Aggregate sheet and manufacturing method of aggregate sheet

Abstract

To provide an aggregate sheet capable of achieving an improved location accuracy of a photomask to the aggregate sheet, and to provide a manufacturing method of an aggregate sheet.SOLUTION: An aggregate sheet 1 includes a wiring circuit board 2, and a frame 3 supporting the wiring circuit board 2. The frame 3 includes an alignment mark 32. The alignment mark 32 includes a first mark 321 including a first isolation layer 3211 and a conductor layer 3212, and a second isolation layer 323. The conductor layer 3212 is disposed on the first isolation layer 3211 and includes an opening 3212A. The second isolation layer 323 is disposed on the first isolation layer 3211 and covers the conductor layer 3212.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] BACKGROUND ART Conventionally, in the manufacture of wired circuit boards, it is known to provide an alignment mark and a plurality of identification marks on an assembly sheet having a plurality of wired circuit boards (see, for example, Patent Document 1 below).

[0003] The identification mark is used to identify the photomask for each process, and the alignment mark is used to align the photomask with the assembly sheet. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-227363 Summary of the Invention [Problem to be solved by the invention]

[0005] In the method for producing a wired circuit board as described in Patent Document 1, there is a demand for further improvement in the positional accuracy of the photomask relative to the assembly sheet.

[0006] The present invention provides an assembly sheet that can improve the positional accuracy of a photomask relative to the assembly sheet, and a method for manufacturing the assembly sheet. [Means for solving the problem]

[0007] The present invention [1] includes an assembly sheet comprising a wiring circuit board and a frame having an alignment mark and supporting the wiring circuit board, wherein the alignment mark comprises a first mark consisting of a first insulating layer and a conductor layer disposed on the first insulating layer and having a first opening, and a second insulating layer disposed on the first insulating layer in the thickness direction of the first insulating layer and covering the conductor layer.

[0008] According to this configuration, the alignment mark includes a first mark made up of a first insulating layer and a conductive layer disposed on the first insulating layer, The conductive layer of the first mark has a first opening.

[0009] Therefore, the contrast between the first insulating layer and the conductive layer allows the inner peripheral edge of the first opening to be clearly recognized.

[0010] Therefore, during the manufacturing of the assembly sheet, the photomask for each process can be aligned with the assembly sheet based on the inner peripheral edge of the first opening, thereby enabling the photomask to be aligned with the assembly sheet with high precision.

[0011] As a result, the positional accuracy of the photomask relative to the assembly sheet can be improved.

[0012] Furthermore, since the conductor layer is covered with the second insulating layer, the conductor layer can be protected.

[0013] The present invention [2] includes the assembly sheet of the above [1], wherein the alignment mark further comprises a second mark arranged at a distance from the first mark and made of the same material as the first insulating layer.

[0014] According to this configuration, the second mark can be formed together with the first insulating layer of the first mark.

[0015] Therefore, the second mark can be used to align a photomask with respect to the assembly sheet, and a conductor layer can be formed on the first insulating layer.

[0016] The present invention [3] includes the assembly sheet of the above [2], wherein the alignment mark is arranged on top of the second mark in the thickness direction, and further has a third insulating layer arranged at a distance from the second insulating layer.

[0017] The present invention [4] includes the assembly sheet of any one of [1] to [3] above, wherein the frame has a metal layer, and the first insulating layer is disposed on the metal layer in the thickness direction.

[0018] The present invention [5] includes the assembly sheet of the above [4], wherein the metal layer has a second opening, and when projected in the thickness direction, the first opening is positioned within the second opening.

[0019] With this configuration, the inner peripheral edge of the first opening can be recognized through the second opening in the metal layer.

[0020] The present invention [6] includes the assembly sheet of the above [5], wherein the first insulating layer has a first portion that is positioned within the second opening when projected in the thickness direction, and a second portion that is positioned around the first portion, and the thickness of the first portion is thinner than the thickness of the second portion.

[0021] With this configuration, the thickness of the first portion disposed within the second opening is small, so that the inner peripheral edge of the first opening can be recognized through the second opening of the metal layer and the first portion of the first insulating layer.

[0022] The present invention [7] includes the assembly sheet of any one of the above [4] to [6], wherein the conductor layer is electrically connected to the metal layer.

[0023] According to this configuration, the surface of the conductor layer can be electrolessly plated using the metal layer as a reference potential.

[0024] The present invention [8] includes the assembly sheet of the above [7], in which the outer periphery of the conductor layer is electrically connected to the metal layer.

[0025] According to this configuration, the conductor layer is electrically connected to the metal layer at the outer periphery away from the inner periphery edge of the first opening.

[0026] Therefore, the surface of the conductor layer can be electrolessly plated using the metal layer as a potential reference, and after the conductor layer is formed, the inner peripheral edge of the first opening can be reliably recognized.

[0027] The present invention [9] includes the assembly sheet of any one of the above [1] to [8], wherein the alignment mark further has a fourth insulating layer disposed on the second insulating layer in the thickness direction.

[0028] The present invention

[10] includes the assembly sheet of any one of the above [2] to [9], wherein the first mark has a circular shape, and the second mark has a ring shape concentric with the first mark.

[0029] The present invention

[11] includes an assembly sheet according to any one of the above [2] to

[10] , wherein the alignment mark is arranged on the second mark in the thickness direction and further comprises a third mark made of the same material as the conductor layer.

[0030] According to this configuration, the photomask can be aligned with respect to the assembly sheet by selecting either the first mark or the third mark.

[0031] The present invention

[12] includes an assembly sheet according to any one of [1] to

[11] above, wherein the assembly sheet extends in a width direction perpendicular to the thickness direction and in a flow direction perpendicular to the thickness direction and the width direction, the frame has a plurality of the alignment marks, and the plurality of alignment marks include a first alignment mark, a second alignment mark arranged at a distance from the first alignment mark in the width direction, and a third alignment mark arranged at a distance from the second alignment mark in the flow direction.

[0032] According to this configuration, by using a plurality of alignment marks, it is possible to further improve the positional accuracy of the photomask relative to the assembly sheet.

[0033] The present invention

[13] includes the assembly sheet of the above

[12] , wherein the second alignment marks are smaller than the first alignment marks and the third alignment marks.

[0034] According to this configuration, the width direction and flow direction of the assembly sheet can be easily recognized by checking the position of the second alignment mark.

[0035] The present invention

[14] includes the assembly sheet of

[12] or

[13] above, in which the distance between the first alignment mark and the second alignment mark in the width direction is different from the distance between the second alignment mark and the third alignment mark in the flow direction.

[0036] With this configuration, the width direction and flow direction of the assembly sheet can be easily identified by checking the distance between the first alignment mark and the second alignment mark in the width direction, and the distance between the second alignment mark and the third alignment mark in the flow direction.

[0037] The present invention

[15] is a method for manufacturing an assembly sheet according to any one of the above [1] to

[14] , wherein the wired circuit board comprises a base insulating layer made of the same material as the first insulating layer, a circuit pattern arranged on the base insulating layer in the thickness direction and made of the same material as the conductor layer, and a cover insulating layer arranged on the base insulating layer in the thickness direction and made of the same material as the second insulating layer, covering the circuit pattern; and the method for manufacturing the assembly sheet includes a base insulating layer forming step of forming the first insulating layer together with the base insulating layer, a circuit pattern forming step of forming the circuit pattern on the base insulating layer and also forming the conductor layer on the first insulating layer, and a cover insulating layer forming step of forming the cover insulating layer on the base insulating layer, wherein in the cover insulating layer forming step, a photomask for forming the cover insulating layer is aligned with the circuit pattern using the first mark.

[0038] According to this method, in the circuit pattern forming step, the circuit pattern and the conductor layer are formed, and the positional relationship between the circuit pattern and the conductor layer is determined.

[0039] Then, in the cover insulating layer forming step, the first mark is used to align a photomask for forming the cover insulating layer with respect to the circuit pattern.

[0040] Therefore, the photomask for forming the cover insulating layer can be aligned with the circuit pattern based on the inner peripheral edge of the first opening, and the positional accuracy of the photomask with respect to the circuit pattern can be improved.

[0041] The present invention

[16] includes a method for manufacturing an assembly sheet according to the above

[15] , wherein in the base insulating layer forming step, the base insulating layer, the first insulating layer, and a second mark arranged at a distance from the first insulating layer and made of the same material as the first insulating layer are formed on one side of a metal substrate, and in the circuit pattern forming step, a photomask for forming the circuit pattern is aligned with the base insulating layer using the second mark.

[0042] According to this method, the insulating base layer, the first insulating layer, and the second mark are formed in the insulating base layer forming step, and the positional relationship between the insulating base layer, the first insulating layer, and the second mark is determined.

[0043] Therefore, in the circuit pattern forming step, the second mark can be used to align a photomask for forming the circuit pattern with respect to the base insulating layer.

[0044] The present invention

[17] includes the method for manufacturing an assembly sheet according to the above

[16] , wherein the method for manufacturing the assembly sheet further includes an opening formation step of forming an opening in the substrate, and in the opening formation step, the first mark is used to align a photomask for forming the opening with respect to the substrate.

[0045] According to this method, in the opening formation step, the first mark is used to align the photomask for forming the opening with respect to the substrate.

[0046] Therefore, the photomask for forming the opening can be aligned with respect to the substrate based on the inner peripheral edge of the first opening, and the positional accuracy of the photomask with respect to the substrate can be improved. [Effects of the Invention]

[0047] According to the assembly sheet and the method for manufacturing the assembly sheet of the present invention, it is possible to improve the positional accuracy of the photomask relative to the assembly sheet. [Brief explanation of the drawings]

[0048] [Figure 1] Fig. 1 is a plan view of an assembly sheet according to one embodiment of the present invention, in which the cover insulating layer, second insulating layer, and third insulating layer are omitted. [Figure 2] FIG. 2 is a cross-sectional view of the printed circuit board shown in FIG. 1 taken along the line AA. [Figure 3] FIG. 3 is an enlarged view of the alignment mark shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view of the alignment mark shown in FIG. 1 taken along the line BB. [Figure 5] FIG. 5 is a plan view of the substrate after the insulating base layer forming step. [Figure 6] Fig. 6A is a CC cross-sectional view of the substrate shown in Fig. 5. Fig. 6B is a DD cross-sectional view of the substrate shown in Fig. 5. [Figure 7] 7A and 7B are explanatory views illustrating the step of exposing a plating resist in the circuit pattern forming step, where Fig. 7A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 7B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 8] FIG. 8 is a plan view of the photomask shown in FIGS. 7A and 7B. [Figure 9] 9A and 9B are explanatory views illustrating a process of forming a conductor layer of a first mark together with a circuit pattern in a circuit pattern forming process. Fig. 9A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 9B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 10] 10A and 10B are explanatory views illustrating a step of exposing a photosensitive resin coating film in the insulating cover layer forming step, in which Fig. 10A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 10B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 11] FIG. 11 is a plan view of the photomask shown in FIGS. 10A and 10B. [Figure 12]12A and 12B are explanatory views illustrating a step of exposing an etching resist in an opening formation step, in which Fig. 12A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 12B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 13] FIG. 13 is a plan view of the photomask shown in FIGS. 12A and 12B. [Figure 14] 14A and 14B are explanatory views illustrating the step of etching the substrate in the opening formation step, where Fig. 14A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 14B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 15] 15A and 15B are explanatory views illustrating the step of etching the base insulating layer and the first insulating layer in the opening formation step, where Fig. 15A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 15B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 16] 16A and 16B are explanatory views illustrating a step of exposing the plating resist on the other side in the thickness direction in the plating step. Fig. 16A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 16B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 17] FIG. 17 is a plan view of the photomask shown in FIGS. 16A and 16B. [Figure 18] 18A and 18B are explanatory views illustrating a step of exposing the plating resist on one side in the thickness direction in the plating step. Fig. 18A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 18B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 19] FIG. 19 is a plan view of the photomask shown in FIGS. 18A and 18B. [Figure 20] 20A and 20B are explanatory views illustrating a step of forming a coating layer on the surface of a conductor layer of a terminal in a plating step, where Fig. 20A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 20B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 21]21A and 21B are explanatory views illustrating a step of exposing an etching resist in the outer shape processing step, in which Fig. 21A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 21B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 22] FIG. 22 is a plan view of the photomask shown in FIGS. 21A and 21B. [Figure 23] 23A and 23B are explanatory views illustrating the step of etching the substrate in the outer shape processing step, in which Fig. 23A shows a cross-sectional view corresponding to line AA in Fig. 1, and Fig. 23B shows a cross-sectional view corresponding to line BB in Fig. 1. [Figure 24] FIG. 24 is a plan view of the alignment mark of the modified example (1). [Figure 25] FIG. 25 is a cross-sectional view taken along the line EE of FIG. [Figure 26] FIG. 26 is a cross-sectional view of an alignment mark of the modified example (2). [Figure 27] Fig. 27A is a cross-sectional view of a printed circuit board according to Modification (3), and Fig. 27B is a cross-sectional view of an alignment mark according to Modification (3). [Figure 28] FIG. 28 is a cross-sectional view of an alignment mark of the modified example (4). DETAILED DESCRIPTION OF THE INVENTION

[0049] 1. Assembly sheet As shown in Fig. 1, the assembly sheet 1 extends in the width direction and the machine direction. The assembly sheet 1 has a sheet shape. The machine direction is perpendicular to the width direction. The assembly sheet 1 includes a plurality of wired circuit boards 2 and a frame 3.

[0050] (1) Wired circuit board The multiple wired circuit boards 2 are arranged at intervals in the width direction and also at intervals in the flow direction. Each of the multiple wired circuit boards 2 has the same structure. Therefore, only one of the multiple wired circuit boards 2 will be described, and descriptions of the other wired circuit boards 2 will be omitted.

[0051] The wired circuit board 2 extends in the width direction and the flow direction. In this embodiment, the wired circuit board 2 has a substantially rectangular shape. However, the shape of the wired circuit board 2 is not limited.

[0052] As shown in FIG. 2, the wired circuit board 2 includes a metal support layer 21, a base insulating layer 22, a circuit pattern 23, and a cover insulating layer 24.

[0053] (1-1) Metal support layer The metal support layer 21 supports the base insulating layer 22, the circuit pattern 23, and the cover insulating layer 24. Examples of materials for the metal support layer 21 include stainless steel and copper alloys. The metal support layer 21 has an opening 21A.

[0054] The opening 21A is disposed at one end in the width direction of the wired circuit board 2. The opening 21A extends in the flow direction.

[0055] (1-2) Base insulation layer The base insulating layer 22 is disposed on one side of the metal support layer 21 in the thickness direction. The thickness direction is perpendicular to the width direction and the flow direction. The base insulating layer 22 is disposed on one surface of the metal support layer 21 in the thickness direction. The base insulating layer 22 is disposed between the metal support layer 21 and the circuit pattern 23 in the thickness direction. The base insulating layer 22 insulates the metal support layer 21 from the circuit pattern 23. The base insulating layer 22 is made of a transparent resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. Preferably, the base insulating layer 22 is made of polyimide. As shown in FIG. 1, the base insulating layer 22 has an opening 22A.

[0056] The opening 22A is disposed at one end in the width direction of the wired circuit board 2. The opening 22A extends in the flow direction. The entire opening 22A communicates with the opening 21A of the metal support layer 21 (see FIG. 2).

[0057] (1-3) Circuit pattern The circuit pattern 23 is disposed on one side of the base insulating layer 22 in the thickness direction. The circuit pattern 23 is disposed on one surface of the base insulating layer 22 in the thickness direction. The circuit pattern 23 is disposed on the opposite side of the base insulating layer 22 from the metal support layer 21 in the thickness direction. The shape of the circuit pattern 23 is not limited.

[0058] 1, the circuit pattern 23 has a plurality of terminals 231A, 231B, 231C, and 231D, a plurality of terminals 232A, 232B, 232C, and 232D, and a plurality of wirings 233A, 233B, 233C, and 233D. Note that the number of terminals and the number of wirings are not limited.

[0059] (1-3-1)Terminals 231A, 231B, 231C, 231D The terminals 231A, 231B, 231C, and 231D are arranged at one end of the wired circuit board 2 in the width direction. In this embodiment, the terminals 231A, 231B, 231C, and 231D are aligned in the flow direction at intervals from one another. Each of the terminals 231A, 231B, 231C, and 231D has, for example, a square land shape.

[0060] As shown in FIG. 2, the terminal 231A is disposed on one side of the base insulating layer 22 in the thickness direction. The terminal 231A is disposed on one surface of the base insulating layer 22 in the thickness direction. Specifically, one end of the terminal 231A in the width direction is disposed within the opening 22A (see FIG. 1) of the base insulating layer 22. The other end of the terminal 231A in the width direction is disposed on one surface of the base insulating layer 22. The terminal 231A has a conductor layer 2311 and a covering layer 2312. The terminal 231A does not necessarily have to have the covering layer 2312.

[0061] The conductor layer 2311 is made of a metal. Examples of materials for the conductor layer 2311 include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical properties, copper is preferred.

[0062] The covering layer 2312 covers the surface of the conductor layer 2311. The covering layer 2312 is made of a metal different from that of the conductor layer 2311. Examples of materials for the covering layer 2312 include nickel, gold, and tin. The covering layer 2312 may be a single layer or multiple layers.

[0063] The explanation for the terminals 231B, 231C, and 231D is the same as the explanation for the terminal 231A, and therefore the explanation for the terminals 231B, 231C, and 231D will be omitted.

[0064] (1-3-2) Terminals 232A, 232B, 232C, 232D 1, the terminals 232A, 232B, 232C, and 232D are arranged at the other end of the wired circuit board 2 in the width direction. In this embodiment, the terminals 232A, 232B, 232C, and 232D are arranged in the flow direction at intervals from one another. Each of the terminals 232A, 232B, 232C, and 232D has, for example, a square land shape.

[0065] 2, the terminal 232A is disposed on one side in the thickness direction of the base insulating layer 22. The terminal 232A is disposed on one surface in the thickness direction of the base insulating layer 22. Like the terminal 231A, the terminal 232A also has a conductor layer 2311 and a covering layer 2312.

[0066] The explanation for the terminals 232B, 232C, and 232D is the same as the explanation for the terminal 232A, and therefore the explanation for the terminals 232B, 232C, and 232D will be omitted.

[0067] (1-3-3) Wiring 1, one end of the wiring 233A is connected to the terminal 231 A. The other end of the wiring 233A is connected to the terminal 232 A. The wiring 233A electrically connects the terminal 231A and the terminal 232A.

[0068] One end of the wiring 233B is connected to the terminal 231 B. The other end of the wiring 233B is connected to the terminal 232 B. The wiring 233B electrically connects the terminal 231 B and the terminal 232B.

[0069] One end of the wiring 233C is connected to the terminal 231C, and the other end of the wiring 233C is connected to the terminal 232C. The wiring 233C electrically connects the terminal 231C and the terminal 232C.

[0070] One end of the wiring 233D is connected to the terminal 231D, and the other end of the wiring 233D is connected to the terminal 232D. The wiring 233D electrically connects the terminal 231D and the terminal 232D.

[0071] The wirings 233A, 233B, 233C, and 233D are made of the same material as the conductor layer 2311 of the terminal 231A.

[0072] (1-4) Cover insulation layer As shown in FIG. 2, the cover insulating layer 24 is disposed on the base insulating layer 22 in the thickness direction. The cover insulating layer 24 covers the circuit pattern 23. Specifically, the cover insulating layer 24 covers the wirings 233A, 233B, 233C, and 233D. The cover insulating layer 24 does not cover the terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D. The cover insulating layer 24 is made of a resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester.

[0073] (2) Frame As shown in Fig. 1, the frame 3 is disposed on the outer periphery of the assembly sheet 1. The frame 3 surrounds the plurality of wired circuit boards 2. In this embodiment, the frame 3 has a frame shape. Specifically, the frame 3 has a first frame 3A, a second frame 3B, a third frame 3C, and a fourth frame 3D.

[0074] The first frame 3A is disposed at one end in the machine direction of the assembly sheet 1. The first frame 3A extends in the width direction.

[0075] The second frame 3B is disposed at the other end of the assembly sheet 1 in the flow direction. The second frame 3B is disposed apart from the first frame 3A in the flow direction. The multiple wired circuit boards 2 are disposed between the first frame 3A and the second frame 3B in the flow direction. The second frame 3B extends in the width direction.

[0076] The third frame 3C is disposed at one end of the assembly sheet 1 in the width direction. The third frame 3C extends in the flow direction. One end of the third frame 3C in the flow direction is connected to one end of the first frame 3A in the width direction. The other end of the third frame 3C in the flow direction is connected to one end of the second frame 3B in the width direction.

[0077] The fourth frame 3D is disposed at the other end of the assembly sheet 1 in the width direction. The fourth frame 3D is disposed apart from the third frame 3C in the width direction. The multiple wired circuit boards 2 are disposed between the third frame 3C and the fourth frame 3D in the width direction. The fourth frame 3D extends in the flow direction. One end of the fourth frame 3D in the flow direction is connected to the other end of the first frame 3A in the width direction. The other end of the fourth frame 3D in the flow direction is connected to the other end of the second frame 3B in the width direction.

[0078] In this embodiment, the assembly sheet 1 has notches 5 between the frame 3 and the wired circuit board 2 and between two wired circuit boards 2. The assembly sheet 1 also has connection portions 6A that connect the frame 3 and the wired circuit board 2, and connection portions 6B that connect two wired circuit boards 2 together. The multiple wired circuit boards 2 are connected to the frame 3 by connection portions 6A in a state where they are connected to each other by connection portions 6B. In this way, the frame 3 supports the multiple wired circuit boards 2.

[0079] The frame 3 has a metal layer 31 and a plurality of alignment marks 32 .

[0080] (2-1) Metal layer As shown in FIGS. 3 and 4, the metal layer 31 of the frame 3 has an opening 31A as an example of a second opening. The opening 31A has a circular shape. The opening 31A overlaps with the alignment mark 32 in the thickness direction. One opening 31A is disposed on the other side of each of the alignment marks 32 in the thickness direction. The opening 31A overlaps with a first mark 321 of the alignment mark 32 in the thickness direction. The first mark 321 will be described later.

[0081] (2-2) Multiple alignment marks As shown in FIG. 1, the plurality of alignment marks 32 include a first alignment mark 32A, a second alignment mark 32B, a third alignment mark 32C, and a fourth alignment mark 32D.

[0082] The first alignment mark 32A is arranged at one end of the first frame 3A in the width direction. The first alignment mark 32A has a circular shape.

[0083] The outer diameter R1 of the first alignment mark 32A is in the range of, for example, 100 μm to 3500 μm, or preferably 100 μm to 2000 μm.

[0084] The second alignment mark 32B is arranged at the other end of the first frame 3A in the width direction. The second alignment mark 32B is arranged away from the first alignment mark 32A in the width direction. The multiple wired circuit boards 2 are arranged between the first alignment mark 32A and the second alignment mark 32B in the width direction. The second alignment mark 32B has a circular shape. The second alignment mark 32B is smaller than the first alignment mark 32A. The outer diameter R2 of the second alignment mark 32B is smaller than the outer diameter R1 of the first alignment mark 32A.

[0085] The outer diameter R2 of the second alignment mark 32B is in the range of, for example, 90 μm to 3400 μm, or preferably 90 μm to 1900 μm.

[0086] The third alignment mark 32C is disposed at the other end of the second frame 3B in the width direction. The third alignment mark 32C is disposed away from the second alignment mark 32B in the flow direction. The multiple wired circuit boards 2 are disposed between the second alignment mark 32B and the third alignment mark 32C in the flow direction. The third alignment mark 32C has a circular shape. The outer diameter R3 of the third alignment mark 32C is the same as the outer diameter R1 of the first alignment mark 32A. In other words, the second alignment mark 32B is smaller than the first alignment mark 32A and the third alignment mark 32C. Therefore, the width direction and flow direction of the assembly sheet 1 can be easily identified by checking the position of the second alignment mark 32B. Furthermore, the distance D1 between the first alignment mark 32A and the second alignment mark 32B in the width direction is different from the distance D2 between the second alignment mark 32B and the third alignment mark 32C in the flow direction. Therefore, by checking the distance D1 between the first alignment mark 32A and the second alignment mark 32B in the width direction and the distance D2 between the second alignment mark 32B and the third alignment mark 32C in the flow direction, the width direction and flow direction of the assembly sheet 1 can be easily identified.

[0087] The fourth alignment mark 32D is arranged at one end of the second frame 3B in the width direction. The fourth alignment mark 32D is arranged at a distance from the third alignment mark 32C in the width direction. The fourth alignment mark 32D is arranged at a distance from the first alignment mark 32A in the flow direction. The fourth alignment mark 32D has a circular shape. The outer diameter R4 of the fourth alignment mark 32D is the same as the outer diameter R1 of the first alignment mark 32A.

[0088] Below, we will explain the structure of the first alignment mark 32 A. The second alignment mark 32 B, the third alignment mark 32 C, and the fourth alignment mark 32 D can be explained in the same way as the first alignment mark 32 A. Therefore, explanations of the second alignment mark 32 B, the third alignment mark 32 C, and the fourth alignment mark 32 D will be omitted.

[0089] As shown in FIG. 3, first alignment mark 32A includes first mark 321, second mark 322, second insulating layer 323 (see FIG. 4), and third insulating layer 324 (see FIG. 4).

[0090] (2-2-1) First Mark The first mark 321 is disposed at the center of the first alignment mark 32A in the radial direction of the first alignment mark 32A. The first mark 321 is disposed inside the second mark 322 in the radial direction of the first alignment mark 32A. The first mark 321 is, for example, circular. The shape of the first mark 321 is not limited. The first mark 321 may be rectangular or triangular.

[0091] 4, the first mark 321 is disposed on one side of the metal layer 31 in the thickness direction. The first mark 321 is disposed on one surface of the metal layer 31 in the thickness direction. The first mark 321 is made up of a first insulating layer 3211 and a conductor layer 3212.

[0092] The first insulating layer 3211 is disposed on one side of the metal layer 31 in the thickness direction. The first insulating layer 3211 is disposed on one surface of the metal layer 31 in the thickness direction. The first insulating layer 3211 is transparent. The first insulating layer 3211 is made of the same material as the base insulating layer 22 (see FIG. 2) of the wired circuit board 2. When the first mark 321 has a circular shape, the first insulating layer 3211 also has a circular shape. The first insulating layer 3211 has a first portion 3211A and a second portion 3211B.

[0093] The first portion 3211A is disposed in the center of the first insulating layer 3211 in the radial direction of the first alignment mark 32A. When projected in the thickness direction, the first portion 3211A is disposed within the opening 31A of the metal layer 31. The thickness of the first portion 3211A is thinner than the thickness of the second portion 3211B.

[0094] The second portion 3211B is disposed on the periphery of the first insulating layer 3211. The second portion 3211B is disposed around the first portion 3211A. The second portion 3211B is disposed outside the first portion 3211A in the radial direction of the first alignment mark 32A. The second portion 3211B is disposed between the first portion 3211A and the second mark 322 in the radial direction of the first alignment mark 32A.

[0095] The conductor layer 3212 is disposed on the first insulating layer 3211. The conductor layer 3212 is made of the same material as the circuit pattern 23 of the wired circuit board 2. When the first mark 321 is circular, the conductor layer 3212 is also circular. The outer diameter of the conductor layer 3212 is larger than the diameter of the first insulating layer 3211. The conductor layer 3212 has an opening 3212A as an example of a first opening and an outer periphery 3212B.

[0096] The opening 3212A is disposed in the center of the conductor layer 3212 in the radial direction of the first alignment mark 32A. The opening 3212A has, for example, a circular shape. The inner peripheral edge E1 of the opening 3212A has, for example, an arc shape. When projected in the thickness direction, the opening 3212A is disposed within the opening 31A of the metal layer 31 in the radial direction of the first alignment mark 32A. The inner peripheral edge E1 of the opening 3212A is disposed within the inner peripheral edge E2 of the opening 31A in the radial direction of the first alignment mark 32A. The inner peripheral edge E1 of the opening 3212A is disposed apart from the inner peripheral edge E2 of the opening 31A in the radial direction of the first alignment mark 32A. The entire inner peripheral edge E1 of the opening 3212A overlaps with the first portion 3211A of the first insulating layer 3211 in the thickness direction.

[0097] The outer periphery 3212B is arranged further outward than the second portion 3211B of the first insulating layer 3211 in the radial direction of the first alignment mark 32A. The outer periphery 3212B is arranged between the second portion 3211B of the first insulating layer 3211 and the second mark 322 in the radial direction of the first alignment mark 32A. The outer periphery 3212B is arranged on the metal layer 31. The outer periphery 3212B contacts the metal layer 31. The outer periphery 3212B is electrically connected to the metal layer 31. This allows the conductor layer 3212 to be electrically connected to the metal layer 31.

[0098] (2-2-2) Second Mark The second mark 322 is arranged on the periphery of the first alignment mark 32A. The second mark 322 is arranged at a distance from the first mark 321 in the radial direction of the first alignment mark 32A. The second mark 322 is arranged at a distance from the first insulating layer 3211 of the first mark 321 in the radial direction of the first alignment mark 32A. The second mark 322 is arranged on one side of the metal layer 31 in the thickness direction. The second mark 322 is arranged on one surface of the metal layer 31 in the thickness direction. The second mark 322 is made of the same material as the first insulating layer 3211. The second mark 322 has a ring shape concentric with the first mark 321.

[0099] (2-2-3) Second insulating layer The second insulating layer 323 is disposed on the first insulating layer 3211 in the thickness direction of the first insulating layer 3211. The second insulating layer 323 covers the conductor layer 3212. Preferably, the second insulating layer 323 covers the entire conductor layer 3212. The second insulating layer 323 covers the inner peripheral edge E1 of the opening 3212A. Preferably, the second insulating layer 323 covers the entire inner peripheral edge E1 of the opening 3212A. The second insulating layer 323 is transparent. The second insulating layer 323 is made of the same material as the cover insulating layer 24 (see FIG. 2).

[0100] (2-2-4) Third insulating layer The third insulating layer 324 is disposed on the second mark 322 in the thickness direction. The third insulating layer 324 is disposed at a distance from the second insulating layer 323 in the radial direction of the first alignment mark 32A. Between the second insulating layer 323 and the third insulating layer 324, the metal layer 31 is exposed from the second insulating layer 323 and the third insulating layer 324. The third insulating layer 324 is made of the same material as the cover insulating layer 24 (see FIG. 2).

[0101] 2. Manufacturing method of assembly sheet A method for manufacturing the assembly sheet 1 will be described with reference to FIGS. 5 to 23B.

[0102] The manufacturing method of the assembly sheet 1 includes a base insulating layer forming step (see FIGS. 5 to 6B), a circuit pattern forming step (see FIGS. 7A to 9B), a cover insulating layer forming step (see FIGS. 10A and 10B), an opening forming step (see FIGS. 12A to 15B), a plating step (see FIGS. 16A to 20B), and an exterior processing step (see FIGS. 21A to 23B).

[0103] (1) Base insulating layer formation process 5, 6A, and 6B, the base insulating layer forming step forms the base insulating layer 22 for each of the plurality of wired circuit boards 2, and the first insulating layer 3211 and second mark 322 for each of the plurality of alignment marks 32. That is, in the base insulating layer forming step, the first insulating layer 3211 and second mark 322 are formed together with the base insulating layer 22.

[0104] As shown in FIG. 6A, of the base insulating layer 22 obtained in the base insulating layer forming process, the thickness of the first portion 221 in which the opening 22A (see FIG. 2) is formed is thinner than the thickness of the second portion 222 in which the opening 22A is not formed.

[0105] More specifically, in the base insulating layer forming step, first, a photosensitive resin solution (varnish) is applied onto the substrate M and dried to form a coating film of the photosensitive resin.

[0106] Next, the photosensitive resin coating is exposed and developed. The photosensitive resin coating is subjected to gradational exposure using, for example, a photomask having a light-shielding portion, a fully transparent portion, and a semi-transparent portion. The light-shielding portion faces the portion of the photosensitive resin coating where the base insulating layer 22 is not formed. The semi-transparent portion faces the portion of the photosensitive resin coating where the first portion 221 is formed. The fully transparent portion faces the portion of the photosensitive resin coating where the second portion 222, the first insulating layer 3211, and the second mark 322 are formed.

[0107] The tonal exposure results in the insulating base layer 22 having a first portion 221 and a second portion 222.

[0108] The first portion 221 may be formed thinner than the second portion 222 by etching the insulating base layer 22.

[0109] (2) Circuit pattern formation process The circuit pattern forming step is carried out after the base insulating layer forming step.

[0110] In the circuit pattern forming process, first, a seed layer is formed in the thickness direction on one surface of the base insulating layer 22, one surface of the first insulating layer 3211, one surface of the second mark 322, and one surface of the substrate M. The seed layer is formed by, for example, sputtering. Examples of materials for the seed layer include chromium, copper, nickel, titanium, and alloys thereof.

[0111] 7A and 7B, a plating resist PR1 is attached to one surface in the thickness direction of the substrate M. The plating resist PR1 covers the base insulating layer 22, the first insulating layer 3211, and the second marks 322.

[0112] Next, the second mark 322 is used to align a photomask PM1 for forming the circuit pattern 23 with respect to the base insulating layer 22.

[0113] The photomask PM1 is disposed on one side of the plating resist PR1 in the thickness direction. The photomask PM1 faces the plating resist PR1 in the thickness direction. The photomask PM1 shields a portion of the plating resist PR1 from light.

[0114] 8, the photomask PM1 has a mask pattern M1 and multiple alignment patterns A1, A2, A3, and A4. The mask pattern M1 and the alignment patterns A1, A2, A3, and A4 block light. The photomask PM1 transmits light except for the mask pattern M1 and the alignment patterns A1, A2, A3, and A4.

[0115] Mask pattern M1 is arranged between alignment patterns A1 and A2 in the width direction. Mask pattern M1 is arranged between alignment patterns A2 and A3 in the flow direction. Mask pattern M1 consists of patterns with the same shape as circuit patterns 23 (see FIG. 1). Mask pattern M1 includes patterns with the same shape as all of circuit patterns 23.

[0116] The alignment pattern A1 is arranged on one side of the mask pattern M1 in the width direction. The alignment pattern A1 is arranged on one side of the mask pattern M1 in the flow direction. The alignment pattern A1 has the same shape as the conductor layer 3212 of the first alignment mark 32A (see FIG. 1).

[0117] The alignment pattern A2 is arranged on the other side of the mask pattern M1 in the width direction. The alignment pattern A2 is arranged on one side of the mask pattern M1 in the flow direction. The alignment pattern A2 has the same shape as the conductor layer 3212 of the second alignment mark 32B (see FIG. 1).

[0118] The alignment pattern A3 is arranged on the other side of the mask pattern M1 in the width direction. The alignment pattern A3 is arranged on the other side of the mask pattern M1 in the flow direction. The alignment pattern A3 has the same shape as the conductor layer 3212 of the third alignment mark 32C (see FIG. 1).

[0119] The alignment pattern A4 is arranged on one side of the mask pattern M1 in the width direction. The alignment pattern A4 is arranged on the other side of the mask pattern M1 in the flow direction. The alignment pattern A4 has the same shape as the conductor layer 3212 of the fourth alignment mark 32D (see FIG. 1).

[0120] When viewed from one side in the thickness direction, the base insulating layer 22 (see Figure 5) overlaps with the mask pattern M1 when the center of the second mark 322 (see Figure 5) of the first alignment mark 32A coincides with the center of the alignment pattern A1, the center of the second mark 322 (see Figure 5) of the second alignment mark 32B coincides with the center of the alignment pattern A2, the center of the second mark 322 (see Figure 5) of the third alignment mark 32C coincides with the center of the alignment pattern A3, and the center of the second mark 322 (see Figure 5) of the fourth alignment mark 32D coincides with the center of the alignment pattern A4.

[0121] This aligns the photomask PM1 with the base insulating layer 22.

[0122] The center of the second mark 322 of each alignment mark 32 is calculated, for example, from the outer peripheral edge E11 (see FIG. 3) of the second mark 322. The outer peripheral edge E11 is read, for example, by image recognition.

[0123] The center of alignment pattern A1 is calculated, for example, from the outer peripheral edge E12 (see FIG. 8) of alignment pattern A1. The outer peripheral edge E12 is read, for example, by image recognition. The centers of alignment patterns A2, A3, and A4 are calculated in the same way as the center of alignment pattern A1.

[0124] In the image recognition, preferably, one alignment mark 32 is photographed within one angle of view. The same applies to all the following steps.

[0125] Next, in the circuit pattern forming step, as shown in FIGS. 7A and 7B, the plating resist PR1 is exposed through a photomask PM1 and developed.

[0126] 9A and 9B, the portions of the plating resist PR1 that are shielded by the mask pattern M1 and the alignment patterns A1, A2, A3, and A4 are removed, exposing the seed layer in the areas where the circuit pattern 23 and the conductor layer 3212 will be formed. On the other hand, the exposed portions of the plating resist PR1, i.e., the areas where the circuit pattern 23 and the conductor layer 3212 will not be formed, remain.

[0127] Next, the circuit pattern 23 and the conductor layer 3212 are formed on the exposed seed layer by electrolytic plating. That is, in the circuit pattern formation step, the circuit pattern 23 is formed on the base insulating layer 22, and the conductor layer 3212 is formed on the first insulating layer 3211. By forming the conductor layer 3212 on the first insulating layer 3211, the above-mentioned first mark 321 is completed.

[0128] After the electrolytic plating is completed, the plating resist PR1 is stripped off, and then the seed layer exposed by the stripping of the plating resist PR1 is removed by etching.

[0129] After the circuit pattern forming step and before the cover insulating layer forming step, a nickel plating layer may be formed by electroless plating on the surfaces of the circuit pattern 23 and the conductor layer 3212. At this time, since the conductor layer 3212 is electrically connected to the metal layer 31, the potential of each conductor layer 3212 of the multiple alignment marks 32 can be made uniform via the metal layer 31. Therefore, a nickel plating layer can be formed uniformly on each conductor layer 3212 of the multiple alignment marks 32.

[0130] (3) Cover insulation layer formation process The cover insulating layer forming step is carried out after the circuit pattern forming step.

[0131] In the cover insulating layer forming process, first, as shown in Figures 10A and 10B, a photosensitive resin solution (varnish) is applied onto the circuit pattern 23, the base insulating layer 22, the first mark 321, the second mark 322, and the substrate M, and then dried to form a photosensitive resin coating film F.

[0132] Next, the photomask PM2 for forming the cover insulating layer 24 is aligned with the circuit pattern 23 using the first mark 321. The photomask PM2 is different from the photomask PM1.

[0133] The photomask PM2 is disposed on one side of the coating film F in the thickness direction. The photomask PM2 faces the coating film F in the thickness direction. The photomask PM2 shields a part of the coating film F from light.

[0134] 11, the photomask PM2 has a mask pattern M2 and multiple alignment patterns A11, A12, A13, and A14. The mask pattern M2 and the alignment patterns A11, A12, A13, and A14 block light. The photomask PM2 transmits light except for the mask pattern M2 and the alignment patterns A11, A12, A13, and A14.

[0135] The mask pattern M2 is disposed between the alignment patterns A11 and A12 in the width direction. The mask pattern M2 is disposed between the alignment patterns A12 and A13 in the flow direction. The mask pattern M2 has a light-shielding portion M21 and a light-transmitting portion M22. The alignment pattern A11 is arranged on one side of the mask pattern M2 in the width direction. The alignment pattern A11 is arranged on one side of the mask pattern M2 in the flow direction. The alignment pattern A11 has a ring shape.

[0136] The alignment pattern A12 is arranged on the other side of the mask pattern M2 in the width direction. The alignment pattern A12 is arranged on one side of the mask pattern M2 in the flow direction. The alignment pattern A12 has a ring shape. The diameter of the alignment pattern A12 is smaller than the diameter of the alignment pattern A11.

[0137] The alignment pattern A13 is arranged on the other side of the mask pattern M2 in the width direction. The alignment pattern A13 is arranged on the other side of the mask pattern M11 in the flow direction. The alignment pattern A13 has a ring shape. The diameter of the alignment pattern A13 is the same as the diameter of the alignment pattern A11.

[0138] The alignment pattern A14 is arranged on one side of the mask pattern M2 in the width direction. The alignment pattern A14 is arranged on the other side of the mask pattern M2 in the flow direction. The alignment pattern A14 has a ring shape. The diameter of the alignment pattern A14 is the same as the diameter of the alignment pattern A11.

[0139] When viewed from one side in the thickness direction, the center of the first mark 321 (see Figure 1) of the first alignment mark 32A coincides with the center of the alignment pattern A11, the center of the first mark 321 (see Figure 1) of the second alignment mark 32B coincides with the center of the alignment pattern A12, the center of the first mark 321 (see Figure 1) of the third alignment mark 32C coincides with the center of the alignment pattern A13, and the center of the first mark 321 (see Figure 1) of the fourth alignment mark 32D coincides with the center of the alignment pattern A14, and the wiring 233A, 233B, 233C, and 233D (see Figure 1) of the circuit pattern 23 overlap with the transparent portion M22 of the mask pattern M2. Terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D (see FIG. 1) of the circuit pattern 23 overlap the light-shielding portion M21.

[0140] As a result, the photomask PM2 is aligned with the circuit pattern 23.

[0141] The center of the first mark 321 of each alignment mark 32 is calculated, for example, from the inner circumferential edge E1 (see FIG. 3) of the first mark 321. The inner circumferential edge E1 is read, for example, by image recognition.

[0142] The center of the alignment pattern A11 is calculated from, for example, the outer peripheral edge E21 (see FIG. 11) of the alignment pattern A11. The outer peripheral edge E21 is read, for example, by image recognition. The centers of the alignment patterns A12, A13, and A14 are calculated in the same manner as the center of the alignment pattern A11.

[0143] Next, in the cover insulating layer forming step, as shown in FIGS. 10A and 10B, the photosensitive resin coating film F is exposed and developed through a photomask PM2.

[0144] As a result, as shown in Fig. 2, the cover insulating layer 24 is formed on the base insulating layer 22. That is, in the cover insulating layer forming step, the cover insulating layer 24 is formed on the base insulating layer 22. Furthermore, as shown in Fig. 4, the second insulating layer 323 is formed on the first mark 321, and the third insulating layer 324 is formed on the second mark 322. At this time, a ring-shaped gap 320 (see FIG. 3) is formed between the second insulating layer 323 and the third insulating layer 324 due to light blocking by the alignment pattern A11 (see FIG. 10B) of the photomask PM2. The base material M is exposed from the gap 320. Therefore, by measuring the distance between the center of the base material M exposed from the gap 320 and the center of the first mark 321, it is possible to evaluate the misalignment of the cover insulating layer 24 with respect to the circuit pattern 23. In addition, by measuring the distance between the center of the base material M exposed from the gap 320 and the center of the second mark 322, it is possible to evaluate the misalignment of the cover insulating layer 24 with respect to the base insulating layer 22.

[0145] (4) Opening formation process The opening forming step is performed after the cover insulating layer forming step.

[0146] In the opening forming step, as shown in FIGS. 12A and 12B, an etching resist PR2 is attached to the other surface of the base material M in the thickness direction.

[0147] Next, the first mark 321 is used to align the photomask PM3 for forming the opening 21A (see FIG. 2) with respect to the substrate M. The photomask PM3 is different from the photomasks PM1 and PM2.

[0148] The photomask PM3 is disposed on the other side of the etching resist PR2 in the thickness direction. The photomask PM3 faces the etching resist PR2 in the thickness direction. The photomask PM3 shields a part of the etching resist PR2 from light.

[0149] 13, the photomask PM3 has a mask pattern M3 and multiple alignment patterns A21, A22, A23, and A24. The mask pattern M3 and the alignment patterns A21, A22, A23, and A24 block light. The photomask PM3 transmits light except for the mask pattern M3 and the alignment patterns A21, A22, A23, and A24.

[0150] Mask pattern M3 is arranged between alignment patterns A21 and A22 in the width direction. Mask pattern M3 is arranged between alignment patterns A22 and A23 in the flow direction. Mask pattern M3 consists of a pattern having the same shape as the openings 21A (see FIG. 2) of metal support layer 21. Mask pattern M3 includes patterns having the same shape as all of the openings 21A.

[0151] The alignment pattern A21 is arranged on one side of the mask pattern M3 in the width direction. The alignment pattern A21 is arranged on one side of the mask pattern M3 in the flow direction. The alignment pattern A21 has the same shape as the opening 31A (see FIG. 4) in the metal layer 31 of the first alignment mark 32A (see FIG. 1).

[0152] The alignment pattern A22 is arranged on the other side of the mask pattern M3 in the width direction. The alignment pattern A22 is arranged on one side of the mask pattern M3 in the flow direction. The alignment pattern A22 has the same shape as the opening 31A in the metal layer 31 of the second alignment mark 32B (see FIG. 1).

[0153] The alignment pattern A23 is arranged on the other side of the mask pattern M3 in the width direction. The alignment pattern A23 is arranged on the other side of the mask pattern M3 in the flow direction. The alignment pattern A23 has the same shape as the opening 31A in the metal layer 31 of the third alignment mark 32C (see FIG. 1).

[0154] The alignment pattern A24 is arranged on one side of the mask pattern M3 in the width direction. The alignment pattern A24 is arranged on the other side of the mask pattern M3 in the flow direction. The alignment pattern A24 has the same shape as the opening 31A in the metal layer 31 of the fourth alignment mark 32D (see FIG. 1).

[0155] When viewed from one side in the thickness direction, the center of the first mark 321 (see Figure 1) of the first alignment mark 32A coincides with the center of the alignment pattern A21, the center of the first mark 321 (see Figure 1) of the second alignment mark 32B coincides with the center of the alignment pattern A22, the center of the first mark 321 (see Figure 1) of the third alignment mark 32C coincides with the center of the alignment pattern A23, and the center of the first mark 321 (see Figure 1) of the fourth alignment mark 32D coincides with the center of the alignment pattern A24, and the first portion 221 (see Figure 12A) of the base insulating layer 22 overlaps with the mask pattern M3.

[0156] As a result, the substrate M is aligned with the photomask PM3.

[0157] The center of the first mark 321 of each alignment mark 32 is calculated, for example, from the inner peripheral edge E1 (see FIG. 3) of the first mark 321. The inner peripheral edge E1 is read through the second insulating layer 323 (see FIG. 12B), for example, by image recognition.

[0158] The center of the alignment pattern A21 is calculated, for example, from the outer peripheral edge E31 (see FIG. 13) of the alignment pattern A21. The outer peripheral edge E31 is read, for example, by image recognition. The centers of the alignment patterns A22, A23, and A24 are calculated in the same way as the center of the alignment pattern A21.

[0159] Next, as shown in FIGS. 12A and 12B, in the opening formation step, the etching resist PR2 is exposed through a photomask PM3 and developed.

[0160] As a result, the portions of the etching resist PR2 that are shielded by the mask pattern M1 and the alignment patterns A21, A22, A23, and A24 are removed, exposing the substrate M in the areas where the openings 21A and 31A are to be formed. On the other hand, the exposed portions of the etching resist PR2, i.e., the areas where the openings 21A and 31A are not to be formed, remain.

[0161] 14A and 14B, the substrate M exposed from the etching resist PR2 is etched to form the openings 21A and 31A. That is, in the opening forming step, the openings 21A are formed in the substrate M. By forming the openings 21A and 31A, the base insulating layer 22 is exposed in the opening 21A, and the first insulating layer 3211 is exposed in the opening 31A.

[0162] Next, as shown in FIGS. 15A and 15B, the base insulating layer 22 exposed in the opening 21A and the first insulating layer 3211 exposed in the opening 31A are etched.

[0163] An opening 22A is formed in the insulating base layer 22 by etching the insulating base layer 22 exposed in the opening 21A. Furthermore, by etching the first insulating layer 3211 exposed in the opening 31A, the first portion 3211A of the first insulating layer 3211 is formed thinner than the second portion 3211B of the first insulating layer 3211. This makes it possible to read the inner peripheral edge E1 (see FIG. 3) of the opening 3212A in the conductive layer 3212 of the first mark 321 through the opening 31A and the first portion 3211A of the first insulating layer 3211, for example, by image recognition. By measuring the distance between the center of the first mark 321 and the center of the opening 31A, calculated from the inner peripheral edge E1, the positional deviation of the opening 21A (see FIG. 15A) relative to the circuit pattern 23 can be evaluated.

[0164] (5) Plating process The plating step is carried out after the opening forming step.

[0165] In the plating step, first, as shown in FIGS. 16A and 16B, a plating resist PR3 is attached to the other surface of the base material M in the thickness direction, and a plating resist PR4 is attached to one surface of the base material M in the thickness direction.

[0166] Next, a photomask PM4 for plating resist PR3 is aligned with terminals 231A, 231B, 231C, and 231D using first mark 321. Photomask PM4 is different from photomasks PM1, PM2, and PM3.

[0167] The photomask PM4 is disposed on the other side of the plating resist PR3 in the thickness direction. The photomask PM4 faces the plating resist PR3 in the thickness direction. The photomask PM4 shields a portion of the plating resist PR3 from light.

[0168] 17, the photomask PM4 has a mask pattern M4 and multiple alignment patterns A31, A32, A33, and A34. The mask pattern M4 and the alignment patterns A31, A32, A33, and A34 block light. The photomask PM4 transmits light except for the mask pattern M4 and the alignment patterns A31, A32, A33, and A34.

[0169] Mask pattern M4 is arranged between alignment patterns A31 and A32 in the width direction, and between alignment patterns A32 and A33 in the flow direction.

[0170] The alignment pattern A31 is arranged on one side of the mask pattern M4 in the width direction. The alignment pattern A31 is arranged on one side of the mask pattern M4 in the flow direction. The alignment pattern A32 is arranged on the other side of the mask pattern M4 in the width direction. The alignment pattern A32 is arranged on one side of the mask pattern M4 in the flow direction. The alignment pattern A33 is arranged on the other side of the mask pattern M4 in the width direction. The alignment pattern A33 is arranged on the other side of the mask pattern M4 in the flow direction. The alignment pattern A34 is arranged on one side of the mask pattern M4 in the width direction. The alignment pattern A34 is arranged on the other side of the mask pattern M4 in the flow direction. The alignment patterns A31, A32, A33, and A34 have circular shapes. The diameter of each of the alignment patterns A31, A32, A33, and A34 is smaller than the diameter of the opening 3212A of each alignment mark 32 (see FIG. 3).

[0171] When viewed from the other side in the thickness direction, the center of the first mark 321 (see Figure 1) of the first alignment mark 32A coincides with the center of the alignment pattern A31, the center of the first mark 321 (see Figure 1) of the second alignment mark 32B coincides with the center of the alignment pattern A32, the center of the first mark 321 (see Figure 1) of the third alignment mark 32C coincides with the center of the alignment pattern A33, and the center of the first mark 321 (see Figure 1) of the fourth alignment mark 32D coincides with the center of the alignment pattern A34, and the mask pattern M4 overlaps with the terminals 231A, 231B, 231C, and 231D (see Figure 16A).

[0172] As a result, the photomask PM4 is aligned with the terminals 231A, 231B, 231C, and 231D.

[0173] The center of the first mark 321 of each alignment mark 32 is calculated, for example, from the inner peripheral edge E1 (see FIG. 3) of the opening 3212A of the conductor layer 3212 of the first mark 321. The inner peripheral edge E1 is read, for example, by image recognition through the opening 31A (see FIG. 16A) of the metal layer 31 and the first portion 3211A (see FIG. 16A) of the first insulating layer 3211.

[0174] The center of alignment pattern A31 is calculated, for example, from outer peripheral edge E41 (see FIG. 17) of alignment pattern A31. Outer peripheral edge E41 is read, for example, by image recognition. The centers of alignment patterns A32, A33, and A34 are calculated in the same way as the center of alignment pattern A31.

[0175] Next, as shown in FIGS. 16A and 16B, in the opening formation step, the plating resist PR3 is exposed to light through a photomask PM4.

[0176] 18A and 18B, a photomask PM5 for plating resist PR4 is aligned with terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D using first mark 321. Photomask PM5 is different from photomasks PM1, PM2, PM3, and PM4.

[0177] The photomask PM5 is disposed on one side of the plating resist PR4 in the thickness direction. The photomask PM5 faces the plating resist PR4 in the thickness direction. The photomask PM5 shields a portion of the plating resist PR4 from light.

[0178] 19, the photomask PM5 has a mask pattern M5 and multiple alignment patterns A41, A42, A43, and A44. The mask pattern M5 and the alignment patterns A41, A42, A43, and A44 block light. The photomask PM5 transmits light except for the mask pattern M5 and the alignment patterns A41, A42, A43, and A44.

[0179] Mask pattern M5 is arranged between alignment patterns A41 and A42 in the width direction, and between alignment patterns A42 and A43 in the flow direction.

[0180] The alignment pattern A41 is arranged on one side of the mask pattern M5 in the width direction. The alignment pattern A41 is arranged on one side of the mask pattern M5 in the flow direction. The alignment pattern A42 is arranged on the other side of the mask pattern M5 in the width direction. The alignment pattern A42 is arranged on one side of the mask pattern M5 in the flow direction. The alignment pattern A43 is arranged on the other side of the mask pattern M5 in the width direction. The alignment pattern A43 is arranged on the other side of the mask pattern M5 in the flow direction. The alignment pattern A44 is arranged on one side of the mask pattern M5 in the width direction. The alignment pattern A44 is arranged on the other side of the mask pattern M5 in the flow direction. The alignment patterns A41, A42, A43, and A44 have circular shapes. The diameter of each of the alignment patterns A41, A42, A43, and A44 is smaller than the diameter of the opening 3212A of each alignment mark 32 (see FIG. 3).

[0181] When viewed from one side in the thickness direction, the center of the first mark 321 (see Figure 1) of the first alignment mark 32A coincides with the center of the alignment pattern A41, the center of the first mark 321 (see Figure 1) of the second alignment mark 32B coincides with the center of the alignment pattern A42, the center of the first mark 321 (see Figure 1) of the third alignment mark 32C coincides with the center of the alignment pattern A43, and the center of the first mark 321 (see Figure 1) of the fourth alignment mark 32D coincides with the center of the alignment pattern A44, and the mask pattern M5 overlaps with the terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D.

[0182] As a result, the photomask PM5 is aligned with the terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D.

[0183] The center of the first mark 321 of each alignment mark 32 is calculated, for example, from the inner peripheral edge E1 (see FIG. 3) of the first mark 321. The inner peripheral edge E1 is read through the second insulating layer 323 (see FIG. 18B), for example, by image recognition.

[0184] The center of alignment pattern A41 is calculated, for example, from outer peripheral edge E51 (see FIG. 19) of alignment pattern A41. Outer peripheral edge E51 is read, for example, by image recognition. The centers of alignment patterns A52, A53, and A54 are calculated in the same way as the center of alignment pattern A51.

[0185] Next, as shown in FIGS. 18A and 18B, in the opening formation step, the plating resist PR4 is exposed to light through a photomask PM5.

[0186] Next, as shown in Figures 20A and 20B, the plating resists PR3 and PR4 are developed. This removes the portions of the plating resist PR3 that are shielded by the mask pattern M4 and the alignment patterns A31, A32, A33, and A34, and removes the portions of the plating resist PR4 that are shielded by the mask pattern M5 and the alignment patterns A41, A42, A43, and A44. This exposes the terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D.

[0187] Next, the covering layer 2312 is formed on the terminals 231A, 231B, 231C, 231D, 232A, 232B, 232C, and 232D by electrolytic plating or electroless plating.

[0188] Thereafter, the plating resists PR3 and PR4 are stripped off.

[0189] (6) External shape processing process The contour processing step is carried out after the plating step.

[0190] In the outer shape processing step, as shown in FIGS. 21A and 21B, an etching resist PR5 is attached to the other surface of the base material M in the thickness direction.

[0191] Next, the first mark 321 is used to align the photomask PM6 for outer shape processing with respect to the base material M. The photomask PM6 is different from the photomasks PM1, PM2, PM3, PM4, and PM5.

[0192] The photomask PM6 is disposed on the other side of the etching resist PR5 in the thickness direction. The photomask PM6 faces the etching resist PR5 in the thickness direction. The photomask PM6 shields a part of the etching resist PR5 from light.

[0193] 22, the photomask PM6 has a mask pattern M6 and multiple alignment patterns A51, A52, A53, and A54. The mask pattern M6 and the alignment patterns A51, A52, A53, and A54 block light. The photomask PM6 transmits light except for the mask pattern M6 and the alignment patterns A51, A52, A53, and A54.

[0194] Mask pattern M6 is arranged between alignment patterns A51 and A52 in the width direction. Mask pattern M6 is arranged between alignment patterns A52 and A53 in the flow direction. Mask pattern M6 has a pattern with the same shape as opening 5 (see FIG. 1).

[0195] The alignment pattern A51 is arranged on one side of the mask pattern M6 in the width direction. The alignment pattern A51 is arranged on one side of the mask pattern M6 in the flow direction. The alignment pattern A52 is arranged on the other side of the mask pattern M6 in the width direction. The alignment pattern A52 is arranged on one side of the mask pattern M6 in the flow direction. The alignment pattern A53 is arranged on the other side of the mask pattern M6 in the width direction. The alignment pattern A53 is arranged on the other side of the mask pattern M6 in the flow direction. The alignment pattern A54 is arranged on one side of the mask pattern M6 in the width direction. The alignment pattern A54 is arranged on the other side of the mask pattern M6 in the flow direction. The alignment patterns A51, A52, A53, and A54 have circular shapes. The diameter of each of the alignment patterns A51, A52, A53, and A54 is smaller than the diameter of the opening 3212A of each alignment mark 32 (see FIG. 3).

[0196] When viewed from the other side in the thickness direction, the photomask PM6 is aligned with the substrate M in a state in which the center of the first mark 321 (see Figure 1) of the first alignment mark 32A coincides with the center of the alignment pattern A51, the center of the first mark 321 (see Figure 1) of the second alignment mark 32B coincides with the center of the alignment pattern A52, the center of the first mark 321 (see Figure 1) of the third alignment mark 32C coincides with the center of the alignment pattern A53, and the center of the first mark 321 (see Figure 1) of the fourth alignment mark 32D coincides with the center of the alignment pattern A54.

[0197] The center of the first mark 321 of each alignment mark 32 is calculated, for example, from the inner peripheral edge E1 (see FIG. 3) of the first mark 321. The inner peripheral edge E1 is read, for example, by image recognition through the opening 31A (see FIG. 21B) in the metal layer 31 and the first portion 3211A (see FIG. 21B) of the first insulating layer 3211.

[0198] The center of alignment pattern A51 is calculated, for example, from outer peripheral edge E61 (see FIG. 22) of alignment pattern A51. Outer peripheral edge E61 is read, for example, by image recognition. The centers of alignment patterns A52, A53, and A54 are calculated in the same way as the center of alignment pattern A51.

[0199] Next, as shown in FIGS. 21A and 21B, in the opening formation step, the etching resist PR5 is exposed through a photomask PM6 and developed.

[0200] Then, as shown in Figures 23A and 23B, the portions of the etching resist PR5 that are shielded by the mask pattern M6 and the alignment patterns A51, A52, A53, and A54 are removed, and the substrate M is exposed in the areas where the openings 5 ​​are to be formed.

[0201] Next, the substrate M exposed from the etching resist PR5 is etched to form an opening 5 as shown in FIG.

[0202] With the above steps, the assembly sheet 1 is completed.

[0203] 3. Effects (1) According to the assembly sheet 1, as shown in Figures 1 and 4, the alignment mark 32 includes a first mark 321 made of a first insulating layer 3211 and a conductive layer 3212 disposed on the first insulating layer 3211. The conductive layer 3212 of the first mark 321 has an opening 3212A.

[0204] Therefore, the contrast between the first insulating layer 3211 and the conductive layer 3212 allows the inner peripheral edge E1 of the opening 3212A to be clearly recognized.

[0205] Therefore, during the manufacturing of the assembly sheet 1, by aligning the photomasks PM2 to PM6 (see Figures 11, 13, 17, 19, and 22) for each process with the assembly sheet 1 based on the inner peripheral edge E1 of the opening 3212A, the photomask PM2 can be aligned with the assembly sheet 1 with high precision.

[0206] As a result, the positional accuracy of the photomasks PM2 to PM6 relative to the assembly sheet 1 can be improved.

[0207] Furthermore, as shown in FIG. 4, the conductor layer 3212 is covered with the second insulating layer 323, so that the conductor layer 3212 can be protected.

[0208] (2) According to the assembly sheet 1, as shown in Fig. 3, the alignment mark 32 further includes a second mark 322. The second mark 322 is disposed at an interval from the first mark 321. The second mark 322 is made of the same material as the first insulating layer 3211 of the first mark 321.

[0209] Therefore, the second mark 322 can be formed together with the first insulating layer 3211 of the first mark 321.

[0210] Therefore, as shown in FIG. 7B, the outer peripheral edge E11 of the second mark 322 can be used to align the photomask PM1 with the assembly sheet 1, and the conductor layer 3212 can be formed on the first insulating layer 3211 as shown in FIG. 9B.

[0211] (3) According to the assembly sheet 1, the metal layer 31 has an opening 31A, as shown in Fig. 4. When projected in the thickness direction, the opening 3212A of the conductor layer 3212 is located within the opening 31A of the metal layer 31.

[0212] Therefore, as shown in FIGS. 16B and 21B, the inner peripheral edge E1 of the opening 3212A of the conductor layer 3212 can be recognized through the opening 31A of the metal layer 31.

[0213] (4) According to the assembly sheet 1, as shown in Fig. 4, the first insulating layer 3211 has a first portion 3211A and a second portion 3211B. When projected in the thickness direction, the first portion 3211A is disposed within the opening 31A of the metal layer 31. The thickness of the first portion 3211A is thinner than the thickness of the second portion 3211B.

[0214] Since the thickness of the first portion 3211A disposed within the opening 31A is small, the inner peripheral edge E1 of the opening 3212A of the conductor layer 3212 can be recognized through the opening 31A and the first portion 3211A.

[0215] (5) According to the assembly sheet 1, the conductor layer 3212 is electrically connected to the metal layer 31 as shown in FIG.

[0216] Therefore, after the circuit pattern forming process and before the cover insulating layer forming process, a nickel plating layer can be formed on the surface of the conductor layer 3212 by electroless plating, while the potential of each conductor layer 3212 of the multiple alignment marks 32 is aligned via the metal layer 31.

[0217] As a result, a nickel plating layer can be formed uniformly on the conductor layer 3212 of each of the alignment marks 32.

[0218] (6) According to the assembly sheet 1, the outer periphery 3212B of the conductor layer 3212 is electrically connected to the metal layer 31, as shown in FIG.

[0219] Therefore, the conductor layer 3212 is electrically connected to the metal layer 31 at the outer periphery 3212B, which is away from the inner periphery edge E1 of the opening 3212A.

[0220] Therefore, a nickel plating layer can be formed uniformly on the conductor layer 3212 of each of the alignment marks 32, and as shown in FIG. 12B, after the conductor layer 3212 is formed, the inner peripheral edge E1 of the opening 3212A can be reliably recognized.

[0221] (7) According to the assembly sheet 1, as shown in FIG. 1, the frame 3 has a plurality of alignment marks 32.

[0222] Therefore, by using a plurality of alignment marks 32, the positional accuracy of the photomasks PM1 to PM6 relative to the assembly sheet 1 in each process can be further improved.

[0223] (8) According to the assembly sheet 1, as shown in FIG. 1, the second alignment marks 32B are smaller than the first alignment marks 32A and the third alignment marks 32C.

[0224] Therefore, by checking the position of the second alignment mark 32B, the width direction and flow direction of the assembly sheet 1 can be easily recognized.

[0225] (9) According to the assembly sheet 1, as shown in FIG. 1, the distance D1 between the first alignment mark 32A and the second alignment mark 32B in the width direction is different from the distance D2 between the second alignment mark 32B and the third alignment mark 32C in the flow direction.

[0226] Therefore, by checking the distance D1 between the first alignment mark 32A and the second alignment mark 32B in the width direction, and the distance D2 between the second alignment mark 32B and the third alignment mark 32C in the flow direction, the width direction and flow direction of the assembly sheet 1 can be easily identified.

[0227] (10) According to the method for producing the assembly sheet 1, as shown in FIGS. 6A and 6B, in the base insulating layer forming step, the first insulating layer 3211 (see FIG. 6B) is formed together with the base insulating layer 22 (see FIG. 6A).

[0228] 9A and 9B, in the circuit pattern forming step, a circuit pattern 23 (see FIG. 9A) is formed on the base insulating layer 22, and a conductor layer 3212 (see FIG. 9B) is formed on the first insulating layer 3211. This determines the positional relationship between the circuit pattern 23 and the conductor layer 3212.

[0229] Next, as shown in FIG. 10A, in the cover insulating layer forming step, the cover insulating layer 24 (see FIG. 2) is formed on the base insulating layer 22.

[0230] In the cover insulating layer forming step, as shown in FIGS. 10A and 10B, a photomask PM2 for forming the cover insulating layer 24 is aligned with the circuit pattern 23 (see FIG. 10A) using a first mark 321 (see FIG. 10B).

[0231] Therefore, the photomask PM2 for forming the cover insulating layer 24 can be aligned with the circuit pattern 23 based on the inner peripheral edge E1 of the opening 3212A of the conductor layer 3212, and the positional accuracy of the photomask PM2 with respect to the circuit pattern 23 can be improved.

[0232] (11) In the manufacturing method of the assembly sheet 1, as shown in Figures 6A and 6B, in the base insulating layer forming process, a base insulating layer 22, a first insulating layer 3211, and a second mark 322 are formed on one side of a metal substrate M.

[0233] This determines the positional relationship between the base insulating layer 22, the first insulating layer 3211, and the second mark 322.

[0234] Therefore, as shown in FIGS. 7A and 7B, in the circuit pattern forming step, the photomask PM1 for forming the circuit pattern 23 can be aligned with respect to the base insulating layer 22 using the second mark 322.

[0235] (12) The method for producing the assembly sheet 1 further includes an opening forming step of forming openings 21A in the substrate M, as shown in FIG. 14A.

[0236] In the opening forming step, as shown in FIGS. 12A and 12B, a photomask PM3 for forming openings 21A is aligned with respect to base material M using first mark 321.

[0237] Therefore, the photomask PM2 for forming the opening 21A can be aligned with respect to the substrate M based on the inner peripheral edge E1 of the opening 3212A of the conductor layer 3212, and the positional accuracy of the photomask PM2 with respect to the substrate M can be improved.

[0238] 4. Variations Next, a modified example will be described. In the modified example, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0239] (1) As shown in FIGS. 24 and 25, the conductor layer 3212 may be electrically connected to the metal layer 31 through a via 3212C that connects to the outer periphery 3212B.

[0240] 26, the third insulating layer 324 may have a slit 324A. The slit 324A is disposed on the opposite side of the second mark 322 from the first mark 321 in the radial direction of the alignment mark 32. The slit 324A exposes the metal layer 31.

[0241] (3) As shown in Fig. 27A, the wired circuit board 2 may further include a second circuit pattern 25 and a second cover insulating layer 26. In this case, as shown in Fig. 27B, the alignment mark 32 may further include a third mark 325 and a fourth insulating layer 326.

[0242] The second circuit pattern 25 is disposed on the cover insulating layer 24. The second circuit pattern 25 may be made of the same material as the circuit pattern 23. The second circuit pattern 25 may be independent from the circuit pattern 23.

[0243] The second insulating cover layer 26 is disposed on the insulating cover layer 24. The second insulating cover layer 26 covers the second circuit pattern 25. The second insulating cover layer 26 may be made of the same material as the base insulating layer 22.

[0244] The third mark 325 is disposed above the second mark 322 in the thickness direction. The third mark 325 may be made of the same material as the conductor layer 3212 of the first mark 321. The third mark 325 is disposed apart from the first mark 321. The third mark 325 is electrically connected to the metal layer 31. The outer periphery of the third mark 325 is electrically connected to the metal layer 31. The third mark 325 has a ring shape concentric with the first mark 321.

[0245] The metal layer 31 may further have an opening 31B. The opening 31B overlaps with the inner peripheral edge E4 of the third mark 325 in the thickness direction. The second mark 322 has a first portion 322A and a second portion 322B. The first portion 322A is disposed within the opening 31B when projected in the thickness direction. The second portion 322B is disposed around the first portion 322A. The thickness of the first portion 322A may be thinner than the thickness of the second portion 322B.

[0246] The fourth insulating layer 326 is disposed on the second insulating layer 323 in the thickness direction. The fourth insulating layer 326 may be made of the same material as the base insulating layer 22.

[0247] When the wired circuit board 2 has a second circuit pattern 25 and a second insulating cover layer 26, the method for producing the assembly sheet 1 further includes a second circuit pattern forming step and a second insulating cover layer forming step. The second circuit pattern forming step and the second insulating cover layer forming step are performed after the insulating cover layer forming step and before the opening forming step. The second insulating cover layer forming step is performed after the second circuit pattern forming step.

[0248] In the second circuit pattern forming step, the second circuit pattern 25 is formed on the cover insulating layer 24, and the third mark 325 is formed on the second mark 322.

[0249] More specifically, in the second circuit pattern forming step, the first mark 321 is used to align the photomask used in the second circuit pattern forming step with the circuit pattern 23 .

[0250] Next, in the same manner as in the circuit pattern forming process, the plating resist is exposed to light through a photomask and developed.

[0251] Next, the second circuit pattern 25 and the third mark 325 are formed by electrolytic plating.

[0252] In the second cover insulating layer forming step, the second cover insulating layer 26 is formed on the cover insulating layer 24, the fourth insulating layer 326 is formed on the second insulating layer 323, and the third insulating layer 324 that covers the third mark 325 is formed on the second mark 322. The second cover insulating layer 26, the third insulating layer 324, and the fourth insulating layer 326 are formed in the same manner as the cover insulating layer 24.

[0253] In detail, in the second cover insulating layer forming process, first, a photosensitive resin solution (varnish) is applied onto the second circuit pattern 25, the cover insulating layer 24, the second mark 322, the third mark 325, and the substrate M, and then dried to form a photosensitive resin coating.

[0254] Next, the first mark 321 is used to align a photomask for forming the second insulating cover layer 26 with the second circuit pattern 25 .

[0255] Next, the photosensitive resin coating is exposed to light through a photomask and developed.

[0256] According to this modification, the photomask can be aligned with the assembly sheet 1 by selecting either the first mark 321 or the third mark 325 in the opening forming step, plating step, and contour processing step.

[0257] (4) The second mark 322 and the third mark 325 do not have to have a ring shape concentric with the first mark 321. As shown in FIG. 28 , the second mark 322 and the third mark 325 may be disposed near the first mark 321, independent of the first mark 321. The centers C2 of the second mark 322 and the third mark 325 may be spaced apart from the center C1 of the first mark 321. “Near the first mark 321” refers to a distance at which the second mark 322 and the third mark 325, together with the first mark 321, fit within a single angle of view in image recognition. In this case, the opening 3212A of the first mark 321 may be covered by the second insulating layer 323 and the fourth insulating layer 326, while the inner peripheral edge E4 of the third mark may be exposed from the third insulating layer 324.

[0258] In this modification, as in the above-described modification (3), the photomask can be aligned with the assembly sheet 1 by selecting either the first mark 321 or the third mark 325 in the opening forming step, plating step, and contour processing step.

[0259] For example, in the aperture forming process and plating process, the first mark 321 can be used to align the photomask with respect to the assembly sheet 1, and in the contour processing process, the third mark 325 can be used to align the photomask with respect to the assembly sheet 1. [Explanation of symbols]

[0260] 1 Assembly sheet 2 Wiring circuit board 3 frames 22 Base insulation layer 23 Circuit Pattern 24 Cover insulation layer 31 Metal layer 31A opening (second opening) 32 Alignment Mark 32A First alignment mark 32B Second alignment mark 32C 3rd alignment mark 321 1st Mark 3211 First insulating layer 3211A Part 1 3211B 2nd part 3212 Conductor layer 3212A opening (1st opening) 3212B outer periphery 322 2nd Mark 323 Second insulating layer 324 Third insulating layer 325 3rd Mark 326 Fourth insulating layer D1 Distance D2 distance M Base material PM1 Photomask PM2 Photomask PM3 Photomask

Claims

1. a wiring circuit board; a frame having an alignment mark and supporting the printed circuit board; Equipped with The alignment mark is a first mark including a first insulating layer and a conductor layer disposed on the first insulating layer and having a first opening; a second insulating layer disposed on the first insulating layer in a thickness direction of the first insulating layer and covering the conductor layer; An assembly sheet comprising:

2. The alignment mark is a second mark arranged at a distance from the first mark and made of the same material as the first insulating layer; The assembly sheet according to claim 1 further comprising:

3. The alignment mark is a third insulating layer disposed on the second mark in the thickness direction and spaced apart from the second insulating layer; The assembly sheet of claim 2 further comprising:

4. the frame has a metal layer; The assembly sheet according to claim 1 , wherein the first insulating layer is disposed on the metal layer in the thickness direction.

5. the metal layer has a second opening; The assembly sheet according to claim 4 , wherein the first opening is disposed within the second opening when projected in the thickness direction.

6. The first insulating layer is a first portion that is disposed within the second opening when projected in the thickness direction; a second portion disposed around the first portion; and The assembly sheet according to claim 5 , wherein the thickness of the first portion is smaller than the thickness of the second portion.

7. The assembly sheet according to claim 4 , wherein the conductor layer is electrically connected to the metal layer.

8. The assembly sheet according to claim 7 , wherein an outer periphery of the conductor layer is electrically connected to the metal layer.

9. The alignment mark is a fourth insulating layer disposed on the second insulating layer in the thickness direction, The assembly sheet of claim 1 further comprising:

10. the first mark is circular, The assembly sheet according to claim 2 , wherein the second mark has a ring shape concentric with the first mark.

11. The alignment mark is a third mark disposed on the second mark in the thickness direction and made of the same material as the conductor layer; The assembly sheet according to claim 2 , further comprising:

12. the assembly sheet extends in a width direction perpendicular to the thickness direction and in a flow direction perpendicular to the thickness direction and the width direction, the frame includes a plurality of the alignment marks; The plurality of alignment marks include: a first alignment mark; a second alignment mark disposed apart from the first alignment mark in the width direction; a third alignment mark disposed apart from the second alignment mark in the flow direction; and The assembly sheet of claim 1 , comprising:

13. The assembly sheet according to claim 12 , wherein the second alignment mark is smaller than the first alignment mark and the third alignment mark.

14. The assembly sheet according to claim 12 , wherein a distance between the first alignment mark and the second alignment mark in the width direction is different from a distance between the second alignment mark and the third alignment mark in the flow direction.

15. A method for producing the assembly sheet according to any one of claims 1 to 14, comprising: The printed circuit board is a base insulating layer made of the same material as the first insulating layer; a circuit pattern disposed on the insulating base layer in the thickness direction and made of the same material as the conductor layer; a cover insulating layer that is disposed on the base insulating layer in the thickness direction, is made of the same material as the second insulating layer, and covers the circuit pattern; Equipped with The method for manufacturing the assembly sheet includes: a base insulating layer forming step of forming the first insulating layer together with the base insulating layer; a circuit pattern forming step of forming the circuit pattern on the base insulating layer and forming the conductor layer on the first insulating layer; a cover insulating layer forming step of forming the cover insulating layer on the base insulating layer; Including, The method for manufacturing an assembly sheet, wherein in the cover insulating layer forming step, a photomask for forming the cover insulating layer is aligned with the circuit pattern using the first mark.

16. In the base insulating layer forming step, the base insulating layer, the first insulating layer, and a second mark that is disposed at an interval from the first insulating layer and is made of the same material as the first insulating layer are formed on one surface of a metal substrate; The method for producing an assembly sheet according to claim 15 , wherein in the circuit pattern forming step, a photomask for forming the circuit pattern is aligned with respect to the insulating base layer using the second mark.

17. The method for manufacturing the assembly sheet includes: further comprising an opening forming step of forming an opening in the substrate; The method for producing an assembly sheet according to claim 16 , wherein in the opening forming step, a photomask for forming the openings is aligned with the base material using the first marks.

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