preferably 15 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0036] (1-2) Base insulating layer The base insulating layer 22 is positioned on one side of the metal support layer 21 in the thickness direction of the assembled sheet 1. In other words, the metal support layer 21 is positioned on the other side of the base insulating layer 22 in the thickness direction. The thickness direction is perpendicular to the first and second directions. More specifically, the base insulating layer 22 is positioned on one surface of the metal support layer 21 in the thickness direction. The base insulating layer 22 is positioned between the metal support layer 21 and the first conductor pattern 23, and between the first conductor pattern 23 and the second conductor pattern 24 in the thickness direction. The base insulating layer 22 insulates the metal support layer 21 from the first conductor pattern 23. The base insulating layer 22 also insulates the first conductor pattern 23 from the second conductor pattern 24. The base insulating layer 22 is made of resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. The base insulating layer 22 has via holes 22A (see Figure 2B).

[0037] The thickness of the base insulating layer 22 is, for example, 1 μm or more, preferably 3 μm or more, and for example, 30 μm or less, preferably 15 μm or less.

[0038] (1-3) First conductor pattern The first conductor pattern 23 is positioned on one side of the base insulating layer 22 in the thickness direction. More specifically, the first conductor pattern 23 is positioned on one surface of the base insulating layer 22 in the thickness direction. The first conductor pattern 23 is positioned on the opposite side of the base insulating layer 22 from the metal support layer 21 and the second conductor pattern 24 in the thickness direction. The shape of the first conductor pattern 23 is not limited.

[0039] In this embodiment, as shown in Figure 1, the first conductor pattern 23 has a plurality of first terminals 231A, 231B, 231C, a plurality of first terminals 232A, 232B, 232C, 232D, and a plurality of first wires 233A, 233B, 233C, 233D. The number of first terminals and the number of first wires are not limited.

[0040] (1-3-1) 1st terminal The first terminals 231A, 231B, and 231C are located at one end of the wiring circuit board 2 in the second direction. In this embodiment, the first terminals 231A, 231B, and 231C are spaced apart from each other and arranged in the first direction. Each of the first terminals 231A, 231B, and 231C has, for example, a corner land shape. As shown in Figure 2A, the first terminals 231A, 231B, and 231C are located on one side of the base insulating layer 22 in the thickness direction. More specifically, the first terminals 231A, 231B, and 231C are located on one surface of the base insulating layer 22 in the thickness direction.

[0041] The width W1 of each of the first terminals 231A, 231B, and 231C is, for example, 20 μm or more, preferably 25 μm or more, and for example, 100 μm or less, preferably 50 μm or less.

[0042] The first terminal 231A has a terminal body 2311 and two coating layers 2312A and 2312B. Alternatively, the first terminal 231A may have one coating layer 2312.

[0043] The terminal body 2311 is the main body portion of the first terminal 231A. The terminal body 2311 is arranged on one surface of the base insulating layer 22 in the thickness direction. The terminal body 2311 is made of metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical properties, copper is preferred.

[0044] The thickness of the terminal body 2311 is, for example, 3 μm or more, preferably 5 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0045] Coating layer 2312A covers the terminal body 2311. Coating layer 2312B covers coating layer 2312A. Coating layers 2312A and 2312B suppress corrosion of the terminal body 2311. Each of coating layers 2312A and 2312B is made of metal. Examples of metals include nickel, gold, and tin.

[0046] In this embodiment, each of the coating layers 2312A and 2312B is made of a different metal than the metal of the terminal body 2311. Furthermore, each of the coating layers 2312A and 2312B is made of a different metal from each other. Specifically, coating layer 2312A is made of nickel, and coating layer 2312B is made of gold.

[0047] The sum of the thicknesses of coating layer 2312A and coating layer 2312B is thinner than the thickness of the terminal body 2311. The sum of the thicknesses of coating layer 2312A and coating layer 2312B is, for example, 0.1 μm or more, preferably 0.2 μm or more, and for example, 5 μm or less, preferably 4 μm or less.

[0048] The explanation for terminals 231B and 231C is the same as the explanation for terminal 231A. Therefore, the explanation for terminals 231B and 231C is omitted.

[0049] As shown in Figure 1, the first terminals 232A, 232B, 232C, and 232D are located at the other end of the wiring circuit board 2 in the second direction. In this embodiment, the first terminals 232A, 232B, 232C, and 232D are spaced apart from each other and arranged in the first direction. Each of the first terminals 232A, 232B, 232C, and 232D has, for example, a corner land shape.

[0050] The explanation for terminals 232A, 232B, 232C, and 232D is the same as the explanation for terminal 231A. Therefore, the explanation for terminals 232A, 232B, 232C, and 232D is omitted.

[0051] (1-3-2) 1st wiring One end of the first wiring 233A is connected to the first terminal 231A. The other end of the first wiring 233A is connected to the first terminal 232A. The first wiring 233A electrically connects the first terminal 231A and the first terminal 232A.

[0052] One end of the first wiring 233B is connected to the first terminal 231B. The other end of the first wiring 233B is connected to the first terminal 232B. The first wiring 233B electrically connects the first terminal 231B and the first terminal 232B.

[0053] One end of the first wiring 233C is connected to the first terminal 231C. The other end of the first wiring 233C is connected to the first terminal 232C. The first wiring 233C electrically connects the first terminal 231C and the first terminal 232C.

[0054] One end of the first wiring 233D connects to the second wiring 242 of the second conductor pattern 24 through the via hole 22A. The other end of the first wiring 233D connects to the first terminal 232D. The first wiring 233D electrically connects the second conductor pattern 24 and the first terminal 232D.

[0055] The first wirings 233A, 233B, 233C, and 233D are made of the same material as the terminal body 2311 described above.

[0056] The thickness of each of the first wirings 233A, 233B, 233C, and 233D is, for example, 3 μm or more, preferably 5 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0057] (1-4) Second conductor pattern As shown in Figures 2A and 2B, the second conductor pattern 24 is positioned on the other side of the base insulating layer 22 in the thickness direction. More specifically, the second conductor pattern 24 is positioned on the other surface of the base insulating layer 22 in the thickness direction. The second conductor pattern 24 is positioned away from the metal support layer 21. The shape of the second conductor pattern 24 is not limited.

[0058] In this embodiment, as shown in Figure 1, the second conductor pattern 24 has a second terminal 241 and a second wiring 242.

[0059] (1-4-1) 2nd terminal The second terminal 241 is located at one end of the wiring circuit board 2 in the second direction. The second terminal 241 has, for example, a square land shape. As shown in Figure 2A, the second terminal 241 is located on the other side of the base insulating layer 22 in the thickness direction. More specifically, the second terminal 241 is located on the other surface of the base insulating layer 22 in the thickness direction. The second terminal 241 is located away from the metal support layer 21.

[0060] The width W2 of the second terminal 241 is, for example, 20 μm or more, preferably 25 μm or more, and for example, 100 μm or less, preferably 50 μm or less.

[0061] The second terminal 241 has a terminal body 2411 and a covering layer 2412.

[0062] The terminal body 2411 is the main body portion of the second terminal 241. The terminal body 2411 is positioned on the other side of the base insulating layer 22 in the thickness direction. The terminal body 2411 is made of the first metal described above. In other words, the terminal body 2411 is made of the same material as the metal support layer 21.

[0063] The thickness of the terminal body 2411 is, for example, 10 μm or more, preferably 15 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0064] The coating layer 2412 covers the terminal body 2411. The coating layer 2412 also covers the second wiring 242 (see Figure 2B). The coating layer 2412 suppresses corrosion of the terminal body 2411. The coating layer 2412 is made of a second metal. This second metal is different from the first metal described above. Examples of the second metal include nickel, gold, and tin. Specifically, the coating layer 2412 is made of gold.

[0065] The thickness of the coating layer 2412 is thinner than the thickness of the terminal body 2411. The thickness of the coating layer 2412 is, for example, 0.1 μm or more, preferably 0.2 μm or more, and for example, 5 μm or less, preferably 4 μm or less.

[0066] (1-4-2)Second wiring As shown in Figure 1, one end of the second wire 242 is connected to the second terminal 241. The other end of the second wire 242 is connected to the first wire 233D of the first conductor pattern 23. The second wire 242 electrically connects the second terminal 241 and the first wire 233D. The second wire 242 is made of the same material as the terminal body 2411 described above.

[0067] The thickness of the second wiring 242 is, for example, 10 μm or more, preferably 15 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0068] (1-5) Cover insulating layer The cover insulating layer 25 covers the first wirings 233A, 233B, 233C, and 233D. In the thickness direction, the cover insulating layer 25 is arranged on one side of the base insulating layer 22. The cover insulating layer 25 does not cover the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D. The cover insulating layer 25 is made of resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester.

[0069] (2) Frame Frame 3 is positioned around the outer periphery of the assembly sheet 1. Frame 3 surrounds multiple wiring circuit boards 2. In this embodiment, frame 3 has a frame shape. Specifically, frame 3 has a first frame 3A, a second frame 3B, a third frame 3C, and a fourth frame 3D.

[0070] The first frame 3A is positioned at one end of the aggregate sheet 1 in the first direction. The first frame 3A extends in the second direction.

[0071] The second frame 3B is positioned at the other end of the assembly sheet 1 in the first direction. The second frame 3B is positioned away from the first frame 3A in the first direction. Multiple wiring circuit boards 2 are positioned between the first frame 3A and the second frame 3B in the first direction. The second frame 3B extends in the second direction.

[0072] The third frame 3C is positioned at one end of the aggregate sheet 1 in the second direction. The third frame 3C extends in the first direction. One end of the third frame 3C in the first direction connects to one end of the first frame 3A in the second direction. The other end of the third frame 3C in the first direction connects to one end of the second frame 3B in the second direction.

[0073] The fourth frame 3D is positioned at the other end of the assembly sheet 1 in the second direction. The fourth frame 3D is positioned away from the third frame 3C in the second direction. Multiple wiring circuit boards 2 are positioned between the third frame 3C and the fourth frame 3D in the second direction. The fourth frame 3D extends in the first direction. One end of the fourth frame 3D in the first direction connects to the other end of the first frame 3A in the second direction. The other end of the fourth frame 3D in the first direction connects to the other end of the second frame 3B in the second direction.

[0074] In this embodiment, the assembly sheet 1 has notches 5 between the frame 3 and the wiring circuit board 2, and between two wiring circuit boards 2. The assembly sheet 1 also has a connecting portion 6A that connects the frame 3 and the wiring circuit board 2, and a connecting portion 6B that connects two wiring circuit boards 2 to each other. Multiple wiring circuit boards 2 are connected to each other by the connecting portion 6B and then connected to the frame 3 by the connecting portion 6A. In this way, the frame 3 supports multiple wiring circuit boards 2.

[0075] As shown in Figure 2A, the frame 3 has a metal layer 31, an insulating layer 32, and a power supply section 33.

[0076] The metal layer 31 is made of the first metal described above. In other words, the metal layer 31 is made of the same metal as the metal support layer 21 of the wiring circuit board 2. The metal layer 31 has through holes 31A.

[0077] The insulating layer 32 is positioned on one side of the metal layer 31 in the thickness direction. In other words, the metal layer 31 is positioned on the other side of the insulating layer 32 in the thickness direction. More specifically, the insulating layer 32 is positioned on one surface of the metal layer 31 in the thickness direction. The insulating layer 32 is made of the same material as the base insulating layer 22 of the wiring circuit board 2. The insulating layer 32 has via holes 32A.

[0078] The power supply unit 33 is positioned on one side of the insulating layer 32 in the thickness direction. More specifically, the power supply unit 33 is positioned on one surface of the insulating layer 32 in the thickness direction. The power supply unit 33 is made of the same material as the terminal body 2311 of the first terminal 231A of the wiring circuit board 2. The power supply unit 33 is connected to the inspection unit 4 through the via hole 32A.

[0079] (3) Inspection Department As shown in Figure 1, the inspection unit 4 is positioned away from the multiple wiring circuit boards 2. The inspection unit 4 is positioned on the frame 3. As shown in Figure 2A, the inspection unit 4 is positioned on the other side of the insulating layer 32 in the thickness direction. More specifically, the inspection unit 4 is positioned on the other surface of the insulating layer 32 in the thickness direction. The inspection unit 4 is positioned within the through hole 31A. The inspection unit 4 is positioned away from the metal layer 31 of the frame 3.

[0080] The shape of the inspection unit 4 is not limited. As shown in Figure 1, in this embodiment, the inspection unit 4 has a different shape from the second terminal 241 of the wiring circuit board 2. The inspection unit 4 may have the same shape as the second terminal 241 of the wiring circuit board 2. Specifically, in this embodiment, the inspection unit 4 has a circular shape. The inspection unit 4 may also be rectangular or square.

[0081] The width W3 of at least a portion of the inspection section 4 is, for example, 30 μm or more, preferably 50 μm or more.

[0082] If the width W3 of at least a portion of the inspection section 4 is greater than or equal to the above lower limit, the "inspection of the adhesion of the coating layer 2412 to the terminal body 2411" and the "inspection of the thickness of the coating layer 2412" described later can be performed stably.

[0083] The total width of the inspection section 4 is, for example, 100 μm or less, preferably 80 μm or less.

[0084] The total width of the inspection section 4 may be greater than or less than the width W2 of the second terminal 241. If the width W2 of the second terminal 241 is small (for example, less than 50 μm), preferably, the width W3 of at least a portion of the inspection section 4 is greater than the width W2 of the second terminal 241.

[0085] The inspection unit 4 has the same layer structure and is made of the same material as the second terminal 241 of the wiring circuit board 2. More specifically, the inspection unit 4 has a first layer 41 and a second layer 42.

[0086] The first layer 41 is made of the first metal. In other words, the first layer 41 is made of the same material as the terminal body 2411 of the second terminal 241 of the wiring circuit board 2.

[0087] The thickness of the first layer 41 is substantially the same as the thickness of the terminal body 2411 of the second terminal 241 of the wiring circuit board 2. "Substantially the same" means not only that there is absolutely no difference in dimensions between them, but also that even if there is a difference in dimensions within the range of acceptable dimensional tolerances as described in the quality inspection later, they are considered to be the "same" dimensions. The thickness of the first layer 41 is, for example, 10 μm or more, preferably 15 μm or more, and for example, 50 μm or less, preferably 30 μm or less.

[0088] The second layer 42 covers the first layer 41. The second layer 42 is made of a second metal. In other words, the second layer 42 is made of the same material as the covering layer 2412 of the second terminal 241 of the wiring circuit board 2.

[0089] The thickness of the second layer 42 is substantially the same as the thickness of the covering layer 2412 of the second terminal 241 of the wiring circuit board 2. The thickness of the second layer 42 is, for example, 0.1 μm or more, preferably 0.2 μm or more, and for example, 5 μm or less, preferably 4 μm or less.

[0090] 2. Manufacturing method of aggregate sheet 1 Next, we will explain how to manufacture the aggregate sheet 1.

[0091] As shown in Figures 3A to 4C, the manufacturing method for the aggregate sheet 1 includes a first pattern step (see Figures 3A to 3C), a second pattern step (see Figure 4A), a first plating step (see Figure 4B), and a second plating step (see Figure 4C).

[0092] (1) First pattern process As shown in Figure 3A, in the first patterning step, a metal foil M made of a first metal is first prepared.

[0093] Next, as shown in Figure 3B, a base insulating layer 22 and an insulating layer 32 are formed on the metal foil M.

[0094] In detail, to form the base insulating layer 22 and the insulating layer 32, first, a photosensitive resin solution (varnish) is applied to the metal foil M and dried to form a photosensitive resin coating. Next, the photosensitive resin coating is exposed to light and developed. This forms the base insulating layer 22 and the insulating layer 32 on the metal foil M.

[0095] Next, as shown in Figure 3C, the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, and the first wiring 233A, 233B, 233C, and 233D are formed on the base insulating layer 22, and the power supply section 33 is formed on the insulating layer 32.

[0096] In detail, to form the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wiring 233A, 233B, 233C, and 233D, and the power supply section 33, a seed layer is first formed on the surface of the base insulating layer 22 and the metal foil M. The seed layer is formed, for example, by sputtering. Examples of materials for the seed layer include chromium, copper, nickel, titanium, and alloys thereof.

[0097] Next, a plating resist is bonded onto the base insulating layer 22 and the metal foil M, and the plating resist is exposed while shielding the areas where the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wiring 233A, 233B, 233C, and 233D, and the power supply section 33 are to be formed.

[0098] Next, the exposed plating resist is developed. This removes the plating resist from the light-shielded areas, exposing the seed layer in the areas where the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wiring 233A, 233B, 233C, and 233D, and the power supply section 33 will be formed. The plating resist remains in the exposed areas, i.e., the areas where the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wiring 233A, 233B, 233C, and 233D, and the power supply section 33 will not be formed.

[0099] Next, the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wiring 233A, 233B, 233C, and 233D, and the power supply section 33 are formed on the exposed seed layer by electroplating. After the electroplating is completed, the plating resist is peeled off. Then, the seed layer that was covered by the plating resist is removed by etching. As a result, the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, and the first wiring 233A, 233B, 233C, and 233D are formed on the base insulating layer 22, and the power supply section 33 is formed on the insulating layer 32.

[0100] Next, a cover insulating layer 25 (see Figures 1 and 2B) is formed on the base insulating layer 22 and the first wirings 233A, 233B, 233C, and 233D in the same manner as the formation of the base insulating layer 22.

[0101] With this, the first pattern process is completed.

[0102] (2) Second pattern process Next, as shown in Figure 4A, in the second pattern step, a portion of the metal foil M is etched to form the metal support layer 21 (see Figure 2B), the terminal body 2411 of the second terminal 241, the second wiring 242 (see Figure 2B), the metal layer 31, and the first layer 41 of the inspection section 4.

[0103] More specifically, in the second pattern process, a dry film resist is first applied to the metal foil M.

[0104] Next, the dry film resist is exposed and developed to form an etching resist. The etching resist covers the portion of the metal foil M that will become the metal support layer 21, the portion that will become the terminal body 2411 of the second terminal 241, the portion that will become the second wiring 242, and the portion that will become the metal layer 31.

[0105] Next, the portion of the metal foil M exposed from the etching resist is etched with an etching solution.

[0106] As a result, the portion of the metal foil M exposed from the etching resist is removed, forming the metal support layer 21, the terminal body 2411 of the second terminal 241, the second wiring 242, the metal layer 31, and the first layer 41 of the inspection section 4. In other words, in the second patterning process, the first layer 41 of the inspection section 4 is separated from the metal layer 31 of the frame 3 by etching a portion of the metal foil M.

[0107] After that, the etching resist is removed.

[0108] (3) First plating process Next, as shown in Figure 4B, in the first plating process, the coating layer 2412 of the second terminal 241 and the second layer 42 of the inspection section 4 are formed simultaneously by plating.

[0109] More specifically, a plating resist is bonded onto the metal foil M so that the terminal body 2411 of the second terminal 241, the second wiring 242, and the first layer 41 of the inspection section 4 are exposed, and the metal support layer 21 and the metal layer 31 are covered. In addition, a plating resist is bonded onto the base insulating layer 22 so that the terminal bodies 2311 of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the first wirings 233A, 233B, 233C, and 233D, and the power supply section 33 are covered.

[0110] Next, a coating layer 2412 is formed on the terminal body 2411 and the second wiring 242 by electroplating, and a second layer 42 is formed on the first layer 41.

[0111] At this time, power is supplied to the terminal body 2411 and the second wiring 242 through plated leads (not shown) and the first wiring 233D (see Figure 2B). Power is also supplied to the first layer 41 through plated leads (not shown) and the power supply unit 33.

[0112] After that, the plating resist is removed.

[0113] (4) Second plating process Next, as shown in Figure 4C, in the second plating process, coating layers 2312A and 2312B are sequentially formed on the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D by plating.

[0114] Specifically, a plating resist is bonded onto the base insulating layer 22 so that the terminal bodies 2311 of each of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D are exposed and the power supply section 33 is covered. In addition, a plating resist is bonded onto the metal foil M so that the metal support layer 21, the second conductor pattern 24, the metal layer 31, and the inspection section 4 are covered.

[0115] Next, coating layers 2312A and 2312B are sequentially formed on the terminal body 2311 by electroplating.

[0116] Subsequently, the plating resist is removed. This completes the production of aggregate sheet 1.

[0117] 3. How to use the inspection unit Next, we will explain how to use the inspection unit 4.

[0118] The inspection unit 4 is used for quality inspection of the second conductor pattern 24 of the manufactured assembly sheet 1. Examples of quality inspections include inspection of the adhesion of the coating layer 2412 to the terminal body 2411, and inspection of the thickness of the coating layer 2412.

[0119] (1) Inspection of the adhesion of the coating layer 2412 to the terminal body 2411 To inspect the adhesion of the coating layer 2412 to the terminal body 2411, for example, a peel test as specified in JIS H 8504:1999 (Test method for adhesion of plating) is performed on the second layer 42 of the inspection section 4.

[0120] As described above, the coating layer 2412 is formed simultaneously with the second layer 42 in the first plating process. Therefore, the second terminal 241 has a layer structure consisting of a layer made of the first metal (terminal body 2411) and a layer made of the second metal (coating layer 2412), and the inspection section 4 also has a layer structure consisting of a layer made of the first metal (first layer 41) and a layer made of the second metal (second layer 42). In other words, the inspection section 4 has the same layer structure made of the same material as the second terminal 241.

[0121] Therefore, the adhesion of the coating layer 2412 to the terminal body 2411 is the same as, or approximates, the adhesion of the second layer 42 to the first layer 41. "Approximate" means that they are similar enough to be considered the same quality in quality inspections.

[0122] Therefore, by inspecting the adhesion of the second layer 42 to the first layer 41, the adhesion of the coating layer 2412 to the terminal body 2411 can be estimated.

[0123] (2) Inspection of the thickness of the coating layer 2412 To inspect the thickness of the coating layer 2412, for example, the thickness of the second layer 42 of the inspection section 4 is measured using X-ray fluorescence analysis.

[0124] As described above, the coating layer 2412 is formed simultaneously with the second layer 42 in the first plating process. Therefore, the thickness of the coating layer 2412 is substantially the same as the thickness of the second layer 42.

[0125] Therefore, by inspecting the thickness of the second layer 42, the thickness of the coating layer 2412 can be estimated.

[0126] 4. Effects (1) According to the assembled sheet 1, as shown in Figure 2A, the second terminal 241 of the wiring circuit board 2 has a layer structure consisting of a layer made of a first metal (terminal body 2411) and a layer made of a second metal (covering layer 2412). The inspection unit 4, which is located away from the wiring circuit board 2, also has a layer structure consisting of a layer made of a first metal (first layer 41) and a layer made of a second metal (second layer 42). In other words, the inspection unit 4 has the same layer structure made of the same material as the second terminal 241.

[0127] Therefore, the quality of the second terminal 241 can be estimated based on the results of the quality inspection performed on the inspection unit 4.

[0128] As a result, the inspection unit 4 can be used to perform quality inspection on the wiring circuit board 2 without damaging the second terminal 241.

[0129] (2) According to the aggregate sheet 1, as shown in Figure 2A, the width W3 of at least a part of the inspection section 4 is 30 μm or more.

[0130] Therefore, the size of the inspection unit 4 can be secured, and quality inspections using the inspection unit 4 can be easily performed.

[0131] (3) According to the assembled sheet 1, as shown in Figure 1, the inspection unit 4 is arranged on the frame 3.

[0132] Therefore, by utilizing the frame 3 that supports the wiring circuit board 2, the inspection unit 4 can be installed at a location away from the wiring circuit board 2 without having to provide a separate section for the inspection unit 4.

[0133] (4) According to the assembled sheet 1, as shown in Figure 2A, the second terminal 241 is separated from the metal support layer 21, and similarly, the inspection section 4 is separated from the metal layer 31 of the frame 3.

[0134] Therefore, the structure of the inspection unit 4 can be made to more closely resemble the structure of the second terminal 241.

[0135] (5) According to the manufacturing method of the aggregate sheet 1, as shown in Figure 4B, In the first plating process, the coating layer 2412 of the second terminal 241 and the second layer 42 of the inspection section 4 are formed simultaneously by plating.

[0136] Therefore, the inspection section 4 can be formed from the same material as the second terminal 241 and with the same layer configuration as the second terminal 241.

[0137] (6) According to the manufacturing method of the aggregate sheet 1, as shown in Figure 4A, in the second pattern step, the first layer 41 of the inspection section 4 is separated from the metal layer 31 of the frame 3 by etching a part of the metal foil M.

[0138] This method allows the inspection unit 4 to be separated from the metal layer 31 of the frame 3, and the structure of the inspection unit 4 can be made to more closely resemble the structure of the second terminal 241.

[0139] 5. Variations Next, a modified example will be described with reference to Figures 5 to 8. 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.

[0140] (1) As shown in Figure 5, the inspection section 4 may be continuous with the metal layer 31 of the frame 3. Specifically, the first layer 41 of the inspection section 4 may be continuous with the metal layer 31 of the frame 3. The frame 3 does not need to have an insulating layer 32 and a power supply section 33.

[0141] According to this modified example, the inspection section 4 can be easily formed.

[0142] In more detail, it is not necessary to form the insulating layer 32 and the power supply section 33 on the metal foil M in the first patterning process.

[0143] Furthermore, in the second pattern process, it is not necessary to form through holes 31A in the metal layer 31.

[0144] Then, in the first plating process, the terminal body 2411 of the second terminal 241, the second wiring 242, and a portion of the metal layer 31 (the portion that will become the first layer 41 of the inspection section 4) are exposed, and the remaining portion of the metal support layer 21 and the metal layer 31 (the portion that does not form the inspection section 4) is covered with a plating resist.

[0145] Next, power is supplied to the metal layer 31, and a second layer 42 is formed on a portion of the metal layer 31 (the portion exposed from the plating resist) by electroplating.

[0146] Otherwise, the aggregate sheet 1 can be manufactured in the same manner as the embodiment described above.

[0147] (2) As shown in Figure 6, the second terminal may further have a second coating layer 2413 that covers the coating layer 2412. In this case, the inspection unit 4 has a third layer 43 that covers the second layer 42. The second coating layer 2413 and the third layer 43 are made of a third metal. Examples of the third metal include nickel, gold, and tin. The third metal is different from both the first and second metals. Specifically, the second metal is nickel and the third metal is gold.

[0148] According to this modified example, instead of the first and second plating steps of the embodiment described above, the terminal bodies 2311 of each of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the terminal body 2411 of the second terminal 241, and the first layer 41 of the inspection section 4 are plated simultaneously (plating step), as shown in Figures 7A and 7B.

[0149] In detail, as shown in Figure 7A, the coating layers 2312A of the first terminals 231A, 231B, and 231C, the coating layer 2412 of the second terminal 241, and the second layer 42 of the inspection section 4 are formed simultaneously by electroplating.

[0150] Next, as shown in Figure 7B, the coating layers 2312B of the first terminals 231A, 231B, 231C, 232A, 232B, 232C, and 232D, the second coating layer 2413 of the second terminal 241, and the third layer 43 of the inspection section 4 are formed simultaneously by electroplating.

[0151] Otherwise, the aggregate sheet 1 can be manufactured in the same manner as the embodiment described above.

[0152] (3) As shown in Figure 8, the assembled sheet 1 may have multiple inspection units 4. One inspection unit 4 may be provided for one wiring circuit board. The inspection unit 4 may be located between the frame 3 and the wiring circuit board 2. [Explanation of Symbols]

[0153] 1. Collective Sheet 2 Wiring circuit board 3 frames 4. Inspection Department 21 Metal support layer 22 Base insulating layer 31 Metal layer 41 1st layer 42 2nd layer 43 3rd layer 231A 1st terminal 241 2nd terminal 2411 Terminal body 2412 Covering layer 2413 2nd coating layer M Metal foil W3 Width of the inspection section

Claims

1. The system comprises a wiring circuit board and an inspection unit located away from the wiring circuit board, The aforementioned wiring circuit board is Insulating layer and, A first terminal is positioned on one side of the insulating layer in the thickness direction, A metal support layer made of a first metal and positioned on the other side of the insulating layer in the thickness direction, On the other side of the insulating layer in the thickness direction, a second terminal is positioned away from the metal support layer. It has, The aforementioned second terminal is The terminal body made of the first metal, A coating layer that covers the terminal body, comprising a second metal different from the first metal mentioned above, and It has, The aforementioned inspection unit is A first layer made of the first metal, A second layer made of the second metal and covering the first layer A composite sheet having the following characteristics.

2. The aggregate sheet according to claim 1, wherein the second metal is gold or nickel.

3. The aforementioned second terminal is It further comprises a second coating layer that covers the coating layer, which is made of a third metal different from both the first and second metals. The aforementioned inspection unit is The aggregate sheet according to claim 1, further comprising a third layer made of the third metal and covering the second layer.

4. The second metal is nickel, The aggregate sheet according to claim 3, wherein the third metal is gold.

5. The aggregate sheet according to claim 1, wherein the width of at least a portion of the inspection section is 30 μm or more.

6. The aforementioned assembly sheet further comprises a frame that supports the wiring circuit board, The inspection unit is an aggregate sheet according to claim 1, which is arranged on the frame.

7. The frame has a metal layer made of the first metal, The assembly sheet according to claim 6, wherein the inspection section is separated from the metal layer of the frame.

8. The frame has a metal layer made of the first metal, The inspection section is continuous with the metal layer of the frame, as described in claim 6.

9. A method for manufacturing an aggregate sheet according to any one of claims 1 to 8, A first pattern step in which the insulating layer and the first terminal are sequentially formed on a metal foil made of the first metal, A second pattern step involves etching a portion of the metal foil to form the terminal body of the second terminal, A plating process in which the coating layer of the second terminal and the second layer of the inspection section are simultaneously formed by plating. A method for manufacturing aggregate sheets, including [the specified element].

10. The aforementioned assembly sheet further comprises a frame that supports the wiring circuit board, The inspection unit is arranged in the frame, The frame has a metal layer made of the first metal, The method for manufacturing an aggregate sheet according to claim 9, wherein in the second pattern step, the first layer of the inspection portion is separated from the metal layer of the frame by etching a portion of the metal foil.

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